Medical News

'More adults should be taking statins,' says NICE

Medical News - Fri, 07/18/2014 - 13:40

"Doctors have been told to offer cholesterol-lowering statins to millions more people," BBC News reports.

New guidelines from the National Institute for Health and Care Excellence (NICE) recommend lowering the bar for statin use in adults at risk of heart disease. 

NICE suggests up to 8,000 lives could be saved every three years if everyone with a 10% risk of developing cardiovascular disease within the next 10 years is offered one of the widely used cholesterol-lowering medications.

Cardiovascular diseases are diseases affecting the heart and blood vessels, such as heart disease and stroke.

NICE says the evidence clearly shows statins are safe and effective and would be a good use of healthcare resources if given to these people.

The announcement has been met with a variable response, with the Daily Mail saying up to half of all adults could now be eligible for the drugs, and that, "GPs warn of chaos" at being "told to trawl medical records to find at-risk patients".

On the other side of the argument, Professor Baker, director of the Centre for Clinical Practice at NICE, says the new recommendations would not create an additional workload for GPs.

On the NICE website, he said: "Most patients will already be under surveillance by their GPs, so this won't add any additional workload. But you can do the QRISK2 risk assessment yourself. It can be done online or via an app, so it doesn't need to be done by the GP."

You can assess your own risk online using a risk assessment tool based on factors such as smoking history, body mass index (BMI) and family history of heart disease.

The NICE guidelines have now been published, which means they will come into effect in the NHS in England. However, NICE still recommends preventable lifestyle measures, such as losing weight or stopping smoking, are addressed first before starting statin treatment.

Ultimately, the decision to take a statin – even if it is recommended – will always remain a choice that sits with the patient.

 

What are statins?

Statins are usually the first medication of choice to reduce the levels of low-density lipoprotein (LDL, or "bad") cholesterol in the blood.

Cholesterol and other fatty substances can build up and clog the arteries in the heart and elsewhere in the body, leading to cardiovascular diseases. Reducing cholesterol levels helps reduce the risk of cardiovascular events such as heart attack or stroke.

Examples of statin drugs are simvastatin and atorvastatin, which come as tablets. The recommended treatment course is to usually take a tablet once a day for life.

 

What is NICE recommending?

NICE has published an update to its previous clinical guideline on the cardiovascular risk assessment and management of lipids (fats in the blood, which includes cholesterol and triglycerides) in people who either already have cardiovascular disease (such as those who've had a heart attack or stroke), or people who are at risk of developing cardiovascular disease.

The main new recommendations are that:

  • A systematic strategy should be used in general practice to identify people who are likely to be at high risk for developing cardiovascular disease (CVD).
  • People should be prioritised for a full risk assessment if their estimated 10-year risk of CVD is 10% or more (using the QRISK2 assessment tool).
  • Before starting lipid-lowering medications for the prevention of CVD, at least one blood sample should be taken to measure total cholesterol, high-density lipoprotein (HDL, or "good") cholesterol, non-HDL cholesterol, and triglyceride concentrations.
  • In people who have a 10% or greater risk of developing CVD within the next 10 years, the recommended statin to start treatment with is atorvastatin, given at a dose of 20mg daily.
  • In people who already have established CVD (people who have heart disease or have had a stroke), the recommended starting dose of atorvastatin is 80mg daily (unless there are side effects or other contraindications).

For people at risk of developing CVD within the next 10 years, the recommendations to start 20mg atorvastatin applies to adults of all ages, including people over the age of 85 years (in very elderly people, statins may reduce the risk of a non-fatal heart attack). This advice stands unless there are other health-related factors that make statin treatment inappropriate.

NICE does make several important provisions around decisions to start treatment for the prevention of CVD in people considered to be at risk.

These are outlined below.

Patient-doctor discussion

The decision whether to start a statin should be made after an informed discussion between the doctor and patient about the risks and benefits of treatment, taking into account factors such as:

  • possible benefits from lifestyle modifications (measures that could be tried first before starting a statin, such as exercising more, eating a healthier diet and stopping smoking)
  • patient preference
  • other medical illnesses
  • the problems of adding another tablet if the person is already taking a lot of daily medications
  • general frailty and life expectancy
Lifestyle changes

Before starting statin treatment, assessment should be made into other health and lifestyle factors that may need management, including:

  • smoking and alcohol consumption
  • blood pressure
  • BMI
  • diabetes
  • kidney or liver disease

The benefits of optimising all other modifiable lifestyle risk factors (for example, overweight/obesity or smoking) should be discussed, and people offered support for this if needed, such as exercise referral programmes.

Statin treatment may then be considered if lifestyle modifications don't work.

 

What is the rationale for lowering the threshold for the drugs?

Currently, one-third of deaths in the UK are caused by cardiovascular disease, accounting for around 180,000 deaths each year.

Cardiovascular disease is well known to have a significant burden of disability. It is believed £8 billion of healthcare resources are tied up in the disease.

Professor Mark Baker, director of the Centre for Clinical Practice at NICE, says: "Doctors have been giving statins to 'well people' since NICE first produced guidance on this in 2006. We are now recommending the threshold is reduced further.

"The overwhelming body of evidence supports their use, even in people at low risk of CVD. The effectiveness of these medicines is now well proven and their cost has fallen. The weight of evidence clearly shows statins are safe and cost effective for use in people with a 10% risk of CVD over 10 years."

Dr Anthony Wierzbicki, from Guy's and St Thomas' Hospitals, London, and chair of the Guideline Development Group, also commented on the new guidance: "We've been able to simplify the guideline so it's now much easier for patients to be assessed and for GPs and nurses to make sense of the results. There is greater clarity, a simpler framework, and a systematic way of identifying people who could benefit from treatment.

"We've got the best evidence base, huge numbers, and the biggest set of clinical trials ever done. Other areas of medicine would give their teeth for this evidence, it's that good. Statins work, they are very cheap, and are becoming considerably cheaper as they come off-patent, which, in a cost-limited health service, is a big consideration.

"That enables us to actually say that we should treat people with heart disease a lot more intensively because we know that will prevent further events. In people with diabetes or kidney disease, giving a statin will reduce heart attacks and strokes. For people at risk of heart disease, if lifestyle measures fail, we have a second option of giving them a statin if they want and require it."

 

Are there any risks or side effects with statins?

Statins are fairly safe drugs, though there are a range of possible side effects and groups of people who should use them with caution. This includes people with an underactive thyroid, kidney disease and liver disease. Women should also not take statins while pregnant or breastfeeding.

Possible side effects include headaches and dizziness, sleep disturbances, fatigue, tummy disturbances, altered sensation, and sensitivity reactions such as rash or itching.

Very rarely, statins have been associated with the risk of having a toxic effect on the muscles, causing muscle pain and weakness, and even a serious condition called rhabdomyolysis, where the muscle fibres start to break down.

However, the risks and benefits would be discussed and taken into account for any individual before a statin is prescribed, including their personal and family medical history.

 

How has the announcement been received by the media?

As the BBC News headline indicates, NICE's decision has been met with controversy. 

Professor Mark Baker, the director of the Centre for Clinical Practice at NICE is quoted as saying: "Prevention is better than cure. One of the mainstays of modern medicine is to use treatments to prevent bad things happening in the future. It's why we use vaccines and immunisation to prevent infectious disease, it's why we use drugs to lower blood pressure to prevent heart attacks, strokes, and kidney disease, and it's why we're using statins now."

Meanwhile, in opposing camps there is debate about "medicalising" a nation and encouraging people to just pop a pill rather than following a healthy lifestyle.

The British Medical Association's General Practitioner Committee is quoted as saying: "There is insufficient evidence of significant overall benefit to low-risk individuals to allow GPs to have confidence in the recommendation. The measure would distort health spending priorities and disadvantage other patients."

However, as quoted in the Daily Mail, Professor Baker responded: "It is ludicrous to suggest that we are overmedicalising the population when the whole point of using modern, safe and effective drugs in an economic way is to prevent bad things happening in the future."

Dr Chaand Nagpaul, chair of the British Medical Association's GP committee, feels NICE has not taken into account the additional pressures they'll be placing on GPs. "In making their decision, NICE has failed to take the current pressures on general practice into account, and the further impact this will have on already overstretched GPs and those patients requiring treatment for other illnesses."

Despite the extensive debate and opposition, as BBC News also highlights, the 10% threshold for statin treatment is comparable to that already used in other European countries.

As the president of the Academy of Medical Sciences, Professor Sir John Tooke, points out on the BBC News website: "Whether or not someone takes drugs to diminish their risk is a matter of personal choice, but it must be informed by accurate information on the balance of risk and benefit in their particular case. The weight of evidence suggests statins are effective, affordable and have an acceptable risk-benefit profile."

 

Conclusion

Despite somewhat hysterical media coverage to the contrary ("millions more to be given statins," according to the Daily Express), nobody will be forced to take statins.

If your GP does recommend statins, you should ask them to explain the benefits and risks for you personally of starting statin treatment. You may want to find out more about statins before making up your mind – the NHS Choices Health A-Z information on statins is a good place to start.

If you do experience troublesome side effects while taking statins, contact your GP or the doctor in charge of your care. It could be the case that adjusting your dosage or switching to a different type of statin could help relieve any side effects.

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter. Join the Healthy Evidence forum.

Links To The Headlines

Statins: Millions more to get drugs in controversial plans. BBC News, July 18 2014

Prescribing statins more widely 'could avert tragedy', new medical guidelines suggest. The Independent, July 18 2014

NHS medicines watchdog lowers bar for statins prescriptions. The Guardian, July 18 2014

Forty per cent of adults advised to take statins under new NHS guidance. The Daily Telegraph, July 18 2014

GPs warn of chaos over bid to offer statins to 17m to prevent heart disease: Doctors being told to trawl medical records to find at-risk patients. Daily Mail, July 18 2014

Statins to be offered to '40% of adult population'. ITV News, July 18 2014

Give statins to 17m says NHS watchdog. Daily Express, July 18 2014

Links To Science

National Institute for Health and Care Excellence. Lipid modification: cardiovascular risk assessment and the modification of blood lipids for the primary and secondary prevention of cardiovascular disease. July 2014

Categories: Medical News

Steroid asthma inhalers restrict children’s growth

Medical News - Thu, 07/17/2014 - 14:50

“Children who use inhalable steroids for asthma grow slower than their peers in the first year of taking the medication,” The Guardian reports. While this is an accurate report of the science, the effect found by researchers was small. On average, a reduction of around half a centimetre per year was seen, compared to children taking a placebo or other asthma medication.

The researchers were studying the effects of inhaled corticosteroids. These are known as “preventers” – the brown inhalers that deliver a dose of steroids to the airways reducing inflammation, to prevent symptoms.

After pooling the results of 25 trials, they found a small but significant link between the use of preventer inhalers and restricted childhood growth, which was estimated to be an average reduction of 0.48cm (or 0.19in).

The authors recommend that these drugs should be prescribed at the “lowest effective dose” and that the growth rate of children treated with inhaled corticosteroids should be monitored, as they will affect each child differently.

However, as the authors point out, the small effect on growth is a minor risk compared to the proven benefits of these drugs in controlling asthma, and ensuring children’s lungs grow to their full capacity.

Untreated childhood asthma is much more likely to have a harmful effect on a child’s development than a small reduction in growth.

It is therefore important that parents ensure their children use their inhalers as advised by their doctor.

 

Where did the story come from?

The study was carried out by researchers from the Federal University of Rio Grande, Brazil, and the University of Montreal, in Canada. There was no external funding.

The study was published by the Cochrane Collaboration – an independent research body looking at the effects of healthcare treatments.

As with all Cochrane Collaboration publications, the research was peer-reviewed. It is available on an open-access basis, so is free to read online.

Not surprisingly, it was widely covered by the media, with most news sources responsibly including warnings from independent researchers and doctors that uncontrolled asthma can be dangerous.

The Independent rightly report that the effect of inhalers on growth was “a small price to pay” to protect against potentially lethal asthma attacks.

 

What kind of research was this?

This was a systematic review and meta-analysis of the evidence on whether drugs called “inhaled corticosteroids” (steroids) can affect the growth of children with persistent asthma.

Children with persistent asthma often require regular use of this medication to prevent symptoms, such as wheezing, from reoccurring.

The researchers also investigated whether factors such as the type of medication, dose, the length of time taken and the type of inhalation device used had any role in modifying the potential effect on growth.

Systematic reviews of randomised controlled trials (RCTs) are the best way of assessing the benefits and risks of healthcare interventions. A meta-analysis is a statistical technique that combines the results of several studies.

Inhaled steroids are recommended as a first line treatment for children with persistent, mild to moderate asthma. These drugs are the most effective method of treating asthma and are generally considered safe. However, parents and doctors remain concerned about the potential negative effect on growth, which has been suggested by previous research. Their aim was to evaluate the adverse effects on growth in children of all the currently available inhaled steroids.

 

What did the research involve?

The researchers searched for trials that addressed this question on a Cochrane specialist register of trials, which is derived from systematic searches of various electronic databases. They also hand-searched respiratory journals and meeting abstracts. All databases were searched from their inception to January 2014.

They looked for RCTs involving children up to 18 years of age, with persistent asthma, who had used ICS daily for at least three months, and who had been compared with children using a placebo or non-steroid drug.

They then assessed children’s rate of linear growth by measuring height at a number of points in the study.

Differences between growth rate and predicted normal growth rates for children of the same age, sex and ethnicity, and changes from baseline in height over time were also considered.

The authors of the Cochrane research assessed the abstracts of all studies identified as potentially relevant, and where they met the study criteria, extracted the relevant data. They also independently assessed the quality of the trials and the risk of bias. The quality of RCTs may vary, depending on how well they are designed, conducted and reported.

They used validated statistical methods to analyse the results.

 

What were the basic results?

The review included 25 trials, involving 8,471 children with mild to moderate persistent asthma.

The trials tested six medications (beclomethasone dipropionate, budesonide, ciclesonide, flunisolide, fluticasone propionate and mometasone fumarate), given at low or medium daily doses during a period of three months to four to six years.

They found that:

  • compared with placebo or non-steroidal drugs, inhaled steroids produced a statistically significant reduction in a person’s growth rate (mean difference -0.48cm/y, 95% Confidence Interval [CI] 0.65 to 0.30, moderate quality evidence)
  • this represented an overall decrease from the expected baseline in height (mean difference 0.61cm/y, 95% CI 0.83 to 0.38, moderate quality evidence) during a one-year treatment period (that is, on average, children were 0.61cm shorter than would have been expected)
  • the scale of growth reduction in children treated with inhaled steroids varied according to the type of drugs used, with the smallest reduction found for ciclesonide, but this was based on just one study of 202 children
  • results for further years varied between trials, but overall, growth reduction was less pronounced in subsequent years of treatment
  • one trial that followed children into adulthood showed that prepubertal children treated with the drug budesonide for an average of 4.3 years had an average reduction of 1.20cm (95% CI 1.90 to 0.50) in adult height, compared to those treated with a placebo

second Cochrane review of 22 trials found that the effects on growth were minimised when lower doses of inhaled steroids were used.

 

How did the researchers interpret the results?

The researchers say the evidence suggests that children treated daily with inhaled steroids may grow about half a centimetre less during their first year of treatment, with the effect on growth less pronounced in subsequent years.

Further research is now needed, they say, comparing different inhaled doses of corticosteroids, especially in children with more severe asthma, who require higher doses.

They conclude that while the benefits of inhaled steroids outweigh the potential risk of a relatively small suppression in growth rates, these drugs should be prescribed at the “lowest effective dose”, and the growth rate of children treated with inhaled steroids drugs should be monitored, since individual susceptibility may vary.

 

Conclusion

This systematic review has found that inhaled corticosteroid drugs suppress growth in children with persistent asthma who take them regularly, during the first year of treatment.

This was high quality, well-conducted research, and its conclusions are likely to be reliable. 

While the results are likely to worry parents, uncontrolled asthma can restrict a child’s activities and lower their quality of life. In severe cases, it can lead to life-threatening asthma attacks.

Even low-grade, persistent symptoms can lead to fatigue, underperformance or absence from school as well as psychological problems, including stress, anxiety and depression.

It's important that children continue to take their asthma medication as prescribed. Parents should discuss any concerns about their child’s prescription with their doctor.

Analysis by Bazian. Edited by NHS ChoicesFollow Behind the Headlines on TwitterJoin the Healthy Evidence forum.

Links To The Headlines

Asthma inhaler use in children slows growth, research finds. The Guardian, July 17 2014

Asthma inhalers make children half a centimetre shorter. The Daily Telegraph, July 17 2014

Asthma inhalers 'can stunt growth of kids'. Daily Mirror, July 17 2014

Asthma inhalers 'stunt growth': Most widely-used device found to reduce height in first year of use. Mail Online, July 17 2014

Asthma inhalers can stunt growth in children, new research finds. The Independent, July 17 2014

Links To Science

Zhang L, Prietsch SOM, Ducharme FM. Inhaled corticosteroids in children with persistent asthma: effects on growth. Cochrane Database of Systematic Reviews. Published online July 17 2014

Categories: Medical News

Protein may help control diabetes symptoms

Medical News - Thu, 07/17/2014 - 14:25

"Diabetes could be cured 'in single jab'," is the misleading headline in the Daily Express. The news comes from an exciting new mouse study which found promising results for a treatment for type 2 diabetes.

However, the study did not show that it would cure diabetes, and certainly not after a single injection.

Researchers performed experiments in mice using a protein called fibroblast growth factor 1 (FGF1). FGF1 works in a similar way to an existing class of diabetes drugs called thiazolidinediones by making the body's cells more sensitive to insulin-reducing blood sugar levels.

Unfortunately, using thiazolidinediones in humans causes side effects such as weight gain, which can be problematic in patients who are often already overweight.

Researchers found repeated injections of FGF1 every other day for 35 days in mice improved their insulin sensitivity and lowered blood sugar levels without any noticeable side effects. However it is unlikely there would be no side effects in humans.

It is too early to say this would be a "cure" for diabetes, and further research is required before human trials are conducted. This is a promising new avenue of study, however.

 

Where did the story come from?

The study was carried out by researchers from the Salk Institute for Biological Studies, New York University School of Medicine, and the University of California, San Diego, in the US, the University of Groningen in the Netherlands, and the Westmead Millennium Institute and the University of Sydney in Australia.

It was funded by the US National Institutes of Health, the Glenn Foundation for Medical Research, the Australian National Health and Medical Research Council, the European Research Council, and several US and Dutch foundations and research organisations.

The study was published in the peer-reviewed journal, Nature.

The Daily Express' headline claiming this study could lead to a diabetes cure was inappropriate and not supported by the study's findings.

The Daily Mail and Daily Mirror's coverage was more restrained, and the Mirror print edition included a useful diagram explaining how the treatment could work in humans.

There are, however, some inaccurate reports the treatment reverses insulin resistance. This was not shown in the study – the treatment improved insulin sensitivity by about 50%. This is not the same thing as reversing insulin resistance.

 

What kind of research was this?

This was a series of laboratory and animal experiments that aimed to see if a protein normally present in mammals called fibroblast growth factor 1 (FGF1) could reduce high blood glucose (sugar) levels.

The FGF1 protein is known to have a role in new blood vessel formation (angiogenesis) and cell division, and is also thought to be involved in organ development. It has been used in human studies as a treatment for peripheral vascular disease.

Scientists have suspected FGF1 is also involved in the regulation of blood glucose levels, as genetically modified mice that do not have this protein develop insulin resistance when they are given a high-fat diet.

The hormone insulin is required for cells to take in glucose for energy. When insulin resistance occurs, there is a reduction in the ability of cells to take in glucose. This can lead to type 2 diabetes. The researchers wanted to see if the insulin resistance could be reversed by giving mice FGF1.

 

What did the research involve?

The researchers conducted a variety of experiments to investigate the effects of FGF1 on blood glucose levels in mice.

They gave a single injection of recombinant FGF1 (rFGF1) from rodents into diabetic mice and normal mice, and then measured their blood glucose levels.

The researchers also injected recombinant human FGF1 to see if it had the same effect. They injected other types of fibroblast growth factors, such as FGF2, FGF9 and FGF10, into diabetic mice and then measured blood glucose levels.

The researchers performed repeated injections of rFGF1, one every other day for 35 days, assessed the effects on blood glucose and insulin sensitivity, and monitored the mice for side effects.

They investigated whether the effects were related to rFGF1 increasing the levels of insulin being released, or whether it was using a different mechanism. This also involved injecting mice that could not produce insulin (similar to type 1 diabetes).

Another aspect of the study investigated whether the researchers could modify the rFGF1 to stop it causing unwanted cell division, but still be able to reduce blood glucose levels. They did this by removing some of the amino acids in the protein and testing it in the laboratory and then in mice.

 

What were the basic results?

A single injection of rFGF1 into diabetic mice reduced their high blood sugar levels to normal levels with a maximum effect between 18 and 24 hours. The effect lasted for more than 48 hours. Blood sugar levels did not go dangerously low (hypoglycaemia).

Similar results were found if the injection was into the bloodstream or the peritoneal cavity (the space around abdominal organs).

When normal mice were injected, there was no change in blood sugar level. Other types of FGF proteins did not reduce blood sugar levels. Human rFGF1 injections were also found to work in the mice.

Repeated injections of rFGF1 improved the ability of skeletal muscle to take in glucose, indicating it improved the cells' sensitivity to insulin.

The fasting blood glucose level of the mice was 50% lower than mice given a control injection with saline. Insulin tolerance test (ITT) results also improved, showing the mice had become more sensitive to insulin again.

The mice did not gain weight, their livers did not become fatty, and there was no bone loss with the treatment, all side effects of current therapies that aim to improve insulin sensitivity, such as thiazolidinediones.

The mice appeared to have normal activity levels and breathing rates. FGF1 did not make the pancreas release more insulin in laboratory or mouse experiments.

In mice without the ability to produce insulin (similar to type 1 diabetes), rFGF1 did not reduce their blood sugar levels. However, it did improve the level of blood sugar reduction when insulin was then injected.

These results suggest that rFGF1 may cause cells to become more sensitive to insulin.

Removing some of the amino acids from rFGF1 stopped it inducing cell division in laboratory experiments, but it was still able to reduce blood sugar levels in the mice.

 

How did the researchers interpret the results?

The researchers concluded they have uncovered an unexpected action of human FGF1, which they say has "therapeutic potential for the treatment of insulin resistance and type 2 diabetes".

 

Conclusion

This exciting study has shown potential for rFGF1 to become a treatment for both type 1 and type 2 diabetes. The mouse studies have shown that for type 2 diabetes, rFGF1 reduces blood glucose levels in a sustained manner, and its prolonged use improves insulin sensitivity.

There is also potential for rFGF1 to improve blood glucose control for type 1 diabetes, though it would not replace the requirement for insulin injections.

The researchers have also shown they can modify rFGF1 so it doesn't cause unwanted cell division in laboratory experiments.

But further investigations are needed to see whether this version only has an effect on blood glucose levels or whether it retains its other known functions, such as new blood vessel formation, which may potentially cause side effects.

Encouragingly, the researchers did not find any side effects with the treatment, but it was only given over a maximum of 35 days.

Further research will be required before human trials are conducted, but this is a promising new avenue of study.

Even if any drug that stems from this research did prove to be effective and safe in humans, it is unlikely it would lead to a permanent cure for diabetes. It is more likely it would become a maintenance treatment a person would need to take long term on a regular basis.

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter. Join the Healthy Evidence forum.

Links To The Headlines

Diabetes could be cured 'in single jab'. Daily Express, July 17 2014

Protein discovery that could reverse the damage of diabetes: Breakthrough could lead to cheap drug that would halt disease. Daily Mail, July 17 2014

Diabetes breakthrough drug can work for two days from a single jab. Daily Mirror, July 16 2014

Links To Science

Suh JM, Jonker JW, Ahmadian M, et al. Endocrinization of FGF1 produces a neomorphic and potent insulin sensitizer. Nature. Published online July 16 2014

Categories: Medical News

Owning a dog may make older adults fitter

Medical News - Wed, 07/16/2014 - 15:00

“Want to appear 10 years younger? Just buy a dog,” is the dubious claim on the Mail Online.

A study has found a link between dog ownership and increased physical activity in older adults, but how this is linked to looking younger is unclear.

Contrary to the headline, the study did not measure or mention physical appearance.

The study actually measured physical activity levels of 547 older adults in Tayside, Scotland. After taking factors such as weather, environment, medical illnesses and socioeconomic status into account, dog owners were 12% more physically active than people who did not own a dog.

The authors say that this difference was equivalent to the activity level of someone 10 years younger.

Although the study also revealed that dog owners had better general health and physical functioning, it cannot prove that this was due to owning a dog.

It should also be noted that these results are based on just 50 dog owners and so may not be generalisable to the whole population.

However, it is clear that exercise and walking are beneficial to physical and mental health and should be encouraged across all age groups.

So it is recommended that you go for regular “walkies”, whether or not you are accompanied by a canine companion.

 

Where did the story come from?

The study was carried out by researchers from the University of St Andrews, the University of Dundee and the University of Newcastle and was funded by a Chief Scientist Office Scottish government grant.

The study was published in the peer-reviewed medical journal Preventive Medicine.

Like many Mail Online health stories, while the story itself was broadly accurate (though it didn’t make clear that the study cannot prove causality) the headline bore little resemblance to reality.

Regular exercise can improve flexibility and bone strength and make you feel younger, but this is not the same as “appear[ing] 10 years younger”.

It could be the case that the headline was shoehorned in due to the Mail Online’s obsession with physical appearance. The most notorious example being the so-called “Sidebar of Shame” – the list of photo captions on the right of the website, which are mainly about how celebrities look.

 

What kind of research was this?

This was a cross-sectional study of older adults in Scotland. It aimed to see if there was a link between owning a dog and increased activity levels. As it is a cross-sectional study, it is only able to look at one point in time therefore it cannot prove cause and effect, it can only show associations.

 

What did the research involve?

The researchers used data from a study called the Physical Activity Cohort Scotland (PACS). Adults over the age of 65 were recruited from 17 GP practices across Tayside in Scotland. They were randomly selected from these practices to have a sample that included people from rural, urban, deprived and less deprived areas.

People were excluded from the study if they were in residential care, wheelchair or bedbound, had cognitive impairment, or were in another study.

Of the 3,343 people invited to take part, 584 people agreed and this study used the details from 547 of them.

The study was conducted between October 2009 and February 2011. Each participant was asked to wear an accelerometer (a device, usually electrical, that measures physical movement) for seven days to record their level of physical activity. They were requested not to change their usual pattern of activity during that week. They also filled out the following questionnaires:

  • Older People and Active Living (OPAL) questionnaire which included information on their housing, marital status, education level, pet ownership and chronic medical illnesses
  • Hospital Anxiety and Depression Score (HADS)
  • SF-36, which measures general health status
  • Social Capital Questionnaire, which captures relationship networks – such as how many friends and family an individual is in regular contact with
  • London Health and Fitness Questionnaire, which covers attitudes towards physical activity and past experiences of physical activity
  • an item from the Extended Theory of Planned Behaviour Questionnaire, which asked them to rate how strongly they agreed or disagreed with the sentence “I intend to do 30 min of moderate-intensity physical activity on five or more days in the forthcoming week”

The researchers also collected data on weather conditions during the accelerometer use from the UK Meteorological Office as they say that “dog walking behaviour is fairly robust to inclement weather especially in a temperate climate, whereas other types of walking are not”. That is dog walkers are more likely to brave the rain than people who walk for pleasure or exercise.

They performed statistical analyses to look for associations between level of physical activity and pet ownership. They then accounted for various potential confounding factors such as their environment, medical illnesses and socioeconomic status.

 

What were the basic results?

The average age of the participants was 79. Fifty people (9%) owned a dog, and their average age was 77.

When no other factors were taken into account, according to the accelerometer readings, dog owners were 27% more physically active than non-dog owners. When the analysis took into account all of the environmental and medical factors, dog owners still had 12% higher levels of physical activity.

Dog owners were significantly more likely to:

  • be married
  • live in rural areas
  • have been physically active between leaving school and being 25 years old
  • have the intention to be physically active
  • have perceived behavioural control
  • have better general health and physical functioning

Dog owners were also less likely to have symptoms of depression.

How did the researchers interpret the results?

The researchers say that this study shows that “on average, older dog owners were 12% more active than their counterparts who did not own a dog. This difference is equivalent to the levels of PA [physical activity] between people who differ by 10 years in age”.

They suggest that “interventions to increase activity amongst older people might usefully attempt to replicate elements of the dog ownership experience”.

In an interview with the Mail, the lead researcher Dr Zhiqiang Feng, mentions the possibility of developing an app that replicates the experience of owning a dog by prompting its “owner” to take it for “walkies” at regular intervals.

 

Conclusion

Despite media claims, this study has not shown that dog owners have bodies that appear 10 years younger than people who do not own dogs.

However, it has shown a difference in physical activity between dog owners and non-dog owners of around 12%. This was reported by the authors as being the same as the difference between people who are 10 years apart in age.

It should be noted that this figure comes from the same sample of people, reported in a previous paper. It found that the accelerometry counts were highest in affluent adults aged 65 to 80, followed by deprived adults aged 65 to 80, with lowest levels in deprived adults over 80 years old.

Strengths of the study include the attempt to recruit a diverse section of the population. However there is potential bias in the population sample as only 19% of people invited to take part in the study agreed.

Therefore it may be that this sample is not representative of the whole population, but is perhaps a group of people who are more motivated or interested in physical activity. The results are also based on a sample of just 50 dog owners. It also excluded people who were in residential care, wheelchair or bedbound or had cognitive impairment, some of whom are likely to be dog owners.

The researchers attempted to account for differences in physical activity levels according to the weather at the time the accelerometer readings were taken.

However, it is not clear whether each participant wore the accelerometer at the same time of the year, which could have an effect on activity levels and ability to be outside.

Overall this study shows that being a dog owner is associated with higher levels of physical activity and general health, presumably because of the requirement to take them for walks each day, but this study cannot prove that this is the cause of the results seen.

However, it is clear that exercise and walking are beneficial to physical and mental health and should be encouraged across all age groups.

Walking just 30 minutes, five times a week, can bring considerable health benefits over time.

And, as a story we covered earlier this week suggested, it may even help lower your dementia risk.

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter. Join the Healthy Evidence forum.

Links To The Headlines

Want to appear 10 years younger? Just buy a dog. Mail Online, July 15 2014

Links To Science

Feng Z, Dibben C, Witham MD, et al. Dog ownership and physical activity in later life: A cross-sectional observational study. Preventive Medicine. Published online June 12 2014

Categories: Medical News

Prediabetes label unhelpful, experts argue

Medical News - Wed, 07/16/2014 - 14:17

“Pre-diabetes label ‘worthless’, researchers claim,” reports the BBC.

The headline is based on an opinion piece published in the British Medical Journal (BMJ) by John Yudkin and Victor Montori, both of whom are professors of medicine.

They argue that diagnosing people with “prediabetes” puts people at risk of unnecessary medicalisation and creates an unsustainable burden on healthcare systems.

The piece is part of an ongoing BMJ series called “Too much medicine”, which is examining what is known as over-medicalising – treating “problems” that don’t actually require treatment.

They argue that money would be better spent changing food, education, health and economic policies.

This is an opinion piece. Although the authors support their opinions with studies, other evidence available could contradict their views.

 

What is meant by ‘prediabetes’?

Prediabetes is used to describe people at risk of diabetes because they have impaired glucose metabolism, but who do not meet the criteria for diabetes and often have no noticeable symptoms.

It is a term that was introduced by the American Diabetes Association (ADA), but has not been accepted by other health organisations, such as the World Health Organization (WHO).

It may be defined as:

  • impaired glucose tolerance
  • above normal glucose blood concentration after fasting
  • above normal glycated haemoglobin (a marker of average blood glucose concentration)

Supporters of the term’s usage argue that it allows doctors to identify high-risk patients, so they can be treated in order to prevent diabetes from occurring.

 

What objections do the authors have about the use of the term?

The authors point out that there has been little support for the ADA’s prediabetes label from other expert groups, including WHO, the International Diabetes Federation and the UK’s National Institute for Health and Care Excellence (NICE).

The authors say this is because the ADA has lowered the thresholds for impaired fasting glucose and glycated haemoglobin. Because it encompasses all three aspects of impaired glucose metabolism (impaired glucose tolerance, above normal fasting blood glucose, above normal glycated haemoglobin), the lowered thresholds have created a large, poorly characterised and heterogeneous (mixed) category of glucose intolerance.

In other words, the diagnostic criteria are now so broad (in the opinion of the authors) that it is, essentially, useless.

The authors say that using the ADA’s definition of prediabetes would result in two to three times as many people being diagnosed with impaired glucose metabolism. This would lead to 50% of Chinese adults being diagnosed with prediabetes – over half a billion people.

The authors also question the value of diagnosing people with prediabetes.

They point out that the drugs used to treat people with prediabetes in order to stop them developing diabetes are often the same as the drugs they would take if they actually developed diabetes.

The side effects of these drugs must be measured against the fact that many people with prediabetes, who remain untreated, will not go on to develop the condition.

They also discuss the merits of lifestyle interventions, such as regular exercise and improved diet.

They point out that these types of interventions are of use for all adults, so they question the wisdom of only promoting these interventions to specific groups. A better use of campaigning would be to target all adults, they say.

 

What dangers or risks do they claim could occur by using the term?

The authors suggest that a label of prediabetes, while not causing any physical symptoms, could still cause:

  • problems with self-image
  • anxiety about future complications
  • challenges with insurance and employment
  • a need for medical care and treatment
  • increased healthcare costs
  • medication side effects, if prediabetes is treated with drugs

In their opinion, the diagnosis would cause more problems than it solves.

 

What do the researchers suggest instead?

The researchers say that the risk factors for developing a whole host of chronic diseases overlap, and that money would be better spent changing food, education, health and economic policies.

 

What should I do if I have been told I have prediabetes or that I am at high risk of developing diabetes?

If you have been told you have prediabetes, or that you have a high risk of developing diabetes, you can reduce your risk of developing the illness by:

Read more advice about lowering your diabetes risk.

Analysis by Bazian. Edited by NHS ChoicesFollow Behind the Headlines on TwitterJoin the Healthy Evidence forum.

Links To The Headlines

Pre-diabetes label 'worthless', researchers claim. BBC News, July 16 2014

Millions unnecessarily labelled pre-diabetic, health experts say. The Guardian, July 15 2014

Links To Science

Yudkin JS, Montori VM. The epidemic of pre-diabetes: the medicine and the politics. BMJ. Published online July 15 2014

Categories: Medical News

Study explores effect of plain cigarette packs

Medical News - Tue, 07/15/2014 - 15:00

"Long-term smokers find the taste of plain-packaged cigarettes worse than that of branded cigarettes," The Guardian reports.

The news comes from Australian research into the impact of plain packaging and health risk warnings on packets of cigarettes and anti-smoking TV adverts.

The researchers found highly emotive warnings were more likely to capture the attention of the study's participants. However, these warning messages did not actually prompt the smokers to try to quit.

Interestingly, some smokers reported they felt the quality and taste of cigarettes had worsened or different brands now all tasted the same after plain packs were introduced.

While this may well be a minority view, it does suggest the effects of branding could have a psychological influence on some smokers, changing how they perceive the quality of the product.

This may explain why tobacco companies have been lobbying against similar laws being introduced in the UK.

Further research is needed to determine the best ways of engaging with vulnerable smokers.

 

Where did the story come from?

The study was carried out by researchers from the University of Newcastle and the Hunter Medical Research Institute in Newcastle, Australia.

It was funded by an Australian Postgraduate Award PhD Scholarship, the Cancer Institute New South Wales, and Newcastle Cancer Control Collaboration.

The study was published in the peer-reviewed journal Health Education Research.

The Guardian's headline, "Long-term smokers find plain-packaged cigarettes taste worse", gives a false impression of the findings of this study. The researchers did not compare the taste of branded and plain-packaged cigarettes.

Following the implementation of plain packaging, perceptions of the quality and taste of cigarettes did change for some participants.

However, it is unclear from the research article whether this was a majority view, and the research itself was not designed to address the question of whether plain-packaged cigarettes taste different.

 

Links To The Headlines

Long-term smokers find plain-packaged cigarettes taste worse. The Guardian, July 15 2014

Links To Science

Guillaumier A, Bonevski B, Paul C. Tobacco health warning messages on plain cigarette packs and in television campaigns: a qualitative study with Australian socioeconomically disadvantaged smokers. Health Education Research. Published online June 25 2014

Categories: Medical News

Spoons lead to inaccurate medicine doses for kids

Medical News - Tue, 07/15/2014 - 14:15

“Using a spoon to measure medicine for children can lead to potentially dangerous dosing mistakes,” the Daily Mail reports.

Parents have long been instructed to provide liquid medication to their children in dosages measured using teaspoons and tablespoons. The rationale behind the advice is that this provides a quick and easy way for parents to calculate the correct dose.

However, a new study suggests that many parents misinterpret this advice, leading to either under or overdosing, which could be potentially harmful for a child.

The study involved 287 parents of children aged under nine years who were prescribed a daily oral liquid medication for two weeks or less.

After the end of the medication course, parents were asked about the dose of medication they were supposed to be giving their child and how they measured it. 

The researchers found that dosing errors of medications are common, with nearly a third of parents making an error in knowledge of the prescribed dose. Around one in six parents used a kitchen spoon rather than a teaspoon or tablespoon to measure out liquid medicines.

The researchers found that errors were less common when the unit of measurement used to describe the dose was millilitre rather than teaspoon/tablespoon.

The researchers conclude that this suggests moving to a millilitre-only standard – which can be delivered using a dropper, oral syringe or dosing spoon – as this could reduce confusion and decrease medication errors.

Where did the story come from?

The study was carried out by researchers from New York University School of Medicine, Bellevue Hospital Center and Woodhull Medical Center in New York, and Pennsylvania State University College of Medicine.

It was funded by the US National Institutes of Health, the National Institute of Child Health and Human Development and Nation Center for Research Resources.

The study was published in the peer-reviewed journal Pediatrics.

The research was well reported by the Daily Mail.

 

What kind of research was this?

This was a cross-sectional study, with information gathered at one point in time.

The researchers were concerned about the lack of standard units of measurement for oral liquid medications for children.

Instead, parents may be told to measure doses in:

  • millilitres (ml)
  • teaspoons
  • tablespoons
  • milligrams
  • dropperfuls
  • cubic centimetres

Understandably, this can lead to confusion.

In addition, the researchers were also concerned about expressing doses in teaspoons and tablespoons, because if parents mix-up these units it can lead to children being given either a third or three times the intended dose. One teaspoon is equivalent to 5ml and one tablespoon is equivalent to 15ml. 

Furthermore, expressing doses in this way may lead to kitchen spoons being used to measure doses, and these vary widely in size and shape.

 

What did the research involve?

The researchers studied 287 parents of children aged under nine years who were prescribed a daily oral liquid medication for two weeks or less at one of two hospital paediatric emergency departments in New York.

Between four days and eight weeks after the end of the prescribed medication course, parents were asked to report the dose they gave their child, and the researchers performed a dosing assessment.

In the dosing assessment, researchers watched parents after they were asked to dose the medication as they would at home.

They were given a standard medication bottle and asked to use the dosing instrument they used or to select a comparable one from a range provided. The range consisted of a kitchen teaspoon, kitchen tablespoon, dosing spoon, measuring spoon, dosing cup, 5ml dropper, acetaminophen (the US term for paracetamol) infant dropper, ibuprofen-specific dropper and 1-, 3-, 5-, 10- and 12-ml oral syringes.

The researchers compared the results with the prescribed dose to see if there was an error:

  • in knowledge of the child’s prescribed dose
  • in measurement compared to the parent’s intended dose (dose the parent reported giving)
  • in measurement compared to the child’s prescribed dose

To be classified as an error the difference had to be more than 20%.

The researchers looked at if the likelihood of an error depended on:

  • whether parents used a nonstandard dosing instrument (kitchen teaspoon or tablespoon)
  • the unit of measurement used

The researchers adjusted their analyses for child and parent age and gender, parent-preferred language, ethnicity, level of education, socioeconomic status, parent health literacy and child’s chronic disease status.

 

What were the basic results?

The researchers found that:

  • nearly a third (31.7%) of parents made an error in knowledge of the prescribed dose
  • about 40% (39.4%) made an error in measurement of dose compared to the parent’s intended dose
  • about 40% (41.1%) made an error in measurement of dose compared to the child’s prescribed dose
  • around one in six parents (16.7%) used a kitchen spoon rather than a standard measurement instrument (oral syringe, dropper, dosing cup or spoon, or measuring spoon)

The researchers found that units of measurement in the child’s prescription, on the medication bottle, and that the parent reported often did not correspond, with the bottle label not containing the same units as the prescription more than a third of the time (36.7%), and parents not using the unit listed in the prescription or label. The researchers thought that parents were likely to have been exposed to different units as part of verbal instructions from the clinician prescribing the medication.

Units of measurement on the prescription or the bottle were not associated with errors in knowledge or measurement; however, the unit reported by the parent was associated with both types of error:

  • Compared with parents who used ml only, parents who used teaspoons or tablespoons were more likely to make errors in measurement compared to their intended dose (adjusted odds ratio [AOR] 2.3; 95% confidence interval [CI], 1.2 to 4.4) and to the prescribed dose (AOR = 1.9; 95% CI, 1.03 to 3.5)
  • Parents who reported their dose using teaspoon or tablespoon units were more likely to use a nonstandard instrument than those who used ml.
  • Parents using a nonstandard instrument had more than twice the odds of making an error in measurement compared with both their intended (AOR = 2.4; 95% CI, 1.1 to 5.0) and prescribed (AOR = 2.6; 95% CI, 1.2 to 5.5) doses.

 

How did the researchers interpret the results?

The researchers conclude that their findings "support a millilitre-only standard to reduce medication errors”. 

 

Conclusion

This US cross-sectional study has found that parent dosing errors of medications for children are common. Around one in six parents use a kitchen spoon rather than a standard measurement instrument to measure out liquid medicines.

It also found that errors were less common when the unit of measurement was ml rather than teaspoon/tablespoon.

A limitation of this study was that parents were assessed between four days and eight weeks after the end of the child’s prescribed medication course, meaning that memory could have had an impact. There is also the possibility that the accuracy was actually even worse than they observed, as the parents are likely to have been paying full attention to measuring the medication during the supervised assessment, rather than having distracting children around. There would also be a likelihood that they would not have wanted to “fail” the test.

In addition, as this is a cross-sectional study, it cannot show that the unit of measurement caused the errors in measurement.

However, overall, the main findings of the study would certainly seem to support the researchers’ call for a standard unit of measurement to avoid potential confusion.

In the UK, many of the leading manufacturers of liquid medication for children provide oral syringes or droppers with the medication, so this may be less of a problem than in the US.

If in doubt about any aspect of the use of children’s medication, ask your pharmacist for advice.

Analysis by
Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter. Join the Healthy Evidence forum.

Links To The Headlines

Why a spoon WON'T help the medicine go down: Risk of dosage mistakes is 50% higher, doctors warn. Daily Mail, July 15 2014

Links To Science

Yin HS, Dreyer BP, Ugboaja DC, et al. Unit of Measurement Used and Parent Medication Dosing Errors. Pediatrics. Published online July 14 2014

Categories: Medical News

Sex addiction affects brain in 'same way as drugs'

Medical News - Mon, 07/14/2014 - 18:19

“Is compulsive sexual behaviour comparable to drug addiction?” asked The Guardian today.

This and other related headlines came from a UK study that looked at brain scans of 19 men with compulsive sexual behaviour (CSB) while they watched either sexually explicit, erotic or non-sexual videos.

CSB is a not a well-established diagnosis as it does not have a formal, universally accepted, definition. It has been described as the inability to control the sexual urges, behaviour or thoughts, often with negative consequences for the individual concerned.

Examples given in the study include spending large amounts of money on escort services and losing a job due to viewing pornography at work.

The study indicated that some areas of the brain were activated more when viewing sexually explicit content in men with CSB than in similarly aged men without the disorder.

Given the pattern of brain activity and other ratings of desire, the researchers indicated that the behaviour showed similarities with drug addiction. However, this comparison was theoretical and was not actually tested in this study.

The research did not involve many men, so the results cannot be taken as definitive. Research in larger groups will be needed to confirm these initial observations and to increase confidence that the observations are true in more general terms.

It is hoped that these initial investigations will give addiction researchers some focus for future research into the condition, which has been poorly studied.

 

Where did the story come from?

The study was carried out by researchers from the University of Cambridge and was funded by the Wellcome Trust, National Institutes for Health (US) and the National Centre for Responsible Gaming.

The study was published in the peer-reviewed medical journal PLOS One. This is an open-access journal, so the study is free to read online.

Generally, the media reported the facts of the study accurately. The Guardian provided especially useful background context on the issue of CSB and pornography.

 

What kind of research was this?

This was a human study investigating the brain activity of men who had compulsive sexual behaviour.

CSB was described in the paper as excessive or problematic engagement in sex, which has also been described as “sex addiction”. Like other compulsive disorders, this is far more than just enjoying sex a lot.

It is described as the inability to control sexual urges, behaviours or thoughts, which often has a detrimental effect on the person’s life, such as not being able to engage in stable relationships.

They may not actually want or enjoy what they are doing. The researchers suggest CSB may have common brain signals and networks as other natural and drug addictions. The researchers say little is known about how the brain reacts to sexually explicit material in individuals with CSB and those without – so the researchers decided to find out.

Studying brain activity is a common tool for indicating which areas of the brain are triggered and active during different stimuli. During the scans, researchers see areas of the brain light up corresponding to activity and, depending on the area, can infer whether this is in areas of reward, fear, excitement and other emotions and responses.

 

What did the research involve?

Researchers scanned the brains of 19 men with CSB while watching videos – some sexually explicit, some erotic and others non-sexual – to compare the brain activity in each scenario. They also asked the men to rate their sexual desire and whether they liked the videos. The same experiment was carried out with 19 age-matched healthy volunteers without CSB, to act as a comparison group.

Men with CSB were recruited via internet-based advertisements or referrals from therapists, and were interviewed by a psychiatrist to ensure that they met diagnostic criteria for the disorder. They were aged over 18 (with an average age of 25.6 years), heterosexual and free from any other compulsive disorders or serious mental health issues. The men filled in questionnaires assessing their impulsivity, depression, anxiety, alcohol dependence and intelligence. Age-matched heterosexual males without CSB were recruited by community advertisement.

Two of the 19 CSB subjects were taking antidepressants or had coexisting generalised anxiety disorder and social phobia (two of them), social phobia (one of them), or a childhood history of ADHD (one of them). One man with CSB and one healthy volunteer used cannabis intermittently.

The team used functional magnetic resonance imaging to observe changes in brain activity while the men watched the videos.

 

What were the basic results?

There were both similarities and differences in the brain responses of men with CSB and those without. Sexual desire or watching of the explicit sexual videos was linked to activation in a part of the brain called dACC ventral striatal-amygdala functional network across both groups. However, it was more strongly activated and linked to sexual desire in the CSB group.

Sexual desire ratings to explicit videos were greater in men with CSB compared to healthy volunteers, but not to erotic cues, whereas liking ratings to erotic cues were greater in CSB compared to healthy volunteers, but not to explicit cues. This showed that men’s rating of desire and liking were not always related.

The researchers said that the dissociation between desire and liking is consistent with theories of motivation underlying CSB seen in drug addictions.

 

How did the researchers interpret the results?

The researchers highlighted similarities between the brain activity they had observed in men with CSB and similar findings from other research in the brains of drug addicts.

 

Conclusion

This observational study used the brain scans of 19 men with CSB to point to some areas of the brain that were activated more when viewing sexually explicit content, compared with men without the compulsive behaviour.

There were many similarities between the brains and responses of men with and without CSB, indicating that the distinction was complex and overlapping. However, some areas were identified as being more active in men with CSB. This gives researchers in the field of addiction a better focus for future research.

The research did not compare the brains of men with CSB to those people with substance misuse, or those with other forms of addiction (such as gambling), to look for differences directly. These comparisons were theoretical and were not tested empirically in this study.

Given the research involved so few men, the results cannot be taken as definitive. More research in larger groups will be needed to confirm these initial observations and to increase confidence that the observations are true in more general terms.

It is important to note that there is no formal diagnostic criteria for CSB, and there is debate as to whether it should be labelled as a condition.

Similar debate has surrounded other addictive behaviour associated with excessive or compulsive use of the internet or computer games.

Research like this is important in understanding the brain biology and the psychological processes behind this behaviour – which often has a negative impact on a person’s life.

If you are concerned that a preoccupation with sex or sexual content online may be having a negative impact on your life, it is reassuring to know that there is help available.

It may be useful to discuss the issue with your GP. The Sex and Love Addicts Anonymous website also provides information on sexually compulsive behaviours. 

Analysis by Bazian. Edited by NHS ChoicesFollow Behind the Headlines on TwitterJoin the Healthy Evidence forum.

Links To The Headlines

Is compulsive sexual behaviour comparable to drug addiction? The Guardian, July 14 2014

Scientists probe 'sex addict' brains. BBC News, July 12 2014

Love is the drug, scientists find. The Daily Telegraph, July 11 2014

The brain on porn: Researchers find sex addicts get the same high as a drug addict getting a hit. Daily Mail, July 12 2014

Links To Science

Voon V, Mole TB, Banca P, et al. Neural Correlates of Sexual Cue Reactivity in Individuals with and without Compulsive Sexual Behaviours. PLOS One. Published online July 11 2014

Categories: Medical News

'Exercise may help prevent Alzheimer's disease'

Medical News - Mon, 07/14/2014 - 14:17

"Cut Alzheimer's risk by walking," the Daily Mail recommends. This advice is prompted by a statistical modelling study looking at population attributable risks (PARS) – factors known to influence the prevalence of a disease, such as Alzheimer's, at a population level.

The seven risk factors researchers looked at included diabetes, smoking, high blood pressure, lack of exercise, obesity, depression and low educational level. In theory, some cases of Alzheimer's disease might be prevented by reducing these risk factors.

For example, the study estimated physical inactivity accounted for 21.8% of the risk of developing Alzheimer's in the UK. Another way of saying this is that if nobody was inactive, the risk of Alzheimer's in the UK population could reduce by 21.8%.

But this is only a theory that applies to an entire population, not individuals. We cannot say for sure that living a healthier life will definitely prevent Alzheimer's disease.

One of the biggest risk factors for Alzheimer's is age, and it is possible age will interact with the seven modifiable factors over different stages of a person's life. This could create a more complex risk profile than the current study was able to describe.

But a healthy lifestyle does have other benefits – regular exercise can reduce your risk of developing heart disease and some types of cancer.

 

Where did the story come from?

The study was led by researchers from the psychology department at the Institute of Psychiatry, King's College London, and was funded by an award from the National Institute for Health Research Collaboration for Leadership in Applied Health Research and Care for Cambridgeshire and Peterborough.

It was published in the peer-reviewed journal, The Lancet Neurology.

The UK media's reporting was generally accurate, with most focusing on the physical activity risk, which was the most important factor for the UK data.

 

What kind of research was this?

This modelling study used existing data on potential risk factors for developing Alzheimer's disease, including sociodemographic and lifestyle factors, and health-related factors such as diabetes and high blood pressure.

The researchers then predicted the amount of disease that might be prevented if these risk factors were reduced through changes in lifestyle.

While this type of research can provide useful predictions, they are just that – hypothetical predictions.

Similarly, the predictions apply to entire populations of people, such as everyone in UK. This means the study cannot say that living a healthier life will prevent Alzheimer's for any specific individual, only that it may prevent some cases across the group as a whole. 

 

What did the research involve?

The researchers used existing population-based research to identify the main modifiable risk factors that may be associated with Alzheimer's disease.

They then predicted how many cases of Alzheimer's disease might be prevented if the risks were reduced across the US, the UK and the rest of the world.

The main analysis was the calculation of the population attributable risk, or PAR. This is the proportion of cases of a disease in a population that is attributable to the risk factor.

A modifiable risk factor, such as smoking, is a risk you can potentially reduce – for example, by stopping smoking. The main modifiable risk factors linked to developing Alzheimer's disease were:

  • diabetes – adult prevalence of diagnosed diabetes between the ages of 20 and 79
  • midlife high blood pressure – adult midlife prevalence of hypertension between the ages of 35 and 64
  • midlife obesity – adult midlife prevalence of body mass index greater than 30 between the ages of 35 and 64
  • physical inactivity – proportion of adults who do not do either 20 minutes of vigorous activity on three or more days, or 30 minutes of moderate activity on five or more days per week
  • depression – lifetime prevalence of major depressive disorder using Diagnostic and Statistical Manual of Mental Disorders or International Classification of Diseases criteria
  • smoking – the proportion of adult smokers
  • low educational level – the proportion of adults with an International Standard Classification of Education level of two or less (pre-primary, primary and lower secondary education)

The researchers made projections for the number of cases of Alzheimer's disease up to the year 2050. They then modelled risk reductions of 10% and 20% for each decade from now until 2050 to see how many disease cases could be prevented.

They did this for each risk factor both individually (to see which ones had the biggest impact) and combined.

The predictions took account of associations between risk factors – for example, that a person who is obese is more likely to have high blood pressure.

 

What were the basic results?

The study calculated PAR for the world, the US and the UK. We focus on the UK results below.

The largest PAR for an individual risk factor in the UK was for physical inactivity (PAR 21.8% 95% confidence interval [CI], 6.1% to 37.7%).

This meant that 21.8% of the Alzheimer's cases were predicted to be attributable to physical inactivity, which could potentially be prevented if people were more active.

The next highest PAR was for low educational level (PAR 12.2% 95% CI, 7.6% to 16.9%), followed by smoking (10.6%, 95% CI, 2.9% to 19.4%).

Diabetes, midlife hypertension, midlife obesity and depression gave PARs in the range of 1.9% to 8.3%.

Combining the seven risk factors together gave a UK PAR of 30.0% (95% CI, 14.3% to 44.4%).

This means the researchers predicted around 30.0% of the risk of developing Alzheimer's disease in the UK was attributable to a combination of these seven modifiable risk factors.

This estimate adjusted for associations between risk factors, such as obesity and diabetes.

 

How did the researchers interpret the results?

The researchers concluded that, "After accounting for non-independence between risk factors, around a third of Alzheimer's diseases cases worldwide [and in the UK] might be attributable to potentially modifiable risk factors.

"Alzheimer's disease incidence might be reduced through improved access to education and use of effective methods targeted at reducing the prevalence of vascular risk factors [for example, physical inactivity, smoking, midlife hypertension, midlife obesity and diabetes] and depression."

 

Conclusion

This study suggests around a third of the risk of developing Alzheimer's disease might be caused by a combination of seven lifestyle-related risk factors, including low educational level, physical inactivity and smoking. In theory, by reducing these risk factors some cases of Alzheimer's disease might be prevented.

Predictive studies such as this one are only as good as the assumptions and data used in the calculations. As the researchers themselves acknowledge, despite their best efforts to the contrary, this still involves "substantial uncertainty". Consequently, there may be some variation in the estimates of the PARs presented because of potential inaccuracies or natural variations in prevalence data.

The strength of the association between the risk factor and the disease may also vary in different groups. This accuracy could be tested by repeating the research using a range of different data sources and assumptions. 

The predictions this study makes apply to entire populations of people, such as everyone in the UK. It therefore cannot say that living a healthier life will definitely prevent Alzheimer's for any specific individual, only that it may reduce the risk and prevent some cases across the group as a whole.

If everyone in the UK was physically active (defined in this study as 20 minutes of vigorous activity on three or more days a week, or 30 minutes of moderate activity on five or more days a week) the study predicts around 20% of the risk of developing Alzheimer's would be cut, which would reduce the number of people developing the disease overall.

But because we are modelling the effect in large groups, it is not possible to pinpoint which people would get Alzheimer's and which would not. Other types of test and analysis would need to be developed to be able to predict this.

These predictions assume that all the risk factors tested directly cause or contribute to Alzheimer's disease. The researchers acknowledge this is open to debate in some areas. This means the risk accounted for by these factors could potentially be lower than estimated in this study.

One of the biggest risk factors for Alzheimer's disease is age, and it is likely age will interact with the seven modifiable factors over different stages of a person's life, creating a more complex risk profile than this study was able to describe.

For example, it is unlikely that someone who decides to quit smoking and start exercising regularly at 20 would have the same risk reduction as someone deciding the same thing at 70.

Nonetheless, there are a host of other good reasons for leading a healthy lifestyle, no matter what your age. Keeping active once you reach retirement age can also help you stay more energetic, healthy and independent as you get older.

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter. Join the Healthy Evidence forum.

Links To The Headlines

Cut Alzheimer's risk by walking: It only takes 20 minutes, 3 times a week, say Cambridge scientists. Daily Mail, July 14 2014

One in three Alzheimer's cases preventable, says research. BBC News, July 14 2014

The key to reducing risk of Alzheimer's unlocked – and the answer is exercise. Metro, July 14 2014

One hour of exercise a week 'can halve dementia risk'. The Daily Telegraph, July 13 2014

Third of Alzheimer's cases could be 'preventable'. ITV News, July 14 2014

How to beat Alzheimer's: Exercise & better education can ward off dementia, experts claim. Daily Express, July 14 2014

Links To Science

Norton S, Matthews FE, Barnes DE, et al. Potential for primary prevention of Alzheimer's disease: an analysis of population-based data. The Lancet Neurology. Published online July 13 2014 

Categories: Medical News

Offer weight loss surgery to diabetics, says NICE

Medical News - Fri, 07/11/2014 - 14:30

"An expansion of weight loss surgery in England is being proposed to tackle an epidemic of type 2 diabetes," BBC News reports. The National Institute for Health and Care Excellence (NICE) has recommended obese people with type 2 diabetes should be offered weight loss (bariatric) surgery.

These draft guidelines include new recommendations about the treatment of obesity. In particular, NICE advises that those with recent-onset type 2 diabetes who fulfil certain body mass index (BMI) criteria should have surgery. The recommendations also provide guidance on the use of very low-calorie diets.

As is often the case, the proposed NICE recommendations have made a huge media splash, leading to front-page headlines such as the Daily Mail's claim that, "Thousands more to get obesity ops on the NHS".

These are draft guidelines, so it is far from certain whether they will become official advice. A consultation will be taking place between July 11 and August 8 2014.

 

What are the main new draft guidelines?

Currently, bariatric surgery is offered to people with a BMI of 40 or more, or those with a BMI between 35 and 40 if they also have another significant and possibly life-threatening disease that could be improved if they lost weight, such as type 2 diabetes or high blood pressure.

Patients must have tried and failed to achieve clinically beneficial weight loss by all other appropriate non-surgical methods and be fit for surgery. This recommendation has not changed.

The updated draft guidelines include additional recommendations on bariatric surgery for people with recent-onset type 2 diabetes. These recommendations include:

  • Offering an assessment for bariatric surgery to people who have recent-onset type 2 diabetes and are also obese (BMI of 35 and over).
  • Considering an assessment for bariatric surgery for people who have recent-onset type 2 diabetes and have a BMI between 30 and 34.9. People of Asian origin will be considered for surgery if they have a lower BMI than this, as the point at which the level of body fat becomes a health risk varies between ethnic groups. Asian people are known to be particularly vulnerable to the complications of diabetes.

 

What is bariatric surgery?

Bariatric surgery includes gastric banding, gastric bypass, sleeve gastrectomy and duodenal switch.

A range of techniques are used, but they are usually all based on the principle of surgically altering the digestive system so it takes less food and makes the patient feel fuller quicker after eating.

The two most common types of weight loss surgery are:

  • gastric band – where a band is used to reduce the size of the stomach so a smaller amount of food is required to make someone feel full
  • gastric bypass – where the digestive system is rerouted past most of the stomach so less food is digested, which makes the person feel full

These procedures are usually performed using keyhole surgery.

 

What are the risks?

As with all types of surgery, weight loss surgery carries a risk of complications. These include:

  • internal bleeding
  • a blood clot inside the leg (deep vein thrombosis)
  • a blood clot or other blockage inside the lungs (pulmonary embolism)

It is estimated the risk of dying shortly after gastric band surgery is around 1 in 2,000. A gastric bypass carries a higher risk of around 1 in 100.

The surgery also carries the risk of other side effects, including:

  • excess skin – removal of excess skin is usually considered a form of cosmetic surgery, so it is not usually available on the NHS
  • gallstones – small stones, usually made of cholesterol, that form in the gallbladder
  • stomal stenosis – where the hole that connects the stomach to the small intestine in people with a gastric bypass becomes blocked
  • gastric band slippage – where the gastric band slips out of position
  • food intolerance
  • psychosocial effects – for example, some people have reported relationship problems with their partner because their partner begins to feel nervous, anxious or possibly jealous of their weight loss

 

What other treatments have new draft recommendations?

The draft guideline also makes recommendations regarding very low-calorie diets (800kcal per day or less). These include:

  • Not routinely using very low-calorie diets to manage obesity.
  • Only considering very low-calorie diets for a maximum of 12 weeks (continuously or intermittently) as part of a multicomponent weight management strategy with ongoing support. This would be for people who are obese and have a clinically assessed need to rapidly lose weight – for example, people who require joint replacement surgery or who are seeking fertility services.
  • Giving counselling and assessing people for eating disorders or other mental health conditions before starting them on a very low-calorie diet. This is to ensure the diet is appropriate for them.

The risks and benefits of surgery should also be discussed. Patients should be made aware that very low-calorie diets are not a long-term weight management strategy and that regaining weight is likely, but not because of a failure on their or their clinician's part.

 

How were the draft recommendations received?

There is concern about how many people will be eligible for treatment under the new guidelines and how much it will cost, with Diabetes UK estimating that 850,000 people could be eligible for surgery.

Simon O'Neill, from the charity Diabetes UK, has been quoted as saying that, "Bariatric surgery should only be considered as a last resort if serious attempts to lose weight have been unsuccessful and if the person is obese.

"It can lead to dramatic weight loss, which in turn may result in a reduction in people taking their type 2 diabetes medication, and even in some people needing no medication at all.

"This does not mean, however, that type 2 diabetes has been cured. These people will still need to eat a healthy balanced diet and be physically active."

 

What is the rationale behind the new recommendations regarding bariatric surgery?

Professor Mark Baker, director of the Centre for Clinical Practice, said that, "Updated evidence suggests people who are obese and have been recently diagnosed with type 2 diabetes may benefit from weight loss surgery.

"More than half of people who undergo surgery have more control over their diabetes following surgery and are less likely to have diabetes-related illness; in some cases, surgery can even reverse the diagnosis. The existing recommendations around weight loss surgery have not changed."

It could actually be the case that increasing access to bariatric surgery will save the NHS money in the long term if this helps combat the obesity epidemic.

If obesity levels continue to rise at their current rates, it is estimated that by 2050 the annual cost of treating obesity-related complications will be £50 billion, more than half the entire current NHS budget for England.

One million operations at £5,000 each – £5 billion in total – could well seem a bargain in comparison.

Analysis by
Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter. Join the Healthy Evidence forum.

Links To The Headlines

More weight loss operations for diabetes. BBC News, July 11 2014

Thousands more to get obesity ops on the NHS: NICE calls for huge increase in surgery – but even obesity charities condemn it. Daily Mail, July 11 2014

Give weight-loss surgery to obese patients on NHS to curb diabetes, says Nice. The Independent, July 11 2014

NHS anti-obesity plans could lead to sharp rise in gastric band surgery. The Guardian, July 11 2014

Thousands more diabetics to be offered weight loss surgery on the NHS. Daily Mirror, July 11 2014

Weight loss surgery can 'reverse diabetes diagnosis'. ITV News, July 11 2014

Obesity surgery could be offered to a million more people on NHS. The Daily Telegraph, July 11 2014

NHS plans to tackle diabetes crisis with FREE stomach stapling and gastric bands. Daily Express, July 11 2014

Categories: Medical News

Vasectomy-associated prostate cancer risk 'small'

Medical News - Fri, 07/11/2014 - 14:26

“Men who have the snip increase their risk of suffering fatal prostate cancer, according to research,” the Daily Mail reports. However, while the increase in risk was found to be statistically significant, it was small in absolute terms.

The newspaper reports on a US study that followed 49,405 men over 24 years, a quarter of whom had had a vasectomy.

It compared the risk of prostate cancer in men who had a vasectomy to the men who hadn’t.

During the 24 years of this study, 12.4% of those who had had a vasectomy developed prostate cancer, compared with 12.1% of those who hadn’t.

They also found vasectomy to be associated with a 19% increased risk of prostate cancer that had spread to other organs (metastatic) or that caused death.

However, it’s important to note that these increases in relative risk relate to a small increase in terms of absolute risk (a 0.3% absolute difference in incidence rate).

This type of study also cannot show that vasectomies cause prostate cancer, as there could have been differences in the men that opted for vasectomy that the researchers did not adjust for.

Overall, though the study findings are worthy of further research, men should not be overly concerned by these reports.

 

Where did the story come from?

The study was carried out by researchers from Brigham and Women’s Hospital, Harvard School of Public Health, the Dana Farber Cancer Institute and the University of Massachusetts Medical School. It was funded by the US National Cancer Institute/National Institutes of Health.

The study was published in the peer-reviewed Journal of Clinical Oncology.

The results of the research were mainly well reported. To give credit to the UK media, some of the news sources which covered the study made it clear that the increase in absolute risk is small (something that is often not made clear in health reporting).

One point to mention is that The Guardian and The Daily Telegraph both said that men who had vasectomies at a younger age were at the greatest risk, though this is not supported by the results of the study.

It was suggested in the research paper that the increased risk was more pronounced among men who were younger at the time of vasectomy. However, this association was not statistically significant, so it could have been due to chance.

 

What kind of research was this?

This was a cohort study that aimed to investigate the association between vasectomy and prostate cancer risk.

A cohort study is the ideal study design to address this question. However, cohort studies cannot show causation, as there is the potential for confounders (other variables that explain the association).

 

What did the research involve?

The researchers studied 49,405 men who were part of the Health Professionals Follow-Up Study, which is an ongoing cohort study conducted by Harvard University.

The men were aged between 40 and 75 years old at the start of the study in 1986. They were followed-up for 24 years, until 2010. Around a quarter of the men (12,321) had vasectomies.

During the follow-up period, 6,023 men were diagnosed with prostate cancer, and 811 men died from prostate cancer.

The researchers compared the risk of developing prostate cancer in men with a vasectomy to the risk of prostate cancer in men without a vasectomy.

This was to see if having a vasectomy was associated with an increased risk of prostate cancer.

The researchers adjusted their analyses for a number of confounders, including:

  • age
  • height
  • body mass index (BMI)
  • amount of vigorous physical activity
  • smoking status
  • diabetes
  • whether the men had a family history of prostate cancer
  • multivitamin use
  • vitamin E supplement use
  • alcohol intake
  • history of prostate-specific antigen (PSA) testing

PSA is a protein produced by normal cells in the prostate and also by prostate cancer cells, and elevated levels can indicate a variety of prostate problems (for example, levels are raised with cancer, but also benign enlargement, inflammation and infection).

 

What were the basic results?

During the study 12.4% of those who’d had a vasectomy developed prostate cancer (1,524 cases out of 12,321 who’d had a vasectomy) compared with 12.1% of those who hadn’t (4,499 cases out of 37,804 who hadn’t had a vasectomy).

The researchers found that vasectomy was associated with:

  • A 10% increase in risk of prostate cancer (relative risk [RR] 1.10, 95% confidence interval [CI] 1.04 to 1.17).
  • A 22% increase in risk of “high-grade” cancer (more aggressive cancer with poorer prognosis) (RR 1.22, 95% CI 1.03 to 1.45). High-grade cancer was defined as having a Gleeson score of 8 to 10 at diagnosis.
  • A 20% increase in risk of “advanced prostate cancer” (lethal or stage T3b [cancer had spread to the seminal vesicles], T4 [cancer has spread to nearby organs], N1 [lymph nodes contain cancer cells] or M1 [cancer has spread to other parts of the body]) (RR 1.20, 95% CI 1.03 to 1.40). 
  • A 19% increase in risk of prostate cancer with distant metastasis (where the cancer has spread to another part of the body) or that causes death (RR 1.19, 95% CI 1.00 to 1.43).

The researchers noted that men who had a vasectomy reported more PSA testing than men without vasectomy.

Although the researchers adjusted for frequency of testing in their analyses, they were concerned the results could be due to men with vasectomy being diagnosed with prostate cancer because they had PSA testing more frequently, rather than because they were more likely to have prostate cancer.

They then performed an analysis of “highly screened” men (who reported PSA screening in 1994 and 1996; note this is a US study and there is no national PSA screening campaign in the UK).

In this subcohort, having a vasectomy was not associated with increased risk of prostate cancer overall, but the association with cancer with distant metastasis or that causes death remained. 

 

How did the researchers interpret the results?

The researchers concluded that their data “support the hypothesis that vasectomy is associated with a modest increased incidence of lethal prostate cancer.”

 

Conclusion

This 24-year cohort study found that men with a vasectomy had a 10% increased risk of prostate cancer and a 19% increased risk of prostate cancer that had spread to other organs, or that caused death.

However, it’s important to note that there are only tiny increases in absolute risk; during the 24 years of this study, 12.4% of those who’d had a vasectomy developed prostate cancer, compared with 12.1% of those who hadn’t.

The strengths of this study are its large size, its long follow-up period, and the collection of data on and adjustment for a large number of factors that could affect the association (confounders). However, as this is a cohort study, it cannot show causation, as the potential for other confounders remains.

Given that the 0.3% absolute difference in cancer incidence is small, there may be other factors differing between those who had a vasectomy and those that didn’t that could account for the differences.

Overall, though the study finding is worthy of further research, men should not be overly concerned by these findings.

As the researchers say, “the decision to opt for a vasectomy remains a highly personal one in which the potential risks and benefits must be considered.”

There are also less drastic steps you can take if you don’t want to have any children.

If used correctly, condoms are 98% effective. They also have the advantage of protecting you against sexually transmitted infections (STIs).

And there is always the possibility that you may change your mind about having children. Vasectomy reversal is expensive (it is rarely available on the NHS) and has a patchy success rate, ranging from 25% to 55%.

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter. Join the Healthy Evidence forum.

Links To The Headlines

Men opting for the snip could be at greater risk of prostate cancer: Vasectomy linked to most lethal form of the disease, study finds. Daily Mail, July 11 2014

Vasectomy can increase risk of developing lethal prostate cancer. The Daily Telegraph, July 10 2014

Having a vasectomy raises risk of prostate cancer by 10 per cent, claims new study. The Independent, July 10 2014

Prostate cancer danger raised if you have 'snip'. Daily Mirror, July 11 2014

Vasectomy raises risk of lethal prostate cancer, study shows. The Guardian, July 11 2014

Links To Science

Siddiqui MM, Wilson KM, Epstein MM, et al. Vasectomy and Risk of Aggressive Prostate Cancer: A 24-Year Follow-Up Study. Journal of Clinical Oncology. Published online July 7 2014

Categories: Medical News

Obesity link for siblings

Medical News - Thu, 07/10/2014 - 18:00

“Children are five times more likely to become obese if their older brother or sister is overweight,” reports the Daily Mail.

There is a widespread assumption that a significant risk factor for child obesity is if they have one or both parents who are obese.

A new US study suggests that a more influential risk factor may be if a child has a brother or sister (or both) who are obese. 

A study of US families has found that among those with two children, if one child was obese then there was a relatively large chance that the other child would also be obese.

This “obese sibling” effect was particularly pronounced if the children are of the same gender. This study has several limitations, including its reliance on one parent self-reporting the height and weight of both themselves and their children.

The study also relied on data taken at one point in time, so it cannot prove a direct cause and effect.

It does arguably highlight the fact that a family environment can play an important part in influencing individual family member’s health outcomes. 

Often, the family that exercises and eats healthily together, achieves a healthy weight together.

Read more about exercising as a family.

 

Where did the story come from?

The study was carried out by researchers from Massachusetts General Hospital, MassGeneral Hospital for Children, Harvard Medical School, the National Bureau of Economic Research, Cornell University and Duke University, all in the US. It was funded by the Robert Wood Johnson Foundation.

The study was published in the peer-reviewed American Journal of Preventive Medicine.

The study is open-access, so is available online free of charge.

The Mail Online’s reporting that children are five times more likely to become obese if their older brother or sister is overweight was a little skewed. It implied that older siblings influence younger children’s eating and exercise behaviour.

But this study had a cross-sectional design, which means all the data was gathered at the same time, so we cannot be sure whether one factor (such as an older sibling’s obesity) follows another (a younger sibling's obesity).

In some cases, the younger sibling may have be the first to develop obesity, followed by the older sibling.

As the study makes clear, older children were five times as likely to be overweight if their younger sibling was also obese.

 

What kind of research was this?

This was a cross-sectional study looking at how the obesity status of different children within the same family is related to parental or other sibling obesity.

The researchers point out that while the parent-child obesity link is well established, little is known about any association in obesity status between siblings. 

They also say that unhealthy behaviours of children are shaped by the family and peer environment, school and neighbourhood – factors which together may influence sibling health differently than parental health.

Cross-sectional studies look at all data at the same time, so they cannot be used to see if one thing follows another, but are useful for showing up patterns or links in the data.

 

What did the research involve?

In 2011 the researchers contacted adults in 14,400 US households in a web-based survey about family health habits, using the resources of a national market research company. Of the 14,400, 71% (10,244 households) responded.

To take part in this aspect of the larger study, adults had to have either one or two children under 18 years of age who were living at home. Participants completed a survey on family health habits via the internet, as well as data on socioeconomic status, physical activity and overall health and “food environment”.

The questions were adapted from a variety of validated sources.

The responding adult also had to report height and weight for themselves and their children. Of the households asked, 1,948 adults had the required one or two children; provided the information needed and reported on adult and child height and weight.

From the information on height, weight and gender, researchers classified adults and their children as obese or not obese.

For children they also used information on age and growth chart data, classifying them according to internationally accepted criteria to measure obesity in children.

For adults they calculated the body mass index (BMI) from self-reported height and weight.

They analysed the association between obesity in a child and obesity in his or her siblings and parents. They adjusted the results for a range of possible factors that might influence results (called confounders).

 

What were the basic results?

The researchers found that:

  • In one-child households, a child was 2.2 times more likely to be obese if a parent was obese (standard deviation 0.5).
  • In households with two children, having an obese younger sibling was more strongly associated with the elder child’s obesity (odds ratio [OR] 5.4, SE.9) than a parent’s obesity status (OR 2.3, SE 0.8).
  • Having an obese elder sibling was associated with a younger child’s obesity (OR 5.6, SE 1.9), and the parent’s obesity status was no longer significant.
  • The link between siblings and obesity was stronger when they were the same gender.
  • Child physical activity was significantly associated with obesity status.

Surprisingly, they also found that having an extremely active older sibling was associated with a higher risk of younger sibling obesity.

 

How did the researchers interpret the results?

The researchers say that siblings may have greater influence on informal behaviour than parents and that older siblings may influence their younger siblings’ attitude and behaviours around food and physical activity. Taking sibling information into account may be of benefit in efforts to prevent childhood obesity, they argue.

 

Conclusion

This study found that while parent obesity made it more likely that a child would be obese, in two-child families, sibling obesity had an even stronger association.

However, as the authors point out, the study has several limitations.

  • It was based on self-reported data on height and weight and proxy reports for children, which limits its reliability.
  • Its cross-sectional design means all the data was gathered at the same time, so we cannot be sure whether one factor (such as an older sibling’s obesity) follows another (a younger sibling's obesity). 
  • It was not a representative sample of the US population, which has a higher prevalence of childhood obesity.
  • It was restricted to families with only one or two children. Different results may be found in larger families.
  • Importantly, it included only the obesity status of one adult in each household – the one who responded to the survey.

Obesity is a major global health problem in which many factors play a part, including social and food environment, family lifestyle and shared genetic background.

It is likely that siblings have a common exposure to many such factors.

It is also possible that siblings influence each other’s behaviour around food and physical activity, but this study is not strong enough to prove it. 

Read more advice about what to do if your child (or children) is overweight, or very overweight.

Your GP should also be able to provide advice.

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter. Join the Healthy Evidence forum.

Links To The Headlines

Children with obese siblings are FIVE times more likely to become overweight... but healthy friends could help beat the bulge. Mail Online, July 9 2014

Links To Science

Pachucki MC, Lovenheim MF, Harding M. Within-Family Obesity Associations - Evaluation of Parent, Child, and Sibling Relationships. American Journal of Preventive Medicine

Categories: Medical News

Malaria parasites can 'hide' inside bone marrow

Medical News - Thu, 07/10/2014 - 14:30

“Malaria parasites can hide inside the bone marrow and evade the body's defences, research confirms,” BBC News report.

It is hoped that this insight into the activities of the parasites could lead to new treatments.

While most people associate malaria with mosquitoes, the disease is actually caused by tiny parasites called Plasmodium, which infect mosquitoes and spread the infection to humans by injecting them with spores.

These spores grow and multiply in the liver and then infect blood cells, causing the symptoms of malaria.

To continue their lifecycle, some of the parasites sexually mature and are then transferred back into mosquitoes during another bite, where they can breed. 

The researchers looked at tissue samples from autopsies of children who had died from malaria.

The study found evidence that sexual maturation of the parasite is likely to take place in the bone marrow, but outside of the blood vessels. This might be why the immune system rarely destroys them, as infection-fighting antibodies are unable to target bone marrow tissue.

It is hoped that these results can pave the way for the development of new drugs to target this key stage. This has the potential to reduce the number of infected mosquitoes, thus decreasing the number of malaria cases.

The ultimate hope is that malaria could be eradicated in the same way as smallpox.

 

Where did the story come from?

The study was carried out by researchers from around the globe, including the Harvard School of Public Health, the Liverpool School of Tropical Medicine, the University Of Malawi College Of Medicine, and Brigham and Women’s Hospital, Boston. It was funded by the US National Institutes of Health.

The study was published in the peer-reviewed medical journal Science Translational Medicine.

The study was briefly reported by BBC News, which provided an accurate summary of the research.

 

What kind of research was this?

This was an autopsy study designed to investigate where a key stage in the lifecycle of the parasite that causes malaria takes place.

The tropical disease is caused by Plasmodium parasites. The most severe form of malaria is caused by Plasmodium falciparum. The lifecycle of the parasite relies on blood-feeding mosquitoes and humans. When an infected mosquito bites a human, sporozoites are injected into the human, and they travel to the liver. They mature into schizonts in the liver and then rupture to release meroziotes into the blood. These merozoites divide and multiply asexually by sticking to the sides of small blood vessels. This process causes the symptoms of malaria, which include shivering and fever.

However, for the parasites to continue their lifecycle, some of the meroziotes mature into the sexual stage; these are called gametocytes. These male and female gametocytes are then ingested by mosquitoes the next time they have a blood meal; they can then fertilise and replicate within the mosquito.

The gametocytes are only present in the bloodstream when they are mature enough to be taken up by mosquitoes. They take six to eight days to mature, and it is believed this takes place in human tissue. This stage has not been studied in depth, as the Plasmodium falciparum will only live in humans, so rodent studies are not possible. This study looked for these immature gametocytes in multiple tissue sites in autopsies of children who had died from malaria, to find out where this stage takes place.

 

What did the research involve?

The researchers initially used antibodies to identify the parasite in general, as well as specific antibodies to the sexual gametocytes, to detect them in various tissues from six autopsies. They looked at tissue samples from eight organs and the subcutaneous fat.

They measured the total proportion of parasites in each organ compared to the level of gametocytes.

They then measured the level of gene activity of three stages in the gametocyte maturation process in the different organs, to see if the first of these stages takes place in one particular site.

The researchers then looked in detail at the bone marrow from 30 autopsies to gather more information about where the gametocytes mature.

Finally, they performed experiments with growing Plasmodium falciparum in the laboratory.

 

What were the basic results?

Results from the first six autopsies revealed that:

  • The spleen, brain, heart and gut had the highest numbers of total parasites.
  • Levels of gametocytes were high in the spleen, brain, gut and bone marrow.
  • There was a significantly higher proportion of gametocytes compared to total parasites in the bone marrow (44.9%), in comparison to the gut (12.4%), the brain (4.8%) and all other organs.
  • The first stage of gametocyte gene activity was highest in the bone marrow. 

Results from the 30 autopsies of bone marrow found that:

  • The youngest gametocytes did not stick to blood vessels as happens in the asexual reproduction of merozoites; instead, they were outside of the blood vessels in the bone marrow. 
  • Immature gametocytes appeared to grow inside young red blood cells. 

The laboratory experiments confirmed that Plasmodium falciparum gametocytes can mature inside young red blood cells.

 

How did the researchers interpret the results?

The researchers said there is evidence that gametocytes develop within the bone marrow, probably in early red blood cells, and that this process uses a different mechanism to the asexual cell replication.

This means there is potential for drugs to be developed that could target this process.

 

Conclusion

This interesting study has found evidence of the likelihood that the sexual reproductive stage in the lifecycle of Plasmodium falciparum takes place outside of the blood vessels, in the bone marrow.

It has also shown that these immature gametocytes are rarely destroyed by the immune system.

It is hoped that these results can pave the way for the development of new drugs to target this key stage in the Plasmodium falciparum lifecycle.

While this would not treat the symptoms of malaria – which come from the asexual reproduction of merozoites – it could potentially stop the transmission of the sexual gametocytes back into mosquitoes.

This could reduce the number of infected mosquitoes, thus decreasing the number of malaria cases.

Eradicating malaria is a challenge, but many public health experts think it is plausible.

For example, Microsoft founder turned philanthropist Bill Gates has pledged billions of dollars towards this goal. What impact this would have on the planet’s ecosystem is debatable.

Analysis by Bazian. Edited by NHS ChoicesFollow Behind the Headlines on TwitterJoin the Healthy Evidence forum.

Links To The Headlines

Malaria parasite 'gets down to the bone'. BBC News, July 9 2014

 

Links To Science

Joice R, Nilsson SK, Montgomery J, et al. Plasmodium falciparum transmission stages accumulate in the human bone marrow. Science Translational Medicine. Published online July 9 2014

 

Categories: Medical News

Call to tackle maternal blood infection risk

Medical News - Wed, 07/09/2014 - 14:20

“Pregnant women and new mothers need closer attention for signs of potentially fatal sepsis, a study says,” reports BBC News.

While still rare, sepsis – a blood infection – is now the leading cause of maternal death in the UK.

Sepsis can potentially be very serious, as it can cause a rapid fall in blood pressure (septic shock), which can lead to multiple organ failure. If untreated, sepsis can be fatal.

The study collected information on all cases of severe sepsis that were treated in hospital maternity units from June 2011 to May 2012.

It found there were 365 confirmed cases of severe sepsis out of over 780,000 maternities. Out of these, five women died (meaning around 0.05% of maternities were affected). 

The most common place for the infection to have spread to the blood from was the urinary and genital tract. Severe sepsis occurred rapidly, often within 24 hours of the first symptoms. Over 40% of women with severe sepsis had an illness with a high temperature, or were taking antibiotics in the previous two weeks.

This study highlights the importance of identifying infections in pregnant women and women who have recently given birth, especially in the first few days after delivery. During these periods, if you have a high temperature over 38°C or are on antibiotics but not getting better, you should seek medical attention.

 

Where did the story come from?

The study was carried out by researchers from the University of Oxford, Northwick Park Hospital, Bradford Royal Infirmary and St Michael’s Hospital in Bristol. It was funded by the National Institute for Health Research.

The study was published in the peer-reviewedopen-access medical journal PLOS Medicine, so the study can be read online for free.

BBC News reported the study accurately and provided sage advice from one of the authors, Professor Knight, who said that, “women who are pregnant or have recently given birth need to be aware that if they are not getting better after being prescribed antibiotics – for example, if they continue to have high fevers, extreme shivering or pain – they should get further advice from their doctor or midwife urgently”.

 

What kind of research was this?

This was a case-control study. The researchers studied all women in the UK diagnosed with severe sepsis (blood poisoning) during pregnancy or during the six weeks after delivery in all maternity units in the UK, from June 1 2011 to May 31 2012 (“cases”), as well as two unaffected (“control”) women per case.

Sepsis is the leading cause of maternal death in the UK, with a rate of 1.13 per 100,000 maternities between 2006 and 2008. The aim of this study was to identify risk factors, the sources of infection and type of organisms responsible, in order to improve prevention and management strategies.

A case-control study selects people with a condition, and matches each of them to at least one other person without the condition; this can be done by factors such as age and sex. In this study, controls were women who did not have severe sepsis, and delivered immediately before each case in the same hospital. Medical histories and exposures can then be compared between the cases and controls to look for associations, and thus risk factors, for the condition. This type of study is useful in investigating rare and emergency conditions, but cannot prove causation.

 

What did the research involve?

The researchers collected information from all 214 hospitals in the UK that have maternity units led by obstetricians. This included all cases of sepsis around pregnancy and two controls for each case. They compared the sociodemographic, medical history and delivery characteristics between the cases and controls. They also compared the cases that developed into septic shock with those that didn’t, to identify factors that were associated with increased severity.

 

What were the basic results?

In terms of severe sepsis cases:

  • There were 365 confirmed cases out of 780,537 maternities.
  • For most women, it was less than 24 hours between the first sign of systemic inflammatory response syndrome (SIRS) and the diagnosis of severe sepsis (SIRS is a term used to describe cases where two or more symptoms associated with sepsis are present).
  • 134 occurred during pregnancy and 231 were after delivery.
  • Those cases that occurred after delivery happened, on average, after three days.
  • 114 women were admitted to the intensive care unit (ICU).
  • 29 (8%) women had a miscarriage or a termination of pregnancy.
  • Five infants were stillborn and seven died in the neonatal period.

In terms of septic shock cases:

  • 71 (20%) of the women developed septic shock.
  • Five women died.

In terms of sources of infection:

  • A source was identified in 270 cases (70%). 
  • Genital tract infection was responsible for 20.2% of cases during pregnancy and 37.2% of cases after delivery.
  • Urinary tract infection caused 33.6% of cases during pregnancy and 11.7% of cases after delivery.
  • Wound infection caused 14.3% of cases after delivery.
  • Respiratory tract infection caused 9% of cases during pregnancy and 3.5% of cases after delivery. 

In terms of organisms responsible:

  • E. coli was the most common organism, occurring in 21.1% of infections.
  • Group A streptococcus was the next most common organism, occurring in 8.8% of infections; for most women with group A streptococcal infection, there was less than nine hours between the first sign of SIRS and severe sepsis, with half having less than two hours between the first signs and diagnosis.
  • 50% of women with group A streptococcal infection progressed to septic shock.

Risk factors for severe sepsis included women who:

  • were of black or other minority ethnic origin
  • were primiparous (giving birth for the first time)
  • had a pre-existing medical problem
  • had a febrile (high temperature) illness or were taking antibiotics in the two weeks before developing severe sepsis

All types of deliveries requiring operations were risk factors for severe sepsis. These were:

  • operative vaginal delivery
  • pre-labour caesarean section
  • caesarean section after the onset of labour

Risk factors for developing septic shock were:

  • multiple pregnancy
  • group A streptococcus

 

How did the researchers interpret the results?

The researchers concluded that “over 40% of women with severe sepsis had a febrile illness or were taking antibiotics prior to presentation, which suggests that at least a proportion were not adequately diagnosed, treated or followed up … it cannot be assumed that antibiotics will prevent progression to severe sepsis … there is a need to ensure that follow-up happens to ensure that treatment is effective”. They also recommend that “signs of severe sepsis in peripartum women, particularly with confirmed or suspected group A streptococcal infection, should be regarded as an obstetric emergency”.

 

Conclusion

This comprehensive study highlights several areas where awareness of the risks of sepsis in pregnancy should be increased in both primary and secondary care. These include:

  • If there is clinical suspicion of infection with group A streptococcus, then urgent action should be taken.
  • There should be increased care given to pregnant women and women who have just given birth who have a suspected infection.
  • High-dose intravenous antibiotics should be given within one hour of admission for suspected sepsis.
  • Vigilant infection control measures should be employed during vaginal delivery.
  • Despite antibiotics being routinely prescribed before planned caesarean sections, women are still at risk of severe sepsis and need to be closely monitored.
  • There should be consideration for clinicians to give prophylactic antibiotics before operative vaginal deliveries.
  • There should be consideration for clinicians to give prophylactic antibiotics at the time the decision is made to perform an emergency caesarean section. 

Strengths of the study include its size and the 100% participation rate of maternity units in the UK, which should account for any regional or socioeconomic differences.

If you are pregnant or have just given birth, and have signs or symptoms of infection, such as a high temperature of over 38°C, it is important to seek medical advice immediately.

Analysis by Bazian. Edited by NHS ChoicesFollow Behind the Headlines on TwitterJoin the Healthy Evidence forum.

Links To The Headlines

Blood infection warning for new mums. BBC News, July 9 2014

Links To Science

Acosta CD, Kurinczuk JJ, Lucas DN, et al. Severe Maternal Sepsis in the UK, 2011–2012: A National Case-Control Study. PLOS Medicine. Published online July 8 2014

Categories: Medical News

Cycling linked to prostate cancer, but not infertility

Medical News - Wed, 07/09/2014 - 14:17

"Men who cycle more than nine hours a week are … more likely to develop prostate cancer," the Mail Online inaccurately reports. The story comes from the publication of an online survey into cycling in the UK and its effects on health outcomes.

Researchers were particularly interested in whether frequent cycling was linked to an increased risk of prostate cancerinfertility and erectile dysfunction (impotence).

Fears have been raised regarding the effect cycling has on these conditions. These concerns have been attributed to a wide range of factors, such as repetitive trauma.

This study found no association between the amount of time spent cycling and erectile dysfunction or infertility.

But it did find a dose-response relationship between cycling time and the risk of prostate cancer in men aged over 50, with risk increasing as the hours a week spent cycling increased.

Despite these seemingly alarming results, regular cyclists do not need to panic – this type of study cannot prove increased cycling time leads to prostate cancer; it can only prove an association.

Also, the prostate cancer analyses were only carried out on fewer than 42 men, which is only a relatively small sample of men. With such a small sample, it increases the possibility that any association is the result of chance.

Most experts would agree that the health benefits of frequent cycling outweigh the risks.

For more on the pros and cons of the sport, read our special report on cycling.

 

Where did the story come from?

The study was carried out by researchers from University College London. Funding is not explicitly stated in the study, but the authors acknowledge the support of the national cycling charity CTC, British Cycling, Sky Ride and Cycling Weekly magazine. They state the funders had no role in the study other than providing funding.

The study was published in the peer-reviewed Journal of Men's Health on an open access basis, so it is free to read online.

The story was picked up by both the Mail Online and The Daily Telegraph, with each choosing to report the findings differently.

The Mail was keen to emphasise the link to prostate cancer, as seen in the inaccurate headline stating that, "Men who cycle more than nine hours a week are six times more likely to develop prostate cancer". The rest of the coverage of the study is appropriate and goes on to report that no causal relationship has been proven. 

The Telegraph took a more cheerful approach, emphasising that the study found no link between frequent cycling and infertility or erectile dysfunction. Its reporting was also balanced and accurate.

 

What kind of research was this?

This was a cross-sectional study looking at associations between erectile dysfunction, infertility and prostate cancer in a group of regular male cyclists from the UK. 

A cross-sectional type of study looks at the characteristics of a population at a given point in time. This type of study is useful for finding out how common a particular condition is in a population. Often, the relationships between the characteristics or factors assessed are then analysed.

Importantly, because this study only looks at one point in time, it cannot establish cause and effect between factors, as it does not show which factor came first.

 

What did the research involve?

The research included 5,282 male cyclists from the Cycling for Health UK Study. This study aimed to examine cycling habits and the health of men from a variety of cycling backgrounds, ranging from commuters to amateur racing cyclists.

In the current study, an online survey was advertised from October 2012 to July 2013 through cycling magazines and UK cycling bodies. The survey included questions on:

  • demographics – age, sex and education
  • cycling history – number of years cycling, average weekly total and commuting cycling distances, as well as time, speed and best times for various standard distance competitive cycling races
  • body measurements – weight, height and resting heart rate, which was self-recorded from the wrist

The survey also captured additional information on:

  • alcohol intake
  • current and past cigarette use
  • history of cardiovascular events, such as stroke or heart attack
  • any cancers
  • diagnosis or treatment of hypertension (high blood pressure), high cholesterol or diabetes
  • participation in non-cycling physical activity

The men were then asked whether they had experienced erectile dysfunction in the past five years and if they had been diagnosed with infertility or prostate cancer by a doctor.

The researchers used statistical techniques to determine the association between the number of hours a week spent cycling and erectile dysfunction, infertility or prostate cancer.

They did this by categorising the amount of time a week spent cycling into four groups:

  • fewer than 3.75 hours per week
  • between 3.76 hours and 5.75 hours per week
  • between 5.76 and 8.5 hours per week
  • more than 8.5 hours per week

The researchers only analysed the data of men aged over 50 (2,027 men) because prostate cancer diagnosed under the age of 50 accounts for less than 1% of diagnoses.

They then adjusted the results for potential confounders, including:

  • age
  • smoking status
  • weekly alcohol intake
  • body mass index (BMI)
  • diagnosed hypertension (high blood pressure)
  • other physical activity

 

What were the basic results?

The average age of the men was 48.2 (range 16 to 88 years), the average BMI was 25.3 kg, and 3.8% of the cyclists were current smokers. On average, they cycled 4.2 days a week for 6.5 hours a week.

Of the 5,282 men, 8.4% (444 men) self-reported erectile dysfunction in the past five years, 1.2% (63 men) reported a diagnosis of infertility, and 0.8% (42 men) reported a diagnosis of prostate cancer. Prostate cancer was reported in 1.8% of men aged over 50 (figure not reported).

The main results of this study were:

  • there was no association found between cycling time and erectile dysfunction
  • there was no linear association found between cycling time and infertility – in fact, cycling for between 3.76 and 5.75 hours per week was actually associated with a decreased risk of infertility (odds ratio [OR] 0.44, 95% confidence interval [CI] 0.21 to 0.94)
  • after adjusting for confounders, a graded increase in the association between cycling time and the risk of prostate cancer in men aged over 50 was found – the risk increased as the hours a week spent cycling increased

Compared with cycling less than 3.75 hours a week:

  • cycling between 3.76 and 5.75 hours had an OR for prostate cancer of 2.94
  • cycling between 5.76 and 8.5 hours had an OR of 2.89 
  • cycling for more than 8.5 hours had an OR of 6.14

To determine if the results for prostate cancer were related to health-seeking behaviour (the idea that more active people are more likely to be aware of their health and seek treatment if necessary), associations between the time spent cycling and yearly consultations with doctors were also analysed. No association was found.

 

How did the researchers interpret the results?

The researchers concluded weekly cycling duration was not associated with erectile dysfunction or infertility. They also conclude there is a dose-response association between cycling time and prostate cancer in men aged over 50, particularly for men who cycle more than 8.5 hours a week.

One of the researchers, Dr Mark Hamer from University College London, is reported in the media as saying: "These results are not straightforward. It may be that these men are more health aware and therefore more likely to get a diagnosis."

Those who are cycling the most did not make up a huge sample, so more research is needed. Hamer went on to say that, "We are talking about very keen cyclists who are on their bikes for nine hours a week – not people who are just commuting to work."

He also made the point that cycling leads to health benefits in other areas, such as reducing the risk of type 2 diabetes, heart disease and stroke.

 

Conclusion

This study has looked at the associations between the number of hours spent cycling a week and erectile dysfunction, infertility and prostate cancer in men over the age of 50 who cycle regularly.

It found no association between the time spent cycling and erectile dysfunction or infertility, but did find a dose-response association with prostate cancer for men over the age of 50, with risk increasing as the time a week spent cycling increased.

As the researchers point out, this type of study cannot prove causality (that increased cycling time leads to prostate cancer), only an association. Different study designs, such as randomised controlled trials, are required before we can draw these kinds of conclusions.

There are several other limitations of this study worth noting:

  • The survey was only sent to current cyclists. There was therefore no control group to compare the results with, and the results would have missed men who no longer cycle because of ill health.
  • The study was carried out at only one point in time, so self-reported cycling may have differed if the men were surveyed at a different point in time. Factors such as the time of year when they answered the survey (whether it was winter or summer) may have affected their responses.
  • Only self-reported data was required for classifying men as having erectile dysfunction in the past five years. It is possible that either men who reported having erectile dysfunction in fact didn't have this, or that some men with the condition were potentially missed. The researchers note the prevalence of erectile dysfunction was lower in this study than in previous studies. But they also acknowledge that because the survey was anonymous and online, this may have reduced any embarrassment of reporting erectile dysfunction and infertility.
  • Only self-reported data was used to categorise the number of hours a week spent cycling. It is possible men either over or underestimated the amount of cycling they do a week.
  • The study was internet-based, so there was no opportunity for interviews or physical examination, which limited the ability to explore the reported diagnoses further.
  • Overall, there were only about 42 men out of 5,282 in the study who had prostate cancer, and fewer than 42 cases among the men aged over 50 (figure not reported). This means analyses were only performed on a relatively small sample of men.

Cyclists need not panic, as this research has not proved a cause and effect relationship between prostate cancer and the amount of time a week a man spends cycling.

In fact, cycling regularly has many health benefits, including a reduced risk of diabetes, high blood pressure, heart attack, stroke and cancer.

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter. Join the Healthy Evidence forum.

Links To The Headlines

Men who cycle more than nine hours a week are six times more likely to develop prostate cancer, study finds. Mail Online, July 8 2014

Cycling does not cause infertility, British scientists find. The Daily Telegraph, July 7 2014

Links To Science

Hollingworth M, Harper A, Hamer M. An Observational Study of Erectile Dysfunction, Infertility, and Prostate Cancer in Regular Cyclists: Cycling for Health UK Study. Journal of Men's Health. Published online June 11 2014

Categories: Medical News

Gene mutation linked to distinct type of autism

Medical News - Tue, 07/08/2014 - 14:26

“Have scientists found the autism gene?" asks the Mail Online.

The news is based on a genetic study that found children with autism spectrum disorder (ASD) were more likely to have a mutation in a gene called CHD8 than children without the disorder.

ASD is an umbrella term for conditions affecting social interaction, communication, interests and behaviour.

However, talk of a single autism gene is premature. This is relatively early stage research. The genetic test will need to be further tested and validated in large and diverse groups to ensure it accurately identifies people with ASD.

The results linking the CHD8 mutation to a specific sub-type of ASD with a similar set of symptoms also made the news but was based on just 15 people. This means this sub-analysis cannot be viewed as reliable.

The hope is that if a test does reliably predict what set of symptoms a child with ASD is likely to develop, an individual treatment and care plan can be devised to meet their future needs.

 

Where did the story come from?

The study was carried out by a large international collaboration of researchers from medical and academic institutions and was funded by a variety of non-commercial institutions including Simons Foundation Autism Research Initiative, the National Institutes for Health (US) and the European Commission.

The study was published in the peer-reviewed science journal Cell.

As with many Mail Online health stories the headline was misleading. There is no such thing as a single autism gene, in the same way that there is no such thing a single type of autistic disorder.

The actual reporting of the study in the main body of the story was accurate and informative. (Mail Online journalists may want to have a quiet word with their headline writers).

 

What kind of research was this?

This was a genetic study looking for gene variants associated with autism spectrum disorder.

Autism spectrum disorder (ASD) is an umbrella term for a number of conditions that affect social interaction, communication, interests and behaviour. Symptoms can range from mild to severe.

In some cases ASD can lead to below average intelligence and learning difficulties. In other cases intelligence is unaffected or above average.

The researchers describe how different subtypes of ASD have been described based on behaviour but with limited success because behaviour varies so much within and between subtypes. As opposed to behaviour, the researchers thought genes may hold the key to the different subtypes of ASD and sought to investigate this hypothesis.

 

What did the research involve?

Researchers sequenced the DNA of 3,730 children with development delay or ASD looking for variations in a gene called CHD8 – a gene previously associated with ASD. They looked to see if any genetic variations were associated with being diagnosed with ASD overall, but also for any links to specific characteristics of subsets of people with ASD such as distinct faces, a larger than average head (marcoencephaly), and stomach or digestive complaints.

While the genetic study recruited a lot of children, the assessment of specific characteristics was based on just 15 people.

This sort of genetic study is often used to further scientific understanding of any genetic origins of a disease. Scientists know what many genes do, so if there is a genetic link it helps them understand the biology of the disease process, this can ultimately lead to ideas for new drugs and treatments.

 

What were the basic results?

The genetic analysis revealed 15 different and independent genetic variations (mutations) in the CHD8 gene in the children with development delay or ASD.

Thirteen of the 15 CHD8 mutations associated with ASD caused the resulting CHD8 protein to shorten (truncate). These truncating mutations were not found in 8,792 healthy controls – including 2,289 unaffected siblings – suggesting the mutations were relatively specific to the disease.

The presence of one of the genetic mutations identified was linked to an increased likelihood of an ASD diagnosis overall. 

Specific CHD8 mutations were also associated with distinct characteristics, but only using 15 people with ASD so should be taken with a pinch of salt. These were:

  • increased head size accompanied by rapid early postnatal growth
  • a facial phenotype marked by prominent forehead
  • wide-set eyes
  • pointed chin
  • increased rates of digestive complaints
  • sleep dysfunction

As a follow-up study, the researchers disrupted the CHD8 gene in zebra fish – a popular research animal for genetic manipulation as they breed very quickly and adapt well to being housed in aquariums. They found the effects of this were broadly similar to ASD type symptoms in humans including larger head size as results of expansion of the forebrain and midbrain, and impairment of gastrointestinal motility.

 

How did the researchers interpret the results?

The researchers concluded their findings “suggest that CHD8 disruptions represent a specific pathway in the development of ASD and define a distinct ASD subtype”.

 

Conclusion

This study used many thousands of children to identified mutations in the CHD8 gene that were associated with the development of ASD. Much less convincing was the finding that CHD8 mutations might be associated with distinct characteristics within the spectrum of disease, potentially representing a genetically defined subtype, as this was based on just 15 people.

Identifying subtypes of ASD is important to guide diagnosis, prognosis and disease management to maximise quality of life. This study is interesting because most categorisation of ASD has focused on behavioural dimensions. By contrast, this study flipped this on its head and looked at the genetic dimension of the disease, which revealed some statistically significant links.

Knowing this gene-disease link will help researchers understand the biological origins of the disease, which improves the chance of treatments being discovered or better ways to manage symptoms of the conditions to improve quality of life.

This is relatively early stage research; the genetic test will need to be further tested and validated in large and diverse groups to ensure it accurately identifies people with ASD and or any subtypes.

Today this test does not help people with ASD, but it does help pave the way for potential improvements in the future.

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter. Join the Healthy Evidence forum.

Links To The Headlines

Have scientists found the autism GENE? Breakthrough as specific link between DNA and the condition is discovered. Mail Online, July 7 2014

Links To Science

Bernier R, Golzio C, Xiong B, et al. Disruptive CHD8 Mutations Define a Subtype of Autism Early in Development. Cell. Published online July 6 2014

Categories: Medical News

New Alzheimer’s test may help future clinical trials

Medical News - Tue, 07/08/2014 - 14:25

“Research in more than 1,000 people has identified a set of proteins in the blood which can predict the start of the dementia with 87% accuracy,” BBC News reports.

The primary goal of the test was to predict whether people with mild cognitive impairments (usually age-related memory problems) would go on to develop “full-blown” Alzheimer’s disease over approximately a year.

There is currently no cure for Alzheimer’s, so people may question whether an early warning system for the disease is of any practical use.

However, having a relatively reliable method of identifying high-risk people who will develop Alzheimer’s could be useful in recruiting suitable candidates for clinical trials investigating future treatments.

An important point is that, while the test accuracy rate of 87% sounds impressive, this may not be a good indicator of how useful the test would be if it was used in the wider population.

Given real world assumptions on the proportion of people who have mild cognitive impairment that progress to Alzheimer’s disease (10-15%), the predictive ability of a positive test falls to around 50%. This means that those who have a positive test have a 50:50 chance of going on to have Alzheimer's.

Consequently, on its own, this test is unlikely to be much good for use in clinical practice for the general population. However, refining this test and combining it with other methods (such as a lipid test we discussed in March) might improve accuracy rates, making it a viable predictive tool in the future.

 

Where did the story come from?

The study was led by researchers from Kings College London and was funded by the Medical Research Council, Alzheimer’s Research, The National Institute for Health Research (NIHR) Biomedical Research Centre and various European Union (EU) grants.

Some of the researchers reported potential conflicts of interest, as they had patents filed with, or work for, Proteome Sciences plc. Proteome Sciences is a life sciences company with a commercial interest in biomarking testing. Another researcher works for the pharmaceutical company GlaxoSmithKline (GSK). No other conflicts of interest were reported.

The study was published in the peer-reviewed medical journal Alzheimer’s & Dementia. The study is open-access, so is free to read online.

The media coverage was broadly accurate, but none reported the positive predictive value of the test. This reduces the impressive-sounding 87% accurate figure to a predictive value of a positive test to around the 50% level, depending on the the rate of conversion from mild cognitive impairment to Alzheimer's disease.

This important information should have been highlighted to avoid overstating the utility of the test on its own.

 

What kind of research was this?

This study used information from three existing cohorts of people, to study the prognostic value of a new blood test in predicting people’s progress from mild cognitive impairment to Alzheimer’s disease. 

There are currently no drug treatments that cure Alzheimer's, although there are some that can improve symptoms or temporarily slow down progression of the disease in some people.

Some believe that many new clinical trials fail because drugs are given too late in the disease process.

A blood test could be used to identify patients in the early stages of memory loss, who could then be used in clinical trials to find drugs to halt the disease's progression.

 

What did the research involve?

The researchers studied the blood plasma of 1148 elderly people – 476 with clinically diagnoses of Alzheimer’s disease, 220 with mild cognitive impairment (a mild form of dementia) and 452 with no signs of dementia. They then studied how differences in proteins correlated with disease progression and severity over a period of between one and three years.

Diagnosis of Alzheimer’s disease was made using established criteria, but three groups were used and combined, so the diagnosis tool used in each was actually different.

Other standardised clinical assessment included the Mini-Mental State Examination (MMSE) for measuring general cognition and cognitive decline, as well as the Clinical Dementia Rating (ANM and KHP-DCR only) for measuring dementia severity.

Participants’ brains were also scanned using an MRI scanner, to measure the volume and thickness of the brain to look for further signs of Alzheimer’s or brain deterioration.

The researchers started with 26 candidate proteins they thought might be useful to predict progression and severity. These were tested in different combinations and reduced to the best 10, based on specificity and sensitivity of the test.

 

What were the basic results?

The team identified 16 proteins in participants’ blood that correlated with disease severity and cognitive decline.

The strongest associations predicting progression from mild cognitive impairment to Alzheimer’s disease were formed of a panel of 10 proteins. Depending on different threshold inputs, this test had an accuracy of between 72.7% and 87.2%, and a positive predictive value of between 47.8% and 57.1%.

The predictive value of a test is the proportion of positive and negative results that are true positive and true negative results. That is an indication of each result's ability to correctly identify people with a specific condition, and not misdiagnose people who don’t have the condition.

The accuracy of the protein test was improved when it was combined with a test for gene variant associated with increased amyloid protein in the brain (APOE ε4 allele).

This combined test predicted progression from mild cognitive impairment to Alzheimer’s disease over a year, with an accuracy of 87% (sensitivity 85%, and specificity 88% and PPV 68.8%). The PPV was based on the 24% of people with mild cognitive impairment who went on to develop Alzheimer’s disease in the study. However, there are a wide range of estimates for this conversion, many of which are much lower.

For example, figures from the Alzheimer’s society estimate that between 10% and 15% of people with mild cognitive impairment progress to Alzheimer’s disease each year. Based on this assumption, the test has a positive predictive value of between 44% and 56%. This means that a positive result on the combined test will only identify people correctly in around half of cases, and potentially less.

The average time for mild cognitive impairment to develop into Alzheimer’s in the study was around one year.

 

How did the researchers interpret the results?

The study authors concluded they had, “identified 10 plasma proteins strongly associated with disease severity and disease progression” and that, “such markers may be useful for patient selection for clinical trials and assessment of patients with predisease subjective memory complaints”.

 

Conclusion

This research developed and tested a new blood test that predicted the progression from mild cognitive impairment to Alzheimer’s disease, with an accuracy of 87% approximately a year before development.

However, in a non-experimental setting, the test may be much less effective than the 87% figure suggests. Based on figures from the Alzheimer’s society indicating that 10-15% of people or less progress each year, a positive result on the test would only be expected to be correct around 50% of the time.

The test is unlikely to be used by itself, so its predictive ability may be improved if used in combination with other tests in development. The predictive ability of the test would improve if the 10-15% assumptions turned out to be an underestimate, and reduce if the conversion assumption was an overestimate.

A further limitation to the test, if it was to be used for general screening, is that it only made predictions a year in advance of Alzheimer’s diagnosis. This is certainly better than nothing, but Alzheimer’s disease is often diagnosed at a later stage, with the disease having already caused damage for many years (the exact time is variable). A test that predicted Alzheimer’s disease using a 5 or 10-year period would be a much bigger advancement.

As there is currently no cure for Alzheimer’s, there is likely to be a debate about whether patients would want to know this information if the test was successfully developed further and made available in mainstream medicine.

Some people may prefer to know their prognosis, as it may influence what they do or the way they live.

Others may prefer not to know, given that current drug treatments can only slow the progression of the disease in some people, and do not improve the symptoms in all of those affected.

However, as the researchers point out, the test has an important potential use. If confirmed to be effective in further studies, the test could be used to recruit people into clinical trials, testing new drugs or treatments to help future generations.

Promising Alzheimer’s drugs are reported to have a high failure rate in human clinical trials.

Many researchers believe this to be because by the time a person is diagnosed with Alzheimer’s, it is too late to do anything about it, with medicine unable to reverse the brain damage that has already been caused.

Therefore, scientists are looking for ways to intervene earlier.

Knowing who will likely develop Alzheimer’s in a year is a step forward in this effort, as researchers can test different drugs and treatments, and would be able to see if they are preventing the progression from mild cognitive decline to Alzheimer’s disease. This isn’t currently possible with existing diagnostic tools and approaches.

One of the limitations of this research is that it did not use post-mortem assessments to diagnose Alzheimer’s and assess its severity. Instead, it relied on clinical diagnosis, severity scores and MRI scans. While these are practical and valid measures, the gold standard for Alzheimer’s diagnosis is a post-mortem examination of the brain. This could be corroborated with the test results in future studies.

This is the first research group to test the predictive ability of this specific panel of proteins.

Interestingly, a previous small study found 10 other blood lipid biomarkers predicted, with 90% accuracy, 28 cognitively normal participants who progressed to have either mild cognitive impairment or mild Alzheimer’s disease within two to three years, compared to those who did not.

It will be important for future research groups to confirm and replicate the findings, to see if the results are the same, or if a combination of these approaches improves the predictive values in larger trials.

Analysis by Bazian. Edited by NHS ChoicesFollow Behind the Headlines on TwitterJoin the Healthy Evidence forum.

Links To The Headlines

Alzheimer's research in 'major step' towards blood test. BBC News, July 8 2014

Alzheimer's disease could be prevented after new blood test breakthrough. The Daily Telegraph, July 8 2014

Blood test breakthrough in search for Alzheimer's cure. The Guardian, July 8 2014

New blood test 'paves way to halt dementia': Patients could get drugs earlier. Daily Mail, July 8 2014

Alzheimer's blood test 'could be available in two years'. ITV News, July 8 2014

Alzheimer’s blood test could predict whether disease will develop within a year. Daily Mirror, July 8 2014

Blood test to give early warning of Alzheimer’s. The Times, July 8 2014

Alzheimer's breakthrough: Simple new test will help millions beat cruel disease. Daily Express, July 8 2014

Links To Science

Hye A, Riddoch-Contreras J, Baird AL, et al. Plasma proteins predict conversion to dementia from prodromal disease. Alzheimer’s & Dementia. Published online July 8 2014

Categories: Medical News

Two-question test for alcohol misuse 'effective'

Medical News - Mon, 07/07/2014 - 15:00

“Do you regularly have more than six drinks in one sitting? Or do you regret a drunken escapade that took place in the past year? Answering yes to both questions may be a sign that you have a drink problem," the Mail Online reports.

This comes following a systematic review, which is, essentially, a study of studies.

The review aimed to examine whether short and quick screening approaches (comprising just one or two questions) can successfully and accurately identify people with alcohol problems during a GP visit.

The prevalence of people attending an appointment who have some form of alcohol problem has been suggested to be as high as 30%.

From the seven papers identified, using a single screening question such as “How often do you have six or more drinks on one occasion?” or “As a result of your drinking or drug use, did anything happen in the last year that you wish didn’t happen?” was not very accurate.

However, asking two screening questions increased accuracy (sensitivity) to 87.2%, meaning that only around one person in seven would be missed.

Asking either one or two questions would not be recommended as a single approach, however, because they’re not accurate enough. Instead, they appear to serve well as an initial screening technique, if they are then followed by a standard screening questionnaire.

 

Where did the story come from?

The study was carried out by researchers from Leicester General Hospital, and received no sources of financial support.

The study was published in the peer-reviewed medical journal British Journal of General Practice.

The Mail Online’s reporting of the study is accurate, but didn’t make clear that the initial two-question screening was not proposed to be used by itself.

This initial screening would be followed up by one or more longer, validated alcohol screening questionnaires if an alcohol problem was initially suspected.

Describing this more measured approach may have been less newsworthy than warning people that their GP was going to make the decision based on just two questions.

 

What kind of research was this?

This was a systematic review that aimed to see whether asking one or two simple questions could be an accurate and acceptable method for general practice screening to find out if people have an alcohol problem.

Previous research, the study authors’ said, suggested that up to a third of people attending general practice may be drinking at a level harmful to their health (called at-risk drinking) or have an alcohol use disorder. Many researchers consider that GPs might be well placed to identify any drink-related problems, as they can offer help and support at an early stage.

This study aimed to review the global literature to see if there was any evidence to support the use of very short alcohol screening questions in general practice.

 

What did the research involve?

The authors searched three literature databases – MEDLINE, PubMed and Embase – up to January 2014, using various search terms, including different terms for alcohol use disorders and terms to identify screening questions. They looked at the identified studies and only included those that assessed one or two questions to identify alcohol problems. They appraised the quality of included studies, and extracted information including study setting, patient characteristics, sample size, questions used to identify alcohol problems and accuracy of the screening questions.

 

What were the basic results?

The researchers identified six publications investigating one-question screening, and two studies investigating two-question screening. All were diagnostic studies designed to investigate the accuracy of diagnosing alcohol problems. The sample size of individual studies ranged from 227 to 1333 participants.

Most studies used valid diagnostic criteria to identify alcohol use disorders, and the overall prevalence of disorders across studies was 21%.

A single-question approach helped identify 453 out of 800 individuals with an alcohol use problem, with a pooled sensitivity across studies of 56.6%. This means that 56.6% of people with an alcohol problem were correctly identified by the screening question as having a problem.

On the flip side, 43% of people with an alcohol problem would have incorrectly been given the all-clear (false negatives).

By comparison, the pooled specificity of the single question was 81.3%, meaning that 81.3% of people without an alcohol problem were correctly identified by the screening question as not having an alcohol problem suggested (18.7% false positive rate). However, the individual studies had quite variable sensitivity and specificity results.

The most accurate single questions appeared to be “How often do you have six or more drinks on one occasion?” and “As a result of your drinking or drug use, did anything happen in the last year that you wish didn’t happen?” Both were reported to have excellent performance for ruling out people with alcohol problems, with low false negative results.

For the two-question approach, the sensitivity was 87.2% (proportion accurately identified to have an alcohol problem), and the specificity was 79.8% (proportion accurately identified as not having an alcohol problem). The optimal combination of questions was “recurrent drinking in situations in which it is physically hazardous” combined with “drinking in larger amounts or over a longer period than intended”.

The currently used 10-item AUDIT alcohol use questionnaire was found to be the most accurate single method for identifying alcohol use disorders, followed by the 4-item CAGE questionnaire.

However, the difficulty with these methods is that they would take GPs much longer to use these as screening methods. They were followed in accuracy by asking two screening questions, followed by one question. 

The most accurate method was considered to be a stepwise approach of asking two initial screening questions, followed by the AUDIT or CAGE questionnaires to confirm.

 

How did the researchers interpret the results?

The researchers conclude that “two brief questions can be used as an initial screen for alcohol problems, but only when combined with a second-step screen. A brief alcohol intervention should be considered in those individuals who answer positively on both steps”.

 

Conclusion

This systematic review has examined global literature to identify studies that have assessed using one or two screening questions in general practice to identify people with alcohol use problems. The pooled results across the seven publications found the prevalence of alcohol use problems to be 21%.

Using a single question such as “How often do you have six or more drinks on one occasion?” or “As a result of your drinking or drug use, did anything happen in the last year that you wish didn’t happen?” was not very accurate, having a sensitivity of just over half. This means that half the people with alcohol problems would be missed. However, asking two screening questions increased sensitivity to 87.2%, meaning that less than 13% would be missed.

The optimal two question categories were “recurrent drinking in situations in which it is physically hazardous”, combined with “drinking in larger amounts or over a longer period than intended”.

However, as the researchers highlight, asking either one or two questions would not be recommended as a single approach, because they’re not accurate enough. They would need to be followed by the longer 10-item AUDIT alcohol use questionnaire or the 4-item CAGE questionnaire in a stepwise approach.

Both of these questionnaires used alone are more accurate than either one or two questions used alone, but would take GPs much longer to use these as screening methods. However, asking an initial two questions followed by AUDIT or CAGE would be the best way to identify people with alcohol problems, hopefully targeting them towards interventions.

However, as the study says, there are limitations. Despite the systematic review design, only seven diagnostic studies were identified, and it was not possible to conduct subgroup analyses. For example, it can’t tell us whether accuracy differs by male or female sex, or how good the screening methods would be at identifying people with different types of alcohol problem (e.g. people with actual alcohol dependence, or just harmful or hazardous drinking habits).

The researchers say that in the UK, “experts have recommended routine alcohol screening focusing on new patient registrations, general health checks and special types of consultation”. However, as they say, there are many things to consider, including the acceptability of asking even a single question related to alcohol use, “as some questions may not be welcome in unselected primary care attendees”.

The researchers aptly put forward “a cautious recommendation for one or two verbal questions as a screening test for alcohol-use disorder in primary care, but only when paired with a longer screening tool to decide who warrants a brief alcohol intervention”.

Further research is needed to clarify the added value of this approach compared with clinical assessment without the use of screening questions.

Despite alcohol misuse being associated with psychological denial, most people with an alcohol problem know that they have a problem.

A good source of advice is your GP. Be honest with them about how much you drink.

If your body has become dependent on alcohol, stopping drinking overnight can cause severe withdrawal symptoms, and in some cases can even can be life-threatening, so get advice about cutting down gradually.

Your GP may refer you to a local community alcohol service. Ask about free local support groups, day-centre counselling and one-to-one counselling.

Read more about how to seek help for alcohol misuse.  

Analysis by Bazian. Edited by NHS Choices
Follow Behind the Headlines on TwitterJoin the Healthy Evidence forum.

Links To The Headlines

Do you consume more than six drinks in one sitting at least once a month? And do you regret a drunken incident in the past year? Two questions that tell your GP you have a drink problem. Mail Online, July 7 2014

Links To Science

Mitchell AJ, Bird V, Rizzo M, et al. Accuracy of one or two simple questions to identify alcohol-use disorder in primary care: a meta-analysis. British Journal of General Practice. Published online July 1 2014

Categories: Medical News

Aggressive breast cancer protein discovered

Medical News - Mon, 07/07/2014 - 14:30

"A breakthrough by scientists could lead to a new treatment for one of the most aggressive forms of breast cancer," the Mail Online reports. Researchers have identified a protein called integrin αvβ6, which may help trigger the spread of some types of breast cancer.

Up to a third of breast cancers are HER2-positive cancers. These are cases of breast cancer where growth is driven by a protein called human epidermal growth factor receptor 2 (HER2). These types of cancer can be particularly aggressive.

Seventy percent of people with HER2-positive breast cancers develop resistance to Herceptin, the main drug treatment for these cancers, effectively leaving them with no treatment options.

This laboratory study examined samples of breast cancer tissue from two cohorts of women with breast cancer. Researchers looked at the expression of a protein called integrin αvβ6, which has been shown to interact with HER2 to stimulate cancer growth.

The researchers found women who had higher expression of integrin αvβ6 in their breast cancer tissue had poorer five-year survival rates, particularly when they were also HER2 positive.

The researchers then studied mice that had been grafted with breast cancer tissue. But a potential new treatment called 264RAD was found to block integrin αvβ6 in the rodents.

Giving this treatment in combination with Herceptin stopped cancer growth, even in breast cancer tissues resistant to Herceptin.

Clinical trials of 264RAD in women with this particularly high-risk type of breast cancer are now required.

 

Where did the story come from?

The study was carried out by researchers from Barts Cancer Institute, Queen Mary, University of London, and was funded by the Breast Cancer Campaign and the Medical Research Council.

It was published in the peer-reviewed Journal of the National Cancer Institute, and is open access and available to read for free online.

Both the Mail Online and The Daily Telegraph's reporting of the study is accurate and informative.

 

What kind of research was this?

This was a laboratory study examining samples of breast cancer tissue from two cohorts of women with breast cancer. Researchers looked for the expression of a particular protein called integrin subunit beta6 (integrin αvβ6). They then looked at how the expression of this protein was associated with cancer survival.

The researchers explain that in up to a third of all breast cancers, a particular protein called human epidermal growth factor receptor 2 (HER2) is overexpressed. This is associated with a very aggressive breast cancer.

These cancers are aggressive because HER2 triggers signalling pathways that stimulate breast cancer cells to grow out of control. This means the cancer cells are more likely to spread into the lymph nodes or to other major organs of the body (known as metastases or metastatic cancer).

Currently, some HER2-positive breast cancers can be treated using the biological antibody treatment Herceptin (trastuzumab). Herceptin works by binding to the protein receptors and blocking them so HER2 cannot stimulate the growth of the breast cancer cells.

However, as the researchers point out, more than 70% of people have developed resistance to Herceptin, leaving them without other treatment options. New treatments are therefore needed for people with HER2-positive breast cancers.

A molecule called TGFβ has been shown to promote HER2-driven cancer by increasing the migration, invasion and spread of breast cancer cells. Integrin αvβ6 has been identified as an activator of TGFβ and implicated in promoting the growth of various types of cancer.

With this knowledge, this research aimed to see whether integrin αvβ6 could influence HER2-positive breast cancer and if inhibiting its action helped reduce the cancer size and spread.

 

What did the research involve?

The research included two cohorts of people with breast cancer:

  • a Nottingham cohort that included 1,795 consecutive women treated from 1986 to 1998
  • a London cohort that included 1,197 women mostly treated from 1975 to 1998

The researchers were able to gather complete information on the women's tumour types, including whether they were HER2 positive.

They examined tissue samples for the expression of integrin αvβ6 and looked at how this was associated with survival by seeing whether the women were still alive at five-year follow-up checks.

The researchers also looked at survival rates when there was co-expression of both HER2 and integrin αvβ6.

Further laboratory experiments using mice grafted with breast cancer tissue examined treatment options using Herceptin (trastuzumab), the antibody known to block HER2, and an antibody called 264RAD, which was found to block integrin αvβ6.

 

What were the basic results?

High expression of integrin αvβ6 was found in 15-16% of breast cancer tissue samples from the two cohorts of women.

The researchers found a significant association between the expression of integrin αvβ6 and survival.

In women with a high expression of integrin αvβ6, five-year survival dropped from 75.6% to 58.8% in the London cohort, and from 84.1% to 75.0% in the Nottingham cohort.

In statistical terms, this meant that high expression was associated with an almost doubled risk of mortality.

Even with adjustment for tumour stage, size and grade, integrin αvβ6 was an independent predictor of overall survival.

For the Nottingham cohort, the researchers also had data available on distant spread (metastases) – 39.5% of those who were integrin αvβ6-positive had metastases, compared with 30.9% who were integrin αvβ6 negative.

When looking at co-expression of both integrin αvβ6 and HER2, they found this combination was associated with a particularly poor prognosis. In women who were HER2 positive, five-year survival was 65.1%, but it dropped to 52.8% if integrin αvβ6 was also strongly expressed.

The studies in mice grafted with human tumour tissue found both Herceptin and the study molecule 264RAD individually slowed tumour growth, but the combination of the two effectively stopped tumour growth, even in breast cancer tissues resistant to Herceptin.

 

How did the researchers interpret the results?

The researchers conclude that the overexpression of integrin αvβ6 in breast cancer is a poor prognostic factor associated with lower survival and the development of distant metastases.

They say the overexpression of both integrin αvβ6 and HER2 is associated with an even poorer prognosis.

The researchers feel the likely biological explanation is integrin αvβ6 and HER2 co-operate within the same molecular complex and integrin αvβ6 mediates the invasive behaviour of HER2-positive cancer.

They suggest targeting αvβ6 using the antibody 264RAD, either alone or in combination with Herceptin, may provide a novel therapy for people with this very high-risk breast cancer sub-type (HER2/αvβ6 positive), particularly if it is resistant to Herceptin.

 

Conclusion

This is a valuable laboratory study that furthers our understanding of the way HER2 may promote the growth, proliferation and spread of breast cancer cells, possibly through the influence of the protein integrin αvβ6.

The researchers suggest up to 40% of people with HER2-positive breast cancers may also have a high expression of integrin αvβ6.

The discovery that integrin αvβ6 may play a role in mediating the growth and progression of these cancers hopefully opens up new treatment possibilities for people with HER2-positive cancers.

As the researchers suggest, their study supports the proposal that testing breast tissue biopsies for the expression of αvβ6 should become a routine procedure to stratify women with breast cancer into this new very high-risk αvβ6-positive/HER2-positive group.

The laboratory experiments in mice with human breast cancer tissue grafts suggested the combination of Herceptin with the antibody 264RAD could be effective in stopping tumour growth in this group.

However, the development of the 264RAD treatment is still in the very early stages. Clinical trials in people with αvβ6-positive and HER2-positive breast cancer are now awaited. These will tell us whether 264RAD – either alone or in combination with Herceptin – could be an effective treatment option for this very high-risk sub-group.

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter. Join the Healthy Evidence forum.

Links To The Headlines

New treatment to stop spread of breast cancer: Scientists pinpoint molecule that causes cells to spread quickly. Mail Online, July 4 2014

Breast cancer breakthrough brings hope. The Daily Telegraph, July 4 2014

Links To Science

Moore KM, Thomas GJ, Duffy SW, et al. Therapeutic Targeting of Integrin αvβ6 in Breast Cancer. Journal of the National Cancer Institute. Published online June 30 2014

Categories: Medical News

Children’s TV contains unhealthy 'food cues'

Medical News - Fri, 07/04/2014 - 15:00

“Children are being bombarded with scenes of unhealthy eating on TV,” The Independent reports. Researchers looking at public broadcasting in the UK and Ireland have found that children’s TV contains a high number of visual and verbal references to unhealthy foods.

In the UK, direct TV advertising of unhealthy food to children has been banned since 2008.

However, the researchers were still interested in whether children’s TV broadcast by state-funded organisations still promotes unhealthy food choices to young children.

Researchers assessed five weekdays of children programmes from the BBC and its Irish equivalent, RTE. They were interested in what they describe as “cues” – visual, verbal and plot-driven references to specific foods and drinks.

Unhealthy foods accounted for just under a half of specified food cues, and sugar-sweetened beverages for a quarter. The context of the food and drink cue was mostly positive or neutral, with celebratory/social motivations the most common.

As the programmes were on non-commercial TV, it could be the case that the inclusion of said cues was due to cultural, and not commercial, reasons.

The plot device of a “slap-up meal” as a reward for a job well done, or as a treat, is a constant in children’s fiction, ranging from Rastamouse to the Famous Five.

Importantly, however, the study can’t tell us whether the food and drink cues directly influence the children’s food and drink requests or their eating patterns.

 

Where did the story come from?

The study was carried out by researchers from the University of Limerick in Ireland and Dalhousie University, in Halifax, Canada. No sources of financial support are reported. 

The study was published in the peer-reviewed medical journal Archives of Diseases of Childhood, and has been released on an open-access basis, so is free to read online.

Overall reporting of the study by BBC News and The Independent is of a good quality.

The BBC includes useful wider debate on the issue, with Malcolm Clark, coordinator of the Children's Food Campaign, saying: “It is disappointing that children’s TV seems to be so tamely reflecting the obesogenic environment we all live in, rather than presenting a more positive vision of healthy, sustainable food.”

An obesogenic environment is an environment that promotes unhealthy food choices, such as a workplace located next to lots of fast food outlets. We discussed obesogenic environments back in March of this year.

A BBC spokesperson defended its content, saying: “We broadcast lots of programmes to promote healthy eating to children and to help them understand where food comes from, with series like I Can Cook, Incredible Edibles and Blue Peter.”

 

What kind of research was this?

This was an observational study that examined the frequency and type of food and drink references contained on children’s TV programmes during five weekday mornings, comparing UK and Irish state-funded television channels.

Previous research has demonstrated how there is an association between child weight and the amount of TV that they watch.

The researchers suggest that this could be due to a combination of greater periods of inactivity, and exposure to food advertising while watching TV.

Advertisements targeted at children are said to be dominated by high-calorie, low nutritional-quality foods, and previous research has associated child TV viewing with consumption of low nutrient-density foods, persuading parents to purchase such food, which leads to the development of poor eating habits.

Direct advertising to children of “junk food” has been banned during children’s programming in the UK since 2008, although many children watch adult programming, such as talent shows and soap operas.

There is also the possibility that non-commercial programming may promote unhealthy food choices.

This study aimed to investigate this by looking at food and drink references in broadcasts aimed at children.

Understanding the influences and patterns on children’s eating habits may help in the development of further measures to improve healthy eating, in addition to targeting the overweight and obesity epidemic. However, this study only provides a small snapshot of food and drink references on child’s TV during a one-week period. It cannot tell us how the many other types of media advertising influence eating patterns, or capture the wider picture of all the lifestyle and environmental factors that are associated with overweight and obesity.

 

What did the research involve?

This research only reviewed the public broadcast channels of the BBC in the UK, and Radio Teilifis Eireann (RTE) in Ireland. These channels were said to be studied as they are “‘public-good’ channels, which aim to inform, educate and empower audiences”.

In July and October 2010, the researchers examined a total 82.5 hours of broadcast on these channels over five weekdays, looking at programmes broadcast between 06.00 and 11.30 on the BBC and between 06.00 and 17.00 on RTE. 

The researchers looked at food or drink references (or cues), defined as “a product being displayed within a food-specific context with potential to be consumed”. Cues were coded by type of product and as healthy or non-healthy (based on the food pyramid).

Healthy foods included breads/grains, cereals, meats, dairy, fruit, vegetables, fish and sandwiches.

Unhealthy foods included fast food/convenience meals, pastries, savoury snacks, sweet snacks/bars, ice cream and candy.

Beverages were coded and grouped as water, juices, tea/coffee, sugar-sweetened or unspecified.

They recorded the context of the cue (e.g. whether it was part of a meal, in the school or home setting, etc), and what motivations and consequences were associated with the food (e.g. as a reward, to relieve thirst or hunger).

 

What were the basic results?

The researchers recorded one food or drink cue every 4.2 minutes, equivalent to 450 on the BBC and 705 on RTE. The total recorded time involving food or drink cues was 4.8% of the total 82.5 hours, covering 3.94 hours and averaging 13.2 seconds per cue.

The most foods most commonly seen could not be grouped into a distinct food group (unspecified, 16.6%), followed by sweet snacks (13.3%), sweets/candy (11.4%) and fruit (11.2%). The most common beverages were also unspecified (35.0%), followed by teas/coffee (13.5%) and sugar-sweetened (13.0%). Unhealthy foods account for 47.5% of specified food cues, and sugar-sweetened beverages for 25%.

Just over a third of the cues were visual, a quarter verbal, and the remainder were visual and verbal combined.

A third of the cues were in the home setting, and in a third of cases, the food or drink was consumed.

Half of the programmes involving food and drink cues involved humans, and half were in animations (human or other). In a quarter of the cases, the motivation for the cue was celebratory/social;  in a quarter, it was to relieve hunger/thirst.

In a third of the cases, the motivation and outcomes associated with the food cue were positive, in half they were neutral, and the remainder were negative.

When comparing the two broadcast channels (only the morning broadcasts when they had data for both), there were significantly more cues on the BBC than the Irish channel; correspondingly, this involved both significantly more healthy cue and unhealthy cues. On RTE, the most common types of foods depicted in 20.5% of cues were unspecified, though on the BBC sweet snacks topped the chart, at 19%.

RTE contained significantly more cues for breads/grains, condiments and breakfast pastries, while BBC had significantly more for fruit, sweet snacks and ice cream. For beverages, it was most commonly unspecified in both countries.

BBC included more visual cues, while RTE had more verbal. BBC also had more animated characters, while RTE had more human. For both countries, the motivation was most often celebratory/social, followed by hunger/thirst. Health was not recorded as a cue motivation on the BBC, while it was in 6.2% of RTE cues.

 

How did the researchers interpret the results?

The researchers concluded that, “This study provides further evidence of the prominence of unhealthy foods in children’s programming. These data may provide guidance for healthcare professionals, regulators and programme makers in planning for a healthier portrayal of food and beverages in children’s television”.

 

Conclusion

This study provides a snapshot of the food and drink cues/references contained in children’s TV programmes on BBC and RTE over five weekdays, totalling 82.5 hours of broadcasting.

The research demonstrates the frequency of cues, the types of food and drink associated, and the motivations for the food cue.

This includes the observation that unhealthy foods accounted for just under half of specified food cues, and sugar-sweetened beverages accounted for a quarter.

The context of the food and drink cue was mostly positive, with celebratory/social motivations the most common.

Importantly, this study can’t tell us whether these food and drink cues actually have any direct influence on a child’s food and drink requests or their eating patterns. While an association between a child’s duration of TV viewing and overweight/obesity has previously been established, this is unlikely to be a result of a single factor, such as exposure to food and drink cues in TV programmes. Other factors – most notably, lack of physical activity while watching TV, and possibly the mindless eating snacks while watching – are likely to have a big influence.

As both BBC and RTE are publicly funded broadcasters, it is unlikely that any unhealthy food cues were included for commercial reasons (notorious examples include the McDonalds “Hamburglar” or “Tony the Tiger”, which was used to sell sugared flakes).

The idea that food is a treat or celebration has long been part of children’s fiction, such as the Famous Fives' “lashing of ginger beer and ice creams”.

It would be interesting to take a broader look at the content across TV channels and over a broader period of time, and also compare the content in programmes targeted at children compared to teenagers and adults.

The food and drinks in this study were categorised into broad groups “healthy” or “unhealthy” groups, but this may not necessarily be the case. For example, healthy foods included breads/grains, cereals, meats, dairy and sandwiches. However, in all of these food groups, you can get many different “healthy” and “unhealthy” versions of each.

Ultimately, while television may be useful as an occasional babysitter, it is no substitute for parenting.

Teaching your child healthy habits at an early age increases the chances that such habits will persist into adulthood.

Read more about encouraging healthy eating in children.

Analysis by Bazian. Edited by NHS ChoicesFollow Behind the Headlines on TwitterJoin the Healthy Evidence forum.

Links To The Headlines

Children bombarded with unhealthy eating messages on TV, experts warn. The Independent, July 4 2014

Children's TV 'packed with junk-food references'. BBC News, July 4 2014

Links To Science

Scully P, Reid O, Macken A, et al. Food and beverage cues in UK and Irish children—television programming. Archives of Disease in Childhood. Published online June 30 2014

Categories: Medical News