Medical News

Women over 50 warned not to skip smear tests

Medical News - Wed, 01/15/2014 - 14:00

"Women aged 50 and older are being warned of the dangers of skipping smear tests," BBC News reports, as a UK study into the impact of cervical cancer screening found that our current screening practices seem to work.

In England women are invited to have cervical cancer screening every three years between the ages of 25 and 49 (when rates of the cancer are at its peak), and every five years between the age of 50 and turning 65.

This research investigated whether it was useful to continue to screen for cervical cancer after the age of 50, and whether 64 was an appropriate age to stop screening. The short answer to both questions was yes.

A total of 1,341 women aged 65 to 83 were diagnosed with invasive cervical cancer over a five-year period in England and Wales. The screening history of these women was compared with those of 2,646 women of the same age without cervical cancer.

Women who did not attend screening tests as recommended were six times more likely to develop cervical cancer at these ages compared with women who did.

The research also indicated screening is appropriate up until the age of 64, but may be of limited benefit beyond 69.

However, given increasing life expectancy, screening in older women might be justified in the future. There is evidence that rates of cervical cancer can experience a smaller peak in women aged between 80 and 84.

NHS cervical screening for women aged 50 to 64 is free to attend.

 

Where did the story come from?

The study was carried out by researchers from Barts and The London School of Medicine and Dentistry and was funded by Cancer Research UK.

It was published in the peer-reviewed medical journal PLOS Medicine. The study was published as an open access document, meaning anyone can view the publication in full free online.

The media generally reported the story accurately, including expert commentary to inform women that screening usually picks up abnormal cells at an early stage when they can be removed to prevent the onset of cancer.

However, the reporting was skewed towards discussing the greater risks associated with not taking up cervical screening for women over 55, rather than whether 65 was an appropriate age to stop offering screening.

The second question was actually the primary aim of the study, as offering screening to a population that actually had no or very little risk of a specific disease would waste both people's time and NHS resources.

 

What kind of research was this?

This was a case-control study of women in the UK who developed cervical cancer over the age of 65 to see how effective cervical screening is in this older age group. It aimed to see if it is reasonable to stop routine cervical cancer screening at the age of 65.

A case-control study compares the characteristics of all the cases of a disease in a population with the characteristics of matched individuals without the disease.

 

What did the research involve?

Researchers looked at the GP records of women who were diagnosed with cervical cancer after the age of 65 and women of the same age who were not.

The cases were women registered with an NHS GP and diagnosed with cervical cancer in England between April 1 2007 and March 31 2012, and in Wales from January 1 2007 to December 31 2009.

Two women of the same age and place of residence were randomly selected using a computer programme to act as controls. The researchers chose one woman from the same GP practice and one woman from a different GP practice in case the uptake of screening was dependent on the GP.

Local NHS staff obtained the screening history data from NHS cervical screening records and made the data anonymous before sending it to the researchers.

The researchers excluded women aged 60 years or over on January 1 1988, as they may not have been invited to the NHS cervical screening programme.

They used appropriate statistical methods to determine the risk of developing cervical cancer at 65 years or older with each type of screening method result between the ages of 50 and 64.

The researchers performed additional "sensitivity" analysis to try to account for unknown factors that might have had an impact on the results, such as smoking or the number of sexual partners. Both of these are known risk factors for cervical cancer.

 

What were the basic results?

A total of 1,341 women aged between 65 and 83 were diagnosed with invasive cervical cancer in England and Wales. Similar numbers of women (range 404 to 435 women) were diagnosed in each five-year age bracket from 65 to 79, but relatively few (just 97 women) were aged 80 to 83.

The screening history of these women was compared with that of 2,646 women of the same age without cervical cancer.

The main findings were:

  • women with adequate negative screening at age 50 to 64 had one-sixth of the risk of cervical cancer aged 65 to 83 compared with women who were not screened
  • rates would have been 2.4 times higher if there was no screening programme for this age group
  • screening at least every 5.5 years between the ages of 50 and 64 was associated with a 75% lower risk of cervical cancer
  • the effect of screening reduces with age between the ages of 65 and 79 – the risk in well-screened women was half that of unscreened women by the age of 80

 

How did the researchers interpret the results?

The researchers concluded that, "Screening up to the age of 65 greatly reduces the risk of cervical cancer in the following decade, but the protection weakens with time and is substantially less 15 years after the last screen.

"In the light of increasing life expectancy, it would seem inappropriate for countries that currently stop screening between the ages of 60 and 69 to consider reducing the age at which screening ceases. To the contrary, consideration should be given to cost effective ways of increasing the age of the last screening."

 

Conclusion

This well-designed study presents valuable data on the benefits of cervical cancer screening in older age groups.

The researchers point out that their study was limited in that they did not have information on important risk factors for cervical cancer, such as smoking.

They attempted to account for this and other unknown confounders through additional sensitivity analysis. However, this may not have been adequate to account for all of the other risk factors not measured, and so introduces a degree of uncertainty to the results.

The researchers also suggest that the changing nature of cervical screening may have influenced the results. One such change is the introduction of tests for high-risk types of human papilloma virus (HPV). These are believed to cause most cervical cancers, as well as other risk factors such as smoking and low immunity.

These tests were not available for the women in this study and the researchers report that no long-term (15 to 20-year) studies have looked at the risk of cervical cancer after a negative HPV test. This may have a bearing on screening requirements for older women in the future.

The future effects of the recently introduced HPV vaccine may also need to be taken into account in the years to come, although the current vaccine does not protect against all strains of HPV.

For now, though, the results of this study should encourage women between the ages of 50 and 64 to take up the opportunity for cervical cancer screening that the NHS provides.

 

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter. 

Links To The Headlines

Women over 50 urged not to skip smear tests. BBC News, January 15 2014

Over 55s ignoring cervical cancer risk: They face six times the danger of those who are screened. Mail Online, January 14 2014

Women over 50 who skip smear tests more likely to get cancer. The Guardian, January 15 2014

Links To Science

Castañón, A, Landy R, Cuzick J, et al. Cervical Screening at Age 50-64 Years and the Risk of Cervical Cancer at Age 65 Years and Older: Population-Based Case Control Study. PLOS One. Published online January 14 2014

Categories: Medical News

Is sugar causing the obesity 'epidemic'?

Medical News - Wed, 01/15/2014 - 13:44

Sugar hit the headlines last week when the Daily Mail and The Independent led with the quote “Sugar is the new tobacco”. Many news outlets focused on a reported link between high sugar consumption and the rise in obesity and diabetes.

The reports stem from the newly formed campaign group Action on Sugar, whose well-timed press release coincides with New Year's resolutions and January diet crazes.

Action on Sugar warns that as well as being “a major cause of obesity”, there is “increasing evidence that added sugar increases the risk of developing type 2 diabetes, metabolic syndrome and fatty liver”.

In a separate story, several newspapers also highlighted an expert's perhaps surprising opinion that fruit juice contains so much sugar that it should no longer count as one of the 5 A DAY portions of fruit and vegetables.

"I would support taking it out of the 5 A DAY guidance,” Professor Susan Jebb is quoted as saying.

“Fruit juice isn’t the same as intact fruit and it has got as much sugar as many classical sugar drinks," she said.

 

What is Action on Sugar?

Action on Sugar is a group of specialists concerned with sugar and its effects on health. It says it is working to reach a consensus with the food industry and the government over:

  • the harmful effects of a high-sugar diet
  • reducing the amount of sugar in processed foods

It stresses the importance of protecting children from this “public health hazard” and calls for the food industry to “immediately reduce the amount of sugar that they are adding, particularly to children’s foods, and stop targeting children with massive advertising for high-calorie snacks and soft drinks”.

Action on Sugar is supported by 18 expert advisers. Its chairman is Professor Graham MacGregor, professor of cardiovascular medicine at the Wolfson Institute, Queen Mary University of London. Professor MacGregor also chairs Consensus Action on Salt and Health.

 

What is Action on Sugar calling for?

Action on Sugar believes the link between calories and obesity is caused in part by high sugar consumption, and that not enough is being done to tackle what they call “the obesity and diabetes epidemic”. It says that the right approach is to “target the huge and unnecessary amounts of sugar that are currently being added to our food and soft drinks”. It highlights the work that is already being carried out by food manufacturers to reduce the amount of salt that is added to processed foods.

Salt intake is estimated to have fallen in the UK by 15% (between 2001-2011) and the salt contained in most products in the supermarkets has been reduced by 20-40%. This is calculated to have led to at least 6,000 fewer strokes and heart attack deaths a year, and a reported healthcare saving cost of £1.5billion, according to Action on Sugar.

Action on Sugar says that a similar programme can be developed to gradually reduce the amount of added sugar in food and soft drinks (with no substitution for alternative sweeteners or sugars) by setting targets for foods and soft drinks. Action on Sugar has calculated that a 20-30% reduction in sugar added by the food industry over the next three to five years is “easily achievable”. This, they say, would result in a reduction in calorie intake of approximately 100kcal (420kilojoules) a day for everyone and more in those people who are particularly prone to obesity.

Professor Graham MacGregor said: “We must start a coherent and structured plan to slowly reduce the amount of calories people consume by slowly taking out added sugar from foods and soft drinks. This is a simple plan which gives a level playing field to the food industry, and must be adopted by the Department of Health to reduce the completely unnecessary and very large amounts of sugar the food and soft drink industry is currently adding to our foods.”

 

How did critics receive Action on Sugar’s claims?

The organisation Sugar Nutrition UK has rejected Action on Sugar’s claims, saying that they "are not supported by the consensus of scientific evidence”.

Sugar Nutrition UK cites a review on sugar and obesity published in 2013 and funded by the World Health Organization, which they say concluded that “any link to body weight was due to overconsumption of calories and was not specific to sugars”.

Sugar Nutrition UK, which is largely funded by sugar manufacturers, also disagrees that reducing the amount of sugar in foods will always result in a reduction of calories. “In most cases the sugar will need to be replaced by another ingredient and the reformulated recipes can contain more calories than the original,” it says.

It also argues that, “the balance of available evidence does not implicate sugar in any of the so-called 'lifestyle diseases', such as diabetes”.

 

Is sugar really “as harmful as tobacco”?

The headlines comparing sugar to tobacco were prompted by a quote from Simon Capewell, professor of clinical epidemiology at the University of Liverpool, in Action on Sugar's press release.

Professor Capewell said: “Sugar is the new tobacco. Everywhere, sugary drinks and junk foods are now pressed on unsuspecting parents and children by a cynical industry focused on profit not health.”

Links To The Headlines

Sugar and obesity headlines

Britain's obesity crisis: time for shock tactics. The Times, January 13 2014

Sugar is the new tobacco: Health chiefs tell food giants to slash levels by a third. Daily Mail, January 9 2014 

'Sugar is enemy number one for causing diabetes and obesity', say experts. Daily Express, January 9 2014

Campaigners vow to cut sugar in food. BBC News, January 9 2014

'Sugar is the new tobacco': Cuts to amounts hidden in food could halt obesity epidemic, claim doctors. The Independent, January 9 2014

Sugar is as dangerous as alcohol and tobacco, warn health experts. The Daily Telegraph, January 9 2014

Obesity experts campaign to cut sugar in food by up to 30%. The Guardian, January 9 2014

 

Fruit juice and 5 A DAY headlines

Obesity tsar calls for tax on juice, The Sunday Times, January 12 2014

Wean yourself off orange juice, says government health tsar. The Daily Telegraph, January 12 2014

Fruit juice 'shouldn't count in your 5 a day': Some brands have more sugar than cola says obesity tsar. Daily Mail, January 13 2014

Fruit juice should not be part of your 5 A DAY, says government adviser, The Guardian, January 12 2014

Categories: Medical News

New warnings issued over deadly DNP 'diet drug'

Medical News - Wed, 01/15/2014 - 13:30

“The families of two young people who died after taking the fat-burning pill DNP are campaigning for it to be classified as a class-C drug to criminalise its possession and supply in the hope of preventing more deaths” The Guardian reports.

This is the latest in a series of warnings about the dangers of 2,4-Dinitrophenol (DNP), which has officially been linked to 60 deaths worldwide.

 

What is DNP?

DNP is a combination of compounds that was widely used during the early 20th century in a range of industrial processes.

In 1933, an American researcher discovered that when taken by humans, DNP dramatically speeds up the metabolism leading to rapid weight loss. It was subsequently marketed as a weight loss drug. It was quickly withdrawn from the market, however, after it was found to be highly toxic, causing significant side effects and in some cases, deaths.

In 1938 the American Food and Drug Agency issued a statement saying DNP was “extremely dangerous and not fit for human consumption”.

It appears that DNP has becoming increasing popular during the last decade among bodybuilders for its "quick-fix" ability to lead to rapid weight loss. Presumably this information was spread both by word-of-mouth as well as via internet forums and message boards.

 

Why is DNP so dangerous?

One of the risks of DNP is that it accelerates the metabolism to a dangerously fast level. Our metabolic system operates at the rate it does for a reason – it is safe. Speeding up the metabolism may help burn off fat, but it can also trigger a number of potentially dangerous side effects, such as:

  • fever
  • dehydration
  • nausea
  • vomiting
  • restlessness
  • flushed skin
  • excessive sweating
  • dizziness
  • headaches
  • rapid breathing
  • rapid or irregular heartbeat

The combination of these side effects can have an extremely damaging effect on the body and can result in coma and, as we have seen, death.

Long-term use can lead to the development of cataracts and skin lesions and may cause damage to the heart and nervous system. There is also evidence from animal studies that DNP is carcinogenic (cancer causing) and increases the risk of birth defects.

 

Is DNP legal?

No. It is illegal to sell DNP as a weight loss drug and doing so could place you at risk of criminal sanctions.

 

What is being done about DNP?

Links To The Headlines

DNP victims' families lead fight to have fat-burning drug classified. The Guardian, January 14 2014

Victims' families call for killer diet drug ban: Fat-burning pills have caused 60 deaths worldwide. Mail Online, January 15 2014

Teenage rugby star took deadly diet pill for beach holiday six pack, say parents. Metro, September 17 2013

Chris Mapletoft’s parents: how was it so easy to buy toxic diet pills? The Times, September 17 2013

Tragedy of the gifted rugby player, 18, who died after buying deadly 'fat-burning' pills online. Daily Mail, September 16 2013

Police probe ‘diet pill’ death of boy, 18. Daily Express, September 16 2013

Deadly online diet pills claim another British life. Daily Star, September 16 2013

Teenage rugby star killed by online diet pills. The Daily Telegraph, September 15 2013

Teenage rugby star killed by toxic online diet drug. Metro, September 15 2013

The deadly trail of the killer slimming drug DNP. The Daily Telegraph, April 28 2013

Sarah Houston family call for ban on DNP slimming drug. BBC News, April 23 2013

Links To Science

Grundlingh J, Dargan PI, El-Zanfaly M, Wood DM. 2,4-Dinitrophenol (DNP): A Weight Loss Agent with Significant Acute Toxicity and Risk of Death. Journal of Medical Toxicology. September 11 2011

 

Categories: Medical News

Study examines quick and simple 'dementia test'

Medical News - Tue, 01/14/2014 - 13:31

"Alzheimer's disease: 15-minute test could spot early sign of dementia," reports The Daily Telegraph. The news is based on a US study that examined the so-called Self-Administered Gerocognitive Examination (SAGE) as a screening tool for mental decline.

SAGE assesses a variety of people's mental functions and can be completed using just a pencil and paper almost anywhere – speed and simplicity are often advantageous for screening tests. The SAGE score could help a doctor decide whether to order further tests, or it could be used to see if there are any changes in a person's mental function over time.

In this study, researchers assessed whether community-based SAGE screening for the over-50s was feasible. They found that they could screen a large number of people in the community using the test. Of those screened, 28.4% were identified as having mental decline based on previously published standards.

However, the researchers did no further testing to determine whether people scoring in the mild cognitive impairment or dementia range had evidence of these conditions. The test also was not compared with other existing cognitive tests.

It is important to note that despite suggestive media headlines, this test alone cannot formally diagnose Alzheimer's disease or any other form of dementia.

As yet, the balance of benefits and harms of screening the general population for mental decline or dementia remains unclear.

If you are worried about your or a friend or relative's memory, talk to your GP and sign up to the Dementia Information Service weekly emails.

 

Where did the story come from?

This cross-sectional study was carried out by researchers from the Ohio State University Wexner Medical Center. The source of funding was not reported.

It was published in the peer-reviewed Journal of Neuropsychiatry and Clinical Neurosciences.

This research was widely covered in the media. Many hailed SAGE as a 15-minute test that could spot Alzheimer's disease.

However, the researchers did not examine how good SAGE was at detecting mild cognitive impairment (mental decline) or dementia. They also did not carry out further tests to confirm the diagnosis of a specific condition, such as Alzheimer's disease.

Instead, the study examined whether it was possible to use SAGE in the community to detect cognitive decline. If successful, it could potentially be used to help identify people who may need to see healthcare professionals for advice or further testing.

 

What kind of research was this?

This study investigated the characteristics and usefulness of the Self-Administered Gerocognitive Examination (SAGE) as a screening test.

SAGE is used to identify people with mild cognitive impairment and dementia in the community. It has questions on six areas:

  • orientation (such as the date)
  • language (verbal fluency and picture naming)
  • reasoning and computation (abstraction and calculation)
  • visuospatial (3D construction and clock-drawing)
  • executive ("modified Trail B", a kind of "dot-to-dot", and other problem-solving tasks)
  • memory

There are four slightly different versions of SAGE, designed to avoid the effects of practice (getting a better score because you've done the same test multiple times) and prevent cheating when it is given to large groups of people at the same time.

People with scores between 22 (maximum score) and 17 are likely to have normal cognition, those with scores of 16 and 15 are likely to have mild cognitive impairment, and people with scores of 14 or less are likely to have dementia.

Doing the test for the first time represents the "baseline" from which changes in score can be monitored.

 

What did the research involve?

The study recruited 1,047 people over the age of 50 from a range of locations through events at senior centres, health fairs, educational talks, independent and assisted living facilities, and via newspaper adverts.

People were given the SAGE test to fill in, which was then collected and graded. Large groups of people sometimes completed the test at the same time.

Administrators would provide people with the score on the spot and gave out written information on the test. People were advised to show their score to their doctor for interpretation and any further screening or tests.

 

What were the basic results?

The average SAGE score was 17.8. On the basis of their SAGE score, 71.6% of those tested had normal cognition, 10.4% had mild cognitive impairment (mild mental decline), and 18% had dementia.

Older age and lower education were associated with lower total SAGE scores.

 

How did the researchers interpret the results?

The researchers described screening people using SAGE as "feasible, practical, reliable, and efficient".

They said: "SAGE is able to rapidly screen large numbers of individuals in the community at the same time because of its self-administered feature and having four interchangeable forms that reduce the temptation of dishonesty.

"In our study, 28.4% of those screened were identified as having cognitive impairment, based on previously published standards for the SAGE test. Finding these individuals through screening can 'start the conversation' about cognitive impairment with their primary care doctors and potentially lead to earlier evaluation, management, and treatments.

"It also potentially makes it easier to find research participants at the early and pre-dementia stages, to evaluate new therapies. Future studies need to compare SAGE with cognitive screening measures that require more administration time," they added.

 

Conclusion

This study examined SAGE as a screening tool. Researchers found that a large number of people could be screened in the community for mental decline using SAGE.

Of those screened, 28.4% were identified as having mental decline based on previously published standards for the SAGE test.

No further testing (for instance, validated cognitive tests or investigations such as brain scans) was performed to determine whether people whose scores suggested that they may have mild cognitive impairment or dementia actually had clinical evidence of these conditions, and the test was not compared with other existing cognitive tests.

It is therefore unclear how accurate and reliable this test may be as an indicator of mild cognitive decline (mental decline) or dementia. Despite suggestive media headlines, this test alone cannot diagnose Alzheimer's or any other form of dementia.

In addition, further studies are required to determine whether there are any benefits or harms in screening the general population for mental decline. Some in the medical profession are troubled by the thought of mass screening for dementia when there are currently few helpful therapeutic options.

If you are worried about your own or a loved one's memory, visit your GP. You may find the NHS Choices Dementia Information Service useful if you or a friend or relative have recently been diagnosed with dementia.

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter.

Links To The Headlines

Alzheimer's disease: 15-minute test could spot early sign of dementia. The Daily Telegraph, January 13 2014

Can you answer these five questions? The 15-minute home test that spots signs of Alzheimer's. Daily Mail, January 13 2014

Self-test could provide an early indication of the onset of dementia. Daily Mirror, January 13 2014

Dementia: 15-Minute Test To Spot Signs Early. Sky News, January 13 2014

Links To Science

Scharre DW, et al. Community Cognitive Screening Using the Self-Administered Gerocognitive Examination (SAGE). Journal of Neuropsychiatry and Clinical Neurosciences. Published online January 13 2014

Categories: Medical News

More Brits than ever are living with cancer

Medical News - Tue, 01/14/2014 - 13:31

"UK’s annual cancer diagnosis numbers rise by 50,000 in a decade,” reports The Guardian.

The headline is based on new figures released by Cancer Research UK, which show that in 2011 (the latest available statistics) 331,487 people in the UK were diagnosed with cancer. In 2001 there were 283,000 diagnoses. The current figures mean there are about 524 cases of cancer per 100,000 people.

The figures are published as Cancer Research UK continues its campaign to raise awareness of the importance of research in beating cancer and reducing its impact.

 

What did Cancer Research UK find?

Cancer Research UK found that the overall rates of people being diagnosed with cancer have climbed by a more than a third (35%) between 1975 and 2011. The age-standardised incidence rates, (which take into account how many old or young people are in the population so that differences seen are not due to difference in the proportion of young and old people) increased from around 295 per 100,000 in 1975 to almost 400 per 100,000 in 2011.

Importantly, the charity found that four cancers account for more than half of all new cases – breast, lung, bowel and prostate.

Around 159,000 people died from cancer in the UK in 2011. The death rate from cancer is falling. In 1975 there were 215 deaths per 100,000 people (measured using an age-standardised mortality rate) compared to 170 cases per 100,000 in 2011.

 

What could be causing the increase in cancer diagnoses?

Age is the biggest risk factor for cancer. And as people are tending to live longer, this is contributing to the higher numbers of cancers found.

Smoking, being overweight, a diet low in fruit and vegetables, and alcohol consumption are the four lifestyle factors linked to the most cancers.

Cancer Research does not discuss other possible causes for the increase in the number of diagnoses. And it is possible the changes could be a reflection of changes in lifestyle factors (such as increased prevalence of overweight and obesity), but also due to improved cancer awareness and diagnostic methods compared to the 1970s. One encouraging point is that deaths from cancer are decreasing, which may reflect earlier diagnosis and treatment, and improved treatments.

 

What does Cancer Research UK say about the figures?

Dr Harpal Kumar, Cancer Research UK's chief executive, said: "These figures reinforce the vital need for more research to better prevent, treat and cure cancer. As the population ages, more people than ever before will be told: 'you have cancer'." 

 

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter.

Links To The Headlines

UK's annual cancer diagnosis numbers rise by 50,000 in a decade. The Guardian, January 14 2014

More Britons stricken by cancer... but survival rate is better than ever. Daily Express, January 14 2014

50,000 more people a year are told they have got cancer: Huge increase in the past decade blamed on obesity and alcohol consumption. Daily Mail, January 14 2014

UK cancer diagnoses top 330,000. BBC News, January 14 2014

Cancer: Ageing Population Blamed For Increase. Sky News, January 14 2014 

Categories: Medical News

Coffee may aid aspects of memory, study finds

Medical News - Mon, 01/13/2014 - 16:28

With exams on the horizon for many students, the somewhat dubious claim made by The Independent is that the "Secret to passing exams is [a] large espresso after revision".

But while the study it reports on did find an association between caffeine intake and enhanced memory, the effect was inconsistent.

The study, which involved 160 people between the ages of 18 and 30, showed that giving a dose of 200mg caffeine pills (roughly equivalent to two mugs of instant coffee) enhanced their ability to distinguish between subtly different objects one day after studying them.

However, no enhancing effects were found when recalling which objects were identical to the day before and which were new, so the memory enhancement effect was not consistent across the elements tested.

This may be a sign that caffeine enhances memory in a very specific way. Alternatively, the one significant result may be a chance finding and there really is no effect.

The study did not address whether caffeine has any effect upon children's learning or retention at school, or whether caffeine could have any effect upon older adults with diseases affecting their memory, such as Alzheimer's disease.

These results need to be replicated in further research, as the effect observed may be a chance finding.

If you do have a big exam coming up, we would recommend that you stick to plain old tap water instead. As the lead author of the study warns, "Caffeine can have side effects like jitteriness and anxiety in some people. The benefits have to be weighed against the risks".

 

Where did the story come from?

The study was carried out by researchers from Johns Hopkins University and the University of California. The researchers were funded by the US National Institute on Aging, the US National Science Foundation, and Johns Hopkins University.

It was published in the peer-reviewed journal Nature Neuroscience.

The media generally reported the story accurately, although many of the headlines hyped the strength of the evidence provided in the study. For example, the Sunday Mirror's claim that "Scientists reveal caffeine provides huge boost to your short-term memory" is groundless.

However, BBC News did include a particularly useful quote from the main study author, Professor Michael Yassa, who cautioned that the findings "do not mean people should rush out and drink lots of coffee, eat lots of chocolate, or take lots of caffeine pills".

The negative effects associated with caffeine, such as irritability and insomnia, also need to be considered in weighing up the potential benefits and harms. The amount and quality of sleep we get can also influence learning and memory, so there may be some trade-offs in terms of the potential benefits of caffeine.

 

What kind of research was this?

This was a double-blind randomised controlled trial looking at the effect of caffeine on memory.

The researchers say that some studies have shown caffeine enhances short-term cognitive (brain) performance, but most long-term studies found little or no effect.

However, these studies gave people caffeine before they tried to learn or memorise objects or tasks. This means the other effects of caffeine, such as increased wakefulness or arousal, may impact learning in ways other than enhancing memory, and could cloud the findings specifically on memory. 

The difference with the new research was that it gave people caffeine after the learning phase in an effort to investigate any potential effects it had on memory in isolation. That is, whether caffeine intake after a specific cognitive task helps "fix" the resulting piece of information in the memory.

 

What did the research involve?

The researchers showed 160 healthy participants individual pictures of objects to study. Half the group was randomly selected to receive 200mg of caffeine and the other half was given a placebo pill.

The participants were tested on their recollection of the objects 24 hours later. This test included objects they had seen the previous day (targets), some new objects (foils), and some objects that were visually similar but subtly different to the original objects (lures).

Examples given of "targets" and the corresponding "lures" included images of saxophones and seahorses. For each image, the participants were instructed to decide whether the image was "old", "new" or "similar".

Saliva samples were taken immediately after the participants studied the objects, and again one, two, three and 24 hours after they received the caffeine or placebo so that the researchers could study how the caffeine was broken down in the body.

Participants were described as "caffeine-naïve", suggesting they didn't usually have a caffeine intake in their diets, but this was not described explicitly. Those who consumed more than 500mg caffeine a week were excluded from the study.

The study was described as double-blind, meaning neither the participants nor the people assessing their memory knew which group (caffeine or placebo) they had been randomly assigned to.

The main analysis compared how well the two groups identified:

  • targets – identical objects they had seen the previous day
  • foils – new objects they had not seen the previous day
  • lures – similar, but not identical, objects to the previous day

 

What were the basic results?

Participants who received caffeine were more likely to correctly identify the lure objects compared with participants who received the placebo.

There were no differences between those who received caffeine and those who received placebo in the recognition of target or foil objects.

To rule out any effects of caffeine on memory retrieval, the authors conducted a second delayed caffeine experiment. They gave participants caffeine one hour before the memory test (still 24 hours after the initial study session).

The authors observed no significant memory enhancement in those given caffeine compared with placebo. They interpreted this as suggesting that caffeine does not affect any other aspect of memory retention performance.

They also studied different doses of caffeine to see what was best for memory and if there was a dose-response relationship. They found:

  • the dose-response relationship did not appear to be linear – that is, higher caffeine doses did not improve memory in a simple relationship
  • 200mg was better than placebo and 100mg, but it was no different to 300mg
  • the dose-response curve was described as an "inverted U", meaning the optimum dose was in the middle of the 100, 200 and 300mg range tested, with a diminishing effect at the higher and lower doses

The researchers concluded that at least 200mg was required to observe the enhancing effect of caffeine on memory.

 

How did the researchers interpret the results?

The authors concluded that the lack of difference in identifying identical objects (hits) and recognising when the objects were new (foils) meant that basic recognition memory was unaltered by caffeine.

The slightly better performance in the caffeine group when identifying lures was interpreted as meaning that, "Caffeine enhanced consolidation of the initial study session such that discrimination during retrieval was improved".

 

Conclusion

This study showed that giving a 200mg dose of caffeine to people who don't usually consume it enhanced their ability to distinguish between subtly different objects one day after studying them. However, no effects were found when identifying identical or new objects, so the memory enhancement effect was not consistent.

It is unclear what benefit this very specific effect would lead to in a real-life situation, such as an exam, if replicated in a wider population.

The result may also be a chance error and caffeine actually has no effect on memory. We will only be able to know if the effects are real if the study is repeated more times in different and larger populations.

This study also has a number of other limitations to consider when interpreting its findings:

  • The study sample was relatively small, with 160 participants.
  • The study sample was relatively young (mean age 20 years) and excluded those aged under 18 or over 30. It therefore does not address whether caffeine has any effect on a child's ability to learn or remember, or whether caffeine may have any effect on older adults with diseases affecting memory, such as Alzheimer's.
  • The study subjects were aware they were participating in a study of caffeine. However, a survey of the participants suggested they didn't know which group they had been assigned to (caffeine or placebo), indicating the blinding element of the trial was effective and unlikely to bias the results.
  • The sample sizes were small in the experiments comparing different caffeine doses (sometimes just 10 people), increasing the chance that no differences would be found between groups, even if real differences existed. These findings should therefore be treated with a pinch of salt.
  • Participants with high caffeine consumption of more than 500mg per week were excluded from the study. The potential additional memory enhancing effects may be different or absent in people already consuming high levels of caffeine.

The bottom line is that the study results need to be replicated, as the effect observed may be a chance finding.

Readers should not rush out and consume large amounts of caffeine in the hope it will boost their memory based on the results of this study. Until further studies prove these findings, there is currently no sure-fire short-cut to revision other than hitting the books on a regular basis.

 

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter.

Links To The Headlines

Swot shot: Secret to passing exams is large espresso after revision. The Independent, January 12 2014

How coffee can perk up your memory: Drinking a strong mug after a learning session can improve recall. Mail Online, January 12 2014

Caffeine pill 'could boost memory'. BBC News, January 12 2013

Scientists reveal caffeine provides huge boost to your short-term memory. Sunday Mirror, January 12 2014

Study: coffee enhances long-term memory retention. Wired, January 13 2014

Links To Science

Borota D, Murray E, Keceli G, et al. Post-study caffeine administration enhances memory consolidation in humans. Nature Neuroscience. Published online January 12 2014

Categories: Medical News

Report warns of a looming UK obesity crisis

Medical News - Mon, 01/13/2014 - 13:00

“Estimates that half the UK population will be obese by 2050 'underestimate' the problem, a report has claimed,” according to BBC News, while the Daily Mail describes how a “bombshell report reveals true scale of crisis” around the nation’s bulging waistlines.

The report, published by the National Obesity Forum, calls for hard-hitting awareness campaigns similar to anti-smoking advertisements. The State of the Nation’s Waistline report by the National Obesity Forum, focused on the core issue of how a previous Government report predicting half of Britons will be obese by 2050 – a startling and troubling stat in itself – may be an underestimate.

The BBC reports how the forum described the original report as “shocking at the time” but that it “may now underestimate the scale of the problem”.

Based on the data provided in the report, as well as associated evidence, a case could well be made that obesity is to the 21st century as tobacco was to the 20th century. That is, an entirely preventable cause of chronic diseases and premature death.

 

Who produced the report?

The new report entitled, State of the Nation’s Waistline, was produced by the National Obesity Forum, a charity raising awareness of obesity in the UK and promoting ways in which it can be addressed.

The report is being released to coincide with the start of National Obesity Awareness Week 2014. This is a campaign to raise public awareness of obesity and the ways it can be tackled at governmental levels through the promotion of some policies and changes to others, and at a personal level through achievable and manageable lifestyle changes.

 

What evidence did the report consider?

The report aimed to address three main areas:

  • Analyse existing research to offer an assessment on the scale of obesity in the UK and to consider how this might either increase or decrease in the future.
  • Summarise and review UK policy regarding weight management and obesity, and to provide comment on its effectiveness.
  • To offer recommendations as to what changes are necessary to reduce obesity levels in the UK.

It drew on evidence from a range of sources, including:

  • the Foresight Report (2007) which concluded that half the UK population could be obese by 2050 at a cost of £50bn per year
  • research and official statistics published by the Health & Social Care Information Centre – a national provider of high-quality health and social care information
  • data from national and local health surveys including The Health Survey for England (2010)
  • primary research studying trends in obesity in the UK

 

What were the main conclusions?

The main conclusion was that the already worrying predictions made in the 2007 Foresight Report “could be optimistic and could be exceeded by 2050” meaning they think it is possible half of Britain’s population will be obese before 2050, earlier than the original report predicted.

The revised outlook came from figures showing that obesity levels among adults and children are generally rising fast, and that people are getting fatter in later life. However, they note that there has been some fall in the number of obese and overweight children in their final year of primary school in England for the first time in six years (based on a 2013 report) but that childhood obesity still remains “worryingly high”.

Additionally, the levelling off of upward obesity rates tends to be among children from the most affluent areas, obesity levels in children from deprived areas remain high.

In summary, while there are glimmers of hope, the overall picture is bad and may be worse than previously assumed.

The report acknowledges current government approaches to the obesity problem, including the Change4Life Programme and the Public Health Responsibility Deal, but highlights “significant gaps that must be addressed”.

For example, they highlight how people’s intake of salt, trans-fats and sugar remains enormously important. Interestingly it also draws attention to what it describes as a “body of evidence demonstrating the effectiveness of proper hydration (what and how much you should drink) as part of a broader approach to healthy living rather than an emphasis on healthy eating specifically”.

People who drink a lot of carbonated sugary drinks or alcohol may be unaware about how this can impact on their daily calorie intake. For example, a single 330ml can of cola amounts to around 7% of the recommended daily calorie intake for a woman. While a pint of export lager contains around 260 calories; over 10% of the recommended calorie amount for a man (read more about the calories in alcohol).

Drinking habits have not typically been part of the public discussion of tackling obesity, so highlighting this issue to the public is new.

 

What does the report recommend?
  • Harder-hitting campaigns, similar to those for anti-smoking.
  • GPs should be encouraged to engage with patients on obesity and weight management issues.
  • GPs should be encouraged and indeed required to make every contact with patients count. Very few patients will cite obesity or weight management as the reason for seeing their GP so GPs need to be the ones to talk about weight issues.
  • Greater training of primary healthcare professionals on obesity and weight management.
  • Government initiatives should include a greater focus on the importance of good hydration in weight management and health outcomes. By focusing primarily on healthy eating and food choices, existing guidance overlooks the undermining effect that poor hydration choices can have.
  • Greater focus needs to be devoted to strategies supporting individuals who are already obese. Current government policy is focused largely on prevention.
  • The introduction of compulsory physical education in schools is positive. However, greater promotion of physical activity outside of educational settings is also key.

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter.

Links To The Headlines

Obesity crisis: Future projections 'underestimated'. BBC News, January 13 2014

Obesity UK - It's worse than feared: Bombshell report reveals true scale of crisis. Daily Mail, January 13 2014

Britain's obesity epidemic worse than feared. The Sunday Telegraph, January 12 2014

Obesity crisis: More than half of British population set to be obese by 2040. Metro, January 13 2014

Obesity: Scale Of Problem 'Underestimated'. Sky News, January 13 2014

Obesity in UK 'could be far worse than predicted'. The Guardian, January 13 2014

Claim that half overweight by 2050 ‘underestimates obesity problem’. The Independent, January 13 2014

Calls for action to avoid 'doomsday' obesity crisis. ITV News, January 13 2014

Categories: Medical News

A small amount of coffee will not dehydrate you

Medical News - Fri, 01/10/2014 - 14:00

“Coffee is 'as hydrating' as drinking water,” is the claim in the Daily Express. It reports on a new study suggesting that moderate coffee consumption does not dehydrate the body, as some had previously thought.

The research behind the headline was a small experimental study including 50 healthy male volunteers who were used to drinking three to six cups of coffee a day. On two separate occasions, each man drank either four cups of coffee a day for three days, or drank an equivalent amount of water for three days.

They compared the body’s overall hydration levels using blood samples and looking at urine output. They found no significant difference in measures of hydration between those drinking water and those drinking coffee.

However, there are important limitations to this research. The study participants were a small group of healthy men, all of whom were used to drinking the amount of coffee tested. So they are not necessarily representative of other groups.

In particular, the research may not apply to people who are at risk of dehydration, such as those with diarrhoea and vomiting, or health conditions such as kidney disease. This may also apply to those taking medications that affect their body's ability to regulate fluids.

The study also only looked at the hydrating effects of coffee over a short period (three days) so does not provide information on any longer term effects.

So it cannot be concluded from this study alone that coffee is broadly as hydrating as water. And unlike water, coffee can cause side effects such as insomnia and irritability.

 

Where did the story come from?

The study was carried out by researchers from the School of Sport and Exercise Sciences, University of Birmingham, and was funded by the Institute for Scientific Information on Coffee (ISIC).

The ISIC website describes the organisation as non-profit and devoted to the study and disclosure of science related to coffee and health. Its members are seven major European coffee companies representing a potential conflict of interest. However, the publication states “the funders [ISIC] had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.”

The study was published in the peer reviewed open access medical journal Plos One and can be read online or downloaded for free.

Overall both the Express and the Daily Mail failed to consider the limitations of this research when interpreting the results and considering their implications.

 

What kind of research was this?

This was an experimental study that used a crossover design to directly compare the effects of coffee consumption and water consumption upon hydration in a group of men.

The researchers explain how it is often suggested that coffee causes dehydration and coffee consumption should be avoided or significantly reduced to maintain fluid balance.

They also report that previous research has suggested there is wide variation in the amount of fluid that adults drink each day, ranging from half a litre to over four litres per day.

This suggests there is no clear consensus on the correct amount of fluid to consume. Meanwhile published guidelines are said to vary in recommended fluid intake from 1.5l/day to 3.7l/day in men. The researchers point out that some guidelines say caffeinated beverages should not be included in daily fluid requirement guidelines, and that a glass of water should be consumed with every cup of coffee or tea.

Given the uncertainty around the amount of fluid needed, and whether coffee should be included or excluded, the researchers set out to answer the question of whether coffee did indeed have a dehydrating effect compared to water.

 

What did the research involve?

The study included 50 healthy men (aged 18 to 46) with stable weight, diet and fluid intake, selected from a potential screened group of 100. Women were said to be excluded due to possible fluid balance changes caused by the menstrual cycle. All participants were described as moderate coffee drinkers consuming between three and six cups per day (300 to 600mg/day caffeine) as assessed by a three-day food diary.

Then on two separate occasions, each man drank four, 200ml cups of black coffee per day for three days (providing 4mg/kg of caffeine per day), or three cups of water per day for four days. During each trial period the participants drank a regulated amount of water provided in bottles, the amount of which was determined for each of them based on their three-day food diary. Therefore during the water-only trial, they were drinking four extra cups of water a day. During each trial period the participants also did no physical activity, did not drink alcohol and ate a controlled diet as provided by the researchers. This was to try to limit the effects of these factors on their overall hydration.

The two trial periods were separated by a 10 day wash-out period when the person resumed their normal caffeine intake, diet and activity.

Before and after each trial, the researchers measured total body water. Every day they also recorded body mass and blood and urinary markers of hydration (such as sodium, potassium and creatinine levels). During the coffee trial, blood was also analysed for caffeine levels to confirm compliance.

 

What were the basic results?

The researchers found no significant difference in total body water from before and after each trial. There was also no significant difference in total body weight between the two trials.

Neither were there any differences between the two trials in blood markers or urinary markers of hydration, or 24 hour urine volume.

Urinary sodium levels were found to be higher during the coffee days. The authors say that previous research has suggested that caffeine increases kidney excretion of sodium.

However, the researchers found no difference in other measures of hydration or urine output.

There were no significant differences in body mass between the two trials, though there was a small gradual daily fall in body mass in both trials.

 

How did the researchers interpret the results?

The researchers say their findings of no significant difference in blood and urinary markers of hydration status between trials “suggest that coffee, when consumed in moderation by caffeine habituated males[,] provides similar hydrating qualities to water”.

 

Conclusion

There are several important points to bear in mind when interpreting the meaning of this research:

  • The trial is very small, including a specific group of only 50 healthy men who were all used to drinking three to six cups of coffee per day. In this study, the men drank the same amount of coffee as they were used to drinking. It could be that their bodies have adapted to this level of caffeine over time and it therefore has less effect on hydration. Different findings may be seen in another group of men – particularly those not used to drinking coffee.
  • Different findings could also be seen in women; in children; and perhaps most importantly, in people who are dehydrated or at risk of dehydration (for example with vomiting and diarrhoea), or with certain health problems or taking medications that affect their fluid balance (such as heart or kidney problems).
  • In this group of men they also only tested the effects of drinking four coffees a day for three days, or drinking water only for three days. We don’t know whether continuing with either pattern – water-only drinking, or continued coffee drinking – would have different effects on hydration if measured over the longer term.
  • The study is only measuring blood and urinary measures of hydration but does not examine the other effects of caffeine on the body, for instance, its stimulant properties.
  • This was not a randomised controlled trial. A trial randomising a (preferably larger) group of people to either coffee drinking or water drinking, and examining hydration and other effects on the body over a longer period of time, would give a more reliable indication of the effects.

Coffee contains caffeine, which is known to be a diuretic. As many people who drink several cups of coffee will know, it makes you pass urine. Also, as many people may have noticed themselves, when feeling particularly thirsty, a glass of water is more likely to quench your thirst than a cup of coffee.

Taking all of these things into account, it cannot be concluded from this study alone that coffee is as hydrating as water as the news headlines state.

If you are in good health then a moderate amount of coffee is not going to cause you any problems. But it is not recommended as your sole source of hydration as caffeine, unlike water, can cause side effects.

For example, a study we discussed in 2013 found that people who drank coffee during the afternoon had impaired sleep quality compared to those who went caffeine-free.

 

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter.

Links To The Headlines

Coffee is 'as hydrating' as drinking water. Daily Express, January 10 2014

Coffee doesn’t dehydrate us: A few cups a day are 'as hydrating as water'. Daily Mail, January 10 2014

Links To Science

Killer SC, Blannin AK,  Jeukendrup AE. No Evidence of Dehydration with Moderate Daily Coffee Intake: A Counterbalanced Cross-Over Study in a Free-Living Population. PLoS One. Published online January 9 2014

Categories: Medical News

US recession saw more Google stress searches

Medical News - Fri, 01/10/2014 - 03:00

"Google searches for stress-related illnesses rose during the recession," the Mail Online reports. The news comes from research looking at how US Google search trends for health complaints changed during the period researchers dubbed the "Great Recession".

The recession, which affected most western countries, was sparked by a global banking crisis and lasted from 2008 to 2011, although many would argue we are still suffering from its effects today.

Researchers found that higher than expected numbers of Google searches for illnesses that may sometimes be associated with stress, such as headaches and stomach ulcers, occurred during this time.

This is an interesting approach and adds to the body of evidence suggesting that Google search data can be used to gain an insight into wider health trends. For example, researchers can use Google to map flu prevalence based on search activity.

However, the study has a number of limitations, including the fact that searching for a health condition does not necessarily mean that the person was experiencing the problem themselves. It is also possible that the effect of increased internet usage with time in general has not been fully accounted for.

We do not know whether Google searches in the UK would show the same pattern. However, some of the most searched for conditions between 2008 and 2011 on the NHS Choices website were conditions that may in part be influenced by stress, such as depression and back pain.

If money – or, more specifically, the lack of it – is causing you stress, there are a number of organisations that can help.

 

Where did the story come from?

The study was carried out by researchers at the Santa Fe Institute, the University of Southern California and other US institutions, and was funded by a Google.org grant, a National Science Foundation (NSF) Graduate Research Fellowship and the Omidyar Foundation.

It was published in the peer-reviewed American Journal of Preventive Medicine and is free to read online or download (PDF, 834kb) as a PDF on an open access basis.

The Mail Online's reporting fails to note there are many limitations in the approach this study used that may affect the interpretation of the results. They also do not note that this study relates to Google searches in the US during the recession, not in the UK.

 

What kind of research was this?

This research examined Google search queries to see how specific health concerns changed during the US recession between 2008 and 2011.

The authors say that most previous research examining the health effects of the economic situation comes from surveys. Surveys can provide useful data, but they are cost intensive and time consuming to complete. They also often include non-specific measures, such as general self-ratings of health, rather than looking at specific concerns.

The researchers say that by monitoring hundreds of systematically selected Google query trends, their novel approach "takes the traditional self-rated health questionnaire to the next level by identifying precise health concerns by the query content and their prevalence by the query volume".

This is arguably an appropriate approach to take because of the sheer pervasiveness of Google. It is estimated that more than one billion Google searches occur in the course of just one day.

 

What did the research involve?

Search trends in the US were downloaded from Google Trends in the form of weekly relative search volume (RSV) time series.

These automatically generated search figures reflect the proportion of search queries inputted by the investigator (the person Googling) relative to all queries each week, normalised on a 100-point scale.

For example, an RSV of 50 means 50% of the search volume of the highest search proportion in that week. This is said to correct for overall increases in Google searches over time as a result of changes in internet access or people's disposable time.

The researchers focused on health concerns that previous research has suggested may have both a psychosomatic element and be caused by economic concerns. These included complaints such as chest pain, headache and other pain, and stomach problems.

The researchers used the term "Great Recession" to describe the period between December 2008 and 2011. They then compared the cumulative difference between the observed and expected search query volume based on linear projections from pre-existing trends.

Higher than expected searches during the recession years were called "excess" searches. The 100 queries with the greatest excess searches were ranked and clustered into themes based on search query content.

 

What were the basic results?

Overall trends showed that compared with the period 2006-08, there was a general 26% increase in searches for all health concerns during the Great Recession.

Among the top 100 health concerns, there were around 205 million excess health concern queries during the Great Recession. These were considered "excess" in the sense that they were higher in number than would be expected if previous pre-recession trends had continued.

The specific concerns with the greatest excess queries were stomach ulcer symptoms, with a 228% increase above expected, accounting for around 1,480,000 excess queries. Headache symptoms had a 193% increase above expected, accounting for around 1,520,000 excess queries. 

Queries tended to follow themes of looking for symptoms and diagnostic procedures or tests, such as heart monitor tests. Other top concerns were hernia (37% above expected), chest pain (35%) and heart rhythm problems (32%).

Other types of pain with excess queries were back, stomach and tooth pain (each with 19% excess), and joint pain (11% excess).

Cancer searches were also up by 32% during the period, with "congestion" (breathing problems) searches up by 26% and pregnancy searches up by 22%.

The confidence intervals on the estimates of the excess searches were noticeably large, indicating there is a large margin of error in the estimates given above.

For example, all health-related search queries were estimated to have an excess of 26% overall, but the true value was reported to be anywhere between 3% and 138%, as expressed using a 95% confidence interval.

 

How did the researchers interpret the results?

The researchers conclude that, "Google queries indicate that the Great Recession coincided with substantial increases in health concerns, hinting at how population health specifically changed during that time."

 

Conclusion

This research found that there were increased Google searches during the US "Great Recession" between December 2008 and 2011 for a range of health concerns, including headaches, stomach ulcers and other stomach problems, chest pain, heart rhythm problems and various other pains, including back pain and toothache. The researchers consider that this could potentially indicate worsening population health.

However, although this is an interesting approach, it is limited by several factors. A person may search Google for information on a health complaint for many different reasons. It does not necessarily mean that a person was experiencing that problem themselves.

Even if they were experiencing the general symptom searched for, it cannot tell us what their actual diagnosis was, how long they had been suffering from it, or any associated health problems they had. It certainly cannot tell us what the direct cause was.

It is worth pointing out that not everyone with a health problem chooses to search for information about it on Google as a first port of call. Many people may just visit a doctor and obtain related health information through other sources, such as printed literature or media sources other than Google.

Although the research has tried to account for increases in overall internet usage with time, including improved internet access or more disposable time, it is still difficult to tell whether this effect has been completely accounted for.

This research also only relates to searches in the US and did not investigate whether Google searches in the UK showed the same pattern.

However, the study highlights how Google search data could be used to provide a useful insight into wider health trends at a population level.

Bearing the limitations in mind, the suggestion that economic problems can trigger health problems is certainly plausible, although it cannot be proven by this research.

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter.

Links To The Headlines

Did the recession make us physically ill? Google searches for abdominal pain and headaches rose during economic downturn. Mail Online, January 9 2014 

Links To Science

Althouse BM, Allem J, Childers MA, et al. Population Health Concerns During the United States' Great Recession (PDF, 834kb). American Journal of Preventive Medicine. Published online January 7 2014

Categories: Medical News

Medical 'superglue' shows promise for heart surgery

Medical News - Thu, 01/09/2014 - 03:00

"A medical superglue has been developed that has the potential to patch heart defects on the operating table," BBC News reports. The glue has currently only be used in animals, but the results are encouraging.

Medical glue is currently used to close minor skin wounds in some operations, but its use has been limited for several reasons – it can be activated by contact with blood before it reaches its intended position, for example, and is also water soluble, so it can be washed away.

This study used a newly developed type of glue that is thick and sticky until it is activated by ultraviolet (UV) light. In the experiments, it was used to:

  • attach a patch to the septum (the part separating the left and right chambers of the heart) of pigs' hearts while they were still beating
  • apply a patch to a hole in the hearts of several rats
  • repair a small cut in a pig's artery and withstand pressures higher than normal blood pressure

On the whole, these experiments were successful, but the animals were only monitored for a short period of time after surgery.

This research has great potential for the future, but longer term studies are required to assess for complications or any toxic effects before human experiments will be possible.

If experiments prove successful, this superglue could revolutionise surgery for cases where surgeons need to repair the damage resulting from a heart attack, or in the treatment of children born with a defective heart (congenital heart disease).

 

Where did the story come from?

The study was carried out by researchers from Boston Children's Hospital, Harvard Medical School, Brigham and Women's Hospital and the Massachusetts Institute of Technology in the US, the University of Coimbra in Portugal, and the Department of Pediatric Cardiology in Bolivia.

It was funded by the Center for Integration of Medicine and Innovative Technology, Boston Children's hospital and the National Institutes of Health in the US, the Portuguese Foundation for Science and Technology, and the German Research Foundation.

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

The study was accurately reported by BBC News.

 

What kind of research was this?

This was a laboratory study investigating a new technology carried out in animals. The researchers aimed to create a type of glue that would be strong enough to attach tissues or other materials together during surgery on areas of high blood flow.

Usually, during surgery tissues are held together with stitches or staples, but this can cause damage to the tissues, is time consuming and does not make a watertight seal.

Existing medical glues are not strong enough to use in challenging situations, for example where there is high blood flow or if the tissue is moving (contracting), such as in the heart.

There have also been other limitations, such as the glue being activated by contact with blood before it reaches the intended position, medics not being able to reposition the glue, and the fact that the glue is water soluble and can therefore be washed away. A further limitation of the glue being water soluble is that it can swell up and tear.

The researchers were inspired by the ability of slugs and sandcastle worms, a type of worm found in California known to produce a strong "underwater" glue. These creatures can produce viscous (thick and sticky) secretions that are not easily washed away and do not mix with water.

They wanted to develop a glue that would imitate natural substances, be stable, not dissolve in water, be activated by light once in the right place, and be able to achieve a flexible watertight bond.

 

What did the research involve?

A compound (mixture) of two naturally occurring substances – glycerol and sebacic acid – was developed, which the researchers dubbed hydrophobic (insoluble) light-activated adhesive (HLAA). The mixture is very viscous and easy to spread over a surface. When activated by ultraviolet (UV) light, it becomes a strong, flexible adhesive.

To get the strongest glue, the researchers experimented with:

  • different amounts of glycerol and sebacic acid
  • light intensity
  • length of time the light was used

HLAA was used in operations on small and large animals that would be similar to human operations, including the repair of cuts to blood vessels and closing holes in the wall of the heart.

Researchers performed a series of experiments:

  • they compared patches covered in HLAA with current medical glue by sticking them to the outside of rats' hearts
  • they compared HLAA to conventional stitches by making a hole in the heart of two groups of rats, and used the HLAA patches to close it in one group (n=19) and compared this to using stitches in the other (n=15)
  • they put patches coated with HLAA on the septum of four pigs' hearts
  • they glued a small cut measuring 3-4mm to a pig artery in the laboratory using HLAA and then assessed at what pressures it would remain closed to see if it could cope with human blood pressures

 

What were the basic results?

The research found that HLAA was 50% as strong as the medical glue currently in use. However, when the researchers put the glue onto patches, they were able to put it into position without the glue being washed off. They were then able to fix it with UV light.

When the same technique was performed using the current type of glue, it was immediately activated when it came into contact with the blood and was therefore harder to use.

Patches covered with HLAA were stuck to the outer layer of the hearts of rats and could be repositioned before sticking with the UV light, whereas the patches using current medical glue could not. After seven days, all of the patches were attached in both groups (n=3).

The researchers performed the same operation and monitored the rats for 14 days (HLAA n=5 and current medical glue n=4). The degree of tissue death and inflammation was significantly less in the HLAA group. There was no difference between the groups for heart function.

For the heart wall defects, successful closure was achieved with HLAA patches in 17 of the 19 rats, but one died from bleeding complications four days later. The 6mm diameter patch did not cover the 2mm hole in three of the rats.

As the researchers point out, rats' hearts beat six to seven times faster than human hearts, so they do not think this would be as difficult to achieve in humans.

Successful closure with stitches was achieved in 14 out of 15 rats. There was no significant difference between the groups after 28 days, although all had reduced heart function in the area of the repair.

The patch to the pigs' septum stayed in place until the pigs were put down 4 or 24 hours after the surgery.

Applying the glue without a patch to cuts of 3-4mm in pig arteries created a seal that was able to stay together withstanding pressures of up to 203.5mmHg, ± 28.5mmHg.

This is impressive, as the systolic pressure (the level of blood pressure as the heart beats out) of human arteries is usually around 120mmHg.

 

How did the researchers interpret the results?

The researchers reported that the HLAA "achieves a strong level of adhesion to wet tissue and is not compromised by pre-exposure to blood ... it could be used for many cardiovascular and surgical applications".

They also acknowledge that, "For translation into humans, additional safety and toxicity studies may be required".

 

Conclusion

This innovative glue has shown promise during animal experiments involving rats and pigs. The consistency and technique of "fixing" the glue appears to show some advantages for new surgical techniques, but there are some limitations that need to be addressed before it can be tested in humans.

The researchers mention that the "rapid curing" (the light treatment process) helped avoid exposure to high temperatures, but it is not clear what effect the UV light may have on surrounding tissues. The animals were also only followed up for a short period of time after the surgery. It would be important to find out if there are any longer term side effects of using this technique.

This research has great potential for the future, but longer term studies will be required to assess for complications and any toxic effects before human experiments will be possible. 

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter.

Links To The Headlines

Medical glue 'can fix broken heart'. BBC News, January 8 2014

Links To Science

Lang N, Pereira MJ, Lee Y, et al. A Blood-Resistant Surgical Glue for Minimally Invasive Repair of Vessels and Heart Defects. Science Translational Medicine. Published online January 8 2014

Categories: Medical News

Risks of infertility treatments 'overhyped'

Medical News - Thu, 01/09/2014 - 03:00

“IVF births carry five times risk of complications,” the Daily Mail reports.

While this headline is essentially true, it is a classic example of a “relative risk” which sounds frightening out of context. In this case, the headline ignores the fact that the number of serious complications found, such as stillbirth and neonatal death was very small.

The story comes from a large study in Australia looking at health outcomes for babies born after fertility treatments (not just IVF), compared with those born after “spontaneous conception”.

Overall, it found that the risk of the following serious complications is around twice as high for babies born after fertility treatment, but the risk is still relatively low:

  • the rate of stillbirth was 1.1% for any assisted conception compared to 0.5% for spontaneous conception 
  • the rate of premature birth was 7.9% compared to 4.7%
  • low birth weight 9.4% compared to  4.7%and
  • neonatal death 0.5% compared to 0.3%

The risk of complications varied according to the method of treatment used, with problems more common in births from conventional IVF (in which sperm are positioned close to an egg, in the laboratory) than from a method called Intracytoplasmic sperm injection (ICSI), in which a single sperm is injected into an egg.

When frozen embryos were used, the higher risk of complications associated with ICSI (but not with standard IVF) were eliminated.

The study also found that babies born to women who had previous fertility problems but no recorded treatment, had the highest risk of complications.

However, the cause of this higher risk is uncertain. It is possible that many of the complications were due to underlying medical problems associated with infertility, rather than the infertility treatment itself.

 

Where did the story come from?

The study was carried out by researchers from the University of Melbourne and the University of Adelaide in Australia, and was funded by the National Health and Medical Research Council and the Australian Research Council.

The study was published in the peer-reviewed journal PLoS One. PLoS One is an open access journal so the study is free to read online or download as a PDF.

The Daily Mail’s headline was somewhat alarmist and would have better served readers by placing the increase in risk in its proper context. A five-fold increase in a very small risk for serious complications such as still birth is still, essentially, a small risk. However, the paper did include comments from independent UK experts who put the risk in an appropriate context later in their article.

The Guardian carried an accurate and detailed report of the topic.

 

What kind of research was this?

This was an analysis of the outcomes of more than 300,000 births in South Australia over a 17-year period, including 4,300 births from assisted reproduction.

Researchers compared adverse birth events including stillbirths, premature birth, low birthweight and neonatal death (in which the baby dies within weeks of birth), after spontaneous conception and after fertility treatment.

All available fertility treatments were studied including IVF, ICSI, ovulation induction by drugs, and freezing of embryos.

The researchers make the case that this is the first large scale study to examine the association between different fertility treatments and other complications.

They also analysed outcomes for both single and twin births, excluding higher multiple births (triplets or more).

 

What did the research involve?

The researchers created a database linking all patients in the state of South Australia who received fertility treatment between January 1986 and December 2002 with the state’s records of all live births and stillbirths in the same period.

Over 20,000 births were excluded from the research. Most of these were pregnancies among mothers under 20 years of age (as only two of these pregnancies were conceived with infertility treatment). Triplet and quadruplet births were also excluded, as were births of babies of indeterminate or unknown sex.

The resulting database included information on 327,378 registered births, 321,210 of which followed a natural conception.

The spontaneous conception group were further classified into: 

  • births to women with no recorded history of infertility in their records and no infertility treatment
  • births to women who had a recorded diagnosis of infertility but no associated specialist treatment
  • births as a result of spontaneous conception in women with a previous birth from fertility treatment

They looked at the following types of fertility treatments:

  • egg donation
  • gamete intrafallopian transfer (GIFT), where eggs and sperm are placed in the fallopian tubes
  • intrauterine insemination (IUI), where healthy sperm are placed in the woman’s womb
  • IVF with fresh embryos
  • IVF with frozen embryos
  • ICSI with fresh embryos
  • ICSI with frozen embryos
  • minimal medical intervention and ovulation induction (OI) only (ovulation is stimulated using drugs, such as clomiphene citrate)

They analysed and compared the following birth outcomes:

  • stillbirth
  • birth weight
  • low birthweight
  • very low birthweight
  • premature birth (before 37 weeks gestation)
  • very premature birth (before 32 weeks gestation)
  • late (post-term) birth (after 41 weeks gestation)
  • small size for gestational age
  • very small size for gestational age
  • large size for gestational age
  • apgar score (this is a quick test of the baby’s health carried out in the minutes after birth)
  • neonatal death (within a few weeks of birth)

Analyses of birth outcomes other than stillbirth were restricted to live born single babies (296,401) and twins (8,824).

They adjusted all their results for factors which might influence outcomes (confounders) such as maternal age, number of previous births and sex of the baby.

 

What were the basic results?

The researchers found that compared to birth after spontaneous conceptions, single babies born after assisted conception were more likely to be stillborn (odds ratio (OR) 1.82, 95% confidence interval (CI) 1.34 to 2.48).

Of the babies who survived, those born after assisted conception were more likely to:

  • be lower birth weight (mean -109g, CI -129 to -89) and very low birth weight (OR = 2.74, CI 2.19 to 3.43)
  • be very premature (OR = 2.30, CI 1.82 to 2.90)
  • die in the days after birth (OR = 2.04, CI 1.27 to 3.26)

 The outcomes varied by the type of fertility treatment couples had:

  • Very low and low birth weight, very preterm and preterm birth, and neonatal death were markedly more common in singleton births from IVF and to a lesser degree, in births from ICSI.
  • When using frozen embryos, all significant adverse outcomes associated with ICSI (but not with IVF) were eliminated.
  • Frozen embryo cycles were also associated with increased risk of macrosomia (excess birth weight) for IVF and ICSI singletons (OR = 1.36, CI 1.02 to 1.82; OR = 1.55, CI 1.05 to 2.28).
  • In couples with a history of infertility but no treatment who eventually conceived, babies were nine times more likely to have a very low birthweight, seven times more likely to be very premature and almost seven times more likely to die within the first 28 days of birth.

The study also found that compared to babies conceived naturally:

  • Babies born after egg donation were at increased risk of being born low or very low birthweight, or be very premature.
  • Babies born after artificial insemination were lighter at birth and more likely to be low or very low birthweight or very small size for gestational age.
  • Using drugs to induce ovulation was associated with an increased risk of low birthweight and late birth.

 

What were the researchers’ conclusions?

The researchers conclude that births after assisted conception show “an extensive range of compromised outcomes” that vary according to the type of fertility treatment used. In some types of treatment, the risk was substantially lower when frozen embryos were used, but this is also associated with an increased risk of excess birth weight.

They suggest that embryo freezing may have a “selective effect” with more compromised embryos less likely to survive.

They also suggest that high rates of birth complications among women previously untreated for fertility problems may be associated with the “poorly supervised” use of fertility drug clomiphene citrate. This group of births should be studied further, they argue.

Further research is needed they argue to pinpoint the cause of the higher risks of birth complications associated with fertility treatment. Routine monitoring of couples undergoing such treatment is also recommended.

 

Conclusion

The study raises concerns about the link between different types of fertility treatment and poorer outcomes at birth. However, it is uncertain whether the higher risk is down to infertility treatment, underlying health problems associated with infertility, or a combination of both. As the authors point out, the study did not control for the underlying cause of fertility problems.

Although the risks appear higher, the overall risk of these problems is still low. And although the study excluded multiple births, it had no information on whether the single babies born after fertility treatment were the result of multiple pregnancies, a known risk factor for adverse outcomes at birth.

As the authors point out, data for assisted conception pregnancies was not available beyond 2002, and improvements in pregnancy outcomes after assisted reproduction have been noted in recent years.

The findings of the study would have been more useful if information on the underlying causes of fertility problems had been gathered, as these may have had a significant effect on outcomes.

This study reinforces the importance of careful monitoring of women undergoing fertility treatments – and it is unclear how the Australian health system compares with UK NHS or private fertility treatment. 

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter.

Links To The Headlines

IVF births carry five times the risk of complications: Babies born thanks to fertility treatment more likely to be stillborn, premature or die after a few weeks. Daily Mail, January 9 2014

IVF babies have greater risk of complications, study finds. The Guardian, January 8 2014

Links To Science

Marino JL, Moore VM, Wilson KJ, et al. Perinatal Outcomes by Mode of Assisted Conception and Sub-Fertility in an Australian Data Linkage Cohort. PLoS One. Published online January 8 2014

Categories: Medical News

'Piggy-backing proteins' could kill cancer cells

Medical News - Wed, 01/08/2014 - 14:00

“Cancer-killing "sticky balls" can destroy tumour cells in the blood and may prevent cancers spreading,” BBC News reports.

The headlines follow a laboratory study which found that “piggy-backing” two proteins to white blood cells caused cancer cells to die.

Cancer can spread in three ways; directly, via the lymphatic system, and through the blood. The latter is particularly dangerous, as if cancer spreads through the blood it can spread from one part of the body to others, such as from the lungs and into the brain (this is known as metastasis).

Metastatic cancer is responsible for 90% of cancer-related deaths, and currently, we have only limited ways to stop the spread of blood-borne cancer cells.

This study made use of two proteins normally found on the surface of a type of white blood cell called “natural killer cells” which kill abnormal and infected cells. In the laboratory, these two proteins were mixed with human blood and stuck to other types of white blood cells that could target cancerous cells.

These “retrofitted” white blood cells were then injected into mice that had been exposed to the type of abnormal cells associated with colon and prostate cancer in humans.

Encouragingly, a significant number of the cancer cells died.

While this is an exciting new avenue of animal research, there are many more steps to take before such a treatment could be used to prevent the spread of tumours in cancer patients.

 

Where did the story come from?

The study was carried out by researchers from Cornell University and was funded by the Cornell Centre on the Microenvironment and the National Cancer Institute.

The study was published in the peer-reviewed medical journal Proceedings of the National Academy of Sciences (PNAS) of the United States of America. The study has been published on an open access basis so it is free to read online or download as a PDF.

Generally the media reported the story accurately, though The Daily Telegraph was over-optimistic that the method could “prevent 90 per cent of deaths”. This is the estimated number of cancer deaths due to metastasis, but even if this new technique could reduce the spread of cancer in the blood stream, many cancers are first diagnosed at a late stage, after they have metastasised.

 

What kind of research was this?

This was a laboratory study that looked at the effect on cancer cells of white blood cells with two proteins attached to their surface. The researchers aimed to see how many cancer cells were affected by using both human blood samples, and live mice. This was an early stage study in the long process of developing new treatments for cancer.

 

What did the research involve?

The researchers initially mixed cancer cells in a solution with two different proteins that are usually present on a certain type of white blood cell called “natural killer cells”.

These cells are part of the immune system, and as their name implies, they have a role in killing abnormal and infected cells.

The two proteins normally found on natural killer cells are called TNF-related apoptosis inducing ligand (TRAIL), and E-selectin adhesion receptor (ES). The researchers found that cancer cells were more likely to die if they were exposed to both proteins at once.

The researchers then added both proteins (ES/TRAIL) to human blood samples and found that they stuck to the surface of other types of white blood cells. They called these “unnatural killer cells”.

Still in the laboratory, they mixed colorectal cancer cells and prostate cancer cells into the blood under “flow” conditions so that the cells would bump into each other, mimicking blood circulation.

The researchers then injected colorectal cancer cells into the blood circulation of mice. After 30 minutes they injected either ES/TRAIL, ES or TRAIL. They measured the number of cancer cells left after two and a half hours, and looked at how many cancer cells had been deposited in the lungs.

 

What were the basic results?

In a human blood sample in the laboratory:

  • less than 5% of the cancer cells remained after ES/TRAIL treatment
  • the rate of cancer cell death was much higher than when cancer cells were just mixed with the proteins without the blood
  • adding ES/TRAIL proteins to the surface of white blood cells did not cause the white blood cells to die over 24 hours 
  • ES/TRAIL proteins did not have an effect on the lining of blood vessels

In mice:

  • after two and a half hours, mice injected with ES/TRAIL had less than 2,000 cancer cells per ml of blood compared to mice injected with just ES, who had roughly 130,000 cancer cells per ml of blood
  • half as many cancer cells were found in the lungs of the mice treated with ES/TRAIL
  • ES/TRAIL proteins attached to the surface of white blood cells without causing any obvious problems

 

How did the researchers interpret the results?

The researchers concluded that this study “represents an important first step toward the targeting of circulating tumour cells in the bloodstream as a means to prevent cancer metastasis. Clinically, for instance, one could envision using these liposomes as a preventive measure upon diagnosis of highly metastatic hematogenous cancers [those with a high propensity to spread via the bloodstream] such as those originating in breast, prostate and lung”.

 

Conclusion

This laboratory study has shown that white blood cells do not seem to be harmed when two proteins usually found on the surface of a particular immune cell with a role in killing abnormal cells are attached. Encouragingly, it showed that doing this can cause cancer cells to die in human blood samples. Similar results were found when these two proteins and cancer cells were injected into the blood circulation of live mice.

These are exciting early results suggesting these proteins could have the potential to be developed into a trial treatment that may be able to prevent cancer cells spreading via the bloodstream. However, much further research will be needed to determine the risks and harms of such an approach before any testing can be conducted in humans.

The media suggests that such a treatment could “prevent 90 per cent of deaths”. This figure is the estimated number of cancer deaths that are due to metastasis. However, even if this new technique could reduce the spread of cancer in the bloodstream, many cancers are first diagnosed at a late stage, after they have metastasised.

Overall, it is far too early to suggest that this treatment could save the lives of people who would otherwise die as a result of cancer spread to other organs of the body (metastases).

With these caveats in mind this is genuinely exciting research. While there is currently no guarantee that it will lead to effective treatments in humans, novel approaches that could be used to combat cancer are always welcome.

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter.

Links To The Headlines

'Sticky balls' may stop cancer spreading. BBC News, January 7 2014

Cancer cells can be killed in blood before reaching healthy organs. The Daily Telegraph, January 7 2014

Links To Science

Mitchell MJ, Wayne E, Rana K, et al. TRAIL-coated leukocytes that kill cancer cells in the circulation. PNAS. Published online January 6 2014

Categories: Medical News

Spoon-feeding link to child obesity 'not proven'

Medical News - Wed, 01/08/2014 - 13:30

"Spoon-fed babies more likely to be overweight," reports The Independent. The study the news comes from found an association between feeding techniques and weight gain, although many other factors may also be involved.

The study looked at whether the way mothers introduced solid foods to their babies (weaning) was linked to the child's weight and their "eating style" as a toddler. Researchers looked at two methods of weaning: "traditional" spoon-feeding and what is termed baby-led weaning (BLW), where babies pick up food and feed themselves.

The study found that the BLW babies were less likely to be overweight when assessed between the ages of 18 and 24 months. However, babies in both groups were predominantly of a normal weight.

The researchers speculate that the BLW approach may lead to better appetite control in later life, but this speculation remains entirely hypothetical. However, they did find a bigger "satiety response" in the BLW group, which is the child's ability to regulate what they eat when they feel full.

The study does not show that spoon-feeding causes obesity. It has several limitations, including the fact that it is based on mothers self-reporting, which might affect its reliability. A longer follow-up period would also be useful, as it is currently unclear whether toddlers who were overweight would stay that way in the future.

Still, parental approaches to feeding are an important area of research. Experts agree that a relaxed attitude to feeding and allowing babies to explore food is best for the child, although this is often easier said than done.

 

Where did the story come from?

The study was carried out by researchers from Swansea University. There is no information about external funding. It was published in the peer-reviewed journal Pediatric Obesity.

This study was covered rather too uncritically in both The Independent and the Daily Mail.

The Independent reports on the study as if the researchers' hypothesis that baby-led weaning leads to better appetite control in later life is a proven fact. This is certainly not the case.

 

What kind of research was this?

This was a cohort study looking at whether the way babies were weaned was linked to their eating behaviour and weight at 18-24 months.

This type of study is often used to examine whether certain lifestyle factors are linked to later health outcomes, but it cannot prove cause and effect.

It is always possible that other factors (confounders) may influence the results of a cohort study, although researchers usually try to take these factors into account.

A lot of supportive evidence is needed before we can be reasonably certain that a lifestyle habit or exposure directly causes a health outcome. Ideally, as the researchers point out, a randomised controlled trial would be carried out.

The researchers say it is important to understand the role of the early feeding environment in determining the risk of obesity. For example, a "controlling parental child feeding style" has been associated with poorer appetite regulation in previous studies, such as a BMJ study covered by Behind the Headlines in 2012.

The researchers point out that traditionally infants are weaned with puréed foods, which tend to be spoon-fed by a parent or carer, alongside a gradual introduction to finger foods (standard weaning, or SW).

However, baby-led weaning (BLW) is a recent popular trend that emphasizes self-feeding by infants from the age of six months. This means foods are presented to the baby in their whole form and the baby decides which food item to select, how much to eat and how quickly to eat it.

The researchers set out to examine whether infants weaned using a baby-led approach exhibited differences in eating behaviour during their second year, compared with those weaned using a standard approach. The study also explored the role of maternal control, breastfeeding duration and the timing of the introduction of solid foods.

This is the second phase of a two-part study. The researchers say that in phase one, they showed that a BLW style was associated with "significantly lower levels of control" compared with standard weaning.

 

What did the research involve?

In phase one of the study, 604 mothers with an infant aged 6-12 months who had started consuming solid foods completed a questionnaire examining their weaning style.

The mothers were recruited through mother and baby groups in Wales as well as online parenting forums. They were classed as either baby-led or standard weaners:

  • mothers were classed as baby-led weaners (BLW) if they reported using both spoon-feeding and purées 10% of the time or less
  • mothers who reported using both spoon-feeding and purées more than 10% of the time were classified as standard weaners (SW)

The mothers also completed a standard child feeding questionnaire on breastfeeding duration and the timing of introduction to solid foods.

They were invited to take part in phase two of the study when their children were aged between 18 and 24 months. Three hundred and twenty five mothers responded to the invitation. After exclusion criteria such as child health problems or an incomplete survey were applied, 298 mothers – just under half the original sample – remained in the study.

These mothers completed a second child feeding questionnaire, answering questions about pressure to eat, monitoring, concern for child weight and perceived responsibility.

In particular, they were asked about:

  • food responsiveness – desire of the child to eat in response to food stimuli, regardless of how hungry they are
  • enjoyment of food – a positive eating style and enjoyment of eating
  • satiety responsiveness – the child's ability to regulate intake of food in relation to feelings of fullness
  • slowness in eating – the speed at which a child eats 
  • food fussiness – where a child is "picky" and has limited food choices in terms of the range she or he will eat

Participants also self-reported the current weight of their child. This was classified by researchers as normal, underweight or overweight or obese according to standard international child growth charts.

Researchers analysed the data using standard statistical methods.

 

What were the basic results?

The researchers found that, overall, mothers reported that infants weaned using BLW were significantly more responsive to feelings of fullness and were less likely to be overweight compared with those weaned using a standard approach. 

They also found that infants in both groups were predominantly a normal weight, with 11.7% overweight and 3.7% underweight.

The results were independent of breastfeeding duration, timing of introduction to solid foods, and maternal control (that is, how often the mother allowed the child to eat over the course of a day).

 

How did the researchers interpret the results?

The researchers conclude that a baby-led weaning approach may encourage greater responsiveness to signals of fullness and healthy weight gain trajectories in infants. 

They say that mothers who used BLW had children who were perceived at follow-up as having better appetite control and lower BMI than children weaned using spoon-feeding.

 

Conclusion

As the authors point out, this study has several limitations that might have influenced the results:

  • The sample of mothers used was self-selected, so a mother choosing to take part in such a study may not be representative of the wider population.
  • The results were based on mothers self-reporting, including an estimate of the infants' weight.
  • Results might have been influenced by parental attitudes, rather than the method of feeding. For example, it is possible that parents who adopted the BLW approach strongly believed in it, which may in turn have influenced the way they completed the questionnaire.
  • The results may also have been influenced by infant attitudes. For example, parents of infants who were more responsive to food and less fussy to begin with may have been more inclined to follow BLW.
  • Many confounders might have influenced the results, including maternal education and income and the duration of breastfeeding. However, researchers did adjust their results for some of these.
  • There is no formal definition of BLW and the classification used by researchers to divide mothers between BLW and SW was odd. For example, mothers were defined as SW who may only have been spoon-feeding a minority of the time.

Many parents follow a mix of allowing infants to explore food and helping him or her along the way with some spoon-feeding. It is generally accepted that a relaxed attitude to feeding is best for the child, although this is often easier said than done.

Ultimately, it is what, rather than how, your child eats that is going to have the most significant long-term influence on their future weight. Just like adults, children benefit from a balanced low-fat diet that contains at least five portions of fruit and vegetables a day. You should also limit their consumption of sugar and salt.

Read more about child health.

Analysis by Bazian. Edited by
NHS Choices. Follow Behind the Headlines on Twitter.

Links To The Headlines

Spoon-fed babies more likely to be overweight. The Independent, January 7 2014

Spoon-fed babies are 'more likely to become obese' because their bodies don't recognise when they are full. Daily Mail, January 7 2014

Links To Science

Brown A, Lee MD. Early influences on child satiety-responsiveness: the role of weaning style. Pediatric Obesity. Published online December 17 2013 

Categories: Medical News

Does a high-fibre diet help relieve asthma?

Medical News - Tue, 01/07/2014 - 13:00

"Eating more fibre could help treat symptoms of asthma, scientists say," The Independent reports. This headline is based on a mouse study that looked at the role that different types of dietary fibre play in the gut and its effect on allergic airway inflammation.

Allergic airway inflammation – which happens in conditions such as asthma – is where the immune system mistakes harmless triggers such as dust mites as a threat. This causes the airways to become inflamed, leading to symptoms such as wheezing and breathlessness.

Allergic asthma cases are increasing in developed countries, which are also seeing fewer people eating a high-fibre diet. The researchers wanted to see if there could be a possible association between the two.

To do this, they carried out a series of laboratory and animal experiments on mice and found that mice given diets high in soluble fibre (a human equivalent would be fruit and vegetables) had more of a protective effect on lung inflammation compared with mice given different types of fibre.

It's important not to interpret the findings as being definitely applicable to people, but they are a good starting point for further study in humans.

Eating a high-fibre diet is recommended, even if it turns out to be an ineffective way of preventing asthma. It may help prevent heart disease, diabetes, weight gain and some cancers, and can also improve digestive health. Read more about why fibre is important.

 

Where did the story come from?

The study was carried out by researchers from the University of Lausanne in Switzerland and was funded by a grant from the Swiss National Science Foundation. It was published in the peer-reviewed journal Nature Medicine.

This study was covered appropriately by the UK media, although some of the headlines implied that the study was conducted in humans, which is not the case.

 

What kind of research was this?

This was laboratory and animal research looking at what role dietary fibre plays in the gut and influencing lung inflammation in mice.

Fibre is only found in foods that come from plants. There are two different types of fibre – soluble and insoluble. Soluble fibre can be digested by your body and is found in fruit and vegetables, oats and golden linseeds.

Soluble forms of fibre can "ferment" in the gut and be converted to short-chain fatty acids. These are often termed essential fatty acids as they cannot be manufactured by the body, but are essential building blocks for long-chain fatty acids. These have a variety of roles, including in neurological function and immunity.

Insoluble fibre can't be digested by your body. It passes through your gut without being broken down and helps other foods move through your digestive system more easily. Examples of foods that are sources of insoluble fibre include wholemeal bread, cereals and nuts.

 

What did the research involve?

The research involved a series of animal and laboratory experiments. In one of the experiments, a group of mice were fed either a normal-fibre diet or a low-fibre diet. All of the mice were then exposed to house dust mites (a common trigger for asthma symptoms in humans) and were monitored for up to six days to see if there was any allergic airway inflammation.

Another experiment was performed on a second group of mice where increased amounts of fibre were given. Mice were either given the normal-fibre diet plus cellulose (a poorly fermentable fibre – this served as a control) or a normal-fibre diet plus pectin (readily fermentable fibre), and all underwent the same monitoring for airway inflammation.

The researchers then analysed the effect of dietary changes on the microbial population (levels of micro-organisms such as bacteria) of the gut and lung tissue of the mice, among other various experiments.

 

What were the basic results?

The main results of the study were:

  • Mice given a low-fibre diet had stronger allergic reactions to house dust mite than mice fed a normal-fibre diet.
  • Mice fed a pectin-rich diet (readily fermentable fibre) had more of a protective effect on lung inflammation compared with mice fed a poorly fermentable fibre diet.
  • Dietary fermentable fibre changed the composition of the gut and lung microbiota (the types of species making up the population of bacteria) of mice. The gut microbiota metabolised the fibre and increased the concentration of short-chain fatty acids, which may promote better health.
  • Mice fed a high-fibre diet had increased circulating levels of short-chain fatty acids and were protected against allergic inflammation in the lung compared with mice fed a low-fibre diet, who had decreased levels of short-chain fatty acids and increased allergic airway inflammation.

 

How did the researchers interpret the results?

The researchers conclude that dietary fibre and short-chain fatty acids can shape the immunological environment in the lung and influence the severity of allergic inflammation. They say dietary fibre changes the composition of the gut and increases the circulating levels of short-chain fatty acids, which helps impair allergic airway inflammation.

One of the researchers, Dr Benjamin Marsland from the University of Lausanne, is quoted by the BBC as saying, "There's a very high probability it works in humans; the basic principle of fibre being converted to short-chain fatty acids is known.

"But we don't know what amount of fibre would be needed, and the concentrations of short-chain fatty acids required might be different. It is early days, but the implications could be far reaching."

 

Conclusion

The current study has discovered more about the role of dietary fibre in the gut and its effect on lung inflammation. The findings come from experiments with mice in the laboratory.

Importantly, the researchers only tested the effect of dietary fibre on airway inflammation in mice. The results of animal research often do not translate into the same results for people.

However, the basic biology of humans and mice is surprisingly similar in some aspects, so these findings give a good starting point for further study in humans.

Although these results can help scientists learn more about the role dietary fibre plays in protecting against airway inflammation, headlines stating that a high-fibre diet "prevents lung inflammation" are premature.

However, there is evidence that a high-fibre diet can protect against other chronic diseases. For example, a 2011 study found evidence that suggested a high-fibre diet could protect against bowel cancer.

If you are having problems controlling your asthma symptoms, your treatment plan may need to be reviewed. Read more about the available treatment options for asthma.

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter.

Links To The Headlines

Eating more fibre could help treat symptoms of asthma, scientists say. The Independent, January 6 2014

Asthma: Altering diet may ease symptoms. BBC News, January 6 2014

Eating plenty of fruit and veg can protect against asthma: High-fibre diet prevents lung inflammation. Mail Online, January 6 2014

Links To Science

Trompette A, Gollwitzer ES. Yadava K, et al. Gut microbiota metabolism of dietary fiber influences allergic airway disease and hematopoiesis. Nature Medicine. Published online January 5 2014 

Categories: Medical News

Could cannabis compound soothe arthritis pain?

Medical News - Tue, 01/07/2014 - 03:00

“Synthetic cannabis-like molecule developed in lab could help osteoarthritis sufferers,” reports The Daily Telegraph.

Anecdotal reports of cannabis’s ability to soothe chronic pain conditions such as osteoarthritis have been available for many years.

Aside from the obvious legal issues (cannabis is a Class B illegal drug), cannabis also carries the risk of side effects and complications such as psychosis and depression.

So a compound containing the drug’s painkilling ability without its psychoactive effects could lead to useful new treatments. 

One candidate is “JWH133” a chemical that binds to and activates the cannabinoid 2 (CB2) receptor. Receptors are proteins found on the surfaces of cells. When activated receptors cause a response inside cells. The CB2 receptor is also activated by tetrahydrocannabinol (THC), the principle psychoactive constituent in cannabis. Activating the CB2 receptor is thought to relieve pain and inflammation. 

The new research found evidence that JWH133 relieves pain in a rat model of arthritis. Importantly, the JWH133 compound is selective for CB2 receptors and does not activate cannabinoid 1 (CB1) receptors. CB1 receptors are found in the brain and are believed to be responsible for the psychological effects of cannabis.

So this suggests JWH133 may be a useful candidate for an osteoarthritis treatment. However, this is very early stage research only involving rats.

As Professor Alan Silman, medical director of Arthritis UK, says in the press coverage, this research does not support recreational cannabis use.

 

Where did the story come from?

The study was carried out by researchers from the University of Nottingham in the UK in collaboration with researchers from the University of Pittsburgh and Virginia Commonwealth University in the US. It was funded by Arthritis Research UK and the National Institutes of Health.

The study was published in the peer-reviewed journal PLOS One. PLOS One is an open-access journal, meaning that all the research it publishes can be accessed for free.

This study was reported on by the Daily Express and The Telegraph. The Telegraph made no mention of the fact that the current research was in rats. This was also unclear from the over-optimistic headline in the Express. However, the report in the Express was of a higher standard, as it explained that the research was in animals and that it would take a considerable amount of time before any pill could be available for patients.

 

What kind of research was this?

This was a laboratory experiment on animals.

The researchers wanted to test the hypothesis that activation of cannabinoid 2 (CB2) receptors would reduce osteoarthritis pain responses in an animal model of osteoarthritis.

 

What did the research involve?

To create the animal model of osteoarthritis, rats had an injection of a chemical (monosodium acetate) into one of their knees (on the left rear limb). This triggered the same kind of inflammation and functional damage to the limb that occurs in humans with osteoarthritis.

The rats were then either given a drug called JWH133 or a placebo (“dummy”) injection. JWH133 binds with and activates the CB2 receptor of cells, causing them to respond. Eight rats were injected with JWH133 and eight were injected with placebo.

Pain behaviour was determined by measuring the change in weight distribution between the limbs and by testing the rats' sensitivity to pinch and touch.

Further experiments were performed on the animal model of osteoarthritis and normal rats that had been given an injection of saline (salty water) into their knee to see how JWH133 could reduce pain.

 

What were the basic results?

Once the rats had the injection of monosodium acetate into the knee of their left rear limb to model osteoarthritis, they placed less weight on that limb and their paw was more sensitive to pinch and touch.

Repeated injections with JWH133 significantly reduced the development of pain behaviour in the osteoarthritis model rats compared to the placebo injection.

The researchers went on to perform a series of further experiments. They found that:

  • treatment with JWH133 reduced the changes in inflammation-controlling chemicals which are released by osteoarthritis model rats
  • treatment with JWH133 reduced the firing of nerve cells in the spine in response to pain in osteoarthritis model rats, but not normal rats
  • osteoarthritis model rats have higher levels of the CB2 receptor “message” (mRNA) and protein in nerve cells in the spine

The researchers then looked at the levels of CB2 receptor “message” in human spines of people who had died who had had knee osteoarthritis. They found that the more severe the disease, the lower the level of CB2 receptor “message”. The researchers say that this might reflect “events associated with later stages of joint pathology [disease]”.

 

How did the researchers interpret the results?

The researchers conclude that “activation of CB2 receptors attenuated [reduced] the development and maintenance of osteoarthritis-induced pain behaviour”. They go on to state that their “clinical and pre-clinical data support the further investigation of the potential of CB2 receptor agonists [chemicals that bind to the receptor and activate it] for the treatment of pain associated with osteoarthritis, in particular at earlier stages of the disease”.

 

Conclusion

This study found that a chemical called JWH133, which binds to and activates the cannabinoid 2 (CB2) receptor, could reduce osteoarthritis-induced pain behaviour in rats injected with a chemical to mimic the effects of osteoarthritis.

This early stage research supports the further investigation of the potential of chemicals which bind to activate the CB2 receptor as treatments for osteoarthritis-induced pain. However, so far the treatment has only been tested in a small number of rats injected with a chemical to mimic symptoms of osteoarthritis. This study does not show what positive or negative effect chemicals that activate the CB2 receptor may have in humans suffering from osteoarthritis.

Until further trials involving humans, such as a phase I trial are carried out, it is impossible to predict whether JWH133 will be effective, and probably more importantly, safe in humans.

If you are having problems coping with your arthritis symptoms, the NHS offers specialist services for people with chronic pain conditions.

Read more about NHS Services for people with chronic pain.

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter.

Links To The Headlines

Synthetic cannabis created for osteoarthritis. The Daily Telegraph, January 7 2014

‘Synthetic cannabis’ pill could end arthritis pain for millions. Daily Express, January 7 2014

Links To Science

Burston JJ, Sagar DR, Shao P, Bai M, King E, et al. Cannabinoid CB2 Receptors Regulate Central Sensitization and Pain Responses Associated with Osteoarthritis of the Knee Joint. PLoS ONE. Published online November 25 2013

Categories: Medical News

Vitamin D in pregnancy may aid child's grip

Medical News - Mon, 01/06/2014 - 13:00

"Higher levels of maternal vitamin D during pregnancy have been linked to better muscle development in children," BBC News reports.

The headline is prompted by a UK study involving more than 600 mothers and their children. It found that at the age of four, the children of women who had higher levels of vitamin D in late pregnancy had stronger hand grips than those whose mothers had lower levels of the vitamin.

Pregnant women are known to be at risk of not getting enough vitamin D. The Department of Health currently recommends that all pregnant and breastfeeding women should take a daily supplement containing 10 micrograms (0.01mg or 400 international units) of vitamin D. In the current study, less than 10% of the women were taking these supplements in late pregnancy.

However, this study did not follow these children up past the age of four, so we don't know for sure whether these differences remain as they get older. These results would need to be confirmed by other studies before they are seen as conclusive.

Despite this, the current study reminds us that it's important for pregnant women to get enough vitamin D. If you are pregnant, talk to your GP or midwife about ensuring you get the right nutrients and supplements.

Read more advice about vitamins and nutrition in pregnancy.

 

Where did the story come from?

The study was carried out by researchers from the University of Southampton and other research centres in the UK. It was funded by the Medical Research Council and several other UK charities and research institutions.

The study was published in the peer-reviewed Journal of Clinical Endocrinology and Metabolism.

BBC News' reporting of the study is accurate as it generally covers the study reasonably. However, the Daily Mirror makes a fundamental error when reporting the recommended levels of vitamin D supplementation for pregnant women.

Pregnant women are recommended to take an extra 10 micrograms of vitamin D a day, not 10 grams (a million times higher) as the Mirror advised.

Taking such a high dose of vitamin D regularly could lead to side effects such as dehydration, nausea, vomiting and kidney damage. But this is unlikely to happen in the real world, as a 10 gram vitamin D supplement shouldn't be available to buy.

 

What kind of research was this?

This study was part of a prospective cohort study called the Southampton Women's Survey. The current analysis looked at the link between mothers' vitamin D levels in pregnancy and their children's muscle strength in early childhood.

The researchers report that other studies have found links between maternal vitamin D levels in pregnancy and child body composition outcomes such as bone and fat mass. There is little information about the potential effect of maternal vitamin D levels in pregnancy on child strength, so researchers wanted to see if there was a link.

This study design is the best way to assess the link between a naturally occurring exposure and an outcome. The main limitation is that women who differ in one characteristic (vitamin D levels in pregnancy) may also differ in other ways, for example, unmeasured health, lifestyle and socioeconomic factors. This makes it difficult to tell for certain which of these factors is affecting the outcome.

 

What did the research involve?

The study measured the vitamin D levels of women in pregnancy by taking samples of their blood. Their children's grip strength was assessed once they reached the age of four. The researchers then looked at whether a mother's vitamin D levels in pregnancy were related to how strong the child was.

The Southampton Women's Survey enrolled more than 15,000 young women aged 20 to 34. The current study only included women who became pregnant during the study and did not have twins or triplets.

The women reported on their lifestyles and had characteristics such as their height and weight measured at the start of the study and during pregnancy. At 34 weeks of pregnancy, they also had a blood sample taken and vitamin D levels were measured. After birth, the researchers asked the women about how long they breastfed their baby.

The children had their height, weight and body composition assessed at the age of four. They also had their hand grip strength measured as an indication of their muscle strength. A subset of the children also had their levels of physical activity measured by wearing monitoring devices for seven days.

The researchers analysed data for the 678 mother-child pairs that had all the necessary data. They then assessed whether the children's hand grip strength was related to their mother's vitamin D levels during pregnancy.

They took into account factors that could influence the results, known as confounders. These included:

  • the child's gender
  • exact age
  • height
  • current milk intake
  • duration of breastfeeding
  • the mother's smoking status in late pregnancy
  • walking speed in late pregnancy
  • late pregnancy body fatness (assessed either using triceps skinfold thickness or body mass index)
  • age at delivery
  • how many children they had
  • social class

They also assessed whether children's physical activity levels or the season the different measurements were taken in affected the results.

 

What were the basic results?

The researchers found that only 9.2% of women were taking a vitamin D supplement in late pregnancy (34 weeks of gestation). The women's average (median) intake of vitamin D in late pregnancy was 136 international units (IU) per day (3.4 micrograms).

Higher maternal levels of vitamin D in pregnancy were associated with greater hand strength in the child at the age of four, even after taking into account potential confounding factors.

They found that maternal levels of vitamin D in pregnancy were also associated with some of the measures of the child's lean mass, but not others. The associations with lean mass were not statistically significant once potential confounding factors were taken into account.

  

How did the researchers interpret the results?

The researchers say that their results suggest that exposure to higher levels of vitamin D in the womb may influence a child's muscle development. This seems to act by increasing strength, rather than the amount of muscle.

They say that vitamin D supplementation in pregnancy may improve child muscle development, but that this needs to be confirmed in an intervention study before any recommendations are made.

 

Conclusion

This study suggests that a mother's vitamin D levels in pregnancy may affect their child's muscle strength in early childhood. The study's strengths include the fact that it collected data prospectively as well as taking standardised information and measurements from the mothers and children.

The researchers note that some limitations of their study are the difficulties in carrying out body composition scans and hand grip tests in children. The study also only measured vitamin D levels at one point in pregnancy, and levels may have differed at various points in the pregnancy. Also, only one measure of child strength was taken (hand grip) at one time point, and this may also vary if multiple measurements were taken.

The current study didn't follow these children up past the age of four, so we don't know for sure whether these differences remain as they get older. Ideally, these results would be confirmed by other studies before they are seen as conclusive.

It's also not possible to say to what extent the differences in grip strength have any impact on the child's general health or wellbeing.

Pregnant women are known to be a group at risk of not getting enough vitamin D. The Department of Health currently recommends that all pregnant and breastfeeding women should take a daily supplement containing 10 micrograms (0.01mg or 400IU) of vitamin D. Worryingly, less than 10% of the women in the current study were taking such a supplement in late pregnancy.

Overall, while the study does not provide conclusive proof of a direct link between vitamin D in pregnancy and child muscle strength, it appears to reinforce the importance of vitamin D intake in pregnancy. Women who are pregnant can talk to their healthcare professional to ensure they are getting the right nutrients and supplements.

Read more about vitamin supplements in pregnancy here.

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter.  

Links To The Headlines

Vitamin D 'boosts child muscles'. BBC News, January 3 2014

Mothers who take plenty of vitamin D during pregnancy have babies with stronger muscles. Mail Online, January 3 2014

Vitamin D in pregnancy increases children's strength. Daily Mirror, January 4 2014

Links To Science

Harvey NC, Moon RJ, Sayer AA, et al. Maternal Antenatal Vitamin D Status and Offspring Muscle Development: Findings From the Southampton Women's Survey. The Journal of Clinical Endocrinology and Metabolism. Published online October 31 2014

Categories: Medical News

Experts say sadness is wrongly being medicalised

Medical News - Mon, 01/06/2014 - 03:00

Two experts have warned that antidepressants are being “doled out as cure for simple sadness,” reports The Daily Telegraph.

The news is based on an opinion piece written by two professors in the British Medical Journal. It is one of an ongoing series of articles looking at the potential harms of overdiagnosing different conditions.

The authors argue the current criteria for diagnosing depression includes wide groups of people with mixed severities of the condition, and are therefore too broad.

They are concerned that diagnostic criteria are “medicalising” normal human experiences such as grief, and other life stresses. They highlight the importance of providing appropriate support – not antidepressants – for these individuals. The authors also note the importance of GPs identifying people with severe depression and providing them with better access to adequate evidence-based care.

They are also concerned that despite studies suggesting the number of people with depression in the general population has stayed roughly the same in recent years, the number of diagnoses of the condition in general practice and prescriptions of antidepressants are increasing. They say this is not due to better diagnosis, but rather to overdiagnosis.

This article represents the expert authors’ viewpoints based on various studies and observations. This was not a systematic review and therefore it is possible that not all evidence relevant to depression diagnosis and prevalence has been considered. Other professionals may have differing views.

 

Where did the story come from?

The article was written by two professors of primary medical care and psychiatry from the University of Liverpool and Duke University Medical Center in the US. It was a discussion piece, which did not receive any specific funding.

One of the authors had worked on previous versions of the US diagnostic criteria for depression – the fourth version of the American Psychiatric Association's “Diagnostic and Statistical Manual of Mental Disorders” or DSM-IV.

The piece was published in the peer-reviewed British Medical Journal (BMJ) as part of a series of articles about over-diagnosis – which is when a person is diagnosed as having a condition that would not have gone on to cause them harm had it not been diagnosed. This means that when these people are treated for the condition they don’t stand to benefit, but they are at risk of the treatment’s side effects.

 

What kind of article was this?

This was a discussion article, commissioned as part of a series of similar articles discussing the potential risks to patients of expanding definitions of different diseases and use of new methods of diagnosis.

The article specifically looked at the potential for overdiagnosis and overtreatment of depression resulting from the new classification system. The authors discuss issues such as the changing views of the definition of depression, changes in how common diagnoses of depression are and the use of antidepressants, potential harms of over-diagnosis, and how the situation can be improved.

The article did not aim to be a systematic review, so does not carry out a systematic search to identify all relevant evidence on this issue. The authors cite information from various research papers including systematic reviews, as well as academic books and other sources to show the basis for their views. However, it is possible that not all evidence relevant to depression diagnosis and prevalence has been considered.

 

What did the article say is the problem?

The authors start out by saying that in the past few decades, there has been an increasing tendency to diagnose patients with sadness and distress as having depression, and to offer them antidepressant drugs.

Definitions of depression

They report that:

  • The first formal criteria for the diagnosis of depression (“major depressive disorder” or MDD) were published in 1980 (as part of the DSM-III classification system)
  • These criteria identify a mixed group of patients and are “so loose that, in everyday clinical practice, ordinary sadness can be easily confused with clinical depression”.
  • The most recent version of these criteria (DSM-5) has broadened the definition of depression further, as it now allows grief from bereavement to be classified as MDD if it has persisted for longer than two weeks.
  • They say that this change in DSM-5 was designed to provide more patients with access to effective treatments, but has provoked controversy and concern about “medicalisation” of a normal human experience. They believe this change was a mistake, as those with bereavement have different symptom profiles to those with MDD.
Number of diagnoses of depression and antidepressant prescriptions

The authors report that:

  • Surveys have found that the proportion of people with depression in the general population in the US and UK has remained stable in recent decades.

However:

  • The number of people diagnosed with depression among recipients of the US medical insurance Medicare doubled between 1992-5 and 2002-5.
  • Prescribing of antidepressant medication increased by over 10% each year in England between 1998 and 2010, mainly due to increases in long term prescriptions.
  • They say that these increases are not because doctors are getting better at diagnosing the condition, instead it is due to over-diagnosis.

A pooling (meta-analysis) of 41 studies suggested that for every 100 cases seen in primary care there were more cases of people incorrectly diagnosed with depression (15 cases), than those who had depression that had been missed (10 cases) or who had been correctly diagnosed with depression (10 cases). Another study in the US found that more than 60% of adults diagnosed by their doctor as having depression did not currently meet criteria for a diagnosis of depression, but many were still taking medication for the condition.

 

What do the authors think has been causing this problem?

The authors suggest that the broad criteria for diagnosing depression are in part a result of “heavy drug company marketing” and a focus among many psychiatrists on the biology of psychiatric symptoms rather than their psychological, social, and cultural aspects. They say that patients “often request treatment for symptoms of sadness”, and that doctors “can feel obliged to offer… a diagnosis of major depressive disorder” and patients may also feel obliged to accept this diagnosis.

 

What are the potential harms of over-diagnosis?

The authors note that meta-analyses have suggested that antidepressants have little or no effect in mild depression. They say that there is no evidence that people with uncomplicated bereavement benefit from antidepressants, and little evidence from trials about their effects in people with complicated grief.

They say that turning grief and other life stresses into psychiatric disorders “represents medical intrusion on personal emotions”. They also say that it adds unnecessary drug treatment and costs, and takes resources away from those with severe mental health problems who really need them.

 

How did the article say the situation could be improved?

The authors call for diagnostic criteria for depression to be tightened. They suggest that:

  • Milder symptoms should be persistent throughout the day, present for at least a month or two, and cause significant distress or impairment for a diagnosis of mild major depression to be made.
  • Existing diagnostic criteria should be accurately applied in diagnosing moderate to severe depression, with diagnoses made only when there are substantial symptoms and clear associated impairment.
  • People presenting with milder or loss-related symptoms should not be dismissed, but the focus should be on time, support, advice, social networks, and psychological interventions.

They say that the problems with DSM-5 – a US based diagnostic classification system – could be avoided in ICD-11 – the update to the UK-based diagnostic classification system that is currently being prepared.

The authors also say that:

  • GPs should focus on identifying people with severe depression and provide them with better access to adequate evidence based care.
  • Drug companies should be stopped from marketing antidepressant medication to physicians and the public (the latter is already not allowed in the UK), and from supporting professional organisations and consumer groups.
  • People with mild depression or uncomplicated grief reaction usually have a good outlook and don’t need drug treatment
  • Doctors should sensitively discuss with patients the potential for the placebo effect with antidepressant medication, as well as the side effects and costs associated with these drugs.
  • Doctors should listen carefully to patients, and promote the effects of time, exercise, support, and changing circumstances where possible to help deal with life problems, as well as patients sharing their experiences with each other.

 

What does UK guidance say about treating mild depression?

Notably, the UK guidance from the National Institute for Care Excellence for the management of depression in adults, currently says that the “first-line” treatment approach for mild depression is with psychological interventions such as cognitive behavioural therapy (CBT) or physical activity programmes.

Therefore the authors’ suggestions about the treatment of mild depression are generally consistent with current recommended practice in the UK.

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter.

 

Links To The Headlines

Depression drugs doled out as cure for simple sadness, warns expert. The Daily Telegraph, January 5 2014

Categories: Medical News

MPs criticise Tamiflu secrecy and stockpiling

Medical News - Fri, 01/03/2014 - 14:00

"Drug companies accused of holding back complete information on clinical trials," The Guardian reports.

MPs have just published a report expressing concern that drug companies are withholding evidence about how effective drugs such as Tamiflu actually are.

The report, from the House of Common Public Accounts Committee, says it heard evidence that clinical trials of medicines that have a favourable result are about twice as likely to be published as those giving unfavourable results.

This has been a long-recognised issue in evidence-based medicine and is known as publication bias.

Though despite efforts by both researchers and regulators to overcome publication bias, many commentators maintain it is an ongoing problem.

In particular, the report considers the case of Tamiflu, the antiviral medicine used in the treatment of both seasonal flu and swine flu.

It says that in the last few years the government spent £424 million on stockpiling Tamiflu in case of a flu pandemic. However, there is little agreement as to how effective the drug is, particularly in preventing complications and deaths from flu.

Discussions on the issue, it says, have been hampered because not all the information from clinical trials on Tamiflu have been made available.

The report also voices concern as to whether the National Institute for Health and Care Excellence (NICE), which advises on the use of drugs in the NHS, has appropriate access to all the information made available to the regulatory bodies as part of the licensing process. 

The report calls for greater transparency and recommends that all clinical trials, whether published or unpublished, should be made available for wider scrutiny.

 

Who produced the report?

The report comes from the Committee of Public Accounts, a parliamentary committee comprising members from all the major political parties. The Committee’s role is to examine how effectively and efficiently public money is spent, focusing in particular on value for money criteria.

Before producing a report it takes evidence from relevant sources and experts.

In this report evidence was taken from:

Written evidence was also taken from:

  • Roche, the manufacturers of Tamiflu
  • the Cochrane Collaboration, an independent non-proft body that carries out systematic reviews on the evidence for specific treatments

 

What does the new report say?

The latest report from the Committee covers several related areas:

  • The availability of clinical trial results
  • How the agencies involved in licensing and approving medicines share information
  • The stockpiling of Tamiflu
Clinical trials

The Committee points out that the results of clinical trials on humans are the “key evidence” used by regulators, researchers and clinicians to assess whether a medicine works and how safe it is.

Medicine manufacturers submit evidence on products they wish to market in the UK to the Medicines and Healthcare Products Regulatory Agency (MHRA) or the European Medicines Agency (EMA).

The Committee says it was “surprised and concerned to discover that information is routinely withheld from doctors and researchers about the methods and results of clinical trials on treatments currently prescribed in the United Kingdom”.

The scope for independent scrutiny of a medicine’s effectiveness is undermined by the fact that the full methods and results of many clinical trials are not made available to doctors and researchers, it argues. This undermines the ability of doctors, researchers and patients to make informed decisions about which treatment is best.

The problem of non-publication of clinical trial results has been known since the mid-1980s, say the MPs, without adequate action being taken by government, industry or professional bodies.

This now presents a serious problem because the medicines in use today came on to the market – and were therefore researched – over the preceding decades.

The Committee also heard evidence that trials with positive results are about twice as likely to be published as trials with negative results.

It also says that none of the latest proposals from regulators or industry adequately address the issue of access to the results of trials from previous years on the medicines in use today.

The role of NICE and the MHRA

The report also comments on the role of NICE, the body that provides evidence-based guidance to health professionals on treatments; and on the Medicines Healthcare and Regulatory Products Agency (MHRA), the government body responsible for regulating and licensing all medicines.

It says that that NICE and the MHRA do not routinely share information provided by manufacturers during the process for licensing medicines. It explains that when applying for a license for a drug, manufacturers have a legal obligation to provide all the information on the safety and efficacy of a medicine that is required by European regulators.

However, NICE does not have statutory powers to demand information from manufacturers, in contrast to the Institute for Quality and Efficiency in Healthcare in Germany, which performs a similar role to NICE.

NICE seeks confirmation from the medicine manufacturer’s UK medical director on the completeness of information, but this may not include all clinical trials in other parts of the world, not least because UK medical directors may themselves not have full information.

However, there is no routine sharing of the information provided by manufacturers to regulators as part of the licensing process with NICE. This leads to the risk of omissions and duplication in the collection of evidence.  

The stockpiling of Tamiflu

The report points out that between 2006-07 and 2012-13, the Department of Health spent £560 million on stockpiling two antiviral medicines for use in a flu pandemic – £424 million on Tamiflu (oseltamivir) and £136 million on the other antiviral used to treat flu, Relenza (zanamivir).

Yet it says there remains a lack of consensus over how well Tamiflu works. There also disagreement about whether medicine regulators and NICE received all the information on Tamiflu during the licensing process.

The MHRA is confident that European regulators received all the information on Tamiflu; yet according to the Cochrane Collaboration, (the independent body that publishes systematic reviews of the evidence on treatments) this was not the case.

It wrote to the Committee to draw attention to trials where the Cochrane Collaboration concluded the European regulators had incomplete information. “It is plain that for many large trials no information was available, and that for many more trials only partial information was available,” the Committee concludes.

The Committee shares the concern expressed by the Cochrane Collaboration when it wrote: “We find it perplexing that the regulators continue to state that they had all the available evidence.”

It says the Cochrane Collaboration is now receiving full clinical study reports from Roche, the manufacturer of Tamiflu. This will enable it to complete its review of the effectiveness of Tamiflu with complete information for the first time.

It concludes: “Whether or not the Cochrane Collaboration’s overall recommendation changes, it is extremely concerning that there has been a five-year delay and that there continues to be a lack of clarity over who saw what.”

It also points out that The Department of Health wrote off £74 million of Tamiflu as a result of poor record-keeping by the NHS on how the medicine had been stored during the 2009 flu pandemic. During the swine flu pandemic, Tamiflu was distributed to many places around the country. When unused stocks were returned, it was not clear whether they had been stored, as required, below 25C.

The Department of Health has put in place additional guidance for the storage of antivirals following distribution during a pandemic.

The case for stockpiling antiviral medicines at the current levels is based, it says,” on judgement rather than evidence of their effectiveness during an flu pandemic".

It says that despite there being only limited evidence the business case developed by the Department of Health assumed Tamiflu would give a 40% to 50% reduction in complications and mortality. This assumption was based on advice from a range of experts including the Department’s Scientific Pandemic Influenza Advisory Committee.  

 

What does the report recommend?

The report makes several key recommendations which include:

  • The Department of Health it says should take action to ensure that the full methods and results are available to doctors and researchers for all trials on all uses of all treatments currently being prescribed.
  • The Department and the MHRA should ensure, both prospectively and retrospectively, that clinical trials, including methods and results, are registered on an appropriate registry that is available for wider independent scrutiny.
  • NICE should ensure that it obtains full methods and results on all trials for all treatments that it reviews and routinely audit the completeness of this information.
  • NICE and the MHRA should put in place a formal information-sharing agreement to ensure when NICE appraises medicines it has access to all of the information provided to regulators.
  • Once the Cochrane Collaboration has completed its review of Tamiflu using all clinical study report information, further consideration is required into whether it is necessary to revisit previous judgments about the efficacy of Tamiflu.

 

What does the drug industry say?

In a response to the report, Bina Rawal, the medical and innovation director of The Association of the British Pharmaceutical Industry (ABPI), which represents drug manufacturers in the UK, said:

"It is misleading to suggest that the pharmaceutical industry routinely withholds clinical trial data from doctors and researchers.

“In late 2013, an ABPI-commissioned study was published in a peer-reviewed journal. This study highlighted a positive trend of increasing levels of disclosure for industry-sponsored clinical trials, with almost nine out of 10 of all industry-sponsored clinical trials disclosed by January 31 2013. The research covers new medicines approved between 2009 and 2011, which includes trials conducted over the preceding 10 or more years – i.e. during the entire development programme.

“However we recognise that there is still work to be done and we are continuing on a journey to achieving greater clinical trial transparency. The ABPI has made available a new clinical trial disclosure toolkit to assist companies and will continue to engage with key stakeholders on this issue.”

 

So Tamiflu doesn’t work?

As the Committee points out, not enough evidence has been made publically available to know how well Tamiflu works. The Cochrane Collaboration’s systematic review into the effectiveness of Tamiflu in preventing and treating flu in adults and children – published in January last year – said it was incomplete because of difficulties obtaining sufficiently detailed information from the manufacturer (Roche).

Overall, the review included 25 studies, but had to exclude 42 relevant studies due to the lack of patient information or unresolved problems in the data.

While a review of Relenza undertaken at the same time was postponed due to new information about how the drug affected individual patients being made available by the manufacturer (GlaxoSmithKline).

As the Committee says, the debate on whether Tamiflu is effective continues. The simplest way to resolve it would be to allow independent reviewers to access the full existing results of studies into it.

As with most things in medicine, prevention is better than the cure. If you are in a vulnerable group known to be more at risk for complications from flu then you should ensure your flu vaccinations are up to date.

Read more about who should get the flu vaccine.

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter.

Links To The Headlines

Drug companies accused of holding back complete information on clinical trials. The Guardian, January 3 2014

Drug companies 'withholding research' from doctors, MPs warn. The Daily Telegraph, January 3 2014

Drugs companies 'routinely withhold results of medical trials' from doctors, researchers and patients. The Independent, January 4 2014

Our £400m stockpile of flu medicine that might not even work: MPs warn there is no clear evidence Tamiflu is effective. Daily Mail, January 4 2014

Categories: Medical News

Buffaloberries – 2014's new 'superfood'

Medical News - Fri, 01/03/2014 - 13:30

"The buffaloberry is the new superfood of 2014," the Mail Online declares. But at this stage there is very limited evidence to back up the hype.

The website reports on laboratory research analysing the chemical constituents of the buffaloberry fruit. This is a fruit native to northern and western North America. Buffaloberry has historically been used as a food source by North American indigenous peoples but has had limited commercial production.

The researchers found that the fruit contained lycopene. Lycopene belongs to the "carotenoids family" – organic pigments found in plants. It is also an antioxidant, a substance that protects against cell damage at the molecular level. The main antioxidant present was actually an acidic derivative of lycopene, called methyl apo-6’-lycopenoate (MA6L). They also found high concentrations of phenols, which give the fruit a "tart" taste, and are believed to have possible anti-inflammatory effects.

It is possible that buffaloberry could have beneficial antioxidant effects, but the current study does not provide evidence that it could reduce risk of disease and promote wellbeing. Importantly, as the researchers say, while the possible effects of lycopene on human health have been studied, those of buffaloberry’s main antioxidant, MA6L, haven’t.

There is no single dietary quick fix to good health. The best way to promote good health is to eat a healthy balanced diet, including a wide variety of different vegetables and fruit, taking regular exercise, avoiding smoking and limiting alcohol intake.

  

Where did the story come from?

The study was carried out by researchers from Ohio State University and South Dakota State University and was funded by a Griffith Undergraduate Research Fellowship and research funds from Special Grants for Dietary Intervention.

The study was published in the peer-reviewed Journal of Food Science.

Overall the Mail Online is a little premature in hailing the buffaloberry the new superfood based on research that only looked at the chemical constituents of the berry. Researchers did not assess what effect the berries had on health outcomes in a human population.

Still, we would not be surprised if this article led to a flurry of similar articles extoling the benefits of this new superfood, as has occurred in previous years.

Read more about the evidence behind so-called superfoods.

 

What kind of research was this?

This was a laboratory study designed to examine the chemical constituents of buffaloberries.

The buffaloberry plant (Shepherdia argentea) is native to a wide variety of habitats, from stream bansk to dry upland grasslands of North America. It has historically been used as an important food source by North American indigenous peoples.

However, its commercial production has been limited. The buffaloberry plants are said to produce red-coloured fruits rich in carotenoid and phenolic antioxidants. This study looked at the chemical constituents of seven different selections of buffaloberries grown in Dakota.

 

What did the research involve?

Buffaloberries were collected from wild plants in five locations in North Dakota and two locations in South Dakota in September and freeze-dried in preparation for analysis.

Laboratory methods were used in order to extract and quantify all the carotenoid pigments, including lycopene and its derivatives. Additional methods were used to look at total phenol content and total water-soluble antioxidant capacity.

The researchers also examined fruit quality, including looking at its sugar content and acidity levels to see if it could have commercial potential.

 

What were the basic results?

The main carotenoid pigments found in the buffaloberries were lycopene (red-orange pigment found in fruits such as tomatoes and peppers), and an acidic lycopene derivative called methyl apo-6’-lycopenoate (MA6L). MA6L had the highest concentration and comprised just over half of the total carotenoid antioxidants. There were only trace amounts of other, unidentified, carotenoids.

The buffaloberries also contained high total phenol concentrations. Phenols cause the fruit to have a ‘tart’ taste. And its antioxidant levels compared favourably to fruits such as raspberries, strawberries and elderberries.

When looking at fruit quality, the researchers report that the buffaloberry is very high in sugar, but this is balanced by an acidity and phenol content that could make them desirable as fresh fruit, and for wine production.

 

How did the researchers interpret the results?

The researchers say that buffaloberry fruits contain principally lycopene and the acidic derivative methyl apo-6’-lycopenoate, which they say "may provide health benefits and marketable produce for consumption and sale".

They report how the buffaloberry flourishes on the American Indian Tribal Reservations of the Dakotas, "yielding copious amounts of health-beneficial fruit for fresh and processing markets". They say the fruit, which is a traditional food of the indigenous peoples of the region, has already found favour with several commercial wine producers.

 

Conclusion

This research was analysing the chemical constituents of the buffaloberry fruit, which is native to various habitats of North America. Buffaloberry has historically been used as a food source by North American indigenous peoples but has had limited commercial production.

The researchers found that the main antioxidant present in the fruit was the acidic lycopene derivative methyl apo-6’-lycopenoate (MA6L). MA6L has reportedly been found also to be a major chemical constituent of other closely related North American berries, such as soapberry fruit.

However, by contrast soapberry is said to be practically inedible due to its intensely bitter taste.

Therefore the researchers consider that the abundance of this caretenoid in buffaloberry could have practical marketing potential and possible health effects. The crucial point though, as the researchers say, is that the effects of MA6L upon human health is still unknown and still has to be evaluated.

The concentration of phenols was also high and said to compare favourably to other berries such as strawberries and raspberries. The researchers say that phenolic compounds are thought to have anti-inflammatory properties, though it is believed that any such effect is likely to be the combined effect of several antioxidants rather than just a single phenol.

Overall it is possible that the lycopene, M6AL and phenols found in buffaloberries could have beneficial antioxidant effects, but without further evaluation it should not be concluded that buffaloberry is a superfood surpassing all other fruits and vegetables. The current study does not provide evidence that this is a single miracle food that could reduce risk of disease and promote wellbeing.

If marketed, buffaloberries could one day be a useful addition to a balanced diet, but relying on a single food source to keep you healthy is not a good idea.

A healthy balanced diet should contain food from the four main food groups – fruit and vegetables; starchy foods such as rice; protein-rich food such as meat and beans; and calcium-rich food such as dairy products. Read more about what constitutes a balanced diet

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter.

Links To The Headlines

Goodbye, goji berry! The buffaloberry is the new superfood of 2014... but what the heck is it? Mail Online, January 2 2014

Links To Science

Riedl KM, Choksi K, Wyzgoski FJ. Variation in Lycopene and Lycopenoates, Antioxidant Capacity, and Fruit Quality of Buffaloberry (Shepherdia argentea [Pursh]Nutt.) Journal of Food Science. Published online October 8 2013

Categories: Medical News

Early animal research into blocking breast cancer

Medical News - Thu, 01/02/2014 - 14:00

"'An injection that prevents breast cancer is being developed by scientists," is the news on the Mail Online website.

This news seems a heartening way to start the year, but a caveat is that the research is in the very early stages – as yet only tested in mice.

The researchers were interested in a type of breast cancer known as ductal carcinoma in situ (DCIS).

In DCIS the cancerous cells are contained within the ducts in the breast, and not spread to other breast tissue. The problem with DCIS is that it is currently impossible to predict whether the cancer will remain inside the duct (so will not require treatment) or become invasive and spread into other parts of the breast. This means that some women with DCIS will undergo invasive treatment unnecessarily.

This research involved genetically engineered mice designed to develop DCIS-like tumours that eventually spread. They found that a gene called Hox1A seemed to be involved in stimulating the growth of the DCIS-like tumours. They then went on to use an injection of specially designed nanoparticles into the mammary tissue, designed to "turn-off" the Hox1A gene.

They found that the injection stopped three-quarters of the mice from developing tumours at 21 weeks. However, the researchers don’t yet know if the tumours might develop later in these mice, or are stopped completely.

These findings are definitely worth more investigation, but, as yet, implications for human breast cancer prevention or treatment are still uncertain.

 

Where did the story come from?

The study was carried out by researchers from Harvard University and other research institutions in the US. It was funded by the US Department of Defense and the Wyss Institute for Biologically Inspired Engineering. The study was published in the peer-reviewed journal Science Translational Medicine.

The Mail Online’s headline and photos of women (including Angelina Jolie) may lead people to believe that this research is more advanced than it is. As yet, this technique has only been tested in mice, so its effects in humans are not known. 

So despite the Mail Online’s claims, it is far too early to know whether it will “spare thousands of women the trauma of surgery”. (The injection was also not given intravenously as the Mail Online suggests, it was injected directly into the mice’s mammary tissue.)

 

What kind of research was this?

This was laboratory and animal research aiming to understand more about which genes are involved in the development of breast tumours and to see if blocking these genes could stop tumour progression.

This early stage research was carried out mainly in mice, but researchers hope that their findings will be applicable in humans. The genetically engineered mice they used start to show abnormal mammary cells at about 12 weeks of age, before developing growths that are contained within the mammary glands at about 16 weeks, and then progress to invasive tumours at 20 weeks of age.

At the point where the growths are contained within the mammary glands, they resemble ductal carcinoma in situ (DCIS) in humans. DCIS is a very early stage of breast cancer where there are abnormal cancer cells in the breast ducts, but the cancer has not spread out into the breast tissue. It is estimated that up to half of people with DCIS will go on to develop invasive breast cancer. This is where the cancer has spread into the breast tissue with potential for spread to the lymph nodes and other tissues and organs of the body. In the remainder of people the abnormal cells will remain confined to the breast ducts and they will never develop invasive breast cancer.

The difficulty for scientists and medical professionals is that they can’t tell in advance whether DCIS will progress to invasive cancer or will be the non-aggressive kind that remains confined to the ducts. So currently all women with DCIS are assumed to be at risk of invasive breast cancer and are offered treatment as a precaution, such as surgery or radiation. Doctors would like to be able to use less invasive treatments for DCIS that would still be effective, and also have fewer side effects. The current research aimed to test an approach that could eventually provide a way to do this.

 

 

Links To The Headlines

Breast cancer jab ‘prevents the disease in 75% of cases’: Treatment could spare thousands of women the trauma of surgery. Mail Online, January 1 2014

Links To Science

Brock A, Krause S, Li H, et al. Silencing HoxA1 by Intraductal Injection of siRNA Lipidoid Nanoparticles Prevents Mammary Tumor Progression in Mice. Science Translation Medicine. Published online January 1 2014

Categories: Medical News