The use of physical restraint in psychiatric hospitals has been widely reported after the publication of a report by the mental health charity MIND on the use of the practice in England. The report said that last year almost 40,000 incidents of physical restraint were recorded, with almost 1,000 cases of physical injury after a patient had been physically restrained.

MIND is particularly concerned about the use of "face-down restraint", which it says can be life-threatening and was used more than 3,000 times last year. The government is said to be considering a ban on the practice and has reportedly ordered an investigation into its use in two English trusts.

The charity's report says that from the figures it has compiled, it is clear there is "huge variation" in the use of physical restraint across England. It is calling for the government to establish national standards for the use of physical restraint and accredited training in its use for healthcare staff.

What is physical restraint in mental healthcare?

MIND quotes one definition of physical restraint from the Care Quality Commission, which says it is "the physical restraint of a patient by one or more members of staff in response to aggressive behaviour or resistance to treatment".

MIND defines "face-down restraint" as when someone is pinned face down (prone) on the floor and is physically prevented from moving out of this position. The charity says this is dangerous and can be life-threatening because of the impact it has on breathing.

Why did MIND investigate the use of physical restraint?

MIND points out that healthcare staff have a challenging job – physical intervention is often used to manage a person's behaviour if they are deemed to be a risk to themselves or others as a result of their mental health problems.

It says the issue poses a huge challenge to clinical staff, as well as those managing healthcare: "We have a huge responsibility to ensure that as clinicians the power invested in us is not abused."

What does the law say about physical restraint?

The law says that if someone is detained in hospital under the Mental Health Act (1983), staff are entitled to exercise a degree of control over them. For example, staff are allowed to prevent someone detained under the act from leaving hospital.

Under the law, force may be used to achieve this if necessary, but it must be reasonable and proportionate. The act's code of practice explains that restraint is a response of last resort and gives detailed guidance for managing disturbed or aggressive behaviour.

How did MIND uncover the extent of the use of physical restraint?

The charity sent requests under the Freedom of Information Act to all 54 mental health trusts in England, asking how they used physical restraint and the procedures and training in place governing its use. They asked for a range of data for the year 2011-12, with information broken down by both gender and ethnicity.

It received responses from 51 trusts, one of which declined the request on the grounds of cost and time. The charity says it did not approach independent providers, and further research is needed in the use of physical restraint in independent mental health units.

The charity also commissioned an independent inquiry into mental healthcare in 2010-11. Its report, published in 2011, included patients' experiences of being physically restrained.

What did MIND find out about physical restraint?

• The charity says it found a "staggering" variation in the use of physical restraint in mental health trusts. In a single year, one trust reported 38 incidents, while another reported 3,346. In total, 39,883 incidents were reported. The level of variation is "appalling", MIND says, with the data suggesting that some people may be being restrained repeatedly.
• Only half of the trusts contacted reported the use of face-down restraint, which was used in more than 3,439 incidents overall. More than half these incidents occurred in just two trusts. Four mental health trusts reported there had been no use of face-down restraint.
• Just over half of trusts responded to questions on the use of physical restraint to administer medication. More than 4,000 such incidents were reported.
• Half the trusts responded to questions about police involvement in physically restraining patients, with 361 such incidents reported.
• There were 949 incidents of physical injury following physical restraint, reported by 62% of trusts. Recorded incidents of harm varied from zero to 200.
• One quarter of trusts reported incidents of psychological harm following physical restraint, of which there were 96.
• There were 111 complaints about physical restraint reported by 68% of trusts.

The charity also says it received very little information on ethnicity and gender, with many trusts saying they did not collect this information. Failure to record ethnicity of patients being physically restrained is worrying, MIND says, given that people from black and ethnic minority backgrounds are "over-represented" in hospitals as detained patients.

What do people who have been physically restrained say?

MIND includes in its report some quotes from people who have experienced or witnessed physical restraint. It says many are taken from interviews it conducted earlier this year, although it does not give details of the patients.

For example: "It was horrific … I had some bad experiences of being restrained face down with my face pushed into a pillow. I can't begin to describe how scary it was, not being able to signal, communicate, breathe or speak."

Another recalled: "It made me feel like a criminal, like I had done something wrong, not that I was just ill and needed to get better."

And another person told MIND: "I've suffered physical abuse when I was younger, and being held down where someone forces their weight on you is triggering for me … it's the last thing that's going to make me conform; I don't want them touching me."

What does MIND recommend?

MIND is calling on the government to urgently ban face-down physical restraint in all healthcare settings and to include its use in the list of "never events" – events that should never occur in a healthcare setting.

It also wants the government to introduce national standards for the use of physical restraint and accredited training for healthcare staff in England. The principles of the training should be "respect-based" and endorsed by people who have experienced physical restraint. MIND has called on NHS England to introduce standard methods of fully recording the details of cases of physical restraint.

The charity also wants staff working in mental health units to commit to working without coercion, to use alternatives and communication skills to build relationships, and to ensure that physical restraint is only ever used as a last resort.

MIND also points out that overcrowded, noisy wards with "limited therapeutic input" can be a trigger for patient distress and challenging behaviour. It says that the aim of inpatient mental health wards should be to provide a safe and therapeutic environment encompassing the patients' needs. Better communication with patients and creating care plans that respond to their needs and identify triggers for distress can all help staff manage crises.

What happens now?

According to a BBC News report, health minister Norman Lamb is "very interested" in "just banning face-down restraint". He has also reportedly ordered a "specific investigation" into the use of face-down restraint in two English trusts: Northumberland, Tyne and Wear (where face-down restraint was reportedly used 923 times in 2011-12) and Southampton.

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

Links To The Headlines

'Excessive' use of face-down restraint in mental health hospitals. BBC News. June 18 2013

Ministers consider ban on face-down restraint in mental hospitals. The Independent. June 19 2013

Mental health trusts still using dangerous face-down restraint. The Times. June 19 2013

“Severe air pollution ‘can double risk of having autistic child’,” reports The Times.

If you’re a parent-to-be you shouldn’t be unduly worried by this story, as the science it’s based on cannot and does not show a definite link. And other than moving house or changing jobs, avoiding environmental pollutants is likely to prove difficult.

This frightening headline was based on research into the exposure to environmental pollutants of mothers with children diagnosed with autism spectrum disorder (ASD).

The study compared women in the highest 20% pollution exposure category with those in the lowest 20% of pollution levels. It found exposure to diesel, lead, manganese, mercury, methylene chloride (an industrial solvent), and an overall measure of metals were all significantly associated with a higher risk of ASD. The risks ranged from 50% higher (for overall metals) to 100% higher (for diesel and mercury). For example, children with ASD were more than twice as likely to be born to mothers with the highest 20% of diesel and mercury exposure, than the lowest 20%.

However, due to its study design this research cannot, and does not, prove that higher air pollution around the time of childbirth causes or increases the risk of a child developing ASD. The causes of ASD are not firmly established and it is likely this research has not accounted for other factors that could be influencing risk. However, it does suggest a potential link that warrants further investigation.

Where did the story come from?

The study was led by researchers from the Harvard School of Public Health in the US and was funded by the US Department of Defence, Army Medical Research and Materiel Command, and National Institutes for Health.

The study was published in the peer-reviewed medical journal, Environmental Health Perspectives.

Neither the Daily Mail nor the Daily Mirror’s coverage discussed the limitations of the research and generally took the findings at face value. However, The Times’ coverage included points from ‘other scientists’ outlining some of the study’s limitations.

What kind of research was this?

This was a case-control study exploring whether exposure to pollution around the time of a child’s birth was linked to the risk of the child developing autism spectrum disorder.

Autistic spectrum disorders (ASDs) cover a range of related developmental disorders, including autism and Asperger’s syndrome. They have key characteristics, including problems with:

• social interaction with others (such as not being able to respond to others’ emotions)
• communication (such as difficulties in having a conversation)
• having a restricted, repetitive collection of interests and activities, rigid routine or rituals

Children described with autism usually have some degree of intellectual impairment and learning difficulties, while children with Asperger’s usually have normal intelligence.

The researchers describe how air pollution contains many toxic chemicals known to affect neurological function and foetal development. Recent studies have reported associations between exposure to air pollutants around the time of childbirth and ASD in children. This study sought to explore this link further.

What did the research involve?

This study involved asking a group of mothers if their children had ASD and then assigning historical pollution data to their address around the time the child was born.

This study used data from the Nurses’ Health Study II, a cohort of 116,430 female nurses from 14 US states. The Nurses’ Health Study II cohort was established in 1989 and has been followed over time with biennial questionnaires.

In 2007-08, researchers sent a questionnaire to the 756 women who had previously reported having a child with ASD, asking about the affected child’s sex, birth date, and whether they were adopted. These represented the “cases” in this study. They were also asked what specific diagnosis the child had been given with autism, Asperger syndrome, and ‘pervasive developmental disorder not otherwise specified’ (PDD-NOS) as possible answers. Cases were excluded if:

• they had missing data for ASD diagnosis
• they were adopted
• the mother did not want to participate
• the child’s year of birth was missing

This yielded 325 cases that were included in the final analysis.

The ASD diagnoses were validated by telephone using a questionnaire called the Autism Diagnostic Interview Revised. The researchers used 50 randomly selected “case” mothers who indicated willingness to complete the interview.

A group of 22,098 “controls” were used as a comparison group. These were children born from 1987 to 2002 (the years when air pollution data were available) to mothers who indicated they had never had a child with ASD.

Hazardous air pollutant concentrations were assessed by the US Environmental Protection Agency (EPA) National Air Toxics Assessments in 1990, 1996, 1999, and 2002. These used an inventory of outdoor sources of air pollution, including both stationary sources (such as waste incinerators and small businesses) and mobile sources (such as traffic) to estimate average concentrations of pollutants for different communities based on pollution dispersion models.

As pollution levels were not measured every year, the children were assigned pollution concentrations from EPA assessments closest to their year of birth (births 1987 to 1993 used 1990 concentrations; births 1994 to 1997 used 1996 concentrations; births 1998 to 2000 used 1999 concentrations and births 2001 to 2002 used 2002 concentrations).

The researchers recorded family (including grandparents’ education level) and community socioeconomic factors (average community income and education level) that could potentially influence the risk of ASD. They attempted to compensate for these influences in the statistical analysis.

What were the basic results?

The final analysis compared information from 325 cases, with 22,101 controls.

The researchers categorised the children’s level of pollution exposure into fifths (20% of the study group in each pollution level category). They found that those children exposed to the highest versus lowest fifth of diesel, lead, manganese, mercury, methylene chloride, and an overall measure of metals were significantly more likely to have an ASD. The odds ratios for these exposures ranged from 1.5 (for overall metals measure) to 2.0 (for diesel and mercury). This means those in the highest fifth (the top 20%) of diesel and mercury exposure were found to be twice as likely to develop ASD compared with those in the lowest fifth (the bottom 20%).

When the researchers looked at the linear trends, these were also positive and statistically significant for these exposures. This means the risk went up directly as pollution levels went up.

For most pollutants, associations were stronger for boys (279 cases) than girls (46 cases) and were significantly different according to gender.

How did the researchers interpret the results?

The authors concluded that exposure to air pollutants around the time of child birth, “may increase risk of ASD”, and that future studies should investigate the gender differences observed.

Conclusion

The limitations in this study’s design mean it cannot prove that air pollution causes or increases the risk of developing autism spectrum disorder (ASD). However, it does tentatively suggest higher pollution levels may increase the risk, which may prompt further, more reliable investigation.

It is important to consider the limitations of this research before concluding a direct causal link between environmental pollutants and autistic spectrum disorders.

Problems with assessment of pollution levels

The air pollution data was not accurately assigned to the child’s date of birth. Some children were assigned pollution levels three years before they were born, and others three years after. This means we cannot be sure at which point (before or after child birth) pollution may be influencing the risk of ASD, or whether the timing of pollution exposure was important in any way.

This occurred because the researchers used existing pollution data and fitted this as best they could to the dates the children were born. While this was clearly a practical approach, as the dates didn’t match exactly, it will have introduced some inaccuracy. The researchers implied that exposure may be more important before birth as some pollutants can affect the developing baby.

Difficulty specifying causes of autistic spectrum disorders

The possible causes of ASD are not firmly established. While some effort was made to adjust for additional factors that could affect ASD risk outside of pollution, this may not have been complete. Hence, differences in factors such as socioeconomic circumstances (as well as others) may account for some or all of the differences in ASD risk observed.

Problems with comparing risks for boys versus girls

There were very few girls in the study, most likely because ASD is more common in boys than girls. The small number of girls make reliable comparisons between boys and girls difficult. As the researchers point out, for this reason, the conclusions around differences in risk versus exposure profiles between boys and girls are not reliable.

Small number of cases included

The sample size of children with ASD was quite small (325) in this study and represented less than half of the original 756 eligible for the study. Many participants were excluded because they had important information missing such as the year of birth. This small sample may not be representative of the wider group of children with ASD.

The bottom line is that this study does not prove that air pollution increases the risk of a child developing ASD. However, it does highlight a potential link that warrants further investigation.

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

Links To The Headlines

Autism twice as likely in babies if mum lives near busy road, study claims. Daily Mirror. June 19 2013

Risk of autism is up to 50% higher in children exposed to traffic fumes and air pollution. Daily Mail. June 19 2013

Severe air pollution ‘can double risk of having autistic child’. The Times. June 19 2013

Links To Science

Roberts AL, et al. Perinatal Air Pollutant Exposures and Autism Spectrum Disorder in the Children of Nurses’ Health Study II Participants. Environmental Health Perspectives. Published online June 18 2013

A radical overhaul of how nutritional information is displayed on the front of the packaging of many food products has been announced.

The government, food makers and food retailers have agreed the new standardised front-of-pack labelling to help make it easier for people to make healthier choices about what they buy and eat.

The Department of Health has today set out what the new food labels will look like and outlined how a colour-coding scheme of energy, salt, sugar and fat will look and how their levels are set.

Currently, food and drink labels often differ in the range of nutritional information provided. Currently, there is no law forcing retailers and manufacturers to display such information and manufacturers are currently only required by law to provide nutritional information if the product makes a nutritional claim. For instance, nutritional information must be on a product that claims to be ‘low fat’ or if vitamins or minerals have been added to the product.

Under new European Union rules, manufacturers will be required to provide particular nutritional information by December 2016. But any manufacturer that chooses to provide front-of-pack information will have to comply with the EU regulation by the end of 2014.

The new style of labels will follow the same format as this example from a packet of breakfast cereal:

What changes are being made to food labels?

Nutrition labels, when they are displayed, are often provided on the back, side or on the front of packaging. The new, standardised food labels will be displayed on the front of food and drink products and they will routinely include the following information per portion of food:

• the amount of energy (presented in kilojoules (kJ) and kilocalories (kcal), known as calories)
• the amount of fat and saturated fat
• the amount of sugar
• the amount of salt

These amounts will be shown as ‘Reference Intakes’ (formerly known as ‘Guideline Daily Amounts’). Alongside the amounts listed above, food labels will show how much of the maximum daily intake a portion of food accounts for.

Food labels will also contain red, amber and green colour-coding to visually show the nutritional value of food portions. This will allow people to see at a glance if the food product has high, medium or low amounts of fat, saturated fat, sugars and salt:

• red means high
• amber means medium
• green means low

In short, the more green lights, the healthier the choice.

Read more about the terms used on food labels.

When are these changes being made?

Standardised front-of-label packaging will be in place by December 2014 by organisations that have signed up to make the changes. Some have already made the changes and some will make changes from today.

Why are food labels being changed?

Research has shown that the different nutrition labels on food are confusing. These different nutrition labels have arisen because companies have responded to their customers’ demand for more nutritional information, but until now there has been no agreement on a consistent format. The new labelling system aims to make it easier for people to make healthier choices, by comparing the same kinds of foods to see if there is a healthier option. 

As part of the government’s efforts to improve health through reducing obesity levels, the Department of Health is working with food manufacturers and supermarkets through a programme called the Responsibility Deal. This programme aims to get business to reduce the amount of calories, salt and saturated fat in foods. The standardised front-of-pack label is a new Responsibility Deal pledge that food and drink companies can sign up to. Many companies already have taken this pledge to change their food labels.

Public Health Minister, Anna Soubry, said: “The UK already has the largest number of products using a front-of-pack label in Europe, but we know that people get confused by the variety of labels that are used. Research shows that, of all the current schemes, people like this label the most and they can use the information to make healthier choices.

“We all have a responsibility to tackle the challenge of obesity, including the food industry. By having all major retailers and manufacturers signed up to the consistent label, we will all be able to see at a glance what is in our food – this is why I want to see more manufacturers signing up and using the label.” 

The labels are not designed to ‘demonise’ foods with lots of reds, but to have people consider what they are eating and make sure it’s part of a balanced diet. Download the eatwell plate (PDF, 1.6Mb) for more information about a healthy balanced diet.

Links To The Headlines

Food packaging 'traffic lights' to signal healthy choices on salt, fat and sugar. The Guardian, June 19 2013

New food labelling system launched. The Daily Telegraph, June 19 2013

Traffic light food labelling introduced by big supermarkets. Daily Mirror, June 19 2013

Food labelling: Consistent system to be rolled out. BBC News, June 19 2013

Major UK Supermarkets Launch New Food Labels. Sky News, June 19 2013

Red labels to warn of unhealthy food: Logos to appear on items considered 'bad' for health in anti-obesity drive. Daily Mail, June 19 2013

Rarely a month goes by without the papers reporting at least one health news story related to vitamin D. In recent weeks the media has reported that vitamin D can help relieve the symptoms of asthma and lower blood pressure.

There have been long-standing claims that vitamin D brings a wide range of benefits, from preventing cancer risk to improving mental health, or even reducing your risk of getting multiple sclerosis.

But is there good evidence to back up the claims? And do you need to change your diet or take vitamin D supplements to reduce your risk of disease?

What is vitamin D?

Vitamin D is a group of related molecules that the body needs to help absorb calcium and phosphate. These are substances that help keep the bones healthy and strong.

Vitamin D is somewhat unusual in that we obtain it from two difference sources:

• sunlight
• dietary sources

How much sun is needed to get enough vitamin D?

When the skin is exposed to the ultraviolet B contained in sunlight, it generates the production of vitamin D. Most people generate around 90% of the vitamin D in their body from sunlight.

Your sunshine requirements differ depending on factors such as your skin tone and your weight. A 2010 consensus statement on vitamin D (PDF, 126.69kb), released by a combination of charities, recommended a "little and often" approach. It says regularly going out with sunscreen for a few minutes in the middle of the day should provide enough exposure to create sufficient vitamin D.

You certainly don't need to get a suntan, let alone risk sunburn. Overexposure to the sun in this way can increase your risk of skin cancer.

How to get enough vitamin D through your diet

Eating a healthy balanced diet should be sufficient to top up the remaining 10% or so that experts believe we need through our diet. Dietary sources of vitamin D include:

• oily fish, such as salmon, sardines and mackerel
• eggs
• fortified fat spreads
• fortified breakfast cereals
• powdered milk

What is vitamin D deficiency?

Vitamin D deficiency is when the body does not have enough vitamin D to properly absorb the required levels of calcium and phosphate.

Mild to moderate vitamin D deficiency can lead to bone pain and weakening of the bones (osteoporosis). This could make you more likely to fracture a bone if you had a fall.

More severe levels of deficiency can lead to the development of rickets in children and osteomalacia in adults.

Rickets, osteomalacia and vitamin D

Chronic severe vitamin D deficiency in children can disrupt the normal formation of bones, causing them to become soft and malformed and resulting in the condition known as rickets.

Symptoms of rickets include:

• bone pain
• deformities
• fragile bones vulnerable to fracture

Previously regarded as a disease of the past associated with Victorian slums, rickets is now making a comeback in some parts of England.

In 2012 the Royal College of Paediatrics and Child Health released a statement highlighting the problems of vitamin D deficiency in children, reporting that rates of rickets have risen fourfold in the last 15 years.

Osteomalacia, like rickets, develops because of softening of the bones. The main symptom of osteomalacia is a dull, throbbing and often severe bone pain that usually affects the lower section of the body. Osteomalacia can also result in muscle weakness.

Other health risks that have been linked with vitamin D deficiency

In a 2010 BMJ clinical review on vitamin D deficiency, researchers presented evidence that vitamin D deficiency may increase the risk of developing a number of chronic conditions, such as:

• heart disease
• bowel cancer
• breast cancer
• multiple sclerosis 
• diabetes

However, more research is required to prove these associations and provide evidence that people need to change their behaviour or take supplements because of potential health problems.

How common is vitamin D deficiency?

Vitamin D is thought to be much more common than most people realise. A 2007 survey estimated that around 50% of all adults have some degree of vitamin D deficiency.

In 2012 the Chief Medical Officer for the United Kingdom wrote to GPs highlighting the issue of vitamin D deficiency in high-risk groups (see below).

An independent advisory committee is also reviewing current recommendations on vitamin D, but the results of this extensive analysis are not expected until 2014.

What are the risk factors for vitamin D deficiency?

Lack of exposure to sunlight

Unsurprisingly, a significant risk factor for vitamin D deficiency is lack of exposure to the sun.

Possible factors that can result in limited exposure to sunlight include:

• overuse of sunblock
• being housebound or spending long parts of the day inside
• wearing clothes that cover up most of your body, often for cultural or religious regions

There are anecdotal reports that children may be more likely to develop vitamin D deficiency these days, as they are less likely to play outside than children did in the past.

Darker skin tone

Having a darker skin tone means you require a greater amount of sunlight exposure to generate vitamin D.

It is estimated that people with a naturally dark skin tone may require three to five times longer sunlight exposure to make the same amount of vitamin D as a white person.

Obesity

Obesity could be an overlooked cause of vitamin D deficiency. A recent study published in February 2013 suggested there is a direct relationship between increasing body mass index (BMI) and falling vitamin D levels.

The authors of the study speculated that vitamin D may become "trapped" inside fat tissue, so there is less available to circulate inside the blood.

How is vitamin D deficiency treated?

Mild to moderate vitamin D deficiency can usually be treated by making lifestyle changes such as getting more sun and eating foods rich in vitamin D. In some cases your GP may also recommend you take vitamin D supplements.

In more severe cases where the deficiency has affected bone growth and density, such as rickets, a vitamin D injection may be recommended.

Foods fortified with vitamin D

Unlike in some other countries, in England staple food items such as milk, flour and cereals are not routinely fortified with vitamin D. Fortified versions of goods such as cereals and milk are available from most supermarkets. You can read the food labels to compare the levels of vitamin D between products.

Some argue that people in the UK, especially in the north of England and Scotland, would benefit from fortification. However, the vitamin D we get from dietary sources is thought to stay in the body longer than the vitamin D we get from sunlight. Fortifying staple foods and drinks could potentially lead to dangerously high levels of vitamin D in a small number of people (vitamin D toxicity).

Other benefits of vitamin D

Links To Science

Avenell A et al. Vitamin D and vitamin D analogues for preventing fractures associated with involutional and post-menopausal osteoporosis. Cochrane Database of Systematic Reviews. April 2009

Bjelakovic G et al. Vitamin D supplementation for prevention of mortality in adults. Cochrane Database of Systematic Reviews. July 2011

Garland CF et al. Vitamin D for Cancer Prevention: Global Perspective. Annals of Epidemiology. July 2009

Holick MF et al. Evaluation, Treatment, and Prevention of Vitamin D Deficiency: an Endocrine Society Clinical Practice Guideline. Journal of Clinical Endocrinology and Metabolism. July 2011

Jagannath VA et al. Vitamin D for the management of multiple sclerosis. Cochrane Database of Systematic Reviews. December 2010

Pearce SH, Cheetham TD. Diagnosis and management of vitamin D deficiency. BMJ. January 2010

Urashima M et al. Randomized trial of vitamin D supplementation to prevent seasonal influenza A in schoolchildren. American Journal of Clinical Nutrition. March 2010

Vimaleswaran KS et al. Causal Relationship between Obesity and Vitamin D Status: Bi-Directional Mendelian Randomization Analysis of Multiple Cohorts. PLOS Medicine. Published online February 5 2013

“A glass of wine every day in pregnancy could be good for your baby,” is the entirely incorrect headline in The Daily Telegraph today. Other newspapers reported that drinking while pregnant does ‘no harm’, these claims are also misleading.

The news is based on a new study investigating the link between alcohol exposure before birth and childhood balance, which is considered an important sign of children’s development. Previous research has found that alcohol consumption during pregnancy is linked to poorer outcomes on several markers of neurodevelopment, but the effect on balance is uncertain.

Researchers found no evidence of an adverse effect of low-to-moderate maternal alcohol consumption on childhood balance. They also found moderate alcohol exposure seemed to have a beneficial effect compared to no alcohol. However, the researchers say that this positive effect is possibly due to them not being able to fully adjust for the fact that higher alcohol use was linked to social advantage.

This study adds to knowledge about the effects of alcohol in pregnancy on children’s balance. However, uncertainty remains over whether there is a ‘safe’ level of alcohol consumption during pregnancy. For this reason, current guidance suggests that women avoid alcohol completely during the first three months of pregnancy. If women choose to drink after this time, they should not drink more than one to two units of alcohol once or twice per week, and avoid binge drinking altogether. Contrary to media suggestions, this study does not change this advice.

Where did the story come from?

The study was carried out by researchers from the University of Bristol and University Hospital Bristol NHS Foundation Trust and was funded by the UK Medical Research Council, the Wellcome Trust, the University of Bristol and the Alcohol Education and Research Council (AERC). The study was published in the peer-reviewed, open access medical journal, BMJ Open.

The Telegraph’s headline was incorrect and potentially dangerous. While the researchers found a positive effect of alcohol in one measure, they clearly and categorically said that this likely to be a statistical blip. This headline also ignores the fact that the research was into just one aspect of children’s development and that alcohol consumption was measured at only one point in time.

Because of these limitations, women should stick to the existing advice on alcohol in pregnancy. Fortunately, in its online edition, the Telegraph used a more accurate headline. All other newspapers’ headlines suggested that drinking in pregnancy was “OK”, or does “no harm” – and are also misleading.

What kind of research was this?

This was a prospective cohort study that aimed to determine whether there was a link between alcohol exposure during pregnancy and balance in 10-year old children. Although this is the ideal study design to address this question, cohort studies can only show association, and cannot prove a cause-and-effect relationship. This is because other factors (confounders) may be responsible for any association seen.

This problem is demonstrated by this study. Despite the fact that the researchers collected information on a number of socioeconomic factors, and adjusted for them in their analyses, they conclude that the associations seen are probably due to not fully being able to adjust for social advantage.

What did the research involve?

The researchers used information on 6,915 children and their parents, who were participating in the Avon Longitudinal Study of Parents and Children.

This study used children who were born singly (who were not twins or another multiple birth) between April 1991 and December 1992, who had undergone balance assessment at 10 years of age and for whom they had information on the mother’s alcohol intake.

The balance assessment evaluated three types of balance:

• dynamic balance: time to cross a 2m balance beam, walking heel to toe 
• static balance, eyes open: heel to toe balance on a beam, eyes open and standing on one leg, eyes open. Both balances were held for a maximum of 20 seconds
• static balance, eyes closed: heel to toe balance on a beam, eyes closed and standing on one leg, eyes closed. Both balances were held for a maximum of 20 seconds

Children were said to have ‘good balance’ if they were in the top 25% fastest times for crossing the balance beam (good dynamic balance), if they maintained the static balances with their eyes open for 20 seconds (good static balance with eyes open), and if they were in the top 25% longest times for holding the static balances with eyes closed (good static balance with eyes closed).

Alcohol exposure was measured by asking mothers and fathers to self-report their alcohol intake at 18 weeks of pregnancy.

At 18 weeks of pregnancy, mothers reported both their current consumption and their consumption prior to pregnancy. For each time point, the mothers reported the total number of glasses (defined as a pub measure of spirits, half a pint of larger or cider, a small glass of wine) consumed per week, categorised into none (0 glasses), low (1-2 glasses), moderate (3-7 glasses), and high (more than 7 glasses) consumption. Mothers were also asked how many days in the previous month they had drunk the equivalent of at least four units of alcohol (binge drinking). Similarly, fathers reported alcohol consumption and binge drinking.

Information on other factors that could explain any association seen (confounders) was also collected. These included marital status, crowding index (number of people in the household and number of rooms), home ownership, parity (the number of previous children the mother has), maternal education, ethnicity, maternal age, maternal social class, smoking, cannabis use, caffeine consumption, number of stressful maternal life events during pregnancy, and maternal depression.

The researchers looked to see whether there was a link between alcohol exposure during pregnancy and the balance ability of 10-year old children after adjusting for these potential confounders.

What were the basic results?

Few mothers reported drinking heavily during pregnancy, with 95.5% of mothers reporting no alcohol consumption to moderate alcohol consumption.

In general, higher total levels of maternal alcohol consumption were associated with higher socioeconomic status and higher maternal age, whereas higher levels of binge drinking were associated with lower socioeconomic status and lower maternal age.

No evidence was found of an adverse effect of maternal alcohol consumption on childhood balance.

• There was no association between any level of alcohol consumption during pregnancy and childhood dynamic balance.
• Compared to no alcohol consumption at 18 weeks of pregnancy, moderate maternal alcohol consumption was significantly associated with good static balance with both eyes open and eyes closed.
• There was no significant difference in static balance (eyes open or eyes closed) between no alcohol, low alcohol or high alcohol (the only significant association seen was for moderate alcohol).

Regular heavy maternal binge drinking (more than 10 times per month) was also associated with good static balance (eyes shut) in children. There was no significant association between any other level of binge drinking, or any other measure of balance.

Paternal drinking during the first three months was associated with good static balance (eyes open) in children, with fathers that reported drinking less than one glass per week, at least one glass per week and at least one glass per day having children with better static balance than those that reported never drinking.

The researchers then analysed the data differently, using a technique called “Mendelian randomisation”. This approach is based on the assumption that a person’s DNA is not linked to socioeconomic status.

It is known from previous research that particular variations in a gene that codes for alcohol dehydrogenase (an enzyme that breaks down alcohol) predisposes people to lower alcohol consumption. The researchers looked at this variant. Mothers carrying this variant consumed less alcohol before, during and after pregnancy.

There was no evidence that mothers carrying this variant had children with poorer balance, which is not what would be expected if alcohol exposure improves balance. The researchers use this result to suggest that the previous association between maternal alcohol consumption and balance outcomes may have been due to the fact that the current analysis could not completely adjust for socioeconomic status.

How did the researchers interpret the results?

The researchers suggest that the most correct interpretation of their results is that they, “provide no strong evidence of an effect, either beneficial or detrimental, of moderate maternal alcohol use during pregnancy on offspring balance.”

Conclusion

This large, well-designed prospective study has found no evidence that moderate maternal alcohol consumption at 18 weeks of pregnancy has an adverse effect on offspring balance at age 10.

The study is limited by the fact that, as a cohort study, it cannot show a cause-and-effect relationship. This is because other confounding factors may be responsible for any association seen.

Despite the fact that the researchers collected information on a number of socioeconomic factors, and adjusted for them in their analyses, they conclude that the small benefits seen for some outcomes with some drinking patterns are probably due to not fully being able to adjust for social advantage.

Also, maternal and paternal alcohol use was self-reported and alcohol use during pregnancy was assessed at only one point in time, which could be subject to bias. The researchers also reported that the balance measures used had low test-retest reliability.

Although the results of this study will add to knowledge about the effects of alcohol in pregnancy on one particular developmental outcome, uncertainty remains over what is a ‘safe’ level of alcohol consumption during pregnancy.

Current guidance suggests that women avoid alcohol completely during the first three months of pregnancy due to increased risk of miscarriage, and if they choose to drink after this time, should not drink more than one to two units of alcohol once or twice per week, and avoid binge drinking altogether. This study does not change this advice.

For more advice, read Can I drink alcohol when pregnant.

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

Links To The Headlines

A glass of wine a day in pregnancy could be good for your baby. The Daily Telegraph. June 18 2013

Moderate drinking during pregnancy 'does not harm baby's development'. The Guardian. June 18 2013

Pregnant women told moderate drinking will not harm the baby. The Independent. June 18 2013

Mums-to-be 'CAN have a glass of wine a day without harming their child's development'. Daily Mail. June 18 2013

Glass of wine per day OK during pregnancy, study claims. Daily Mirror. June 18 2013

Glass of wine does no physical harm, pregnant women told. The Times. June 18 2013

Links To Science

Humphriss R, et al. Prenatal alcohol exposure and childhood balance ability: findings from a UK birth cohort study. BMJ Open. Published online June 18 2013

"Women with a family history of breast cancer should be screened in their thirties," says The Daily Telegraph.

The news relates to an ongoing study that aims to look at the effects of mammography screening in women with a family history of breast cancer when they are between the ages of 35 and 39. 

National guidelines currently recommend that women identified as being at increased risk of breast cancer because of a family history of the disease are offered annual mammography screening from the age of 40. Women at very high risk, such as those with BRCA1 or 2 mutations, are already offered annual MRI screening from the age of 30.

This report covers the first stage of the study, which looked back at the type of screening offered to women in this category at 33 centres across the UK. It found that the majority of the centres surveyed offered mammography, with most offering it on an annual basis.

In the five centres with the most rigorous follow-up, 47 cancers were identified in women, with almost half identified through screening and about a third identified between mammograms.

Comparison of these cancers with results reported in previous studies in unscreened women suggested that in the women offered screening, the cancers identified were smaller and less likely to have spread to the lymph nodes at the time of diagnosis.

The current study gives a snapshot of existing surveillance measures in the UK for women aged 35-39 who have an increased risk of breast cancer because of their family history. But as the centres surveyed were not specifically collecting information in order to analyse the effectiveness of mammography screening, they did not have enough information for a thorough analysis.

Therefore, the second part of this study plans to follow 2,800 high-risk women offered mammography screening on an annual basis up to 2016. These results will give a better idea of the potential benefits, risks and costs of screening in this younger age group.

Where did the story come from?

The study was carried out by researchers from the Genesis Breast Cancer Prevention Centre at the University Hospital of South Manchester NHS Trust and other hospitals and research centres in the UK.

It was funded by Breast Cancer Campaign and was published in the peer-reviewed medical journal, Familial Cancer.

The Daily Telegraph's headline doesn't convey the preliminary nature of these findings, but it does report later on in the story that a larger study is planned and that changes to recommendations are only likely if the larger study confirms the results.

What kind of research was this?

The researchers were reporting on part of a study of breast cancer screening in younger women with a family history of breast cancer (the FH02 study). The first part of the study was a retrospective analysis of the type of breast cancer surveillance that has been offered to these women in the past and what their outcomes were.

In the UK, all women between the ages of 50 and 70 are currently offered mammography. Women whose family history indicates that they are at increased risk are offered annual mammograms from the age of 40 as a form of "surveillance" for the disease. Women at very high risk, including those who are known to carry mutations in one of the BRCA1/BRCA2/TP53 genes, are offered annual MRI screening from the age of 30.

The researchers report that a previous study looked at mammography for women aged 40-49 in the UK with a significant family history of the disease (the FH01 study), but the effects of mammography in women aged 35-39 has not yet been assessed.

The National Institute for Health and Care Excellence (NICE) has produced guidelines on how doctors should classify breast cancer risk in women with a family history of the disease, and how they should be assessed and treated.

The researchers state that in the second part of this study, they will carry out a prospective study to look at the effects of breast cancer surveillance in these younger women. A previous study suggested that the health professionals caring for these women feel that such surveillance is likely to be of benefit. For this reason, it was decided that it would not be ethical to carry out a randomised controlled trial and that the study would compare the participants' results with those from previous studies instead.

What did the research involve?

Retrospective study

The researchers sent a survey to the 33 centres taking part in the study. The survey asked whether they had previously carried out mammographic surveillance in women under the age of 40 with an increased familial risk of breast cancer.

If they answered yes, the survey then asked about exactly how they selected women for surveillance and what this consisted of. They also asked about the outcomes of this surveillance, including the number and type of cancers identified.

The researchers compared these results with the types of cancer reported in studies published previously looking at women:

• aged 40-49 years with a family history of breast cancer who had annual mammography (the FH01 study)
• aged 40-49 years with a family history of breast cancer
• a series of women aged 30-49 having breast cancer surgery
• women aged 35-39 years with a family history of breast cancer who had not been screened

Prospective study

The researchers reported in detail the planned approach for their prospective study. This study aims to identify the likely benefit of annual mammography for women aged 35-39 with a family history of breast cancer.

They will compare the results in this group with results from the preceding study in older women with a family history of the disease (the FH01 study) and the UK Age Trial, a randomised controlled trial that assessed the effects of annual mammography screening in women from the age of 40 (not selected on the basis of family history). This study will also assess the cost of surveillance, so it can estimate its cost effectiveness.

The researchers say they have recruited 2,280 women from 33 centres, and should have reached the target of 2,800 by the end of June 2013. The study is expected to continue until June 2016.

What were the basic results?

In their survey, the researchers found that among the 33 centres:

• mammography screening in women aged 35-39 at increased risk of breast cancer was already carried out in 27 centres
• almost all of this screening was reported to use film mammography, rather than the newer digital mammography
• these 27 centres record a three generation family history and carry out a risk assessment in these women to determine their risk level
• 25 of the centres record the women's lifetime risk of cancer and 22 record whether they have the known genetic mutations which predispose women to breast cancer (BRCA1, BRCA 2 and TP53)
• 26 of the centres offered the women annual mammograms and one centre offered them screening every two years
• 17 centres offered MRI scanning
• 14 centres offered routine physical examinations
• none of the centres routinely offered ultrasound

Five centres had robust systems to reliably identify whether any breast cancers were identified in these women in the period between mammograms (called interval cancers), as well as any detected in the mammogram.

There were 47 breast cancers in the women attending these centres between 1994 and 2010. Ten of these cancers (21%) were already known when the women attended the centres, 22 were new cancers (47%) identified through screening, and 15 (32%) were detected between mammograms.

Compared with two groups of unscreened women with breast cancer – one who had a similar family history and one without a family history – the cancers among the screened women were significantly smaller and less likely to have spread to the lymph nodes.

More of the screened women were alive with no spread of the disease in the screened group than in the two groups of unscreened women with breast cancer. However, the number of deaths from breast cancer was too small to carry out a robust analysis.

How did the researchers interpret the results?

The researchers say that this is the first study to assess the effects of mammography alone in women aged under 40 who are at increased risk of breast cancer.

They say that the results are "encouraging", but that the prospective part of their study is needed to assess the effects of digital mammography in moderate and high-risk women in order to inform cost effectiveness analyses.

Conclusion

The current study gives a snapshot of existing surveillance measures in the UK for women aged 35 to 39 with an increased risk of breast cancer due to their family history.

There are some points to note, which the authors themselves highlight:

• As this first part of the study is retrospective, the centres will not have collected all the relevant information that would allow thorough evaluation of the effects of mammography.
• The number of cancers in women receiving screening described in detail in the current study is small (just 47). The larger prospective part of the study is needed to get better estimates of the rates of cancer in these women.
• Most previous screening in the centres used film mammography, but the newer technique of digital mammography may offer better results. 
• In addition, the comparisons performed in the current part of the study against results in other studies may be affected by differences between the groups of women other than the screening offered. For example, the studies covered different time periods, and breast cancer management may have differed over these periods and could affect the chances of survival.

Overall, the current study gives some background information, but the second part of the study will shed more light on the potential effects of mammography surveillance in younger women at increased risk of breast cancer.
 

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

Links To The Headlines

Family history of breast cancer should mean screening earlier. The Daily Telegraph, June 17 2013

'Screen women aged 30 for breast cancer': Half a million at risk because of family history could be offered mammograms. Daily Mail, June 17 2013

Call for more breast cancer screening. The Times website, June 17 2013

Links To Science

Evans DG et al. Mammographic surveillance in women aged 35–39 at enhanced familial risk of breast cancer (FH02). Familial Cancer. Published online June 4 2013

“Anti-baldness drug can cause men to lose interest in alcohol,” reports the Mail Online.

This report is based on a small survey of young men who had been taking the drug, finasteride, for hair loss. Impotence and decreased libido are recognised side effects of this anti-male-hormone drug, and all 83 men in this study had experienced sexual side effects that lasted at least three months after they stopped taking it.

The survey found that the men reported drinking less at the time of the survey than before they started taking the drug. However, this was on average five years earlier, so it is not clear how well these men could remember what they drank so far in the past.

Also, as the study had no control group who didn’t take the drug, it’s not possible to say that these changes wouldn’t have happened naturally over time as the men aged. The results may also not be representative of what might be seen in older men, men taking the drug for its other use (enlarged prostate), or men who do not experience the sexual side effects of the drug.

Overall, these findings are inconclusive. Larger studies, ideally with a control group, are needed to assess the effects of the drug on alcohol consumption.

Where did the story come from?

The study was carried out by a single researcher from The George Washington University in the US. No sources of funding were reported. It was published in the peer-reviewed journal Alcoholism: Clinical and Experimental Research.

The Mail Online reports the results of the study, but not any of its fairly extensive limitations.

What kind of research was this?

This was a cross-sectional study reporting on the alcohol consumption among men taking the drug finasteride. This anti-male-hormone drug is licensed to treat benign (non-cancerous) enlargement of the prostate and male pattern hair loss.

The recognised side effects of the drug include sexual problems such as decreased libido, impotence and erectile dysfunction. It may also have effects on the nervous system. The researchers reported that finasteride has been shown to reduce alcohol intake in male mice, but no studies have assessed this in humans.

This study relied on men reporting their own alcohol consumption before and after taking the drug in a single survey. This is likely to be less reliable as men may not accurately remember their consumption in the past. Asking the men to keep an alcohol diary before and after they started taking the drug would be a more reliable approach.

The study also didn’t include a comparison group not taking the drug. Therefore, the result cannot conclusively show that the drug itself is definitely causing a change in alcohol consumption.

What did the research involve?

The researchers surveyed the alcohol consumption habits in 83 men aged under 40, who had been taking finasteride to treat or prevent male pattern hair loss. These men had experienced persistent sexual side effects but were otherwise healthy.

The men were reported to be recruited from the author’s previous studies on persistent sexual side-effects of finasteride. These men had side-effects for at least three months despite stopping finasteride. Men who had sexual dysfunction before taking finasteride, had chronic medical conditions, current or past psychiatric conditions, or had taken psychiatric medication were excluded.

The survey asked about their average weekly alcohol consumption before they started taking finasteride, and at the time of the interview. A glass of wine, can of beer, or shot of hard liquor was considered a standard drink.

What were the basic results?

Sixty-three of the men reported drinking at least one alcoholic drink per week before starting finasteride. Among these men, at the time of the survey:

• 65% reported reduced alcohol consumption 
• 32% reported no change in their alcohol consumption
• 3% reported an increase in their alcohol consumption

On average, of the men who reported drinking alcohol, the average number of drinks per week reduced significantly – from 5.2 before finasteride to 2.0 after finasteride. As the men had stopped taking finasteride, they were not taking the drug at the time of assessment.

The authors reported that although they were not asked about this specifically, some men volunteered the information that they could not tolerate alcohol as well after starting to take finasteride. Eighteen men reported giving up alcohol entirely.

How did the researchers interpret the results?

The researchers concluded that among men who developed persistent sexual side effects from finasteride and stopped taking the drug, almost two-thirds reported reduced alcohol consumption.

Conclusion

This relatively small study in a very select group of men provides only limited evidence of the effects of finasteride on alcohol consumption in men. Its limitations include:

• The study didn’t include a comparison group not taking the drug. Therefore, the result cannot conclusively show that the drug itself is definitely causing a change in alcohol consumption, rather than the men just having changing alcohol tolerance as they got older.
• The study asked men to remember what their alcohol consumption was before taking the drug – on average about five years previously. This is likely to be less reliable as men may not accurately remember their consumption in the past. Asking the men to keep an alcohol diary before and after they started taking the drug would be a more reliable approach.
• The study only used a crude assessment of the number of drinks consumed, the size and alcohol content of these drinks may vary and this could affect comparison of before and after findings.
• The study did not say exactly how men were selected to take part, or whether they knew the purpose of the study. The men’s responses may have altered if they knew that finasteride may have an effect on alcohol consumption.
• The men all had persistent sexual dysfunction following taking finasteride for male pattern hair loss. The results may not apply to other men taking the drug, for example those without these side effects, or those taking it for an enlarged prostate.
• The author reported that many of the men in the study experienced depressive symptoms, and this may have affected their alcohol consumption.

As the author acknowledges, more research would be needed to determine the effects of finasteride on the nervous system and alcohol consumption.

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

Links To The Headlines

Anti-baldness drug can cause men to lose interest in alcohol. Mail Online. June 17 2013

Links To Science

Irwig MS. Decreased Alcohol Consumption Among Former Male Users of Finasteride with Persistent Sexual Side Effects: A Preliminary Report. Alcoholism: Clinical and Experimental Research. Published online June 13 2013

“'Cradle snatchers' cause menopause, says biologist,” is the bizarre headline in The Guardian today.

The menopause has always been a bit of an evolutionary puzzle. Evolution is about one thing only – reproducing genes. So why would genes that cause a woman to lose fertility halfway through her life survive?

Two main theories have been previously suggested:

• one theory suggests the menopause is a trade-off in increased fertility versus prolonged survival 
• the second theory is known as the “grandmother effect”, whereby older, post-menopausal women are no longer fertile so they can instead help out with raising their grandchildren

A new study has provided a third theory. Humans started off with prolonged fertility, but if men theoretically preferred mating with younger women there would be no pressure to weed out the mutations that cause infertility in later life. According to this theory, over time mutations affecting fertility in older women accumulate – leading to most, and then all, women experiencing menopause.

Researchers used a complicated computer model to run a number of evolutionary cycles and found that the model was consistent with their theory. But it’s not possible to say conclusively that this model accurately represents what has happened in human evolution, and other factors may contribute.

The findings are interesting but they have no direct health implications. Menopause – for whatever reason it may occur – is a natural part of human female life, to which no blame should be attached.

Where did the story come from?

The study was carried out by researchers from McMaster University, Ontario, Canada, and was funded by the Origins Institute and Shared Hierarchical Academic Research Computing Network at McMaster University, and the Natural Sciences and Engineering Research Council of Canada.

The study was published in the peer-reviewed open access scientific journal PLoS Computational Biology.

The media reporting of the theory is broadly accurate but it is just that, a theory. This complex computer modelling research can only suggest certain scenarios that could potentially explain the observations seen. It is not possible to say conclusively that these models do represent what truly happened.

Headlines that suggested men are “to blame for the menopause” are a bit silly. Evolutionary forces are not something anyone has any control over. Blaming men for the menopause is like blaming someone other hereditary conditions that have evolved in humans over time, say, sickle cell anaemia.

A number of the news sources carry a quote from another expert critical of the theory. Dr Maxwell Burton-Chellew, an evolutionary biologist in the department of zoology at the University of Oxford, was quoted as saying: “This [theory] is probably the wrong way round - the human male preference for younger females is likely to be because older females are less fertile.”

What kind of research was this?

This was a computer modelling study trying to determine why women undergo menopause.

As the authors note, survival beyond the menopause is a characteristic that appears almost unique to humans with only odd exceptions (such as whales, and chimps in captivity). Evolutionary theories suggest that natural selection should operate against living beyond reproductive age and it is not clear (theoretically) why women live beyond the menopause.

At least two possibilities have been put forward to explain this phenomenon: a trade-off favouring longer lifespan over reproduction in women (because giving birth when older may increase mortality risk); and that menopause increases the reproductive success of the woman’s offspring (that is, the “grandmother effect” of older women being able to assist their children in rearing their own children).

Other researchers have suggested that living beyond menopause could be down to an influence from males. They suggest that the fact that men remain fertile throughout their lifespan would prevent accumulation of lifespan-shortening mutations, allowing men and women to live longer. However, this does not explain why women undergo menopause.

The current research aimed to test the effect of male mating preference on the evolution of the menopause. In particular, they were interested in the effect a male mating preference for younger females would have.

What did the research involve?

The research involved a complex computer model that looked at the effect on a population of male lifelong fertility and of male mating preference on female fertility.

The researchers modelled a population of a fixed size, which initially had pre-set fertility and survival probabilities. Each individual started the model in one of 18 increasing age classes. Survival probability for each age group (determined by the number and type of mortality-causing mutations introduced) was assessed at five-year intervals.

The different computer models then introduced mutations into the population that separately affected mortality and fertility – mutations that affected fertility did not affect survival, and mutations that affected survival did not affect fertility.

This determined whether any individual in each age group died or went into the next age bracket. All individuals that reached the oldest age class (class 18) died in the model.

Deaths in the model were replaced by new births assigned to the first age category. The births were simulated by randomly selecting a male from the surviving male population, and a female from the surviving female population. Male and female fertility probabilities in the model were influenced by the number and type of fertility-affecting mutations that had been introduced into the population.

The researchers used their model to look at two scenarios.

First scenario

In their first scenario, men retained lifelong fertility, while women underwent menopause. In this scenario men did not have an age-specific mating preference. The researchers looked at the effect of introducing into the population theoretical genetic mutations that reduced lifespan but did not affect fertility.

Second scenario

In their second scenario, the researchers started out with men and women being fertile all their lives. They then introduced mutations that caused reducing fertility, and mutations that affected survival. They looked at the impact on this scenario of men having a preference for mating with younger females.

What were the basic results?

In their first scenario – where men did not have an age-specific mating preference and women underwent menopause – the researchers found that if men retained lifelong fertility this did prevent
mortality-causing mutations from accumulating in females. However, this does not explain why menopause came about.

In their second scenario - where both sexes started with lifelong fertility and men preferred to mate with younger females – over time the mutations reducing female fertility with age accumulated in the population, causing a decline in female fertility with age; effectively the menopause. 

However, a similar effect was not seen if male mating preference was not influenced by women’s age.

How did the researchers interpret the results?

The researchers say that their model suggests that male mating preference for younger females could have driven the evolution of menopause. Their model did not need the presence of the other suggested explanations for the menopause to be present in order to work (the trade-off between fertility and lifespan and the “grandmother effect”). Instead they say that these explanations “may be insufficient factors in elucidating the origin of menopause”.

Conclusion

This computer modelling study has suggested that a male preference for mating with younger females could be the reason why menopause evolved in humans. However, whether this is truly the reason, or whether other factors some into play is not possible to say.

While this may be of interest to sociologists and others interested in the possibilities of human evolution, it has no direct health implications.

Unless someone comes up with a working time machine there is little we can do about the genetic cards that evolution has dealt us.

If you are experiencing the menopause, tempting as it may be to start blaming the men in your life, you are better off seeking support from your doctor, who may be able to offer treatment for particular symptoms of menopause.

A commonly used treatment is hormone replacement therapy (HRT), although there are also alternatives for women are not suited to HRT.

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

Links To The Headlines

'Cradle snatchers' cause menopause, says biologist. The Guardian, June 13 2013

Men 'to blame for the menopause'. BBC News, June 14 2013

Men may be to blame for the menopause. The Daily Telegraph, June 13 2013

Did man's yearning for young women create the menopause? Research suggests that men's wandering eyes may have caused middle-age loss of fertility in women. Mail Online, June 14 2013

Links To Science

Morton RA, Stone JR, Singh RS. Mate Choice and the Origin of Menopause. PLoS Computational Biology. Published online June 13 2013

“New AIDS prevention pill could cut infection rates in IV drug users by 50%,” the Mail Online reports, as the US Centers for Disease Control and Prevention (CDC) is set to approve the medication for injecting drug users.
 
The drug proved its worth in a large, well-conducted randomised control trial in Thailand. In this study, over 2,000 injecting drug users were given either placebo tablets or the ‘new’ drug tenofovir – which has been used to treat HIV since 2006.
 
The participants also attended monthly clinics to have blood tests to check for HIV infection, assess adverse events and to give them risk-reduction counselling. They were followed, on average, for four years to see if they contracted HIV.
 
The trial found that daily oral tenofovir reduced the drug users’ risk of catching HIV during the trial by about half: seven to eight per 1,000 would develop HIV per year without taking tenofovir, reducing to three to four per 1,000 per year if they did take tenofovir. Side effects for tenofovir were tolerable.
 
These are promising results though there are many other factors that would need to be considered before implementing an effective strategy on a wider scale outside of the context of a clinical trial.
 
While the obvious message in terms of HIV prevention is to stop injecting drugs, this type of pragmatic harm reduction approach could save many lives.

Where did the story come from?

The study was carried out by researchers from Bangkok Tenofovir Study Group, Bangkok, Thailand, and additional researchers from Centers for Disease Control and Prevention (CDC), Atlanta, and Johns Hopkins University, Baltimore, in the US. Funding was provided by the US CDC and Bangkok Metropolitan Administration.
 
The study was published in the peer-reviewed medical journal The Lancet.
 
The Mail Online's reporting of the study is accurate. However, there are additional issues that may need to be considered before the drug is licensed for this use, which the Mail does not describe.   

What kind of research was this?

This was a randomised controlled trial that aimed to assess whether daily use of the antiretroviral (anti-HIV) drug, tenofovir, could reduce HIV transmission in injecting drug users.
 
Injecting drug users are at high risk of getting HIV due to needle sharing. Tenofovir is currently licensed for the treatment of people who have HIV infection, usually taken in combination with other antiretrovirals.
 
The researchers suggest that use of antiretrovirals to prevent HIV infection could be ‘a promising new strategy to end the HIV/AIDS epidemic’. Previous studies in animals and humans have suggested the drugs can prevent transmission of the virus. They are currently used to reduce the risk of mother-to-child transmission of HIV, and to reduce risk among healthcare workers who may have been exposed to HIV (for example, through a ‘needlestick’ injury).
 
The current study is a phase III trial, meaning the research has already progressed through the earlier stages of clinical trials. This study investigated tenofovir's effects and safety compared with inactive placebo in a large sample of injecting drug users. 

What did the research involve?

The trial assessed whether giving tenofovir to injecting drug users reduced their chances of getting HIV over an average of four years.
 
It enrolled 2,413 injecting drug users from 17 drug-treatment clinics in Bangkok, Thailand. The clinics offer a wider range of services including HIV counselling and testing, risk-reduction counselling, social services, medical care, methadone treatment, condoms, and materials to clean injecting equipment (clinics cannot provide fresh needles under Thai law).
 
Participants were eligible if they were aged between 20 and 60 years, were HIV-negative, and reported injecting drugs during the previous year. The researchers excluded those positive for hepatitis B, and pregnant or breastfeeding women.
 
Participants were given contraception and hepatitis B vaccine, and were randomised to receive either daily oral tenofovir 300mg or identical placebo pills. Participants could choose either to be observed daily taking their treatment (this ensures the participants do actually take their pills), or could just attend the monthly visits. All participants attended monthly clinic visits where they received HIV blood testing, were assessed for adverse effects, and were counselled on risk-reduction and adherence to treatment.
 
Risk behaviour was assessed in more depth every three months.
 
The trial was long term, and lasted up to seven years. The average duration of follow-up was four years. The researchers assessed the number who remained in treatment each year. 

What were the basic results?

Of the 2,413 randomised participants, 80% were men, 43% were in their 20s, 38% were in their 30s, and the remainder were older. The majority (63%) had injected drugs within the past three months.
 
Drugs used included heroin (22%), methamphetamine (33%), midazolam – a sedative which can give feelings of euphoria if injected at high doses (23%), and 22% were currently in a methadone programme. 
 
For the first year, the proportion of participants retained in the trial was high (88% of the tenofovir group and 89% of the placebo group). However, this gradually declined each year up to seven years.
 
Overall, 34% of both groups withdrew from the study during the course of the seven years. Dropout during the course of the trial was for various reasons including loss to follow-up, death, pregnancy and contracting HIV. Participants took the drugs for an average 84% of treatment days, with no difference in adherence between the groups. Overall, 8% of participants reported sharing their drugs in some way.
 
HIV was acquired by 50 people during the trial:

• 17 in the tenofovir group – an incidence of 3.5 cases per 1,000 person-years of follow-up (if 1,000 people were followed for one year, three to four would develop HIV while taking tenofovir)
• 33 in the placebo group – an incidence of 6.8 per 1,000 person-years of follow-up (if 1,000 people who were not taking preventative treatment were followed for one year, six to eight would develop HIV)  

This meant that taking tenofovir cut the risk of contracting HIV by about half (48.9% reduction, 95% confidence interval [CI] 9.6 to 72.2%).
 
There was no significant difference in the risk of any adverse events between groups. The most frequent adverse events were:

• abdominal pain
• nausea
• vomiting
• weight loss
• diarrhoea
• rash
• fractures 

Between 5% and 20% of people in both groups experienced these events. The only event that was significantly more common with tenofovir was nausea and vomiting, which affected 8% of the tenofovir group and 5% of the placebo group. 

How did the researchers interpret the results?

The researchers concluded that daily oral tenofovir reduced the risk of HIV infection in people who inject drugs. They suggest that preventative treatment with tenofovir ‘can now be considered for use as part of an HIV prevention package for people who inject drugs’. 

Conclusion

This was a well-conducted trial which has many strengths, including its very large sample size, long duration of follow-up, and regular and thorough assessments of HIV outcomes, adherence to treatment, adverse effects and risk counselling.
 
It found that daily oral tenofovir, when taken by injecting drug users, causes an almost 50% reduction in their relative risk of contracting HIV. It found that about seven to eight per 1,000 would develop HIV per year without taking tenofovir, reducing to three to four per 1,000 per year if they did take tenofovir. 
 
Although the drug has been demonstrated to be effective, it is not yet licensed by drug regulators for this use. They will need to review a submission from the manufacturer on the evidence of efficacy and safety of the drug in injecting drug users before this can be granted. If tenofovir is licensed for this use, when considering whether it should be widely offered for this purpose, there are many factors to be taken into account. This includes the number of people that would need to be treated and duration of treatment, and the cost of this treatment. 
 
For injecting drug users there are other important considerations. This includes that injecting drug–users’ often chaotic lives mean that they can find it difficult to access health services and may only be in contact with health professionals sporadically. This trial included only those who were currently attending drug treatment clinics. However, there are likely to be many other vulnerable groups of injecting drug users in the community who are not attending clinics, or who attend but then are lost to follow-up. Therefore, ensuring that all drug users are able to access care, and receive continued care and treatment may be issues that would need to be considered.
 
Another potential concern, is that preventative HIV treatment could possibly give false reassurance that the person is fully protected and would not be harmed by practices such as sharing needles or other injecting equipment, or having unprotected sex. It would still be important to ensure that people receive full information and guidance on the risks of blood borne infections (and other sexually transmitted infections), and the need to follow safe practices such as using single use needles and equipment and using condoms.

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

Links To The Headlines

New AIDS prevention pill could cut infection rates in IV drug users by 50%. Mail Online, June 13 2013

Links To Science

Choopanya K, Martin M, Suntharasamai P, et al. Antiretroviral prophylaxis for HIV infection in injecting drug users in Bangkok, Thailand (the Bangkok Tenofovir Study): a randomised, double-blind, placebo-controlled phase 3 trial. The Lancet. Published online June 13 2013

“Lego characters are getting angrier – and could be harming children's development,” reports the Daily Mail.

Its report is based on a study that asked over 250 adults in the US to rate the emotion on the faces of more than 600 different Lego minifigures (affectionately known as "minifigs"). It found that most faces are happy, but that anger is also a common expression. Initially very different heads were produced, with the first face from 1975 being rated as sad, and the next few produced in the late 1970s and early 80s rated as happy.

Over time, the proportion of happy faces has declined. This increase has been partially driven by an increasing tendency towards cross-branding, such as Star Wars Lego, with some minifigs representing "baddies", rogues and warriors from these films.

Importantly, the study did not look at what impact the faces had on a child’s emotions. It is a great stretch to say that they may be “harming children’s development”.

You could also make the point that children actually enjoy an angry villain. Children’s fiction is full of infamous examples, ranging from Captain Hook to Voldemort.

A final piece of advice, provided by Lego, is that parents who are concerned “can always just switch heads with another figure”.

Where did the story come from?

The study was carried out by researchers from the Human Interface Technology Laboratory New Zealand at the University of Canterbury, and the Industrial Research Institute for Automation and Measurements in Poland. No sources of funding were reported.

The study appears to be a written summary of a presentation to be given at a scientific conference on how humans interact with objects that are designed to represent personalities. It is unclear whether the study has been peer-reviewed.

The media coverage has tended to overinterpret the findings of this research, with the lead researcher’s suggestion that angry faces could affect a child’s emotional development being accepted uncritically.

Also, The Guardian reports that “there were risks involved in exposing children to a variety of emotions, with small fans likely to remember the anger and fear in their figurines' faces, as well as their happier moments”. It is not clear how the paper came to include this statement, as the study did not assess children at all. In fact, only The Daily Telegraph explicitly reported in its text that the study only included adults.

The BBC News coverage includes a balancing comment from the author that it is "hard to derive a causal relationship" between angry toys and children's behaviours.

What kind of research was this?

This was a cross-sectional study looking at people’s perception of the emotion shown on Lego figures’ faces. The researchers were interested in whether the types of faces on Lego figures had changed over the last 35 years, and if perception of the face varies if the whole body of the figure is shown. The researchers are from a laboratory that looks at “developing and commercialising technology that improves human computer interaction”, with the ultimate goal of improving users’ experience.

Therefore, the study did not really focus on health issues or child development as such. It suggested that their study may help other researchers to understand the effect of the figures’ appearance on users over time, and also to inform design of other faces in game and toys.

What did the research involve?

The researchers took a sample of Lego figure faces over the years, and asked people what emotions the face expressed to see if the types of expression changed over time.

The researchers photographed all 3,655 Lego minifigures released between 1975 and 2010. They identified 628 heads with different faces used on these figures, and identified the year in which the head was first introduced. They used all of these faces in their study. They also randomly selected 100 heads and a minifigure with that head for use in their survey. They excluded six heads where the face was largely obscured, for example by a helmet. They also presented one figure (a Harry Potter figure) with two different skin colours – the traditional Lego yellow or a “natural” peach-coloured skin tone.

The researchers recruited 264 adults in the US through a website that enables people and businesses to ask other people to do tasks that computers are not capable of doing (called Human Intelligence Tasks).

They used the website to present the isolated faces and minifigures in a random order, with 30 people asked to rate each face. The participants were asked to rate which of these six emotions each face expressed:

• anger
• fear
• disgust
• happiness
• sadness
• surprise

They were asked to rank on a five-point scale (similar to a Likert scale) how intensely the face showed the emotion, ranging from “weak” to “intense”. The participants could rate as many of the faces as they liked and they were paid one cent per face they rated.

For each face, the researchers identified the dominant emotion for each face by finding which emotion was most commonly reported as being present. The researchers then looked at whether the figures’ faces had changed in the emotions shown over time. They also looked at whether presenting a face with the body of the figure changed perception of the face’s emotion.

What were the basic results?

The researchers found that each face was reported as expressing about four different emotions on average. The dominant emotion on most faces was happiness (324 faces) followed by anger (192 faces).

The number of different faces produced has increased over time, from fewer than five faces each year up to 1988, to more than 90 in 2010. From the early 1990s there was an increase in the variety of facial emotions shown by the minifigures. In 1975, the faces produced were all rated as sad, while in 1978 and 1980 all were rated as happy. However, in these years, only very few faces were produced. The proportion of happy faces released in each year decreased over time as more different and more varied faces were introduced.

If the figure’s body was shown as well as the face, anger tended to be reported more frequently, and disgust, sadness and surprise less frequently.

The minifigure’s skin colour did not affect which emotion was perceived on the face.

How did the researchers interpret the results?

The researchers concluded that “toy design has become a more complex design space in which the imaginary world of play does not only consist of a simple division of good versus evil, but a world in which heroes are scared and villains can have a superior smile”. They suggest that face designers should take care in designing the expressions and to test their effect “since toys play an important role in the development of children”. However, they also say that to appeal to users the faces need to offer a wide range of emotions “that connect to the complex interaction scenarios of today’s users”.

Conclusion

Overall, this research suggests that Lego figures’ faces have changed over time. This is a finding that is unlikely to surprise parents (or big kids of a certain age). The default minifig of old (described in the study as having an “enigmatic smile”) is now just part of a much larger family of minifigs including pirates, Star Wars “imperial stormtroopers” and ninjas.

So, as more faces have been produced it is unsurprising that a larger variety of emotions has been shown on the faces – particularly as minifigs now more commonly represent warriors. This study only assessed adults’ responses to the faces, and children’s perceptions of the faces may differ.

The study did not look at how children perceived the faces’ emotions or what impact the faces had on a person’s own emotions. The study doesn’t tell us anything about how the faces might potentially impact the health or development of children or adults playing with the figures. Therefore, it is a great stretch to say that they may be “harming children’s development” or are a “possible cause for concern”.

As the Lego manufacturer suggested in The Guardian, parents who might be concerned “can always just switch heads with another figure” (however, wary parents may want to consider the emotional effects of decapitating their children’s toys).

There are also studies suggesting that playing with Lego – or other toys designed to stimulate creativity, planning and building skills – can play a positive role in a child’s development.

Read more about why play is important.

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

Links To The Headlines

Lego faces are getting angrier, study finds. The Guardian, June 12 2013

Do Lego Minifigures' have anger-management issues? Toy's faces are becoming less cheerful and more grumpy, fearful and disdainful, finds study. Daily Mail, June 13 2013

Lego faces are angrier now, study shows. The Daily Telegraph, June 13 2013

Links To Science

Bartneck, C, Obaid, M, Zawieska, K Agents with faces – What can we learn from Lego Minifigures? (PDF 1.7Mb) Proceedings of the 1st International Conference on Human-Agent Interaction. 2013