“Parents will receive text message and email advice on how to bring up their children after David Cameron said it was ‘ludicrous’ that people get more training in driving a car,” the Daily Mail has reported.

The story, covered in much of the media, is based on the launch of a new interactive service providing information and advice to parents.

Why is this in the news?

Launched today by the prime minister David Cameron, the NHS Information Service for Parents gives mums, dads and parents-to-be advice on issues around staying healthy in pregnancy, preparing for birth and looking after their baby. It includes:

• advice via email and text messages (SMS)
• short film clips of advice from midwives and parents
• online advice from the NHS

Why has this service been launched?

The three initiatives are reportedly being launched because of the impact a child’s care early in life has on their health, behaviour and ability to learn throughout their lives. A 2010 Department for Education survey of 2,319 parents of under-threes, found that 85% wanted practical help with caring for their baby.

What can mums and dads and parents-to-be expect from the service?

The free Information Service for Parents emails and texts contain NHS-approved advice and will be sent every week from five weeks pregnant through to four weeks after the birth of your baby. Fathers-to-be can sign up for advice specifically aimed at them. The email and text service is expected to offer more advice for parents of older children in the future.

The videos available from the Information Service for Parents demonstrate practical advice for parents and parents-to-be, including:

• how much weight should I put on during pregnancy?
• what’s involved in a caesarean section?
• how do I know if I have postnatal depression? 
• how can I get my baby to sleep?

There are already around 670,000 visits per month to the pregnancy and baby webpages on NHS Choices.

How can I sign up to this service?

Visit www.nhs.uk/parents to sign up to the service or find out more information. Alternatively, you can sign up at a midwife appointment or at pregnancy, child or parenting support organisations such as NCT, as well as a host of websites.

What else has been announced for parents today?

The NHS Information Service for Parents was announced alongside a trial of free parenting classes for all parents of children aged five years and under in:

• Middlesbrough
• High Peak (Derbyshire)
• Camden (London)

Mums and dads will be able to use vouchers to pay for the parenting classes, which are being offered by a large group of children’s and parenting charities. These parenting class vouchers are available from Boots stores, children’s centres and health visitors.

The government has also launched a trial of subsidised relationship support sessions to help expectant mothers and fathers, and those with children up to the age of two. These sessions are being offered in York, Leeds, North Essex, Hackney and City of London, by Relate, The Tavistock Centre for Couple Relationships and the Fatherhood Institute. The sessions are set to include help with:

• managing new roles and responsibilities in your relationship
• dealing with the emotional impact of having a child
• learning negotiating and compromising skills
• balancing your role as a parent and as a partner
• coping with issues such as lack of sleep and mess

Links To The Headlines

No 10 guide to changing nappies and baby talk. The Daily Telegraph, May 18 2012

No 10 scheme will text and email parents with child-rearing tips from choosing baby names to changing nappies. Daily Mail, May 18 2012

Marriage counselling for tired new parents. The Independent, May 18 2012

“Dieting in pregnancy is good for you,” according to The Independent, while the Daily Mail has warned pregnant women not to eat for two since “piling on the pounds during pregnancy” increases the risk of complications.

Both these news stories are based on a study that compared ways to manage weight during pregnancy, but did not tell women to diet or look at the effects of overeating, as the headlines implied. Instead, the research reviewed previous studies to look at how diet, exercise or a combination of the two affected maternal weight gain and the risk of health problems for babies. In particular, it found that compared to other interventions such as exercise, following a diet plan (not a weight-loss diet) during pregnancy was more effective at reducing the amount of weight mothers gained. This had no adverse effect on the baby and reduced the risk of pre-eclampsia, diabetes, high blood pressure and premature birth.

This large study comes in the wake of concerns about the growing problem of obesity in pregnancy, which can cause serious problems for the mother and is a risk factor for later obesity in the child. It has found that dieting during pregnancy to maintain a healthy weight is safe, effective and has no effect on the baby’s birth weight, a factor which many woman worry about.

Currently, pregnant women are advised not to “eat for two” or reduce their calories, but to follow a healthy, varied diet with plenty of fruit and vegetables and a minimal intake of foods that are high in fat and sugar. Women who suspect they are overweight or obese are advised to talk to a dietitian, who will help them with a weight management programme.

Where did the story come from?

The study was carried out by researchers from several institutions in Europe, including Queen Mary University of London and the University of Birmingham. It was funded by the National Institute for Health Research’s Health Technology Assessment Programme.

Predictably, many newspapers made a meal of reporting this research, warning women not to “eat for two” even though women have been advised against doing this for several years now. The Metro’s headline that expectant mothers were being “urged to go on a diet” was also misleading. The study did not advise all women to follow a calorie-controlled diet but instead suggested that dietary interventions should be targeted at women who are obese or overweight. The paper’s photo of a pregnant woman holding weights was also misleading, since the study found diet to be more effective than exercise at reducing weight in pregnancy.

What kind of research was this?

This meta-analysis combined the results of randomised controlled trials which had looked at the effects of diet, exercise or a combination of the two on weight gain in pregnancy. Researchers also explored whether such interventions had any other effects during pregnancy and birth, and whether they affected the weight of the baby.

The researchers point out that obesity is a “growing threat” to women of childbearing age, with half the population being either overweight or obese. In Europe and the US, 20–40% of women gain more than the recommended weight during pregnancy. The researchers say that excessive weight gain during pregnancy is associated with adverse pregnancy outcomes, while for the children maternal obesity is a risk factor for obesity during childhood, which can persist into adulthood.

The authors argue that there is a need to identify safe and effective ways to help women manage their weight during pregnancy.

What did the research involve?

The authors analysed the results of 44 randomised controlled trials involving over 7,000 women.

They conducted searches of several electronic databases to find trials on the subject of pregnancy and weight. They also searched for relevant unpublished studies in sources of information such as conference databases. From these, they selected randomised controlled trials that tested the effects of dietary or lifestyle interventions on maternal and baby weight, as well as maternal and foetal outcomes.

The interventions in the trials were classified into three groups: mainly diet-based, physical activity-based, or based on both diet and physical activity. Studies were assessed for the quality of their design and methods to minimise the risk of bias.

The main outcome assessed was weight-related changes in the mother and baby, but researchers also looked at whether diet or exercise were associated with the risk of other critical pregnancy outcomes, including gestational diabetes, pre-eclampsia (a dangerous complication of pregnancy), premature delivery, stillbirth and shoulder dystocia (an emergency during childbirth where one of the baby’s shoulders becomes stuck behind the mother’s pubic bone). They summarised the strength of the evidence for these outcomes using an established system for grading evidence.

To explore possible further adverse effects, they undertook a separate search and review of the safety of diet and exercise in pregnancy, based on established methods. They analysed the data from the selected trials using standard statistical methods.

What were the basic results?

The researchers’ analysis included 44 randomised controlled trials involving 7,278 women, looking at the effects of diet, exercise or a combination of the two.

The researchers compared the outomes seen in women who were assigned interventions and women in control groups (who were not offered any interventions). They found that:

• Women who dieted, exercised or did both gained on average 1.42kg less than women in the control groups (95% confidence interval [CI] 0.95 to 1.89kg).
• Dieting, exercising, or doing both had no significant effect on the baby’s birth weight (mean difference -50g, 95% CI -100 to 0g), or whether babies were large or small for gestation age (the amount of time they had spent in the womb).
• On its own, physical activity was associated with a reduced birth weight of 60g on average (95% CI -120 to -10g).
• Diet, exercise, or both reduced the risk of pre-eclampsia (relative risk [RR] 0.74, 95% CI 0.60 to 0.92) and shoulder dystocia (RR 0.39, 95% CI 0.22 to 0.70), with no significant effect on other critically important outcomes.
• Dietary intervention resulted in the largest reduction in mothers’ weight gain during pregnancy. Compared with controls, women following dietary interventions were 3.84kg lighter and had better pregnancy outcomes than with other interventions (95% CI 2.45 to 5.22kg).

The overall evidence rating for the underlying studies was reported as low to very low for important outcomes such as pre-eclampsia, gestational diabetes, gestational hypertension and preterm delivery.

How did the researchers interpret the results?

The researchers concluded that diet and exercise can reduce maternal weight gain and improve outcomes for both mother and baby, with dietary intervention being the most effective. The diets in the trials included:

• a conventional balanced diet (based on an energy intake of 18–24kJ per kg of body weight)
• a low-glycaemic diet with unprocessed whole grains, fruits, beans and vegetables
• a diet with a maximum of 30% fat, 15–20% protein and 50–55% carbohydrate

Based on their findings, the researchers suggest that regular advice on planned nutritional intake should be provided to woman from early pregnancy onwards, targeting overweight and obese women who they say would benefit most.

Conclusion

This study has found that dieting during pregnancy to maintain a healthy weight is safe, effective and has no consequential effect on the baby’s birth weight, a factor which many women worry about.

It’s important to correct some of the inaccurate news coverage of this research. The research highlights the importance of eating healthily during pregnancy, but does not mean that all pregnant women should be put on diets. Nor does it recommend a reversal of the current advice that women should not eat for two, which has long been discouraged.

While putting on too much weight can affect a woman’s health and increase the risk of complications, gaining too little weight can also cause problems and mean the body is not storing enough fat. The current advice is not to go on a weight-loss or calorie-restricted diet during pregnancy, although a woman’s midwife or GP may have special advice if she weighs more than 100kg. Instead, current advice is based on eating a balanced diet and managing weight at an appropriate level. While it’s unlikely to make juicy headlines, the simple fact is that women should eat a normal amount and a balanced range of nutrients.

Weight gain in pregnancy varies greatly, although most pregnant women can expect to gain 8–14kg, most of it after week 20, as the baby grows and the body lays down enough fat to make breast milk after the baby is born. The medical team supporting a woman during pregnancy will monitor her changes in weight and diet, and will make appropriate suggestions to help her and her baby be as healthy as possible.

Links To The Headlines

Pregnant women should not 'eat for two'. The Daily Telegraph, May 18 2012

Mums-to-be urged to go on a diet rather than 'eat for two'. Metro, May 18 2012

Now dieting in pregnancy is good for you. The Independent, May 18 2012

DON'T eat for two: Piling on the pounds during pregnancy increases risk of diabetes and high blood pressure. Daily Mail, May 18 2012

Links To Science

Thangaratinam S, Rogozińska E, Jolly K et al. Effects of interventions in pregnancy on maternal weight and obstetric outcomes: meta-analysis of randomised evidence. BMJ 2012; 344

“Good cholesterol” doesn’t lower heart attack risk, the Daily Mail has reported.

A great deal of research has previously suggested that higher levels of “good” HDL cholesterol reduce your risk coronary heart disease, while higher levels of “bad” LDL cholesterol increase your risk of a heart attack. However, it has been hard to tell whether HDL cholesterol directly reduces coronary heart disease risk as other medical, biological or lifestyle factors could be involved. To get round this, researchers have conducted a complex study identifying genes that raise levels HDL cholesterol, and then in turn looking at whether carrying these genes influences heart disease risk.

Researchers first identified genetic variants associated with high HDL levels and tested for them in several thousand people, including some who had had a heart attack. They found that carrying these ‘HDL cholesterol genes’ had no effect on the risk of a heart attack. From this, the researchers concluded that there is no direct relationship between HDL cholesterol and coronary heart disease, and therefore that other factors must be involved.

This is a complex study that challenges the commonly held belief that having higher HDL cholesterol will reduce heart attack risk. However, as it only looked at a particular set of genetic variations, it cannot provide the whole answer and tell us whether HDL cholesterol does or does not affect coronary heart disease, and how this effect might come about. An important question is whether things that increase HDL cholesterol levels during our lifetime (i.e. after our genetics are determined), such as exercise and certain medications, can then improve our heart disease risk.

Where did the story come from?

The study was carried out by researchers from Harvard Medical School and was funded by the US National Institutes of Health, Wellcome Trust, European Union, British Heart Foundation and German Federal Ministry of Education and Research. The study was published in the peer-reviewed medical journal The Lancet.

The media generally oversimplified what is a complex analysis. Also, captions referring to cholesterol intake through diet have no direct relevance to this research, which examined the genetic factors that determine HDL cholesterol levels and not the influence of dietary sources.

What kind of research was this?

There are two broad types of cholesterol in the body that are each associated with altered risk of cardiovascular problems: high-density lipoprotein (HDL) and low-density lipoprotein (LDL). LDL cholesterol is often referred to as “bad” cholesterol, as research has found that raised levels of LDL are associated with an increased risk of heart attacks. Conversely, previous observational studies have tended to show that people with higher levels of HDL (“good”) cholesterol have a lower risk of coronary heart disease (CHD).

However, it is difficult to prove that HDL cholesterol directly lowers people’s risk of CHD. For example, other factors in a person’s health and lifestyle might influence both HDL levels and CHD risk, so could be responsible for the apparent relationship between the two.

This study used a complex genetic analysis concept, called “mendelian randomisation analysis”, to investigate the relationship between genes, HDL cholesterol and CHD. Broadly speaking, Mendelian randomisation analysis looks at whether genetics that determine one factor (such as HDL cholesterol levels) are directly associated with the risk of an outcome (such as heart disease).

In this case, the researchers considered the theory that if increased HDL directly reduces CHD risk, then carriers of genetic variants that confer a high concentration of HDL cholesterol should have a reduced risk of CHD. If genetic determinants of HDL cholesterol had no relationship to CHD risk, then there isn’t a causal relationship between the two and other factors are likely to be involved.

This mendelian analysis has the important limitation that in looking at purely genetic factors, it does not look at how environmental, health and lifestyle factors then influence both HDL levels and CHD risk - basically, all the other things in our lifetime that occur after our genetics are determined at conception.

What did the research involve?

The researchers first identified a certain rare form of a gene called the endothelial lipase gene (LIPG Asn396Ser). This particular form of the gene, carried by about 2.6% of the population, was associated with levels of HDL cholesterol. Carriers of this gene variant had consistently higher levels of HDL (good) cholesterol compared to non-carriers, but no difference in their levels of LDL (bad) cholesterol or other blood fat levels. Based on the influence that carrying this LIPG variant had on HDL cholesterol levels, the researchers calculated that if the relationship between HDL cholesterol and CHD was causal, then they would expect carriers of this variant to have a 13% reduced risk of CHD.

To test whether carrying the gene variant had this great an effect, they used a case-control study that included 20,913 people who had had a heart attack (the cases) and 95,407 control participants. They examined whether, as they expected, carriers of the variant had around a 13% reduced risk of being among the cases and to have had a heart attack.

In another part of the study, they examined further gene variants in what they called a “genetic score”. They identified the 14 gene variants that were most commonly associated with HDL cholesterol levels, and the 13 gene variants that were most commonly associated with LDL cholesterol. They tested these variants in a further 12,482 cases who had had a heart attack and 41,331 controls.

What were the basic results?

Carriers of the LIPG genetic variant (Asn396Ser) had HDL cholesterol levels that were slightly higher than people who did not carry this gene (about 0.14mmol/L higher). However, while this led researchers to  expect that people carrying this variant would have around a 13% reduced odds of having had a heart attack, they found that carrying this variant had no significant effect on risk of a heart attack (odds ratio [OR] for heart attack 0.99, 95% confidence interval [CI] 0.88 to 1.11).

Following this phase, the researchers looked at a person’s carriage of up to 14 variants that were associated with higher HDL cholesterol levels. They once again found that an increased ‘HDL genetic score’ was not significantly associated with odds of having a heart attack. However, when they examined the LDL genetic score (based on a person’s carriage of up to 13 variants associated with higher LDL cholesterol levels), they found that this was associated with increased odds of having a heart attack (OR 2.13, 95% CI 1.69 to 2.69). In short, genetic variants that increased a person’s LDL cholesterol level were associated with higher CHD risk, as expected.

How did the researchers interpret the results?

The researchers concluded that certain genetic variants that raise blood HDL cholesterol do not seem to be related to the risk of heart attacks. They said that this data “challenges the concept” that raising HDL cholesterol levels will directly translate into reduced risk of a heart attack.

Conclusion

Previous research has tended to show that HDL cholesterol is “good” for you and higher levels reduce your risk coronary heart disease, while LDL cholesterol is “bad” for you and higher levels increase your risk of a heart attack. This complex research aimed to avoid the problem of the influence of other medical, biological or lifestyle influences by concentrating on genetics linked to HDL cholesterol and how closely they related to the risk of heart disease. If HDL cholesterol is directly related to CHD risk, then genes associated with high HDL levels should be directly associated with lower heart attack risk. Researchers carried out their study based on the theory that because our genetics are randomly assigned, participants can be considered to be randomly allocated to their circumstances and, therefore, equal.

However, the research did not find that HDL genetics determines the risk of heart disease. Instead, the gene variants that were associated with higher HDL cholesterol levels had no association with heart attack risk. This suggests that there may be no direct relationship between HDL cholesterol and coronary heart disease and, therefore, that other factors must be involved.

When the researchers examined gene variants that caused a person to have higher LDL (“bad”) cholesterol levels, they found that carriers of these variants were more likely to have had a heart attack than people without the variants. This would suggest that there is a direct causal relationship between LDL cholesterol and coronary heart disease, but not HDL cholesterol.

This is a complex study that challenges the commonly held belief that having higher HDL cholesterol will reduce heart attack risk. However, this study alone cannot provide the whole answer and tell us whether HDL cholesterol has any effect at all on coronary heart disease, and how this effect might be medicated. Also, only a few gene variants were examined and there may be many other genetic influences on HDL cholesterol and other blood fats.

Importantly, while our genetics are determined at conception, the environment that we live in for the remainder of our lives is likely to have an influence. Therefore, it is not possible to say how much our genetics influence our cholesterol compared with the many other risk factors for heart disease (such as diabetes and lifestyle factors including smoking, alcohol and exercise). Exercise in particular is thought to raise HDL levels during our lifetime, regardless of our genetic assignment at conception. This study cannot tell us how raising HDL cholesterol levels in adult life could influence coronary heart disease risk.

Analysis by Bazian

Links To The Headlines

'Good' cholesterol is not so great for you as study finds it doesn't lower heart attack risk. Daily Mail, May 18 2012

Eating 'good cholesterol' could be a waste of time. Metro, May 18 2012

Links To Science

Voight BF, Peloso GM, Orho-Melander M, et al. Plasma HDL cholesterol and risk of myocardial infarction: a mendelian randomisation study. Lancet. Published online May 17 2012