Modelling the relationship between obesity and mental health in children and adolescents: findings from the Health Survey for England 2007

A number of studies have reported significant associations between obesity and poor psychological wellbeing in children but findings have been inconsistent.

METHODS

This study utilised data from 3,898 children aged 5-16 years obtained from the Health Survey for England 2007. Information was available on Body Mass Index (BMI), parental ratings of child emotional and behavioural health (Strengths and Difficulties Questionnaire), self-reported physical activity levels and sociodemographic variables. A multilevel modelling approach was used to allow for the clustering of children within households.

RESULTS

Curvilinear relationships between both internalising (emotional) and externalising (behavioural) symptoms and adjusted BMI were observed. After adjusting for potential confounders the relationships between obesity and psychological adjustment (reported externalising and internalising symptoms) remained statistically significant. Being overweight, rather than obese, had no impact on overall reported mental health. 17% of children with obesity were above the suggested screening threshold for emotional problems, compared to 9% of non-obese children. Allowing for clustering and potential confounding variables children classified as obese had an odds ratio (OR) of 2.13 (95% CI 1.39 to 3.26) for being above the screening threshold for an emotional disorder compared to non-obese young people. No cross-level interactions between household income and the relationships between obesity and internalising or externalising symptoms were observed.

CONCLUSIONS

In this large, representative, UK-based community sample a curvilinear association with emotional wellbeing was observed for adjusted BMI suggesting the possibility of a threshold effect. Further research could focus on exploring causal relationships and developing targeted interventions.

Reduced or modified dietary fat for preventing cardiovascular disease

BACKGROUND

Reduction and modification of dietary fats have differing effects on cardiovascular risk factors (such as serum cholesterol), but their effects on important health outcomes are less clear.

OBJECTIVES

To assess the effect of reduction and/or modification of dietary fats on mortality, cardiovascular mortality, cardiovascular morbidity and individual outcomes including myocardial infarction, stroke and cancer diagnoses in randomised clinical trials of at least 6 months duration.

SEARCH STRATEGY

For this review update, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE, were searched through to June 2010. References of Included studies and reviews were also checked.

SELECTION CRITERIA

Trials fulfilled the following criteria: 1) randomised with appropriate control group, 2) intention to reduce or modify fat or cholesterol intake (excluding exclusively omega-3 fat interventions), 3) not multi factorial, 4) adult humans with or without cardiovascular disease, 5) intervention at least six months, 6) mortality or cardiovascular morbidity data available.

DATA COLLECTION AND ANALYSIS

Participant numbers experiencing health outcomes in each arm were extracted independently in duplicate and random effects meta-analyses, meta-regression, sub-grouping, sensitivity analyses and funnel plots were performed.

MAIN RESULTS

This updated review suggested that reducing saturated fat by reducing and/or modifying dietary fat reduced the risk of cardiovascular events by 14% (RR 0.86, 95% CI 0.77 to 0.96, 24 comparisons, 65,508 participants of whom 7% had a cardiovascular event, I(2) 50%). Subgrouping suggested that this reduction in cardiovascular events was seen in studies of fat modification (not reduction - which related directly to the degree of effect on serum total and LDL cholesterol and triglycerides), of at least two years duration and in studies of men (not of women). There were no clear effects of dietary fat changes on total mortality (RR 0.98, 95% CI 0.93 to 1.04, 71,790 participants) or cardiovascular mortality (RR 0.94, 95% CI 0.85 to 1.04, 65,978 participants). This did not alter with sub-grouping or sensitivity analysis.Few studies compared reduced with modified fat diets, so direct comparison was not possible.

AUTHORS' CONCLUSIONS

The findings are suggestive of a small but potentially important reduction in cardiovascular risk on modification of dietary fat, but not reduction of total fat, in longer trials. Lifestyle advice to all those at risk of cardiovascular disease and to lower risk population groups, should continue to include permanent reduction of dietary saturated fat and partial replacement by unsaturates. The ideal type of unsaturated fat is unclear.

Interventions to change the behaviour of health professionals and the organisation of care to promote weight reduction in overweight and obese people

BACKGROUND

The prevalence of obesity is increasing globally and will, if left unchecked, have major implications for both population health and costs to health services.

OBJECTIVES

To assess the effectiveness of strategies to change the behaviour of health professionals and the organisation of care to promote weight reduction in overweight and obese people.

SEARCH STRATEGY

We updated the search for primary studies in the following databases, which were all interrogated from the previous (version 2) search date to May 2009: The Cochrane Central Register of Controlled Trials (which at this time incorporated all EPOC Specialised Register material) (The Cochrane Library 2009, Issue 1), MEDLINE (Ovid), EMBASE (Ovid), CINAHL (EBSCO), and PsycINFO (Ovid). We identified further potentially relevant studies from the reference lists of included studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) that compared routine provision of care with interventions aimed either at changing the behaviour of healthcare professionals or the organisation of care to promote weight reduction in overweight or obese adults.

DATA COLLECTION AND ANALYSIS

Two reviewers independently extracted data and assessed study quality.

MAIN RESULTS

We included six RCTs, involving more than 246 health professionals and 1324 overweight or obese patients. Four of the trials targeted professionals and two targeted the organisation of care. Most of the studies had methodological or reporting weaknesses indicating a risk of bias.Meta-analysis of three trials that evaluated educational interventions aimed at GPs suggested that, compared to standard care, such interventions could reduce the average weight of patients after a year (by 1.2 kg, 95% CI -0.4 to 2.8 kg); however, there was moderate unexplained heterogeneity between their results (I(2) = 41%). One trial found that reminders could change doctors' practice, resulting in a significant reduction in weight among men (by 11.2 kg, 95% CI 1.7 to 20.7 kg) but not among women (who reduced weight by 1.3 kg, 95% CI -4.1 to 6.7 kg). One trial found that patients may lose more weight after a year if the care was provided by a dietitian (by 5.6 kg, 95% CI 4.8 to 6.4 kg) or by a doctor-dietitian team (by 6 kg, 95% CI 5 to 7 kg), as compared with standard care. One trial found no significant difference between standard care and either mail or phone interventions in reducing patients' weight.

AUTHORS' CONCLUSIONS

Most of the included trials had methodological or reporting weaknesses and were heterogeneous in terms of participants, interventions, outcomes, and settings, so we cannot draw any firm conclusions about the effectiveness of the interventions. All of the evaluated interventions would need further investigation before it was possible to recommend them as effective strategies.

Objectively measured habitual physical activity in a highly obesogenic environment

BACKGROUND

While the prevalence of overweight and obesity among children continues to grow nationally, prevalence in the North-East of England is among the highest in the UK. The objective of this study was to investigate the habitual physical activity levels in a particularly obesogenic environment in the North-East of England.

METHODS

Eight primary schools were selected using a stratified random sampling frame ranking average deprivation levels. Participating children (n = 246, mean age 10 years) wore an accelerometer (Actigraph, GT-256) over five consecutive days (weekend plus three weekdays). Total daily moderate-to-vigorous intensity physical activity was calculated using thresholds by Puyau and colleagues.

RESULTS

Only 7% (17/246) of children were sufficiently active. Boys were more physically active than girls (766 +/- 268 vs. 641 +/- 202 counts/min, 95% CI for the difference 63-186 cpm.). Total physical activity was not influenced significantly by deprivation levels or weight status, and there were no significant differences in physical activity between school or weekend days.

CONCLUSIONS

The North-East of England is a recognized 'hot spot' for paediatric obesity and the present study shows that low levels of habitual physical activity are typical. Choice of accelerometry threshold affects both the apparent amount of physical activity and the ability to detect groups with particularly low levels of physical activity.

Interventions for treating obesity in children

BACKGROUND

Child and adolescent obesity is increasingly prevalent, and can be associated with significant short- and long-term health consequences.

OBJECTIVES

To assess the efficacy of lifestyle, drug and surgical interventions for treating obesity in childhood.

SEARCH STRATEGY

We searched CENTRAL on The Cochrane Library Issue 2 2008, MEDLINE, EMBASE, CINAHL, PsycINFO, ISI Web of Science, DARE and NHS EED. Searches were undertaken from 1985 to May 2008. References were checked. No language restrictions were applied.

SELECTION CRITERIA

We selected randomised controlled trials (RCTs) of lifestyle (i.e. dietary, physical activity and/or behavioural therapy), drug and surgical interventions for treating obesity in children (mean age under 18 years) with or without the support of family members, with a minimum of six months follow up (three months for actual drug therapy). Interventions that specifically dealt with the treatment of eating disorders or type 2 diabetes, or included participants with a secondary or syndromic cause of obesity were excluded.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed trial quality and extracted data following the Cochrane Handbook. Where necessary authors were contacted for additional information.

MAIN RESULTS

We included 64 RCTs (5230 participants). Lifestyle interventions focused on physical activity and sedentary behaviour in 12 studies, diet in 6 studies, and 36 concentrated on behaviorally orientated treatment programs. Three types of drug interventions (metformin, orlistat and sibutramine) were found in 10 studies. No surgical intervention was eligible for inclusion. The studies included varied greatly in intervention design, outcome measurements and methodological quality.Meta-analyses indicated a reduction in overweight at 6 and 12 months follow up in: i) lifestyle interventions involving children; and ii) lifestyle interventions in adolescents with or without the addition of orlistat or sibutramine. A range of adverse effects was noted in drug RCTs.

AUTHORS' CONCLUSIONS

While there is limited quality data to recommend one treatment program to be favoured over another, this review shows that combined behavioural lifestyle interventions compared to standard care or self-help can produce a significant and clinically meaningful reduction in overweight in children and adolescents. In obese adolescents, consideration should be given to the use of either orlistat or sibutramine, as an adjunct to lifestyle interventions, although this approach needs to be carefully weighed up against the potential for adverse effects. Furthermore, high quality research that considers psychosocial determinants for behaviour change, strategies to improve clinician-family interaction, and cost-effective programs for primary and community care is required.

The impact of maternal BMI status on pregnancy outcomes with immediate short-term obstetric resource implications: a meta-analysis

Obesity is rising in the obstetric population, yet there is an absence of services and guidance for the management of maternal obesity. This systematic review aimed to investigate relationships between obesity and impact on obstetric care. Literature was systematically searched for cohort studies of pregnant women with anthropometric measurements recorded within 16-weeks gestation, followed up for the term of the pregnancy, with at least one obese and one comparison group. Two researchers independently data-extracted and quality-assessed each included study. Outcome measures were those that directly or indirectly impacted on maternity resources. Primary outcomes included instrumental delivery, caesarean delivery, duration of hospital stay, neonatal intensive care, neonatal trauma, haemorrhage, infection and 3rd/4th degree tears. Meta-analysis shows a significant relationship between obesity and increased odds of caesarean and instrumental deliveries, haemorrhage, infection, longer duration of hospital stay and increased neonatal intensive care requirement. Maternal obesity significantly contributes to a poorer prognosis for mother and baby during delivery and in the immediate post-partum period. National clinical guidelines for management of obese pregnant women, and public health interventions to help safeguard the health of mothers and their babies are urgently required.

WITHDRAWN: Dieting to reduce body weight for controlling hypertension in adults

BACKGROUND

As early as the 1920's, researchers noted a relationship between caloric restriction, weight loss and a decreased incidence of hypertension (Terry 1922, Preble 1923, Bauman 1928, Master 1929). In 1988 a meta-analysis of aggregate data from 12 prospective studies, including 5 randomized controlled trials (RCTs), found that on average each 1 kilogram decrease in body weight in obese hypertensive patients was associated with a 2.4 mm Hg systolic and 1.5 mm Hg diastolic decrease in blood pressure (Staessen 1988). Blood pressure reductions were not dependent upon degree of baseline obesity.This review aims to: 1) update the work of Staessen (Staessen 1988) looking specifically at randomized controlled trials, and 2) assess whether any of the trials assess effects of weight-reducing diets on clinical outcomes such as quality of life, morbidity or mortality.

OBJECTIVES

Evaluate whether weight-loss diets are more effective than regular diets or other antihypertensive therapies in controlling blood pressure and preventing morbidity and mortality in hypertensive adults.

SEARCH STRATEGY

MEDLINE and The Cochrane Library were searched through November 1997. Trials known to experts in the field were included through June 1998.

SELECTION CRITERIA

For inclusion in the review, trials were required to meet each of the following criteria: 1) randomized controlled trials with one group assigned to a weight-loss diet and the other group assigned to either normal diet or antihypertensive therapy; 2) ambulatory adults with a mean blood pressure of at least 140 mm Hg systolic and/or 90 mm Hg diastolic; 3) active intervention consisting of a calorie-restricted diet intended to produce weight loss (excluded studies simultaneously implementing multiple lifestyle interventions where the effects of weight loss could not be disaggregated); and 4) outcome measures included weight loss and blood pressure.

DATA COLLECTION AND ANALYSIS

Studies were dual abstracted by two independent reviewers using a standardized form designed specifically for this review. The primary mode of analysis was qualitative; graphs of effect sizes for individual studies were also used.

MAIN RESULTS

Eighteen trials were found. Only one small study of inadequate power reported morbidity and mortality outcomes. None addressed quality of life or general well being issues. In general, participants assigned to weight-reduction groups lost weight compared to control groups.Six trials involving 361 participants assessed a weight-reducing diet versus a normal diet. The data suggested weight loss in the range of 4% to 8% of body weight was associated with a decrease in blood pressure in the range of 3 mm Hg systolic and diastolic. Three trials involving 363 participants assessed a weight-reducing diet versus treatment with antihypertensive medications. These suggested that a stepped-care approach with antihypertensive medications produced greater decreases in blood pressure (in the range of 6/5 mm Hg systolic/diastolic) than did a weight-loss diet. Trials that allowed adjustment of participants' antihypertensive regimens suggested that patients required less intensive antihypertensive drug therapy if they followed a weight-reducing diet. Data was insufficient to determine the relative efficacy of weight-reduction versus changes in sodium or potassium intake or exercise.

AUTHORS' CONCLUSIONS

Weight-reducing diets in overweight hypertensive persons can affect modest weight loss in the range of 3-9% of body weight and are probably associated with modest blood pressure decreases of roughly 3 mm Hg systolic and diastolic. Weight-reducing diets may decrease dosage requirements of persons taking antihypertensive medications.

WITHDRAWN: Advice on low-fat diets for obesity

BACKGROUND

Overweight and obesity are global health problems contributing to an ever increasing noncommunicable disease burden. Calorie restriction can achieve short-term weight loss but the weight loss has not been shown to be sustainable in the long-term. An alternative approach to calorie restriction is to lower the fat content of the diet. However, the long-term effects of fat-restricted diets on weight loss have not been established.

OBJECTIVES

To assess the effects of advice on low-fat diets as a means of achieving sustained weight loss, using all available randomised clinical trials. This review focused primarily on participants who were overweight or clinically obese and were dieting for the purpose of weight reduction. Since we were particularly interested in the ability of participants to sustain weight loss over a longer period of time, we focused on studies of 'free living' men and women who were given dietary advice rather than provision of food or money to purchase food.

SEARCH STRATEGY

We searched the Cochrane Controlled Trials Register (Cochrane Library Issue 2, 2001), MEDLINE (up to February 2002), and EMBASE (up to February 2002). We also searched the Science Citation Index (up to January 2001) and bibliographies of studies identified. Date of latest search: February 2002.

SELECTION CRITERIA

Trials were included if they fulfilled the following criteria: 1) they were randomised controlled clinical trials of low-fat diets versus other weight-reducing diets, 2) the primary purpose of the study was weight loss, 3) participants were followed for at least six months, 4) the study participants were adults (18 years or older) who were overweight or obese (BMI >25 kg/m2) at baseline. Studies including pregnant women or patients with serious medical conditions were excluded. Two people independently applied the inclusion criteria to the studies identified. Disagreement was resolved by discussion or by intervention of a third party.

DATA COLLECTION AND ANALYSIS

Data were extracted by three independent reviewers and meta-analysis performed using a random effects model. Weighted mean differences of weight loss were calculated for treatment and control groups at 6, 12 and 18 months.

MAIN RESULTS

Four studies were included at the six month follow-up, five studies at the 12 month follow-up and three studies at the 18 month follow-up. There was no significant difference in weight loss between the two groups at six months (WMD 1.7 kg, 95% CI -1.4 to 4.8 kg). The weighted sum of weight loss in the low fat group was -5.08 kg (95% CI -5.9 to -4.3 kg) and in the control group was -6.5 kg, (95% CI -7.3 to -5.7 kg). There was no significant difference in weight loss between the two groups at 12 months (WMD 1.1 kg, 95% CI -1.6 to 3.8 kg). The weighted sum of weight loss in the low fat group was -2.3 kg (95% CI -3.2 to -1.4 kg) and in the control group was -3.4 kg (95% CI -4.2 to -2.6 kg). There was no significant difference in weight loss between the two groups at 18 months (WMD 3.7 kg, 95% CI - 1.8 to 9.2). The weighted sum of weight loss in the control group was -2.3 kg (95% CI -3.5 to -1.2 kg) and in the low fat group there was a weight gain of 0.1 kg (95% CI -0.8 to 1 kg). There was significant heterogeneity in the results for weight loss at six months and 12 months. Apart from one study which showed a slight but statistically significant difference in total cholesterol in the low fat group at one year follow-up, there were no significant differences between the dietary groups for other outcome measures such as serum lipids, blood pressure and fasting plasma glucose. Studies measuring other factors such as perceived wellness and quality of life reported conflicting results.

AUTHORS' CONCLUSIONS

The review suggests that fat-restricted diets are no better than calorie restricted diets in achieving long term weight loss in overweight or obese people. Overall, participants lost slightly more weight on the control diets but this was not significantly different from the weight loss achieved through dietary fat restriction and was so small as to be clinically insignificant.

Dietary advice for the prevention of type 2 diabetes mellitus in adults

BACKGROUND

Prevention of type 2 diabetes in adults is a far better option than treatment, to alleviate pressure on health care providers and resources. However, there is no current review of the evidence regarding the efficacy of a diet-only intervention for prevention.

OBJECTIVES

To assess the effects of type and frequency of dietary advice for the prevention of type 2 diabetes mellitus.

SEARCH STRATEGY

We carried out a comprehensive search of The Cochrane Library, MEDLINE, EMBASE, CINAHL, AMED, bibliographies and contacted relevant experts.

SELECTION CRITERIA

All randomised controlled trials, of twelve months or longer, in which dietary advice for the prevention of type 2 diabetes was the only intervention in adults.

DATA COLLECTION AND ANALYSIS

The lead investigator performed all data extraction and quality scoring with duplication being carried out by one of the other four investigators independently with discrepancies resolved by discussion and consensus. Authors were contacted for missing data. Change data are presented.

MAIN RESULTS

Two trials which randomised 358 people to dietary treatment and control groups were identified. Longest duration of follow-up was six years. In the 6-year Da Qing IGT & Diabetes study, the incidence of type 2 diabetes in the control group was 67.7% (95% confidence interval (CI) 59.8% to 75.2%) which was reduced to 43.8% (95% CI 35.5% to 54.7%) in the diet group. Overall, the dietary intervention group had a 33% reduction in the incidence of diabetes after six years (P < 0.03). The Oslo Diet & Exercise Study (ODES) found significant (P<0.05) reductions in insulin resistance, fasting insulin (pmol/L), fasting C-peptide (pmol/L), fasting proinsulin (pmol/L), fasting blood glucose (mmol/L), BMI (kg/m(2)), mBP (mmHg) and fasting triglycerides (mmol/L), and a significant increase in fasting HDL cholesterol (mmol/L) and PAI-1 (U/ml) after 12 months of dietary intervention. Data on mortality, morbidity, health-related quality of life, adverse effects, costs were not reported in either study.

AUTHORS' CONCLUSIONS

There are no high quality data on the efficacy of dietary intervention for the prevention of type 2 diabetes. More well-designed, long-term studies, providing well-reported, high-quality data are required before proper conclusions can be made into the best dietary advice for the prevention of diabetes mellitus in adults.

Dietary advice for treatment of type 2 diabetes mellitus in adults

BACKGROUND

While initial dietary management immediately after formal diagnosis is an 'accepted' cornerstone of treatment of type 2 diabetes mellitus, a formal and systematic overview of its efficacy and method of delivery is not currently available.

OBJECTIVES

To assess the effects of type and frequency of different types of dietary advice for adults with type 2 diabetes.

SEARCH STRATEGY

We carried out a comprehensive search of The Cochrane Library, MEDLINE, EMBASE, CINAHL, AMED, bibliographies and contacted relevant experts.

SELECTION CRITERIA

All randomised controlled trials, of six months or longer, in which dietary advice was the main intervention.

DATA COLLECTION AND ANALYSIS

The lead investigator performed all data extraction and quality scoring with duplication being carried out by one of the other six investigators independently with discrepancies resolved by discussion and consensus. Authors were contacted for missing data.

MAIN RESULTS

Thirty-six articles reporting a total of eighteen trials following 1467 participants were included. Dietary approaches assessed in this review were low-fat/high-carbohydrate diets, high-fat/low-carbohydrate diets, low-calorie (1000 kcal per day) and very-low-calorie (500 kcal per day) diets and modified fat diets. Two trials compared the American Diabetes Association exchange diet with a standard reduced fat diet and five studies assessed low-fat diets versus moderate fat or low-carbohydrate diets. Two studies assessed the effect of a very-low-calorie diet versus a low-calorie diet. Six studies compared dietary advice with dietary advice plus exercise and three other studies assessed dietary advice versus dietary advice plus behavioural approaches. The studies all measured weight and measures of glycaemic control although not all studies reported these in the articles published. Other outcomes which were measured in these studies included mortality, blood pressure, serum cholesterol (including LDL and HDL cholesterol), serum triglycerides, maximal exercise capacity and compliance. The results suggest that adoption of regular exercise is a good way to promote better glycaemic control in type 2 diabetic patients, however all of these studies were at high risk of bias.

AUTHORS' CONCLUSIONS

There are no high quality data on the efficacy of the dietary treatment of type 2 diabetes, however the data available indicate that the adoption of exercise appears to improve glycated haemoglobin at six and twelve months in people with type 2 diabetes. There is an urgent need for well-designed studies which examine a range of interventions, at various points during follow-up, although there is a promising study currently underway.

Wholegrain cereals for coronary heart disease

BACKGROUND

There is increasing evidence from observational studies that wholegrains can have a beneficial effect on risk factors for coronary heart disease (CHD).

OBJECTIVES

The primary objective is to review the current evidence from randomised controlled trials (RCTs) that assess the relationship between the consumption of wholegrain foods and the effects on CHD mortality, morbidity and on risk factors for CHD, in participants previously diagnosed with CHD or with existing risk factors for CHD.

SEARCH STRATEGY

We searched CENTRAL (Issue 4, 2005), MEDLINE (1966 to 2005), EMBASE (1980 to 2005), CINAHL (1982 to 2005), ProQuest Digital Dissertations (2004 to 2005). No language restrictions were applied.

SELECTION CRITERIA

We selected randomised controlled trials that assessed the effects of wholegrain foods or diets containing wholegrains, over a minimum of 4 weeks, on CHD and risk factors. Participants included were adults with existing CHD or who had at least one risk factor for CHD, such as abnormal lipids, raised blood pressure or being overweight.

DATA COLLECTION AND ANALYSIS

Two of our research team independently assessed trial quality and extracted data. Authors of the included studies were contacted for additional information where this was appropriate.

MAIN RESULTS

Ten trials met the inclusion criteria. None of the studies found reported the effect of wholegrain diets on CHD mortality or CHD events or morbidity. All 10 included studies reported the effect of wholegrain foods or diets on risk factors for CHD. Studies ranged in duration from 4 to 8 weeks. In eight of the included studies, the wholegrain component was oats. Seven of the eight studies reported lower total and low density lipoproteins (LDL) cholesterol with oatmeal foods than control foods. When the studies were combined in a meta-analysis lower total cholesterol (-0.20 mmol/L, 95% confidence interval (CI) -0.31 to -0.10, P = 0.0001 ) and LDL cholesterol (0.18 mmol/L, 95% CI -0.28 to -0.09, P < 0.0001) were found with oatmeal foods. However, there is a lack of studies on other wholegrains or wholegrain diets.

AUTHORS' CONCLUSIONS

Despite the consistency of effects seen in trials of wholegrain oats, the positive findings should be interpreted cautiously. Many of the trials identified were short term, of poor quality and had insufficient power. Most of the trials were funded by companies with commercial interests in wholegrains. There is a need for well-designed, adequately powered, longer term randomised controlled studies in this area. In particular there is a need for randomised controlled trials on wholegrain foods and diets other than oats.

Trends in maternal obesity incidence rates, demographic predictors, and health inequalities in 36,821 women over a 15-year period

OBJECTIVE

The aim of this study was to identify trends in maternal obesity incidence over time and to identify those women most at risk and potential-associated health inequalities.

DESIGN

Longitudinal database study.

SETTING

James Cook University Hospital maternity unit, Middlesbrough, UK.

SAMPLE

A total of 36 821 women from 1 January 1990 to 31 December 2004.

METHODS

Trends in maternal obesity incidence over time were analysed using chi-square test for trend. Demographic predictor variables were analysed using multivariate logistic regression, adjusting for confounding factors after testing for multicollinearity. National census data were used to place the regional data into the context of the general population.

MAIN OUTCOME MEASURE

Trends in maternal obesity incidence. Demographic predictor variables included ethnic group, age, parity, marital status, employment and socio-economic disadvantage.

RESULTS

The proportion of obese women at the start of pregnancy has increased significantly over time from 9.9 to 16.0% (P<0.01). This is best described by a quadratic model (P<0.01) showing that the rate is accelerating; by 2010, the rate will have increased to 22% of this population if the trend continues. There is also a significant relationship with maternal obesity and mothers' residing in areas of most deprivation (odds ratio [OR]=2.44, 95% CI=1.98, 3.02, P<0.01), with increasing age (OR=1.04, 95% CI=1.04, 1.05, P<0.01), and parity (OR=1.17, 95% CI=1.12, 1.21, P<0.01).

CONCLUSIONS

The incidence of maternal obesity at the start of pregnancy is increasing and accelerating. Predictors of maternal obesity are associated with health inequalities, particularly socio-economic disadvantage.

Obesity in pregnancy: a study of the impact of maternal obesity on NHS maternity services

OBJECTIVE

To gain a detailed understanding of healthcare professionals' perceptions of the impact that caring for obese pregnant women has on maternity services.

DESIGN

Qualitative interview study using purposeful sampling and face-to-face interviews.

SETTING

Sixteen maternity units in NHS Trusts in the North East Government Office Region of England, UK.

SAMPLE

Thirty-three maternity and obstetric healthcare professionals with personal experience of managing the care of obese pregnant women.

METHODS

Semi-structured interviews with healthcare professionals representing each maternity unit in the region. Transcripts were analysed using systematic content analysis.

MAIN OUTCOME MEASURES

Views on the impact maternal obesity has on maternity services, the facilities required to care for obese mothers in pregnancy, and existing services directed towards maternal obesity.

RESULTS

Five dominant themes relating to service delivery emerged; booking appointments, equipment, care requirements, complications and restrictions, and current and future management of care. Many of the issues identified were associated with managing the care of obese women in pregnancy safely, resources and cost issues to be able to do this, multidisciplinary care requirements because of coexisting morbidities when the mother is obese, and restricted care options and patient choice.

CONCLUSIONS

Healthcare professionals in the North East of England feel that maternal obesity has a major impact on services and resource, on the health of both the mother and child, and on the psychological wellbeing of the mother.

Obesity and disability - a short review

The prevalence of both obesity and disability is increasing globally and there is now growing evidence to suggest that these two health priorities may be linked. This paper explores the evidence linking obesity to muscular-skeletal conditions, mental health disorders and learning disabilities in both adult and child populations. The impact of obesity on the four most prevalent disabling conditions in the UK (arthritis, mental health disorders, learning disabilities and back ailments) has been examined through novel data analysis of the 2001 Health Survey for England and UK Back Exercise And Manipulation trial data. Together these analyses strongly suggest that whether the cause or result of disability, obesity is undeniably implicated, thus presenting a serious public health priority. Future research efforts are required to strengthen the evidence base examining obesity in back disorders, mental health and learning disabilities, in order to improve current clinical management.

Independent associations between weight status and disability in adults: Results from the health survey for England

OBJECTIVES

While direct links between obesity and some illnesses are well-established, there is a relative paucity of research on associations between obesity and disabilities. The aim of this study was to test for significant associations between overweight and obesity and the presence of a wide range of disabling conditions in adults, controlling for sex, age, education, social class, income, cigarette smoking status and alcohol consumption.

STUDY DESIGN

Data were extracted from the Health Survey for England (2001); a cross-sectional survey of the community-dwelling population. In total, 8613 adult participants were included in the analysis.

METHODS

Multivariate logistic regression was employed to test whether the odds of having a range of disabling conditions are higher in the overweight and obese populations compared with those in the ideal weight range.

RESULTS

The risk of nearly all disabling conditions tested was elevated in the obese and morbidly obese groups. Of great importance for public health, the risks of musculoskeletal illness, arthritis and rheumatism, and personal care disability were significantly elevated, even in those in the overweight category (currently about half of the adult population living in the UK).

CONCLUSIONS

Obesity is independently associated with a range of disabling conditions in adults. The present study highlights the need for further research into the mechanisms by which these associations occur.

Risks and benefits of omega 3 fats for mortality, cardiovascular disease, and cancer: systematic review

OBJECTIVE

To review systematically the evidence for an effect of long chain and shorter chain omega 3 fatty acids on total mortality, cardiovascular events, and cancer.

DATA SOURCES

Electronic databases searched to February 2002; authors contacted and bibliographies of randomised controlled trials (RCTs) checked to locate studies.

REVIEW METHODS

Review of RCTs of omega 3 intake for (3) 6 months in adults (with or without risk factors for cardiovascular disease) with data on a relevant outcome. Cohort studies that estimated omega 3 intake and related this to clinical outcome during at least 6 months were also included. Application of inclusion criteria, data extraction, and quality assessments were performed independently in duplicate.

RESULTS

Of 15,159 titles and abstracts assessed, 48 RCTs (36,913 participants) and 41 cohort studies were analysed. The trial results were inconsistent. The pooled estimate showed no strong evidence of reduced risk of total mortality (relative risk 0.87, 95% confidence interval 0.73 to 1.03) or combined cardiovascular events (0.95, 0.82 to 1.12) in participants taking additional omega 3 fats. The few studies at low risk of bias were more consistent, but they showed no effect of omega 3 on total mortality (0.98, 0.70 to 1.36) or cardiovascular events (1.09, 0.87 to 1.37). When data from the subgroup of studies of long chain omega 3 fats were analysed separately, total mortality (0.86, 0.70 to 1.04; 138 events) and cardiovascular events (0.93, 0.79 to 1.11) were not clearly reduced. Neither RCTs nor cohort studies suggested increased risk of cancer with a higher intake of omega 3 (trials: 1.07, 0.88 to 1.30; cohort studies: 1.02, 0.87 to 1.19), but clinically important harm could not be excluded.

CONCLUSION

Long chain and shorter chain omega 3 fats do not have a clear effect on total mortality, combined cardiovascular events, or cancer.

The Cochrane Library: more systematic reviews on nutrition needed

The knowledge and relevance of nutrition as well as the demand for well-funded advices increase. The Cochrane Collaboration plays a leading role within the evidence-based medicine and practice. We advocate therefore more specialized nutritional interest within the Cochrane Collaboration. In case 'Nutrition' needs more attention within the Cochrane Library, one of the first priorities is deciding about whether to include non-randomized studies into the Specialized Register and generating lists of journals to handsearch for such a Specialized Register. Preparatory to these activities an inventory of Nutritional content within the Cochrane Library is needed. We estimate that reviews directly related to nutrition and those of borderline interest to nutrition represent less than 4% of all published reviews in The Cochrane Library.