Overweight children have poor bone strength relative to body weight, placing them at greater risk for forearm fractures

Introduction: Obesity is thought to be a protective factor for bones in adults but not in children based on the evidence of the greater incidence of forearm fractures in obese children. Our objective was to investigate the effect of adiposity on bone strength in relation to the mechanical challenge placed onto the forearm bones in case of a fall.

Methods: Cross sectional areas (CSA) were obtained at the mid- and distal radius by peripheral quantitative computed tomography in 486 children (241 boys), mean age 8.3 years (range 6.9–9.7), participating in the LOOK Project. The following parameters were measured: bone mass and bone CSA (both sites), and muscle and fat CSA (mid-forearm only). Bone strength indices combining bone size and total volumetric density were calculated at each site.

Results/Discussion: Overweight children (BMI > percentile equivalent to 25 kg/m² in adults) have higher bone parameters than normal-weight peers (Z-scores +0.6 to +0.9SD, p < 0.0001). These differences disappear after adjustment for muscle CSA. Adiposity (fat CSA/muscle CSA) was negatively correlated with bone mass, size and strength at the distal radius only (r = −0.1, p < 0.05). After adjustment for body weight (estimate of the load during a fall), the negative correlations were stronger and observed at both the mid- and distal radius (r = −0.37 to −0.55, p < 0.0001).

Conclusion. Overweight children have stronger bones due to greater muscle size. However, children with high fat mass relative to muscle mass (increased adiposity) have poorer bone strength, independent of weight, which may contribute to the increased risk of fracture in obese children.

Outcomes and costs of primary care surveillance and intervention for overweight or obese children : the LEAP 2 randomised controlled trial

Objective To determine whether ascertainment of childhood obesity by surveillance followed by structured secondary prevention in primary care improved outcomes in overweight or mildly obese children.

Design Randomised controlled trial nested within a baseline cross sectional survey of body mass index (BMI). Randomisation and outcomes measurement, but not participants, were blinded to group assignment.

Setting 45 family practices (66 general practitioners) in Melbourne, Australia.

Participants 3958 children visiting their general practitioner in May 2005-July 2006 were surveyed for BMI. Of these, 258 children aged 5 years 0 months up to their 10th birthday who were overweight or obese by International Obesity Taskforce criteria were randomised to intervention (n=139) or control (n=119) groups. Children who were very obese (UK BMI z score 3.0) were excluded.

Intervention Four standard consultations over 12 weeks targeting change in nutrition, physical activity, and sedentary behaviour, supported by purpose designed family materials.

Main outcomes measures Primary measure was BMI at 6 and 12 months after randomisation. Secondary measures were mean activity count/min by 7-day accelerometry, nutrition score from 4-day abbreviated food frequency diary, and child health related quality of life. Differences were adjusted for socioeconomic status, age, sex, and baseline BMI.

Results Of 781 eligible children, 258 (33%) entered the trial; attrition was 3.1% at 6 months and 6.2% at 12 months. Adjusted mean differences (intervention – control) at 6 and 12 months were, for BMI, –0.12 (95% CI –0.40 to 0.15, P=0.4) and –0.11 (–0.45 to 0.22, P=0.5); for physical activity in counts/min, 24 (–4 to 52, P=0.09) and 11 (–26 to 49, P=0.6); and, for nutrition score, 0.2 (–0.03 to 0.4, P=0.1) and 0.1 (–0.1 to 0.4, P=0.2). There was no evidence of harm to the child. Costs to the healthcare system were significantly higher in the intervention arm.

Conclusions Primary care screening followed by brief counselling did not improve BMI, physical activity, or nutrition in overweight or mildly obese 5-10 year olds, and it would be very costly if universally implemented. These findings are at odds with national policies in countries including the US, UK, and Australia.

A prospective study of overweight, physical activity and depressive symptoms in young women

This study examined the prospective associations of BMI, physical activity (PA), changes in BMI, and changes in PA, with depressive symptoms. Self-reported data on height, weight, PA, selected sociodemographic and health variables and depressive symptoms (CESD-10) were provided in 2000 and 2003 by 6,67 young adult women (22–27 years in 2000) participating in the Australian Longitudinal Study on Women's Health (ALSWH). Results of logistic regression analyses showed that the odds of developing depressive symptoms at follow-up (2003) were higher in women who were overweight or obese in 2000 than in healthy weight women, and lower in women who were active in 2000 than in sedentary women. Changes in BMI were significantly associated with increased odds of depressive symptoms at follow-up. Sedentary women who increased their activity had lower odds of depressive symptoms at follow-up than those who remained sedentary. Increases in activity among initially sedentary young women were protective against depressive symptoms even after adjusting for BMI changes. These findings indicate that overweight and obese young women are at risk of developing depressive symptoms. PA appears to be protective against the development of depressive symptoms, but does not attenuate the depressive symptoms associated with weight gain. However, among initially sedentary young women, even small increases in PA over time may reduce the odds of depressive symptoms, regardless of weight status.

Dose-response associations between screen time and overweight among youth

Objective. To examine dose-response associations between screen time and overweight, independent of physical activity and dietary intake.

Methods. Participants were 580 Dutch youth (13 years; 48% boys). Body mass index, waist circumference and skinfold thickness at four sites determined weight status. Questionnaires examined television viewing and computer use, participation in organized sport and high caloric snack and sugar-containing beverage consumption.

Results. There were no significant associations among boys. Compared with girls spending less than two hours/day in screen time, those who spent three to four hours/day were more likely to be classified as overweight by waist circumference (odds ratio [OR]=3.4; 95% confidence intervals [CI]=1.1-10.7; p=0.03), and this likelihood increased substantially among those spending more than four hours/day (OR=5.5; 95% CI=2.1-14.1; p≤0.0001).

Conclusions. Girls who spend three or more hours/day in screen time are at increased risk of being classified as overweight by waist circumference.

Comorbidites of overweight/obesity experienced in adolescence : longitudinal study

Objectives: Adolescent obesity is linked to measurable, asymptomatic metabolic and cardiovascular precursors, but its associations with adolescents’ experienced health and morbidity is less clear. The objective of this paper was to determine (1) Prevalence of comorbidities experienced by overweight/obese adolescents; (2) Associations between timing of overweight/obesity and morbidity.

Methods: Data were drawn from the three waves (1997, 2000, 2005) of the Health of Young Victorians Study (HOYVS), an Australian school-based longitudinal study. The main outcome measures were blood pressure; self- and parent-proxy reported health status (PedsQL, global health); self-reported mental health (SDQ), psychological distress (K-10), physical symptoms, sleep, asthma, and dieting; parent-reported health care needs (CSHCN screener) and visits. Regression methods, adjusted for sociodemographic factors, were used to assess associations with (1) Body mass index (BMI) status (non-overweight, overweight or obese) and (2) Timing of overweight/obesity ( never , childhood only , adolescence only , ‘persistent ).

Results: Of the 923 adolescents (20.2% overweight, 6.1% obese), 63.5% were categorised as ‘never’ overweight/obese, 8.5% as ‘childhood only’, 7.3% as ‘adolescence only’, and 20.8% as ‘persistent’. Current BMI status was strongly associated with poorer physical and global health, hypertension and dieting behaviours. Associations were weaker for emotional morbidity, and there was no clear evidence of association with any other variable. Other than dieting, adolescent morbidity was not associated with resolved childhood overweight/obesity.

Conclusions: Despite poorer overall health, overweight/obese adolescents were not more likely to report specific problems that might prompt health intervention. Morbidity was mainly associated with concurrent, rather than earlier, overweight/obesity.

The burden of overweight and obesity-related ill health in the UK

This paper reviews previous cost studies of overweight and obesity in the UK. It proposes a method for estimating the economic and health costs of overweight and obesity in the UK which could also be used in other countries. Costs of obesity studies were identified via a systematic search of electronic databases. Information from the WHO Burden of Disease Project was used to calculate the mortality and morbidity cost of overweight and obesity. Population attributable fractions for diseases attributable to overweight and obesity were applied to National Health Service (NHS) cost data to estimate direct financial costs. We estimate the direct cost of overweight and obesity to the NHS at £3.2 billion. Other estimates of the cost of obesity range between £480 million in 1998 and £1.1 billion in 2004 [Correction added after online publication 11 June 2007: 'of the cost of obesity' added after 'Other estimates']. There is wide variation in methods and estimates for the cost of overweight and obesity to the health systems of developed countries. The method presented here could be used to calculate the costs of overweight and obesity in other countries. Public health initiatives are required to address the increasing prevalence of overweight and obesity and reduce associated healthcare costs.

Assessing the burden of overweight and obesity : an example from the United Kingdom

Introduction: In this paper I review previous cost studies for overweight and obesity in the UK. I propose a method for estimating the economic and health costs of overweight and obesity in the UK which could also be used in other countries.

Methods: Costs of obesity studies were identified via a systematic search of electronic databases. Information from the WHO Burden of Disease Project was used to calculate the mortality and morbidity cost of overweight and obesity.
Population attributable fractions for diseases attributable
to overweight and obesity were applied to National Health Service (NHS) cost data to estimate direct financial costs.

Results: We estimate the direct cost of overweight and obesity to the NHS at £3.2 billion. Other estimates range between £480 million in 1998 and £1.1 billion in 2004. There is wide variation in methods and estimates for the cost of overweight and obesity to the health systems of developed countries.

Conclusion: The method presented here could be used to calculate the costs of overweight and obesity in other countries. Public health initiatives are required to address the increasing prevalence of overweight and obesity and reduce associated healthcare costs.

The North-South gap in overweight and obesity in England

Regional differences in overweight and obesity levels in England have mirrored those of CVD, with higher levels in the North. It is unclear whether the increase in the prevalence of overweight and obesity over the last 15 years has been consistent in different regions of the country. BMI data from each of the health surveys for England conducted between 1993 and 2004 were analysed. Annual grouped estimates of the prevalence of overweight (BMI ≤ 25 kg/m²) and obesity (BMI ≤ 30 kg/m²) for the North and the South of England were produced by appropriately combining regional administrative authorities. Logistic regression analyses were performed to assess the independence of the geographical effect after adjustment for age and social class. The prevalence of both overweight and obesity in women has risen more quickly in the North than in the South between 1993 and 2004, leading to a widening of inequalities. The prevalence of both overweight and obesity in women in the South has remained reasonably stable since 1997. The prevalence rates of both conditions in men have risen in parallel in the North and the South between 1993 and 2004 by approximately 8%. The OR for obesity for young women increased between 1993/98 and 1998/2004 from 1·07 (1·00, 1·14) to 1·21 (1·13, 1·30). Widening geographical inequalities in overweight and obesity rates in women could lead to widening inequalities in cardiovascular and other diseases.

The effectiveness of physical activity interventions for the treatment of overweight and obesity and type 2 diabetes

This review summarises current evidence relating to the effectiveness of physical activity (PA) interventions for treating overweight and obesity and type 2 diabetes. Interventions to increase PA for the treatment of overweight and obesity in both children and adults have primarily consisted of health education and behaviour modification strategies in clinical settings or with selected families or individuals. Although evidence is limited, strategies to reduce sedentary behaviours appear to have potential for reducing obesity among children and adolescents. Among adults, strategies that combine diet and PA are more effective than PA strategies alone. Combined lifestyle strategies are most successful for maintained weight loss, although most programs are unsuccessful in producing long-term changes. There is little evidence about compliance to prescribed behaviour changes or the factors that promote or hinder compliance to lifestyle changes. Limited evidence suggests that continued professional contact and self-help groups can help sustain weight loss. Most of the interventions for the treatment of type 2 diabetes have been conducted in clinical settings and have typically required the use of extensive resources. Evidence suggests that interventions can lead to small but clinically meaningful improvements in glycaemic control, even in the absence of weight loss. A recent study demonstrated that a multifactorial intervention (diet, PA and pharmaceutical) can reduce the risk of diabetes complications in individuals with type 2 diabetes. Nevertheless, there is little evidence about the effectiveness of community-based interventions in producing long-term changes in glycaemic control and reduced mortality in people with type 2 diabetes.

A preliminary analysis of barriers, intentions, and attitudes towards moderate physical activity in women who are overweight

Physical activity is important for the health of all individuals, however, the determinants of physical activity behaviour for women who are overweight remain largely unexplored. The purpose of this investigation was to explore a range of factors that influence participation in physical activity for a group of women who are overweight. Participants were 30 women, aged 25–71 years, with a mean age of 46.8 years (+12.95) and an average BMI of 31.2 kg/m2 (+5.6). Self-reported level of physical activity, perceived barriers and facilitators of physical activity, attitudes, intentions and perceived behavioural control to physical activity were measured. Seventeen participants were generally active, with self-reported moderate physical activity of 218.53 min (±113.82) in the last 7 days; whereas 13 participants were reportedly less active 43.46 (±42.98) min. Active participants were more likely to identify social reasons for participating in physical activity, while inactive participants perceived that their laziness prevented them from being physically active. There were no significant differences between active and inactive overweight women for attitude, intention or subjective norm for moderate-intensity physical activity. There was a significant difference between these women in perceived behavioural control (p = .014) for moderate-intensity physical activity, as women who felt more in control of their physical activity behaviour were more likely to engage in physical activity than inactive women. Future research should investigate interventions to increase behavioural control of moderate-intensity physical activity in women who are overweight.