Health-related quality of life in obese children and adolescents

Objective: This review addresses the effect of overweight and obese weight status on pediatric health-related quality of life (HRQOL). Method: Web of Science, Medline, CINAHL, Cochrane Library, EMBASE, AMED and PubMed were searched for peer-reviewed studies in English reporting HRQOL and weight status in youth (<21 years), published before March 2008. Results: Twenty-eight articles were identified. Regression of HRQOL against body mass index (BMI) using pooled data from 13 studies utilizing the Pediatric Quality of Life Inventory identified an inverse relationship between BMI and pediatric HRQOL (r=−0.7, P=0.008), with impairments in physical and social functioning consistently reported. HRQOL seemed to improve with weight loss, but randomized controlled trials were few and lacked long-term follow-up. Conclusions: Little is known about the factors associated with reduced HRQOL among overweight or obese youth, although gender, age and obesity-related co-morbidities may play a role. Few studies have examined the differences in HRQOL between community and treatment-seeking samples. Pooled regressions suggest pediatric self-reported HRQOL can be predicted from parent proxy reports, although parents of obese youths tend to perceive worse HRQOL than children do about themselves. Thus, future research should include both pediatric and parent proxy perspectives.

Indexes of insulin resistance and secretion in obese children and adolescents : a validation study

OBJECTIVE To assess the concurrent validity of fasting indexes of insulin sensitivity and secretion in - obese prepubertal (Tanner stage 1) children and pubertal (Tanner stages 2-5) glucose tolerance test (FSIVGTT) as a criterion measure. RESEARCH DESIGN AND METHODS Eighteen obese children and adolescents (11 girls and 7 boys, mean age 12.2 +/- 2.4 years, mean BMI 35.4 +/- 6.2 kg/m(2), mean BMI-SDS 3.5 +/- 0.5, 7 prepubertal and I I pubertal) participated in the study. All participants underwent an insulin-modified FSIVGTT on two occasions, and 15 repeated this test a third time (mean 12.9 and 12.0 weeks apart). S-i measured by the FSIVGTT was compared with homeostasis model assessment (HOMA) of insulin resistance (HOMA-IR), quantitative insulin-sensitivity check index (QUICKI), fasting glucose-to-insulin ratio (FGIR), and fasting insulin (estimates of insulin sensitivity derived from fasting samples). The acute insulin response (AIR) measured by the FSIVGTT was compared with HOMA of percent beta-cell function (HOMA-beta%), FGIR, and fasting insulin (estimates of insulin secretion derived from fasting samples). RESULTS There was a significant negative correlation between HOMA-IR and S-i (r = -0.89, r = -0.90, and r = -0.81, P < 0.01) and a significant positive correlation between QUICKI and S-i (r = 0.89, r = 0.90, and r = 0.81, P < 0.01) at each time point. There was a significant positive correlation between FGIR and S-i (r = 0.91, r = 0.91, and r = 0.82, P < 0.01) and a significant negative correlation between fasting insulin and S-i (r = -90, r = -0.90, and r = -0.88, P < 0.01). HOMA-beta% was not as strongly correlated with AIR (r = 0.60, r = 0.54, and r = 0.61, P < 0.05). CONCLUSIONS HOMA-IR, QUICKI, FGIR, and fasting insulin correlate strongly with S-i assessed by the FSIVGTT in obese children and adolescents. Correlations between HOMA-β% FGIR and fasting insulin, and AIR were not as strong. Indexes derived from fasting samples are a valid tool for assessing insulin sensitivity in prepubertal and pubertal obese children.

Physical activity and determinants of physical activity in obese and non-obese children

OBJECTIVE To compare the physical activity (PA) patterns and the hypothesized psychosocial and environmental determinants of PA in an ethnically diverse sample of obese and non-obese middle school children. DESIGN Cross-sectional study. SUBJECTS One-hundred and thirty-three non-obese and 54 obese sixth grade children (mean age of 11.4 +/-0.6). Obesity status determined using the age-, race- and gender-specific 95th percentile for BMI from NHANES-1. MEASUREMENTS Objective measurements were collected of PA over a 7-day period using the CSA 7164 accelerometer: total daily counts; daily moderate (3-5.9 METs) physical activity (MPA); daily vigorous physical activity (greater than or equal to 6 METs; VPA); and weekly number of 5, 10 and 20 min bouts of moderate-to-vigorous physical activity (greater than or equal to 3 METs, MVPA). Self-report measures were collected of PA self-efficacy; social influences regarding PA, beliefs about PA outcomes; perceived PA levels of parents and peers, access to sporting and/or fitness equipment at home, involvement in community-based PA organizations; participation in community sports teams; and hours spent watching television or playing video games. RESULTS Compared to their non-obese counterparts, obese children exhibited significantly lower daily accumulations of total counts, MPA and VPA as well as significantly fewer 5, 10 and 20 min bouts of MVPA. Obese children reported significantly lower levels of PA self-efficacy, were involved in significantly fewer community organizations promoting PA and were significantly less likely to report their father or male guardian as physically active. CONCLUSIONS The results are consistent with the hypothesis that physical inactivity is an important contributing factor in the maintenance of childhood obesity. Interventions to promote PA in obese children should endeavor to boost self-efficacy perceptions regarding exercise, increase awareness of, and access to, community PA outlets, and increase parental modeling of PA.

The feasibility of a home-based moderate-intensity physical activity intervention in obese children and adolescents

Objective To explore the feasibility of conducting a 10-week home-based physical activity (PA) programme and evaluate the changes in insulin sensitivity (S I) commensurate with the programme in obese young people. Design Open-labelled intervention. Setting Home-based intervention with clinical assessments at a tertiary paediatric hospital. Subjects 18 obese (body mass index (BMI)>International Obesity Task Force age and sex-specifi c cut-offs) children and adolescents (8-18 years, 11 girls/7 boys) were recruited. 15 participants (nine girls/six boys, mean±SE age 11.8±0.6 years, BMI-SD scores (BMI-SDS) 3.5±0.1, six prepubertal/nine pubertal) completed the intervention. Intervention The programme comprised biweekly home visits over 10 weeks with personalised plans implemented aiming to increase moderate-intensity PA. Pedometers and PA diaries were used as self-monitoring tools. The goals were to (1) teach participants behavioural skills related to adopting and maintaining an active lifestyle and (2) increase daily participation in PA. Outcome measures Mean steps/day were assessed. SI assessed by the frequently sampled intravenous glucose tolerance test and other components of the insulin resistance syndrome were measured. Results Mean steps/day increased significantly from 10 363±927 (baseline) to 13 013±1131 (week 10) (p<0.05). S I was also significantly increased, despite no change in BMI-SDS, and remained so after an additional 10-week follow-up. Conclusions The results suggest that such a homebased PA programme is feasible. S I improved without changes in BMI-SDS. More rigorous evaluations of such programmes are warranted.

Inflammatory Markers and Obstructive Sleep Apnea in Obese Children: The NANOS Study

Introduction. Obesity and obstructive sleep apnea syndrome (OSA) are common coexisting conditions associated with a chronic low-grade inflammatory state underlying some of the cognitive, metabolic, and cardiovascular morbidities. Aim. To examine the levels of inflammatory markers in obese community-dwelling children with OSA, as compared to no-OSA, and their association with clinical and polysomnographic (PSG) variables. Methods. In this cross-sectional, prospective multicenter study, healthy obese Spanish children (ages 4-15 years) were randomly selected and underwent nocturnal PSG followed by a morning fasting blood draw. Plasma samples were assayed for multiple inflammatory markers. Results. 204 children were enrolled in the study; 75 had OSA, defined by an obstructive respiratory disturbance index (RDI) of 3 events/hour total sleep time (TST). BMI, gender, and age were similar in OSA and no-OSA children. Monocyte chemoattractant protein-1 (MCP-1) and plasminogen activator inhibitor-1 (PAI-1) levels were significantly higher in OSA children, with interleukin-6 concentrations being higher in moderate-severe OSA (i.e., AHI > 5/hrTST; P < 0.01), while MCP-1 levels were associated with more prolonged nocturnal hypercapnia (P < 0.001). Conclusion. IL-6, MCP-1, and PAI-1 are altered in the context of OSA among community-based obese children further reinforcing the proinflammatory effects of sleep disorders such as OSA. This trial is registered with ClinicalTrials.gov NCT01322763.

Self-perception in overweight and obese children: a cross-sectional study

Aim The aim of this study was to examine the relationship between obesity and self-esteem in children in relation to specific domains of their self-perception, and further to explore the extent to which this may vary by gender and economic circumstances. Method A total of 211 children aged 8–9 years drawn from both advantaged and disadvantaged areas of Belfast completed the Harter Self-Perception Profile for Children and measures of body mass index were obtained. Results Overweight, impoverished children had significantly reduced social acceptance and physical competence scores. Boys had significantly lower scores than girls in the behavioural conduct domain. Girls had significantly lower scores than boys for the athletic competence. Conclusion These results suggest that risk factors of increased weight and impoverished backgrounds have a combined negative effect, placing some children at increased risk of having lower self-perceptions in some, but not all domains. Health interventions for childhood obesity should consider the likelihood of specific relationships between physical and psychosocial factors.

High-density lipoprotein subfractions display proatherogenic properties in overweight and obese children

BACKGROUND: In adults, obesity-driven inflammation can lead to increased cardiovascular disease (CVD). However, information regarding childhood obesity and its inflammatory sequelae is less well defined. Serum amyloid-A (SAA) is an inflammatory molecule that rapidly associates with high-density lipoproteins (HDLs) and renders them dysfunctional. Therefore, SAA may be a useful biomarker to identify increased CVD potential in overweight and obese children.

METHODS: Young Hearts 2000 is a cross-sectional cohort study in which 92 children who were obese were matched for age and sex with 92 overweight and 92 lean children. HDL2 and HDL3 (HDL2&3) were isolated from plasma by a three-step rapid-ultracentrifugation procedure. SAA was measured in serum and HDL2&3 by an enzyme-linked immunosorbent assay procedure, and the activities of cholesterol ester transfer protein (CETP) and lecithin cholesteryl acyltransferase (LCAT) were measured by fluorimetric assays.

RESULTS: Trends across the groups indicated that SAA increased in serum and HDL2&3 as BMI increased, as did HDL2-CETP and HDL2-LCAT activities.

CONCLUSION: These results have provided evidence that overweight and obese children are exposed to an inflammatory milieu that impacts the antiatherogenic properties of HDL and that could increase CVD risk. This supports the concept that it is important to target childhood obesity to help minimize future cardiovascular events.

Health-related quality of life of overweight and obese children

Context: The negative effects of childhood overweight and obesity on quality of life (QOL) have been shown in clinical samples but not yet in population-based community samples.

Objective: To determine relationships between weight and health-related QOL reported by parent-proxy and child self-report in a population sample of elementary school children.

Design, Setting, and Participants: Cross-sectional data collected in 2000 within the Health of Young Victorians Study, a longitudinal cohort study commenced in 1997. Individuals were recruited via a random 2-stage sampling design from primary schools in Victoria, Australia. Of the 1943 children in the original cohort, 1569 (80.8%) were resurveyed 3 years later at a mean age of 10.4 years.

Main Outcome Measures: Health-related QOL using the PedsQL 4.0 survey completed by both parent-proxy and by child self-report. Summary scores for children'S total, physical, and psychosocial health and subscale scores for emotional, social, and school functioning were compared by weight category based on International Obesity Task Force cut points.

Results: Of 1456 participants, 1099 (75.5%) children were classified as not overweight; 294 (20.2%) overweight; and 63 (4.3%) obese. Parent-proxy and child self-reported PedsQL scores decreased with increasing child weight. The parent-proxy total PedsQL mean (SD) score for children who were not overweight was 83.1 (12.5); overweight, 80.0 (13.6); and obese, 75.0 (14.5); P < .001. The respective child self-reported total PedsQL mean (SD) scores were 80.5 (12.2), 79.3 (12.8), and 74.0 (14.2); P < .001. At the subscale level, child and parent-proxy reported scores were similar, showing decreases in physical and social functioning for obese children compared with children who were not overweight (all P < .001). Decreases in emotional and school functioning scores by weight category were not significant.

Conclusion: The effects of child overweight and obesity on health-related QOL in this community-based sample were significant but smaller than in a clinical sample using the same measure.

Economic Evaluation of a Primary Care Trial to Reduce Weight Gain in Overweight/Obese Children: The LEAP Trial

Background:- A common policy response to the childhood obesity epidemic is to recommend that primary care physicians screen for and offer counseling to the overweight/obese. As the literature suggests, this approach may be ineffective; it is important to document the opportunity costs incurred by brief primary care obesity interventions that ultimately may not alter body mass index (BMI) trajectory.

Methods:- Live, Eat and Play (LEAP) was a randomized controlled trial of a brief secondary prevention intervention delivered by family physicians in 2002-2003 that targeted overweight/ mildly obese children aged 5 to 9 years. Primary care utilization was prospectively audited via medical records, and parents reported family resource use by written questionnaire. Outcome measures were BMI (primary) and parent-reported physical activity and dietary habits (secondary) in intervention compared with control children.

Results:- The cost of LEAP per intervention family was AU $4094 greater than for control families, mainly due to increased family resources devoted to child physical activity. Total health sector costs were AU $873 per intervention family and AU $64 per control, a difference of AU $809 {P < .001). At 15 months, intervention children did not differ significantly in adjusted BMI or daily physical activity scores compared with the control group, but dietary habits had improved.

Conclusions:- This brief intervention resulted in higher costs to families and the health care sector, which could have been devoted to other uses that do create benefits to health and/or family well-being. This has implications for countries such as the United States, the United Kingdom, and Australia, whose current guidelines recommend routine surveillance and counseling for high child BMI in the primary care sector.

Cost-effectiveness of a family-based GP-mediated intervention targeting overweight and moderately obese children

Objective
 To assess from a societal perspective the incremental cost-effectiveness of a family-based GP-mediated intervention targeting overweight and moderately obese children. The intervention was modelled on the LEAP (live, eat and play) trial, a randomised controlled trial conducted by the Centre for Community Child Health, Melbourne, Australia in 2002–2003. This study was undertaken as part of the assessing cost-effectiveness (ACE) in obesity project which evaluated, using consistent methods, 13 interventions targeting unhealthy weight gain in children and adolescents.
Method
A logic pathway was used to model the effects of the intervention compared to no intervention on body mass index (BMI) and health outcomes (disability-adjusted life years—DALYs). Disease costs and health benefits were tracked until the cohort of eligible children reached the age of 100 years or death. Simulation-modelling techniques were used to present a 95% uncertainty interval around the cost-effectiveness ratio. The intervention was also assessed against a series of filters (‘equity’, ‘strength of evidence’, ‘acceptability’, ‘feasibility’, sustainability’ and ‘side-effects’) to incorporate additional factors that impact on resource allocation decisions.
Results
The intervention, as modelled, reached 9685 children aged 5–9 years with a BMI z-score of ≥3.0, and cost $AUD6.3M (or $AUD4.8M excluding time costs). It resulted in an incremental saving of 2300 BMI units which translated to 511 DALYs. The cost-offsets stemming from the intervention totalled $AUD3.6M, resulting in a net cost per DALY saved of $AUD4670 (dominated; $0.1M) (dominated means intervention costs more for less effect).
Conclusion
Compared to a ‘no intervention’ control group, the intervention was cost-effective under current assumptions, although the uncertainty intervals were wide. A key question related to the long-term sustainability of the small incremental weight loss reported, based on the 9-month follow-up results for LEAP.

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.

Fractal correlation of heart rate variability in obese children

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)