How does age affect the relationship between weight and health utility during the middle years of childhood?

Association of body mass index from childhood to mid-adulthood with health-related quality of life in mid-adulthood

PURPOSE

Most studies regarding the association of obesity with health-related quality of life (HRQoL) have assessed obesity at only one or two time points. We aimed to examine the associations of life course body mass index (BMI) from childhood with health-related quality of life (HRQoL) in mid-adulthood.

METHODS

Data were from a cohort study of Australian children (n = 2254, mean baseline age 12.0 (2.0) years in 1985, 46.8% male). Weight and height were measured at baseline and measured or self-reported on average 20, 25, and 30 years later. Age and sex-standardised BMI-z score was calculated at each time point. Physical and mental HRQoL and health state utilities (HSUs) were measured by SF-12 and SF-6D at the last adult follow-up. Linear regression was used to examine the associations adjusting for age, sex, and childhood health status.

RESULTS

Higher BMI-z score in childhood (βadjusted - 1.39, 95% CI - 1.73 to - 1.05) and increasing BMI-z score from childhood to young adulthood (βadjusted - 1.82, 95% CI - 2.17 to - 1.46) and from young to mid-adulthood (βadjusted - 1.77, 95% CI - 2.28 to - 1.26) were associated with lower physical HRQoL in mid-adulthood. Similar results were found for mid-adulthood HSUs (βadjusted ranged - 0.006 to - 0.014, all P < 0.05). Only increasing BMI-z score from young to mid-adulthood significantly related to poorer mental HRQoL (βadjusted - 0.74, 95% CI - 1.29 to - 0.19) in mid-adulthood.

CONCLUSION

High BMI from childhood to mid-adulthood had only modest associations with HRQoL and HSUs, with effects on physical HRQoL most apparent.

Reliability, acceptability, validity and responsiveness of the CHU9D and PedsQL in the measurement of quality of life in children and adolescents with overweight and obesity

BACKGROUND

The Paediatric Quality of life Inventory (PedsQL^TM) Generic Core Scales and the Child Health Utilities 9 Dimensions (CHU9D) are two paediatric health-related quality of life (HRQoL) measures commonly used in overweight and obesity research. However, no studies have comprehensively established the psychometric properties of these instruments in the context of paediatric overweight and obesity. The aim of this study was to assess the reliability, acceptability, validity and responsiveness of the PedsQL and the CHU9D in the measurement of HRQoL among children and adolescents living with overweight and obesity.

SUBJECTS/METHODS

Subjects were 6544 child participants of the Longitudinal Study of Australian Children, with up to 3 repeated measures of PedsQL and CHU9D and aged between 10 and 17 years. Weight and height were measured objectively by trained operators, and weight status determined using World Health Organisation growth standards. We examined reliability, acceptability, known group and convergent validity and responsiveness, using recognised methods.

RESULTS

Both PedsQL and CHU9D demonstrated good internal consistency reliability, and high acceptability. Neither instrument showed strong convergent validity, but PedsQL appears to be superior to the CHU9D in known groups validity and responsiveness. Compared with healthy weight, mean (95%CI) differences in PedsQL scores for children with obesity were: boys -5.6 (-6.2, -4.4); girls -6.7 (-8.1, -5.4) and differences in CHU9D utility were: boys -0.02 (-0.034, -0.006); girls -0.035 (-0.054, -0.015). Differences in scores for overweight compared with healthy weight were: PedsQL boys -2.2 (-3.0, -1.4) and girls -1.3 (-2.0, -0.6) and CHU9D boys: no significant difference; girls -0.014 (-0.026, -0.003).

CONCLUSION

PedsQL and CHU9D overall demonstrated good psychometric properties, supporting their use in measuring HRQoL in paediatric overweight and obesity. CHU9D had poorer responsiveness and did not discriminate between overweight and healthy weight in boys, which may limit its use in economic evaluation.

Is the cost-effectiveness of an early-childhood sleep intervention to prevent obesity affected by socioeconomic position?

OBJECTIVE

This study aimed to determine whether the cost-effectiveness of an infant sleep intervention from the Prevention of Overweight in Infancy (POI) trial was influenced by socioeconomic position (SEP).

METHODS

An SEP-specific economic evaluation of the sleep intervention was conducted. SEP-specific intervention costs and effects at age 5 years, derived from the trial data, were applied to a representative cohort of 4,898 4- to 5-year-old Australian children. Quality-adjusted life years and health care costs were simulated until age 17 years using a purpose-built SEP-specific model. Incremental cost-effectiveness ratios and acceptability curves were derived for each SEP group.

RESULTS

The incremental cost-effectiveness ratios, in Australian dollars per quality-adjusted life year gained, were smaller in the low- ($23,010) and mid-SEP ($18,206) groups compared with the high-SEP group ($31,981). The probability that the intervention was cost-effective was very high in the low- and mid-SEP groups (92%-100%) and moderately high in the high-SEP group (79%).

CONCLUSIONS

An infant sleep intervention is more cost-effective in low- and mid-SEP groups compared with high-SEP groups. Targeting this intervention to low-SEP groups would not require trade-offs between efficiency and equity.

Methods for the economic evaluation of obesity prevention dietary interventions in children: A systematic review and critical appraisal of the evidence

OBJECTIVES

We aim to describe and provide a discussion of methods used to conduct economic evaluations of dietary interventions in children and adolescents, including long-term modelling, and to make recommendations to assist health economists in the design and reporting of such evaluations.

METHODS

A systematic review was conducted in 11 bibliographic databases and the grey literature with searches undertaken between January 2000 and December 2021. A study was included if it (1) was an economic evaluation or modelling study of an obesity-prevention dietary intervention and (2) targeted 2- to 18-year-olds.

RESULTS

Twenty-six studies met the inclusion criteria. Twelve studies conducted an economic evaluation alongside a clinical trial, and 14 studies modelled long-term health and cost outcomes. Four overarching methodological challenges were identified: modelling long-term impact of interventions, measuring and valuing health outcomes, cost inclusions and equity considerations.

CONCLUSIONS

Variability in methods used to predict, measure and value long-term benefits in adulthood from short-term clinical outcomes in childhood was evident across studies. Key recommendations to improve the design and analysis of future economic evaluations include the consideration of weight regain and diminishing intervention effects within future projections; exploration of wider intervention benefits not restricted to quality-of-life outcomes; and inclusion of parental or caregiver opportunity costs.

Health Economic Aspects of Childhood Excess Weight: A Structured Review

An economic perspective is crucial to understand the broad consequences of childhood excess weight (CEW). These can manifest in the form of elevated health care and societal costs, impaired health status, or inefficiencies in the allocation of resources targeted at its prevention, management, or treatment. Although existing systematic reviews provide summaries of distinct economic research strands covering CEW, they have a restricted focus that overlooks relevant evidence. The overarching aim of this structured review was to update and enhance recent key reviews of four strands of economic evidence in this area, namely, (1) economic costs associated with CEW, (2) health utilities associated with CEW, (3) economic evaluations of interventions targeting CEW, and (4) economic determinants and broader consequences of CEW. Our de novo searches identified six additional studies for the first research strand, five studies for the second, thirty-one for the third, and two for the fourth. Most studies were conducted in a small number of high-income countries. Our review highlights knowledge gaps across all the research strands. Evidence from this structured review can act as data input into future economic evaluations in this area and highlights areas where future economic research should be targeted.

Relationship Between Weight Status and Health-Related Quality of Life in School-age Children in China

Background: Some studies from high-income countries suggest that overweight and/or obesity in children are negatively associated with health-related quality of life (HRQOL). However, the relationship between weight status and HRQOL is not well established in China, where obesity trends follow a different pattern compared with high-income countries. The risk of obesity is greater in children from higher socioeconomic backgrounds and higher in boys compared with girls. Objective: The aim of this study was to examine the relationship between weight status and HRQOL in children between 6 and 7 years old in this unique country context. Methods: Baseline HRQOL and demographic data were collected from children recruited to the CHIRPY DRAGON obesity prevention trial in China. HRQOL was measured using the Chinese version of the Child Health Utility-9D (CHU-9D-CHN) and the Pediatric Quality of Life Inventory™ (PedsQL™) instruments. CHU-9D-CHN utility scores were generated using 2 scoring algorithms (UK and Chinese tariffs). Height and weight measures were taken at school by trained researchers using standardized methods, and BMI z scores were calculated using the World Health Organization 2007 growth charts. The relationship between HRQOL and weight status was examined using multivariable analyses, adjusting for age, gender, and socioeconomic status. Results: Full data were available for 1539 children (mean age, 6 years). In both unadjusted and adjusted analyses, HRQOL, using both the CHU-9D-CHN and the PedsQL™, was marginally higher in children who were overweight or living with obesity compared with children with healthy weight, although this difference did not reach statistical significance. Separate analyses and models by gender showed that the relationship between weight status and HRQOL scores was similar in boys and girls. Conclusions: Our results suggest no statistically significant difference in HRQOL between children with overweight/obesity compared with those with healthy weight. These results have implications for the methods of economic evaluation for obesity treatment and prevention interventions within this population cohort and country setting, as there appears to be no discernible consequences on children's HRQOL from living with overweight and obesity.

Peer-led physical activity intervention for girls aged 13 to 14 years: PLAN-A cluster RCT

Background

Increasing physical activity among girls is a public health priority. Peers play a central role in influencing adolescent behaviour. Peer-led interventions may increase physical activity in adolescent girls, and a feasibility trial had shown that PLAN-A (Peer-led physical Activity iNtervention for Adolescent girls) had evidence of promise to increase physical activity in adolescent girls.

Objective

The objective was to test whether or not PLAN-A can increase adolescent girls’ physical activity, relative to usual practice, and be cost-effective.

Design

This was a two-arm, cluster-randomised controlled trial, including an economic evaluation and a process evaluation.

Participants

State-funded secondary schools in the UK with girls in Year 9 (aged 13–14 years) participated in the trial. All Year 9 girls in participating schools were eligible.

Randomisation

Schools were the unit of allocation. They were randomised by an independent statistician, who was blinded to school identities, to the control or intervention arm, stratified by region and the England Index of Multiple Deprivation score.

Intervention

The intervention comprised peer nomination (i.e. identification of influential girls), train the trainers (i.e. training the instructors who delivered the intervention), peer supporter training (i.e. training the peer-nominated girls in techniques and strategies underpinned by motivational theory to support peer physical activity increases) and a 10-week diffusion period.

Outcomes

The primary outcome was accelerometer-assessed mean weekday minutes of moderate to vigorous physical activity among Year 9 girls. The follow-up measures were conducted 5–6 months after the 10-week intervention, when the girls were in Year 10 (which was also 12 months after the baseline measures). Analysis used a multivariable, mixed-effects, linear regression model on an intention-to-treat basis. Secondary outcomes included weekend moderate to vigorous physical activity, and weekday and weekend sedentary time. Intervention delivery costs were calculated for the economic evaluation.

Results

A total of 33 schools were approached; 20 schools and 1558 pupils consented. Pupils in the intervention arm had higher Index of Multiple Deprivation scores than pupils in the control arm. The numbers randomised were as follows: 10 schools (n = 758 pupils) were randomised to the intervention arm and 10 schools (n = 800 pupils) were randomised to the control arm. For analysis, a total of 1219 pupils provided valid weekday accelerometer data at both time points (intervention, n = 602; control, n = 617). The mean weekday moderate to vigorous physical activity was similar between groups at follow-up. The central estimate of time spent engaging in moderate to vigorous physical activity was 2.84 minutes lower in the intervention arm than in the control arm, after adjustment for baseline mean weekday moderate to vigorous physical activity, the number of valid days of data and the stratification variables; however, this difference was not statistically significant (95% confidence interval –5.94 to 0.25; p = 0.071). There were no between-arm differences in the secondary outcomes. The intervention costs ranged from £20.85 to £48.86 per pupil, with an average cost of £31.16.

Harms

None.

Limitations

The trial was limited to south-west England.

Conclusions

There was no evidence that PLAN-A increased physical activity in Year 9 girls compared with usual practice and, consequently, it was not cost-effective.

Future work

Future work should evaluate the utility of whole-school approaches to promote physical activity in schools.

Trial registration

This trial is registered as ISRCTN14539759.

Funding

This project was funded by the National Institute for Health Research (NIHR) Public Health Research programme and will be published in full in Public Health Research; Vol. 10, No. 6. See the NIHR Journals Library website for further project information. This trial was designed and delivered in collaboration with the Bristol Randomised Trials Collaboration (BRTC), a United Kingdom Clinical Research Commission (UKCRC)-registered Clinical Trials Unit that, as part of the Bristol Trials Centre, is in receipt of NIHR Clinical Trials Unit support funding. The sponsor of this trial was University of Bristol, Research and Enterprise Development www.bristol.ac.uk/red/. The costs of delivering the intervention were funded by Sport England.

Weight status and health-related quality of life during childhood and adolescence: effects of age and socioeconomic position

BACKGROUND

Overweight and obesity in children is associated with poor health-related quality of life (HRQoL), but the nuances of this relationship across different age and socio-demographic groups are not well-established. The aim of this study is to examine how the association between weight status and HRQoL changes with age and socioeconomic position (SEP) throughout childhood and adolescence.

METHODS

We used data from the Longitudinal Study of Australian Children (LSAC), a cohort study in which children were interviewed biennially from ages 4 to 17 years over seven waves of data. Measurements of HRQoL (using PedsQL^TM), body mass index (BMI), and socio-demographic characteristics were collected at each interview. Of the 4983 children recruited into the study, we included data from 4083 children (a total of 24,446 observations). We used generalised estimating equations to assess whether age and SEP modified the association between weight status and HRQoL, after controlling for sex, long-term medical condition, language spoken to child and maternal smoking status.

RESULTS

Age was a significant modifier of the association between weight status and HRQoL, with adjustment for known predictors of HRQoL (P < 0.001). At age 4, children with obesity had, on average, a 0.99 (95% CI 0.02-1.96) point lower PedsQL total score than children at healthy weight. This difference became clinically important by age 9 at 4.50 (95% CI 3.86-5.13) points and increased to 6.69 (95% CI 5.74-7.64) points by age 17. There was no evidence that SEP modified the relationship between weight status and HRQoL (P > 0.05).

CONCLUSIONS

Our results demonstrate that the relationship between overweight and obesity status and poor HRQoL is strengthened with increasing age through childhood and adolescence, but is not affected by SEP. Paediatricians, researchers and carers of children with obesity should acknowledge HRQoL outcomes, particularly for older children and adolescents.

Economic evaluation of a childhood obesity prevention programme for children: Results from the WAVES cluster randomised controlled trial conducted in schools

Background

Childhood obesity is a serious public health challenge and schools have been identified as an ideal place to implement prevention interventions. The aim of this study was to measure the cost-effectiveness of a multi-faceted school-based obesity prevention intervention targeting children aged 6–7 years when compared to ‘usual activities’.

Methods

A cluster randomised controlled trial in 54 schools across the West Midlands (UK) was conducted. The 12-month intervention aimed to increase physical activity by 30 minutes per day and encourage healthy eating. Costs were captured from a public sector perspective and utility-based health related outcomes measured using the CHU-9D. Multiple imputation using chained equations was used to address missing data. The cost effectiveness was measured at 30 months from baseline using a hierarchical net-benefit regression framework, that controlled for clustering and prespecified covariates. Any uncertainty in the results was characterised using cost-effectiveness acceptability curves.

Results

At 30 months, the total adjusted incremental mean cost of the intervention was £155 (95% confidence interval [CI]: £139, £171), and the incremental mean QALYs gained was 0.006 (95% CI: -0.024, 0.036), per child. The incremental cost-effectiveness at 30 months was £26,815 per QALY and using a standard willingness to pay threshold of £30,000 per QALY, there was a 52% chance that the intervention was cost-effective.

Conclusions

The cost-effectiveness of the school-based WAVES intervention was subject to substantial uncertainty. We therefore recommend more research to explore obesity prevention within schools as part of a wider systems approach to obesity prevention.

Trial registration

This paper uses data collected by the WAVES trial: Controlled trials ISRCTN97000586 (registered May 2010).

Introducing physically active lessons in UK secondary schools: feasibility study and pilot cluster-randomised controlled trial

OBJECTIVES

Assess feasibility, acceptability and costs of delivering a physically active lessons (PAL) training programme to secondary school teachers and explore preliminary effectiveness for reducing pupils' sedentary time.

DESIGN AND SETTING

Secondary schools in East England; one school participated in a pre-post feasibility study, two in a pilot cluster-randomised controlled trial. In the pilot trial, blinding to group assignment was not possible.

PARTICIPANTS

Across studies, 321 randomly selected students (51% male; mean age: 12.9 years), 78 teachers (35% male) and 2 assistant head teachers enrolled; 296 (92%) students, 69 (88%) teachers and 2 assistant head teachers completed the studies.

INTERVENTION

PAL training was delivered to teachers over two after-school sessions. Teachers were made aware of how to integrate movement into lessons; strategies included students collecting data from the environment for class activities and completing activities posted on classroom walls, instead of sitting at desks.

PRIMARY AND SECONDARY OUTCOMES

Quantitative and qualitative data were collected to assess feasibility and acceptability of PAL training and delivery. Outcomes were assessed at baseline and ~8 weeks post-training; measures included accelerometer-assessed activity, self-reported well-being and observations of time-on-task. Process evaluation was conducted at follow-up.

RESULTS

In the feasibility study, teachers reported good acceptability of PAL training and mixed experiences of delivering PAL. In the pilot study, teachers' acceptability of training was lower and teachers identified aspects of the training in need of review, including the outdoor PAL training and learning challenge of PAL strategies. In both studies, students and assistant head teachers reported good acceptability of the intervention. Preliminary effectiveness for reducing students' sedentary time was not demonstrated in either study.

CONCLUSIONS

No evidence of preliminary effectiveness on the primary outcome and mixed reports of teachers' acceptability of PAL training suggest the need to review the training. The results do not support continuation of research with the current intervention.

TRIAL REGISTRATION NUMBER

ISRCTN38409550.