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. 2025 Mar 4:81:103130.
doi: 10.1016/j.eclinm.2025.103130. eCollection 2025 Mar.

Do the effects of interventions aimed at the prevention of childhood obesity reduce inequities? A re-analysis of randomized trial data from two Cochrane reviews

Jennifer C Palmer  1 , Annabel L Davies  1 , Francesca Spiga  1 , Berit L Heitmann  2   3 , Russell Jago  1   4 , Carolyn D Summerbell  5   6 , Julian P T Higgins  1   4 ; Inequity in Obesity Prevention Trialists Collaborative Group
Collaborators, Affiliations

Do the effects of interventions aimed at the prevention of childhood obesity reduce inequities? A re-analysis of randomized trial data from two Cochrane reviews

Jennifer C Palmer et al. EClinicalMedicine. .

Abstract

Background: Public health attempts to prevent obesity in children and young people should aim to minimize health inequalities. Two Cochrane reviews examining interventions aiming to prevent childhood obesity found that interventions promoting (only) physical activity have a small beneficial effect on BMI for people aged 5-18 years, as do interventions promoting physical activity alongside healthy eating for 5-11 year olds. We examined whether the effectiveness of the interventions included in these reviews differed according to eight factors associated with inequity: place, race/ethnicity, occupation, gender/sex, religion, education, socio-economic status, and social capital (the PROGRESS framework).

Methods: We collected data on change in BMI (standardized or unstandardized), subgrouped by baseline measures of PROGRESS factors, for intervention and control groups, from trial authors. We calculated the intervention effect per subgroup (mean difference), then contrasted these to estimate interactions between intervention and the baseline factors. We combined interaction estimates for each factor across trials using meta-analyses.

Findings: We collected subgrouped data from 81 trials that took place between 2001 and 2020, involving 84,713 participants. We found no substantial differences in effectiveness of interventions for PROGRESS subgroups in most scenarios. However, in the younger age group (5-11 years), the effect of interventions on standardized BMI appeared to be higher in boys (average difference in mean differences 0.03; 95% CI 0.01 to 0.06; 45 studies, n = 44,740), which was consistent in direction with the BMI effect (average difference in mean differences 0.06 kg/m2; 95% CI -0.02 to 0.13; 31 studies, n = 27,083).

Interpretation: Our findings suggest that those responsible for public health can promote these beneficial interventions without major concerns about increasing inequalities but should be mindful that these interventions may work better in boys aged 5-11 years than girls. More data are needed, so we encourage future trialists to perform subgroup analyses on PROGRESS factors.

Funding: National Institute for Health and Care Research (NIHR).

Keywords: Childhood obesity prevention; Health inequities; Meta-analysis.

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Conflict of interest statement

JCP, ALD, FS, RJ and JPTH were funded by grants from National Institute for Health and Care Research (NIHR) for this work. RJ also received funding from NIHR Applied Research Collaboration West and he is PI of a UKRI grant which does not directly relate to this work. JPTH received travel expenses funded by European Association for the Study of Obesity to give plenary talk at European Congress on Obesity in May 2023.

Figures

Fig. 1
Fig. 1
Trial selection process.
Fig. 2
Fig. 2
Summary of results for age- and sex-standardized BMI (zBMI): estimates of interaction, expressed as difference in intervention effect (itself expressed as a mean difference) between two inequity factor-based subgroups.
Fig. 3
Fig. 3
Summary of results for BMI: estimates of interaction, expressed as difference in intervention effect (itself expressed as a mean difference) between two inequity factor-based subgroups.
See this image and copyright information in PMC

References

    1. Commission on Ending Childhood Obesity . World Health Organization; Geneva: 2016. Report of the commission on ending childhood obesity.https://www.who.int/publications/i/item/9789241510066
    1. N. C. D. Risk Factor Collaboration Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults. Lancet. 2024;403(10431):1027–1050. - PMC - PubMed
    1. Lister N.B., Baur L.A., Felix J.F., et al. Child and adolescent obesity. Nat Rev Dis Primers. 2023;9(1):24. - PubMed
    1. Olsen N.J., Ostergaard J.N., Bjerregaard L.G., et al. A literature review of evidence for primary prevention of overweight and obesity in healthy weight children and adolescents: a report produced by a working group of the Danish Council on Health and Disease Prevention. Obes Rev. 2024;25(1) - PubMed
    1. UK Government Childhood obesity. POSTnote number 640, April 2021. London: the parliamentary office of science and technology. https://researchbriefings.files.parliament.uk/documents/POST-PN-0640/POS...