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Published on: February 2, 2017
Assessing the impact of obesity interventions in the early years: a systematic review of UK-based studies
Semina Michalopoulou1, Maria Sifaki2, Jessica Packer1
1Great Ormond Street Institute of Child Health, University College London, London, UK.
Insights
UK childhood obesity interventions show promise in early years. Despite limited evidence and high risk of bias, some studies significantly reduced z-score Body Mass Index (zBMI), suggesting potential for policy integration.
Area of Science:
- Public Health
- Pediatrics
- Evidence Synthesis
Background:
- Childhood obesity is a significant public health concern in the UK.
- Early childhood (6 months to 5 years) is a critical period for establishing lifelong healthy behaviors.
- Interventions during early childhood offer a key opportunity for obesity prevention.
Purpose of the Study:
- To systematically review UK-based obesity interventions for children aged 6 months to 5 years.
- To evaluate the impact of these interventions on anthropometric outcomes, primarily z-score Body Mass Index (zBMI).
- To identify effective strategies for early childhood obesity prevention.
Main Methods:
- Systematic review adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.
- Searched nine databases in March 2023, including studies published between 2011-2023.
- Included UK-based interventions with diet/physical activity components and anthropometric outcomes; excluded breastfeeding interventions as primary obesity prevention.
Main Results:
- Six trials (five studies) involving 566 children were identified.
- Five interventions reported reductions in zBMI from baseline; three were statistically significant.
- Compared to controls, five interventions showed zBMI reductions, with one significant finding. High risk of bias was noted across all studies.
- Meta-analysis was precluded by study heterogeneity.
Conclusions:
- Evidence on UK early childhood obesity interventions is limited but suggests potential benefits.
- Some interventions demonstrated promising results in promoting healthy growth trajectories.
- Early years interventions, as part of broader policy initiatives, may play a crucial role in mitigating childhood obesity risk.
Objectives:
Childhood obesity rates in the UK are high. The early years of childhood are critical for establishing healthy behaviours and offer interventional opportunities. We aimed to identify studies evaluating the impact of UK-based obesity interventions in early childhood.
Design:
Systematic review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.
Data Sources:
Nine databases were searched in March 2023.
Eligibility Criteria:
We included UK-based obesity intervention studies delivered to children aged 6 months to 5 years that had diet and/or physical activity components and reported anthropometric outcomes. The primary outcome of interest was z-score Body Mass Index (zBMI) change (within and between subjects). Studies evaluating the effects of breastfeeding interventions were not included as obesity prevention interventions, given that best-practice formula feeding is also likely to encourage healthy growth. The publication date for studies was limited to the previous 12 years (2011-23), as earlier reviews found few evaluations of interventions in the UK.
Data Extraction And Synthesis:
The reviewers worked independently using standardised approach to search, screen and code the included studies. Risk of bias was assessed using Cochrane tools (ROB 2 or ROBINS-I).
Results:
Six trials (five studies) were identified, including two randomised controlled trials (RCT), one cluster randomised trial (CRT), two feasibility CRTs and one impact assessment. The total number of participants was 566. Three trials focused on disadvantaged families and two included high-risk children categorised as having overweight or obesity. Compared with baseline, five interventions reported reductions in zBMI, three of which were statistically significant (p<0.05). Compared with control, five interventions showed zBMI reductions, one of which was significant. Only two trials were followed up beyond 12 months. All studies were found to have a high risk of bias. Meta-analysis was not possible due to the heterogeneity of studies.
Conclusion:
UK evidence was limited but some interventions showed promising results in promoting healthy growth. As part of a programme of policies, interventions in the early years may have an important role in reducing the risk of childhood obesity.
Prospero Registration Number:
CRD42021290676.
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