Interventions to prevent or manage obesity in Māori and Pacific adults: a systematic review and narrative synthesis

Obesity and its sequelae are an increasing problem, disproportionally affecting Māori and Pacific peoples, secondary to multifactorial systemic causes, including the effects of colonisation and the impact of globalisation. There is limited synthesised evidence on interventions to address obesity in these populations. The objective of this review is to identify evaluated interventions for prevention and management of obesity amongst Māori and Pacific adults, assess the effectiveness of these interventions, and identify enablers and barriers to their uptake.

Systematic review of databases (Medline, PubMed, EMBASE, CINAHL, Scopus, CENTRAL), key non-indexed journals, and reference lists of included articles were searched from inception to June 2021. Eligibility criteria defined using a Population, Intervention, Control, Outcome format and study/publication characteristics. Quantitative and qualitative data were extracted and analysed using narrative syntheses. Study quality was assessed using modified GRADE approach.

From the 8190 articles identified, 21 were included, with 18 eligible for quantitative and five for qualitative analysis. The studies were heterogenous, with most graded as low quality. Some studies reported small but statistically significant improvements in weight and body mass index. Key enablers identified were social connection, making achievable sustainable lifestyle changes, culturally-centred interventions and incentives including money and enjoyment. Barriers to intervention uptake included difficulty in maintaining adherence to a programme due to intrinsic programme factors such as lack of social support and malfunctioning or lost equipment.

Normal weight trajectory is progressive increase over time. Modest weight loss or no weight gain after several years may have a positive outcome in lowering progression to diabetes, or improvement of glycaemic control in people with diabetes. We recommend urgent implementation of Māori and Pacific-led, culturally-tailored weight loss programmes that promote holistic, small and sustainable lifestyle changes delivered in socially appropriate contexts.