Effectiveness of physical activity and dietary interventions in South Asian populations: a systematic review.

BACKGROUND Physical activity and dietary change interventions can prevent or delay a range of chronic disease. Little is known in primary care about their effectiveness in South Asian populations, who are often at higher risk of developing such diseases. AIM To assess evidence for effectiveness of primary care based physical activity and dietary interventions in South Asian populations, and identify methods to inform future intervention development. DESIGN Systematic review. METHOD Intervention studies conducted in developed countries that reported data for South Asian adults were sought by searching electronic databases, trial registries, and conference proceedings. Following wider screening of titles and abstracts, 119 full articles were reviewed. RESULT Of the 119 articles, four studies met the inclusion criteria and evaluated community-based interventions with South Asian individuals. Methodological quality was poor overall. Interventions appeared generally effective in promoting a decrease in weight, with some positive changes in blood pressure and biochemical outcomes, such as cholesterol. There was limited evidence for effects on behaviour. Theoretical frameworks were not identified and evidence on attitudinal or knowledge-based outcomes was sparse. The inclusion of individual feedback and community workers in communities of deprivation appeared important to the acceptability of the interventions. Information distinguishable for South Asian individuals within intervention studies of general populations was lacking. CONCLUSION Physical activity and dietary interventions with South Asian populations show modest promise but, given the paucity of controlled evaluations or use of objective measures, outcomes are difficult to interpret. Potential insights may be missed if experience concerning South Asian groups within studies is not reported. Further development of culturally appropriate interventions that are theoretically informed and assessed in experimental designs are required.