A multilevel analysis of overweight and obesity among non-pregnant women of reproductive age in Malawi: evidence from the 2015-16 Malawi Demographic and Health Survey.

Background: Overweight and obesity are well-known risk factors for non-communicable diseases such as cardiovascular disease, diabetes, some cancers and musculoskeletal disorders. In Malawi, the proportion of women who are overweight/obese has doubled, from 10% in 1992 to 21% in 2015-16. Therefore we aimed to explore the individual- and community-level factors associated with overweight and obesity among non-pregnant women of child-bearing age.

Methods: Secondary analysis of the 2015-16 Malawi Demographic and Health Survey was conducted. Overweight was defined as a body mass index (BMI) of 25 to <30 kg/m2, while obesity was defined as a BMI ≥30 kg/m2. Two-level multilevel multivariable logistic regression models were constructed using a logit-link function with a binomial distribution on 7326 women living in 850 different communities.

Results: At the individual level, the adjusted multilevel regression results showed that women 15-19 y of age as well as women from the poorest households had reduced odds of being overweight/obese. However, women with white collar jobs and women who were affiliated with the Church of Central Africa Presbyterian and the Roman Catholic church had increased odds of being overweight/obese. At the community level, women from urban areas and women who resided in communities with a low percentage of media exposure had increased odds of being overweight or obese. While women from poor communities had reduced odds of being overweight and obese, the proportion change in variance showed that 56, 77 and 78% of total variations in the odds of overweight, obese and overweight/obese across the communities were explained by both individual- and community-level factors. The median odds ratio showed that the likelihood of maternal overweight, obese and overweight/obese increased by 63, 39 and 84% when the women moved from low- to high-risk neighbourhoods.

Conclusions: Older women, Christian women, women with white collar jobs and women from the richest households should be targeted during policy formulation. At the community level, media coverage should be spread evenly so that health awareness messages, consequences and means of overweight and obesity prevention are getting to the targeted women. Our study revealed evidence of clustering effects of overweight and obesity at the community level, hence neighbourhood variations with respect to maternal overweight and obesity should be taken into account when designing nutritional policies.