Association between body mass index (BMI) and hypertension in South Asian population: Evidence from Demographic and Health Survey

Although there has been a well-established association between adiposity and hypertension, whether such associations are heterogeneous for South Asian populations or for different socioeconomic groups is not well-known. We analysed the recent Demographic and Health Survey (DHS) data from Bangladesh, India, and Nepal to estimate the age-specific prevalence of hypertension and the association of body mass index (BMI) with hypertension. We used multiple logistic regressions to estimate the odds ratios (ORs) with 95% confidence intervals (CIs) of hypertension for overweight and obesity as well as for each 5-unit increase in BMI. The overall prevalence for hypertension among participants aged 35-44 years were 17.4%, 20%, and 22.5% for Bangladesh, India, and Nepal, respectively. For all age groups, men were more likely to be hypertensive than women in India and Nepal, but not in Bangladesh. Overweight and obesity were associated with higher odds of hypertension in all countries. For each 5 kg/m 2 increase in BMI, the ORs for hypertension were 1.79 (95% CI: 1.65-1.93), 1.59 (95% CI: 1.58-1.61), and 2.03 (95% CI: 1.90-2.16) in Bangladesh, India, and Nepal, respectively. The associations between BMI and hypertension were consistent across various subgroups defined by sex, age, urbanicity, educational attainment and household’s wealth index. Our study shows that the association of BMI with hypertension is stronger for South Asian populations, and public health measures to reduce population-level reduction in BMI would also help in lowering the burden of hypertension.