Association between body mass index (BMI) and hypertension in south Asian population: evidence from nationally-representative surveys

摘要

IntroductionHypertension is one of the important preventable noncommunicable disease (NCD) risk factors for premature death and disability [1,2,3]. About one-third of world’s adult population are hypertensive - according to recent reports [4, 5]. The burden of hypertension is increasing particularly in the low- and middle-income countries (LMICs) [5]. South Asia comprises of several LMICs and almost one-quarter of the world’s population lives in South Asia. Therefore, a greater understanding of the burden of hypertension in this region is required to develop public health interventions to control it.There has been a well-established association between adiposity and hypertension in developed settings [6,7,8], but whether such association is heterogeneous for South Asian population is not well-known. Several previous studies have suggested that South Asian adults have substantially lower cut-off points for overweight and obesity than White Europeans, which are associated with higher risks of type 2 diabetes and cardiovascular disease [9, 10]. However, the associations between overweight and obesity at South Asian cut-offs with hypertension have not been explored adequately in the current literature - lacks statistical power, national representation, or adjustments for covariates.Assessing association between body mass index (BMI) and hypertension has important public health implications in South Asian countries, where the burden of hypertension is high and obesity is increasing at the population level [11,12,13]. In addition, looking at the association in subgroups defined by sex, age, urbanicity, and socioeconomic status is crucial to understand how consistent the association between BMI and hypertension is across different groups. There is no study, to the best of our knowledge, which looked at the association of BMI with hypertension across different groups in nationally-representative samples from South Asian countries.In this study, we aim to examine the age-specific prevalence of hypertension in three South Asian countries, namely Bangladesh, India, and Nepal. We also systematically assess the association between overweight-obesity and hypertension using different cut-offs, and how the association between BMI and hypertension varies across a wide variety of subgroups of population.