Body mass index, abdominal fatness, and hypertension incidence: a dose-response meta-analysis of prospective studies.

Despite the established relationship of obesity to hypertension, the question as to whether there is a linear association between these two morbidities is unanswered. To quantitatively evaluate the relationship between obesity and hypertension, we carried out a dose-response meta-analysis of studies that looked at the relationship of different adiposity measures to hypertension. We searched PubMed, Embase, and Web of Science databases for articles published before 27 June 2017. A random-effects model was used to pool relative risks and 95% confidence intervals. Restricted cubic spline analysis was used to model the relationship. A total of 59 studies were included. Fifty-seven cohort studies with 125,071 incident cases among 830,685 participants were included in the analysis of body mass index and hypertension with the summary relative risk for per 5-unit increment in body mass index of 1.50 (95% confidence interval: 1.40-1.59). We found that the risk of hypertension in the body mass index analysis was greater in populations where the baseline body mass index was <25 kg/m. The summary relative risk for a 10-cm increase in waist circumference was 1.25 (95% confidence interval: 1.19-1.32) and per 0.1-unit increase in waist-to-hip ratio was 1.27 (95% confidence interval: 1.18-1.37). This meta-analysis suggests that in normal range of obesity indexes, as lean as possible may be the best suggestion to prevent hypertension incidence.