Anthropometric indices predicting incident hypertension in an Iranian population: The Isfahan cohort study

Abstract

Objective: The aim of the present study was to assess different obesity indices, as well as their best cut-off point, to predict the occurrence of hypertension (HTN) in an Iranian population. Methods: In a population-based study, subjects aged 35 years and older were followed for 7 years. Blood pressure was measured at baseline and after the follow-up. Anthropometry indices included body mass index (BMI), body adiposity index (BAI), the waist-to-height ratio (WHtR), the waist-to-hip ratio (WHpR), and waist and hip circumferences (WC and HC). Logistic regression was employed to calculate the odds ratio (OR) and 95 confidence intervals (CI) per standard deviation (SD) increment. The operating characteristic analysis was used to derive the best cut-off value for each index. Results: Among original 6504 participants, 2450 subjects who had no cardiovascular diseases (CVD) and HTN at baseline were revisited, and 542 (22.1) new cases of HTN were detected. There were minimal differences between most indices in the adjusted models; however, the best HTN predictors were BMI (OR per SD 1.32; 95 CI 1.12-1.56) and almost equally WC (1.35; 1.13-1.60) in men and WC (1.20; 1.04-1.39) in women. As a binary predictor, BMI with a cut-off point of 24.9 kg/m(2 ) in men (1.91; 1.40-2.62) and WC with a cut-off point of 98 cm in women (1.57; 1.17-2.10) were the best in adjusted models. WC, WHpR, and WHtR were significantly associated with an increased risk of HTN only in participants whose weight was normal (BMI, 18.5-24.9 kg/m(2)). Conclusion: Therefore, BMI in men and WC in women were the best predictors of HTN, both as continuous and binary factors at their appropriate cut-off points.