Assessment of Future Hypertension Risk by Sex Using Combined Body Mass Index and Waist-to-Height Ratio

Background: Body mass index (BMI) and the waist-to-height ratio (WHtR) are widely used anthropometric indices of obesity to predict cardiovascular risks. However, the usefulness of combining WHtR and BMI values to predict hypertension risk by sex has not been well elucidated. Methods and Results: This cohort study enrolled 45,921 participants (mean [±SD] age 53.8±10.5 years; 47.0% men) without hypertension from among those undergoing annual health checkups. Participants were divided into 4 categories based on median BMI and WHtR values, and the 5-year incidence of hypertension was assessed for both sexes using logistic regression analysis. Mean (±SD) BMI and WHtR values were 23.5±3.1 kg/m(2) and 0.50±0.05, respectively, in men and 22.4±3.3 kg/m(2) and 0.53±0.06, respectively, in women. Among the women, those with high BMI and low WHtR had an increased risk of hypertension compared with those with low BMI and low WHtR (odds ratio [OR] 1.37, P<0.001); however, the same result was not found in men (OR 1.14, P=0.080). In both sexes, the incidence of hypertension was higher among participants with low BMI and high WHtR than among those with low BMI and low WHtR (men: OR 1.26, P<0.001; women: OR 1.15, P=0.048). Conclusions: Using WHtR and BMI together provides a better hypertension risk assessment. Among men, those with a high BMI had no increased hypertension risk when WHtR was low.