Abstract P390: Relationship between BMI and Risk of Hypertension in an urban Japanese cohort study: the Suita study
Objective: The positive relation between body mass index (BMI) and risk of incident hypertension (HT) has been reported mainly in the Western subjects with high BMI. However, there are a few reports in the Asian with relatively lower BMI. This study investigated the relation of BMI with risk of incident HT in the population-based prospective cohort study of Japan, the Suita study. Methods: Participants who had no HT at baseline (1,591 men and 1,973 women) aged 30-84 years were included in this study. BMI categories were defined as following: underweight (BMI<18.5), normal (18.5≤BMI<25.0), and overweight (BMI ≥ 25.0). The Cox proportional hazards model was used to estimate hazard ratios (HRs) of BMI categories for incident HT by sex. HRs were adjusted for age, cigarette smoking and alcohol drinking. The HRs according to quartiles of BMI were also estimated, using the lowest quartile of BMI as a reference. Results: During median follow-up of 7.2 years, 1,325 participants (640 men and 685 women) developed HT. The HR (95% CI) of 1kg/m2 increment of BMI for HT in men and women was 1.08 (1.05-1.11) and 1.10 (1.07-1.12), respectively. When we set a normal BMI as a reference, HR of overweight BMI in men and women was 1.37 (1.13-1.67) and 1.45 (1.18-1.77), whereas HR of underweight BMI in men and women was 0.63 (0.45-0.90) and 0.60 (0.45-0.80), respectively. In addition, compared to the lowest quartile, HR of the highest quartile of BMI in men and women was 1.67 (1.33-2.10, trend p<0.001) and 2.10 (1.67-2.64, trend p<0.001), respectively. Conclusion: In this study, we showed that higher BMI was associated with increased risk of hypertension in both Japanese men and women.