Body Mass Index and Mortality from Nonrheumatic Aortic Valve Disease among Japanese Men and Women

Aim: We aimed to examine the impact of overweight and obesity on mortality from nonrheumatic aortic valve disease.Methods: In the Japan Collaborative Cohort Study, we analyzed data of 98,378 participants aged 40-79 years, with no history of coronary heart disease, stroke, or cancer at baseline (1988-1990) and who completed a lifestyle questionnaire including height and body weight; they were followed for mortality until the end of 2009. The Cox proportional hazards model was used to calculate the multivariable hazard ratios (HRs) with 95% confidence intervals (CIs) of nonrheumatic aortic valve disease mortality according to body mass index (BMI) after adjusting for potential confounding factors.Results: During the median 19.2 years follow-up, 60 deaths from nonrheumatic aortic valve disease were reported. BMI was positively associated with the risk of mortality from nonrheumatic aortic valve disease; the multivariable HRs (95% CIs) were 0.90 (0.40-2.06) for persons with BMI <21 kg/m2, 1.71 (0.81-3.58) for BMI 23-24.9 kg/m2, 1.65 (0.69-3.94) for BMI 25-26.9 kg/m2, and 2.83 (1.20-6.65) for BMI >= 27 kg/m2 (p for trend=0.006), compared with persons with BMI 21-22.9 kg/m2. Similar associations were observed between men and women (p for interaction=0.56). Excluding those who died during the first ten years of follow-up or a competing risk analysis with other causes of death as competing risk events did not change the association materially.Conclusions: Overweight and obesity may be independent risk factors for nonrheumatic aortic valve disease mortality in Asian populations.