Risk factors and the incidence of coronary artery disease in young middle-aged Japanese men: Results from a 10-year cohort study

Objective: The objective of this study was to elucidate the relationship between risk factors and the coronary artery disease (CAD) in young middle-aged Japanese men. Methods: A cohort study of 2,764 young middle -aged Japanese men aged 35-44 (mean±SD: 42.3±2.5) years based on a 10-year follow-up to identify the risk factors for the occurrence of CAD was conducted. There were 35 cases of CAD during the follow up; 25 myocardial infarctions and 10 angina pectoris. The Cox Proportional hazard model was used to identify the independent risk factors for CAD. Adjustment was made for variables including age, body mass index, smoking habit, systolic blood pressure, total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), fasting plasma glucose (FPG), and triglyceride. Results: TC, l ow HDL-C, and FPG were identified as significant independent risk factors for CAD. Adjusted hazard ratio (HR) of a high level of TC≥220 (mg/dl) for CAD was 5.46 (95% confidence interval (CI): 1.96-17.51) and that of a high level of HDL-C<50(mg/dl) was 9.01 (95%CI: 1.13-72.17), and a high level of FPG≥110 (mg/dl) was 2.94 (95%CI: 1.22-8.23). Considering the combination of these risk factors, adjusted HR for CAD of the subjects who had 2 risk factors was 8.37 (95%CI: 2.21-31.65). Conclusions: Using the database of young middle-aged Japan esemen, TC, low HDL-C, and FPG were found to be important risk factors for CAD, and the combination of these risk factors was associated with CAD.