Relation of Serum Total Cholesterol and Other Risk Factors to Risk of Coronary Events in Middle-Aged and Elderly Japanese Men With Hypercholesterolemia

BACKGROUND: The role of serum total cholesterol (TC) in the development of coronary heart disease (CHD) may differ in different age groups. METHODS AND RESULTS: The relation of serum TC and other risk factors to CHD events was examined in middle-aged (<65 years) and elderly (> or =65 years) men separately in the Kyushu Lipid Intervention Study (KLIS). Subjects were 4,349 men aged 45-74 years with serum TC of 220 mg/dl or greater who had no history of myocardial infarction, coronary angioplasty, or stroke. There were 123 CHD events (ie, myocardial infarction, coronary bypass surgery, coronary angioplasty, cardiac death, and sudden death) in a 5-year follow-up period. The Cox proportional hazards model was used with baseline and follow-up serum TC, baseline high-density lipoprotein (HDL) cholesterol, hypertension, diabetes mellitus, and other factors as covariates. Serum TC concentration during the follow-up, not at baseline, was associated with an increased risk of CHD events, especially in elderly men. High concentrations of serum HDL cholesterol were associated with a modest, statistically nonsignificant decrease in the risk among middle-aged men. An increased risk of CHD events associated with diabetes mellitus was greater in middle-aged men. Hypertension and smoking were not measurably related to the risk in either middle-aged or elderly men. CONCLUSIONS: Both the serum TC concentration during follow-up and diabetes mellitus are important predictors of CHD events in Japanese men with moderately elevated serum TC.