High-density lipoprotein cholesterol and risk of stroke in Japanese men and women: the Oyabe Study.

Background And Purpose: Evidence of an inverse relationship between serum high-density lipoprotein cholesterol (HDL-C) and the risk of stroke is sparse in Asians and in women. The purpose of this investigation was to examine the relationship in a long-term cohort study of Japanese men and women among whom stroke occurrence is higher than in Western countries.

Methods: A prospective cohort study was performed involving 4989 participants (1523 men, 3466 women) 35 to 79 years of age at baseline with approximately 10 years of follow-up in a rural area of Japan. End points included all stroke incidence and ischemic stroke incidence.

Results: During follow-up, 132 participants developed stroke, including 81 ischemic stroke cases. Age-adjusted incidence rates per 10,000 person-years for all stroke in subjects with low HDL-C (<30 mg/dL [0.78 mmol/L]) were 103.4 in men and 49.3 in women, which were remarkably higher than in subjects with high HDL-C (>or=60 mg/dL [1.56 mmol/L]) (26.4 in men and 15.5 in women). A similar relationship was observed for ischemic stroke. Multivariate-adjusted relative risks for all stroke incidence and ischemic stroke incidence were 2.89 (95% CI, 1.35 to 6.20) and 2.92 (95% CI, 1.17 to 7.32), respectively, for low versus high HDL-C participants. The relationships were independent of sex, age, body mass index, blood pressure, serum total cholesterol, alcohol consumption, and smoking.

Conclusions: This 10-year follow-up study of Japanese men and women demonstrated that lower HDL-C levels were related significantly and independently to increased risk of all stroke incidence and ischemic stroke incidence.