Ankle-brachial blood pressure in elderly men and the risk of stroke: the Honolulu Heart Program

Ankle-arm blood pressure index and cardiovascular risk factors in elderly Japanese men

Low ankle-arm systolic blood pressure index (AAI) correlates with various cardiovascular risk factors and with risk of subsequent coronary heart disease and stroke in Western countries. However, few epidemiological data are available among Japanese, in whom the reported prevalence of peripheral artery disease is low. We examined the relationship between AAI and cardiovascular risk factors among 1,219 men aged 60 to 79 years in two Japanese communities in 1999 and 2000. The prevalence of AAI<0.90 was 5% in both communities. Hypertension, major ECG abnormality, current smoking, and history of stroke were associated with two- to four-fold higher prevalence of AAI<0.90. One-standard deviation increments of body mass index and high density lipoprotein-cholesterol levels were associated with 60% and 40% lower prevalence of AAI<0.90, respectively. Although the prevalence of low AAI in Japanese elderly men is lower than that reported in the Unites States and European studies, similar correlations of low AAI with cardiovascular risk factors were observed among different ethnic groups. Low AAI is suggested to be a predictor for stroke among Japanese men, which should be confirmed by a prospective study.

Age-related changes in risk factor effects on the incidence of thromboembolic and hemorrhagic stroke

We examined the changes in risk factor effects on the incidence of thromboembolic and hemorrhagic stroke as they may occur with age. Findings were based on repeated risk factor measurements at four examinations over a 26-year period in 7589 men in the Honolulu Heart Program. After each examination, 6 years of follow-up were available to assess risk factor effects on the incidence of stroke over a broad range of ages (45-93 years). As compared with normotensive men, the risk of thromboembolic stroke in the presence of hypertension declined from a 7-fold excess in men aged 45 to 54 years to a 1.4-fold excess in men aged > or =75 (P<.001). Adverse effects of diabetes and atrial fibrillation seemed to be equally important across all ages, whereas a protective effect of physical activity increased with age. Except for men with atrial fibrillation, the incidence of thromboembolic stroke increased significantly with age regardless of risk factor status, including men with normal blood pressure (P<.001). Although hemorrhagic events were less common, positive relations with cigarette smoking seemed to strengthen with age, whereas those with hypertension tended to decline. Our findings suggest that strategies for the prevention of stroke may need to account for changes in risk factor effects as they occur with age. Control of diabetes and the encouragement of active lifestyles in the elderly seem to be especially important.