Prevalence and magnitude of classical risk factors for stroke in a cohort of 5092 Chinese steelworkers over 13.5 years of follow-up.

BACKGROUND AND PURPOSE

Stroke is the most common manifestation of cardiovascular disease (CVD) among Chinese men. This study addresses the prevalence and magnitude of classic CVD risk factors associated with total, ischemic, and hemorrhagic stroke in a Chinese cohort of at-risk men, compared with white populations. We also address which blood pressure index: systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and pulse pressure (PP) is the best predictor of stroke.

METHODS

A cohort of 5092 male steelworkers (aged 18 to 74 years) recruited between 1974 to 1980 was followed up for an average of 13.5 years. The results showed that the risk ratios (RRs) of stroke associated with classic risk factors in this Asian population were not different than in whites, except for blood pressure. The RRs of total stroke for each 10mm Hg rise in SBP and DBP in this Asian group (1.4 and 1.8, respectively) were higher than in whites (1.2 to 1.3 and 1.2 to 1.5, respectively). The population attributable risk (PAR) for hypertension (160/95 mm Hg cutoff) to stroke was higher in Asians (ie, 31% for ischemic and 42% for hemorrhagic stroke) than in whites (25% and 34%, respectively).

CONCLUSIONS

Our results indicate that hypertension is a greater risk factor for stroke in Asians than whites, especially for hemorrhagic stroke. The most predictive blood pressure (BP) index for stroke is MAP. However, the prevalence or magnitude of these traditional risk factors appears unlikely to explain the differing spectrum of CVD among Asians.