Study on mortality, incidence and risk factors of stroke in a cohort of elderly in Xi'an, China

OBJECTIVE: To prospectively study the relationship between risk factors and stroke incidence and mortality in the Chinese elderly. METHODS: An analytic study in a cohort population of 1,268 male retired cadres in a military setting. A health-screening program was carried out for all cadres aged 55 years or older in Xi'an in February 1987. Baseline data on smoking, cholesterol, triglyceride, blood pressure, body mass index (BMI), histories of hypertension, hyperlipidemia and coronary heart disease (CHD), stroke, diabetes and family histories of cardiovascular disease were investigated. Main outcome measures were stroke incidence, stroke and all-cause mortality. RESULTS: The cohort was followed up until June 30, 2001 and a total number of follow-up person-year was 15,546. During the follow-up period, there were 113 new stroke cases identified and the adjusted incidence was 727 per 100,000 person-year. Forty-five deaths were due to stroke and the adjusted mortality was 289 per 100,000 person-year. Using Cox model analysis, after adjustment on age, total cholesterol, triglyceride, smoking, drinking and physical exercise, we noticed that the systolic pressure, BMI, history of CHD and hyperlipidemia were independent risk factors for stroke incidence and morality. CONCLUSION: The incidence and mortality of stroke in this cohort were lower than those in the same age group of general population. Monitoring and controlling body mass index and blood pressure level seemed to be important factors for the prevention of stroke in the elderly.