Cystatin C, Associated With Hemorrhagic and Ischemic Stroke, Is a Strong Predictor of the Risk of Cardiovascular Events and Death in Chinese

BACKGROUND AND PURPOSE: Cystatin C, a serum measure of renal function, has been reported as a strong predictor of risk of death and cardiovascular events in elderly people. We investigated the association between cystatin C and first-ever stroke and evaluated the predictive value of cystatin C in cardiovascular events and death from all causes based on the outcomes of a 5-year follow-up. METHODS: We recruited 293 stroke patients (199 cases of cerebral infarction, 94 cases of cerebral hemorrhage) and 894 controls. For each measure, the study population was divided into quintiles. RESULTS: Total plasma cystatin C levels were significantly higher in patients than controls. Higher cystatin C levels were directly associated with a higher risk of stroke. As compared with the first (lowest) quintile, the hazard ratios (and 95% CIs) for stroke were as follows: second quintile, 1.97 (1.07 to 3.64); third quintile, 2.71 (1.50 to 4.90); fourth quintile, 3.79 (2.12 to 6.75); fifth quintile, 6.38 (3.60 to 11.32). Follow-up of the patients and controls also showed that high cystatin C levels were associated with high prevalence of cardiovascular events or death from all causes. CONCLUSIONS: Elevated cystatin C levels were independently associated with both ischemic and hemorrhagic stroke, and cystatin C was a strong predictor for the risk of cardiovascular events and death.