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.