Comparison of the long-term prognostic value of Cystatin C to other indicators of renal function, markers of inflammation and systolic dysfunction among patients with acute coronary syndrome

Objective: Emerging evidence indicates the prognostic importance of Cystatin C (Cys-C) in patients with coronary artery disease. However, whether Cys-C concentrations are associated with adverse clinical events among patients with acute coronary syndromes (ACS) have not been studied extensively. We compared the long-term prognostic efficacy of Cys-C with other markers of renal dysfunction, inflammation and systolic dysfunction in patients with ACS. Methods and results: Serum levels of Cys-C, high sensitive C-reactive protein (hs-CRP), brain natriuretic peptide (BNP) and creatinine were measured in 160 patients with ACS (112 males, 48 females, mean age 60 +/- 10 years) on admission. Primary end point of the study was major adverse cardiac events (MACE) defined as the combination of cardiac death, non-fatal myocardial infarction and recurrent rest angina that required hospitalization within 12 months of follow-up. During the follow-up period, 42 (26%) patients met the MACE criteria. The occurrence of MACE was significantly higher among patients with higher Cys-C levels. In multivariate analysis, Cys-C was the most important parameter associated with the occurrence of MACE (OR = 9.62, 95% CI = 2.3-40.5, p < 0.001). ROC curve analysis showed that the predictive cut-off value of Cys-C for MACE was 1051 ng/ml. In the Cox regression analysis adjusted for multiple risk factors, Cys-C was found as the most powerful predictor for MACE (RR = 9.43, 95% CI = 4.0-21.8, p < 0.001). Conclusion: The results of the present study indicate that admission levels of Cys-C may be a good prognostic indicator of recurrent cardiovascular events in patients with ACS. Further studies are needed to confirm these results. (C) 2009 Elsevier Ireland Ltd. All rights reserved.