Serum cystatin C levels are associated with coronary artery disease and its severity

Objectives: Serum cystatin C has been established as a predictor of cardiovascular events. The aim of this study was to evaluate the role of cystatin C in determining the presence and the severity of patients with coronary artery disease (CAD). Design and methods: A total of 936 subjects without overt renal disease were included in this cross-sectional study. Among them were 714 patients with CAD and 222 without based on coronary angiography. Subjects were further divided into four groups according to cystatin C quartile. Serum cystatin C was measured using particle-enhanced immunoassay method. The study analyzed the relationship of cystatin C levels with the presence and severity of CAD, including the number of stenotic vessels involved and Gensini score. Results: Serum cystatin C levels were significantly higher in patients with CAD than those without (P < 0.001), and significantly increased as the involvement of coronary vessels increased (P < 0.001). The prevalence of CAD and its severity assessed by Gensini score were also significantly greater in the highest quartile of cystatin C (P < 0.001). Moreover, cystatin C levels were independently correlated with the presence of CAD in a multivariate logistic regression model (P = 0.023) and were positively correlated with Gensini score by linear regression analysis (standardized beta = 0.083, P = 0.010). Conclusions: Elevated serum cystatin C levels were significantly associated with the presence and severity of CAD in patients with normal renal function. It is suggested that cystatin C might play a role in CAD diagnosis and serve as a marker of CAD severity. (C) 2014 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.