title: Cystatin C and asymptomatic coronary artery disease in patients with metabolic syndrome and normal glomerular filtration rate.
abstract: BACKGROUND
  All of the components of metabolic syndrome (MetS) have been regarded as risk factors for coronary artery disease (CAD). Early detection of CAD in asymptomatic patients with MetS remains a challenge. Cystatin C,which has been proposed as a novel marker of renal dysfunction,is correlated with mortality in CAD, The purpose of the study was to evaluate whether cystatin C is a potential marker of asymptomatic CAD in MetS patients with normal kidney function.
  
  
  METHODS
  A total of 211asymptomatic MetS patients without prior history of CAD patients were included in a cross-sectional study. Patients were divided into MetS with asymptomatic CAD (n=136) and MetS without CAD (n=75) groups according to coronary angiograph results. Serum cystatin C levels were measured using particle enhanced immunonephelometric assays. We first assessed whether there is an independent association of cystatin C with the presence and severity of asymptomatic CAD. Then, we investigated the association between cystatin C and other biochemical risk factors for atherosclerosis.
  
  
  RESULTS
  Serum cystatin C levels in patients with asymptomatic CAD were significantly higher than those without CAD (P=0.004). A multiple logistic regression analysis demonstrated cystatin C was independently associated with the presence of asymptomatic CAD (OR=1.326, 95%CI: 1.086-1.619). On receiver operating characteristics (ROC) analysis, the area under the curve (AUC) was 0.622 (95% CI: 0543-0.701, P=0.003), and cystatin C showed a moderate predictive value. Furthermore, cystatin C was independently correlated with Gensini score (standardized β=0.183, P=0.007), and serum cystatin C levels increased with the increasing of number of disease vessels (P=0.005). In a multiple stepwise regression analysis, uric acid (UA)(P<0.001), body mass index (BMI)(P=0.002), triglyceride(TG)(P=0.03), estimated glomerular filtration rate (eGFR)(P<0.001), and fibrinogen(P=0.001) were independently associated with cystatin C.
  
  
  CONCLUSIONS
  Serum cystatin C in our study was significantly associated with the presence and severity of asymptomatic CAD in MetS patients with normal kidney function, suggesting that cystatin C is probably more than a marker of glomerular filtration rate.
authors.affiliation: Department of Central Laboratory, Provincial Hospital affiliated to Shandong University, Jinan, People's Republic of China.
authors.forename: Xie
authors.initials: X
authors.lastname: Qing
authors.forename: Wang
authors.initials: W
authors.lastname: Furong
authors.forename: Liu
authors.initials: L
authors.lastname: Yunxia
authors.forename: Zhang
authors.initials: Z
authors.lastname: Jian
authors.forename: Wang
authors.initials: W
authors.lastname: Xuping
authors.forename: Gao
authors.initials: G
authors.lastname: Ling
mesh_terms: D000368:Aged; D019540:Area Under Curve; D058070:Asymptomatic Diseases; D015415:Biomarkers / Q000097:blood; D016009:Chi-Square Distribution; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000097:blood* / Q000175:diagnosis; D003430:Cross-Sectional Studies; D055316:Cystatin C / Q000097:blood*; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D016015:Logistic Models; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood* / Q000175:diagnosis / Q000503:physiopathology; D008875:Middle Aged; D015999:Multivariate Analysis; D009391:Nephelometry and Turbidimetry; D016017:Odds Ratio; D011237:Predictive Value of Tests; D012372:ROC Curve; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D015854:Up-Regulation
chemical_list: D015415:Biomarkers; C525030:CST3 protein, human; D055316:Cystatin C