Prognostic value of cystatin C in relation to other markers of renal function in early prediction of hospital mortality and major cardiac adverse events in patients with ST elevation myocardial infarction treated by primary percutaneous coronary intervention

Abstract

IntroductionCystatin C has been implicated as a prognostic marker in cardiovascular diseases. The aim of prospective study was to evaluate the benefits of measuring cystatin C for prognostic stratification to predict hospital mortality and the rates of major cardiac adverse events (MACE) in ST elevation myocardial infarction (STEMI) patients and to compare cystatin C to other markers of renal function and Global Registry of Acute Coronary Events (GRACE) score. MethodsA total of 659 consecutive patients (479 men, mean age 65 years) from a prospective study on acute STEMI treated by primary percutaneous coronary intervention (PCI) were evaluated. Standard laboratory tests including cystatin C, troponin T, NT-terminal fragment of brain natriuretic peptide (NT-proBNP), markers of renal function were assessed on admission in all patients. Using c-statistic, the ability of cystatin C, other biomarkers and GRACE score to predict hospital mortality and MACE (acute coronary syndrome recurrence, stroke event, definite in-stent thrombosis and mortality) rate was evaluated. ResultsAll-cause hospital mortality and MACE occurrence were 4% (n=26) resp. 6.8% (n=45). Cystatin C, creatinine, urea, glomerular filtration rate, troponin T, NT-proBNP and GRACE on admission were identified as significant prognostic risk markers.Serum cystatin C level and GRACE score were significantly higher in non-survivors (1.65±0.91 vs. 0.97±0.41mg/mL; P<0.001 resp. 138±43 vs. 99±31; P<0.001). The area under the curve (AUC) values for mortality and MACE rate prediction for cystatin C and GRACE score were 0.83 and 0.88, respectively 0.66 and 0.72 (all P<0.001) with optimal cut-off values of 1.3mg/mL for cystatin C and 136 for GRACE score.Cystatin C above cut-off >1.30mg/L was associated with the highest adjusted odds ratio (OR) 3.85 (95% confidence interval 2.36–6.38; P<0.001), and predicted in-hospital mortality with 77% sensitivity and 86% specificity. The addition of cystatin C to the GRACE score (OR 1.05, 95% confidence interval 1.04–1.07; P<0.001) was not significantly associated with improved risk stratification. ConclusionsCystatin C is a predictor of early outcome comparable with the GRACE score in patients with STEMI.