Abstract:

Objective　To study the relationship of cystatin C (Cys C) concentration with short term prognosis in acute coronary syndrome (ACS) patients. Methods　A total of 386 ACS patients were enrolled, including 212 patients with ST elevation ACS (STE-ACS) and 174 patients with non-ST elevation ACS (NSTE-ACS). Serum B-type natriuretic peptide (BNP), high sensitive C reactive protein (hs-CRP), Cys C and cardiac troponin I (cTnI) were determined within 24h after admission. Serum Cys C was classified according to percentile intervals. Rank-sum test was used to compare the levels of BNP, hs-CRP,age and weight in the different groups and the differences of Cys C concentrations in the STE-ACS and NSTE-ACS groups. χ² test was used to compare the distribution differences of hypertension,diabetes mellitus, high cholesterol and smoking in the different groups. The cardiovascular events of the selected patients during hospitalization and after discharge were followed up. The cumulative incidence rates of cardiovascular events were compared among the different groups, Kaplan-Meier curves of cumulative incidence rates of cardiovascular events to time were drawn, and receiver operating characteristic (ROC) curve was drawn to assess Cys C predictive adverse outcome in patients with ACS. Results　According to Cys C concentration percentile intervals, the ACS patients were classified into <0.69 mg/L group (96 patients), 0.69-<0.86 mg/L group (97 patients), 0.86-<1.03 mg/L group (98 patients) and ≥1.03 mg/L group (95 patients). The age,BNP and hs-CRP also increased in the different groups,as well as the distributions of hypertension,diabetes mellitus and high cholesterol. Weight and smoking distributions in each group had no significant difference. Cys C concentration in STE-ACS group had no statistical significance with that in NSTE-ACS (P>0.05). The cumulative incidence rates of cardiovascular events in the different groups were 6.3%, 7.2%, 9.2% and 18.9% from low-concentration Cys C to high-concentration Cys Crespectively, but there was statistical significance between ≥1.03 mg/L group and <0.69 mg/L group, according to Kaplan-Meier curves (P<0.05). The area under ROC curve predicting the risk of adverse outcome was 0.754. Conclusions　Cys C concentration is positively correlated with BNP, hs-CRP, age, hypertension, diabetes mellitus and high cholesterol, and it contributes particularly in predicting the adverse outcome in patients with ACS, with no interaction by the type of ACS.

Key words: Cystatin C, B-type natriuretic peptide, High sensitive C reactive protein, Acute coronary syndrome