[Which cut-off value of high sensitivity C- reactive protein is more valuable for determining long- term prognosis in patients with acute coronary syndrome?].

Objective: The aim of this study to investigate prognostic efficacy of high sensitivity C-reactive protein (hs-CRP) in patients with acute coronary syndrome (ACS) and to identify the most valuable cut-off value of hs-CRP for determining long term prognosis.
Methods: A total of 240 ACS patients presenting within 6 h after the onset of chest pain were included to the study. Admission levels of hs-CRP were analyzed. Patients were followed for 1 year. Primary end-point of the study was new coronary event (NCE), defined as the combination of cardiac death, nonfatal myocardial infarction and recurrent rest angina. Risk factors for NCE were determined by logistic regression analysis. ROC-curve analysis was used to identify cut-off values of the risk factors. The prognostic efficacy of the cut-off value of hs-CRP was compared to other values determined from other studies. Kaplan Meier and log rank tests were used in survival analyses. Factors determining event-free survival were investigated by Cox regression analysis.
Results: During the follow-up period, 65 NCEs occurred. In multivariate analysis, hs-CRP was strongly associated with the occurrence of NCE (OR=4.79, 95% CI=2.10-10.44, p<0.001). Cut-off value of hs-CRP for NCE was 1.1 mg/dl (AUC=0.68, 95% CI=0.62-0.74, p<0.001). Compared to other values of different studies, hs-CRP>1.1 mg/dl had the optimal positive and negative predictive values. In the Cox regression analysis, hs-CRP was emerged as the most important parameter for determining event-free survival (RR=3.44, 95% CI=1.91-6.21, p<0.001).
Conclusion: Admission levels of hs-CRP were emerged as the most important parameter for prognosis and the cut-off value of hs-CRP for predicting NCE was found as 1.1 mg/dl in this cohort of the study population. Further studies are required to confirm the most risky cut off value of hs-CRP for predicting long term prognosis among ACS patients and in general population.