Combined Use of Neutrophil to Lymphocyte Ratio and C-Reactive Protein Level to Predict Clinical Outcomes in Acute Myocardial Infarction Patients Undergoing Percutaneous Coronary Intervention

BACKGROUND AND OBJECTIVES Both neutrophil to lymphocyte ratio (NLR) and C-reactive protein (CRP) are biomarkers associated with poor prognosis of patients with acute myocardial infarction (AMI). However, the combined usefulness of NLR and CRP in predicting adverse outcomes has not been investigated. SUBJECTS AND METHODS We analyzed 381 consecutive AMI patients who underwent percutaneous coronary intervention (PCI) from January 2012 to January 2014. The endpoints were all-cause mortality, recurrent myocardial infarction (MI), stent thrombosis, repeat revascularization, stroke, and major adverse cardiac and cerebrovascular events (MACCE) at 2-year follow-up. Included patients were divided into 4 groups according to the optimal cut-off values for NLR and CRP on receiver operating characteristic analysis predicting mortality. RESULTS Patients with both high NLR (>6.30) and high CRP (>0.76) had significantly greater risk of all-cause death and MACCE at 24 months, with no significant increase in the risk of recurrent MI, stent thrombosis, or stroke compared with patients with either low NLR or low CRP, as well as those with low NLR and low CRP. Kaplan-Meier analysis revealed significantly lower survival in patients with high NLR-CRP. On Cox multivariate analysis, high NLR-CRP (hazard ratio 23.172, 95% confidence interval 6.575 to 81.671, p<0.001) was an independent predictor of all-cause death. CONCLUSION Elevated levels of both NLR and CRP are associated with increased risk of long-term mortality in AMI patients who have undergone PCI.