Prognostic utility of the combination of monocyte-to-lymphocyte ratio and neutrophil-to-lymphocyte ratio in patients with NSTEMI after primary percutaneous coronary intervention: a retrospective cohort study

OBJECTIVES: This study aimed to evaluate prognostic value of the combination of monocyte-to-lymphocyte ratio (MLR) with neutrophil-to-lymphocyte ratio (NLR) for predicting long-term major adverse cardiac events (MACE) in patients with non-ST elevated myocardial infarction (NSTEMI) who underwent primary percutaneous coronary intervention (PCI). DESIGN: Retrospective cohort study. SETTING: Civil Aviation General Hospital, Beijing, China. PARTICIPANTS: 678 patients with NSTEMI undergoing primary PCI between July 2010 and July 2015 were enrolled. MAIN OUTCOME MEASURES: The main outcomes were MACE. The cumulative MACE-free survival rates were calculated by Kaplan-Meier analysis and the independent predictors of MACE were assessed by Cox regression analysis. RESULTS: According to the cut-off values of MLR 0.36 and NLR 2.15, the study population was classified into four groups: low MLR + low NLR group (n=319), low MLR + high NLR group (n=126), high MLR + low NLR group (n=102) and high MLR + high NLR group (n=131). The high MLR + high NLR group had a lower MACE-free survival rate than the other three groups (p logrank <0.001). Both MLR (HR 2.128, 95% CI 1.458 to 3.105) and NLR (HR 1.925, 95% CI 1.385 to 2.676) were independent predictors of long-term MACE. Moreover, the patients in the high MLR + high NLR group had an HR of 4.055 (95% CI 2.550 to 6.448) for long-term MACE, with the low-MLR + low NLR group as reference. Comparisons of receiver operating characteristic curves revealed that the combination of MLR with NLR achieved better performance in differentiating long-term MACE, compared with MLR, NLR, high-sensitivity C reactive protein and brain natriuretic peptide alone, and had similar performance to all other pairwise combinations of the four biomarkers. CONCLUSIONS: Elevated levels of MLR and NLR were independent predictors of long-term MACE in patients with NSTEMI. Moreover, the combination of MLR and NLR could improve the prognostic value in predicting long-term MACE.