Monocyte/lymphocyte ratio is related to the severity of coronary artery disease and clinical outcome in patients with non-ST-elevation myocardial infarction

Monocyte/lymphocyte ratio (MLR), a widely used inflammation maker for prognosis of cancer, tuberculosis, and autoimmune diseases, has attracted more and more attention for its application to cardiovascular disease. The aim of the present study was to investigate the relationship of MLR with the severity of coronary lesion and clinical outcomes in non-ST-elevation myocardial infarction (NSTEMI) patients. 963 consecutive NSTEMI patients (mean age, 60.77 ± 11.34; 758 male) undergoing coronary angiography were analyzed and followed in 3 groups according to the average MLR tertile (low MLR <0.23, n = 321; intermediate MLR 0.23–0.35, n = 322; high MLR >0.35, n = 320) in this study. The severity of coronary lesion was determined by Gensini score. Multiple linear regression analysis was used to examine the correlation between MLR and the severity of coronary lesion. Kaplan–Meier curve was performed to compare the long-term major adverse cardiac event (MACE)-free survival. Logistic regression analysis and Cox proportional hazard regression model were used to assess the independent predictors for in-hospital and long-term MACE. MLR (B: 0.281, 95% confidence interval [CI]: 0.130–0.432, P < .001) and high-sensitivity C-reactive protein (B: 0.017, 95% CI: 0.010–0.024, P < .001) were both independently correlated with the severity of coronary lesion, while neutrophil/lymphocyte ratio was not. The frequencies of in-hospital MACE (1.6%, 2.2%, 4.7%, P = .016) and long-term MACE (13.3%, 16.2%, 27.2%, P < .001) both increased among the 3 groups. Kaplan–Meier curve analysis indicated that patients in high MLR group had worse long-term MACE-free survival than the patients in low MLR group (P(2) < .001) and intermediate MLR group (P(3) = .004) during a median follow-up of 22 (12–35) months. MLR was an independent predictor for in-hospital MACE (adjusted odds ratio: 2.891, 95% CI: 1.265–8.354, P = .026) and long-term MACE (adjusted hazard ratio: 1.793, 95% CI: 1.169–2.515, P = .012) in NSTEMI patients. MLR is independently correlated with the severity of coronary lesion and has better performance to reflect the severity of coronary lesion than NLR. MLR is an independent predictor for the MACE in NSTEMI patients.