Accuracy of neutrophil to lymphocyte and monocyte to lymphocyte ratios as new inflammatory markers in acute coronary syndrome

BACKGROUND: Inflammation plays a key role in the development of atherosclerosis and in the pathogenesis of acute coronary syndrome (ACS). Leukocytes and leukocytes ratios were recognized as inflammatory markers in predicting the presence and severity of ACS. METHODS: This study aimed to investigate the diagnostic accuracy of neutrophil to lymphocyte ratio (NLR) and monocyte to lymphocyte ratio (MLR) with ACS. One hundred patients admitted to the Cardiac Center who were confirmed to have ACS and 100 healthy controls confirmed not to have ACS were enrolled in this study. ECG and troponin I test were used as gold standards to make sure that the participants with or without ACS. Total white blood cells (WBCs) count, NLR, and MLR values were estimated. RESULTS: Total WBCs, neutrophil, and monocyte counts were significantly higher while lymphocyte counts were significantly lower in ACS patients than in the healthy controls (p < 0.001). NLR and MLR were significantly higher in ACS patients than in the healthy controls (p < 0.001). Among all the studied markers, NLR was found to be the strongest predictive marker of ACS (OR: 3.3, p < 0.001), whereas MLR was non-significant (p > 0.05). A cut-off value of 2.9 of NLR had 90% sensitivity and 88% specificity while 0.375 cut-off value of MLR had 79% sensitivity, 91% specificity for predicting ACS presence. CONCLUSIONS: NLR is a simple, widely available, and inexpensive inflammatory marker which can be an auxiliary biomarker in the diagnosis of ACS with a cut-off value of 2.9 in our population.