Effect of lymphocyte-to-monocyte ratio on survival in septic patients: an observational cohort study

Abstract

Introduction: The purpose of the present study was to evaluate the potential relationship of lymphocyte-to-monocyte ratio (LMR) with outcomes of septic patients at intensive care unit (ICU) admission. Material and methods: 3087 septic patients were included in the final cohort by using the Medical Information Mart for Intensive Care (MIMIC) database. We evaluated the association of different groups of LMRmax with 28-day survival and 1-year survival via Kaplan-Meier (K-M) analysis and Cox regression analysis. Subgroups analysis of LMRmax was performed to further explore the effect of LMRmax on survival. Results: According to the optimal cut-off value, the cohort was divided into low-LMRmax and high-LMRmax groups. The 28-day and 1-year survival rates were 47.9% and 19.9%, respectively, in the low-LMRmax group, and 60.4% and 25.9%, respectively, in the high-LMRmax group. Univariate logistic regression and K-M analyses revealed that the 28-day and 1-year survival rates of the high-LMRmax group were higher than those of the low-LMRmax group (both p < 0.001). A subgroup analysis of LMRmax identified a significant stepwise decrease in the risk of death at 28 days and 1 year from group 1 to group 4 (LMRmax increased gradually) after adjustment for multiple variables. Conclusions: We report for the first time that a lower LMRmax value is independently predictive of a poor prognosis in septic patients. Therefore, as an inexpensive and readily available indicator, LMRmax may facilitate stratification of prognosis in septic patients.