Neutrophil-to-lymphocyte ratio: A potential new peripheral biomarker of suicidal behavior.

Ángela Velasco,Sébastien Guillaume,Emilie Olié,Iciar Abad,Julia Rodríguez-Revuelta,Luis Jiménez-Treviño,Lorena De La Fuente-Tomás,Julio Bobes,Abel Fernández-Peláez,Paz García-Portilla,Philippe Courtet,Aurélie Cazals,Pilar A Sáiz,Laura Gutiérrez

doi:10.1192/j.eurpsy.2019.20

Abstract

Neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), and platelet-to-lymphocyte ratio (PLR) have emerged as important peripheral inflammatory biomarkers. Recent data suggest a possible role of the immune system in the pathophysiology of suicidal behavior (SB). The aim of this study is to evaluate the association among NLR, MLR, and PLR and SB in patients with major depressive disorder (MDD), and to test its validity as a biomarker for suicidality. We evaluated 538 patients with MDD (mean age [standard deviation]=43.87 [14.36] years; females: 68.8%). A logistic regression model was estimated to determine the independent factors associated with suicide risk in patients with and without a history of suicide attempt (SA). Three hundred ninety-three patients (74.7%) had a personal history of SA. Patients with a previous SA were more frequently female (71.9% vs. 59.6%; p=0.007), significantly younger (41.20 vs. 51.77years; p<0.001), had lower depression severity at enrolment (15.58 vs. 18.42; p<0.000), and significantly higher mean NLR and PLR ratios (2.27 vs. 1.68, p=0.001; 127.90 vs. 109.97, p=0.007, respectively). In the final logistic regression model, after controlling for age, sex, and depression severity, NLR was significantly associated with SB (β=0.489, p=0.000; odds ratio [95% confidence intervals]=1.631 [1.266-2.102]). We propose a cut-off value of NLR=1.30 (sensitivity=75% and specificity=35%). Our data suggest that NLR may be a valuable, reproducible, easily accessible, and cost-effective strategy to determine suicide risk in MDD.

Highlights

Suicide is a pressing public health problem
Our objective is to investigate the association among Neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), and platelet-to-lymphocyte ratio (PLR) and history of suicide attempt (SA) in patients with major depressive disorder (MDD), controlling for different potential confounding variables, in order to help determine the possible role of these ratios in predicting suicidal behavior (SB)
All patients included in the study were experiencing an active episode of depression with a score of 7 or more on the Hamilton Depression Rating Scale (HDRS) scale

Summary

Introduction

Suicide is a pressing public health problem. On an average, 1 million people commit suicide each year worldwide, and suicide is the second leading cause of death in the 15–29-year age group. The aim of this study is to evaluate the association among NLR, MLR, and PLR and SB in patients with major depressive disorder (MDD), and to test its validity as a biomarker for suicidality. A logistic regression model was estimated to determine the independent factors associated with suicide risk in patients with and without a history of suicide attempt (SA). Patients with a previous SA were more frequently female (71.9% vs 59.6%; p = 0.007), significantly younger (41.20 vs 51.77 years; p < 0.001), had lower depression severity at enrolment (15.58 vs 18.42; p < 0.000), and significantly higher mean NLR and PLR ratios (2.27 vs 1.68, p = 0.001; 127.90 vs 109.97, p = 0.007, respectively). Our data suggest that NLR may be a valuable, reproducible, accessible, and cost-effective strategy to determine suicide risk in MDD

Objectives

Methods

Results