Relationship of PLR, NLR and LMR with Metabolic Syndrome in Schizophrenic Patients on Antipsychotics: A Longitudinal Case-control Study

Abstract

Introduction: Cytokines are the small cell signalling proteins like granulocytes, lymphocytes, monocytes, etc. which may indirectly play a role in the pathophysiology of schizophrenia via inflammation. Neutrophil-to-Lymphocyte Ratio (NLR), Lymphocyte-to-Monocyte Ratio (LMR) and Platelet-to-Lymphocyte Ratio (PLR) are consistently used as a biomarkers for the innate immunity. Metabolic syndrome has been established as a serious public health concern over the last decade with increased morbidity associated with it. However, data regarding changes in LMR and PLR in metabolic syndrome is sparse. Therefore, the relationship between metabolic syndrome and raised inflammatory markers is not established. Aim: To find out the relationship between inflammatory markers and metabolic syndrome in patients of schizophrenia and normal population. Materials and Methods: A case-control study was conducted in the Department of Psychiatry, Sanjay Gandhi Memorial Hospital, Rewa, Madhya Pradesh, India, between February 2019 and January 2020. The study consisted of 84 schizophrenic patients from Inpatient and Outpatient Departments and 100 healthy controls from the general population, and data were collected using semi-structured proforma. Participants were evaluated for Complete Blood Count (CBC), parameters of metabolic syndrome (systolic and diastolic blood pressure; high density lipoprotein; triglycerides; fasting blood glucose; waist circumference) and severity of symptoms using Brief Psychiatric Rating Scale (BPRS). Data was analysed using IBM Statistical Package for the Social Sciences (SPSS) version 22.0 by Student’s t-test, one way Analysis of Variance (ANOVA), repeated measure ANOVA, Spearman’s rho correlation and linear regression analysis. Results: The mean age of cases and controls was 31.4±11.9 years and 35.4±14.1 years, respectively. There were 54 (64.3%) males and 30 (35.7%) females in cases and 62 (62%) males and 38 (38%) females in controls. There was a significant difference between cases and controls for LMR, and NLR at baseline and four months (p-value <0.01). There a was significant difference between two antipsychotics group for NLR and PLR at baseline, two months, and four months (p-value <0.01) with moderate to large effect size. There was a significant correlation between metabolic syndrome and LMR, NLR and PLR for cases as well as controls (p-value <0.05). Conclusion: The study established the alteration of NLR, LMR and PLR in patients of schizophrenia, and also established a relationship between MetS and inflammatory markers which suggested some common pathway between inflammation, metabolic syndrome and schizophrenia.

Keywords

• blood parameters
• lymphocyte-to-monocyte ratio
• neutrophil-to-lymphocyte ratio
• platelet-to-lymphocyte ratio
• risk factor