Suicidal behavior and inflammation: neutrophil to lymphocyte ratio

BACKGROUND: Inflammation has been found to be associated with mental illness. The neutrophil-to-lymphocyte ratio (NLR) has been suggested to be a new biomarker of low-grade inflammation as well as suicidal ideation. We aimed to investigate the relationship between NLR and suicide attempts.METHODS: This is a retrospective chart review study. A hundred and forty-seven suicide attempters and 91 controls with major depressive disorder in remission were enrolled in the study. Sociodemographic information and hemogram results were tabulated by reviewing medical records.RESULTS: We found statistically significantly higher NLR in suicide attempters (2.843±2.05) compared to controls (1.912±0.83) (P<0.001). There was no statistical difference between adolescent and adult suicide attempters in terms of NLR, sex, suicide method, lethality, living area, or the month of suicide. However, adults attempted suicide mostly in November, and adolescents attempted suicide mainly in March. Overdosing on medication was the most common suicide method for both adolescents and adults.CONCLUSIONS: Elevated peripheral NLR was associated with suicide attempt.