Leo Sher, M.D.

Our research article, “Neuropeptide Y plasma levels and suicidal behavior in combat veterans” has been published in European Neuropsychopharmacology online ahead of print (1). We examined whether levels of plasma neuropeptide Y (NPY) might distinguish combat veterans who have made a post-deployment suicide attempt from those who have never made a suicide attempt. We focused on NPY because of prior findings linking NPY with the neurobiology of resilience, stress-related and other disorders, and suicidal behavior.

A trained clinician interviewed all veterans who participated in the study. Demographic and clinical parameters of suicide attempters and non-attempters were assessed and recorded. Suicide attempters and non-attempters were matched with regard to psychiatric diagnoses. Plasma NPY was determined by radioimmunoassay.

NPY levels were higher among attempters in comparison to non-attempters, controlling for sex and body-mass index. Suicide attempters had higher Scale for Suicidal Ideation (SSI) scores than non-attempters. There was a trend towards higher Montgomery-Åsberg Depression Rating Scale (MADRS) scores in the suicide attempter group compared to non-attempters. There was a positive correlation between NPY levels and SSI scores among non-attempters but not among attempters. NPY levels positively correlated with Brown-Goodwin Aggression Scale scores among suicide attempters but not among non-attempters.

Our study is the first demonstration of altered plasma NPY levels in association with suicide attempt history and suicidal ideation in veterans. Further studies of the role of NPY in the neurobiology of suicidal behavior may contribute to our understanding of the neurobiology of suicide.

Reference

1. Sher L, Bierer LM, Flory J, Makotkine I, Yehuda R. Neuropeptide Y plasma levels and suicidal behavior in combat veterans. Eur Neuropsychopharmacol. 2020 Jun 24:S0924-977X(20)30191-7. doi: 10.1016/j.euroneuro.2020.06.003. Online ahead of print.