Leo Sher, M.D.

Our research report, “Plasma testosterone levels and subsequent suicide attempts in males with bipolar disorder” has been published in Acta Psychiatrica Scandinavica online ahead of print (1). In this study, we examined whether higher testosterone levels predict future suicide attempts in males with bipolar disorder and a history of suicide attempt.

Sixteen male suicide attempters with bipolar disorder were included in the study. Four of them made suicide attempts during the follow-up period. We limited this study to previous suicide attempters in order to have a high-risk group for suicide attempt on follow-up and thereby enhancing statistical power. Hamilton Depression Rating Scale (HDRS), Aggression History Scale (Brown-Goodwin, revised), Barratt Impulsivity Scale, Buss-Durkee Hostility Inventory, Scale for Suicide Ideation, the Beck Hopelessness Scale, Medical Lethality Rating Scale, and Reasons for Living Inventory were used to evaluate study participants. Baseline plasma testosterone was assayed using a radioimmunoassay procedure. Patients were followed up prospectively for up to 2.5 years.

At baseline, males with bipolar disorder who made suicide attempts during the follow-up period had significantly higher testosterone levels in comparison with those who did not attempt suicide during the follow-up interval. The mean interval of prospective observation between the enrollment in the study and the first suicide attempts was 500.2 ± 269.4 days. Higher baseline testosterone levels predicted suicide attempts during the follow-up period. An increase in the testosterone level by 1 ng/ml increased the probability of suicide attempt almost twofold.

Our finding that higher baseline plasma testosterone levels predicted suicide attempts during the follow-up period is in agreement with studies implicating testosterone in the neurobiology of suicidal behavior. It is to be hoped that this work will stimulate future research with important therapeutic implications.

Reference

1. Sher L, Sublette ME, Grunebaum MF, Mann JJ, Oquendo MA. Plasma testosterone levels and subsequent suicide attempts in males with bipolar disorder. Acta Psychiatr Scand. 2021 Nov 4. doi: 10.1111/acps.13381. Epub ahead of print.