Genetic liability for major depression increases risk for suicide attempt across psychiatric disorders, a new study suggests. The genome-wide association study (GWAS) on suicide attempt used cohorts of individuals with major depressive disorder (MDD), bipolar disorder, and schizophrenia from the Psychiatric Genomics Consortium. The samples comprised 1,622 suicide attempters and 8,786 nonattempters with MDD, 3,264 attempters and 5,500 nonattempters with bipolar disorder, and 1,683 attempters and 2,946 nonattempters with schizophrenia. Researchers found:
- 3 genome-wide significant loci for suicide attempt were found: 1 associated with suicide attempt in MDD, 1 associated with suicide attempt in bipolar disorder, and 1 in the meta-analysis of suicide attempt in mood disorders.
- No significant associations were found in the meta-analysis of all 3 disorders.
- Polygenic risk scores for MDD were significantly associated with suicide attempt in MDD, bipolar disorder, and schizophrenia.
Mullins N, et al. GWAS of suicide attempt in psychiatric disorders and association with major depression polygenic risk scores. [Published online ahead of print June 5, 2019]. Am J Psychiatry. doi: 10.1176/appi.ajp.2019.18080957.
This paper by Mullins et al. is one of the largest studies looking to see if there are clear genetic findings, or predispositions that lead more often to suicide attempts. Their key finding is that where genetic liability for major depression increases so does the risk for a suicide attempt in major depressive disorder, bipolar disorder, and schizophrenia. Therefore, it is not clear still if suicidality has its own genetic risks but rather the presence of genetic risk for depression may lead more often to suicide attempts regardless of the psychiatric disorder at hand. In other words, depressive symptoms may drive the risk for suicide attempt regardless of ultimate DSM-5 diagnosis. With suicide completions increasing ,we must continue to look for these predictors of pending suicide whether it be by using adept clinical interviewing, outcomes-based rating scales, statistical meta-data derived from EMRs, genetic or functional imaging screenings. —Thomas L. Schwartz, MD; Senior Associate Dean of Education, Interim Chair/Professor of Psychiatry, SUNY Upstate Medical University.