Relevance of Family History of Suicide in the Long-Term Outcome of Bipolar Disorders

Objective: This study examined the association between family history of completed suicide and suicidal behavior and other clinical variables in subjects with bipolar disorder.

Method: 374 outpatients aged from 19 to 88 years (mean ± SD age = 41.9 ± 4.1 years) (54.3% female) meeting DSM-IV criteria for bipolar disorder type I or II or schizoaffective disorder, bipolar subtype, were included in the study. Forty-eight subjects with a family history of completed suicide were compared to 326 subjects without a family history of completed suicide regarding several clinical and demographic variables. The study was conducted from 2001 to 2004.

Results: There were no statistically significant demographic differences between bipolar disorder subjects with and without a family history of suicide. Bipolar disorder subjects with a family history of suicide showed higher rates of cluster C personality disorders than subjects without a family history of suicide (14.9% vs. 2.5%, OR = 6.72, 95% CI = 2.31 to 19.51, p < .001). Subjects with a family history of suicide also demonstrated a significantly greater lifetime prevalence of suicide attempts (52.2% vs. 25.5%, OR = 3.19, 95% CI = 1.7 to 6.0, p < .001). Results remained significant after controlling for all possible interactions.

Conclusion: Family history of completed suicide is a significant risk factor associated with suicidal attempts in patients with bipolar disorder. These findings underscore the importance of identifying patients with a family history of suicide in order to provide prompt treatment and careful follow-up.