Completed suicide in bipolar disorder patients: A cohort study after first hospitalization

Background: Bipolar disorder (BD) is a mental health condition that has one of the greatest risk of completed suicide (CS). Hospitalization in affective disorders is associated with increased illness severity and suicide risk, so the study of suicide after the first hospitalization is of special interest.

Method: We studied a retrospective cohort consisting on all BD type I (BD-I) and II (BD-II) (according to DSM-IV criteria) admitted for the first time in their lives to the psychiatry unit of a general hospital between 1996 and 2016 from an area in Catalonia (Spain). All patients were also followed-up in a community center of mental health as outpatients until the end of 2017. Multiple variables were prospectively collected during the first hospital admission and were compared between patients who CS and those who did not.

Results: 14 of 313 (4.5%) bipolar patients included CS during the 11-year follow-up, and 93% used a violent method. In the univariate analysis we found that Bipolar II Disorder, treatment with antidepressants and/or with lamotrigine were associated with higher risk of CS, however, treatment with valproate and/or with antipsychotics were associated with lower risk of CS . After logistic regression multivariant analysis, only immediately previous violent suicide attempt and first-degree family history of CS remain significant risk factors of CS. A limitation is the relatively small sample from a local hospital and followed locally.

Conclusion: Followed during an average of 11 years after the first hospital admission, Bipolar patients completed suicide at a rate 58 times higher than the general population and almost always performed through a violent method. Violent attempted suicide before admission and first- degree family history of CS, are clear and potent predictors of completed suicide.