Suicidal risk and protective factors in major affective disorders: A prospective cohort study of 4307 participants

Background: Suicidal behavior is strongly associated with major affective disorders, but there is a need to quantify and compare specific risk and protective factors in bipolar disorder (BD) and major depressive disorder (MDD). Methods: In 4307 extensively evaluated major affective-disorder participants with BD (n = 1425) or MDD (n = 2882) diagnosed by current international criteria, we compared characteristics among those with versus without suicidal acts from illness-onset through 8.24 years of follow-up. Results: Suicidal acts were identified in 11.4 % of participants; 25.9 % were violent and 6.92 % (0.79 % of all participants) were fatal. Associated risk factors included: diagnosis (BD > MDD), manic/psychotic features in first-episodes, family history of suicide or BD, separation/divorce, early abuse, young at illness-onset, female sex with BD, substance abuse, higher irritable, cyclothymic or dysthymic temperament ratings, greater long-term morbidity, and lower intake functional ratings. Protective factors included marriage, co-occurring anxiety disorder, higher ratings of hyperthymic temperament and depressive first episodes. Based on multivariable logistic regression, five factors remained significantly and independently associated with suicidal acts: BD diagnosis, more time depressed during prospective follow-up, younger at onset, lower functional status at intake, and women > men with BD. Limitations: Reported findings may or may not apply consistently in other cultures and locations. Conclusions: Suicidal acts including violent acts and suicides were more prevalent with BD than MDD. Of identified risk (n = 31) and protective factors (n = 4), several differed with diagnosis. Their clinical recognition should contribute to improved prediction and prevention of suicide in major affective disorders.