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

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).

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.

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.

Reported findings may or may not apply consistently in other cultures and locations.

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.