Temperament, Character, and Suicide Attempts in Unipolar and Bipolar Mood Disorders

Objective: Personality features may indicate risk for both mood disorders and suicidal acts. How dimensions of temperament and character predispose to suicide attempts remains unclear.

Method: Patients (n = 597) from 3 prospective cohort studies (Vantaa Depression Study [VDS], Jorvi Bipolar Study [JoBS], and Vantaa Primary Care Depression Study [PC-VDS]) were interviewed at baseline, at 18 months, and, in VDS and PC-VDS, at 5 years (1997-2003). Personality was measured with the Temperament and Character Inventory-Revised (TCI-R), and follow-up time spent in major depressive episodes (MDEs) as well as lifetime (total) and prospectively ascertained suicide attempts during the follow-up were documented.

Results: Overall, 219 patients had 718 lifetime suicide attempts; 88 patients had 242 suicide attempts during the prospective follow-up. The numbers of both the total and prospective suicide attempts were associated with low self-directedness (β = -0.266, P = .004, and β = -0.294, P < .001, respectively) and high self-transcendence (β = 0.287, P = .002, and β = 0.233, P = .002, respectively). Total suicide attempts were linked to high novelty seeking (β = 0.195, P = .05). Prospective, but not total, suicide attempts were associated with high harm avoidance (β = 0.322, P < .001, and β = 0.184, P = .062, respectively) and low reward dependence (β = -0.274, P < .001, and β = -0.134, P = .196, respectively), cooperativeness (β = -0.181, P = .005, and β = -0.096, P = .326, respectively), and novelty seeking (β = -0.137, P = .047). No association remained significant when only prospective suicide attempts during MDEs were included. After adjustment was made for total time spent in MDEs, only high persistence predicted suicide attempts (β = 0.190, P < .05). Formal mediation analyses of harm avoidance and self-directedness on prospectively ascertained suicide attempts indicated significant mediated effect through time at risk in MDEs, but no significant direct effect.

Conclusions: Among mood disorder patients, suicide attempt risk is associated with temperament and character dimensions. However, their influence on predisposition to suicide attempts is likely to be mainly indirect, mediated by more time spent in depressive episodes.