Predisposition for Self-Destruction? Affective Temperaments as a Suicide Risk Factor in Patients With Mood Disorders

Abstract

Because suicide is overall a relatively rare event, its prediction in individual cases remains very difficult. Suicidal behavior (both fatal and nonfatal) is, however, quite frequent among psychiatric patients who have contacted different levels of the health-care system some weeks or months before their attempt (Luoma, Martin, & Pearson, 2002). Untreated unipolar or bipolar major depressive episode is the main clinical substrate of suicide, accounting for 56–87% of the cases. What is most important in this respect is that suicidal behavior in mood disorder patients is a phenomenon dependent on the state and severity of the underlying disease, and that suicidality decreases/vanishes after clinical recovery (Rihmer, 2007). But because the majority of depressed patients never complete suicide and about half of them never attempt it, special clinical, psychological, and psychosocial risk factors also play a significant role (Rihmer, 2007). A look at these factors may help us to identify patients who are at an especially high risk for suicide. As to psychological characteristics, it has been well known for many decades that suicidality is also associated with certain personality features, such as aggressive/impulsive traits, hopelessness and pessimism, and that the risk increases if these traits are present in combination (Mann, Waternaux, Haas, & Malone, 1999; Oquendo et al., 2004; MacKinnon et al., 2005). Impulsivity, a characteristic trait in bipolar patients, has been associated with nonlethal suicide attempts in general samples, and in affective patients it is also associated with severe suicide attempts and completed suicide (Swann et al., 2005). Impulsivity distinguishes suicidal and nonsuicidal affective inpatients and controls, and in bipolar patients suicidal intent is correlated with impulsivity even when controlling for aggression. Impulsivity increases suicide risk when combined with depression; even modest manic symptoms during bipolar depressive episodes are associated with a greater level of impulsivity and higher rate of suicide attempts (Swann et al., 2007). In the case of bipolar disorder, suicidal behavior was also associated with aggressive traits (Grunebaum et al., 2006). Bipolar patients with family history of suicidal behavior and exposed to childhood physical and/or sexual abuse are at greater risk for suicide attempts (Carballo et al, 2008), and impulsivity seems to be the link between childhood abuse and suicidal behavior (Braquehais, Oquendo, Baca-Garcia, & Sher, 2010). In a study on bipolar patients, harm avoidance and persistence as measured by Cloninger’s TCI were significantly related to prior suicide attempts (Engstrom, Brandstrom, Sigvardsson, Cloninger, & Nylander, 2004). Hostility was also found to be a risk factor for suicide attempt, with reasons for living being an important protective factor in bipolar disorder (Chaudhury et al., 2007). Only in the last decade, however, has it become clear that affective temperaments – known to be subclinical manifestations and precursors of major mood disorders – also predispose risk for suicidal behavior. Classically, temperament has included the temporally stable biological “core” of an individual’s personality and plays a role in establishing activity level, rhythms, moods, and related cognitions as well as their variability. Personality, on the other hand,