Suicidality and substance abuse in affective disorders.

The relationship between suicidality and substance abuse has long been recognized, although studies have only fairly recently begun to identify factors that may help clarify how alcohol or other drug abuse increases the susceptibility to suicidal behavior in vulnerable populations. In particular, alcohol and other psychoactive substance misuse has been linked with mood destabilization and the induction of manic or depressive episodes in affectively ill individuals, while also demarcating groups with heightened tendencies toward impulsivity, aggression, and sensitivity to interpersonal loss. Serotonergic mechanisms have been implicated in each of these clinical settings, along with possible dysregulation of other neurotransmitter systems. Psychosocial aspects of alcohol or drug abuse relevant to suicide may involve a heightened sensitivity to interpersonal loss, poor coping skills in response to adverse life events, and affective dysregulation induced by circadian and psychosocial stresses. Consequently, self-destructive behaviors with relatively little premeditation may arise during periods of increased stress, intoxication, depression, or other psychopathology. Early detection of substance abuse followed by appropriate pharmacologic and/or psychotherapeutic interventions may greatly help to minimize the formation of complex comorbid psychiatric conditions and reduce the potential for suicidal acts among high-risk populations.