Overarousal interacts with a sense of fearlessness about death to predict suicide risk in a sample of clinical outpatients.

Converging evidence suggests that acute states of overarousal are common prior to suicidal behavior. Yet, there has been very little theory-driven research of these phenomena. We consider two competing theoretical perspectives. The first is consistent with the interpersonal theory of suicide, which suggests that the prospect of engaging in lethal suicidal behavior should elicit some degree of arousal; however, the effect of arousal will be particularly relevant when considered in the context of an individual׳s capability for suicide. The second perspective draws from escape-based models, which would suggest that arousal alone should result in increased suicide risk, given the distress associated with high arousal states. Results indicated that the interaction of overarousal and capability for suicide was associated with suicidal symptoms. As overarousal increased, suicidal symptoms increased among high capability individuals and decreased among low capability individuals. These effects were observed beyond the effects of depression, anxiety, age, gender, and marital status. There was no significant main effect of overarousal. Results support a perspective in line with the interpersonal theory, suggesting that overarousal states may be particularly dangerous for individuals who have developed the capability for suicide.