Elevated attentional and nonplanning impulsivity, as scored by the BIS-11, have been observed during depressive episodes and correlate with depressed mood; impulsivity also correlates with hopelessness, anhedonia, and suicidality (Swann et al., 2008). In this way, impulsivity may interact with depression to increase the risk of suicide. Simon and colleagues (2001) reports that medically severe impulsive suicide attempts were more likely to involve violent methods even though actual suicidal intent was milder than in planned attempts. This reflects the dissociation between behavior and conscious intention that characterizes impulsivity. Impulsive attempters were less likely to be depressed, but equally likely to experience hopelessness, compared to nonimpulsive attempters. This is consistent with the characteristics of impulsivity as reflected by the subscales of the BIS-11 score: lack of capacity for cognitive complexity (attentional impulsivity) leading to poor problem solving and low resilience, and a lack of sense of the future (nonplanning impulsivity) (Stanford et al., 2009). Among individuals with diagnoses of bipolar disorder, elevated BIS-11 scores and rapid-response impulsivity were associated with a history of having made a suicide attempt. Severity of the most recent past attempt was related to rapid-response behaviors, but not BIS-11 scores (Swann et al., 2005b).
