Objective: Impulsivity is a multidimensional construct consistently associated with problematic substance use, but less is known about its relevance to clinical outcomes. The current study examined whether impulsivity changed over the course of addiction treatment and whether the changes were associated with changes in other clinical outcomes.
Method: Participants were patients in a large inpatient addiction medicine program (N = 817; 71.40% male). Impulsivity was assessed using a self-report measure of delay discounting (i.e., overvaluation of smaller immediate rewards) and the UPPS-P Impulsive Behavior Scale, a self-report measure of impulsive personality traits. Outcomes were psychiatric symptoms including depression, anxiety, posttraumatic stress disorder, and drug cravings.
Results: Within-subjects analyses of variance revealed significant within-treatment changes in all UPPS-P subscales, all psychiatric indicators, and craving (ps < .005), but not delay discounting. Changes in all UPPS-P traits, except for sensation seeking, were significantly positively associated with changes in psychiatric symptoms and cravings over the course of treatment (ps < .01).
Conclusions: These findings reveal that facets of impulsive personality change across addiction treatment and are generally related to positive changes in other clinically relevant outcomes. Evidence of change despite no explicit intervention targeting suggests that impulsive personality traits may be viable treatment targets in substance use disorder treatment.