Acceptance And Commitment Therapy And Heavy Episodic Drinking Among College Students: An Examination Of Mechanisms Of Change

Acceptance and Commitment Therapy (ACT) is a third-wave behavioral therapy that uses acceptance- and mindfulness-based interventions. The main target of ACT is increasing psychological flexibility. While ACT has been shown to be effective in treating substance use, little research has focused on the mechanisms of change in ACT and substance use. The present study examined if psychological flexibility, distress tolerance, and mindfulness mediate the effectiveness of an ACT-based intervention compared to a psychodidactic control on heavy episodic drinking and alcohol-related problems among college freshmen. No significant differences emerged between conditions on heavy episodic drinking or alcohol-related problems. However, participants in both conditions reported decreased heavy drinking and related problems across time. Indirect analyses indicated a lack of differences between conditions on mediator variables, although there were increases in psychological flexibility, distress tolerance, and mindfulness across time. Psychological flexibility, distress tolerance, and nonjudgment of inner experience were negatively associated with alcohol-related problems. These findings suggest that preventive interventions can impact college student alcohol use and related problems as well as transdiagnostic mechanisms. Future research should examine ACT as a targeted, rather than prevention-focused, intervention for substance use in college students, particularly focusing on transdiagnostic mechanisms of change for substance use.