Efficacy and Mediators of a Group Cognitive-Behavioral Therapy for Hoarding Disorder: A Randomized Trial.

Objective: Hoarding disorder (HD) is a common and potentially debilitating psychiatric disorder. Thus far, psychological treatments have yielded modest effects and/or were time-consuming and costly to deliver. The aim of the present study was to test the efficacy of a brief group cognitive-behavioral therapy (CBT) for adults with HD and to test hypothesized mediators of treatment outcome. Method: Eighty-seven adults with a primary diagnosis of HD were randomized to either immediate CBT or wait list. CBT consisted of 16 weekly, 90-min group sessions that emphasized in-session practice of discarding and refraining from acquiring, decision-making and problem-solving training, emotional distress tolerance, motivational interviewing strategies, and contingency management. Participants were assessed at pretreatment, midtreatment, and posttreatment by an independent evaluator unaware of treatment condition. Results: CBT was efficacious for the symptoms of HD compared with wait list. Saving-related cognitions, but not subjective cognitive impairment, partially mediated treatment outcomes. Conclusion: Brief Group CBT is an efficacious and feasible treatment for adults with HD, and is partially mediated by reductions in maladaptive beliefs about possessions. Superiority trials comparing CBT to active treatments, and additional research into mechanisms of treatment outcome, are warranted. [ABSTRACT FROM AUTHOR]