3 - (SYM 46) Intolerance of Uncertainty Improves After Treatment for Hoarding Disorder

Abstract: Hoarding disorder (HD) is an impairing condition characterized by the accumulation of large amounts of clutter. Treatments have been developed for HD, including cognitive-behavioral therapy (CBT) and facilitated help groups. However, these treatments are not universally effective and typically only lead to a partial reduction in hoarding symptoms. Improving our knowledge of the factors that contribute to hoarding problems may represent an important avenue to improve interventions, as these factors may also represent potential treatment mechanisms. One factor that has been linked to hoarding symptoms is intolerance of uncertainty (IU), the dispositional tendency to fear the unknown. Research has not yet investigated whether IU may be a factor relevant to treatment outcomes for HD. Therefore, the present study administered the Intolerance of Uncertainty Scale (IUS) to a sample of patients diagnosed with HD before and after completing a standardized treatment protocol consisting of a short-term, manualized skills group that uses CBT principles but is led by non-professional facilitators (the Buried in Treasures [BIT] Workshop), with additional supervised in-home uncluttering practice. The sample (n=41) included 66% women and was 74% Caucasian; mean age was 56.1 years (range 24-70) consistent with other HD treatment studies. Hoarding symptom severity was quantified with the Saving Inventory-Revised (SI-R), administered at baseline and after 18 weeks of treatment. Pre-treatment IUS scores did not significantly predict improvement in hoarding symptoms (β = .15, p = .31). However, paired samples t-tests revealed that IUS scores were significantly reduced from baseline to post-treatment (t=2.23, p< .05). Moreover, residualized change scores on the IUS significantly predicted hoarding symptom outcomes: controlling for baseline SI-R severity, change in IUS accounted for 14.7% of the variance in post-treatment SI-R scores (β = .41, p < .001). Specifically, greater reduction in IU uniquely predicted better hoarding symptom outcomes. These results suggest that high initial levels of IU may not prevent patients from benefiting from hoarding treatment, and that reduction in IU accounts for a significant increment in hoarding treatment gains. Results will be discussed in terms of relevance to understanding mechanisms involved HD treatment towards treatment refinement. Limitations will be discussed.