An investigation of the role of intolerance of uncertainty in hoarding symptoms.

Background: Hoarding disorder (HD) is a common, debilitating mental illness and public health burden. Understanding the factors that contribute to hoarding is critical for identifying treatment targets. As a relatively new diagnostic entity, this research remains in its initial stages. Intolerance of uncertainty (IU) is thought to be a vulnerability factor for generalized anxiety disorder (GAD) and obsessive-compulsive disorder (OCD), and may also be relevant to HD. We investigated the possible association between IU and hoarding in two sets of analyses.

Method: First, we administered self-report measures of IU and hoarding symptoms to unscreened undergraduate students (N=456) and used regressions to probe their association controlling for relevant covariates. Second, in a clinical sample, we compared IU across groups of patients with HD (N=26), GAD (N=26), OCD (N=51), other anxiety disorders (N=91) and healthy controls (N=29).

Results: In the student sample, IU predicted hoarding symptoms above and beyond relevant covariates, including hoarding-related beliefs. In the clinical sample, HD patients evidenced greater IU relative to healthy individuals and the mixed anxiety group, and comparable levels of IU to the GAD and OCD groups.

Limitations: This study relied exclusively on self-report questionnaires and a cross-sectional design.

Conclusions: IU is associated with hoarding behavior and, as we discuss, conceptual models might benefit from the study of IU as a potentially contributing factor. Directions for future research are discussed.