When hoarding is a symptom of OCD: a case series and implications for DSM-V.

Hoarding, the excessive collection and failure to discard objects of apparently little value, can represent a serious psychiatric problem and pose a threat to public health. Hoarding has traditionally been considered a symptom (or symptom dimension) of Obsessive-Compulsive Disorder (OCD), but its nosological status has recently been debated. Mounting evidence suggests that, once other primary causes are ruled out, hoarding may be a discrete diagnostic entity, recently named Hoarding Disorder. However, hoarding can sometimes be a genuine OCD symptom. This can be confusing and clinicians may sometimes struggle making the differential diagnosis. To illustrate this, we describe 10 OCD patients with severe hoarding behavior that is better conceptualized as a symptom of OCD. We focus on the motivations for hoarding and the overlapping of hoarding with other obsessive-compulsive symptom dimensions. We estimate that this clinical presentation is relatively rare and accounts for a minority of severe hoarding cases. We discuss the unique characteristics of hoarding as a symptom of OCD and the implications for DSM-V.