One position is that compulsive

hoarding should be included in our diagnostic system as an independent syndrome, which is sometimes comorbid with OCD. Including hoarding as a separate syndrome has a number of important practical advantages, well-summarized by Rachman and colleagues.21 For example, it would expand the boundaries of the hoarding population to be consistent with the data showing a high incidence of hoarding not associated with OCD. It would also encourage clinicians and researchers to use hoarding-specific assessment tools rather than measures designed for OCD, and facilitate the development of new treatment Inhibitors,research,lifescience,medical methods for hoarding. Another possibility is that hoarding may be listed in DSM-5 as both a separate syndrome and as an OCD symptom. Epidemiology Hoarding researchers also have made substantial progress in understanding the Inhibitors,research,lifescience,medical prevalence and manifestation of compulsive hoarding in the population. Until very recently, researchers estimated

the prevalence of hoarding as a subportion of individuals with OCD in the community.22 Similarly, information regarding the burden of hoarding was based on anecdotal evidence and small samples. Recent epidemiological studies, however, suggest that compulsive hoarding may be far more prevalent and burdensome Inhibitors,research,lifescience,medical in the community than previously thought. Data from the Baltimore Epidemiologic Inhibitors,research,lifescience,medical Catchment Area Follow-up survey suggest that 5% of the general population experiences clinically significant hoarding, while data from the National Comorbidity Survey Replication indicate that the lifetime prevalence of compulsive hoarding may be as high as 14%.23,24 These studies estimated hoarding based upon reports of difficulty

discarding, and did not specifically target clutter and excessive acquisition, and thus it is unknown whether cases met criteria for compulsive hoarding as defined by Frost and Hart.11 A recent twin study that utilized a self -report instrument to assess the broad hoarding phenotype found that Inhibitors,research,lifescience,medical 2% of its sample reported clinically significant hoarding symptoms.25 As symptom severity obtained by self-report tends to be lower than clinician-rated severity, the current prevalence of clinically significant compulsive hoarding may be somewhere between 2% and 5%. Importantly, mafosfamide a large proportion of individuals who hoard report having at least one first-degree relative who experiences hoarding problems.3,14 In a sample of individuals with OCD, Samuels and colleagues14 reported that probands of individuals with hoarding symptoms were four times more likely to experience hoarding symptoms than probands of individuals who did not report hoarding symptoms. Genetic factors and inhibitors purchase unshared environmental factors may explain this familial connection.