Hoarding disorder is a new disorder in the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5; American Psychiatric Association, 2013, Sect. 300.3), as well as in the International Classification of Diseases, 11th edition (ICD-11; World Health Organization, 2018, Sect. F42, subsection 6B24), where it is included in the respective “Obsessive-Compulsive and Related Disorders” chapter. However, hoarding behavior is not a new or newly discovered phenomenon.
According to Penzel (2014), there is evidence of hoarding behavior as early as the very beginning of humankind, and classical literature is peppered with references to hoarding, such as in Dante Alighieri’sOpens in new window well-known poem “Inferno”; Gogol’s main character in Dead SoulsOpens in new window from 1842; and Krook, a character in Dickens’ Bleak HouseOpens in new window from 1862.
The word hoarding comes from the word hord in Old English, meaning “treasure, valuable stone or store” (Penzel, 2014).
By definition, Hoarding disorder is characterized by difficulty parting with items because of the need to save them and distress from discarding them, regardless of their value.
Hoarding behavior results in clutter that interferes with the ability to use living spaces as intended, unless someone else intervenes to limit the clutter. The majority (60 – 90%) of individuals with hoarding disorder engage in excessive acquisition of new objects as well, and the clinician can code this (e.g., for billing or research purposes) by specifying “with excessive acquisition” (Frost, Rosenfield, Steketee, & Tolin, 2013).
Hoarding disorder is a new diagnosis in DSM-5 and ICD-11; previously, individuals with hoarding would have been diagnosed with obsessive-compulsive disorder (OCD)Opens in new window or OCPDOpens in new window. In fact, before DSM-5, diagnostic criteria pertaining to hoarding behavior were mentioned in only one section of the DSM: the fifth criterion of OCPD, where “[he or she] is unable to discard worn-out or worthless objects even when they have no sentimental value” (American Psychiatric Association, 2000, p. 729).
Notably, apparent hoarding behavior (e.g., unwillingness to discard, excessive acquisition) can indicate numerous diagnoses, and hoarding disorder is not diagnosed when the symptoms are better accounted for by another condition, including OCD. For example, an individual with excessive clutter because of obsessions related to contamination or because of the need to complete elaborate compulsionsOpens in new window before discarding would be diagnosed with OCD, not hoarding disorder.
Poor insight is common among individuals who hoard, and when coding the diagnosis, the clinician should specify degree of insight. In fact, more than half of individuals with hoarding have poor or delusional levels of insight (Tolin, Frost, & Steketee, 2010). Poor insight can manifest in several ways, including lack of appreciation of the severity of the problem or its impact on related consequences; rigid, fixed, and unreasonable beliefs about possession; and defensiveness (Frost, Tolin, & Maltby, 2010). Degree of insight is a particular concern with this population because low insight has been associated with lack of motivation, treatment dropout, therapy-interfering behaviors, and poor treatment outcome (Frost et al., 2010).
|Table X-1. DSM-5 Diagnostic Criteria for Hoarding Disorder|
|Note Reprinted with permission from the Diagnostic and Statistical Manual of Mental Disorders (5th ed., p. 247). © 2013 American Psychiatric Association. All rights reserved.|
The DSM-5 criteria for hoarding disorder are provided in Table X-1. The ICD-11 criteria for the disorder are similar to those found in DSM-5 and emphasize the accumulation of possessions as a result of difficulty discarding or excessive acquisition, accumulation of belongings that results in the inability to use or remain safe in living spaces, and associated functional impairment and/or distress to the self or others.
There are, however, some important differences between the DSM-5 and ICD-11 criteria for hoarding disorder.
- The most critical difference is that DSM-5 requires the presence of difficulty discarding, often considered the hallmark of the disorder.
- The criteria for ICD-11, however, indicate that one of (a) difficulty discarding, or (b) excessive acquisition is required to explain accumulation of possessions, indicating that a case could be labeled with the diagnosis without the presence of difficulty discarding. In DSM-5, excessive acquisition is a specifier.
- Another important difference is that the ICD-11 does not qualify the requirement for clutter by indicating that a lack of clutter could be the result of intervention from others (e.g., parents picking up a child’s clutter). This could make it more challenging for appropriately diagnosing children and other vulnerable populatiosn who present with bona fide hoarding behavior but have guardians who are consistently stepping in to prevent clutter.
- Another difference between DSM-5 and ICD-11 is that levels of insight are coded in three levels in the former but two levels in the latter, with poor and absent insight collapsed into one level in the ICD-11 hoarding disorder coding scheme.
Estimates of the prevalence of hoarding disorder vary considerably, ranging from 1.5% to 5.8% of the population (Nordsletten, Reichenberg, et al., 2013). Rates are much higher among individuals seeking treatment for anxiety disorders (approximately 12 – 25%; Tolin, Meunier, Frost, & Steketee, 2011). Research is equivocal about potential gender differences, with some studies finding similar rates among men and women, and others finding higher rates in men than women (Iervolino et al., 2009; Samuels et al., 2008).
Course and Prognosis
Hoarding disorder tends to have a chronic and gradually worsening course. Typical age of onset is in adolescence. Considering that the disorder usually does not remit spontaneously, over time clutter accumulates, and both symptoms and their sequelae become more severe.
Therefore, older adults have higher rates and more severe cases of hoarding. For this reason, most of the time, those who seek treatment for hoarding are older. Hoarding disorder is also associated with marital status (not being married) and with several negative outcomes, including unemployment and poor reported health (Nordsletten, Reichenberg, et al., 2013).
- Gregory S. Chasson, Jedidiah Siev, Advances in Psychotherapy-Evidence-Based Practice: Hoarding Disorder.