Compulsive hoarding (or pathological collecting, or, informally, packratting) is a pattern of behavior that is characterized by the excessive acquisition of and inability or unwillingness to discard large quantities of objects that cover the living areas of the home and cause significant distress or impairment. Compulsive hoarding behavior has been associated with health risks, impaired functioning, economic burden, and adverse effects on friends and family members. When clinically significant enough to impair functioning, hoarding can prevent typical uses of space so as to limit activities such as cooking, cleaning, moving through the house, and sleeping. It can also be dangerous if it puts the individual or others at risk from fire, falling, poor sanitation, and other health concerns.
According to Mayo Clinic, "Hoarding isn't yet considered an official, distinct disorder," and many people who hoard don't have (other) OCD-related symptoms. In fact, the term "compulsive hoarding" is the result of older diagnostic schemes that put hoarding fully within obsessive-compulsive disorder (OCD) and may soon become obsolete. Researchers have only recently begun to study hoarding. It is not clear whether "compulsive" hoarding is a separate, isolated disorder, or rather a symptom of another condition, such as OCD. Prevalence rates have been estimated at 2-5% in adults, though the condition typically manifests in childhood with symptoms worsening in advanced age when collected items have grown excessive and family members who would otherwise help to maintain and control the levels of clutter either die or move away. Hoarding appears to be more common in people with psychological disorders such as depression, anxiety and attention-deficit hyperactivity disorder. Other factors often associated with hoarding include alcohol dependence as well as paranoid, schizotypal, and avoidant traits. Family histories show strong positive correlations.
In 2008 a study was conducted to determine if there is a significant link between hoarding and interference in occupational and social functioning. Hoarding behavior is often so severe because of poor insight of the hoarding patients (they do not recognize it as a problem). Without insight into what the problem is, it is much harder for behavioral therapy to be the key to the successful treatment of compulsive hoarders. The results found that hoarders were significantly less likely to see a problem in a hoarding situation than a friend or a relative might. This is independent of OCD symptoms as patients with OCD are often very aware of their disorder.
- A few symptoms hoarders might experience are:
- 1. They tend to hold onto a large number of items that most people would consider not useful or valuable. For example:
- 2. The home is so cluttered that many parts are inaccessible and can no longer be used for intended purpose. For example:
- Beds that cannot be slept in
- Kitchens that cannot be used for food preparation, refrigerators filled to the brim with rotting food, stovetops with combustibles such as junk mail as well as old food piled on top of burners.
- Tables that cannot be used for dining
- Chairs or sofas that cannot be used
- Filthy unsanitary bathrooms; piles of human feces collected in areas of the home, sometimes there are animal feces over the floors of the home, giant bags of dirty diapers hoarded for many years.
- Tubs, showers, and sinks filled with items such that they can not be used for washing or bathing. Hoarders would thus possibly forgo bathing.
- Some hoard animals they cannot even marginally care for; often dead pets cannibalized by other pets are found under the heaps.
- 3. The clutter and mess is so bad it causes illness, distress, and impairment. For example, they:
- Do not allow visitors such as family and friends, or repair and maintenance professionals because the clutter embarrasses them.
- Keep the shades drawn so no one can see inside
- Get into a lot of arguments with family members about the clutter
- Are at risk of fire, falling, infestation or eviction
- Feel depressed or anxious much of the time because of the clutter
- Persistent difficulty discarding or parting with possessions, regardless of the value others may attribute to these possessions. (The Work Group is considering alternative wording: "Persistent difficulty discarding or parting with possessions, regardless of their actual value.")
- This difficulty is due to strong urges to save items and/or distress associated with discarding.
- The symptoms result in the accumulation of a large number of possessions that fill up and clutter active living areas of the home or workplace to the extent that their intended use is no longer possible. If all living areas become decluttered, it is only because of the interventions of third parties (e.g., family members, cleaners, authorities).
- The symptoms cause clinically significant distress or impairment in social, occupational, or other important areas of functioning (including maintaining a safe environment for self and others).
- The hoarding symptoms are not due to a general medical condition (e.g., brain injury, cerebrovascular disease).
- The hoarding symptoms are not restricted to the symptoms of another mental disorder (e.g., hoarding due to obsessions in Obsessive-Compulsive Disorder, decreased energy in Major Depressive Disorder, delusions in Schizophrenia or another Psychotic Disorder, cognitive deficits in Dementia, restricted interests in Autism Spectrum Disorder, food storing in Prader–Willi syndrome).
Understanding the age of onset of hoarding behavior can help develop methods of treatment for this “substantial functional impairment”. Hoarders are dangers to not only themselves, but others as well. The prevalence of compulsive hoarding in the community has been estimated at between two and five percent, significantly higher than the rates of OCD and other disorders, such as panic disorder and schizophrenia.
751 people were chosen for a study in which the persons self-reported their hoarding behavior. Of these individuals, most reported the onset of their hoarding symptoms between the ages of 11 and 20 years old, with 70% reporting the behaviors before the age of 21. Fewer than 4% of people reported the onset of their symptoms after the age of 40. The data show that compulsive hoarding begins early, but often does not become more prominent until after age 40. Different reasons have been given for this such as the presence of family members is more prominent early in life and limits acquisition and facilitates the removal of clutter. The understanding of early onset hoarding behavior may help in the future to be able to distinguish hoarding behavior from “normal” childhood collecting behaviors.
A second key part of this study was to determine if stressful life events are linked to the onset of hoarding symptoms. Similar to self-harming, traumatized persons may create "a problem" for themselves in order not to face their real anxiety or trauma and do something about it. Facing their real issues may be too difficult for them, so they "create" a kind of "artificial" problem (in their case, hoarding) and prefer to battle with it rather than determine, face, or do something about their real anxieties. Hoarders may suppress their psychological pain by "hoarding". The study shows that adults who hoard report a greater lifetime incidence of having possessions taken by force, forced sexual activity as either an adult or a child, including forced intercourse, and being physically handled roughly during childhood, thus proving traumatic events are positively correlated with the severity of hoarding. For each five years of life the participant would rate from 1 to 4, 4 being the most severe, the severity of their hoarding symptoms. 548 participants reported a chronic course, 159 an increasing course and 39 people, a decreasing course of illness. The incidents of increased hoarding behavior were usually correlated to five categories of stressful life events.
Brain imaging studies using positron emission tomography (PET) scans that detect the effectiveness of long-term treatment have shown that the cerebral glucose metabolism patterns seen in OCD hoarders were distinct from the patterns in non-hoarding OCD. The most notable difference in these patterns was the decreased activity of the dorsal anterior cingulate gyrus, a part of the brain that is responsible for focus, attention and decision making. A 2004 University of Iowa study found that damage to the frontal lobes of the brain can lead to poor judgment and emotional disturbances, while damage to the right medial prefrontal cortex of the brain tends to cause compulsive hoarding.
Some evidence based on brain lesion case studies also suggests that the anterior ventromedial prefrontal and cingulate cortices may be involved in abnormal hoarding behaviors, but sufferers of such injuries display less purposeful behavior than other individuals that compulsively hoard, thus making the implication of these brain structures unclear. Other neuropsychological factors that have been found to be associated with individuals exhibiting hoarding behaviors include slower and more variable reaction times, increased impulsivity, and decreased spatial attention.
Obsessive–compulsive disorder 
For many years hoarding has been listed as a symptom or a subtype of Obsessive Compulsive Disorder (OCD) and Obsessive Compulsive Personality Disorder (OCPD). The current DSM says that an OCD diagnosis should be considered when: 1. The hoarding is driven by fear of contamination or superstitious thoughts 2. The hoarding behavior is unwanted or highly distressing 3. The individual shows no interest in the hoarded items 4. Excessive acquisition is only present if there is a specific obsession with a certain item.
Compulsive hoarding does not seem to involve the same neurological mechanisms as more familiar forms of obsessive–compulsive disorder and does not respond to the same drugs, which target serotonin.. In compulsive hoarding the symptoms are presented in the normal stream of consciousness and as such, they are not perceived as repetitive or distressing like in OCD patients. More importantly, the statistics that indicate there is a prevalence of hoarding in 18-40 percent of patients with OCD, yet only five percent of compulsive hoarders experience symptoms of OCD. In another study, a sample of 217 patients diagnosed with significant hoarding, only 18% were diagnosed with OCD, as opposed to the 36% that were diagnosed with a major depressive disorder. There are significant differences and issues between the diagnostic features of compulsive hoarding and OCD which are being considered in a possible addition to the DSM-V of a new independent disorder such as compulsive hoarding. It is also said that there may be an overlap with a condition known as impulse control disorder (ICD), particularly when compulsive hoarding is linked to compulsive buying or acquisition behavior.
Recent findings suggest to differentiate between three types of hoarding, that is: pure hoarding, hoarding plus OCD (i.e., comorbid OCD), and OCD-based hoarding Given the aforementioned distinction, it was proposed to increase coverage of compulsive hoarding in the forthcoming Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-V), both by creating a distinct category for compulsive hoarding, provisionally named, Hoarding Disorder (either in the main manual under "obsessive-compulsive spectrum disorders" or in the appendix), and by including hoarding as a potential symptoms of OCD.
Book hoarding 
Bibliomania is a disorder involving the collecting or hoarding of books to the point where social relations or health are damaged. One of several psychological disorders associated with books (such as bibliophagy or bibliokleptomania), bibliomania is characterized by the collecting of books which have no use to the collector nor any great intrinsic value to a more conventional book collector. The purchase of multiple copies of the same book and edition and the accumulation of books beyond possible capacity of use or enjoyment are frequent symptoms of bibliomania.
One of the most famous bibliokleptomaniacs in American history, Stephen Blumberg, never felt that he was doing anything wrong. "Blumberg was trying to save a forgotten world from a system (the libraries) that neglected it."
Animal hoarding 
Animal hoarding involves keeping larger than usual numbers of animals as pets without having the ability to properly house or care for them, while at the same time denying this inability. Compulsive animal hoarding can be characterized as a symptom of a disorder rather than deliberate cruelty towards animals. Hoarders are deeply attached to their pets and find it extremely difficult to let them go. They typically cannot comprehend that they are harming their pets by failing to provide them with proper care. Hoarders tend to believe that they provide the right amount of care for their pets. The American Society for the Prevention of Cruelty to Animals provides a "Hoarding Prevention Team," which works with hoarders to help them attain a manageable and healthy number of pets. Along with other compulsive hoarding behaviors, it is linked in the DSM-IV to obsessive–compulsive disorder and obsessive–compulsive personality disorder. Alternatively, animal hoarding could be related to addiction, dementia, or even focal delusion.
Animal hoarders display symptoms of delusional disorder in that they have a "belief system out of touch with reality". Virtually all hoarders lack insight into the extent of deterioration in their habitation and the health of their animals, and tend not to recognize that anything is wrong. Delusional disorder is an effective model in that it offers an explanation of hoarders' apparent blindness to the realities of their situations.
Another model that has been suggested to explain animal hoarding is attachment disorder, which is primarily caused by poor parent-child relationships during childhood. As a result, those suffering from attachment disorder may turn to possessions, such as animals, to fill their need for a loving relationship. Interviews with animal hoarders have revealed that often, hoarders experienced domestic trauma in childhood, providing evidence for this model. Perhaps the strongest psychological model put forward to explain animal hoarding is obsessive–compulsive disorder (OCD).
Not only are there significant health risks associated with compulsive hoarding, but scientists are also trying to pinpoint how significant the interference is with occupational and social functioning in a hoarder's daily life. In a pool of compulsive hoarders, 42% found their behavior problematic to the 63% of their family and friends who saw the behavior as problematic. The findings suggest that individuals who hoard may exhibit impaired sensitivity to their own and others’ emotions, and conversely, relate the world around them by forming attachments to possessions rather than to people. Lower emotional intelligence among hoarding patients may also impact their ability to discard and organize their possessions. With such detrimental characteristics, comprehensive research has been performed to find a cure. Although this is ongoing research, most investigations have found that only a third of patients who hoard show an adequate response to these medications and therapeutic interventions. With the modifications to the DSM, insurance coverage for treatments will change as well as special education programs.
Psychopharmacological Interventions 
Obsessive-compulsive disorders are treated with various antidepressants: from the Tricyclic antidepressant family clomipramine (brand name Anafranil); and from the SSRI families paroxetine (Paxil), fluoxetine (Prozac), fluvoxamine (Luvox), sertraline (Zoloft) and citalopram (Celexa). With existing drug therapy, OCD symptoms can be controlled but not cured. Several of these compounds (including paroxetine, which has an FDA indication) have been tested successfully in conjunction with OCD hoarding.
Therapeutic Interventions 
Cognitive-behavioral therapy (CBT) is a commonly implemented therapeutic intervention for compulsive hoarding. As part of cognitive behavior therapy, the therapist may help the patient to:
- Discover why he or she is so compelled to hoard
- Learn to organize the possessions to decide what to discard.
- Develop the decision-making skills
- Declutter the home during in-home visits by a therapist or professional organizer
- Gain and perform relaxation skills
- Attend family and/or group therapy
- Be open to trying psychiatric hospitalization if the hoarding is serious.
- Have periodic visits and consultations to keep a healthy lifestyle.
This modality of treatment usually involves exposure and response prevention to situations that cause anxiety and cognitive restructuring of beliefs related to hoarding. Furthermore, research has also shown that certain CBT protocols have been more effective in treatment than others. CBT programs that specifically address the motivation of the sufferer, organization, acquiring new clutter, and removing current clutter from the home have shown promising results. This type of treatment typically involves in home work with a therapist combined with between-session homework, the completion of which is associated with better treatment outcomes. Research on internet-based CBT treatments for the disorder (where participants have access to educational resources, cognitive strategies, and chat groups) has also shown promising results both in terms of short- and long-term recovery.
Other therapeutic approaches that have been found to be helpful are:
- Motivational interviewing: originated in addiction therapy. This method is significantly helpful when incorporated in hoarding cases whereby insight is poor and ambivalence around change is marked;
- Harm reduction rather than symptom reduction: also borrowed from addiction therapy. The goal is to decrease the harmful implications of the behavior, rather than the hoarding behaviors;
- Groups therapy: reduce social isolation and social anxiety and are cost effective compared to one-on-one intervention.
Yet, individuals who present with hoarding behaviors are oftentimes described as having low motivation, and poor compliance levels, as being indecisive and procrastinators, which may frequently lead to premature termination (i.e., dropout) or low response to treatment. Therefore, it was suggested that future treatment approach and pharmacotherapy in particular, be directed to address the underlying mechanisms of cognitive impairments demonstrated by individuals with hoarding symptoms.
Mental health professionals frequently express frustration towards hoarding cases, mostly due to premature termination, and poor response to treatment. Respectively, patients are frequently described as indecisive, procrastinators, recalcitrant, and as having low or no motivation, which can explain why many interventions fail to accomplish significant results. In order to overcome this obstacle, some clinicians recommend accompanying individual therapy with home visits to assist the clinician: (a) getting a better insight into the hoarding severity and style, (b) devising a treatment plan that is more suitable to the particular case, and (c) desensitizing sufferers to visitors. Likewise, certain cases are assisted by professional organizers as well.
Case studies 
The following (edited) case study is taken from a published account of compulsive hoarding:
The client, D, lived with her two children, ages 11 and 14, and described her current hoarding behavior as a 'small problem that mushroomed' many years ago, along with corresponding marital difficulties. D reported that her father was a hoarder, and that she started saving when she was a child ... The volume of cluttered possessions took up approximately 70 percent of the living space in her house. With the exception of the bathroom, none of the rooms in the house could easily be used for their intended purpose. Both of the doors to the outside were blocked, so entry to the house was through the garage and the kitchen, where the table and chairs were covered with papers, newspapers, bills, books, half-consumed bags of chips, and her childrens' school papers dating back ten years.
The following case study is taken from a published account of compulsive hoarding:
A 79-year-old woman recently died in a fire at her Washington, D.C., row house when 'pack rat conditions' held back firefighters from reaching her in time. A couple of days later, 47 firefighters from four cities spent two hours fighting a fire in a Southern California home before they were able to bring it under control. There was floor-to-ceiling clutter that had made it almost impossible for them to come in the house.
In media and popular culture 
Hoarding in this context only entered widespread knowledge, media, and popular vocabulary after about 2000.
- Plyushkin is a fictional Russian hoarder in Nikolai Gogol's novel Dead Souls, published in 1842.
- Unknown Subject 522 (hoarder) in The Broken Window by Jeffery Deaver, published in 2008.
- Homer & Langley by E. L. Doctorow, published in 2009.
- In the 1989 Disney film, The Little Mermaid, the protagonist Ariel shows signs of compulsive hoarding of human objects.
- Packrat (2004) by Kris Montag
- Seven Dumpsters and a Corpse is a 2007 documentary film by Thomas Haemmerli.
- My Mother’s Garden (2008) by Cynthia Lester follows a 61-year-old woman’s daily life as a hoarder.
Hoarding has been featured in television programming on a number of occasions, often in the reality television genre. Notable examples from the US and UK include:
- Hoarders on A&E
- Clean House on the Style Network
- My Hoarder Mum and Me (BBC One), an observational documenary by Jasmine Harman
- Life Laundry on BBC Two
- Extreme Clutter on OWN
- Hoarding: Buried Alive on TLC, as well as various one-off programs on the subject (Help! I'm a Hoarder, Obsessive Compulsive Hoarder, and Truth be Told: I'm a Hoarder).
- Clean Sweep on TLC
- Stuffed: Food Hoarders was a one-off program on the Cooking Channel.
- The Hoarder Next Door (Channel 4)
- Parks and Recreation character Leslie Knope is shown to be a hoarder in her home.
Hoarding has also occurred as a theme for characters in fictional television shows. These have included Oscar the Grouch from children's show Sesame Street, whose outrageous hoarding behavior is a common theme; Ambrose Monk from comedy-drama Monk, and Eli Goldsworthy from teen drama Degrassi: The Next Generation. Hoarding has additionally served as the story basis for episodes of CSI: Crime Scene Investigation, South Park, Necessary Roughness, Bones, The Simpsons, Littlest Pet Shop (2012 TV series), 2 Broke Girls, SpongeBob SquarePants and House. The character of Parker Kensington Parker in the web series Pretty is revealed to be a hoarder in the series' third season.
See also 
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