Hoarding Disorder

Hoarding Disorder (HD) is an obsessive-compulsive and related disorder in the DSM-5-TR characterised by persistent difficulty discarding or parting with possessions, regardless of their actual value. The difficulty stems from a perceived need to save items and distress at the thought of getting rid of them. Accumulation of possessions fills and clutters active living areas to the point that their intended use becomes impossible. References: DSM-5-TR, StatPearls (NCBI Bookshelf).

Hoarding Disorder (HD) is an obsessive-compulsive and related disorder in the DSM-5-TR characterised by persistent difficulty discarding or parting with possessions, regardless of their actual value. The difficulty stems from a perceived need to save items and distress at the thought of getting rid of them. Accumulation of possessions fills and clutters active living areas to the point that their intended use becomes impossible. HD was first recognised as a standalone diagnosis in DSM-5 (2013), having previously been classified as a feature of OCD or OCPD. It carries ICD-11 code 6B24. Every major public health department contends with hoarding-related hazards, including fire risk, structural damage, pest infestation, and blocked egress. HD differs from collecting: collectors organise and display items, while people with HD accumulate disorganised clutter that causes distress and impairs daily functioning. This information is for psychoeducation only.

The core symptom triad: (1) persistent difficulty discarding possessions regardless of monetary value, (2) strong urges to save items and marked distress when forced to discard, and (3) accumulation that fills living spaces and prevents normal use (e.g., cannot cook in the kitchen, sleep in the bed, sit on the sofa). Common categories of hoarded items include newspapers, clothing, containers, junk mail, books, and craft supplies. Many individuals also engage in excessive acquisition — compulsive buying, collecting free items, or stealing. Insight varies widely. Some recognise the behaviour as problematic; others see nothing wrong with their cluttered home. Emotional attachments to objects are intense: items may represent safety, identity, potential usefulness, or memory. Individuals often report feeling overwhelmed by the volume of possessions and unable to decide what to keep or discard. Avoidance of discarding decisions is typical. Social embarrassment leads many to refuse visitors, isolating themselves.

Genetic: first-degree relatives of people with HD have a 3-fold increased risk. Twin studies estimate heritability at ~50%. A family history of hoarding behaviour is reported in 50-85% of cases. Temperament: indecisiveness, perfectionism, procrastination, and avoidant coping style are strongly associated. Many individuals score high on measures of emotional attachment to possessions and anthropomorphising of objects. Life events: stressful or traumatic events (bereavement, divorce, eviction) often precipitate or worsen hoarding. Childhood material deprivation and growing up in cluttered homes are risk factors. Demographics: prevalence increases with age, peaking after age 55. Both sexes are affected, though clinical samples skew ~60% female. Living alone is a risk factor, partly because cohabitants constrain clutter accumulation.

Comorbidity: co-occurring psychiatric conditions are the norm rather than exception (see Section 5).

The neurocognitive model of HD proposes deficits in four domains: information processing (difficulty categorising and organising), decision-making (extreme indecisiveness about possessions), emotional regulation (strong positive attachment to objects plus strong negative emotions about discarding), and behavioural avoidance (procrastination, avoiding sorting tasks). Neuroimaging shows abnormal activation in the anterior cingulate cortex (ACC) and insula during discarding decisions — hyperactivation when discarding personal items, hypoactivation when discarding others' items. The ACC is involved in error monitoring and conflict detection; its dysfunction may underlie the paralysing indecision. Genetic factors overlap partially with OCD but are largely distinct. The serotonin system is implicated but less strongly than in OCD. Dopaminergic reward pathways may drive excessive acquisition, as acquiring new items activates ventral striatal reward circuits. Attachment theory models suggest insecure attachment styles lead to substituting objects for human connection.

Community prevalence: 2-6% of adults meet diagnostic criteria. Point prevalence in the general population is approximately 2.5%. Mean age of onset: mid-30s, but most individuals do not seek treatment until their 50s. Symptoms typically begin mildly in adolescence and worsen progressively. HD is 3 times more common in adults over 55 than in younger adults. Gender: roughly equal in community samples, though women predominate in treatment-seeking populations (~60%). Comorbidity rates: major depressive disorder 50-75%, generalised anxiety disorder ~25%, OCD ~20%, ADHD 20-30%, social anxiety disorder ~20%. Animal hoarding — keeping large numbers of animals without adequate care — affects an estimated 700-2,000 cases per year in the United States. The economic burden includes municipal cleanup costs (averaging $5,000-$50,000 per case), fire department responses, adult protective services involvement, and housing code enforcement.

Functional MRI studies show that individuals with HD exhibit abnormal activity in the ACC, medial prefrontal cortex, and insula when making decisions about personal possessions. Specifically, the ACC shows hypoactivation when processing items belonging to others (reduced error-monitoring engagement) and hyperactivation when processing personal possessions (excessive conflict signalling). The insula, which processes interoceptive and emotional signals, shows heightened activation, potentially reflecting the visceral distress experienced during discarding. Structural MRI reveals reduced grey matter volume in the dorsal ACC and posterior cingulate cortex compared to healthy controls. Executive function testing shows deficits in sustained attention, categorisation, and set-shifting. Working memory impairments are common, particularly visuospatial working memory. These cognitive deficits likely contribute to difficulty organising possessions and making efficient discard decisions. Serotonin transporter availability may be altered, though findings are less consistent than in OCD.

Neurobiology in Simple Terms Hoarding involves brain circuits for decision-making, emotional attachment, and organising information. The anterior cingulate cortex (ACC)—which flags conflict and helps us choose—shows unusual activity: when deciding about their own possessions, people with hoarding disorder experience intense distress and "error" signals, as if discarding were dangerous. The insula, which processes internal feelings about objects, may amplify emotional attachment to items. Executive functions (attention, categorising, shifting between tasks) can be weaker, making it hard to sort and prioritise. Acquiring new items can activate reward circuits (dopamine), similar to compulsive buying. Serotonin may play a role. Hoarding is not laziness—it reflects how the brain processes possessions and decisions. Specialised CBT for hoarding helps people gradually change these patterns.

Assessment requires: (1) Detailed history of hoarding behaviours — age of onset, types of items, acquisition patterns, living conditions, and functional impact. (2) Ideally a home visit or home photographs, as office-based assessment often underestimates severity. (3) Standardised measures: the Saving Inventory-Revised (SI-R, 23 items measuring acquisition, difficulty discarding, and clutter), the Clutter Image Rating (CIR, photographic scale 1-9 for each room), and the Hoarding Rating Scale (HRS-SR). (4) Assessment of insight using the Brown Assessment of Beliefs Scale or the overvalued ideas scale. (5) Screening for comorbidities: depression (PHQ-9), anxiety (GAD-7), OCD (Y-BOCS), ADHD. (6) Physical examination focused on consequences of hoarding: malnutrition, injuries from falls over clutter, respiratory problems from dust/mould exposure, skin infections, and untreated medical conditions due to healthcare avoidance.

DSM-5-TR Criteria: (A) Persistent difficulty discarding or parting with possessions, regardless of actual value. (B) Difficulty is due to perceived need to save items and distress associated with discarding. (C) Accumulation results in clutter that fills active living areas and substantially compromises their intended use. If living areas are uncluttered, it is only because of third-party interventions. (D) Causes clinically significant distress or impairment in social, occupational, or other areas of functioning (including maintaining a safe environment). (E) Not attributable to another medical condition (e.g., brain injury, cerebrovascular disease). (F) Not better explained by another mental disorder (e.g., obsessions in OCD, decreased energy in MDD, delusions in psychosis, cognitive deficits in major NCD). Specifiers: "With excessive acquisition" — if difficulty discarding is accompanied by excessive collecting, buying, or stealing. Insight specifier: "With good or fair insight," "With poor insight," or "With absent insight/delusional beliefs." ICD-11 code: 6B24.

Standardised instruments: SI-R (Saving Inventory-Revised) provides subscales for clutter, difficulty discarding, and excessive acquisition. CIR (Clutter Image Rating) uses photographs of rooms at varying clutter levels; the patient selects the image most closely matching each room. Scores of 4+ indicate clinically significant clutter. The HRS-SR (Hoarding Rating Scale-Self Report) is a brief 5-item screener.

The Activities of Daily Living in Hoarding (ADL-H) assesses functional impairment specifically related to clutter. Home visits, when feasible, provide the most accurate assessment; alternatively, patient-taken photographs or video tours serve as proxies. Neuropsychological testing may reveal executive function deficits in categorisation, decision-making speed, and sustained attention. Rule out hoarding secondary to neurodegenerative conditions (frontotemporal dementia, Alzheimer's), brain injury, or Prader-Willi syndrome (food hoarding). Assess safety: fire risk, fall hazards, pest infestation, blocked exits, structural integrity, and child/elder protective concerns.

OCD: in OCD, hoarding stems from specific obsessions (contamination fear preventing discarding, symmetry obsessions requiring specific arrangements). In HD, the motivation is emotional attachment, perceived utility, or aesthetic value. OCD-related hoarding responds better to standard OCD treatment. OCPD: excessive orderliness and perfectionism differ from HD's disorganised clutter. MDD: psychomotor retardation and apathy can cause accumulation, but the person does not resist discarding and lacks emotional attachment to items. Psychotic disorders: delusions about possessions differ from HD's overvalued ideas. Neurodegenerative disorders (frontotemporal dementia, Alzheimer's): late-onset hoarding with progressive cognitive decline suggests NCD rather than primary HD. Prader-Willi syndrome: food hoarding driven by hyperphagia. ASD: restricted interests may lead to collecting, but the motivation and pattern differ. Normal collecting: organised, displayed, within budget and space limits, not distressing.

Treatment of Hoarding Disorder is challenging and requires specialised approaches. Psychotherapy: CBT adapted for Hoarding Disorder is the primary treatment. Components include psychoeducation about hoarding, motivational interviewing to address ambivalence about change, cognitive restructuring targeting beliefs about possessions (emotional attachment, responsibility, need for control), graded exposure to sorting, discarding, and non-acquiring, organisational skills training, and relapse prevention. Home visits are often a critical component, as office-based therapy alone may not generalise to the home environment. Group CBT and peer-led support groups can supplement individual therapy. Treatment typically requires 20-26 sessions, longer than standard CBT protocols. The Buried in Treasures (BiT) workshop is a 15-20 session group-based self-help programme that uses the Steketee and Frost treatment manual and has shown moderate effect sizes (d = 0.5-0.8). Pharmacotherapy: SSRIs (paroxetine, venlafaxine) have limited evidence and are generally less effective for hoarding than for other OCD-spectrum conditions. Medication may be more useful for comorbid depression or anxiety. Stimulant medication may help when ADHD comorbidity contributes to disorganisation and inattention. Practical Support: Professional organisers, harm reduction approaches (addressing safety hazards without requiring complete decluttering), and community-based support services may be helpful, especially when insight is poor or motivation is limited. Task forces combining mental health, social services, and public health agencies are increasingly used for severe cases.

Peer support specialists with lived experience of hoarding can improve engagement and retention.

HD follows a chronic, progressive course without treatment. Symptoms rarely remit spontaneously. Average duration of illness before first treatment contact exceeds 20 years. With CBT-HD, approximately 60-70% of patients show clinically meaningful improvement (defined as >=30% reduction on SI-R). However, post-treatment clutter scores rarely reach non-clinical levels; residual symptoms are common. Treatment dropout rates are high (25-40%), often related to poor insight, low motivation, or comorbid depression. Poor prognostic indicators include older age at treatment entry, lower insight, greater clutter severity, and comorbid personality disorder. Better outcomes associate with earlier treatment, higher motivation, good therapeutic alliance, and inclusion of home-based sessions. Relapse prevention and booster sessions improve maintenance of gains. Without treatment, hoarding typically worsens decade by decade, accelerating after age 50 when reduced mobility and accumulating possessions compound each other.

Fire: cluttered homes have dramatically increased fire risk. Fire departments report that hoarding contributes to fires that are harder to suppress and more deadly — blocked exits prevent escape, and stacked combustible materials accelerate spread. Falls and injuries: navigating cluttered spaces causes falls, fractures, and entrapment under collapsed piles (in severe cases, fatal crush injuries have been documented). Health hazards: accumulated dust, mould, pest infestations (rodents, cockroaches), and decaying food create respiratory problems and infections. Animal hoarding leads to animal neglect, unsanitary conditions, and zoonotic disease transmission. Social consequences: eviction, legal proceedings, family estrangement, and social isolation. Relationship conflict is nearly universal. Financial consequences: compulsive acquisition drains finances; cleanup and remediation costs are substantial. Child and elder protective services may intervene when dependants live in unsafe conditions. Suicide risk: HD carries elevated suicide risk, partly mediated by comorbid depression, social isolation, and the despair of enforced cleanouts.

No validated primary prevention exists. Early identification matters: hoarding behaviour typically begins in adolescence, and early intervention before clutter becomes severe is more effective. Healthcare providers, social workers, code enforcement officers, and fire departments should screen for hoarding. Patient education points: HD is a recognised medical condition, not laziness or choice; it responds to specialised treatment (CBT-HD); forced cleanouts without therapy have near-100% relapse rates and cause significant psychological harm; gradual self-directed decluttering with professional support produces lasting change; excessive acquisition must be addressed alongside discarding difficulty; comorbid conditions (depression, ADHD, anxiety) need treatment too. Family education: avoid arguments about possessions, do not discard items without permission, support professional treatment, set boundaries around shared living spaces, and contact the International OCD Foundation's hoarding resources.

Hoarding was described in literature centuries before psychiatric classification. Dante's Inferno (1320) portrays hoarders and wasters in the Fourth Circle of Hell. The Collyer brothers of New York City died in 1947 amid 140 tons of accumulated possessions, becoming the most famous historical case. Hoarding was long considered a subtype of OCD or a feature of OCPD. Frost and Hartl published the first cognitive-behavioural model in 1996. Research in the 2000s demonstrated that hoarding had distinct neurobiology, genetics, and treatment response from OCD. Field trials for DSM-5 confirmed that hoarding warranted its own diagnostic category. DSM-5 (2013) introduced Hoarding Disorder as a new standalone diagnosis under Obsessive-Compulsive and Related Disorders. ICD-11 (2022) followed suit with code 6B24. The recognition of HD as a separate disorder spurred development of specialised treatment manuals (Steketee & Frost, 2007, 2014) and community task forces in major US cities.

Hoarding has gained public visibility through reality television (Hoarders, Hoarding: Buried Alive), which raised awareness but also sensationalised the condition. Many people with HD feel stigmatised and fear being labelled "dirty" or "crazy." Cultural factors influence what is hoarded and attitudes toward discarding. In societies emphasising thrift and resourcefulness, hoarding behaviour may be normalised longer. Older adults who lived through economic depression or war-time rationing may have stronger save-everything mentalities. Squalor and self-neglect are not inherent to HD — many individuals with HD maintain personal hygiene and non-cluttered workspaces while their homes are impassable. Municipal hoarding task forces now operate in over 100 US cities, coordinating responses among fire departments, social services, animal control, housing authorities, and mental health providers. The economic cost of hoarding-related interventions (cleanup, legal proceedings, housing remediation) runs into hundreds of millions of dollars annually in the US alone.

Active research areas include: (1) Neuroimaging — clarifying the role of ACC and insula dysfunction in discarding decisions; resting-state fMRI studies examining default mode network connectivity. (2) Genetics — genome-wide association studies have identified candidate loci on chromosomes 14q and 3q; the ZNF385D gene variant has been associated with compulsive hoarding. (3) Digital interventions — smartphone apps for tracking acquisition and discarding; virtual reality exposure therapy for practising discarding in simulated environments. (4) Treatment augmentation — combining CBT-HD with transcranial magnetic stimulation (TMS) targeting the ACC; adding methylphenidate for ADHD comorbidity. (5) Animal hoarding — understanding its overlap with HD and animal welfare implications. (6) Geriatric hoarding — adapted interventions for older adults with mobility limitations and cognitive decline. (7) Harm reduction models — evaluating safety-focused approaches for individuals who refuse decluttering.

APA. (2022). Diagnostic and Statistical Manual of Mental Disorders (5th ed., text rev.; DSM-5-TR). APA Publishing. Sadock BJ, Sadock VA, Ruiz P. (Eds.). (2024). Kaplan & Sadock's Comprehensive Textbook of Psychiatry (11th ed.). Wolters Kluwer. StatPearls [Internet]. Hoarding Disorder. NCBI Bookshelf. StatPearls Publishing. Steketee G, Frost RO. (2014). Treatment for Hoarding Disorder: Therapist Guide (2nd ed.). Oxford University Press. WHO. (2022). ICD-11 for Mortality and Morbidity Statistics. Geneva: World Health Organization.

StatPearls Hoarding Disorder: https://www.ncbi.nlm.nih.gov/books/NBK519704/ International OCD Foundation Hoarding: https://hoarding.iocdf.org NIMH: https://www.nimh.nih.gov WHO ICD-11 code 6B24: https://icd.who.int Buried in Treasures Workshop: https://www.oxfordclinicalpsych.com Crisis: 988 (US Suicide & Crisis Lifeline); Text HOME to 741741 (Crisis Text Line) Note: Educational only. Not a substitute for professional care.