Hoarding Symptoms in Late Life Depression are Associated With Greater Executive Dysfunction and Disability and Poorer Response to Depression Treatment.

OBJECTIVES: Late life depression (LLD) and hoarding disorder (HD) are common in older adults and characterized by executive dysfunction and disability. We aimed to determine the frequency of co-occurring HD in LLD and examine hoarding severity as an additional contributor to executive dysfunction, disability, and response to psychotherapy for LLD. DESIGN: Cross-sectional. SETTING: Outpatient psychiatry program. PARTICIPANTS: Eighty-three community-dwelling adults ages 65-90 with LLD. INTERVENTION: Problem-solving therapy. MEASUREMENTS: Measures of executive function, disability, depression, and hoarding severity were completed at post-treatment. Pearson's chi-squared tests evaluated group differences in rates of cognitive impairment, disability, and depression treatment response between participants with HD (LLD+HD) and LLD only. Separate linear regressions assessed associations between hoarding severity and executive function, disability, and psychotherapy response. Covariates included age, education, gender, and depression severity. RESULTS: 30.1% (25/83) of LLD participants met HD criteria. Relative to LLD, LLD+HD participants demonstrated greater impairment rates on measures of executive function (Letter-Number-Sequencing, X2(1)=4.0, p = 0.045; Stroop-Interference, X2(1) = 4.8, p = 0.028). Greater hoarding severity was associated with poorer executive functioning performance (Letter-Number-Sequencing (t[70] = -2.1, ß = -0.05, p = 0.044), Digit-Span (t[71] = -2.4, ß = -0.07, p = 0.019), Letter-Fluency (t[ 71] = -2.8, ß = -0.24, p = 0.006)). Rates of disability were significantly higher for LLD+HD (88.0%) than LLD (62.3%), (X2[1] = 5.41, p = 0.020) and higher hoarding severity was related to greater disability (t[72] = 2.97, ß = 0.13, p = 0.004). Depression treatment response rates were significantly lower for LLD+HD (24.0%) compared to LLD (48.3%), X2(1) = 4.26, p = 0.039, and HD status predicted psychotherapy response, t(67) = -2.15, ß = -15.6, p = 0.035. CONCLUSIONS: We found 30.1% co-occurrence of HD in LLD, which was accompanied by greater executive dysfunction, disability, and poorer response to depression treatment. Results underscore the need for increased screening of hoarding behaviors in LLD and tailored interventions for this LLD+HD group.

Hard to let it go: repetitive negative thinking and hoarding in later life in Japan.

Objectives: Hoarding in older adults can have a detrimental effect on daily life. Repetitive negative thinking (RNT) could result in a greater avoidance of discarding and increased saving behaviors; yet, the unique role of RNT on hoarding in older adults remains understudied. This study aimed to investigate whether the intensity of RNT contributes to hoarding in older adults. Methods: Two hundred and sixty-four older adults in Japan (ages 65-86 years, 132 males and 132 females) participated in an online survey. Hierarchical regression analyses were conducted to examine whether RNT could significantly explain the variance of hoarding after controlling for age, sex, years of education, self-reported cognitive impairment, and depression. Results: As we expected, RNT was significantly associated with greater hoarding behaviors, such as excessive acquisition (ß = .27, p = .005) and difficulty in discarding (ß = .27, p = .003). On the other hand, reflection, repetitive thinking without negative emotional valence, was significantly associated with higher scores on clutter (ß = .36 p < .001). Conclusion: Our findings highlight the importance of addressing RNT in the prevention and treatment of hoarding symptoms among older adults, potentially leading to more effective interventions and improved outcomes in managing hoarding behaviors in this population.

When radical uncertainty is too much: Clinical aspects of Conviction Narrative Theory.

We propose extrapolating Conviction Narrative Theory (CNT) to clinical psychology and psychiatry. We demonstrate how CNT principles may benefit assessment, therapy, and possibly even modify public health views of neuropsychiatric disorders. Our commentary focuses on hoarding disorder as a model, elaborates on discrepancies in the scientific literature and suggests how the CNT may resolve them.

Do they really care? Specificity of social support issues in hoarding disorder and obsessive-compulsive disorder.

OBJECTIVES: Unmet interpersonal needs may play a role in excessive emotional attachments to objects for people with hoarding disorder (HD). Previous research indicates that social support (but not attachment difficulties) may be specific to HD. The study aimed to evaluate social networks and support in HD relative to clinical controls with obsessive-compulsive disorder (OCD) and healthy controls (HC). The secondary aim was to explore the extent of loneliness and thwarted belongingness. Potential mechanisms for deficits in social support were also considered. DESIGN: A cross-sectional between-groups design was used to compare scores on measures in those with HD (n = 37); OCD (n = 31); and HCs (n = 45). METHODS: Participants completed a structured clinical interview by telephone (to assign diagnostic categories) followed by online questionnaires. RESULTS: Whilst individuals with HD and OCD both report smaller social networks than HC, lower levels of perceived social support appear to be specific to HD. The HD group also showed higher levels of loneliness and thwarted belonging compared to OCD and HC. No differences were found between groups for perceived criticism or trauma. CONCLUSIONS: The results support previous findings of lower levels of self-reported social support within HD. Loneliness and thwarted belongingness also appear significantly elevated within HD compared with OCD and HC. Further research is required to explore the nature of felt support and belonging, direction of effect and to identify potential mechanisms. Clinical implications include advocating and promoting support systems (both personal supporters and professionals) for individuals with HD.

Changes in neural activity following a randomized trial of cognitive behavioral therapy for hoarding disorder.

OBJECTIVE: Cognitive behavioral therapy (CBT) is efficacious for hoarding disorder (HD), though results are modest. HD patients show an increase in activity in the dorsal anterior cingulate cortex (dACC) when making decisions. The aim of this study is to determine whether CBT's benefits follow improvements in dACC dysfunction or abnormalities previously identified in other brain regions. METHOD: In this randomized clinical trial of 64 treatment-seeking HD patients, patients received group CBT, delivered weekly for 16 weeks, versus wait list. Functional magnetic resonance imaging was used to examine neural activity during simulated decisions about whether to acquire and discard objects. RESULTS: During acquiring decisions, activity decreased in several regions, including right dorsolateral prefrontal, right anterior intraparietal area, both right and left medial intraparietal areas, left and right amygdala, and left accumbens. During discarding decisions, activity decreased in right and left dorsolateral prefrontal, right and left rostral cingulate, left anterior ventral insular cortex, and right medial intraparietal areas. None of the a priori brain parcels of interest significantly mediated symptom reduction. Moderation effects were found for left rostral cingulate, right and left caudal cingulate, and left medial intraparietal parcels. CONCLUSIONS: Therapeutic benefits of CBT for HD do not appear to be mediated by changes in dACC activation. However, pretreatment dACC activation predicts outcome. Findings suggest the need to re-evaluate emerging neurobiological models of HD and our understanding of how CBT affects the brain in HD, and perhaps shift focuses to new neural target discovery and target engagement trials. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Situational, emotional, and individual dispositions to weight gain in people with hoarding problems.

OBJECTIVES: Individuals with hoarding disorder are more likely to be overweight or obese than the general population for unknown reasons. METHODS: One hundred and twenty-nine individuals (Hoarding Group: n = 63; Control Group: n = 66) completed self-report measures and were offered snacks in a tidy and a cluttered environment in a counterbalanced order. Groups were based on the self-reporting of high or low hoarding symptoms. RESULTS: The hoarding group reported being less able to use their kitchen and prepare food at home and experiencing more impulsivity, distress intolerance and problematic eating beliefs than did the control group. The hoarding group consumed more cookies in the tidy room, whereas the control group consumed more cookies in the cluttered room. Greater impulsivity, distress intolerance and problematic body and eating beliefs were related to greater cookie consumption for the hoarding group. CONCLUSIONS: Early interventions that help individuals to tolerate distress and to engage in goal-directed behaviour regardless of their emotional state may have benefits for both hoarding and eating behaviour. We encourage future researchers to examine this hypothesis.

Psychological mechanism of acceptance and commitment therapy and rational emotive behavior therapy for treating hoarding: Evidence from randomized controlled trials.

Hoarding is a common problem behavior worldwide and is detrimental to the physical and mental health of individuals and groups. Currently, effective interventions for hoarding are cognitive-behavioral therapies, but their post-intervention efficacy is questionable, and the available research does not examine the mediating variables of the effects of interventions on clinical outcomes. Moreover, current research on hoarding has focused on Western countries. Therefore, there is a need to investigate the efficacy of other forms of cognitive behavioral therapy on hoarding as well as other psychological outcomes related to hoarding and mediating variables that contribute to its effectiveness in different cultural contexts. One hundred thirty-nine college students with higher hoarding behaviors were randomly divided into three groups: 45 in the Acceptance and Commitment Therapy (ACT) group, 47 in the Rational Emotive Behavior Therapy (REBT) group, and 47 in the control group. They completed the Saving Inventory-Revised (SI-R), Obsessive-Compulsive Symptom Scale (OCSS), Difficulties in Emotion Regulation Scale (DERS), Experiences in Close Relationships Inventory-Attachment Anxiety Subscale (ECR), Depression Anxiety Stress Scales (DASS-21), Acceptance and Action Questionnaire II (AAQ-II), and Cognitive Fusion Questionnaire (CFQ) before and immediately after the intervention. The results showed that ACT and REBT improved individuals' psychological flexibility, cognitive fusion, acquisition-difficulty discarding, clutter, negative affect (anxiety, depression, stress), attachment anxiety, obsessive-compulsive disorder, and difficulty in emotion regulation compared to the control group. In addition, ACT was more effective than REBT in improving psychological flexibility and reducing hoarding, cognitive fusion, depression, stress, and obsessive-compulsive disorder; there were no significant differences between the two in anxiety and emotion regulation difficulties. Furthermore, psychological flexibility is a mediator of the effect of ACT and REBT on some behavioral and psychological outcomes (hoarding, negative affect, attachment anxiety). Limitations were discussed.

Hoarding Disorder: The Current Evidence in Conceptualization, Intervention, and Evaluation.

Hoarding disorder is characterized by difficulty parting with possessions due to strong urges to save the items, leading to the excessive accumulation of items. High clutter levels result in varied personal, social, and legal consequences. Specialized treatments, including individual, virtual, and group cognitive and behavioral therapies, community-based interventions, and peer support approaches have shown preliminary effectiveness. Animal, attachment, and neurobiological models are expanding our understanding of the etiological bases of the disorder. Specialized populations such as children, older adults, and involuntary patients are highlighted as requiring special consideration for intervention and risk mitigation. Directions for future research are identified.

The generational impact of household clutter.

OBJECTIVES: Hoarding disorder can create long-term problems for adult children of individuals with hoarding symptoms; however, the extent of the psychosocial consequences of growing up in a cluttered household are not yet fully understood. This study investigated the extent to which generational clutter (i.e., parent/caregiver and grandparent) influenced individuals' self-reported hoarding severity and psychiatric and psychosocial functioning. METHODS: A total of 1306 adults completed an online survey that included measures of hoarding, anxiety, depression, companionship and emotional support. A subsample (n = 198) reported on parent and grandparent household clutter, as well as family impact from hoarding. We used correlations, t-tests, linear and hierarchical regressions and mediation analyses to investigate whether hoarding symptoms were predicted by parent or grandparent hoarding. RESULTS: Parent clutter level significantly predicted participant hoarding symptoms. For participants who reported having caregivers with elevated clutter, self-reported psychosocial functioning was lower overall. Self-reported behaviour modification due to family hoarding symptoms (accommodation) was a significant predictor of participant hoarding symptoms. CONCLUSIONS: Parent clutter and family accommodation behaviours may be a risk factor for future clutter in adult children. Further comparisons between parents and children are needed to determine whether this association increases children's risk for future hoarding symptoms.

Cognitive impairment in hoarding disorder: a systematic review.

OBJECTIVE: In the present study, we aimed to perform a systematic review evaluating the cognitive performance of patients with hoarding disorder (HD) compared with controls. We hypothesized that HD patients would present greater cognitive impairment than controls. METHODS: A systematic search of the literature using the electronic databases MEDLINE, SCOPUS, and LILACS was conducted on May 2020, with no date limit. The search terms were "hoarding disorder," "cognition," "neuropsychology," "cognitive impairment," and "cognitive deficit." We included original studies assessing cognitive functioning in patients with HD. RESULTS: We retrieved 197 studies initially. Of those, 22 studies were included in the present study. We evaluated 1757 patients who were 41 to 72 years old. All selected studies comprised case-control studies and presented fair quality. Contrary to our hypothesis, HD patients showed impairment only in categorization skills in comparison with controls, particularly at confidence to complete categorization tasks. Regarding attention, episodic memory, working memory, information-processing speed, planning, decision-making, inhibitory control, mental flexibility, language, and visuospatial ability, HD patients did not show impairment when compared with controls. There is a paucity of studies on social cognition in HD patients, although they may show deficits. The impact of emotion in cognition is also understudied in HD patients. CONCLUSION: Except for categorization skills, the cognitive performance in HD patients does not seem to be impaired when compared with that in controls. Further work is needed to explore social cognition and the impact of emotion in cognitive performance in HD patients.

Anosognosia in hoarding disorder is predicted by alterations in cognitive and inhibitory control.

Insight impairment contributes significantly to morbidity in psychiatric disorders. The neurologic concept of anosognosia, reflecting deficits in metacognitive awareness of illness, is increasingly understood as relevant to psychopathology, but has been little explored in psychiatric disorders other than schizophrenia. We explored anosognosia as an aspect of insight impairment in n = 71 individuals with DSM-5 hoarding disorder. We used a standardized clutter severity measure to assess whether individuals with hoarding disorder underreport home clutter levels relative to independent examiners. We then explored whether underreporting, as a proxy for anosognosia, is predicted by clinical or neurocognitive behavioral measures. We found that individuals with hoarding disorder underreport their clutter, and that underreporting is predicted by objective severity of clutter. In an n = 53 subset of participants, we found that underreporting is predicted by altered performance on tests of cognitive control and inhibition, specifically Go/No-Go and Stroop tests. The relation of underreporting to objective clutter, the cardinal symptom of hoarding disorder, suggests that anosognosia may reflect core pathophysiology of the disorder. The neurocognitive predictors of clutter underreporting suggest that anosognosia in hoarding disorder shares a neural basis with metacognitive awareness deficits in other neuropsychiatric disorders and that executive anosognosia may be a transdiagnostic manifestation of psychopathology.

Redefining object attachment: Development and validation of a new scale.

Background and aims: Object attachment is the emotional bond or connection that we have with possessions. Although thought to be ubiquitous, when excessive, object attachment is presumed to contribute to compulsive buying and hoarding problems. Unfortunately, our understanding of this relationship has been limited by the constraints of existing object attachment measures. In this paper, we developed and validated a new self-report questionnaire, called the Object Attachment Security Measure (OASM). Methods: We developed an item pool based on previous measures and consultation with 24 experts in the field. After piloting, we administered this measure to a large sample (Final N = 365), along with self-report measures of hoarding, compulsive buying, and previous object attachment measures. Results: We found that the OASM distinguished between secure and insecure object attachment. Both subscales showed excellent internal consistency and test-retest reliability over a two-week period. Additionally, they demonstrated excellent convergent and divergent validity, and criterion validity with measures of hoarding and compulsive buying symptoms. We also found that insecure, but not secure object attachment, was uniquely related to hoarding and compulsive buying symptomology. Discussion and conclusion: Our findings extend theoretical models, highlighting the role of insecure object attachment. Future research in both clinical and consumer behaviour fields should utilise the OASM, as reducing insecure object attachment and potentially encouraging secure object attachment could decrease maladaptive possession use and increase sustainable consumption.

What is underneath all that stuff? A Q-methodological exploration of profiles of beliefs and vulnerabilities in hoarding disorder.

BACKGROUND: Hoarding disorder (HD) can be understood through the cognitive behavioural model in the context of vulnerability factors (for example, personality traits, co-morbidities, traumatic life events) and beliefs about possessions (for example, identity, emotional attachment, memory, utility). Less is known about the strength of these hypothesised beliefs, or how they interact within the hoarding population, with researchers suggesting that specifying beliefs would improve treatment outcomes. AIM: The current study explored beliefs in HD, utilising Q-methodology to explore both categories of beliefs and the interactions between these. Moreover, Q-methodology allowed for comparison of the individuals endorsing specific categories of beliefs. METHOD: A comprehensive list of beliefs about possessions was developed. Thirty-two adults with clinically significant levels of HD completed a Q-sort task, alongside measures of proposed vulnerabilities, including co-morbidity, trauma and attachment style. RESULTS: Q-factor analysis produced four profiles consisting of groups of participants who endorsed the same beliefs and had shared characteristics: (1) 'Expression of identity', (2) 'Responsibility and morality', (3) 'Stability and predictability', and (4) 'Objects as emotional and meaningful beings'. DISCUSSION: The profiles were distinguished by different categories of beliefs and co-morbid symptoms, suggesting that more targeted assessment tools and interventions would be beneficial to account for this heterogeneity within the clinical population. In particular, beliefs about identity and self-concept formed the largest profile, and beliefs about stability and predictability introduce a novel category of beliefs.

Council tenancies and hoarding behaviours: A study with a large social landlord in England.

Hoarding behaviours are highly stigmatised and often hidden. People with problematic hoarding behaviours have a higher rate of mental health and other healthcare and social services utilisation. Hoarding is a community health problem, one factor being housing insecurity. Hoarding behaviours represent significant burden to housing providers, impact the community and dealing with it involves multiple community agencies. This study with a city council in England with a large housing stock (over 14,000 properties) in summer 2021 sought to understand the nature, circumstances and extent that hoarding presents. We developed a reporting system and conducted 11 interviews with housing officers in which they described a case to explain their involvement. Our report details the nature of 38 people who hoard: 47% had a known disability or vulnerability, 34% presented a fire and environmental risk, 87% lived alone and 60% were resident in flats. Our qualitative themes are: Working with others, Balancing an enforcement approach, Feeling conflicted, Complex needs of people who hoard and Staff needs. The cases described by the housing officers are combined into six case studies and illustrate the complex, multi-agency circumstances around decision making and risk stratification. Our findings point to housing officers as frontline professionals dealing with a public health and social care issue which is often the manifestation of complex life histories and mental health conditions. We suggest a greater focus on risk stratification and a more holistic approach to hoarding cases to effectively deal with this most complex of community health and social care issues.

The roles of intolerance of uncertainty, anxiety sensitivity and distress tolerance in hoarding disorder compared with OCD and healthy controls.

BACKGROUND: It is suggested that the different psychological vulnerability factors of intolerance of uncertainty (IU), anxiety sensitivity (AS) and distress tolerance (DT) may be in important in hoarding disorder (HD). However, the extent to which these factors are specific to HD compared with other disorders remains unclear. AIMS: The current study aimed to investigate differences in IU, AS and DT in three groups: HD (n=66), obsessive compulsive disorder (OCD; n=59) and healthy controls (HCs; n=63). METHOD: Participants completed an online battery of standardised self-report measures to establish the independent variable of group membership (HD, OCD and HC) and the dependent variables (IU, AS and DT). RESULTS: A MANOVA analysis indicated statistically significant differences in IU, AS and DT between the clinical groups and HCs. Follow-up analyses showed no statistically significant differences between the HD and OCD group for any of the three constructs. The results remained the same when examining the effects of co-morbid HD and OCD. An unexpected finding was the trend for IU, AS and DT to be more severe when HD and OCD were co-morbid. CONCLUSIONS: The evidence suggests the absence of a specific relationship between IU, AS or DT in HD and instead is consistent with existing research which suggests that these psychological vulnerability factors are transdiagnostic constructs across anxiety disorders. The implications of the findings are discussed.

A critical review of cognitive behavioural therapy for hoarding disorder: How can we improve outcomes?

Psychological treatment for hoarding problems has historically been associated with poor outcomes. When treated as a subgroup of obsessive-compulsive disorder, individuals with hoarding beliefs were less likely to respond to treatment than individuals exhibiting other obsessive-compulsive beliefs and behaviours. When treated as its own disorder using cognitive behavioural therapy, individuals report approximately 25% improvement in symptoms on average. However, less than a third of people experience clinically meaningful change. Further, changes in functioning and quality of life are not routinely assessed. In this paper, we review the current conceptualization and treatment of hoarding problems to shed light on how treatment for hoarding disorder may be improved. Utilizing a harm reduction approach before administering treatment may be important to ensure the safety of individuals. Research should test whether treatment outcomes improve by including strategies that enhance a client's interpersonal functioning and ability to regulate emotions (i.e., based on dialectal behaviour therapy and mentalization-based treatments), especially while discarding and organizing belongings. We should also use modern learning theory to improve the delivery of exposure activities.

Prevalence and correlates of hoarding behavior and hoarding disorder in children and adolescents.

Although hoarding symptoms are reported to begin in childhood and adolescence, the true prevalence of the disorder in this age group is unknown. This study aims to estimate the prevalence of hoarding disorder (HD) in children and adolescents. The present study was planned as a two-stage epidemiological research. In the first stage, the Children's Saving Inventory (CSI) and informed consent forms were delivered to a group of students' parents. In the second stage, one-on-one psychiatric interviews with a physician were planned with the families and children who had hoarding behavior (HB), as described by their parents. The DSM-5-based HD interview and the Development and Well-Being Assessment (DAWBA) diagnostic tool were used to detect prevalence of HD and comorbid psychiatric disorders. A total of 3249 children were included in the study, and 318 children and their parents were evaluated in the second stage. As a result of the second assessment, 32 out of 318 children met the HD diagnostic criteria. The estimated prevalence of HD was 0.98% (95% CI 0.7-1.4). Hoarding disorder was found more frequently in females (F/M = 3/1). After a logistic regression analysis, variables such as female sex and the presence of any psychopathology were identified as independent correlates of HD. More than half (56.2%) of the children diagnosed as having HD also had a comorbid psychiatric disorder. In the present study, the two-stage evaluation method was used in a large pediatric sample to determine the estimated prevalence of HD, as well as the factors associated with the disorder and comorbid psychiatric disorders.

Investigating associations between hoarding symptoms and affective and cognitive empathy.

OBJECTIVES: Hoarding is associated with poor interpersonal functioning, such as social isolation and difficulties in forming relationships, but the reasons for these social problems are not well understood. Previous studies have identified empathy as an important precursor to social functioning, particularly for clinical disorders characterized by social deficits. The aim of the current study was therefore to investigate associations between measures of cognitive and emotional empathy and hoarding symptoms. METHOD: A total of 278 participants recruited via MTurk completed online self-report questionnaires on hoarding, empathy (including cognitive and affective components), and depression. All participants subsequently completed The Awareness of Social Inference Test-Short version (TASIT-S), a behavioural measure of theory of mind, a concept used interchangeably with cognitive empathy. RESULTS: Hoarding symptoms were associated with greater self-reported emotional empathy, specifically emotional contagion, and less self-reported cognitive empathy. Emotional empathy predicted hoarding even after controlling for depression symptoms. Hoarding symptoms were also associated with poorer performance on the TASIT-S with respect to both emotion recognition and theory of mind, with theory of mind remaining a unique predictor of hoarding symptoms after controlling for depression. Participants who reported clinically significant hoarding symptoms were impaired in emotion recognition and theory of mind according to TASIT-S norms. CONCLUSIONS: Hoarding symptoms are associated with increased emotional contagion and decreased cognitive empathy. Empathy may be an avenue for understanding and treating interpersonal difficulties in hoarding disorder. PRACTITIONER POINTS: As hoarding increased, self-reported emotional contagion increased As hoarding increased, self-reported and behavioural cognitive empathy decreased Self-reported emotional empathy and behavioural cognitive empathy predicted hoarding even after controlling for depression Empathy may be an avenue for understanding social difficulties in hoarding disorder.

The developmental origins of hoarding disorder in adolescence: a longitudinal clinical interview study following an epidemiological survey.

Hoarding disorder (HD) is hypothesized to originate in childhood/adolescence but little is known about the presentation of hoarding symptoms in youth and their natural history. In this longitudinal study, we tracked and conducted in-depth psychiatric interviews with twins who participated in an epidemiological survey and screened positive on a measure of hoarding symptoms at age 15. Twins screening positive for clinically significant hoarding symptoms at age 15 (n = 42), their co-twins (n = 33), a group of screen negative twins (n = 49), and their parents underwent a clinical assessment a median of 3 years after the initial screening. The assessment included psychiatric screening, hoarding symptoms and cognitions, in-home or photographic assessment of clutter levels, parental accommodation and familial burden. None of the participants had significant levels of clutter at follow-up and thus did not meet strict criteria for HD. However, twins meeting partial criteria (i.e., DSM-5 criteria A and B) for HD (n = 28) had more psychiatric disorders and scored significantly higher on all measures of hoarding symptoms including researcher-rated levels of clutter in their homes, compared to twins who did not meet partial criteria for HD (n = 46). As currently defined in DSM-5, HD may be rare in young people. A non-negligible proportion of young people who were screen positive on hoarding symptoms at age 15 had substantial hoarding symptoms and other psychopathology at follow-up. Whether and how many of these individuals will develop full-blown HD is unknown but the results offer unique insights about the probable origins of HD in adolescence.