Partitioning the etiology of hoarding and obsessive–compulsive symptoms

Abstract

Background Until recently, hoarding was considered an obsessive-compulsive symptom (OCS). However, current evidence suggests that these two phenotypes may be clinically, and perhaps etiologically, distinct. Both hoarding and OCS have a genetic etiology, but the degree of unique and shared genetic contributions to these phenotypes is not well studied. Methods Prevalence rates were assessed for hoarding and OCS in a sample of adult twin pairs (N = 7,906 twins) and their family members from the Netherlands Twin Register (total sample = 15,914). Using Mplus, genetic analyses using liability threshold models were conducted for both phenotypes, for their comorbidity, and for specific hoarding symptoms (cluttering, discarding, and acquiring). Results 6.7% of the total sample met criteria for clinically significant hoarding; endorsement of all three hoarding symptoms was over 85%. Men had slightly higher rates than women. 5.7% met criteria for clinically significant OCS; rates were similar in males and females. Genetic factors accounted for 36% of the variance for hoarding and 40% of the variance for OCS. The genetic correlation between hoarding and OCS was 0.10. There was no evidence of sex-specific genetic contributions for hoarding or OCS. There was evidence for a genetic contribution to all hoarding symptom subtypes. Only cluttering showed evidence of a contribution from shared environment. Conclusions OCS and hoarding are common in this population-based sample, are similar to previously reported prevalence rates, and show significant heritability. Genetic factors contributed to the comorbidity of both traits, although the genetic correlation between them was low.

The relationship between tics, OC, ADHD and autism symptoms: A cross- disorder symptom analysis in Gilles de la Tourette syndrome patients and family-members

“…This inattention/hoarding dimension is in line with recent studies suggesting that hoarding is a symptom dimension separate from the OCD phenotype (Pertusa et al, 2008; Pertusa et al, 2010; Mathews et al, 2014). Moreover, in DSM 5, hoarding is placed as a separate disorder in the group of OCD spectrum disorders (Mataix-Cols and Pertusa, 2012).…”

Age-Specific Prevalence of Hoarding and Obsessive Compulsive Disorder: A Population-Based Study

“…Some studies have found increased rates of hoarding among males (5, 12, 13, 31), while others report higher rates among females (18), or no sex differences (7, 11). This variability may be partly the result of whether the study sample was clinical or epidemiological in nature, as females are more likely to present for clinical care.…”

“…In 2013, the Diagnostic and Statistical Manual of Mental Health Disorders, 5th edition (DSM-5) named hoarding disorder (HD) as a distinct clinical syndrome within the OCD and related disorders category(4). This change was informed by over a decade of accelerated research efforts examining pathological hoarding behaviors, indicating that hoarding behavior is only present in about 20% of individuals with clinically significant OC symptoms, and that reversely around 83% of individuals with clinically significant hoarding symptoms do not present with clinically significant OC symptoms(5–9). These data suggest that individuals with OCD and hoarding may represent only a fraction of the total population suffering from HD (1).…”

“…Expert consensus reports population prevalence of HD between 2% and 6% (4, 11–13). The wide range of published prevalence estimates (1.5–14%) (5, 14–22) and the typically lower reported prevalence in studies of children and adolescents (18, 23) underscore the need for additional work on the course of HD with aging. Previous retrospective studies suggest that hoarding symptoms begin during childhood and adolescence (10, 24), and increase in severity throughout life.…”

Comparison of brain activation patterns during executive function tasks in hoarding disorder and non-hoarding OCD

“…While HD often co-occurs with obsessive-compulsive disorder (OCD) (Saxena, 2007; Steketee and Frost, 2003), HD and OCD appear to have separate etiologies and outcomes, as evidenced by disparate genetic contributions, ages of onset, comorbidities, and treatment responses (Mathews et al, 2014; Miguel et al, 2005; Saxena, 2008; Steketee and Frost, 2003; Tolin et al, 2014). However, hoarding was until recently classified as a subtype of OCD, and therefore most studies of the pathophysiology of hoarding, including neuroimaging studies, have focused on individuals with primary OCD and co-occurring hoarding symptoms (Alvarenga et al, 2012; Gilbert et al, 2008; Harrison et al, 2013; Mataix-Cols et al, 2004; Valente et al, 2005).…”