The hoarding dimension of OCD: Psychological comorbidity and the five-factor personality model

Abstract

Although hoarding has been associated with several psychological disorders, it is most frequently linked to obsessive–compulsive disorder (OCD). The present study assessed hoarding obsessions and compulsions in 204 individuals with OCD, and evaluated how hoarding was related to obsessive–compulsive symptom severity, psychological comorbidity, and personality as measured by the five-factor model. Results indicated that hoarding in OCD is a dimensional variable that is positively associated with dysphoria, total number of lifetime Axis I disorders, and lifetime histories of bipolar I, PTSD, and body dysmorphic disorder. Hoarding was negatively correlated with the NEO-Personality Inventory-Revised (NEO-PI-R) factor of Conscientiousness and positively associated with the NEO-PI-R factor of Neuroticism. When all personality and psychopathology variables were entered into a regression equation, dysphoria, bipolar II disorder, Conscientiousness, age, and Extraversion emerged as significant predictors of hoarding severity. Recommendations are made for clinicians and for future research.

Introduction

Obsessive–compulsive disorder (OCD), once thought to be a rare anxiety disorder, is now believed to affect between 1% and 3% of the general population (e.g., Weissmann et al., 1994). While certain clinical symptoms are common to all persons with OCD, other features vary among individuals. Hoarding obsessions and compulsions are examples of such variable OCD characteristics that have only recently been explored empirically.

Hoarding may be defined as the acquisition of and failure to discard apparently useless possessions (Frost & Gross, 1993). In some extreme cases, hoarding may pose dangerous emotional and physical risks to individuals, as well as to entire communities. Extensive clutter increases fire hazards and the threat of personal injury or death, and hoarding of food and animals may elevate risk of illness or contamination. Although some data suggest a familial pattern (Frost & Gross, 1993; Samuels et al., 2002) and chromosomal regions linked to hoarding obsessions and compulsions have been found in a Tourette's Disorder sibling sample (Zhang et al., 2002), the causes of hoarding remain unknown and are likely multimodal.

Hoarding is a symptom of several psychological disorders, and hoarding behaviors exist in a wide range of conditions including dementia (Hwang, Tsai, Yang, Liu, & Lirng, 1998), focal lesions of the mesial frontal cortex identified by MRI (Anderson, Damasio, & Damasio, 2005), depression (Shafran & Tallis, 1996), and anorexia nervosa (Frankenburg, 1984). However, hoarding is most commonly associated with OCD, where symptoms affect between 18% and 42% of OCD clients (Hanna, 1995; Rasmussen & Eisen, 1992; Samuels et al., 2002).

Relatively little is known about the relationships among hoarding, psychopathology, and personality in OCD-affected individuals, although several studies have found that hoarding is related to treatment response, outcome, and comorbidity patterns. Hoarding has been associated with less improvement following exposure with response prevention (Mataix-Cols, Marks, Greist, Kobak, & Baer, 2002), cognitive-behavior therapy (Abramowitz, Franklin, Schwartz, & Furr, 2003; Black et al., 1998; Saxena et al., 2002), psychosocial rehabilitation (Saxena et al., 2002), and psychopharmacological treatment (Black et al., 1998; Mataix-Cols, Rauch, Manzo, Jenike, & Baer, 1999; Saxena et al., 2002).

In studies of psychopathology, Frost, Steketee, Williams, and Warren (2000) reported that OCD hoarding clients scored higher on scales of anxiety and depression and evidenced more dependent and schizotypal personality disorder symptoms than OCD clients who did not hoard. Samuels et al. (2002) found that OCD hoarders displayed a higher prevalence of Axis I disorders (including social phobia, brief depression, and hypomania), Axis II disorders (including obsessive–compulsive, borderline, histrionic, and narcissistic personality disorders), and pathological grooming behaviors (including trichotillomania, nail biting, and skin picking). Steketee, Frost, and Kyrios (2003) found that compulsive hoarders (70% diagnosed with OCD) scored significantly higher than individuals with OCD (without hoarding) and controls on measures of depression and anxiety. Fontenelle, Mendlowicz, Soares, and Versiani (2004) reported higher rates of comorbid bipolar II disorder and eating disorders among OCD hoarders. Hartl, Duffany, Allen, Steketee, and Frost (2005) found that compulsive hoarders (32% with a prior diagnosis of OCD) reported a larger number of types of trauma, greater frequency of traumas experienced, and higher scores on inattention and hyperactivity scales. Frost, Krause, and Steketee (1996) found that compulsive hoarders scored higher on a measure of general psychopathology, and Frost and Gross (1993) reported that hoarders seek psychotherapy more often than nonhoarders. More research, with larger sample sizes, is needed to establish whether patterns of comorbidity are related to the hoarding dimension.

No study to date has assessed the relationship between hoarding and normal personality as measured by the Big Five (McCrae & Costa, 1999). The Five-Factor Model (FFM) proposes that personality is comprised of Neuroticism, Extraversion, Openness to experience, Agreeableness, and Conscientiousness. Some investigations have assessed five-factor personality traits among individuals with OCD, although none have compared differences based on the presence of hoarding. Samuels et al. (2000) found that individuals with OCD had significantly higher levels of Neuroticism when compared to controls. OCD-affected individuals also scored significantly lower than controls on Extraversion and higher on Agreeableness, but their scores were similar to the population means for those factors. One study comparing depressed individuals to those with OCD found that the latter scored higher on Extraversion and Agreeableness, and lower on Neuroticism, once depression was controlled (Rector, Hood, Richter, & Bagby, 2002). Finally, Bienvenu et al. (2004) found that individuals with OCD scored high on both Neuroticism and Openness compared to controls.

Of particular interest in OCD samples is Neuroticism, which refers to high degrees of emotional instability (Costa & McCrae, 1992). Elevated levels of Neuroticism are linked with a predisposition to psychological distress (Costa & Widiger, 1994) and increased psychopathology (Widiger & Trull, 1992). Low levels of Extraversion, or preference for interpersonal interaction, activity, and ability to experience joy (Costa & Widiger, 1994) have also been associated with the presence of psychological disorders (Widiger & Trull, 1992) and may be related to hoarding in OCD. Finally, Conscientiousness may be negatively correlated with hoarding, as Conscientiousness is related to being highly orderly (Costa & McCrae, 1992) and measures the degree to which a person is organized, persistent, and goal-directed (Costa & Widiger, 1994).

The purpose of the present study was to assess the extent of hoarding in a large sample of individuals with OCD, and to determine whether the hoarding dimension was related to obsessive–compulsive symptom severity, psychological comorbidity, and five-factor personality traits. Consistent with the available literature on comorbidity, the first prediction was that hoarding would be associated with a higher prevalence of social phobia, major depression, and bipolar disorders. The second prediction stated that hoarding would exhibit a positive relationship with Neuroticism and negative relationships with Extraversion and Conscientiousness. In line with previous research, the third prediction was that hoarding would be associated with dysphoria and obsessive–compulsive symptom severity.