Stereotyped movement disorder in ICD-11

Non-suicidal self-injury in trichotillomania and skin picking disorder

BACKGROUND

Trichotillomania and skin picking disorder have been characterized as body-focused repetitive behavior (BFRB) disorders (i.e., repetitive self-grooming behaviors that involve biting, pulling, picking, or scraping one's own hair, skin, lips, cheeks, or nails). Trichotillomania and skin picking disorder have also historically been classified, by some, as types of compulsive self-injury as they involve repetitive hair pulling and skin picking, respectively. The question of the relationship of these disorders to more conventional forms of self-injury such as cutting or self-burning remains incompletely investigated. The objective of this study was to examine the relationship of these two disorders with non-suicidal self-injury (NSSI).

METHODS

Adults with trichotillomania (n = 93) and skin picking (n = 105) or both (n = 82) were recruited from the general population using advertisements and online support groups and completed an online survey. Participants completed self-report instruments to characterize clinical profiles and associated characteristics. In addition, each participant completed a mental health history questionnaire.

RESULTS

Of the 280 adults with BFRB disorders, 141 (50.1%) reported a history of self-injury independent of hair pulling and skin picking. Participants with a history of self-injury reported significantly worse pulling and picking symptoms (p < .001) and were significantly more likely to have co-occurring alcohol problems (p < .001), borderline personality disorder (p < .001), buying disorder (p < .001), gambling disorder (p < .001), compulsive sex behavior (p < 001), and binge eating disorder (p = .041).

CONCLUSIONS

NSSI appears common in trichotillomania and skin picking disorder and may be part of a larger constellation of behaviors associated with impulse control or reward-related dysfunction.