title: Is trichotillomania a stereotypic movement disorder? An analysis of body-focused repetitive behaviors in people with hair-pulling.
abstract: BACKGROUND
  Stereotypic movement disorder (SMD) is characterized by nonfunctional repetitive movements, is typically diagnosed in people with intellectual disability, and by definition excludes people with trichotillomania (TTM). Nevertheless, hair-pulling may be one of a number of body-focused repetitive behaviors (BFRBs) that are seen in the general population. Comorbidity of symptoms might support the idea that they are indicative of an underlying stereotypic disorder, and we therefore explored their frequency in people with hair-pulling.
  
  
  METHODS
  Participants were recruited with the help of the Trichotillomania Learning Center, the largest advocacy group for people with hair-pulling. Participants completed a self-report survey on the Internet, which included questions about the presence of both hair-pulling and other BFRBs. Measures included the Massachusetts General Hospital Hairpulling Scale (MGH-HS), the Milwaukee Inventory for Subtypes of Trichotillomania-Adult Version (MIST-A), the Depression and Anxiety Stress Scale (DASS), and the Sheehan Disability Scale (SDS).
  
  
  RESULTS
  The majority of participants with hair-pulling (70%) report the presence of other BFRBs, most commonly skin-picking and nail-biting. There were particularly strong associations between the total number of BFRBs and increased scores on ratings of focused hair-pulling, depression, anxiety, stress, and functional impairment. Similar results were found in participants who met more rigorous criteria for trichotillomania.
  
  
  CONCLUSIONS
  This study is limited by its self-report nature, and by the lack of detailed information on the phenomenology of comorbid BFRBs. While further nosological research is needed, the high rates of these behaviors in people with hair-pulling, and their association with increased disability, is consistent with previous clinical observations, and supports the argument that trichotillomania can usefully be conceptualized as a stereotypic disorder. Speculatively, this argument may be especially valid in trichotillomania patients with more focused hair-pulling symptoms.
authors.affiliation: University of Cape Town, Rondebosch, South Africa. dan.stein@uct.ac.za
authors.forename: Dan J
authors.initials: DJ
authors.lastname: Stein
authors.forename: Christopher A
authors.initials: CA
authors.lastname: Flessner
authors.forename: Martin
authors.initials: M
authors.lastname: Franklin
authors.forename: Nancy J
authors.initials: NJ
authors.lastname: Keuthen
authors.forename: Christine
authors.initials: C
authors.lastname: Lochner
authors.forename: Douglas W
authors.initials: DW
authors.lastname: Woods
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001008:Anxiety Disorders / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology; D015897:Comorbidity; D003866:Depressive Disorder / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology; D004185:Disability Evaluation; D005260:Female; D006306:Health Surveys; D006801:Humans; D020407:Internet; D008297:Male; D008875:Middle Aged; D010555:Personality Inventory / Q000706:statistics & numerical data; D011594:Psychometrics; D016728:Self-Injurious Behavior / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology; D013239:Stereotyped Behavior; D019956:Stereotypic Movement Disorder / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology; D014256:Trichotillomania / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology; D055815:Young Adult