Chronic hair-pulling: phenomenology-based subtypes.

Distinct subtypes of trichotillomania (TTM)/chronic hair-pulling may exist. The aim of this study was to extend an earlier analysis by our group to a larger sample of patients with chronic hair-pulling, and to assess the validity and clinical utility of several putative subtypes. Eighty patients with various putative hair-pulling subtypes were compared on sociodemographic and clinical variables. Gender and disability due to pulling accounted for a number of important differences; for example, females more commonly had earlier age of onset of pulling, less comorbidity, and more disability than males. Also, those who met DSM-IV criteria B and C of TTM appeared to have a more disabling course of illness than those who did not. These data appear to support a dimensional rather than a categorical approach to subtyping. Future work, incorporating further investigation of the role of gender and psychobiological and treatment outcomes, is needed before definitive conclusions about hair-pulling subtypes can be drawn. Copyright 2009 Elsevier Ltd. All rights reserved.