A latent profile analysis of age of onset in trichotillomania

background: Trichotillomania (TTM) onset may occur across the life-span; however, adolescent onset is most frequently reported. Several stud-ies have explored clinical differences between TTM age-of-onset groups with mixed results. We investigated empirically defined age-of-onset groups in adults with TTM, and clinical differences between groups. methods: Participants included 1,604 adult respondents to an internet survey who endorsed DSM-IV-TR TTM criteria. Latent profile analysis was performed to identify TTM age-of-onset subgroups, which were then compared on demographic and clinical features. results: The most optimal model was a 2-class solution comprised of a large group with average TTM onset during adolescence (n = 1,539; 95.9% of the sample; mean age of onset = 12.4) and a small group with aver- A ge onset in middle adulthood (n = 65; 4.1% of the sample; mean age of onset = 35.6). The late-onset group differed from the early-onset group on several clinical variables (eg, less likely to report co-occurring body-focused repetitive behaviors). conclusions: Findings suggest the presence of at least 2 distinct TTM age-of-onset subgroups: An early-onset group with onset during adoles-cence, and a late-onset group with onset in middle adulthood. Future research is needed to further validate these subgroups and explore their clinical utility.