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A latent profile analysis of age of onset in trichotillomania
Emily J Ricketts1, Ivar Snorrason, Katharina Kircanski
1Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, CA 90024-5055 USA.
Background:
Trichotillomania (TTM) onset may occur across the lifespan; however, adolescent onset is most frequently reported. Several studies 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 average 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 bodyfocused repetitive behaviors).
Conclusions:
Findings suggest the presence of at least 2 distinct TTM age-of-onset subgroups: an early-onset group with onset during adolescence, and a late-onset group with onset in middle adulthood. Future research is needed to further validate these subgroups and explore their clinical utility.
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