ORIGINAL ARTICLE Clinical Characteristics of Pediatric Trichotillomania: Comparisons with Obsessive–Compulsive and Tic Disorders Michelle Rozenman 1 • Tara S. Peris 1 • Araceli Gonzalez 2 • John Piacentini 1 Ó Springer Science+Business Media New York 2015 Abstract This study compared youth ages 5–17 years with a primary diagnosis of trichotillomania (TTM, n = 30) to those with primary OCD (n = 30) and tic disorder (n = 29) on demographic characteristics, internalizing, and external- izing symptoms. Findings suggest that youth with primary TTM score more comparably to youth with tics than those with OCD on internalizing and externalizing symptom mea- sures. Compared to the OCD group, youth in the TTM group reported lower levels of anxiety and depression. Parents of youth in the TTM group also reported fewer internalizing, externalizing, attention, and thought problems than those in the OCD group. Youth with TTM did not significantly differ from those with primary Tic disorders on any measure. Findings suggest that pediatric TTM may be more similar to pediatric tic disorders than pediatric OCD on anxiety, de- pression, and global internalizing and externalizing problems. Keywords Trichotillomania Á OCD Á Tic disorder Á Impulse control disorder Á Child Á Adolescent Introduction Pediatric trichotillomania (TTM) is a chronic and highly impairing psychiatric condition in which affected youth pull hair from one or more areas on their body, resulting in hair loss or thinning. Also known as hair-pulling disorder [1], TTM has been found to occur in up to 3.4 % of adults [2] and 1 % of youth [3]. Children and adolescents suf- fering from TTM often report an inability to control their pulling behavior, as well as embarrassment and shame due to resultant hair loss [4, 5]. Given this degree of distress and impairment, and the fact that secrecy regarding the condition is common, current estimates of pediatric TTM are thought to underestimate the condition’s true preva- lence. Across the developmental spectrum, individuals with TTM experience significant physical, emotional, and social impairment, as well as high rates of co-occurring anxiety and depression [6–8]. Despite the significant burden of disease, knowledge regarding pediatric TTM remains relatively sparse. Both pediatric and adult TTM studies have found the condition to occur more frequently in females than males (up to 80 % female samples; [3, 9–12], although the gender ratio may be more comparable in early childhood [13, 14]. Average onset age for TTM is proposed to be between 9 and 13 years, with a bimodal distribution of either childhood- or adolescent-onset [5]. The adolescent-onset subtype has been associated with greater severity, more co-occurring psychopathology, and worse treatment outcome [15, 16]. A substantial proportion of TTM sufferers report co- morbid psychiatric diagnoses across the lifespan, including anxiety disorders (10–60 %; [12, 17–19], OCD (5–13 % [2, 20]) and tic disorders (6–9 %; [6, 20]), and ADHD and other externalizing disorders (10–40 %; [3, 19]). These rates are substantially increased when considering co-oc- curring psychiatric symptoms that do not necessarily meet for a full diagnosis. Even when they do not meet criteria for comorbid diagnoses, children and adolescents with TTM report clinically elevated levels of internalizing symptoms (between 40 and 45 %; [12, 21]). & Michelle Rozenman mrozenman@mednet.ucla.edu 1 Division of Child and Adolescent Psychiatry, UCLA Semel Institute for Neuroscience and Human Behavior, 760 Westwood Plaza, 67-455, Los Angeles, CA 90095, USA 2 Department of Psychology, California State University Long Beach, Long Beach, CA, USA 123 Child Psychiatry Hum Dev DOI 10.1007/s10578-015-0550-2