Acne incidence in transgender adolescents: A multi-center cohort study

Summary: Abstract Body: Endogenous puberty, puberty blockers, and gender-affirming hormone therapy may influence acne development in transgender adolescents, but epidemiologic data are scant. This study aimed to examine acne incidence in a validated cohort of transgender adolescents enrolled in Kaiser Permanente Northern and Southern California, Georgia, and Mid-Atlantic States. Transgender adolescents were followed from first documented transgender status (index date) to incident acne (≥1 ICD code) in 1/2006–6/2024. Up to 10 cisgender male (CM) and 10 cisgender female (CF) adolescents matched to each transgender adolescent by age, race/ethnicity, enrollment year, and site were followed from the index date. Incidence rates were compared using negative binomial regression. Subgroup analysis was performed for transmasculine (TM) adolescents receiving testosterone. 5,638 TM adolescents (mean age (SD) 13.6 (2.2) years) and 1,746 TF adolescents (mean (SD) age 12.9 (3.7) years) were matched with 58,718 CM and 56,397 CF adolescents. Mean (SD) follow-up times in TM and TF adolescents were 4.4 (2.7) and 4.9 (3.2) years. Incident acne rates were higher in TM adolescents than CM adolescents (Incidence rate ratio [IRR]=1.1, 95% CI 1.0–1.3; Incidence rates [IR]=43.5 vs 39.8) but similar in CF adolescents (IRR=1.0, 0.9–1.1; IR=44.0 vs 44.4); and similar in TF adolescents than CM adolescents (IRR=1.1, 0.9–1.3; IR=31.8 vs 31.3) and CF adolescents (IRR=0.9, 0.7–1.0; IR=31.6 vs 35.3). 1,979 transmasculine adolescents initiated testosterone at a mean (SD) age of 17.6 (2.3) and had higher incident acne rates than CM adolescents (IRR=2.0, 1.6–2.4; IR=53.5 vs 37.3) and CF adolescents (IRR=1.7, 1.4–2.1; IR=53.7 vs 40.9). This study relied on clinician-diagnosed cases and may not generalize to uninsured patients. Future research should examine how hormone therapy regimens and timing influence acne in transgender adolescents. Clinicians should address acne management in TM adolescents receiving testosterone. Courtney A. Smith¹, Oumaima Kaabi², Ketki Joshi¹, Vin Tangpricha³, Michael Goodman², Howa Yeung¹ 1. Dermatology, Emory University, Atlanta, GA, United States. 2. Emory University Department of Epidemiology, Atlanta, GA, United States. 3. Endocrinology, Emory University, Atlanta, GA, United States. Minoritized Populations and Health Disparities Research