Androgenetic alopecia incidence in transgender and gender diverse populations: A retrospective comparative cohort study.

BACKGROUND:Androgenetic alopecia (AGA) is a significant challenge for many transgender and gender diverse (TGD) patients, but the rate of AGA among TGD patients receiving gender-affirming hormone therapy (GAHT) compared to cisgender patients has not yet been studied on a large scale. OBJECTIVE:We examined the incidence of AGA among TGD patients receiving GAHT compared to cisgender patients. METHODS:Retrospective cohort study using electronic health records from 37,826 patients seen at Fenway Health between August 1, 2014, and August 1, 2020. Crude and adjusted incidence rate ratios (aIRR) for AGA were calculated using Poisson regression. RESULTS:TGD patients receiving masculinizing GAHT had aIRR 2.50, 95% CI 1.71-3.65 and 1.30, 95% CI 0.91-1.86 compared to cisgender women and cisgender men, respectively. The rate of AGA for TGD patients receiving feminizing GAHT was not significantly different compared to cisgender men but was significantly increased compared to cisgender women (aIRR 1.91, 95% CI 1.25-2.92). LIMITATIONS:Inability to determine causation and limited generalizability. CONCLUSION:TGD patients receiving masculinizing GAHT have 2.5 times the rate of AGA compared to cisgender women, whereas TGD patients on feminizing GAHT did not have a significantly increased rate of AGA compared to cisgender men.