Time to Gender-Affirming Hormone Therapy Among US Military–Affiliated Adolescents and Young Adults

Importance Use of exogenous sex steroid hormones, when indicated, may improve outcomes in adolescents and young adults with gender incongruence. Little is known about factors associated with the time from diagnosis of gender dysphoria to initiation of gender-affirming hormone therapy. Identification of inequities in time to treatment may have clinical, policy, and research implications. Objective To evaluate factors associated with time to initiation of gender-affirming hormone therapy after a diagnosis of gender dysphoria in adolescents and young adults receiving care within the US Military Health System. Design, Setting, and Participants This retrospective cohort study used TRICARE Prime billing and pharmacy data contained in the Military Health System Data Repository. Patients aged 14 to 22 years, excluding service members and their spouses, who received a diagnosis of gender dysphoria between September 1, 2016, and December 31, 2021, were included. The data were analyzed between August 30 and October 12, 2023. Exposures Included patient characteristics were race and ethnicity, age group, first sex assigned in the medical record, and TRICARE Prime sponsor military rank and service at the time of diagnosis. Health care and contextual characteristics included the year of diagnosis and the primary system in which the patient received health care. Main Outcomes and Measures The primary outcome was the time between initial diagnosis of gender dysphoria to the first prescription for gender-affirming hormone medication within a 2-year period. A Poisson generalized additive model was used to evaluate this primary outcome. Adjusted probability estimates were calculated per specified reference categories. Results Of the 3066 patients included (median [IQR] age, 17 [15-19] years; 2259 with first assigned gender marker of female [74%]), an unadjusted survival model accounting for censoring indicated that 37% (95% CI, 35%-39%) initiated therapy by 2 years. Age-adjusted curves indicated that the proportion initiating therapy by 2 years increased by age category (aged 14-16 years, 25%; aged 17-18 years, 39%; aged 19-22 years, 55%). Incidence rate ratios (IRRs) and 2-year adjusted probabilities indicated that longer times to hormone initiation were experienced by adolescents aged 14 to 16 years (IRR, 0.36; 95% CI, 0.30-0.44) and 17 to 18 years (IRR, 0.66; 95% CI, 0.54-0.79) compared with young adults aged 19 to 22 years and Black compared with White adolescents (IRR, 0.73; 95% CI, 0.54-0.99). Senior officer compared with junior enlisted insurance sponsor rank (IRR, 1.93; 95% CI, 1.04-3.55) and civilian compared with military health care setting (IRR, 1.21; 95% CI, 1.02-1.43) was associated with shorter time to hormone initiation. Conclusions and Relevance In this cohort study, most adolescents and young adults with a diagnosis of gender dysphoria receiving health care through the US military did not initiate exogenous sex steroid hormone therapy within 2 years of diagnosis. Inequities in time to treatment indicate the need to identify and reduce barriers to care.