Gender affirming hormonal treatment in Danish transgender persons: A nationwide register‐based study

BACKGROUND: Gender affirming hormonal treatment (GAHT) is a cornerstone in transgender care. National data are sparse regarding use of hormonal treatment by transgender persons. AIM: To assess use of GAHT in transgender persons. DESIGN: National register‐based cohort study in Danish transgender persons followed from 2000 until 2018. The main outcome measure was prescription and purchase of GAHT. Persons with ICD‐10 diagnosis code of “gender identity disorder” (CGI‐cohort) and persons with legal sex change but without diagnosis (CPR‐cohort) were included. In the CGI‐cohort, transgender women were defined by prescription of estrogen and/or cyproterone acetate and/or testosterone‐5‐alpha reductase inhibitors, and transgender men were defined by prescription of testosterone after study inclusion. Discontinuation of GAHT was defined as no purchase of GAHT ≥13 months or shift from feminizing to masculinizing hormone treatment, or vice versa. RESULTS: The cohort included 2789 transgender persons (n = 1717, CGI‐cohort and n = 1072, CPR‐cohort). The median age (interquartile range) at study inclusion was 26.1 (17.7) years for persons assigned male at birth (n = 1447) and 22.5 (10.5) years for persons assigned female at birth (n = 1342). In the CGI‐cohort, the event rate for GAHT in transgender women increased from 4.0 (95% confidence interval [CI]: [3.1; 5.2]) events per 100 person in year 2000–2005 to 20.6 (17.8; 23.7) between 2014 and 2018. In transgender men, the event rate of GAHT increased from 4.2 (2.8; 6.2) to 18.8 (16.4; 21.6). The rate of discontinuation of GAHT was 0.06 (95% CI 0.049; 0.071) per person year. CONCLUSIONS: The event rate of GAHT increased during 2000–2018. Our data suggested high adherence to GAHT.