Leuprolide Acetate and QTc Interval in Gender-Diverse Youth

Background: Puberty suppression is a standard of care for gender-affirming therapy in gender-diverse youth. Leuprolide acetate is a gonadotropin-releasing hormone agonist (GnRHa) commonly used for pubertal suppression. There are concerns that GnRHa agents prolong the rate-corrected QT interval (QTc) when used as androgen deprivation therapy in management of prostate cancer; however, there is a paucity of literature regarding the effect of leuprolide acetate on QTc intervals in gender-diverse youth.Aim: To determine the proportion of gender-diverse youth with QTc prolongation on leuprolide acetate therapy.Methods: A retrospective chart review of gender-diverse youth initiated on leuprolide acetate between July 1, 2018 and December 31, 2019 was conducted at a tertiary care pediatric hospital in Alberta, Canada. Youth aged 9-18 years were included if a 12-lead electrocardiogram was completed after initiating leuprolide acetate. The proportion of adolescents with clinically significant QTc prolongation was assessed, defined as QTc >460 milliseconds (ms).Results: Thirty-three pubertal youth were included. The cohort had a mean age of 13.7 years (standard deviation [SD] 2.1) and 69.7% identified as male (assigned female at birth). The mean post-leuprolide acetate QTc was 415 ms (SD 27, range 372-455). Twenty-two (66.7%) of youth were prescribed concomitant medications, including QTc-prolonging medications in 15.2%. None of the 33 youth on leuprolide acetate had QTc prolongation. Only 24.2% patients had a borderline QTc (QTc 440-460 ms).Conclusion: No gender-diverse youth on leuprolide acetate demonstrated clinically significant QTc prolongation.