Abstract
Transgender youth may initiate GnRH agonists (GnRHa) to suppress puberty, a critical period for bone-mass accrual. Low bone mineral density (BMD) has been reported in late-pubertal transgender girls before gender-affirming therapy, but little is known about BMD in early-pubertal transgender youth. To describe BMD in early-pubertal transgender youth. Cross-sectional analysis of the prospective, observational, longitudinal Trans Youth Care Study cohort. Four multidisciplinary academic pediatric gender centers in the United States. Early-pubertal transgender youth initiating GnRHa. Areal and volumetric BMD Z-scores. Designated males at birth (DMAB) had below-average BMD Z-scores when compared with male reference standards, and designated females at birth (DFAB) had below-average BMD Z-scores when compared with female reference standards except at hip sites. At least 1 BMD Z-score was < -2 in 30% of dmab and 13% of dfab. youth with low bmd scored lower on the physical activity questionnaire for older children than youth with normal bmd, 2.32 ± 0.71 vs. 2.76 ± 0.61 (p =" 0.01)." there were no significant deficiencies in vitamin d, but dietary calcium intake was suboptimal in all youth. in early-pubertal transgender youth, bmd was lower than reference standards for sex designated at birth. this lower bmd may be explained, in part, by suboptimal calcium intake and decreased physical activity-potential targets for intervention. our results suggest a potential need for assessment of bmd in prepubertal gender-diverse youth and continued monitoring of bmd throughout the pubertal period of gender-affirming therapy. transgender youth may initiate gnrh agonists (gnrha) to suppress puberty, a critical period for bone-mass accrual. low bone mineral density (bmd) has been reported in late-pubertal transgender girls before gender-affirming therapy, but little is known about bmd in early-pubertal transgender youth. to describe bmd in early-pubertal transgender youth. cross-sectional analysis of the prospective, observational, longitudinal trans youth care study cohort. four multidisciplinary academic pediatric gender centers in the united states. early-pubertal transgender youth initiating gnrha. areal and volumetric bmd z-scores. designated males at birth (dmab) had below-average bmd z-scores when compared with male reference standards, and designated females at birth (dfab) had below-average bmd z-scores when compared with female reference standards except at hip sites. at least 1 bmd z-score was >< -2 in 30% of dmab and 13% of dfab. youth with low bmd scored lower on the physical activity questionnaire for older children than youth with normal bmd, 2.32 ± 0.71 vs. 2.76 ± 0.61 (p =" 0.01)." there were no significant deficiencies in vitamin d, but dietary calcium intake was suboptimal in all youth. in early-pubertal transgender youth, bmd was lower than reference standards for sex designated at birth. this lower bmd may be explained, in part, by suboptimal calcium intake and decreased physical activity-potential targets for intervention. our results suggest a potential need for assessment of bmd in prepubertal gender-diverse youth and continued monitoring of bmd throughout the pubertal period of gender-affirming therapy.>
