GnRHa therapy does not decrease BMD in children with congenital adrenal hyperplasia

Gonadotropin-releasing hormone analogue (GnRHa) therapy is not responsible for the reduction in bone mineral density (BMD) among children with congenital adrenal hyperplasia (CAH), reports a study.

The decrease in BMD over time and during the second and third decades of life could potentially be driven by chronic supraphysiologic glucocorticoids, according to the investigators.

This study included 61 patients with classic CAH due to 21-hydroxylase deficiency, of whom 20 were treated with GnRHa. Participants were followed with dual-energy X-ray absorptiometry (DXA) scans at puberty onset, attainment of adult height, and during early adulthood.

The investigators measured the whole body, lumbar spine, femoral neck, total hip, and distal radius BMD z-scores at adult height. They also evaluated longitudinal BMD and adult height.

Among the 20 patients who received GnRHa therapy, treatment lasted for an average of 4.5 years. No differences were noted in BMD between treated and untreated groups at adult height for all sites.

BMD z-scores for whole body (p=0.01), lumbar spine (p<0.0001), femoral neck (p=0.06), total hip (p=0.009), and distal radius (p=0.05) decreased in follow-up DXA during early adulthood.

Treatment with GnRHa resulted in improved height outcomes when compared with the predicted height at puberty onset after adjusting for midparental height (p=0.02). Additionally, patients in both groups attained comparable adult height.

“Children with CAH who experience early puberty benefit from GnRHa treatment as evidenced by the positive effect on height,” the investigators said.