Impact of non-weight-dependent low-dose somatropin on bone accrual in childhood-onset GH deficient in the transition: an 18-month randomized controlled trial

Abstract

Objective Discontinuation of growth hormone therapy (rhGH) upon completion of linear growth may adversely affect bone mineral density (BMD) and bone mineral content (BMC) in adolescents with childhood-onset GH deficiency (CO-GHD) and predispose them to osteoporosis. In the present study, we analyzed the impact of non-weight-based low-dose somatropin withdrawal on bone accrual during this transition among CO-DGH patients who had been treated since childhood. Methods Lumbar spine (LS) and whole-body (WB) BMD and BMC were measured at baseline and after 18 months in 54 adolescents (age: 16.8 ±1.6 years). They were retested and reclassified as GH sufficient (GS, n= 28) and GH insufficient. The last group were later randomized to use rhGH (GH+; n= 15) or no treatment (GH-, n= 11) in this single-center open-label study. The average dose of rhGH was 0.5 ± 0.18 mg/day. Results When comparing the 3 groups, the GH group had a lower percentage change in LS BMD than the GS group (0.53 % ± 5.9 vs. 4.42 % ± 4.1, respectively, p < 0.04). However, in the analysis of the GH+ and GH- subgroups, the LS BMC percentage change was higher in the GH+ group (11.02% ± 10.12 vs. 2.05 % ± 10.31, respectively, p< 0.04). Conclusions Non-weight-based low-dose somatropin withdrawal for 18 months limits bone accrual in LS of CO-DGH in transition. More studies on this therapeutic regimen are necessary to assess the long-term impact on peak bone mass in these younger populations.