Effects of recombinant human growth hormone (GH) replacement therapy on bone metabolism in children with GH deficiency

Abstract

To study the changes of bone turnover markers and bone mass in children with growth hormone (GH) deficiency before and after recombinant human GH replacement therapy. Serum levels of bone turnover markers (OC, BAP and ICTP), IGF1 and distal radius bone mass (SOS SDS) of 37 cases with complete growth hormone deficiency (CGHD), 31 partial growth hormone deficiency (PGHD) and 31 age- and sex-matched healthy controls were measured. Twenty-nine patients received rhGH replacement therapy at dose of 0.03 mg/kg. day and the above parameters were measured every 3 or 6 months after treatment. Compared with the control, baseline serum levels of BAP, ICTP and IGF1 in CGHD group were significantly decreased (P<0.05), so was IGF1 in PGHD group (P<0.05). Significantly positive correlation was found between IGF1 and ICTP (r=0.32, P=0.01) in CGHD group. There was no significant difference between GHD group and the control in other biochemical parameters. All bone turnover markers and IGF1 increased significantly in both CGHD and PGHD children after rhGH replacement therapy for 3 months (P<0.05). ICTP and IGF1 were increasing with the prolonged rhGH replacement therapy. A tendency of increase in distal radius SOS SDS was also seen after rhGH-treatment, though not statistically significant (P>0.05). Compared with the control, bone turnover markers BAP and ICTP are lower in children with CGHD, with lower IGF1 but unchanged bone mass in both CGHD and PGHD. All bone turnover markers can be significantly improved in GHD children after rhGH replacement treatment for 6 months, with a tendency of increase in bone mass.