CHANGES IN BONE-MINERAL DENSITY, BODY-COMPOSITION, AND LIPID-METABOLISM DURING GROWTH-HORMONE (GH) TREATMENT IN CHILDREN WITH GH DEFICIENCY

Adults with childhood onset GH deficiency (GHD) have reduced bone mass , increased fat mass, and disorders of lipid metabolism. The aim of th e present study was to evaluate bone mineral density (BMD), bone metab olism, body composition, and lipid metabolism in GHD children before a nd during 2-3 yr of GH treatment (GHRx). Forty children with GHD, mean age 7.9 yr, participated in the study of bone metabolism and body com position; and an additional group of 17 GHD children, in the study of lipid metabolism. Lumbar spine BMD, total body BMD, and body compositi on were measured with dual-energy x-ray absorptiometry. Volumetric BRI D (bone mineral apparent density, BMAD) was calculated to correct for bone size. BMD, BMAD, lean tissue mass, bone mineral content, fat mass , and percentage body fat were expressed as so scores (SDS), in compar ison with normative data of the same population. Lumbar spine BMD and BMAD and total body BMD were all decreased at baseline. All BMD variab les increased significantly during GHRx, lumbar spine BMD SDS, already after 6 months of treatment. Lean tissue mass SDS increased continuou sly. Bone mineral content SDS started to increase after 6 months GHRx. Fat mass SDS decreased during the first 6 months of GHRx and remained stable thereafter. Biochemical parameters of bone formation and bone resorption did not differ from normal at baseline and increased during the first 6 months of GHRx. Serum 1,25 dihydroxyvitamin D increased c ontinuously during GHRx, whereas PTH and serum calcium remained stable . Lipid profile was normal at baseline. Atherogenic index had decrease d and apolipoprotein A1 (Apo-A1) had increased after 3 yr of treatment . In conclusion, children with GHD have decreased bone mass. BMD, toge ther with height and lean tissue mass, increased during GHRx. GHRx had a beneficial effect on lipid metabolism.