PRELIMINARY-STUDY OF THE EFFECTS OF GROWTH-HORMONE SUBSTITUTION THERAPY ON BONE-MINERAL DENSITY AND SERUM OSTEOCALCIN LEVELS IN ADULTS WITHGROWTH-HORMONE DEFICIENCY

In order to evaluate the consequences of pituitary insufficiency on bo ne mineral status, bone mineral density (BMD) was measured by dual-ene rgy X-ray absorptiometry in 33 patients (aged 22-6 5 years) with pitui tary insufficiency. BMD of the lumbar spine and femoral neck was decre ased. Twenty of the patients were randomized to receive either recombi nant human growth hormone (GH), 0.25 IU/kg/week for 6 months (0. 125 I U/kg/week during the first month), or placebo. Serum osteocalcin level s increased significantly during GH administration. In the GH-treated group, there was no change in lumbar spine BMD and a small but signifi cant decrease in femoral neck BMD (p < 0.05) after 6 months. Treatment periods longer than 6 months are needed to evaluate the potential ben eficial effect of GH on BMD. This is in accordance with our previous f indings of an increase in forearm BMD after 12 months of GH substituti on therapy.