Long‐term skeletal effects of recombinant human growth hormone (rhGH) alone and rhGH combined with alendronate in GH‐deficient adults: a seven‐year follow‐up study

Abstract

Background GH-deficient patients respond to recombinant human GH (rhGH) replacement therapy by increasing bone mineral density (BMD) at a rate of about 1% a year for at least 4 years. Predictive factors for a beneficial effect on bone are a low bone mass at baseline and gender. Whether the beneficial skeletal effects of GH are sustained in the long term remains to be established. It is also not known whether osteoporotic GH-deficient patients may require additional antiresorptive drugs and whether this treatment would be effective concomitantly with GH replacement. Design We performed a long-term, controlled study in 30 GH-deficient adults: 15 with osteoporosis and 15 control subjects with low bone mass. All patients were treated with rhGH for at least 4 years; thereafter, 3 years of additional alendronate treatment was given to patients with osteoporosis, while controls continued on GH therapy alone. The GH dose was individualized to maintain an IGF-I within the normal reference range for the duration of the study, and was equal between genders. Results At the end of 4 years of rhGH replacement therapy, a significant increase in mean lumbar spine BMD was observed in both the osteoporosis group (3.6%) and the control group (7.0%), with no significant difference between groups. Males had a larger increase in BMD than females (P = 0.032). After 4 or 5 years of GH treatment patients with persisting osteoporosis received additional alendronate (10 mg/day) for 3 years. Lumbar spin…