Treatment of post-menopausal osteoporosis with recombinant human growth hormone and salmon calcitonin: a placebo controlled study

OBJECTIVE: The usefulness of GH in the treatment of post-menopausal osteoporosis (PMO) is still debated. We have studied the effects of recombinant human GH (rhGH) given alone or in combination with salmon calcitonin (sCT) in the treatment of PMO. PATIENTS: Thirty women with established PMO (aged 61.1 +/- 4.4 years) were divided into 3 groups of 10 and randomly assigned to 3 treatment sequences: rhGH (12IU/day) s.c. for 7 days, followed by sCT (50 IU/day) s.c. for 21 days and by 61 days without treatment (group 1); placebo for 7 days, followed by sCT for 21 days and by 61 days without treatment (group 2); rhGH for 7 days, followed by placebo for 21 days, and by 61 days without treatment (group 3). Each cycle was repeated 8 times (24 months). MEASUREMENTS: At days 0, 8, 29 and 90 of each cycle, serum IGF-I, calcium, phosphate, osteocalcin, alkaline phosphatase and urinary excretion of calcium, hydroxyproline and pyridinoline cross-links (Pyr) were measured. At months 0, 6, 12, 18 and 24, bone mineral density (BMD) was measured by dualphoton absorptiometry (DPA), at lumbar spine (LS), femoral shaft (F) and distal radius (DR). RESULTS: A significant increase in serum osteocalcin and urinary calcium, hydroxyproline and Pyr was detected after each rhGH period. In group 1, BMD at lumbar spine increased by 2.5% at year 2; in contrast, significant (P < 0.05) decreases in BMD-LS values were found in patients treated with CT and placebo (group 2) and with GH and placebo (group 3). BMD-F did not show any significant change in patients of group 2, but a significant (P < 0.05) decrease was found in groups 1 and 3. BMD-DR did not show any significant change with respect to baseline in any of the three groups. No significant difference between the three groups was found in bone mass at the three different regions. CONCLUSIONS: Our study demonstrates that treatment with rhGH increases bone turnover in postmenopausal osteoporotic women. Combined treatment with rhGH and CT over a period of 24 months is able to maintain bone mass at lumbar spine and distal radius, but induces a decline at femoral shaft; therefore, it does not seem particularly useful in the therapy of post-menopausal osteoporosis