A small dose of human parathyroid hormone(1-34) increased bone mass in the lumbar vertebrae in patients with senile osteoporosis.

Intermittent treatment with human parathyroid hormone (hPTH) has been shown to increase cancellous bone mineral density (BMD) in osteoporosis, but its effects on cortical bone remain controversial. In this study, the effects of hPTH(1-34) administered at a dose of 6 micrograms (20 units) per day subcutaneously for 26 weeks were investigated in 16 patients with senile osteoporosis. The changes in BMD in lumbar vertebrae were measured using dual energy x-ray absorptiometry. BMD in the second metacarpal bone was simultaneously measured with radiogrammetry to find changes in BMD in cortical bone. Serum and urinary biochemical parameters were also evaluated. The lumbar BMD increased significantly at the end of the treatment without decrease in the cortical bone mass. Biochemical markers of bone formation were also elevated, while markers of bone resorption did not show striking changes during the treatment. In conclusion, daily administration of low doses of hPTH(1-34) stimulated bone formation and increased bone mass in patients with senile osteoporosis without combination with another therapeutic agent.