Effects of one-year hormone replacement therapy on peripheral bone mineral content in patients with osteoporotic spine fractures.

A double-blind, placebo-controlled study on 31 patients with osteoporotic spine fractures was performed in order to assess the effects of one-year cyclical estrogen/gestagen replacement therapy (Trisequens, Novo) on peripheral bone mineral content and bone turnover. Bone mineral content was measured by single-photon absorptiometry with 125I before, and 6 and 12 months after start of therapy. Calcium, phosphate, alkaline phosphatase, parathyroid hormone, calcidiol, calcitonin and 2-hour urinary hydroxyproline excretion were measured to evaluate bone turnover. After 12 months, forearm bone mineral content showed a significant increase (p less than 0.02) in the treatment group, whereas in the control group no statistically significant change in peripheral bone mass was observed. Parameters of bone metabolism showed a decrease in hydroxyproline excretion (p less than 0.02) as well as alkaline phosphatase (p less than 0.01) and no changes in parathyroid hormone, calcidiol, and calcitonin. These results demonstrate that one-year cyclical estrogen/gestagen replacement therapy improves peripheral bone mineral content measured by single-photon absorptiometry. This effect appears to be induced by an inhibition of bone resorption.