Comparative efficacy of hormone replacement therapy, etidronate, calcitonin, alfacalcidol, and vitamin K in postmenopausal women with osteoporosis: The Yamaguchi Osteoporosis Prevention Study

Purpose To assess the comparative effectiveness of several medications on bone mineral density, biochemical bone markers, and the incidence of vertebral fractures in postmenopausal women with osteoporosis. Methods A total of 396 postmenopausal women, aged 50 to 75 years, were allocated randomly to six equal-sized groups: hormone replacement therapy, etidronate, eel calcitonin, alfacalcidol, vitamin K (menatetrenone), or control (no treatment). Thoracic and lumbar spine radiographs, bone mineral density at the distal radius, and markers of bone turnover were assessed at baseline and every 3 months during the 2-year study. Results Compared with baseline, the 2-year mean changes in bone mineral density were 2.0% for hormone replacement therapy, −0.5% for etidronate, 1.6% for calcitonin, −3.6% for alfacalcidol, −1.9% for vitamin K, and −3.3% for control. Seventeen (26%) of the 66 control patients developed new vertebral fractures. Compared with controls, the relative risks of vertebral fracture were 0.35 (95% confidence interval [CI]: 0.14 to 0.83) for hormone replacement therapy, 0.40 (95% CI: 0.17 to 0.92) for etidronate, 0.41 (95% CI: 0.17 to 0.93) for calcitonin, 0.56 (95% CI: 0.26 to 1.12) for alfacalcidol, and 0.44 (95% CI: 0.20 to 0.99) for vitamin K. Conclusion We observed significant reductions in the incidence of vertebral fractures with hormone replacement therapy, etidronate, and calcitonin, and significant improvements in bone mineral density with hormone replacement therapy and calcitonin.