Treatment of glucocorticoid-induced osteoporosis with alfacalcidol/calcium versus vitamin D/calcium

Vitamin D/calcium substitution is generally regarded as an effective first step treatment for glucocorticoid-induced osteoporosis (GIOP). The aim of our study was to evaluate the efficacy of the active vitamin D metabolite alfacalcidol (1 alpha) compared with the native vitamin D-3 in patients with established GIOP with or without vertebral fractures. Patients on long-term corticoid therapy were given either 1 mu g alfacalcidol plus 500 mg calcium per day (group A, n = 43) or 1000 IU vitamin D-3 plus 500 mg calcium (group B, n = 42). The two groups were alike in age range, sex ratio, percentages of underlying diseases, average initial bone density values (lumbar spine: mean T-score -3.28 and -3.25, respectively), and rates of vertebral and nonvertebral fractures. During the 3-year study we found a small but significant increase of lumbar spine density in group 1 alpha (+2.0%, P < 0.0001) and no significant changes at the femoral neck. In the D-3 group, there were no significant changes at both sites. At the end of the study, 12 new vertebral fractures had occurred in 10 patients of the group 1 alpha and 21 in 17 patients of the D-3 group. In accordance with the observed fracture rates, the alfacalcidol group showed a significant decrease in back pain (P < 0.0001) whereas no change was seen in the vitamin D group. We conclude that with the doses used in this trial, alfacalcidol is superior to vitamin D in the treatment of established GIOP.