Alfacalcidol (alpha D3) and calcium in osteoporosis

In a prospective, randomized study, 66 osteoporotic postmenopausal women (mean age, 67 years) were scheduled to receive either alfacalcidol 0.25 microgram twice daily together with calcium 500 mg twice daily (treatment group, n = 24) or placebo twice daily with calcium 500 mg twice daily (control group, n = 42) for three years. In the treatment group, bone mineral content at the distal radius may have increased by 2% compared to a significant decrease of 7.8% in the control group. The difference between the two groups was also significant. Since the dose of alfacalcidol and calcium remained unadjusted, frequent hypercalciuria, as well as occasional mild, transient elevations of serum calcium, were observed in the treatment group. No changes in serum creatinine levels or creatinine clearance throughout the study were observed. The two groups did not differ with respect to the frequency of clinical side effects, which were mainly gastrointestinal and probably related to the calcium supplementation. Alfacalcidol and calcium may prevent further bone loss in women suffering from postmenopausal osteoporosis.