A Comparison of Calcium, Calcitriol, and Alendronate in Corticosteroid-Treated Premenopausal Patients with Systemic Lupus Erythematosus

Abstract

To assess bone mineral density (BMD) changes in patients with systemic lupus erythematosus (SLE) undergoing longterm therapy with corticosteroids (CS) while taking calcium, calcitriol, or alendronate. The primary endpoint was BMD changes at 2 years. Premenopausal SLE patients were randomized into 3 groups according to medication: calcium carbonate 500 mg bd (calcium alone), calcitriol 0.25 microg bd plus calcium carbonate 500 mg bd (calcitriol + calcium), and alendronate 70 mg/week plus calcium carbonate 500 mg bd (alendronate + calcium). BMD was measured at baseline and at the end of the first and second years. Ninety-eight patients were recruited. There were 33 patients taking calcium alone, 33 calcitriol + calcium, and 32 alendronate + calcium. On randomization, median duration of CS use was 2.5 years (range 0-20 yrs). Seventy-seven patients (78.6%) completed the study (23 taking calcium alone, 27 calcitriol + calcium, 27 alendronate + calcium). There were no significant differences in mean CS dosages among the 3 groups at the time of BMD measurements. After 2 years, there were no significant changes in BMD in the calcium-alone and calcitriol + calcium groups, apart from a 0.93% (p < 0.001) reduction in total hip BMD in the calcium-alone group. In contrast, the alendronate + calcium group showed significant increases in BMD of 2.69% (p < 0.001) in the lumbar spine and 1.41% (p < 0.001) in total hip. Both calcium alone and calcitriol + calcium preserved lumbar spine BMD in premenopausal patients with SLE taking longterm CS at 2 years, whereas alendronate + calcium led to increases in BMD in lumbar spine and total hip. Premenopausal women taking CS should be considered for osteoporosis prophylaxis.