Effect of calcitriol on bone mineral density in premenopausal Chinese women taking chronic steroid therapy. A randomized, double blind, placebo controlled study

Abstract

Objective. To study the effect of chronic steroid therapy on bone mineral density (BMD) in premenopausal women with normal menstrual cycles and its treatment. Methods. A double blind placebo controlled study to evaluate 81 premenopausal women with systemic lupus erythematosus (SLE), aged 31.1 ± 6 years, taking chronic steroid therapy, with a mean cumulative prednisone dose of 28 ± 16.2 g. They were randomly allocated to 3 groups: Group 1:0.5 μg calcitriol and 1200 mg calcium daily; Group 2:1200 mg calcium and placebo calcitriol; and Group 3: both placebo calcitriol and placebo calcium. Results. Baseline T score at the lumbar spine was > -1 in 56.8% and < -2.5 in 3.7% of the patients. At the end of 2 years, patients in the calcitriol group exhibited a significant increase of 2.1 ± 2.4% in BMD at the lumbar spine compared to baseline value (p < 0.05). This change was not significantly different from the respective change in either calcium or placebo group (0.4 ± 2.9% and 0.3 ± 3.5%, respectively). No significant changes were observed in any treatment group in BMD at the hip or radius. Alkaline phosphatase increased both in the placebo (baseline: 57.5 ± 17.5 IU/l; year 2:60.9 ± 15.3 IU/l) and the calcium group (baseline: 53.6 ± 16.6 IU/l; year 2:59.0 ± 22.8 IU/l), but this increase reached statistical significance only in the calcium group, while the same variable remained stable in the calcitriol group (baseline: 53.9 ±14.1 IU/l; year 2:54.6 ± 12.3 IU/l). Conclusion. Premenopausal women with SLE taking prolonged steroid therapy had lower BMD but showed no significant bone loss over the 2 year study period. The beneficial effect of calcitriol treatment in these premenopausal women was small, at least when it was instituted late in the course of steroid therapy.