Cyclical etidronate increases lumbar spine bone density in patients on long-term glucocorticosteroid therapy

To determine whether cyclical etidronate modifies bone density in patients on chronic glucocorticosteroid therapy, annual bone density measurements were performed on 55 patients receiving glucocorticosteroids who were randomised to either continuous calcium supplementation or cyclical etidronate plus calcium supplementation in this secondary prevention study. Median L1-L4 lumbar spine bone density decreased by 0.7% in the calcium treated group after one year but increased by 3.1% in the group treated by calcium and etidronate (p = 0.00116). Median L1-L4 bone density decreased by 2.8% from baseline after two years in the calcium treated group but increased by 4.7% from baseline in the group treated by calcium and etidronate (p = 0.04). There were no significant effects of treatment on femoral neck density. Cyclical etidronate and calcium increased lumbar spine bone density in patients established on prednisolone treatment over a two-year period but had no effect on femoral density.