Clinical trial: comparison of alendronate and alfacalcidol in glucocorticoid‐associated osteoporosis in patients with ulcerative colitis

Summary Background  Bone loss is often observed in patients with ulcerative colitis, particularly if they require glucocorticoids. Aim  To determine whether the bisphosphonate, alendronate, is safe and effective in preserving bone mass compared to the active vitamin D3, alfacalcidol, in ulcerative colitis patients receiving glucocorticoids. Methods  Thirty-nine patients with ulcerative colitis and treated with glucocorticoids were randomized to receive alendronate (5 mg/day) or alfacalcidol (1 μg/day) daily for 12 months. Loss of bone mass was evaluated by bone mineral density, bone resorption by urinary N-telopeptide for type I collagen, and bone formation by serum bone alkaline phosphatase. Results  Alendronate, but not alfacalcidol, significantly increased bone mineral density in the lumbar spine. Alendronate decreased serum bone alkaline phosphatase levels, but alfacalcidol did not. Urinary N-telopeptide for type I collagen levels decreased in both groups, but were significantly lower in the alendronate group. There were no significant differences in the adverse events in the two groups. Conclusion  Our study indicates that alendronate is a safe, well-tolerated and more effective therapy than alfacalcidol for preventing glucocorticoid-associated bone loss in patients with ulcerative colitis.