Objective: To evaluate long-term efficacy of risedronate in osteoporotic postmenopausal patients with inflammatory bowel disease (IBD).
Design: A prospective, parallel, open-label, 2-year extension study of a randomized, double-blind, 1-year clinical trial. Eighty-one osteoporotic postmenopausal women with IBD were treated with risedronate (n = 40) or placebo (n = 41). Bone mineral density (BMD), biochemical bone turnover markers, and vertebral and nonvertebral fractures were assessed throughout the study. Data were analyzed using the intent-to-treat principle.
Results: Significant (P < 0.05) differences were observed between risedronate and placebo groups at 1-, 2-, and 3-year follow-up visits in bone turnover markers and in lumbar spine, trochanter, and femoral neck BMD. In participants treated with risedronate, the percentage of changes from baseline in bone turnover markers and in lumbar spine, trochanter, and femoral neck BMD were significantly (P < 0.05) higher at 2- and 3-year follow-up in comparison with baseline and 1-year follow-up, with a significant (P < 0.05) difference between the 2- and 3-year follow-up visits. At the end of the study, the cumulative risk of vertebral and nonvertebral fractures was significantly (P < 0.05) lower in the risedronate group than in the placebo group. The relative risk for new vertebral fractures was 0.456 (95% CI: 0.134-1.559, P = 0.211) and 0.296 (95% CI: 0.121-0.721, P = 0.007) and was 0.209 (95% CI: 0.023-1.867, P = 0.161) and 0.137 (95% CI: 0.030-0.620, P = 0.010), respectively, for new nonvertebral fractures after 2 and 3 years of risedronate treatment.
Conclusions: In postmenopausal osteoporotic women with IBD, long-term treatment with risedronate is effective in increasing BMD and reducing vertebral and nonvertebral fracture risk.