Vertebral fracture efficacy during risedronate therapy in patients using proton pump inhibitors

Summary Recent evidence suggests that proton pump inhibitor (PPI) use may affect fracture risk, an important issue for patients being concurrently treated for osteoporosis. The results of our post hoc analysis showed that, regardless of PPI concomitant use, risedronate significantly reduced the risk of new vertebral fractures compared with placebo. Introduction Recent evidence suggests that PPI use may affect fracture risk, an important issue for patients being concurrently treated for osteoporosis. Moreover, data suggest that concomitant use of PPIs may wane the antifracture effect of bisphosphonates. We explored the relationship between concomitant use of PPIs and incident vertebral fractures among patients treated with risedronate or placebo. Bone mineral density (BMD) and upper gastrointestinal (UGI) adverse events (AEs) were also assessed. Methods This study is a post hoc analysis of a subset of patients participating in three prospective, randomized, placebo-controlled clinical trials, with durations of up to 3 years, which evaluated the efficacy of risedronate in reducing fracture risk: Vertebral Efficacy with Risedronate Trial–MultiNational (VERT-MN); Vertebral Efficacy with Risedronate Trial–North America (VERT-NA); and the risedronate Hip Intervention Program (HIP). Results Total enrollment included 2,729 risedronate and 2,725 placebo patients. Concomitant acid-suppressing drugs were used by 8.8% of the total population (n=482). Regardless of PPI concomitant use, risedronate significantly reduced the risk of new vertebral fractures compared with placebo (risk reduction: PPI users 57%, p=0.009; PPI nonusers 38%, p<0.001). BMD increased with risedronate, independent of PPI use. PPI users were at a 2.5-fold greater risk of experiencing at least one UGI AE compared with non-users. Conclusions Risedronate significantly reduced the risk of new vertebral fractures compared with placebo, regardless of PPI concomitant use.