プロトンポンプ阻害薬と骨合併症

Digestive Diseases and Calcium/Bone. Proton pump inhibitor and bone complications.

　プロトンポンプ阻害薬（PPI）による大腿骨近位部および椎体の有意な骨折リスク増加については，これまでに多くの観察研究に基づく報告がなされている。しかし，メタ解析によれば，投与期間との関連は認められていない。また，観察研究では観察された疫学的関連が原因と結果なのか，検討していないかまたは残っている交絡因子によるものなのかを明らかにすることは不可能である。また，明確な骨折リスク増加の機序も明らかとはなっていない。これらのことから，この問題に決着をつけるためには無作為化比較対照試験が必要と考える。

　Many observational studies indicated a significant association between PPI use and increased risk of hip and vertebral fractures, but no evidence of duration effect was founded by meta-analysis. However, observational studies cannot clarify whether the observed epidemiologic association is a causal effect or a result of unmeasured/residual confounding. Furthermore, a mechanism through which PPI increase the risk of fracture has not been proven. Overall, PPI use dose not interfere with calcium absorption in most instances and, therefore, it is unlikely that PPI influence fracture risk through interfering with absorption of dietary calcium. There is no consistent effect of PPI on bone mineral density as assessed by dual energy X-ray absorptiometry testing. Thus, randomized controlled studies are required to confirm of refute these results. At this time, the author does not recommend discontinuing PPI in patients with a history of fracture or those at increased risk of fracture. However, clinicians should still endeavor to avoid using PPI in situations where benefits are minimal or clinical indication are lacking.