A new study has found that taking acid reducing drugs, including proton pump inhibitors, can significantly increase the risk for Clostridium difficile (C. difficile) infection. The lead author of the study, which involved a meta-analysis of 30 separate studies, characterized the association between C. difficile and proton pump inhibitors and other heartburn drugs seen in the analysis as “robust.”
Proton pump inhibitors are used to treat conditions such as gastroesophageal reflux disease (GERD), stomach and small intestine ulcers, and inflammation of the esophagus. Over-the-counter proton pump inhibitors are used to treat frequent heartburn are sold under the names:
- Dexilant (dexlansoprazole)
- Nexium (esomeprazole magnesium)
- Prevacid (lansoprazole) and OTC Prevacid 24hr
- Prilosec (omeprazole) and Prilosec OTC
- Protonix (pantoprazole sodium)
- Vimovo (esomeprazole magnesium and naproxen)
- Zegerid (omeprazole and Sodium bicarbonate) and Zegerid OTC
Previous studies have indicated that use of proton pump inhibitors could increase the risk for C. difficile. In a Drug Safety Communication issued in February, the U.S. Food & Drug Administration (FDA) warned that taking proton pump inhibitors may be associated with the occurrence of Clostridium difficile–associated diarrhea (CDAD), a severe form of diarrhea caused by C. difficile bacteria. At the time, the agency said it was working with manufacturers to include information about the increased risk of CDAD with use of proton pump inhibitors in the drug labels.
This new meta-analysis included studies published through January 2012 out of the U.S., U.K., Canada, and Israel. Twenty-four studies were from single centers, five were multicenter, two were from general practice research databases, and one was from a general practice clinic. Five studies exclusively addressed community-acquired C. difficile 24 addressed hospital-acquired infection, 1 covered both community- and hospital-acquired C. difficile and 1 examined infection rates in a long-term care facility.
Each of the separate analyses showed a significant association between acid suppression and C. difficile, with pooled effect estimates of 1.67 for studies looking at proton pump inhibitors. For H2 blocker, sthe estimate was 1.44.
Why proton pump inhibitors and similar drugs might be increasing the risk for C. difficile wasn’t clear, as gastric acid does not kill C. difficile spores. However, it does kill the vegetative form of the bacteria. The study authors also pointed out that acid suppression therapy has also been shown to delay gastric emptying, which could improve survival of the vegetative form of C. difficile.