Proton pump inhibitors: Clostridium difficile infections

Data on the adverse effect profile of proton pump inhibitors continue to accumulate. In addition to increasing the risk of bacterial pneumonia, proton pump inhibitors appear to increase the risk of intestinal Clostridium difficile infection. A meta-analysis of epidemiological studies showed a statistically significant increase in C. difficile infection among patients taking proton pump inhibitors, most of whom were hospital patients.The estimated relative risk was 1.7 for primary infections (95% confidence interval (95CI): 1.5 to 2.1) and 2.5 for recurrent infections (95Ch: 1.2 to 5.4). When the proton pump inhibitor was coadministered with an antibiotic, the estimated relative risk was 2.0 (95CI: 1.0 to 3.7). Other meta-analyses published in 2012 provided similar results. A similar increased risk has been observed with H2 antagonists. The presumed mechanism is the reduction in gastric acidity induced by these drugs. In practice, proton pump inhibitors should not be used indiscriminately, especially in hospital patients and in persons at increased risk of C. difficile infection. Patients should be informed of new data on the adverse effects of the medications they are taking so that they can weigh the harms and benefits.