Association between preoperative proton pump inhibitor use and postoperative infectious and renal complications following major elective surgery

Background — Use of poton pump inhibitors (PPIs) is associated with increased risk of Clostridioides difficile–associated colitis, pneumonia, and acute kidney injury. Their effect on postoperative complications is unknown. The objective of this study was to investigate the association between PPIs and the risk of C. difficile–associated colitis, pneumonia, and acute kidney injury following elective surgery.

Methods — In this population-based, matched cohort study, we identified patients who had filled a PPI prescription within 90 days before major elective surgery (2010–2019). Study outcomes included C. difficile–associated colitis, pneumonia, acute kidney injury, gastrointestinal bleeding, and death within 90 days of surgery. We matched patients 1-to-1 on the basis of age, sex, procedure, date of surgery, and a propensity score predicting PPI exposure. We used logistic regression to evaluate between-group differences.

Results — Of 313 163 patients, 89 047 (28.4%) used PPIs; of those, 79 681 were successfully matched to patients who did not use PPIs. The risk of the composite outcome (acute kidney injury, pneumonia, C. difficile–associated colitis, and death) among the patients who used PPIs was slightly higher than among the patients who did not use PPIs (10.6% v. 10.2 4%), and was driven primarily by a higher rate of pneumonia among those who used PPIs (4.0% v. 3.7%). There was a lower rate of gastrointestinal bleeding among the patients who used PPIs (1.6% v. 1.8%). The risk of pneumonia was most pronounced in the subgroup undergoing hip and knee replacement (odds ratio 1.21, 95% confidence interval 1.08–1.36; p = 0.001). There were no significant differences between groups with regard to rates of C. difficile–associated colitis or acute kidney injury.

Conclusion — We found that preoperative PPI use was associated with higher rates of pneumonia, particularly among patients undergoing hip and knee replacement surgery, and lower rates of gastrointestinal bleeding. Patients taking a PPI before surgery should be targeted for therapies aimed at reducing pneumonia risk, such as aggressive chest physiotherapy, following their operation.