Proton pump inhibitor use is not associated with severe COVID-19 related outcomes: A propensity score weighted analysis of a national veteran cohort

Background and Aims: Low pH deactivates most pathogens, including coronaviruses. Proton pump inhibitors (PPIs) are potent gastric acid suppressing medications. Whether PPI use vs non-use is associated with severe Coronavirus disease-2019 (COVID-19) outcomes remains uncertain. We aimed to compare severe COVID-19 outcomes between current outpatient PPI users and non-users. Methods: We conducted a retrospective propensity score-weighted analysis of a national cohort of US veterans with established care who tested positive for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) through January 9, 2021, and who had 60 days of follow-up. The positive test date was the index date. Current outpatient PPI use up to and including the index date (primary exposure) was compared to non-use, defined as no PPI prescription fill in the 365 days prior to the index date. The primary outcome was a composite of use of mechanical ventilation or death within 60 days. Weighted logistic regression models evaluated severe COVID-19 outcomes between current PPI users vs non-users. Results: Of 97,674 Veterans with SARS-CoV-2 testing, 14,958 tested positive (6262 [41.9%] current PPI users, 8696 [58.1%] non-users) and comprised the analytic cohort. After weighting, all covariates were well-balanced. In the weighted cohort, there was no difference in the primary composite outcome (8.2% vs 8.0%; OR 1.03, 95% CI 0.91-1.16), secondary composite outcome, nor individual component outcomes between current PPI users and non-users. There was no significant interaction between age and PPI use on outcomes. Conclusion: Among patients with SARS-CoV-2 infection, current PPI use vs non-use is not associated with severe COVID-19 outcomes.