Proton Pump Inhibitors versus Histamine-2 Receptor Antagonists and Risk of Pneumonia in Patients with Acute Stroke

Background Pneumonia is a serious complication of stroke. Several studies have indicated that certain gastric acid suppressants may be associated with an increased risk of pneumonia in hospitalized patients. However, the association between type of acid suppressant and pneumonia in acute stroke patients remains controversial. The purpose of this study was to clarify the association between the type of acid suppressant and the occurrence of pneumonia in acute stroke patients. Methods This retrospective observational study used data from the national Japanese Diagnosis Procedure Combination inpatient database. We identified patients who were admitted to acute-care hospitals with stroke. The outcome was the occurrence of pneumonia assessed using diagnostic codes. We performed propensity score-matched analysis to compare the outcome between proton pump inhibitor (PPI) users and histamine-2 receptor antagonist (H2RA) users. Results A total of 77,890 stroke patients were identified, of whom 63,980 were prescribed H2RAs and 13,910 were prescribed PPIs. Overall, 1490 (10.7%) of the patients receiving PPIs and 6401 (10.0%) of the patients receiving H2RAs developed pneumonia after stroke. After propensity score matching, the incidence of pneumonia in PPI users was not different from that in H2RA users (odds ratio: 1.10, 95% confidence interval: .99-1.21). Conclusion No significant difference in the incidence of pneumonia was seen between users of PPIs and H2RAs after acute stroke.