Proton-pump inhibitor use and risk of community-acquired pneumonia in congenital heart disease patients

Background: Adults with congenital heart disease (CHD) are at elevated risk of hospitalization for community acquired pneumonia (CAP). Proton-pump inhibitors (PPIs) have been shown to be a risk factor for CAP in adult and pediatric general populations. This study explored the association between PPI use and subsequent CAP hospitalizations in the adult CHD population.Methods: Using the Danish National Patient Registry, we performed a nested case-control study of adults with CHD who had been admitted to the hospital for CAP between 1996 and 2017. The timing and dose of PPI were evaluated in the year preceding the CAP admission. Logistic regression measured the impact of timing and dose of PPI on the subsequent CAP admission.Results: In total, 618 adult CHD patients were admitted for CAP during the study period. The adjusted odds ratio (OR) was 2.21 (95% confidence interval (CI) 1.66-2.94) for CAP in current PPI users compared with non-users. The OR amongst current PPI users was further elevated for males, those older than 65 years old and those with severe/univentricular CHD [3.59 (95% CI 2.33-5.52), 2.30 (95% CI 1.55-3.41), 2.35 (95% CI 1.13-4.87)], respectively. Segmenting by dose, the OR for CAP patients taking low-dose and high-dose PPI was 2.11 (95% CI 1.38-3.22) and 2.29 (95% CI 1.60-3.26), respectively.Conclusions: Adults with CHD prescribed a PPI are at elevated risk of hospitalization for CAP in the following 90 days. The risk for CAP admission is further increased for those prescribed high-dose PPIs, males, those older than 65 years of age, and those with severe/univentricular CHD.