Individuals who use proton pump inhibitors (PPIs) appear to be at heightened risk of pneumonia, as reported in a study.
For the study, researchers applied a self-controlled case series design and used data from Swedish registries for medications, diagnoses, and mortality. Conditional fixed-effect Poisson regression was used to calculate incidence rate ratios (IRR) for pneumonia during PPI-exposed periods vs unexposed periods in the same individuals. Analyses were stratified by PPI treatment duration, sex, age, and smoking-related diseases.
The analysis included 519,152 individuals with at least one pneumonia episode during the study period. There were 307,709 periods of PPI treatment and 507,016 periods without PPI-use. The mean follow-up was 12.3 years.
Compared with nonexposed periods, PPI-exposed periods were associated with a 73-percent increased risk of pneumonia (IRR, 1.73, 95 percent confidence interval [CI], 1.71–1.75) overall. The risk was consistently high for each of the duration periods of PPI exposure (1–30 days: IRR, 2.59, 95 percent CI, 2.55–2.63; 31–90 days: IRR, 2.25, 95 percent CI, 2.22–2.28; >90 days: IRR, 2.20, 95 percent CI, 2.17–2.23). The IRRs were high across strata of PPI-treatment duration, sex, age, and smoking-related disease status.
Meanwhile, no evidence of association was found between histamine type-2 receptor antagonist use and risk of pneumonia (IRR, 1.08, 95 percent CI, 1.02–1.14).