Association between angiotensin-converting enzyme inhibitors or angiotensin receptor blockers and community-acquired pneumonia: A nationwide population propensity-score matching study

Background Few large-scale cohort studies have investigated the association between community acquired pneumonia and the use of angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin II receptor blockers (ARBs). We aimed to study whether using ACEIs or ARBs had protective effects for community acquired pneumonia. Methods This database cohort study was conducted retrospectively in Taiwan. The hypertensive patients were the target population of this study. Patients with ARB use were defined as our first study cohort. The second study cohort comprised patients who used ACEI. Propensity-score matching at 1:1 was used between ARB users and non-ARB users. We recruited 67 944 participants for the ARB study and 58 062 participants for the ACEI study. The same matching was also performed between ACEI users and non-ACEI users. Cox proportional hazard regression was used to analyze the risk of the outcome of viral pneumonia. Results The hazard ratio of community acquired pneumonia for ARB users relative to non-ARB users was 0.33. The hazard ratio of community acquired pneumonia was 0.71 times in ACEI users compared with ACEI nonusers. In stratification analysis, both ARB and ACEI both exhibited a protective effect for community acquired pneumonia in each age and sex group. In the analysis of the effects of therapy duration, patients using ARB for fewer than 100 days exhibited a greater reduction in the risk of community acquired pneumonia (adjusted HR = 0.58) compared with the non-ARB cohort. For the ACEI study, patients who used ACEI for 121 to 450 days were more likely to exhibit reduced risks of community acquired pneumonia (adjusted HR = 0.5). Conclusion Both ACEI and ARB uses were associated with decreased risk of community acquired pneumonia infection.