Population-based study of statins, angiotensin II receptor blockers, and angiotensin-converting enzyme inhibitors on pneumonia-related outcomes.

BACKGROUND Studies suggest that statins and angiotensin-converting enzyme (ACE) inhibitors might be beneficial for the treatment of infections. Our purpose was to examine the association of statin, ACE inhibitor, and angiotensin II receptor blocker (ARB) use with pneumonia-related outcomes. METHODS We conducted a retrospective cohort study using Department of Veterans Affairs data of patients aged ≥ 65 years hospitalized with pneumonia. We performed propensity-score matching for 3 medication classes simultaneously. RESULTS Of 50119 potentially eligible patients, we matched 11498 cases with 11498 controls. Mortality at 30 days was 13%; 34% used statins, 30% ACE inhibitors, and 4% ARBs. In adjusted models, prior statin use was associated with decreased mortality (odds ratio [OR], 0.74; 95% confidence interval [CI], .68-.82) and mechanical ventilation (OR, 0.81; 95% CI, .70-.94), and inpatient use with decreased mortality (OR, 0.68; 95% CI, .59-.78) and mechanical ventilation (OR, 0.68; 95% CI, .60-.90). Prior (OR, 0.88; 95% CI, .80-.97) and inpatient (OR, 0.58; 95% CI, .48-.69) ACE inhibitor use was associated with decreased mortality. Prior (OR, 0.73; 95% CI, .58-.92) and inpatient ARB use (OR, 0.47; 95% CI, .30-.72) was only associated with decreased mortality. Use of all 3 medications was associated with reduced length of stay. CONCLUSIONS Statins, and to a lesser extent ACE inhibitors and ARBs, are associated with improved pneumonia-related outcomes. Prospective cohort and randomized controlled trials are needed to examine potential mechanisms of action and whether acute initiation at the time of presentation with these infections is beneficial.