Antihypertensive medications and risk of community-acquired pneumonia

Abstract
Objective To determine whether angiotensin-converting enzyme (ACE) inhibitors and other antihypertensives are associated with risk of pneumonia. Methods We conducted a nested case–control study of incident pneumonia in a subcohort of hypertensive adults insured by several large commercial plans throughout the United States. Individuals with pneumonia were matched on age, sex, region, and subscriber status with up to 10 controls free of pneumonia at the time of case diagnosis. We examined use of β-blockers, calcium channel blockers, ACE inhibitors (lipophilic and hydrophilic), angiotensin receptor blockers, and thiazides in the prior 3 and 12 months. Results A total of 7429 cases of pneumonia occurred among 305 958 hypertensive individuals. Risk of pneumonia was higher among users of β-blockers [adjusted odds ratio (OR) 1.11; 95% confidence interval (CI) 1.03–1.19], calcium channel blockers (adjusted OR 1.09, 95% CI 1.00–1.17), and lipophilic ACE inhibitors (adjusted OR 1.15, 95% CI 1.03–1.28) in the preceding 3 months; risks were also higher for use in the preceding 12 months. We observed lower risk with thiazide use in the preceding 3 months (adjusted OR 0.90, 95% CI 0.81–0.99) and hydrophilic ACE inhibitor use in the preceding year (adjusted OR 0.86, 95% CI 0.75–0.99). Conclusion In this population of middle-aged Americans with hypertension, we observed a modestly higher risk of pneumonia with use of β-blockers, calcium channel blockers, and lipophilic ACE inhibitors. These results are consistent with possible differences in noncardiovascular outcomes among users of antihypertensives and other commonly used cardiovascular drugs but require confirmation in other populations.