Study objective: To determine the rates of hospitalizations and emergency department (ED) visits during cardioselective and nonselective beta-blocker therapy in patients with asthma and/or chronic obstructive pulmonary disease (COPD).
Design: Retrospective, observational cohort study.
Data source: Electronic medical records database.
Patients: A total of 11,592 adult patients with asthma and/or COPD, identified from August 1, 1997-December 31, 2005, who were taking beta-blockers for at least 30 days or had never received a beta-blocker (controls).
Measurements and main results: Of these patients, 3062 were taking cardioselective and 690 nonselective beta-blockers; 7840 were controls. The primary end point for the beta-blocker groups was the rate of hospitalizations and ED visits/patient-year of beta-blocker therapy relative to the control group. In patients with asthma with or without concomitant COPD, cardioselective beta-blockers were associated with a relative risk of 0.89 (95% confidence interval [CI] 0.53-1.50) for hospitalizations and 1.40 (95% CI 1.20-1.62) for ED visits compared with controls. Nonselective beta-blockers were associated with a relative risk of 2.47 (95% CI 1.37-4.48) for hospitalizations and 1.21 (95% CI 0.91-1.62) for ED visits. In patients with COPD only, cardioselective beta-blockers were associated with a relative risk of 0.64 (95% CI 0.43-0.96) for hospitalizations and 1.19 (95% CI 1.02-1.39) for ED visits. Nonselective beta-blockers were associated with a relative risk of 1.02 (95% CI 0.52-2.02) for hospitalizations and 0.51 (95% CI 0.33-0.80) for ED visits.
Conclusion: In patients with asthma with or without COPD, both cardioselective and nonselective beta-blocker use increased hospitalizations and ED visits compared with controls. Thus, these patients should receive beta-blocker therapy only if their cardiac risk exceeds their pulmonary risk and if they have concomitant cardiac disease for which beta-blockers decrease mortality, such as previous acute myocardial infarction or chronic heart failure. In patients with COPD only, cardioselective beta-blockers slightly increased the risk of ED visits but reduced the risk of hospitalizations. Nonselective beta-blocker therapy in these patients reduced the rate of ED visits and total visits. These findings suggest a larger safety margin with beta-blocker therapy in patients with COPD only than in those with asthma with or without COPD.