Background: Globally, cardiovascular disease (CVD) is the leading cause of death. Beta-blocker medications have well-established survival benefit for myocardial infarction and heart failure. However, CVD frequently coexists with chronic obstructive airways disease (COPD), a disease in which beta-blockers are traditionally avoided.
Aim: We sought to investigate the adverse respiratory effects associated with long-term beta-blocker treatment in patients with cardiac disease, and presumed high risk of COPD.
Methods: In this prospective cohort study, patients admitted with acute cardiac disease were recruited from the cardiology unit of a tertiary referral hospital. The treating cardiologist determined beta-blocker treatment, independent of the study. Repeated measures of spirometry and respiratory symptom scores were assessed over 12 months. Respiratory exacerbations, cardiac events and survival were recorded over 6 years. Outcomes were compared according to beta-blocker exposure.
Results: Sixty-four subjects participated, 30 of whom received beta-blockers. Beta-blockers did not adversely affect spirometry, respiratory symptoms or survival. However, considering two categories of respiratory exacerbations (symptom-based vs treated), subjects taking beta-blockers accumulated increased annual risk (relative risk (RR) 1.30, 95% confidence interval (CI) 1.11–1.53, P= 0.001 and RR 1.37, 95% CI 1.09–1.72, P= 0.008) and concluded with overall increased risk (RR 3.67, 95% CI 1.65–8.18, P= 0.001 and RR 4.03, 95% CI 1.26–12.9, P= 0.019), when compared with the group not taking beta-blockers.
Conclusion: Long-term beta-blocker treatment did not adversely affect lung function, respiratory symptom scores or survival, but was associated with increased risk of respiratory exacerbations.