Investigating the adverse respiratory effects of beta-blocker treatment: six years of prospective longitudinal data in a cohort with cardiac disease

Authors


  • Funding: None.

  • Conflict of interest: None.

Belinda Cochrane, Department of Medicine, Campbelltown Hospital, Therry Road, Campbelltown, NSW 2560, Australia. Email: belindacochrane@bigpond.com

Abstract

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.

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