Researchers have compared the safety of two commonly prescribed beta-blockers for asthma patients experiencing heart failure with reduced ejection fraction (HFrEF). Their research, “Comparative Risk of Asthma Exacerbation With Carvedilol Versus Metoprolol in Heart Failure Patients,” analyzed data from more than 120,000 patients and suggests that carvedilol may be associated with fewer asthma exacerbations than metoprolol. The study was published in the Annals of Allergy, Asthma & Immunology.
The retrospective cohort study leveraged a large multicenter electronic health record database of adult patients with HFrEF and asthma to analyze asthma exacerbation rates, mean exacerbation counts and Kaplan-Meier survival analysis.
Key findings from the study include:
- Among patients with both heart failure and asthma, 8.45% of those on metoprolol experienced asthma exacerbations compared to 7.20% on carvedilol.
- The analysis revealed a risk ratio of 1.17 and an odds ratio of 1.19, indicating a modest but statistically significant difference.
- Patients on metoprolol averaged 2.97 exacerbations during the study period, while those on carvedilol averaged 2.56.
- Kaplan-Meier survival analysis confirmed lower exacerbation-free survival for metoprolol users (p < 0.001).
“The theory was that there would probably be more reactions with carvedilol because of the mixed interaction [known to trigger exacerbations], but what I found was that patients who are taking metoprolol, which is the medication that doesn’t react with the airway directly due to beta selectivity, actually shows higher risk of asthma exacerbation in this patient population,” Rasha Khan, DO, of Philadelphia’s Jefferson Einstein Hospital, told Healio. Dr. Khan is the study’s principal investigator and author.
According to researchers, although beta-blockers are essential in guideline-directed therapy for heart failure with reduced ejection fraction (HFrEF), their use in patients with asthma has long raised concerns. Despite being a nonselective beta-blocker, this study suggests that carvedilol may offer better tolerability for asthma patients compared to metoprolol, Dr. Khan said.
Researchers emphasized that although the difference is modest, it could influence prescribing decisions for clinicians managing patients with both conditions.
“This study is not enough to say we should recommend carvedilol in patients with asthma, but it’s enough to maybe plant a seed to consider investigating that a little further and broadening the scope of what our general understanding is,” said Dr. Khan.
