Are beta2-agonists responsible for increased mortality in heart failure?

Area of Science:

• Cardiology
• Pulmonology
• Pharmacology

Background:

• Previous retrospective studies indicated a potential increased mortality risk associated with beta-2 agonist (B2A) use in heart failure (HF) patients.
• The severity of HF, often measured by natriuretic peptide levels, has not been fully accounted for in prior analyses of B2A use and outcomes.

Purpose of the Study:

• To investigate the association between beta-2 agonist (B2A) use and mortality in a heart failure (HF) population.
• To adjust for HF severity, using B-type natriuretic peptide (BNP) levels, in the assessment of B2A therapy's impact on mortality.

Main Methods:

• Retrospective cohort study of 1294 patients in an HF Disease Management Programme with a mean follow-up of 2.9 years.
• B2A use, dosage, and duration were confirmed via chart review; pulmonary function was documented.
• Mortality was compared between B2A users and non-users using unadjusted and adjusted Kaplan-Meier survival analyses, controlling for clinical factors and BNP levels.

Main Results:

• Unadjusted analysis showed significantly higher mortality rates in B2A users (HR 1.304, P=0.028).
• After adjusting for age, sex, medications, comorbidities, smoking, COPD, and BNP levels, the association between B2A use and overall mortality was no longer significant (HR 1.043, P=0.783).
• B2A users were older, more likely male, had a history of smoking, COPD, asthma, and were less likely to use beta-blockers.

Conclusions:

• This retrospective study found no significant relationship between beta-2 agonist (B2A) therapy and long-term mortality in heart failure (HF) patients when adjusted for population characteristics, including BNP levels.
• These findings contrast with previous reports and suggest B2A use may not be associated with increased mortality in HF when accounting for disease severity.
• Further large-scale, prospective studies are warranted to definitively establish the risk-benefit profile of B2As in the management of heart failure.