Association of Beta-Blocker Therapy With Cardiovascular Outcomes in Patients With Stable Ischemic Heart Disease.

Background: Previous studies have failed to show a cardioprotective benefit of beta-blockers in patients with stable coronary artery disease (CAD).
Objectives: This study sought to determine the association between beta-blockers and cardiovascular events in patients with stable CAD using a new user design.
Methods: All patients aged >66 years undergoing elective coronary angiography in Ontario, Canada, from 2009 to 2019 with diagnosed obstructive CAD were included. Exclusion criteria included heart failure or a recent myocardial infarction, as well as having a beta-blocker prescription claim in the previous year. Beta-blocker use was defined as having at least 1 beta-blocker prescription claim in the 90 days preceding or after the index coronary angiography. The main outcome was a composite of all-cause mortality and hospitalization for heart failure or myocardial infarction. Inverse probability of treatment weighting using the propensity score was used to account for confounding.
Results: This study included 28,039 patients (mean age: 73.0 ± 5.6 years; 66.2% male), and 12,695 of those (45.3%) were newly prescribed beta-blockers. The 5-year risks of the primary outcome were 14.3% in the beta-blocker group and 16.1% in the no beta-blocker group (absolute risk reduction: -1.8%; 95% CI: -2.8 to -0.8; HR: 0.92; 95% CI: 0.86-0.98; P = 0.006). This result was driven by reductions in myocardial infarction hospitalization (cause-specific HR: 0.87; 95% CI: 0.77-0.99; P = 0.031), whereas no differences were observed in all-cause death or heart failure hospitalization.
Conclusions: In patients with angiographically documented stable CAD without heart failure or a recent myocardial infarction, beta-blockers were associated with a small but significant reduction in cardiovascular events at 5 years.
Competing Interests: Funding Support and Author Disclosures This study is funded in part by a Foundation Grant (FDN 154333) from the Canadian Institutes of Health Research. The analyses, conclusions, opinions, and statements expressed herein are solely those of the authors and do not reflect those of the funding or data sources; no endorsement is intended nor should one be inferred. Dr Godoy has received the Frederick Banting and Charles Best Canada Graduate Scholarship (Doctoral Research Award) from the Canadian Institutes of Health Research. Dr Farkouh has received research grants from AstraZeneca, Novo Nordisk, and Novartis; and has served as a consultant to Otitopic. Dr Wijeysundera has received support from a Canada Research Chair in Structural Heart Disease Policy and Outcomes. Dr Krumholz has received expenses and/or personal fees from UnitedHealth, Element Science, Eyedentifeye, and F-Prime; is a co-founder of Refactor Health and HugoHealth; and is associated with contracts, through Yale New Haven Hospital, the Centers for Medicare & Medicaid Services and, through Yale University, the Food and Drug Administration, Johnson & Johnson, Google, and Pfizer. Dr Ko has received support from the Jack Tu Research Chair in Cardiovascular Outcomes Research. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
(Copyright © 2023 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)