Starting atenolol after a myocardial infarction among patients without recorded heart failure is associated with a lower two-year risk of major adverse cardiovascular events compared with bisoprolol, though it shows no significant difference in all-cause mortality, according to data from an observational cohort study published Sept. 22 in NEJM Evidence.
French Health Data System Tracks Post-Infarction Outcomes
Researchers led by Thomas Laurenceau, MD, utilized the French National Health Data System to identify adults hospitalized in the Paris area. The study focused on patients who experienced a new myocardial infarction between January 1, 2008, and December 31, 2018. Eligible participants received prescriptions for either atenolol or bisoprolol within two days of hospital discharge. Patient outcomes were tracked for up to two years. The cohort had a mean age of 58 years, and 79% of the participants were male. Investigators evaluated average treatment effects using targeted likelihood estimation.
Atenolol Versus Bisoprolol Clinical Results
Out of 11,558 patients identified in the dataset, 13% started atenolol while 87% started bisoprolol immediately following discharge. The primary outcome measured was major adverse cardiovascular events, defined as a composite of cardiac arrest, all-cause mortality, reinfarction, stroke, or hospitalization for heart failure. Secondary outcomes tracked all-cause mortality alone. Compared with bisoprolol, atenolol was associated with average treatment effects of 2.9% for major adverse cardiovascular events and 0.6% for all-cause mortality. Weighted rates for major adverse cardiovascular events reached 11% for the atenolol group and 14% for the bisoprolol group. Corresponding all-cause mortality rates stood at 1% for atenolol and 2% for bisoprolol. These results remained consistent across per-protocol, subgroup, and sensitivity analyses.
Study Limitations and Calls for Randomized Trials
The observational nature of the research leaves open questions regarding other medications in the same drug class. Laurenceau and colleagues noted that the analysis “was restricted to the two most frequently prescribed [beta]-blockers in France, and whether similar comparative effectiveness would be observed for other [beta]-blockers remains unknown.” They added that “a randomized head-to-head trial would be required to confirm these findings.” Editorialists Jose-Angel Perez-Rivera, MD, PhD, and Fabian Blanco-Fernandez, MD, PhD, wrote in an accompanying editorial that “these findings challenge the traditional assumption that all beta-selective beta-blockers exert equivalent clinical effects after MI and generate the hypothesis that individual agents within the class may differ in effectiveness.” They also noted that “the real-world nature of the study adds further value, providing insights into the effectiveness of beta-blocker therapy in routine clinical practice.”
Common Questions Regarding Post-Infarction Beta-Blocker Data
What primary outcome did the NEJM Evidence study measure?
The study measured major adverse cardiovascular events, which included cardiac arrest, all-cause mortality, reinfarction, stroke, or hospitalization for heart failure.
How many patients were included in the French database analysis?
The study analyzed data from 11,558 patients hospitalized in the Paris area with a new myocardial infarction.
What did the accompanying editorial conclude about the findings?
Editorialists Jose-Angel Perez-Rivera and Fabian Blanco-Fernandez stated that the findings challenge the assumption that all beta-selective beta-blockers have equivalent clinical effects after MI.