Beta blockers are a standard of care for patients who have experienced an acute myocardial infarction.1 However, it is unclear how often beta blockers are prescribed after an MI and how effective they are in preventing subsequent MIs in the real world because clinical trials have had mixed results.2-4 We analyzed data from 262,972 patients who experienced their first MI between 2018 and 2023 to determine the incidence of a subsequent MI and whether the risk of subsequent MI was influenced by a beta blocker prescription.
We found that across all demographic groups, 80.5% of patients were prescribed beta blockers within 30 days of their first MI, as seen in Figure 1. Male patients were 6.5% more likely to be prescribed beta blockers than female patients. White patients were 3.4% more likely than Black patients and 2.7% more likely than Hispanic patients to be prescribed beta blockers.
Next, we analyzed whether beta blockers might prevent a subsequent MI. We found that across all demographic groups, those prescribed beta blockers were 16.5% more likely to have a subsequent MI within a year of their initial MI than patients who were not prescribed beta blockers, as seen in Figure 2. These findings held true even when evaluating across patient sex, race, and ethnicity.
Black patients are the most likely to experience a subsequent MI with or without a beta blocker prescription, compared to White or Hispanic patients.
While the results of this study suggest that beta blockers might not be as effective at preventing subsequent MIs as previously thought, further evaluation is needed because our study did not assess the dosage or duration of beta blocker therapy or the medication adherence of the patients, which might have an impact on the medication’s effectiveness.5 Additionally, providers might decide to prescribe beta blockers more frequently for patients who already have a higher risk of a subsequent MI.
Original Publication Date: June 6, 2023
Last Updated: August 2, 2023
