Long-Term Follow-Up After Acute Myocardial Infarction According to Beta-Blocker Dose

Area of Science:

• Cardiology
• Pharmacology
• Public Health

Background:

• Acute myocardial infarction (MI) remains a leading cause of mortality worldwide.
• Beta-blockers are a cornerstone therapy for post-MI patients, but optimal dosing strategies require further investigation.

Purpose of the Study:

• To investigate the association between varying doses of beta-blockers and mortality risk in patients following their first acute myocardial infarction.

Main Methods:

• A nationwide cohort study utilizing the Danish National Patient Registry included 65,125 patients admitted for first-time MI between 2004 and 2014.
• Patients were categorized by daily beta-blocker prescription adherence relative to recommended target doses.
• Cox proportional hazard regression analysis was employed to calculate adjusted mortality rate ratios (MRRs).

Main Results:

• Any prescribed beta-blocker dose demonstrated a significant reduction in mortality compared to no treatment (adjusted MRR ≤ 0.92).
• The most substantial mortality reduction within the first year post-MI was observed with beta-blocker doses exceeding 25% but not more than 50% of the target dose (adjusted MRR = 0.55).
• After one year, doses between 50%-100% of the target dose showed the largest reduction, though not significantly different from the 25%-50% dose range.

Conclusions:

• Beta-blocker treatment, even at sub-target doses, is associated with reduced mortality after acute myocardial infarction.
• Doses of 25%-50% of the recommended target dose appear to maximize mortality reduction within the first year, suggesting higher doses may not confer additional benefits.