Early β-Blocker Use and Clinical Outcomes in Acute Myocardial Injury: A Retrospective Cohort Study

Abstract

Background

Acute myocardial injury is defined by elevated cardiac troponin levels with a rising and/or falling pattern, and is associated with increased mortality risk compared to patients without myocardial injury. The role of β-blockers in patients with acute myocardial injury remains unclear.

Methods

This multicenter, retrospective cohort study used data from the Tianjin Health and Medical Data Platform to assess the impact of early β-blocker use on 1-year all-cause mortality and major adverse cardiovascular events (MACE) in acute myocardial injury patients, employing a new user and target trial emulation design. Propensity score matching was applied, and Cox regression was used to calculate hazard ratios (HR) and 95% confidence intervals (CI).

Results

After propensity score matching, a total of 25,966 participants were included: 8667 to the β-blocker group and 17,299 to the non-β-blocker group. A total of 4113 deaths (15.8%) and 5795 MACE (22.3%) occurred. Compared with nonusers, β-blocker was associated with the reduced risk of all-cause mortality (HR: 0.89, 95% CI: 0.83-0.95) and MACE (HR: 0.90, 95% CI: 0.85-0.95). In the subgroup analysis, β-blockers were associated with a significantly reduced risk of mortality in patients without stroke (HR 0.85, 95% CI: 0.78-0.93), while no significant association was observed in patients with stroke (HR 1.04, 95% CI: 0.93-1.16).

Conclusions

Early use of β-blockers is associated with the reduced risk of 1-year mortality in patients with acute myocardial injury. To more accurately assess the therapeutic effects, prospective trials are necessary, and these data provide key research directions for future trials.