Prior beta blockers use is independently associated with increased inpatient mortality in patients presenting with acute myocardial infarction

Background: Beta blockers (BBs) are recommended for patients presenting with acute myocardial infarction. However, the effects of prior BBs use on inpatient mortality in patients presenting with acute myocardial infarction (AMI) are unknown.

Methods: This was a retrospective cohort study of patients presenting with AMI in Florida Hospital Orlando from January 1, 2013 to December 31, 2014. Data were collected prospectively, as part of the Acute Coronary Treatment and Intervention Outcomes Network (ACTION) Registry.

Results: 1128 patients were included in the analysis, with 354 (31.4%) patients on home BBs and 774 (68.6%) not on home BBs on presentation. Patients in prior BBs group were older, had higher incidence of multiple comorbidities, and were more likely to take cardiovascular medications. During hospitalization, Patients in prior BBs group were more likely to develop decompensated heart failure (9.9% vs. 3.6%, P<0.001), less likely to have STEMI (33.9% vs. 54.4%, P<0.001), and subsequently less PCI (73.2% vs. 81.3%, P=0.002), but higher inpatient mortality (8.8% vs. 4.8%, P=0.009). In multivariable logistic regression analysis, prior BBs use was independently associated with increased inpatient mortality (adjusted OR 3.15, 95% CI 1.44-6.87, P=0.004), as well as in GRACE model (adjusted ratio=1.83, 95% CI 1.01-3.34, P<0.047). However, prior BBs use did not contribute significantly to predict inpatient mortality on the basis of GRACE model in terms of discrimination and calibration.

Conclusions: Prior BBs use was independently associated with increased inpatient mortality, and should be considered a high risk marker for patients presenting with acute myocardial infarction.