Cynthia A Jackevicius1, Harlan M Krumholz2, Joseph S Ross3, Maria Koh4, Alice Chong4, Peter C Austin5, Therese A Stukel5, Paymon Azizi5, Dennis T Ko6. 1. Department of Pharmacy Practice and Administration, College of Pharmacy, Western University of Health Sciences, Pomona, California, USA; Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada; Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California, USA; Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, Ontario, Canada; University Health Network, Toronto, Ontario, Canada. Electronic address: cjackevicius@westernu.edu. 2. Department of Medicine, Section of Cardiovascular Medicine, Yale University School of Medicine, Center for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, Connecticut, USA; Department of Epidemiology and Public Health, Section of Health Policy and Administration, New Haven, Connecticut, USA; Robert Wood Johnson Clinical Scholars Program, New Haven, Connecticut, USA. 3. Department of Medicine, Section of Cardiovascular Medicine, Yale University School of Medicine, Center for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, Connecticut, USA; Department of Internal Medicine, Section of General Internal Medicine, Yale School of Medicine, New Haven, Connecticut, USA. 4. Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada. 5. Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada; Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, Ontario, Canada. 6. Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada; Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, Ontario, Canada; Division of Cardiology, Schulich Heart Centre, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada.
Abstract
BACKGROUND: It is uncertain whether beta-blockers (BBs) are beneficial in contemporary stable patients with prior myocardial infarction (MI). Therefore, we sought to examine the effectiveness of BB use in this population. METHODS: We conducted a cohort study with the use of administrative databases of patients ≥ 65 years of age, alive on April 1, 2012 (index date) with a hospital discharge diagnosis of MI within the previous 3 years. The primary outcome was time to death or hospitalization for MI or angina 1 year after the index date, with inverse probability of treatment weighting. RESULTS: We included 33,811 patients with prior MI, of whom 21,440 (63.4%) were dispensed a BB. The median age was 78 years, and 56% were male. There was no difference in the 1-year hazard of death/hospitalization for MI or angina (14.8% vs 14.7%, hazard ratio 1.00, 95% confidence interval 0.94-1.07; P = 0.90) in those receiving vs not receiving BB. Similarly, there was no difference in the individual end points in composite nor in 3-year outcomes. Subgroup analysis by age, sex, MI timing, MI type, heart failure, and atrial fibrillation found no benefit. Patients with a history of revascularisation treated with BBs had a lower rate of the composite outcome compared with those without such history (P = 0.006 for interaction) at 1 year but not at 3 years. CONCLUSIONS: In this large contemporary population-based observational study of older stable patients with prior MI, BBs were not associated with a reduction in major cardiovascular events or mortality in those with MI within the previous 3 years. This study supports the need to conduct contemporary clinical trials evaluating the use of BBs after MI.
BACKGROUND: It is uncertain whether beta-blockers (BBs) are beneficial in contemporary stable patients with prior myocardial infarction (MI). Therefore, we sought to examine the effectiveness of BB use in this population. METHODS: We conducted a cohort study with the use of administrative databases of patients ≥ 65 years of age, alive on April 1, 2012 (index date) with a hospital discharge diagnosis of MI within the previous 3 years. The primary outcome was time to death or hospitalization for MI or angina 1 year after the index date, with inverse probability of treatment weighting. RESULTS: We included 33,811 patients with prior MI, of whom 21,440 (63.4%) were dispensed a BB. The median age was 78 years, and 56% were male. There was no difference in the 1-year hazard of death/hospitalization for MI or angina (14.8% vs 14.7%, hazard ratio 1.00, 95% confidence interval 0.94-1.07; P = 0.90) in those receiving vs not receiving BB. Similarly, there was no difference in the individual end points in composite nor in 3-year outcomes. Subgroup analysis by age, sex, MI timing, MI type, heart failure, and atrial fibrillation found no benefit. Patients with a history of revascularisation treated with BBs had a lower rate of the composite outcome compared with those without such history (P = 0.006 for interaction) at 1 year but not at 3 years. CONCLUSIONS: In this large contemporary population-based observational study of older stable patients with prior MI, BBs were not associated with a reduction in major cardiovascular events or mortality in those with MI within the previous 3 years. This study supports the need to conduct contemporary clinical trials evaluating the use of BBs after MI.