Medication Safety Events After Acute Myocardial Infarction Among Veterans Treated at VA Versus Non-VA Hospitals

Introduction: Fragmentation of health care across systems can contribute to mistakes in prescribing and filling medications among patients treated for myocardial infarction (MI). We sought to compare omissions, duplications, and delays in outpatient medications used for secondary prevention among veterans treated for MI at Veterans Affairs (VA) versus non-VA hospitals.Methods: We utilized national VA and Centers for Medicare and Medicaid Services data (2012-2018) to identify veterans 65 years or older hospitalized for MI and measured the use of outpatient medications for secondary prevention in the 30 days after MI among those treated at VA versus non-VA hospitals.Results: A total of 118,456 veterans experiencing MI were included; of which 102,209 were hospitalized at non-VA hospitals. An omission in any medication class occurred more frequently among veterans treated at non-VA versus VA hospitals (82.8% vs 67.8%, P < 0.001). In multivariable modeling, the odds of omissions in any medication class were higher among those treated at non-VA versus VA hospitals (odds ratio: 3.04; 95% CI: 2.88-3.20). Duplications occurred more frequently in veterans treated at non-VA versus VA hospitals: 1.9% versus 1.6% had 1 or more for non-VA versus VA hospitals (P < 0.001). Veterans treated at non-VA hospitals were more likely to have delays of 3 days or more in prescription fills after hospital discharge (88.4% vs 70.6% across all classes, P < 0.001).Conclusions: Omissions, duplications, and delays in outpatient prescribing of secondary prevention medications were more common among 118,456 veterans treated at non-VA versus VA hospitals for MI. Interventions aimed at improving care transitions and optimizing medication use among veterans treated at non-VA hospitals should be implemented.