Abstract and Introduction
Abstract
Background Prior studies have demonstrated that patients with high-risk acute myocardial infarction (AMI) are less likely to receive guideline-directed medications during hospitalisation. It is unknown if this paradox persists following discharge. We aimed to assess if persistence with guideline-directed medications post discharge varies by patients' risk following AMI.
Methods Data were analysed from two prospective, multicentre US AMI registries. The primary outcome was persistence with all prescribed guideline-directed medications (aspirin, β-blockers, statins, angiotensin-antagonists) at 1, 6 and 12 months post discharge. The association between risk and medication persistence post discharge was assessed using multivariable mixed-effect models.
Results Among 6434 patients with AMI discharged home, 2824 were considered low-risk, 2014 intermediate-risk and 1596 high-risk for death based upon their Global Registry of Acute Coronary Event (GRACE) 6-month risk score. High-risk was associated with a lower likelihood of receiving all appropriate therapies at discharge compared with low-risk patients (relative risk (RR) 0.90; 95% CI 0.87 to 0.94). At 12 months, the rate of persistence with all prescribed therapies was 61.5%, 57.9% and 45.9% among low-risk, intermediate-risk and high-risk patients, respectively. After multivariable adjustment, high-risk was associated with lower persistence with all prescribed medications (RR 0.87; 95% CI 0.82 to 0.92) over follow-up. Similar associations were seen for individual medications. Over the 5 years of the study, persistence with prescribed therapies post discharge improved modestly among high-risk patients (RR 1.05; 95% CI 1.03 to 1.08 per year).
Conclusions High-risk patients with AMI have a lower likelihood of persistently taking prescribed medications post discharge as compared with low-risk patients. Continued efforts are needed to improve the use of guideline-directed medications in high-risk patients.
Introduction
Among patients with acute myocardial infarction (AMI), guidelines and performance measures aim to improve quality of care delivered by encouraging provision of evidence-based medications in all eligible patients. Prior studies have demonstrated that high-risk patients with AMI often do not receive guideline-directed medications during hospitalisation, a phenomenon that has been referred to as the 'risk-treatment paradox'. However, little is known about whether such paradox exists for use of prescribed medications following hospital discharge.
Both provision of appropriate medications and continued use of these medications are necessary to realise their potential to reduce the risk of mortality and recurrent AMI. While it is known that physicians are less likely to optimally manage high-risk patients with AMI at the time of discharge, it is unknown whether long-term use of these guideline-directed medications differs by patients' risk after discharge or whether use of guideline-directed medical therapy post discharge has improved over time. Identifying such treatment gaps can enable targeted interventions to improve the use and persistence with cardiac medications.
The objective of this study was to assess persistence with guideline-directed therapies during longitudinal follow-up in two large, prospective, multicentred registries of patients with AMI. We assessed prescription of aspirin, statins, β-blockers and ACE inhibitors/angiotensin receptor blockers (ACEI/ARBs) to patients with AMI at low, intermediate and high risk for all-cause mortality based on the Global Registry of Acute Coronary Event (GRACE) risk score at hospital discharge. We then sought to describe persistence with these medications in the year following hospital discharge, as well as assess temporal trends in persistence with these cardiac medications across risk strata over the course of this study.