Post-myocardial Infarction (MI) Care: Medication Adherence for Secondary Prevention After MI in a Large Real-world Population

Secondary medication prevention after acute myocardial infarction (MI) is strongly recommended in international guidelines, but actual use, adherence, and outcomes in current clinical practice are largely unknown. Therefore, the aims of this study were to determine the current adherence to medications for secondary prevention after MI and to estimate the association between medication adherence and mortality and major adverse cardiovascular events (MACE) in a large real-world population. Using a large health care claims database, patients were selected who had been hospitalized with MI between 2012 and 2015 (N = 4349). Adherence to drug therapy after discharge was measured as the medication possession rate (MPR) per year (0%–100%, indicating the number of days with medication supplied relative to the total number of days) for the individual drug classes. The relationship between MPR and the risk of MACE and death was assessed by using Cox proportional hazards regression models. A high proportion of patients with low MPR (0%–79%) was observed for all drug classes (47.6% for dual antiplatelet therapy (DAPT), 23.5% for lipid-lowering drugs (LLDs), 47.3% for angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, and 88.1% for beta-blockers (BB). Women and elderly patients were less likely to receive LLDs. Patients with high adherence to DAPT, LLDs, and angiotensin-converting enzyme inhibitors/angiotensin receptor blockers (MPR ≥80%) had a significantly reduced risk for all-cause mortality and MACE (LLD-group). In a real-life setting, adherence to drug therapy for secondary cardiovascular prevention after MI was only moderate. Increased use of evidence-based treatment such as DAPT and LLDs in current clinical practice may improve long-term outcomes of patients with MI. Moreover, providing clear information, improved care transition, and a close collaboration between clinicians and physicians involved in an early outpatient follow-up is required.