JMIR Publications

ABSTRACT

Background:

Based on high quality evidence, guidelines recommend the long-term use of secondary prevention medications post-myocardial infarction (MI) to help reduce recurrent cardiovascular events and death. Unfortunately, discontinuation of recommended medications post-MI is common. Observational evidence suggests that prescriptions covering a longer duration at discharge from hospital are associated with greater long-term medication adherence. We proposed the first interventional study to evaluate the impact of longer prescription duration at discharge post-MI on long-term medication adherence.

Objective:

The overarching goal of this study is to reduce the morbidity and mortality of post-MI patients through improved long-term cardiac medication adherence. The specific objectives include: 1. Assess the impact on long-term cardiac medication adherence following the implementation of (1) a standardized increase in discharge prescription length to 90-days with 3 repeats in post-MI patients as compared to (2) education alone and usual care; 2. Assess the cost implications of the prolonged initial discharge prescriptions as compared to usual care; 3. Compare clinical outcomes between longer (>60 days) versus shorter prescription durations; 4. Collect baseline information to inform a multi-centre interventional study (i.e., simple monthly proportions of 1-year adherence by hospitals in Ontario).

Methods:

A quasi-experimental, interrupted time series design to evaluate the impact of a multifaceted intervention to implement longer duration prescriptions versus usual care on long-term cardiac medication adherence among post-MI patients. Intervention and setting includes: (i) intervention group 1 – one cardiac centre and non-cardiac hospital received revised standardized discharge prescription forms supporting the dispensation of 3 months’ worth of cardiac medications and 3 repeats, coupled with education; (ii) intervention group 2 – four other sites, which only received education but no discharge form; and (iii) the remaining hospitals within the province which did not receive any intervention package (i.e., usual care). Administrative databases will be used to measure all outcomes. Adherence to four classes of cardiac medications: statins, beta-blockers, angiotensin system inhibitors, and secondary antiplatelets (e.g., prasugrel, clopidogrel, or ticagrelor) will be assessed.

Results:

The primary outcome is long-term cardiac medication adherence assessed at 365 days from discharge. We calculated that 24 pre and 12 post-intervention intervals in each group will achieve 80% power to detect an immediate increase (intercept change) of 10% in the monthly proportion of patients with adherence (proportion of days covered [PDC] ≥80%) to their cardiac medication regimen at one-year.

Conclusions:

The results have the potential to redefine best practices regarding discharge prescribing policies for patients post-MI. A policy of standardized maximum-duration prescriptions at the time of discharge post-MI is a simple intervention that has the potential to significantly improve long-term medication adherence, thus decreasing cardiac morbidity and mortality. If effective, this low-cost intervention to implement longer duration prescriptions post-MI could be easily scaled. Clinical Trial: ClinicalTrials.gov: NCT03257579, registered June 16, 2017.