Improving anti-platelet therapy adherence in the Veterans Health Administration: A randomized multi-site hybrid effectiveness-implementation study protocol

Background: P2Y12 inhibitors are critical following percutaneous coronary intervention (PCI) with stent placement; they reduce the risk of stent thrombosis and myocardial infarction. Despite the importance of the therapy, non-adherence is common among Veterans. Methods and results: Our main objective is to conduct a multi-site randomized stepped wedge trial to test the effectiveness of a multi-faceted intervention to improve adherence to P2Y12 inhibitors and PCI outcomes as well as formatively evaluate and refine the intervention implementation process. The primary outcomes of the study are the proportion of patients whose P2Y12 inhibitor prescription was filled at the time of hospital discharge following PCI with stent placement as well as the proportion of patients who were adherent based on the pharmacy refill data in the year after PCI hospital discharge. We will also assess the secondary outcomes such as bleeding, myocardial infarction, stroke, and mortality among these patients, and the cost-effectiveness of the intervention. The study was conducted at Veterans Health Administration (VA) PCI sites. At each site, we enrolled patients over a 6-month period and followed them for 12 months after PCI. Additionally, we collected qualitative data to identify contextual factors and to assess barriers and facilitators to the implementation and maintenance of the intervention. Conclusions: The study will add to the current state of knowledge on improving medication adherence in patients receiving PCI with stent implantation. Moreover, the study includes an extensive examination of the implementation process and will contribute to the field of implementation science. Clinical trial registration: ClinicalTrials.gov Identifier: NCT01609842 https://clinicaltrials.gov/ct2/show/NCT01609842?term=clopidogrel+adherence&cntry1=NA%3AUS&rank=1