OBJECTIVES : Antiplatelet therapy is first-line treatment after cardiac revascularization and necessary to prevent both immediate and long-term complications. Timely medication initiation after revascularization (also known as primary adherence) is critical to avoid morbidity, mortality, and increased healthcare costs. Currently, the rate at which patients never fill these prescriptions in the US is currently unknown. The purpose of this study is to determine primary nonadherence rates of antiplatelet therapy after revascularization.

METHODS : The study population included patients who were newly initiated on clopidogrel or ticagrelor at discharge after percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG). Primary nonadherence was defined as the absence of evidence of a fill for a medication within 30 days of the prescription written date. Discharge prescription data were merged with available pharmacy fill data to calculate time to first fill and primary nonadherence rates. Patients were excluded from the study if they were not discharged to home or there was no evidence of any fill for any medications in the 12 months prior to their 30-day nonadherence date. Patient demographics, procedure type, and medication burden were evaluated using t-test to identify predictors of nonadherence.

RESULTS : A total of 663 patients were included for study, with 270 prescribed ticagrelor and 393 prescribed clopidogrel. The overall primary nonadherence rate was 17%, with rates for ticagrelor and clopidogrel at 21% and 15% respectively. Patients who did not fill their antiplatelet therapy were more likely to have had a CABG and more home medications at admission.

CONCLUSIONS : The rates of primary nonadherence for these antiplatelet therapies after revascularization are similar to those from other countries. Knowing how often patients with cardiovascular disease never fill important medications is critical as we continue to develop medication adherence solutions and advance care management during transitions.