Comparison of clopidogrel vs. ticagrelor medication adherence in patients with acute coronary syndrome

OBJECTIVE: Medication nonadherence to dual antiplatelet therapy increases major cardiovascular events. In this study, we investigated patients' post-acute coronary syndrome (ACS) medication adherence to clopidogrel and ticagrelor over a 12-month period. Furthermore, we also examined the factors that may affect medication adherence in this patient population. PATIENTS AND METHODS: This study included 509 patients who were scheduled for dual antiplatelet therapy for one year following ACS (October 2018-December 2019). A proportion of days covered (PDC) method, based on a pharmacy database system, was used to determine their medication adherence. Medication adherence was defined as > 80% PDC. RESULTS: No difference was found between clopidogrel and ticagrelor in terms of medication adherence (68.3% vs. 64.6%, p = 0.39). Moreover, higher education levels (B = 3.24, CI: 1.17-8.9, p = 0.023) and percutaneous coronary intervention (PCI) as a revascularization option (B = 0.35, CI: 0.17-0.71, p = 0.004) predicted medication adherence independently. CONCLUSIONS: In this research, medication adherence was found to be similar between the clopidogrel and ticagrelor groups. It was also predicted by higher education levels and revascularization with PCI.