Abstract 164: Adherence to Oral Antiplatelet (OAP) Therapy among ACS Patients Undergoing Percutaneous Coronary Intervention (PCI)
Background: The benefit of oral antiplatelet therapy following PCI is well established. Dual antiplatelet therapy is guideline recommended treatment for one year following a PCI.
Objective: To examine discontinuation and adherence rates of oral anti-platelet therapy of patients with acute coronary syndrome (ACS) in the year following a PCI.
Methods: From the HealthCore Integrated Research Environment, patients ≥18 years old and hospitalized for ACS (inpatient hospitalization with a primary diagnosis for acute myocardial infarction or unstable angina) during 8/1/09-6/30/13 (index hospitalization) were identified and followed up to 12 months. Patients with an OAP prescription fill within 6 months prior to the index hospitalization, those with a fill for ticagrelor at any time during the study period, those simultaneously starting clopidogrel and prasugrel following the index hospitalization, and those who had a coronary artery bypass graft during index hospitalization were excluded. OAP prescription utilization patterns were examined drug class (clopidogrel or prasugrel) as a whole and by branded versus generic clopidogrel. Medication adherence to OAP therapy was assessed as discontinuation (a period of >45 days not covered by supply of OAP therapy) and the proportion of days covered (PDC; calculated as total day supply during the follow-up divided by days from first fill to end of follow-up).
Results: Of 38,626 ACS patients identified, 20,753 were revascularized with PCI during the index hospitalization, and 17,237 (83.1%) went on to fill an OAP prescription (12,714 with clopidogrel as first OAP treatment; 4,523 with prasugrel). On average, patients filled OAP medication 6.7 days following index hospitalization discharge (71% filled on discharge date).
The study also found that 20% of patients discontinued OAP therapy during follow-up and 86% of follow-up days were covered by an OAP therapy supply on average. Other medication classes within the same patients had higher discontinuation rates and lower PDC: anti-hypertensive (27% discontinuation; 82% PDC), anti-diabetics (27%; 83%) statins (27%; 82%), and beta-blockers (37%; 72%).
Discontinuation rates were considerably lower in patients taking generic clopidogrel versus those filling branded drug (11% for generic vs. 37% for branded) and PDC was higher for generic clopidogrel (90% PDC vs. 75% for branded).
Conclusions: Adherence to OAP therapy compares favorably to adherence rates of other cardiovascular/metabolic medications taken by the same patients. Lower out of pocket costs were also associated with better refill compliance. The above findings present healthcare providers with an opportunity to further improve on medication adherence post-PCI in ACS patients by reducing the economic burden on patients.
Author Disclosures: D.M. Kern: None. D. Bhandary: A. Employment; Significant; AstraZeneca LP. O. Tunceli: None. B. Wu: None.
- © 2014 by American Heart Association, Inc.