PCV2 Real-World Outcomes of Antithrombotic Therapies in Patients with Coronary Artery Disease That Require Long-Term Oral Anticoagulation

Abstract

In patients with coronary artery disease (CAD), guidelines recommend daily low-dose aspirin (ASA) and/or P2Y12 inhibitors for long-term maintenance. However, patients may also be indicated to receive oral anticoagulants (OAC) long-term, raising important questions about safety and effectiveness of combination OAC/antiplatelet regimens. This research aims to assess real-world effectiveness and safety in patients with CAD receiving OAC with or without ASA. This retrospective cohort study used medical and pharmacy claims data linked to electronic health record (EHR) data at an integrated delivery network (IDN) in Texas between January 2014 and December 2019. Patients were followed up to 12 months after their index date, defined as the date of their first OAC claim. Inclusion criteria were: (1) age ≥18 years, (2) stable CAD (diagnosed or ≥6 months post-coronary revascularization procedure), (3) IDN health plan continuous enrollment ≥6 months pre-index and ≥12 months post-index, (4) proportion of days covered by OAC ≥80% for the first 6 months post-index, and (5) no P2Y12 inhibitors post-index. Patients were grouped by ASA use from outpatient EHR data. Major adverse cardiovascular events (MACE: cardiovascular-related death, non-fatal stroke, and non-fatal MI) were measured for effectiveness, and major bleeding events were measured for safety. 418 patients (n=297, OAC-only; n=121, OAC/ASA) met study criteria with mean (SD) age 75.8 (9.7) years. Overall, patients were primarily white (68.4%), male (59.3%), and insured through Medicare (71.1%). Direct OACs were more common than warfarin (67.7% vs. 32.3%). In the OAC-only and OAC/ASA groups, MACE occurred in four (1.3%) and one (0.8%, P=NS) patient(s), respectively, whereas thirteen (4.4%) and six (5.0%, P=NS) patients, respectively, experienced major bleeding events. Rates of MACE and major bleeding events in this real-world study were low compared to similar randomized controlled trials. Additional larger, randomized studies are needed to compare safety and effectiveness.