Abstract 13006: High Use of Concomitant Antiplatelet Therapy with Oral Anticoagulation in Patients with Atrial Fibrillation: Results from the ORBIT-AF Registry
Background: Treatment with antiplatelet therapy increases the risk of bleeding in patients with atrial fibrillation (AF) receiving oral anticoagulant (OAC) agents. The patterns of concomitant use of these agents in community practice have not been well-defined.
Methods: The ORBIT-AF registry enrolled patients with AF from a broad range of practice settings and collected detailed data on OACs and antiplatelet therapies.
Results: Of 10,098 patients at baseline, 7,688 (76%) were prescribed OAC therapy (dabigatran or warfarin). The majority (4795/7688, 62%) were taking only an OAC, while 35% (2723/7688) were receiving dual therapy with an OAC and single antiplatelet agent (aspirin or ADP inhibitor), and 2% (170/7688) were receiving triple therapy (anticoagulant plus aspirin and ADP inhibitor). Patients prescribed additional antiplatelet therapy were younger (median age 76 for OAC only vs. 75 for dual therapy vs. 73 for triple therapy, p<0.0001), less likely female (47% vs. 34% vs. 29%, p<0.0001), and more likely to have cardiovascular risk factors such as hypertension, hyperlipidemia, and tobacco use (p<0.0001 for comparisons of each). They were less likely to have preserved LV function (71% vs. 66% vs. 58%, p<0.0001), and more likely to have CHADS2 score >=2 (72% vs. 79% vs. 81%, p<0.0001). More than one-third (37%) of patients receiving dual therapy had no prior history of coronary, peripheral, or cerebrovascular disease (Table). Of 75 patients on triple therapy with prior drug eluting stent, 35 (47%) received the stent within the previous year. Six-month unadjusted rates of hospitalization, bleeding, and MI were highest in the triple therapy group.
Conclusions: Patients with AF prescribed OAC therapy are often also treated with additional antiplatelet drugs, even when they do not have vascular disease. These findings suggest that patients receiving OAC and antiplatelet therapy should be carefully evaluated to determine whether these combinations are indicated.
- © 2012 by American Heart Association, Inc.