Eligibility and Preference of New Oral Anticoagulants in Patients With Atrial Fibrillation
Comparison Between Patients With Versus Without Stroke
Background and Purpose—Recent randomized clinical trials (RCTs) have evaluated the benefit of new oral anticoagulants in reducing the risk of vascular events and bleeding complications in patients with atrial fibrillation (AF). However, abundant and strict enrollment criteria may limit the validity and applicability of results of RCTs to clinical practice. We estimated the eligibility for participation in RCTs of an unselected group of patients with AF. In addition, we compared features favoring new oral anticoagulant use between patients with versus without stroke. Randomized Evaluation of Long-Term Anticoagulation Therapy
Methods—We applied enrollment criteria of 4 RCTs (RE-LY, ROCKET-AF, ARISTOTLE, and ENGAGE-AF-TIMI 48) to 695 patients with AF taking warfarin, prospectively and consecutively collected at a university medical center; 500 patients with and 195 patients without stroke. Time in therapeutic range and bleeding risk scheme (anticoagulation and risk factors in atrial fibrillation) were also measured.
Results—The proportions of patients fulfilling the trial enrollment criteria varied, ranging from 39% to 72.8%, depending on the differences in indications/contraindications among studies and presence/absence of stroke. The main reasons for ineligibility for RCTs were hemorrhagic risk (anticoagulation and risk factors in atrial fibrillation [ATRIA] score) (10.8%–40.5%) and planned cardioversion (5.1%–7.7%) for nonstroke patients, and a low creatinine clearance (5.6%–9.2%) and higher risk of bleeding (15.2%–20.8%) for patients with stroke. When compared with nonstroke patients, patients with stroke showed a lower time in therapeutic range (54.4±42.8% versus 65.4±34.9%, especially with severe disability) and a high hemorrhagic risk (ATRIA score) (3.06±2.30 versus 2.18±2.16) (P<0.05 in both cases).
Conclusions—Patients enrolled in RCTs are partly representative of patients with AF in clinical practice. When time in therapeutic range and bleeding tendency with warfarin use were considered, the use of new oral anticoagulants was preferred in patients with stroke than in nonstroke patients, but they were more likely to be excluded in RCTs.
- Received March 27, 2014.
- Revision received July 23, 2014.
- Accepted July 28, 2014.
- © 2014 American Heart Association, Inc.