(HealthDay News) – Apixaban is more effective than aspirin in reducing the risk of repeat stroke and systemic embolism in patients with atrial fibrillation (AF) who are unsuitable for vitamin K antagonists (VKA) therapy, according to a study presented at the American Heart Association’s International Stroke Conference, held from Feb. 1 to 3 in New Orleans.
Hans-Christoph Diener, MD, of the University Hospital Essen in Germany, and colleagues studied 5,599 patients with AF who were randomized to receive apixaban 5mg twice daily or aspirin (81–324 mg/day). Of the participants, 764 had had a prior stroke or transient ischemic attack (TIA). Patients were followed up for a mean duration of 1.1 years.
The researchers found that, in the patients with prior TIA or stroke, among those randomized to apixaban, there were 10 stroke or systemic embolism events (2.46%/year) compared with 33 events in those randomized to aspirin (8.27%/year) (HR, 0.29; P<0.001). There were nine ischemic strokes in the apixaban group and 27 in the aspirin group (2.21%/year vs. 6.27%/year; HR, 0.33; P<0.002). One patient on apixaban and four patients on aspirin suffered a hemorrhagic stroke. Twenty-two patients on apixaban (5.30%/year) and 27 on aspirin (6.55%/year) died (HR, 0.82; P=0.5). No statistically significant differences were seen in major bleeds between the groups.
“In patients with AF who had a TIA or stroke and [were] unsuitable for VKA therapy, apixaban reduced the risk of stroke or systemic embolism to [a] larger extent than aspirin,” the authors write.
Several authors disclosed financial ties to pharmaceutical companies, including Pfizer and Bristol-Myers Squibb who jointly developed apixaban.