Recently approved blood-thinner apixaban is more effective than aspirin at reducing stroke and systemic embolism risk in patients with atrial fibrillation, regardless of whether they have previously had a stroke, a new sub-analysis shows.
Researchers looked at a large international trial which showed that for people with atrial fibrillation who are not suitable for vitamin K antagonist (VKA) treatment, apixaban cut stroke and systemic embolism risk by over half, compared with aspirin. They identified around 760 trial patients with previous stroke or TIA to determine whether this subgroup would experience greater benefit from apixaban.
Reporting in The Lancet Neurology, the authors found that with a mean follow-up of just over a year, there were 10 stroke or systemic embolism events among patients in this subgroup randomised to apixaban, compared with 33 events for those randomised to aspirin. Within the subgroup, 6.4 strokes or systemic embolic events were prevented per 100 patients treated for one year on apixaban versus aspirin. No significant increase in major bleeding was reported. Overall, the results were similar to those for the trial as a whole, said the authors.
The investigators concluded that 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. They also suggested that “the absolute benefit of apixaban over aspirin might be enhanced in secondary stroke prevention.”
Several authors disclosed ties to pharma companies Pfizer and Bristol-Myers Squibb, which jointly developed apixaban.