When it comes to preventing a second stroke, aspirin is just as good as dalteparin, a blood-thinning agent that prevents clotting, researchers report.
The study looked at people with atrial fibrillation, a common heart rhythm abnormality that increases the risk of stroke due to a blood clot. About 80% of strokes are due to the formation of a blood clot, which may be helped by blood-thinning drugs, while 20% of strokes are due to uncontrolled bleeding in the brain -- a condition that can be worsened by blood thinners.
It has not been clear if patients with atrial fibrillation and stroke would benefit from a class of blood-thinning drugs known as low molecular-weight heparins (LMWH), which include dalteparin.
The new study findings "provide no evidence" that high doses of LMWH are better than aspirin when it comes to preventing a second stroke or improving the patient's ability to function in the months after a stroke, according to Dr. Eivind Berge of the Ulleval University Hospital in Oslo, Norway, and colleagues.
In the study, 449 patients who had atrial fibrillation took either dalteparin or aspirin in the 30 hours after having a stroke, according to the report in the April 8th issue of The Lancet.
Overall, about 9% of dalteparin-treated patients and about 8% of aspirin-treated patients suffered from a second stroke in the 2 weeks after the first, the authors report. Bleeding within the brain -- a risk with blood-thinning drugs -- was detected in 12% of the dalteparin patients and in 14% of the aspirin patients.
There were no overall differences between the groups in the number of second strokes, worsening of symptoms and death, the researchers report, and disability at 14 days and 30 days was not different between the two groups.
The findings suggest that patients with atrial fibrillation may benefit from treatment with aspirin immediately after a stroke and possibly low dose LMWHs later on, to prevent blood clot formation elsewhere in the body.
