Antithrombotic in atrial fibrillation, bleeding risk
| Author : Pierre Allain
||Date : 2010-10-25
The patients with atrial fibrillation are treated by antithrombotic drugs to avoid cardio-embolic accidents. The drugs used for this purpose are the antivitamin K, warfarin, aspirin and clopidogrel, used alone or in combination.
In a paper published in Archives of Internal Medicine, September 13, 2010, Danish authors studied, from more than 80 000 patients, the risk of bleedings fatal or not, induced by the treatments.
By giving the reference value to the risk of bleeding induced by warfarin, they obtained the following results:
Warfarin = 1
Aspirin = 0.93
Clopidogrel = 1.06
Aspirin more clopidogrel = 1.66
Warfarin plus aspirin = 1.83
Warfarin plus clopidogrel = 3.08
Warfarin plus aspirin plus clopidogrel = 3.70
This study shows that in the treatment of atrial fibrillation the incidence of bleedings was approximately the same with warfarin, (INR targeted 2.5) and with aspirin or clopidogrel. This incidence was greatly increased when these drugs were combined by 2 and especially by 3.