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Got It, Hide thisBai Y, Guo SD, Deng H, et al. Effectiveness and safety of oral anticoagulants in older patients with atrial fibrillation: a systematic review and meta-regression analysis. Age Ageing. 2017;8:1-9.
In older people with atrial fibrillation, how effective and safe is the blood thinner warfarin compared with no treatment or using other new anticoagulant pills (blood thinners)?
Atrial fibrillation is an abnormal heart rhythm that can cause small clots to form in the heart. These clots can travel to the brain causing a stroke, or they can travel to arteries in the legs, arms, or abdomen causing a systemic embolism. Doctors may prescribe anticoagulant pills (blood thinners) to reduce the formation of blood clots. Warfarin is the anticoagulant pill prescribed most often. It needs careful monitoring by doctors with frequent blood tests, and it can cause serious bleeding. Newer anticoagulant pills that don’t need frequent blood tests are also available, but not much research has been done on these pills in people older than 65 years of age.
The researchers did a systematic review, searching for studies published in English up to December 2016. They found 26 studies with people 65 years or older. 16 studies were randomized controlled trials, and 10 were observational studies.
People in the studies had atrial fibrillation.
Warfarin was compared with aspirin or no treatment in 10 of the studies.
Warfarin was compared with new anticoagulant pills in 16 of the studies. New anticoagulant pills included dabigatran, rivaroxaban, apixaban, and edoxaban.
Outcomes were stroke or systemic thromboembolism and serious bleeding.
Warfarin reduced rates of stroke/systemic thromboembolism and did not affect serious bleeding compared with aspirin or no treatment.
The risk for stroke/systemic thromboembolism was lower with new anticoagulant pills compared with warfarin.
The risk for serious bleeding was lower with new anticoagulant pills compared with warfarin. However, there were differences in this result between the studies, which means this statement may not be true for everyone.
Not all people can take the new anticoagulant pills, and they are more expensive than warfarin.
In people 65 years of age and older with atrial fibrillation, warfarin is better than no treatment for reducing strokes/systemic thromboembolism, but the new anticoagulant pills are better than warfarin at reducing these events and cause fewer serious bleeds.
Outcomes | Number of studies | Comparison groups | Effect of warfarin at 4 months to 5 years |
Stroke/systemic thromboembolism | 8 studies | Warfarin vs no treatment* | Warfarin reduced stroke/systemic thromboembolism |
Serious bleeding | 7 studies | Warfarin vs no treatment* | No differences between groups |
Stroke/systemic thromboembolism | 4 randomized controlled trials | Warfarin vs new anticoagulants | New anticoagulants reduced strokes/systemic thromboembolism |
Serious bleeding | 4 randomized controlled trials | Warfarin vs new anticoagulants | New anticoagulants reduced serious bleeding |