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Doctor, I am over the age of 75 and have atrial fibrillation. Which anticoagulant should I take to prevent stroke?

In people over 75 years old with atrial fibrillation, direct oral anticoagulants (DOACs) are more effective than warfarin at preventing stroke or systemic embolization and are less likely to cause intracranial hemorrhage. However, these studies did not include people with heart valve problems, advanced kidney disease or liver disease.

Study highlights

People taking a DOAC were 24% less likely to have a stroke or systemic embolization compared to those taking warfarin.

People taking a DOAC were 52% less likely to have an intracranial hemorrhage compared to those taking warfarin.

Major bleeding did not differ for people taking a DOAC compared with those taking warfarin.

Understanding the problem

Atrial fibrillation is an abnormal heart rhythm that results in an irregular heartbeat. It is caused by abnormal electrical conduction within the small upper chambers of the heart. As a result, blood clots can form within these chambers and travel to the brain (causing a stroke) or elsewhere in the body (causing systemic embolization). Doctors recommend that most older people with atrial fibrillation take an anticoagulant to reduce their risk of stroke or systemic embolization.

Several large randomized controlled trials have shown that DOACs are as safe and effective as warfarin, an older blood thinner, for individuals with atrial fibrillation. However, these studies did not focus specifically on older individuals, and they did not compare the efficacy and safety of individual DOACs against one another.

Researchers conducted this systematic review to understand how DOACs compare to warfarin for older people with atrial fibrillation and determine whether one specific DOAC is safer or more effective than the others.

A summary of 5 studies published up to December 12, 2018.

Who? The studies included 27,639 people over the age of 75 with atrial fibrillation not related to problems with their heart valves.

What? The studies compared DOACs with warfarin.

DOACs

vs

Warfarin

Eliquis® 2.5 mg twice a day or 5 mg twice a day

Pradaxa® 110 mg twice a day or 150 mg twice a day

Xarelto® 15 mg once a day or 20 mg once a day

Lixiana® 30 mg once a day or 60 mg once a day


Warfarin adjusted to maintain a target INR between 2 and 3




DOACs vs warfarin in people over 75 years old with atrial fibrillation (average age 79 years; 58% male)

Outcomes

Results

Number of studies and quality of the evidence

Stroke or systemic embolization

24% fewer people had stroke or systemic embolization while taking a DOAC compared to those taking warfarin.

In other words, 76 people had a stroke or systemic embolization while taking a DOAC for every 100 people who had a stroke or systemic embolization while taking warfarin.

5 studies


High-quality evidence

Intracranial hemorrhage

52% fewer people had an intracranial hemorrhage while taking a DOAC compared to those taking warfarin.

In other words, 48 people had an intracranial hemorrhage while taking a DOAC for every 100 people who had an intracranial hemorrhage while taking warfarin.

5 studies

High-quality evidence

Major bleedingNo difference in major bleeding between DOACs and warfarin.

5 studies

High-quality evidence


This Evidence Summary is based on the following article:

Malik AH, Yandrapalli S, Aronow WS, et al. Meta-Analysis of Direct-Acting Oral Anticoagulants Compared With Warfarin in Patients >75 Years of Age. Am J Cardiol. 2019 Jun 15;123(12):2051-2057. doi: 10.1016/j.amjcard.2019.02.060. Epub 2019 Mar 18. PubMed

Published: Tuesday, July 30, 2019
Last Updated: Thursday, July 30, 2020