In people with blood clots in the leg or certain heart rhythm problems, direct oral anticoagulants reduce deaths due to blood clots or bleeding compared with warfarin

Chai-Adisaksopha C, Hillis C, Isayama T, et al. Mortality outcomes in patients receiving direct oral anticoagulants: a systematic review and meta-analysis of randomized controlled trials. J Thromb Haemost. 2015:2012-20.

Review question

In people with blood clots in the leg or certain heart rhythm problems (mainly atrial fibrillation), do direct oral anticoagulants (one type of “blood thinner”) cause less bleeding than warfarin or other similar blood thinners?

Background

Blood clots in the legs are dangerous because clots can break off and travel within the body, blocking arteries in the lung (pulmonary embolism), causing lung damage or even death.

People with certain heart rhythm problems (e.g., atrial fibrillation) are also at risk for blood clots and stroke due to blood clots.

Anticoagulant drugs, often referred to as “blood thinners,” can prevent blood clots. These drugs can also cause serious bleeding. Some blood thinners may be better than others at preventing clots or may cause less bleeding.

How the review was done

The researchers did a systematic review, searching for studies available up to August, 2015.

They found 13 randomized controlled trials with 103,013 people.

The key features of the trials were:

• people had blood clots in the leg, a sudden blockage in a lung artery, or heart rhythm problems;
• people were treated with one type of blood thinner called direct oral anticoagulant drugs (dabigatran, rivaroxaban, apixaban, or edoxaban) for at least 3 months;
• direct oral anticoagulant drugs were compared with another type of blood thinner called warfarin (or heparin followed by warfarin); and
• outcomes were measured after 6 to 34 months.

What the researchers found

Compared with warfarin, direct oral anticoagulants reduced the proportion of people who died from blood clots, bleeding, or from any cause.

Conclusion

In people with blood clots in the leg or certain heart rhythm problems, direct oral anticoagulants reduce deaths due to blood clots, bleeding, or any cause compared with warfarin.

Direct oral anticoagulants (DOACs) vs warfarin in people with venous thromboembolism or atrial fibrillation