In a recent study led by University College London (UCL) researchers, a large-scale comparison of direct oral anticoagulants (blood thinners) commonly recommended for irregular heartbeats has revealed the medication with the lowest risk of bleeding.
According to the study published in the journal Annals of Internal Medicine, apixaban, one of the two most popular direct oral anticoagulants (DOACs), has the lowest risk of gastrointestinal bleeding and performs similarly to other DOACs in terms of preventing strokes and other side effects.
Over 33 million individuals worldwide suffer from atrial fibrillation, which causes slow or irregular heartbeats; DOACs are used to prevent strokes in these patients. Compared to warfarin, the former standard of treatment, they are now more widely used because they require less follow-up monitoring (which was especially helpful during the Covid-19 outbreak) and have a lower risk of side effects.
The new study evaluated the efficacy and risk of adverse effects of the four most commonly used DOACs. They examined data from almost 500,000 new DOAC users in the United Kingdom, France, Germany, and the United States, including 281,320 apixaban users, 61,008 dabigatran users, 12,722 edoxaban users, and 172,176 rivaroxaban users.
They found that all four drugs were comparable in outcomes for ischemic stroke, brain bleeds, and all-cause mortality. At the same time, they did identify a difference in the risk of gastrointestinal bleeding, which is one of the most common and concerning side effects of DOACs.
The study revealed that apixaban stood out as having a lower risk of gastrointestinal bleeding, with 19-28% lower risks when compared directly to each of the other three DOACs.
The researchers found that their findings held true when looking at data only from those aged over 80, and those with chronic kidney disease, two groups that are often underrepresented in clinical trials.
Co-lead author Dr. Wallis Lau (UCL School of Pharmacy) said: “Direct oral anticoagulants have been prescribed with increasing frequency worldwide in recent years, but evidence comparing them directly has been limited. Our results indicate that apixaban may be preferable to other blood thinners because of the lower rate of gastrointestinal bleeding and similar rates of stroke, a finding that we hope will be supported by randomized controlled trials.”
She concludes, “As with all medications, potential risks and benefits can differ between people, so considering the full spectrum of outcomes and side effects will still be necessary for each individual patient.”
Reference: “Comparative Effectiveness and Safety Between Apixaban, Dabigatran, Edoxaban, and Rivaroxaban Among Patients With Atrial Fibrillation” by Wallis C.Y. Lau, Ph.D., Carmen Olga Torre, MSc, Kenneth K.C. Man, Ph.D., Henry Morgan Stewart, Ph.D., Sarah Seager, BA, Mui Van Zandt, BSc, Christian Reich, MD, Jing Li, MS, Jack Brewster, Ph.D., Gregory Y.H. Lip, MD, Aroon D. Hingorani, Ph.D., Li Wei, Ph.D. and Ian C.K. Wong, Ph.D., November 2022, Annals of Internal Medicine.