New blood thinner better at preventing recurrent blood clots than aspirin

March 18, 2017

An international research team with prominent Canadian leadership has found that the blood thinner rivaroxaban is as safe as aspirin, and more effective at preventing recurrence of life-threatening blood clots in the legs and lungs, according to a study published in the New England Journal of Medicine.

At least one out of 1,000 Canadians will experience one of these blood clots every year, a condition called venous thromboembolism. The clots can be deadly if they travel to the lungs (pulmonary embolism), and are the third most common cardiovascular cause of death after heart attack and stroke.

Venous thromboembolism is a chronic disease, with risks of additional blood clots over a patient's lifetime. However, many physicians and patients are deciding against long-term treatment with blood thinners because of concern about the risk of bleeding. Some are choosing aspirin instead because they consider it to be safer.

The large international study of 3,396 patients with venous thromboembolism in 31 countries shows, however, that rivaroxaban is more effective than aspirin.

"Not only that, but in testing two doses of rivaroxaban, we found that we have the option of lowering the daily dose for extended treatment," said Dr. Jeffrey Weitz, principal investigator of the study and professor of medicine and biochemistry and biomedical sciences at the Michael G. DeGroote School of Medicine at McMaster University. "This will ease the long-term concerns of both patients and their doctors."

During the study from March 2014 to March 2016, patients received either a daily 20mg dose of rivaroxaban, a 10mg dose of rivaroxaban, or a 100 mg dose of aspirin. They took these medications for up to 12 months after they had received treatment for their initial clot.

The researchers found that patients taking aspirin had the highest rate of recurrent blood clots, at 4.4 percent. The rates of recurrent clots for patients taking 20mg and 10mg of rivaroxaban were significantly lower, at 1.5 and 1.2 percent respectively.

When they looked at bleeding side-effects, there were no statistically significant differences between the treatments. The rates of major bleeding were 0.3 percent in the group taking aspirin, and 0.5 percent and a 0.4 percent in the groups taking 20 mg and 10mg of rivaroxaban, respectively.

Dr. Philip Wells, head of the Department of Medicine and senior scientist at The Ottawa Hospital and the University of Ottawa and an author of the study, will present the research at the American College of Cardiology's 66th Annual Scientific Session today.

"We know from previous studies that only about 40 percent of venous thromboembolism patients are actually on long-term blood thinners," said Wells.

"We hope that this study, which shows the blood thinner rivaroxaban, is as safe as aspirin but much more effective at preventing future clots, will convince patients and their physicians to continue life-long medication that can prevent potentially dangerous blood clots."

Rivaroxaban is a prescription drug available in Canada for about $100 a month, and most private insurance plans will cover the cost. Aspirin costs pennies a day and is available over the counter.
-end-
The study was funded by Bayer AG.

Full reference: Rivaroxaban or Aspirin for Extended Treatment of Venous Thromboembolism. Jeffrey I. Weitz, Anthonie W.A. Lensing, Martin Prins, Rupert Bauersachs, Jan Beyer-Westendorf, Henri Bounameaux, Timothy A. Brighton, Alexander T. Cohen, Bruce L. Davidson, Hervé Decousus, Maria Cecilia S. Freitas, Gerlind Holberg, Ajay Kakkar, Lloyd Haskell, Bonno van Bellen, Akos F. Pap, Scott D. Berkowitz, Peter Verhamme, Philip S. Wells, Paolo Prandoni, on behalf of the EINSTEIN CHOICE Investigators. The New England Journal of Medicine. March 18, 2017

Media Contacts:

Veronica McGuire, Media Relations Co-ordinator, Faculty of Health Sciences, McMaster University; vmguir@mcmaster.ca; Office: 905-525-9140 x 22169; Cell: 289-776-6952

Amelia Buchanan, Senior Communication Specialist, Ottawa Hospital Research Institute; ambuchanan@ohri.ca; Office: 613-798-5555 x 73687; Cell: 613-297-8315

McMaster University

Related Aspirin Articles from Brightsurf:

An aspirin a day keeps the bowel doctor away
A regular dose of aspirin to reduce the risk of inherited bowel cancer lasts at least 10 years after stopping treatment, research has revealed.

What are the risks and benefits of low-dose aspirin?
Low-dose aspirin significantly lowers cardiovascular disease risk but increases the risk of bleeding, according to a review published in the British Journal of Clinical Pharmacology.

Benefit seen for ticagrelor alone, without aspirin, in patients with ACS
The research was presented at the American College of Cardiology's Annual Scientific Session Together with World Congress of Cardiology (ACC.20/WCC).

Study: An aspirin a day does not keep dementia at bay
Taking a low-dose aspirin once a day does not reduce the risk of thinking and memory problems caused by mild cognitive impairment or probable Alzheimer's disease, nor does it slow the rate of cognitive decline, according to a large study published in the March 25, 2020, online issue of Neurology®, the medical journal of the American Academy of Neurology.

Aspirin's health benefits under scrutiny
Taking a baby aspirin every day to prevent a heart attack or stroke should no longer be recommended to patients who haven't already experienced one of these events.

Aspirin may no longer be effective as cardiovascular treatment
A new paper in Family Practice, published by Oxford University Press, found that the widespread use of statins and cancer screening technology may have altered the benefits of aspirin use.

Migraine headaches? Consider aspirin for treatment and prevention
Evidence from 13 randomized trials of the treatment of migraine in 4,222 patients and tens of thousands of patients in prevention of recurrent attacks supports the use of high dose aspirin from 900 to 1,300 milligrams to treat acute migraine as well as low dose daily aspirin from 81 to 325 milligrams to prevent recurrent attacks.

Aspirin use after biliary tract cancer diagnosis
Researchers in this observational study examined if aspirin use after a diagnosis of a biliary tract cancer, which includes gallbladder cancer, was associated with reduced risk of death among nearly 3,000 patients.

Aspirin may prevent air pollution harms
A new study is the first to report evidence that nonsteroidal anti-inflammatory drugs (NSAIDs) like aspirin may lessen the adverse effects of air pollution exposure on lung function.

Aspirin should not be recommended for healthy people over 70
Low-dose aspirin does not prolong disability-free survival of healthy people over 70, even in those at the highest risk of cardiovascular disease.

Read More: Aspirin News and Aspirin Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.