Aspirin vs. Warfarin for Deep Vein Clots
But heart experts say it's not a preferred or ideal choice
By Steven Reinberg
TUESDAY, Aug. 26, 2014 (HealthDay News) -- Aspirin may offer an alternative for people who've had blood clots in the deep veins of the legs and can't tolerate long-term use of blood thinners, according to Australian researchers.
The condition, called deep vein thrombosis (DVT), can be life-threatening if clots break loose, travel to the lungs and block a pulmonary artery. Patients are usually prescribed blood thinners such as warfarin to prevent clot formation, the researchers noted.
"Most people who have had a blood clot in a leg vein or an embolism where the clot blocks the blood flow have anticoagulant drug treatment, such as warfarin, for at least six months, first to dissolve the clot and then to prevent it happening again," said lead researcher Dr. John Simes, a professor of medicine at the University of Sydney.
However, long-term use of warfarin (Coumadin) can be inconvenient, requiring frequent blood tests and dosage adjustments, he said.
Newer drugs, such as Pradaxa (dabigatran) and Xarelto (rivaroxaban), are effective and don't require frequent blood tests. However, they're expensive, and some patients can't tolerate them, Simes said.
"Further, there is an elevated risk that the treatment can cause bleeding in some patients. Consequently, many patients choose not to continue such drugs after a period of time," he said.
The study, published online Aug. 25 in the journal Circulation, shows daily aspirin reduces the risk of another clot without causing undue bleeding, compared with no treatment, Simes explained.
Specifically, a daily aspirin reduced the risk of developing blood clots by 42 percent, compared with patients taking an inactive placebo, the researchers found.
"This is especially important for patients who are not able to take long-term anticoagulant medications for whatever reason, such as personal preference, adverse effects of the anticoagulant or cost," Simes said.
Without blood thinners, patients who have had a deep vein thrombosis run a 10 percent risk of developing recurrent clots within the first year and a 5 percent risk each year after, the researchers say.
Dr. Gregg Fonarow, a professor of cardiology at the University of California, Los Angeles, and a spokesman for the American Heart Association, cautioned that patients shouldn't think they can switch over to aspirin based on this study.