• Posted November 19, 2024

Adding Blood Thinners to A-fib Treatment Won't Prevent Strokes, Help Cognition

People using blood thinners to control their heart rhythm shouldn't expect the medications to head off thinking declines as well, new research suggests.

The study, presented Saturday at a meeting of the American Heart Association in Chicago, is the first large trial to investigate whether anti-clotting medication can lower the risk of mental decline, stroke or mini-stroke in adults with atrial fibrillation (A-fib). 

A-fib is an irregular heartbeat that can lead to serious issues, including heart failure and stroke. It has also been linked to mental decline.

"Although numerous observational studies have reported an association between A-fib and cognitive decline, we found that anticoagulation therapy initiated in relatively younger adults with A-fib did not reduce this risk," said study leader Dr. Lena Rivard, an associate professor of medicine at the University of Montreal. 

"Patients should adhere to standard recommendations for cognitive health, including adopting a healthy lifestyle, engaging in activities that stimulate their brains and maintaining regular physical activity," she added in a meeting news release.

For the study, her team investigated the anti-clotting medication rivaroxaban. It's often prescribed to patients over 65 who are at risk for stroke. Those patients include folks who have had a previous stroke, mini-stroke, high blood pressure, diabetes or heart failure.

The new study, which included more than 1,200 adults, confirms that the risk of stroke in younger patients with A-fib is small. It also supports current treatment guidelines.

Researchers had planned to follow participants, on average, for up to five years. But the study was ended after about 3-1/2 years, because the lack of cognitive benefit from the medication was clear.

On average, participants were 53 years of age. They had A-fib but none of the standard risk factors that would require a blood thinner.

Half received 15 milligrams (mg) of rivaroxaban daily, the others received a placebo. They had annual tests of thinking skills and were monitored for stroke or transient ischemic attacks (TIAs), also known as mini-strokes. 

After an average of almost four years, 20% experienced mental decline, stroke or TIAs. 

Cognitive decline accounted for 91% of this outcome. It was measured on a standard test called the Montreal Cognitive Assessment, and cognitive decline was considered significant if there was a drop of 2 points or more.

One in 200 participants had major bleeding and fewer than 1 in 100 (0.8%) had a stroke each year.

Outcomes were no different between those taking rivoroxaban and the placebo.

"In clinical practice, people younger than age 65 with A-fib tend to be over-treated with anticoagulant therapy, while older people who have indications for anticoagulation are under-treated," Rivard said in a meeting news release.

"Our study supports current guidelines by confirming that younger people with A-fib but no other risk factors for stroke have a low rate of stroke, and anticoagulation is not useful in reducing the risk of cognitive decline," she added.

Research presented at meetings is considered preliminary until published in a peer-reviewed journal.

More information

There's more about atrial fibrillation at the Cleveland Clinic.

SOURCE: American Heart Association, news release, Nov. 16, 2024