Treatment for Irregular Heartbeat May Raise Dementia Risk

Overtreatment with warfarin and antiplatelets tied to raised dementia risk in atrial fibrillation patients

/ Author:  / Reviewed by: Robert Carlson, M.D Beth Bolt, RPh

(RxWiki News) For people with irregular heartbeats, the anti-clotting medication warfarin can prevent strokes. But, combined with other medications over a long period of time, it may cause other health problems.

A new study looked at the effects of long-term treatment for patients with irregular heartbeats. The patients were being treated with warfarin (brand name Coumadin), an anti-clotting medication, and an anti-platelet medication, such as aspirin. This common combination is often used to prevent blood clots that may lead to stroke, which sometimes results from an irregular heartbeat.

The study authors found that some of patients who took the combination of medications had an increased risk of dementia. The people who had an increased risk were those with an excessively long clotting times.

These patients’ blood clotted very slowly, which could cause a “negative impact on cognitive ability” due to very small brain bleeds, said lead study author T. Jared Bunch, MD, of the Intermountain Medical Center Heart Institute in Salt Lake City, UT.

Patients with irregular heartbeats, or atrial fibrillation, already face an increased risk of dementia, the authors noted.

Dr. Bunch and team studied the effects of the combination of warfarin and anti-platelets in 1,031 patients with no history of stroke or dementia. They measured how long it took for the patients’ blood to clot in monitoring tests.

According to the authors, the patients with long clotting times more than 25 percent of the time had received more medication than necessary.

Those patients were much more likely to develop dementia than patients who had long clotting times only 10 percent of the time.

Overtreatment may increase bleeding risk, which would lead to “micro bleeds in the brain that don’t cause symptoms right away, but accumulate over time raising the risk of dementia,” Dr. Bunch said in a press statement.

Dr. Bunch suggested that patients with frequently long clotting times should talk to their doctor about a treatment other than the combination of warfarin and anti-platelets to prevent blood clots.

This research was presented Nov. 16 at the American Heart Association Scientific Sessions in Chicago.

The authors did not disclose any funding sources or conflicts of interest.

Review Date: 
November 14, 2014
Last Updated:
November 19, 2014