Patients with atrial fibrillation who take Warfarin may face a higher risk of developing dementia and Alzheimer’s disease. This is the first time that long-term use of anticoagulation drugs, has been linked to cognitive risk. Detailed results of the research were presented Thursday, at Heart Rhythm in San Francisco.

Warfarin is an oral drug used to prevent the formation and expansion of blood clots, in the blood vessels, according to MedlinePlus from the U.S. National Library of Medicine. It is usually prescribed for people who had a heart attack, and people with certain types of irregular heartbeat, or a mechanical heart valve.

Photo credit: Divers Alert Network
Patients with atrial fibrillation who take Warfarin may face a higher risk of developing dementia and Alzheimer’s disease. Photo credit: Divers Alert Network

The study shows that patients with atrial fibrillation, who underwent to long-term treatments of Warfarin, had higher rates of dementia, Alzheimer’s disease, and vascular dementia. Results were compared to rates of patients without atrial fibrillation, who took the same medicine, said study authors at the Intermountain Medical Center Heart Institute.

Atrial fibrillation is the most common type of heart arrhythmia, which is when the heart beats at a different rate than normal. There are an estimated 2.7-6.1 million people in the United States with the heart condition, said the Centers for Disease Control and Prevention (CDC).

Incidence rates of Atrial fibrillation are increasing “dramatically” in the country, as the population gets older. Symptoms of the condition include irregular heartbeat, heart palpitations, lightheadedness, extreme fatigue and chest pain, added the CDC.

Study details and other theories on atrial fibrillation

Researchers at the Intermountain Medical Center Heart Institute analyzed data from 10,537 patients without previous history of dementia. All participants were treated with the blood thinner Warfarin. Patients under 70 years were the most susceptible to developing dementia.

Patients with atrial fibrillation tend to face higher rates of dementia, regardless of the use of anticoagulation. A theory proposes that the efficacy of Warfarin may be associated with the neurological disorder, which impairs memory, said researchers in a press release issued Thursday.

“Our study results are the first to show that there are significant cognitive risk factors for patients treated with Warfarin over a long period of time regardless of the indication for anticoagulation,” said lead author T. Jared Bunch, director of heart rhythm research at Intermountain Medical Center Heart Institute.

Blood clots caused by atrial fibrillation can interfere in the brain function, which at the same time can lead to an increased risk of developing dementia.  Blood thinners such as Warfarin may also affect brain function in the long term.

“As physicians we have to understand that although we need to use anticoagulants for many reasons including to prevent stroke in AF patients, at that same time there are risks that need to be considered some of which we are only right now beginning to understand,” said Bunch, M.D., in a press release.

Bunch concluded that the long-term use of blood thinners should be only recommended to patients in absolute need. He added that combination drugs like aspirin, which enhance the effect of blood thinners, should be avoided.

Source: Intermountain Medical Center Heart Institute Press Release