Warfarin, a commonly used drug for the treatment of atrial fibrillation, has been shown in new research to be associated with an increased risk of dementia. according to medicalnewstoday.com.

Atrial fibrillation (AF) is an irregular heartbeat, typically fast, that can lead to shortness of breath, dizziness, and tiredness, among other symptoms, and increases a person’s risk of stroke five times.  The condition is often treated by prescribing a blood-thinning drug, Warfarin.

With the population aging, AF is becoming more common and the use of the drug, which has been available for about 50 years, is on the rise as well.  It is estimated some 20 million Americans are taking the medication, which has saved countless numbers of lives over the years.

The new study used data from over 10,000 patients who were long-term users of the drug, either for AF or other conditions, including thromboembolism and valvular heart disease.  None of the patients in the study had any history of dementia.

The study looked at the records of the patients after a seven-year period, and found that dementia was more prevalent in 5.8 percent of the AF group, compared to 1.6 percent of the non-AF subjects.

According to Dr. T. Jared Bunch and a team of researchers from Intermountain Medical Center Hearl Institute in Salt Lake City, Utah, those taking warfarin for AF had an increased rate of vascular dementia when compared to those taking the drug for other conditions.

Warfarin has been known to be a difficult drug to manage properly, due to the fine line between clotting and bleeding.  It seems each patient responds to the drug in a different manner, and in many cases, it may take a long period of time to get the dosage correct.

Previous research as shown that AF patients who have trouble managing the dosage of warfarin might have an increased risk of dementia, and the new research seems to suggest those findings are correct.  But, the new study says even those who have been able to manage the drug are still at an increased risk.

Dr. Bunch said he thought this new information was of great importance and he recommended only those who absolutely need blood thinners should have the drugs prescribed for them.

The findings from the study were presented at the Heart Rhythm Society’s 37th Annual Scientific Sessions.