Heart rhythm disorder, Alzheimer's linked

BOSTON, May 20 (UPI) -- U.S. researchers say they have linked a heart rhythm disorder -- atrial fibrillation -- and Alzheimer's disease.

Lead researcher Dr. T. Jared Bunch says patients with atrial fibrillation were 44 percent more likely than those without atrial fibrillation to develop dementia.

Younger atrial fibrillation patients -- under age 70 -- were 130 percent more likely to develop the form of dementia known as Alzheimer's disease. The younger atrial fibrillation patients with dementia were more likely to die than the older patients with both disorders.

The Intermountain Medical Center in Salt Lake City researchers studying five years of patient records for 37,025 people -- taken from the Intermountain Heart Collaborative Study database of hundreds of thousands -- found 10,161 patients had atrial fibrillation and 1,535 had dementia.

"Previous studies have shown that patients with atrial fibrillation are at higher risk for some types of dementia, including vascular dementia, but to our knowledge, this is the first large-population study to clearly show that having atrial fibrillation puts patients at greater risk for developing Alzheimer's disease," study lead researcher Dr. T. Jared Bunch said in a statement. "The Alzheimer's findings -- particularly the risk of death for younger patients -- break new ground."

Bunch presented the findings at the annual scientific sessions of the Heart Rhythm Society in Boston.