Alzheimer's Risk Increases With Common Heart Rhythm Problems
A large study of 37,000 people shows that the common heart rhythm problem atrial fibrillation increases risk of dementia from Alzheimer’s disease. Data extracted from the Intermountain Heart Collaborative Study, presented May 15, at "Heart Rhythm 2009," the annual scientific sessions of the Heart Rhythm Society in Boston, shows that patients with atrial fibrillation, especially young people, have a significant risk of developing Alzheimer’s disease, a leading cause of dementia in the United States.
Atrial fibrillation occurs when electrical signals in the heart become disrupted, causing the upper two chambers of the heart to beat less effectively. Atrial fibrillation affects approximately 2.2 million Americans according to the American Heart Association, and is now associated with a significant risk for
Alzheimer’s disease, especially if left untreated.
The risk of developing the common heart rhythm problem increases with age. Binge drinking in young people can cause atrial fibrillation. Other known causes include heart disease, heart surgery, high blood pressure, heart attack, lung disease, and sleep apnea. The irregular heart rhythm can cause stroke from blood clots that form in the heart chambers because of decreased force of contraction. John Day, M.D., director of heart rhythm services at Intermountain Medical Center and a co-author of the study says, "Now that we've established this link, our focus will be to see if early treatment of atrial fibrillation can prevent dementia or the development of Alzheimer's disease."
The results showed that atrial fibrillation increases the chances of developing Alzheimer’s disease by forty – four percent. Death risk increases by sixty-one percent for patients diagnosed with dementia, combined with atrial fibrillation.
Additional findings point to an even greater chance of Alzheimer’s disease in younger people with atrial fibrillation. The risk increased to 130 percent if atrial fibrillation develops before age seventy.
Researchers have suspected that a healthy heart can reduce the risk of developing Alzheimer’s disease. T. Jared Bunch, M.D., lead researcher for the study says, "Previous studies have shown that patients with atrial fibrillation are at higher risk for some types of dementia, including vascular dementia…this is the first large-population study to clearly show that having atrial fibrillation puts patients at greater risk for developing Alzheimer's disease."
The researchers believe that uncovering such a strong connection between atrial fibrillation and dementia is a breakthrough in understanding a significant risk factor for Alzheimer’s disease, the sixth leading cause of death in the United States.