Older adults who suffer a fall are twice as likely to have a common type of irregular heartbeat known as atrial fibrillation, according to a new study. 

“These results are certainly surprising, as an association between AF and falls has not been shown in the general population before,” said Dr. Sofie Jansen of the Academic Medical Center in Amsterdam, The Netherlands.

Certain arrhythmias are known to cause fainting or blackouts, but this is the first study to show the link with falls, Jansen told Reuters Health by email.

She and her colleagues analyzed data on 4,800 adults over age 50 in Ireland who completed questionnaires, personal interviews and physical health assessments, including electrocardiograms, between 2009 and 2011.

Twenty percent of participants reported falling at least once in the past year. Fainting and blackouts were less common.

Overall, three percent of people had atrial fibrillation (AF): about one percent of those ages 50 to 64, four percent of those up to age 74, and almost eight percent of those ages 75 and older. More than a third did not know they had AF before the study.

Almost 30 percent of those with AF had fallen over the past year compared to about 20 percent of those without AF, the researchers reported in Age and Ageing.

After accounting for other risk factors that might contribute to falls, the authors found that having AF doubled people's odds of falling.

In addition, 10 percent of people with AF reported fainting or blacking out compared to four percent of those without the arrhythmia.

At least five million U.S. adults in 2010 had been diagnosed with atrial fibrillation, which may rise to about 12 million cases by the year 2030, according to a 2013 study (see Reuters Health article of July 26, 2013 here: reut.rs/1BSOiNn).

The irregular, usually very fast, heartbeat can cause uncomfortable palpitations, limit the ability to exercise or lead to heart failure or stroke, but it may not cause symptoms for some. It can be treated with medications and lifestyle changes to reduce stroke risk, according to the National Institutes of Health.

There are several ways AF could cause a fall, Jansen said.

“AF can impair the ability of the heart to pump blood around the body, including the brain,” she said. “This can lead to a reduction in the amount of oxygen going to the brain, causing either a faint or black-out (syncope), or dizziness resulting in a fall in a person who is already unstable.”

The irregular heartbeat can also be tied to stroke and hypertension, which can lead to degenerative changes in the brain.

“All of these changes in the brain can also affect walking, mobility, and other conditions that affect fall risk, such as depression and dementia,” Jansen said.

But, she emphasized, this study did not show that AF causes falls, only that it is significantly more common among people who fall.

“Falls are very common in older adults,” Jansen said. “People with AF have an even greater risk of falls, and when they suffer from falls they should definitely mention this to their physician, as there are several treatment or prevention options for falls.”

“Because falls usually have several causes or contributing factors, recognition and treatment of all of these factors is vital to reduce fall risk,” she said.

The most common causes of falls are muscle weakness, balance problems, gait problems, medication side effects, neurological issues, dizziness or cognitive impairment, according to Dr. Laurence Z. Rubenstein, who chairs the Donald W. Reynolds Department of Geriatric Medicine at the University of Oklahoma in Oklahoma City.

Cardiac arrhythmias, including AF, do cause some falls but less commonly than the other causes and risk factors mentioned, said Rubenstein, who was not part of the new study.

“Falls are a very important problem in the older population and we’re always looking for ways to reduce them,” he said. “When you do a post-fall evaluation, listening to the heart is an important part of that,” and a doctor would likely discover signs of AF it were present, he said.