THURSDAY, Jan. 13 (HealthDay News) -- The heart rhythm disorder atrial fibrillation is increasingly common in kidney dialysis patients and puts them at increased risk for death, researchers have found.

In a new study, investigators analyzed data from the U.S. Renal Data System and found that the prevalence of atrial fibrillation increased more than threefold between 1992 and 2006, from 3.5 percent to 10.7 percent of dialysis patients. The actual number of affected patients increased sixfold, due to the increasing number of people in the United States who require dialysis.

Among dialysis patients most likely to experience atrial fibrillation were older patients and those with other medical conditions. Whites appear to be at a higher risk than patients of other racial/ethnic groups, according to the study, which is scheduled for publication in an upcoming issue of the Journal of the American Society of Nephrology.

The researchers found that the one-year risk of death for dialysis patients with atrial fibrillation was nearly 40 percent, compared with 19 percent for patients without the heart rhythm disorder.

"Having atrial fibrillation doubled the patient's mortality [death] risk, and sadly, that excess risk did not at all decline over the 15 years of the study," study author Dr. Wolfgang C. Winkelmayer, of Stanford University School of Medicine, said in a journal news release.

"Research is sorely needed to understand potentially modifiable risk factors for atrial fibrillation in this vulnerable population," he and his colleagues concluded.

More information

The American Academy of Family Physicians has more about atrial fibrillation.