Signs of atrial fibrillation include fluttering of the heart, dizziness, sweating, fatigue, confusion, weakness, shortness of breath and anxiety, although some patients display no symptoms. Many drugs are used to treat it, including the anticoagulant warfarin, which can reduce the risk of death by 68 percent for those with the illness, according to the heart association.
The study findings were slated to be presented Friday in San Francisco at the Heart Rhythm Society meeting.
The study, taking information from a large national database, looked at 416,786 patients older than 65, who were discharged from 1,200 hospitals around the United States after treatment for atrial fibrillation. The study controlled for factors such as age, sex, demographic information, and other illnesses.
In an initial analysis, 2.73 percent of patients with rheumatoid arthritis or lupus were found to have atrial fibrillation, compared to 1.7 percent for those unaffected by either condition.
After adjusting for confounding factors, the researchers found frequency of the heart arrhythmia was 1.6 times higher in patients diagnosed with one of the autoimmune conditions, an increased risk of 60 percent.
While the study found an association between the two diseases and the heart condition, it did not prove a cause-and-effect. And because it was presented at a medical meeting, its findings should be considered preliminary until published in a peer-reviewed journal.
Both lupus and rheumatoid arthritis are genetically based but are believed to have environmental triggers, according to Dr. Olivia Ghaw, a rheumatologist at Mount Sinai Medical Center in New York City. Women are far more likely to be affected, with estrogen playing a possible role, but no definitive answers have been found, she said.
Ghaw said that because the two autoimmune diseases "are systemic," potentially
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