The researchers had suspected that atrial fibrillation might be linked to connective tissue disease because conditions such as RA cause inflammation. To validate their hypothesis, they used data from the 2008 Nationwide Inpatient Sample, which contains discharge data from about 1,000 hospitals in 40 states. They looked at discharge diagnosis of RA, systemic lupus erythematosus (SLE), and atrial fibrillation, and compared 86,497 patients with primary atrial fibrillation to 100,000 randomly selected controls. The researchers found that 2.73% of patients with RA were found to have atrial fibrillation, compared with 1.7% for those without RA. They did not find as significant an association between SLE and atrial fibrillation.
According to Dr. Pisetsky, a key limitation of the study was that it looked only at hospitalized people, and “there may be more A fib in people not in the hospital.”
Sue Pondrom is a medical journalist based in San Diego.
