THURSDAY, March 8 (HealthDay News) -- People with rheumatoid arthritis (RA) are at increased risk for a heart rhythm disorder called atrial fibrillation, a new study finds.

The research involved more than 4 million people, including more than 18,000 with RA, in Denmark, who were followed for an average of five years.

During that time, people with RA had a nearly 40 percent increased risk of atrial fibrillation compared to those in the general population -- 8.2 events per 1,000 person years for those with RA and six events per 1,000 person years for the general population. That works out to one new case of atrial fibrillation per 12 RA patients followed for 10 years after diagnosis.

Among RA patients, women had a slightly higher risk of atrial fibrillation than men, according to the study published online March 8 on BMJ.

The researchers also found that people with RA had a more than 30 percent higher risk of stroke than those in the general population -- 7.6 events per 1,000 person years for those with RA and 5.7 events per 1,000 person years for the general population.

Previous research has linked RA to an increased risk of heart attacks, heart failure and stroke. This study finds that RA is also associated with an increased risk of atrial fibrillation, which is associated with greater long-term risk of heart failure, stroke and death.

New guidelines recommend that patients with RA should undergo annual screening for cardiovascular risk factors, and this should include screening for atrial fibrillation, the researchers from Copenhagen University Hospital Gentofte said in a journal release.

The researchers also noted that since inflammation plays a role in the development of atrial fibrillation and stroke, inflammation control is important for people with RA not only to alleviate joint symptoms, but also to reduce the need for drugs that may adversely impact heart health.

More information

The U.S. National Heart, Lung and Blood Institute has more about atrial fibrillation.