London: People with rheumatoid arthritis face a heightened risk of irregular heart rhythm and stroke, Danish scientists have found.
Previous research has shown links between rheumatoid arthritis and heart attacks and heart failure, but this is the first study to examine the possibility of a link with atrial fibrillation – the most common form of irregular heart rhythm and a risk factor for stroke.
Scientists at Copenhagen University Hospital, Gentofte looked at data on more than four million people in Denmark, including 18,247 who had been diagnosed with rheumatoid arthritis.
Participants were followed for approximately five years to see whether they developed atrial fibrillation or had a stroke.
Publishing their findings in the British Medical Journal, the study authors revealed that people with rheumatoid arthritis were 40 per cent more likely to develop atrial fibrillation than people without the autoimmune disease.
This means there would be one new case of atrial fibrillation per 12 patients followed for ten years after their diagnosis.
In addition, people with rheumatoid arthritis had a 30 per cent increased risk of stroke compared with the general population.
The researchers noted: “For both atrial fibrillation and stroke, we saw remarkable threefold increases in the relative risks in patients with rheumatoid arthritis younger than 50, as also indicated by the high proportion of the risk that was attributable to rheumatoid arthritis in young compared with older patients.
“Nonetheless, the absolute differences in rates of atrial fibrillation and stroke between people with and without rheumatoid arthritis were highest in the oldest patients.”
They concluded: “The augmented risk of stroke in rheumatoid arthritis adds significantly to existing evidence, and the novel finding of an increased incidence of atrial fibrillation suggests that this arrhythmia is relevant in cardiovascular risk assessment of these patients.”
A spokesman for Arthritis Research UK said that the link between rheumatoid arthritis and atrial fibrillation was not previously known and was of interest to clinicians, although not surprising.
He added: “Inflammation plays a central role in rheumatoid arthritis and in the disease process of many other related conditions, so it’s not surprising that it may also play a role in the development of atrial fibrillation.”