London, May 5 (IANS): People suffering from rheumatoid arthritis are at increased risk of heart disease and about a fourth of them are likely to have a surprise heart attack, a new research has found.

The researchers found that the risk was increased even when patients showed no symptoms and was independent of traditional cardiovascular risk factors such as smoking and diabetes.

"Our study suggests that one quarter of patients with rheumatoid arthritis and no symptoms of heart disease could have a heart attack without prior warning," said Adriana Puente, cardiologist in the National Medical Centre "20 de Noviembre" ISSSTE in Mexico City, Mexico.

The study investigated the presence of ischaemia and infarction secondary to atherosclerotic disease (coronary artery disease) in 91 patients with rheumatoid arthritis and traditional cardiovascular risk factors but no symptoms of heart disease.

Patients in the study were 90 percent women and 59 years old on an average and had a similar frequency of cardiovascular risk factors as the general population.

Inflammatory markers, rheumatoid arthritis disease activity and risk factors were measured in all patients.

"Our study shows that one quarter of patients with rheumatoid arthritis and no symptoms of heart disease do have coronary heart disease. This means they are at increased risk of cardiovascular death," Puente noted.

"Rheumatoid arthritis affects 1.6 percent of the general population and is the first cause of consultation in the rheumatology service. The condition nearly doubles the risk of a heart attack but most patients never knew they had heart disease and were never alerted about their cardiovascular risk," Puente pointed out.

The findings were presented at ICNC 12 held in Madrid, Spain.

ICNC is organised by the Nuclear Cardiology and Cardiac CT section of the European Association of Cardiovascular Imaging (EACVI).