According to research presented this week at the American College of Rheumatology Annual Scientific Meeting in Chicago, patients with rheumatoid arthritis who have low levels of inflammatory disease activity have lower risk for heart complications and stroke.
Rheumatoid arthritis is a chronic disease that causes pain, stiffness, swelling, and limitation in the motion and function of multiple joints. Though joints are the principal body parts affected by RA, inflammation can develop in other organs as well. An estimated 1.3 million Americans have RA, and the disease typically affects women twice as often as men.
Chronic inflammation caused by RA has been linked to heart disease and stroke. Previous studies have shown the amount of time a person has RA as a more important risk factor than the inflammation that accompanies it. Researchers from the Radboud University Nijmegen Medical Centre in the Netherlands recently investigated the relationship between the years of inflammation and the risk of heart disease and stroke in people with RA.
"Identifying risk factors that accurately predict cardiovascular disease in RA is important for effective prevention in these patients. In addition to traditional risk factors such as smoking and high cholesterol levels, inflammation seems to be an important cause of cardiovascular disease in RA," says Elke.E.A. Arts, MSc; junior research associate in the Department of Rheumatology at Radboud University Nijmegen Medical Centre in the Netherlands and lead investigator of the study.
Dr. Arts also adds, "generally, the inflammatory response is a useful feature of our immune system, protecting the body from harmful stimuli such as an infection and initiating the healing process. However, RA patients are exposed to ongoing, chronic systemic inflammation, which may be destructive rather than beneficial. Although inflammation has been linked to atherosclerosis, the dynamics of the relationship between inflammatory activity in RA and the development of actual cardiovascular disease in RA requires further research. As the level of disease activity does not appear to contribute to the excess risk of CVD in RA, the time a patient is exposed to inflammation or disease duration, may be of importance."
Eight-hundred-fifty-five RA patients without a history of heart disease or stroke were included in the study, and scored to show the amount of disease activity each person was experiencing over time. Among the 855 patients, the average age was 54 years old − of which 66 percent were female, and 76 percent tested positive for rheumatoid arthritis through a blood test.
Of all participants, a total of 6,388 years of data was collected, and the researchers analyzed the relationship between years of inflammation and the occurrence of stroke and heart disease. Next, the researchers estimated the probability of developing heart disease within the first 10 years of being diagnosed with rheumatoid arthritis and compared this to the risk after more than 10 years of RA disease.
During the six month study, 91 heart and stroke complications were recorded, including heart attack, stroke and heart failure. The researchers noted the duration of disease or the level of disease activity did not correlate with the risk of heart attack or stroke. However the researchers noted a lower risk of these complications in participants with very low disease activity - meaning, they had either mild or very well controlled RA.
Dr. Arts further comments, "the finding that, in RA, the level of inflammation is not associated with the occurrence of cardiovascular disease, means that a small amount of inflammation appears to be sufficient to increase the risk of CVD. Only when disease activity is so low that it is hardly present, is the risk of CVD reduced. Hence, treatment of disease activity to achieve remission is not only important to prevent joint destruction and functional losses but perhaps also to decrease the risk of cardiovascular morbidity and mortality in these patients."
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