October 28, 2008
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.
But rheumatoid arthritis also seems to have another effect. People with RA are at increased risk for heart failure and death due to heart disease.
What is less clear, however, are the factors that lead to heart failure in these patients, how to find it sooner, and how to possibly prevent it. Recent research has focused on diastolic dysfunction, a condition in which the ventricles of the heart become relatively stiff leading to impaired filling. Over time, this can lead to heart failure.
Researchers recently compared the frequency of diastolic dysfunction in 149 people with RA to a group of 1,405 people without the disease. They conducted a community-based prospective study of adult patients with and without RA living in Olmsted County, Minn., who had no history of heart failure. Participants in both groups completed a questionnaire and had echocardiograms (cardiac ultrasounds), which were interpreted by the same study team to ensure comparability between participants.
Researchers found that diastolic dysfunction was more common in the patients with RA, occurring in 38.9 percent; compared to 28.8 percent in the non-RA group. They also found that patients in the RA group had higher average pulmonary arterial pressure, which is high blood pressure in the lungs and the right side of the heart.
"Wider use of echocardiography in patients with RA may reveal heart abnormalities before they are detected clinically," said Kimberly Liang, MD; assistant professor, University of Pittsburgh, Pittsburgh, Pa., and lead author of the study. "Early detection could improve long-term outcomes in these patients."
Following a heart attack, people with rheumatoid arthritis suffer greater heart-related complications, including an increased risk for dying, when compared to other heart attack patients, according to research presented this week at the American College of Rheumatology Annual Scientific Meeting in San Francisco.
Researchers recently followed 38 heart attack patients who had RA to compare their mortality rates to those patients who had suffered a heart attack but did not have RA. Most patients were female, with a mean age of 76 years.
Patients with RA were hospitalized for their first heart attack between 1976 and 2001. Researchers evaluated treatment of heart attacks and tracked patient outcomes (heart failure and death). Diagnosis of heart attack and heart failure were validated using established epidemiological criteria, and rates of heart failure and death following heart attacks in the general population were based on previously published rates during the same years.
Of the 38 RA patients in the study, nine had experienced heart failure prior to the heart attack; of the remainder, a total of 18 RA patients developed heart failure following their heart attacks making the risk of heart failure following a heart attack in patients with RA 45 percent higher than expected in the general population. The risk of death was noted to be 75 percent higher in heart attack patients with RA, and was particularly high among patients with rheumatoid arthritis who had a positive blood test for rheumatoid factor.
In all, researchers determined that patients with RA do suffer higher mortality and may be at higher risk of heart failure after a heart attack, but reasons for these outcomes are still unknown. The results of this study emphasize the need for better strategies for prevention, diagnosis and treatment of heart attacks in these patients.
"Heart disease can remain silent in those with rheumatoid arthritis, but the risk is there soon after the onset of the disease" said Hilal Maradit Kremers, MD; Mayo Clinic epidemiologist and lead author of the study. "Regular cardiac checkups are importantas is lowering traditional cardiac risk factors, such as taking care of blood pressure and cholesterol and quitting smoking."
