MONDAY, Oct. 27, 2008 (HealthDay News) -- People newly diagnosed with rheumatoid arthritis face twice the risk of a heart attack, and those who do suffer a heart attack tend to have more heart-related complications, new research says.
It seems that a condition called diastolic dysfunction, which causes the lower chambers of the heart to become stiff, is the culprit. Diastolic dysfunction impairs the ability of the ventricles to fill with blood and can lead to heart failure, the researchers said.
These are the conclusions of three reports presented at the American College of Rheumatology (ACR) annual scientific meeting, which runs from Oct. 24-29, in San Francisco.
"Rheumatoid arthritis patients not only have more heart attacks and heart failures, but they also have worse prognosis once they have a cardiovascular event," said Dr. Hilal Maradit Kremers, lead researcher on one of the studies and an epidemiologist at the Mayo Clinic in Rochester, Minn.
For the study, Kremers' team followed 38 patients with rheumatoid arthritis who had suffered a heart attack. Then they compared these patients with patients without rheumatoid arthritis who also had a heart attack.
The researchers found that the rheumatoid arthritis patients had a 45 percent greater risk of developing heart failure after a heart attack, compared with the general population, and a 75 percent greater risk of dying.
Kremers said patients with rheumatoid arthritis should take all the usual precautions to reduce their risk of a heart attack, including proper diet, exercise, no smoking and maintaining a healthy weight. "Try to avoid to get that heart attack," she said.
For the second study, Marie Gunnarsson, a doctoral student at the Institute of Environmental Medicine at the Karolinska Institute in Stockholm, Sweden, and colleagues found that the risk of heart attack among newly diagnosed rheumatoid arthritis patients doubled during the first 10 years after diagnosis.
The researchers collected data on 7,954 newly diagnosed rheumatoid arthritis patients and compared that information with 38,913 people from the general Swedish population.
Over 10 years of follow-up, the researchers found that patients diagnosed with rheumatoid arthritis had almost double the risk of a heart attack and dying from a heart attack. The increased risk grew over time, starting five years after diagnosis, the study found.
"This study shows that having rheumatoid arthritis confers an increased risk of having a myocardial infarction [heart attack], and that this risk increase is manifest already early in RA disease progress," Gunnarsson said in an ACR news release.
"The fact that there is no increased risk prior to rheumatoid arthritis diagnosis suggests that there is something in the rheumatoid arthritis disease itself, such as inflammatory processes that lead to this increased risk. Measures to bring down inflammation in rheumatoid arthritis might, thus, be beneficial also from a cardiovascular prevention point of view in this population," she said.
In the last report, a research team led by Dr. Kimberly Liang, an assistant professor at the University of Pittsburgh, found that diastolic dysfunction was more common in patients with rheumatoid arthritis, which could help explain the increased risk for heart problems in these people.
"Diastolic dysfunction occurred in 38.9 percent, compared to 28.8 percent in the non-rheumatoid arthritis group," Liang said. "We also found that patients in the rheumatoid arthritis group had higher average pulmonary arterial pressure, which is high blood pressure in the lungs and the right side of the heart. This is consistent with the impaired filling of the heart seen in diastolic dysfunction."
Wider use of echocardiography in patients with rheumatoid arthritis may reveal heart abnormalities before they are detected clinically, Liang said. An echocardiogram is a test that uses sound waves to create a moving picture of the heart, according to the U.S. National Institutes of Health.
Dr. John Hardin, chief science officer at the Arthritis Foundation, said these new studies highlight the toll that rheumatoid arthritis can take on the cardiovascular system.
"These studies are consistent with the idea that systemic inflammation promotes cardiovascular disease," Hardin said. "Rheumatoid arthritis creates a general state of inflammation within the body."
Hardin also noted that some arthritis drugs can increase the risk of heart problems in rheumatoid arthritis patients who already have damaged hearts. "For example, Enbrel (etanercept) can, in fact, in some people, potentiate heart failure, which can be a complication of myocardial infarction," he said.
To prevent a heart attack, patients with rheumatoid arthritis need to pay particular attention to cholesterol, blood pressure and maintaining a healthy lifestyle, Hardin said. "If you have rheumatoid arthritis, the things you do to protect yourself against cardiovascular disease become doubly important," he said.
Rheumatoid arthritis is a chronic disease that results in pain, stiffness, swelling, and limitation in the motion and function of multiple joints. The disease also can cause inflammation in other organs. An estimated 1.3 million Americans suffer from rheumatoid arthritis, according to the Arthritis Foundation.
To learn more about rheumatoid arthritis, visit the U.S. National Library of Medicine.