SUNDAY, Nov. 7 (HealthDay News) -- Inflammation associated with rheumatoid arthritis may damage more than the joints, new research suggests.
The autoimmune disorder may also increase the risk of atherosclerosis, a buildup of plaque in the blood vessels, potentially increasing the risk of stroke and heart disease, researchers say.
The good news from the study is that certain drugs already used in the treatment of rheumatoid arthritis appear to lessen the risk of plaque buildup.
"Cardiovascular risk is higher in people with rheumatoid arthritis, but this is not a done deal," said study lead author Dr. Jon T. Giles, an assistant professor of medicine in the division of rheumatology at Johns Hopkins University in Baltimore.
"There is some suggestion that inflammatory risk factors [such as those from rheumatoid arthritis] really only make a difference in people who have other risk factors for cardiovascular disease [such as obesity or a sedentary lifestyle], so it's important to control your traditional cardiovascular risk factors," Giles said.
The study results were scheduled to be presented Sunday at the annual scientific meeting of the American College of Rheumatology in Atlanta.
Rheumatoid arthritis is a chronic disease caused by inflammation in the lining of the joints. It can lead to significant, chronic joint pain, according to the Arthritis Foundation. The exact cause of the disease is unknown, but the immune system is believed to play a key role in its development. Instead of concentrating its fighting capabilities on foreign invaders, such as bacteria, the immune system in people with rheumatoid arthritis appears to turn against the healthy tissue that lines the area between joints, damaging or destroying it.
In the current study, researchers conducted two ultrasound exams of the carotid arteries in 158 people with rheumatoid arthritis. The first test was done at the start of the study, and the second was done an average of about three years later.
About two-thirds of the study participants were female, and their average age was 59 years at the beginning of the study.
The researchers measured the thickness of the common carotid artery and the internal carotid artery. The carotid arteries provide crucial blood flow to the brain.
In between scans, 82 percent of people had some thickening in their common carotid artery, while 70 percent had thickening in the internal carotid artery, according to the study.
People who were treated with TNF-inhibiting medications, such as infliximab (Remicade) or adalimumab (Humira), had a 37 percent lower rate of thickening in their common carotid artery compared to people not on the medication.
However, not all medications were helpful. Those taking corticosteroids, such as prednisone, had an increased risk of carotid thickening, unless they were also taking a cholesterol-lowering medication known as a statin. Statin use seemed to counter the negative effect of the steroid, according to the study.
High levels of inflammation in the body were associated with increased plaque deposits, Giles noted.
"These are slowly progressive changes. It's not as if these plaques are limiting blood flow; they're more subtle changes, but by attenuating risk factors, and potentially intervening early on, we may be able to make a difference," Giles said.
Dr. Nadera Sweiss, a rheumatologist with the University of Chicago Medical Center, said the study supports the concept of inflammation and its relationship to atherosclerosis.
"But it's not clear how we can change the outcome yet," she said.
"I think this study will push all of us to think more about modifiable risk factors when we see patients with rheumatoid arthritis," said Sweiss. "If someone is overweight, I may pay more attention and refer to a dietitian earlier on, or look at the lipids and think about using statins and counseling on how to lower LDL ["bad" cholesterol] and raise HDL ["good"] cholesterol," she added.
"It's crucial that we look at rheumatoid arthritis much the same way we look at diabetes and other diseases that can affect the heart adversely," Sweiss said.
Learn more about rheumatoid arthritis from the Arthritis Foundation.
SOURCES: Jon T. Giles, M.D., M.P.H., assistant professor of medicine, division of rheumatology, Johns Hopkins University, Baltimore; Nadera Sweiss, M.D., rheumatologist, University of Chicago Medical Center; Nov. 7, 2010 presentation, American College of Rheumatology annual meeting, Atlanta
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