WebMD 5: Rheumatoid Arthritis
Our expert explains rheumatoid arthritis and what's ahead for treatment.
Rheumatoid arthritis (RA) is perhaps the most common inflammatory arthritis in the world, says Gary S. Firestein, MD, professor of medicine, dean and associate vice chancellor of translational medicine at the University of California, San Diego School of Medicine. In the United States, an estimated 1.3 million people have the disease, and it affects two to three times as many women as men. And RA may be on the rise in women, according to a 2010 Mayo Clinic study. After decades of decline, the incidence of RA rose modestly among women during 1995 to 2007, researchers found.
Although it's too soon to tell if RA is still increasing or if environmental factors such as smoking (a known risk factor) are to blame, what is clear is that therapy has improved significantly in the past 10 to 20 years, Firestein says. "The majority of our patients, if not in remission, have markedly improved symptoms." Firestein answers some top questions about RA.
1. What causes RA and what are the symptoms?
Nobody really knows, except we do know it involves both genetics and the environment. The risk of developing RA is about 1% in the general population. But if you have a first-degree relative -- like a sister or a mother -- with RA, then your chance of getting the disease increases from 1% to the 2% to 5% range. If you have an identical twin with RA, the risk goes up from 12% to 15%, so that clearly shows genes can play a role. There's probably not a single environmental factor responsible, such as a virus.
The symptoms are swelling and pain and stiffness in the joints, especially stiffness in the morning. In general, it is symmetrical, which means it involves both sides of the body. Typically a person with RA will have swelling and pain in the wrists, knuckles, ankles, and toes.
As the disease progresses, larger joints will be involved: elbows, shoulders, knees, and hips. The pain is usually not severe, but more chronic and dull. RA can cause flares but often includes periods where disease activity is much lower. Fatigue is quite common with active RA, where affected joints have an increase in inflammation with swelling and redness.