10 Basic Facts About Rheumatoid Arthritis

But rheumatoid arthritis can occur at any age, from childhood to old age.

Patients who experience arthritis in only a few joints do better than those with more widespread (systemic) disease, which is very difficult to treat.

Women are more likely to develop RA than men.

Rheumatoid arthritis is most likely triggered by a combination of factors, including an abnormal autoimmune response, genetic susceptibility, and some environmental or biologic trigger, such as a viral infection or hormonal changes.

In autoimmune disorders, the body’s immune system mistakenly attacks and destroys healthy cells and tissue.

For reasons that are still not completely understood, both the T cells and the B cells become overactive in patients with RA.

Morning stiffness that lasts for at least an hour is associated with RA. Stiffness from osteoarthritis, in contrast, usually clears up within half an hour.

Swelling and pain in the joints must occur for at least 6 weeks before a diagnosis of rheumatoid arthritis is considered. The inflamed joints are usually swollen and often feel warm and "boggy" (spongy) when touched. The pain often occurs on both sides of the body (symmetrically) but may be more severe on one side of the body, depending on which hand the person uses more often.

In some patients with RA, inflammation of small blood vessels can cause nodules, or lumps, under the skin. They are about the size of a pea or slightly larger, and are often located near the elbow, although they can show up anywhere.