Rheumatoid arthritis is an autoimmune disease in which the body's defenses attack its own tissues. It is more common in women, tends to strike between the ages of 36 and 50, and results in a chronic destruction and deformity of the joints.

Approximately 3 out of 10 patients with rheumatoid arthritis will develop the most severe form of the disease over a 20-year period.

In the study researchers followed over 100 patients with rheumatoid factor-positive arthritis. Rheumatoid factor is a type of antibody found in the blood of about 70% of rheumatoid arthritis patients. Those with more severe disease generally have such antibodies.

At the beginning of the study, treatment was restricted to four drugs, while after 1982 doctors had additional drugs to treat the patients, including sulfasalazine and methotrexate. However, most patients continued to be treated with no more than one drug at a time.

The investigators observed a disease progression of about 2% to 3% per year in terms of the joint destruction. By the end of the study, two patients had the maximum score in terms of joint destruction, while 23% had high scores.

People with the most severe disease usually had at least three large joints, such as the hip, knee or shoulder, surgically replaced.

The Journal of Rheumatology 2002;29:688-692