Rheumatoid arthritis (RA) is the most common inflammatory form of arthritis. It is characterized by inflammation of the synovial (joint) lining of multiple joints, usually presenting in a symmetric manner (meaning one side is like the other).

Early on, small joints such as the hands, wrists, ankles, and feet are involved. As the disease progresses, larger joints also are affected. Virtually, any joint can be involved.

Rheumatoid arthritis is an acquired autoimmune disease with a genetic predisposition. About 70% of patients have the genetic markers, HLA-DR4 or HLA-DR1.

Rheumatoid factors, which are antibodies to IgG, occur in 60-80% of adult RA patients. The level of rheumatoid factor in the blood seems to correlate with prognosis.

The three abnormal factors that seem to be associated with the development of RA are an environmental trigger (the exact trigger is still unknown), genetic predisposition, and a hyper normal immune response.

RA affects about 1-2% of the population (2 million people) with a female to male ratio of about 3:1. Mortality in patients with RA is increased compared with the general population. Life expectancy is reduced about 7 years in men and 4 years in women.

The economic impact is staggering! Direct costs are $14 billion per year in the United States. After 5 years of disease, 27% of people are disabled. After 10 years between 40 to 60% of people are disabled.