The exact cause of rheumatoid arthritis is not known. Rheumatoid
arthritis is an autoimmune disorder, which means the body's immune
system attacks its own healthy cells and tissues. The response of the
body causes inflammation in and around the joints, which then may lead
to a destruction of the skeletal system.
Rheumatoid arthritis also may have devastating effects to other
organs, such as the heart and lungs. Researchers believe certain
factors, including heredity, may contribute to the onset of the disease.