As with other autoimmune diseases, RA is caused by the immune system inappropriately targeting ‘self’ tissues or proteins. The mechanism by which this occurs is an active area of research but is not well understood. In the case of RA, the immune system targets the synovial lining of joints, causing inflammation and progressive damage to the joint and eventual loss of joint function. Both genetics and environmental factors are known to play a role in the disease, but the specific mechanisms driving the autoimmunity are not clear.
What causes rheumatoid arthritis?
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•Last Updated: May 16, 2025
Rheumatoid arthritis is caused by the immune system mistakenly attacking the body's own tissues, particularly the synovial lining of joints, which leads to inflammation and joint damage. Although both genetic and environmental factors contribute to the disease, the exact mechanisms behind this autoimmune response remain unclear.