Rheumatoid arthritis (RA) is an autoimmune disease. It causes pain, swelling, stiffness, and loss of function in the joints.

Rheumatoid Arthritis
rheumatoid arthritis
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RA is caused by a combination of genetic and environmental factors that trigger an abnormal immune response. Possible causes include:

  • Genes—People with rheumatoid arthritis may have a specific genetic defect that increases their risk for developing this condition.
  • Defects in the immune system may cause the immune cells to fail to recognize the body’s own tissues.
  • Infection with specific viruses or bacteria that kick off an abnormal immune response.
  • Chemical or hormonal imbalances in the body.