Rheumatoid arthritis (RA) is a long-term disease. It leads to inflammation of the joints and surrounding tissues. It can also affect other organs.
RA; Arthritis - rheumatoid
The cause of RA is unknown. It is an autoimmune disease. This means the body's immune system mistakenly attacks healthy tissue.
RA can occur at any age, but is more common in middle age. Women get RA more often than men.
Infection, genes, and hormone changes may be linked to the disease. Smoking may also be linked to RA.
It is much less common than osteoarthritis, which is a condition that occurs in many people due to wear and tear on the joints as they age.