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What are the most common types of arthritis?
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The most common types of arthritis are osteoarthritis, rheumatoid arthritis, psoriatic arthritis and gout. Osteoarthritis is a degenerative joint disease that affects many people as they age. It causes pain, swelling and stiffness in the joints. Rheumatoid arthritis is an autoimmune disorder that causes inflammation and damage to the joints and other body parts. Psoriatic arthritis is an inflammatory form of arthritis that occurs when the immune system attacks the joints. Gout is caused by too much uric acid in the bloodstream. This can lead to painful swelling, redness, and tenderness in the joints.