What Are The 4 Stages Of Rheumatoid Arthritis? Rheumatoid arthritis (RA) is a chronic autoimmune disease that primarily affects the joints, causing inflammation, pain, and stiffness. Unlike osteoarthritis, which is caused by wear and tear on the joints, RA occurs when the immune system mistakenly attacks the synovium—the lining of the joints—leading to inflammation and damage. Over time, this inflammation…
