Rheumatoid Arthritis (RA) and Autoimmune DiseasesWhat do rheumatoid arthritis (RA), type 1 diabetes, Graves' disease, and multiple sclerosis have in common? One affects joints, another blood sugar.Rheumatoid Arthritis (RA) and Autoimmune DiseasesWebMD explains what makes RA an autoimmune disease. Learn what autoimmune diseases are and how changes involving your immune system lead to RA.Rheumatoid Arthritis - Fred Hutchinson Cancer Research CenterRheumatoid arthritis is one of the most common chronic autoimmune diseases, in which the body's immune system attacks its own tissues. Like other autoimmune diseases ...