Arthritis refers to inflammation of joints. RA is one of the most common forms of arthritis. Up to 1% of the general population may be affected by RA and it can happen at any age. RA is more common in women.
RA is an autoimmune disease. There are some genetic factors as well as other factors such as smoking that increase the risk of RA. The immune system normally protects us from infection by attacking germs such as bacteria and viruses. However, in people who develop autoimmune diseases, the immune system is confused and overactive, and attacks our own body. This causes joint inflammation that will eventually damage the joint, cartilage and surrounding bones. The most commonly affected joints in RA are the small joints of the hands, wrists, ankles and feet. However, any joints can be affected.