No one knows exactly what causes rheumatoid arthritis, but a variety of factors, including genetics and hormones are suspected. The hormone link may explain why women have proven to be at a much higher risk for the disease. Research indicates that between one and three percent of all women may develop rheumatoid arthritis in their lifetime, and women comprise approximately 70 percent of all people with the disease. The hormone connection also appears likely because of studies which demonstrate that the disease seems to go into remission during pregnancy, and the symptoms tend to increase in intensity after the baby is born. Research has also found that the disease often develops in the year after giving birth.
The Role of the Immune System
Unlike other forms of arthritis, which can result from wear and tear on the joints, rheumatoid arthritis is an autoimmune disease. That means it is an illness which occurs when the immune system malfunctions and produces antibodies or specialized cells which attack and damage the body's own tissues.
In a healthy individual, the immune system protects the body by fighting off foreign substances, called antigens, such as viruses and bacteria. When an autoimmune disease is present, the immune system seems to go into overdrive and starts reacting to the body's healthy cells as well. The result is often damaging inflammation in different organs, joints and body tissue.
In rheumatoid arthritis, inflammation primarily occurs in the membrane that lines the joint, called the synovium. This process is called synovitis and is responsible for the chronic pain, stiffness, swelling and limited motion and function that many people with rheumatoid arthritis experience. The inflammation can destroy the cartilage, bone and ligaments and can eventually cause the joints to become deformed. Most often it is the smaller joints that are affected, such as the ones in the hands, feet, wrists, elbows, knees and ankles.
