What Happens to the Joints?
Rheumatoid arthritis is primarily a disease of the joints.
Like many other rheumatic diseases, rheumatoid arthritis is an autoimmune disease (auto means self), so-called because a person’s immune system, which normally helps protect the body from infection and disease, attacks joint tissues for unknown reasons. White blood cells, the agents of the immune system, travel to the synovium and cause inflammation (synovitis), characterized by warmth, redness, swelling, and pain—typical symptoms of rheumatoid arthritis. During the inflammation process, the normally thin synovium becomes thick and makes the joint swollen puffy, and sometimes warm to the touch.
As rheumatoid arthritis progresses, the inflamed synovium invades and destroys the cartilage and bone within the joint. The surrounding muscles, ligaments, and tendons that support and stabilize the joint become weak and unable to work normally. These effects lead to the pain and joint damage often seen in rheumatoid arthritis. Researchers studying rheumatoid arthritis now believe that it begins to damage bones during the first year or two that a person has the disease, one reason why early diagnosis and treatment are so important.
Some people with rheumatoid arthritis also have symptoms in places other than their joints. Many people with rheumatoid arthritis develop anemia, or a decrease in the production of red blood cells. Other effects that occur less often include neck pain and dry eyes and mouth. Very rarely, people may have inflammation of the blood vessels (vasculitis), the lining of the lungs (pleurisy), or the sac enclosing the heart (pericarditis).
What Causes Rheumatoid Arthritis?
Scientists still do not know exactly what causes the immune system to turn against the body’s own tissues in rheumatoid arthritis, but research over the last few years has begun to piece together the factors involved.
- Genetic (inherited) factors: Scientists have discovered that certain genes known to play a role in the immune system are associated with a tendency to develop rheumatoid arthritis. For the genes that have been linked to rheumatoid arthritis, the frequency of the risky gene is only modestly higher in those with rheumatoid arthritis compared with healthy controls. In other words, individual genes by themselves confer only a small relative risk of disease. Some people who have these particular genes never develop the disease. These observations suggest that although a person’s genetic makeup plays an important role in determining if he or she will develop rheumatoid arthritis, it is not the only factor. What is clear, however, is that more than one gene is involved in determining whether a person develops rheumatoid arthritis and how severe the disease will become.
- Environmental factors: Many scientists think that something must occur to trigger the disease process in people whose genetic makeup makes them susceptible to rheumatoid arthritis. A variety of factors have been suggested, but a specific agent has not been identified.
- Other factors: Some scientists also think that a variety of hormonal factors may be involved. Women are more likely to develop rheumatoid arthritis than men. The disease may improve during pregnancy and flare after pregnancy. Breastfeeding may also aggravate the disease. Contraceptive use may increase a person’s likelihood of developing rheumatoid arthritis. This suggests hormones, or possibly deficiencies or changes in certain hormones, may promote the development of rheumatoid arthritis in a genetically susceptible person who has been exposed to a triggering agent from the environment.
Even though all the answers are not known, one thing is certain: rheumatoid arthritis develops as a result of an interaction of many factors. Researchers are trying to understand these factors and how they work together.
Source: Vivacare
Last updated : 9/22/2015