Rheumatoid arthritis is a condition in which the immune system attacks joints in the body, causing joint damage, pain and deformity, according to "Current Medical Diagnosis and Treatment" by Stephen J. McPhee and Maxine Papadakis. Symptoms include joint pain, tenderness and swelling. In addition, it can cause bumps called rheumatoid nodules to form under the skin and in the organs, fatigue, stiffness, weight loss and fevers. The mechanism of the disease is unknown. However, several risk factors have been defined.
Genetics
The exact role of genes in the development of rheumatoid arthritis is unknown. Genes involving the regulation of the immune system may be involved. Identical twins are more likely to both get rheumatoid arthritis than non-identical twins. However, if one of a pair of identical twins develops rheumatoid arthritis, it is not certain that the other twin will develop it, so other environmental factors are also responsible.
Gender
Women are significantly more likely to develop rheumatoid arthritis than men, according to "Harrison's Principles of Internal Medicine" by Anthony S Fauci MD. In addition, never having been pregnant is associated with increased risk of developing the disease. Breastfeeding decreases the risk, and pregnancy may have a therapeutic effect.
Tobacco
Tobacco use also may increase the risk of developing rheumatoid arthritis. The duration of smoking appears to be more of a significant factor than the number of cigarettes. Smoking also makes the disease worse, and cessation improves outcomes.
Infection
Infections with viruses and bacteria have also been linked to the disease. The mechanism by how this occurs is unknown. It may be that in susceptible persons, particular infectious agents trigger an abnormal immune response. The immune system then attacks joints and causes rheumatoid arthritis.
Antibodies
Antibodies are proteins made by the immune system that inactivate invading pathogens and bind to foreign proteins. Abnormal antibodies can attack the body's own proteins. These are called auto-antibodies. A certain auto-antibody called RF is higher in those with the disease, but its presence alone does not mean a person will develop rheumatoid arthritis, according to "Kelley's Textbook of Rheumatology" by Gary S. Firestein MD.
References
- "Current Medical Diagnosis and Treatment"; Stephen J. McPhee and Maxine Papadakis; 49th Ed 2010
- "Harrison's Principles of Internal Medicine" Anthony S Fauci et al; 17th Ed 2008
- "Kelley's Textbook of Rheumatology"; Gary S. Firestein MD et al; 8th Ed 2008
