Causes of Rheumatoid Arthritis (RA)

Rheumatoid arthritis (RA) is a disease that results in chronic joint inflammation. Although scientists worldwide are in engaged in active research about the origins of RA, a definitive link to any one cause has yet to be determined. Scientific speculations about the causes of Rheumatoid Arthritis range from infection to hormone imbalance to genetic disorders. What follows is a list of possible causes and risk-factors associated with RA.

Possible Causes of Rheumatoid Arthritis

Infections: Bacteria have long been suspected as a possible cause of rheumatoid arthritis. The thought is that the immune system may overreact to bacteria, viruses or fungi, and continue to attack the infected area even after the infection has been eradicated.

• Chemical Exposure: Certain chemicals have also been linked to the onset of rheumatoid arthritis, although research has yet to firmly establish this theory.
• Immune System Malfunction: The immune system may also be mistaking natural body chemicals or tissues as foreign invaders, and is attempting to destroy them.
• Genetics: Heredity and genetics probably play some role in determining who develops rheumatoid arthritis and who doesn't. The genetic marker HLA-DR4 shows up in many people with RA, and is considered a predictor of genetic predisposition to the disease. HLA-DR4 does not, however, show up in all cases of rheumatoid arthritis.
• Hormones: Due to the much higher rate of rheumatoid arthritis in women, hormone levels have been suggested as a possible cause. Exactly how hormones influence the disease, if at all, has yet to be fully explained.

Recent Research: Are Carbohydrates to Blame?

Current research suggests that the body's immune system may be reacting to certain types of carbohydrates normally found in the body. These carbohydrates, called glycosaminoglycans (GAG) are found naturally in cartilage and connective tissues. Immune cells may be accidentally targeting these GAG carbohydrates and attempting to destroy them (auto-immunity). This buildup of immune cells could be the cause of RA inflammation.

Risk Factors for Rheumatoid Arthritis

Although the incidence of rheumatoid arthritis increases with age, many people experience their first symptoms in their twenties and thirties. The disease can strike at even earlier ages, so simply getting older may not be a significant risk factor. Because untreated rheumatoid arthritis becomes worse over time, it may be fair to say that the symptoms exhibited by older people may be more severe, rather than attributing immunity to younger people. Other risk factors include:

• Gender: Being female increases your chance of developing rheumatoid arthritis enormously: three times more women than men developing the disease.
• History: A family history of arthritis also increases the risks.
• Smoking: Research suggests that smokers have higher rates of rheumatoid arthritis than non-smokers.

Juvenile Rheumatoid Arthritis

Juvenile rheumatoid arthritis (JRA) causes joint inflammation, stiffness, and swelling of the joints in children under the age of 16. It differs from adult rheumatoid arthritis in that 80 percent of children affected "grow out" of the disease by adulthood.

The symptoms of juvenile rheumatoid arthritis are not constant: stiffness and pain experienced in the morning often disappear by lunchtime. Children are most likely to develop the disease between the ages of two and five or between nine and twelve.

Juvenile rheumatoid arthritis can be divided into three categories.

• Pauciarticular: Painful swelling and inflammation in one to four joints; the most common type, accounting for approximately fifty percent of all cases.
• Polyarticular: Affects large and small joints; 35 percent suffer joint inflammation in five or more joints.
• Systemic: Joint inflammation combined with high fever and skin rash; affects fifteen percent of children with JRA.

Resources

Arthritis Foundation. (updated 2004). Rheumatoid arthritis (RA).

Ebrahimi, S. (1999). Rheumatoid arthritis.

Manning, A. (2002). Carbohydrates may be the culprit behind painful rheumatoid arthritis. USA Today.

National Jewish Medical and Research Center. (updated 2005). Juvenile rheumatoid arthritis bytes.

National Library of Medicine. (updated 2003). Juvenile rheumatoid arthritis. MedlinePlus Medical Encyclopedia.

National Library of Medicine. (updated 2004). Rheumatoid arthritis. MedlinePlus Medical Encyclopedia.

Shiel, W.C. (reviewed 2002). Rheumatoid arthritis. MedicineNet, Inc.

Wright, K. (2001). Rheumatoid Arthritis. Gale Encyclopedia of Alternative Medicine.