Rheumatoid Arthritis Health Article

Definition

Rheumatoid arthritis is an inflammatory disease that causes pain, swelling, stiffness, and loss of function in the joints.

The course of RA varies from person to person. For some persons, it lasts only a few months or 1 to 2 years and resolves without causing any noticeable damage. Other persons have mild or moderate forms of the disease, with periods of worsening symptoms, called flares, and periods in which they improve, called remissions. Still others have a severe form of the disease that is active most of the time, lasts for many years or a lifetime, and leads to serious joint damage and disability.

Although RA can have serious effects on a person's life and well-being, current treatment strategies—including analgesics and medications that slow joint damage, a balance between rest and exercise, and patient education and support programs—allow most affected persons to lead active and productive lives.

Like many other rheumatic diseases, RA is an autoimmune disease. White blood cells travel to the synovium and cause synovitis, a condition characterized by warmth, redness, swelling, and pain. During the inflammation process, the normally thin synovium thickens and creates swelling of the joint. As RA 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 function normally.

Researchers studying RA now believe that bone damage begins during the first 1 to 2 years that a person has the disease, making early diagnosis and treatment very important.

Scope

Scientists estimate that about 2.1 million persons, or between 0.5% and 1% of the US adult population, have RA. Interestingly, some recent studies have suggested that the incidence of RA actually may be decreasing.

Rheumatoid arthritis occurs in all races and ethnic groups. Although the disease often begins in middle age and occurs with increased frequency in older persons, RA also may develop in children and young adults. Like some other forms of arthritis, RA occurs much more frequently in women than in men. About 2 to 3 times as many women as men have the disease.

By all measures, the financial and social impact of all types of arthritis, including RA, is substantial, both for the nation and its citizens. From an economic standpoint, the medical and surgical treatment for RA and the wages lost because of disability caused by the disease add up to billions of dollars annually.

Etiology

The causes of autoimmunity in RA are unknown, but research over the last few years has begun to piece together the factors involved. These factors include the following:

Genetic Factors

Scientists have discovered that certain genes known to play a role in the immune system are associated with a tendency for RA to develop. Some persons with the disease do not have these particular genes; others have these genes, but the disease never develops. These somewhat contradictory data suggest that a person's genetic makeup plays an important role in determining whether RA will develop, but it is not the only factor. What is clear, however, is that more than a single gene is involved in determining whether RA develops and how severe the disease will become.

Environmental Factors

Many scientists think that something must occur to trigger the disease process in persons whose genetic makeup makes them susceptible to RA. A viral or bacterial infection appears likely, but the exact agent is not yet known.

Other Factors

Some scientists also believe that a variety of hormonal factors may be involved in the development of RA. Rheumatoid arthritis is more likely to occur in women than in men. Symptoms may be reduced in pregnancy, though the disease may flare after a pregnancy. In addition, breastfeeding may aggravate the disease. Contraceptive use also may alter a person's risk of RA. Scientists think that levels of the immune system molecules interleukin 12 and tumor necrosis factornullα may change along with the changing hormone levels seen in pregnant women. This change may contribute to the swelling and tissue destruction seen in RA. These hormones, or possibly deficiencies or changes in certain hormones, may promote the development of RA in a genetically susceptible person who has been exposed to a triggering agent from the environment.

Signs And Symptoms

The following are signs and symptoms of RA:

• tender, warm, swollen joints;
• symmetrical pattern of affected joints;
• joint inflammation often affecting the wrist and metacarpal joints;
• joint inflammation sometimes affecting other joints, including the neck, shoulders, elbows, hips, knees, ankles, and feet;
• fatigue;
• anemia;
• dryness of the eyes and mouth;
• occasional fevers, and a general sense of not feeling well;
• pain and stiffness lasting for >30 minutes in the morning or after a long rest; and rarely,
• vasculitis, pleuritis, or pericarditis.