Rheumatoid arthritis is an autoimmune, systemic, inflammatory form of arthritis. It is a chronic, progressive disease. Joints are the main part of the body affected by rheumatoid arthritis, but systemic involvement is possible too, meaning that organs can be affected.

Joint damage develops differently in rheumatoid arthritis than osteoarthritis. With rheumatoid arthritis, immune cells go awry and attack the body's own healthy tissues. This happens when a three-phase inflammatory process takes place: Swelling of the joint lining (synovium) occurs; pannus (inflamed tissue spreads from the synovial membrane and invades the joint) causes the synovium to thicken; and inflamed cells release enzymes which can digest bone and cartilage, resulting in joint damage.

Symptoms of Rheumatoid Arthritis

As with osteoarthritis, rheumatoid arthritis can affect any joint. A major difference between the two most common forms of arthritis is that rheumatoid arthritis usually affects joints symmetrically. With rheumatoid arthritis, it is common for the same joint on both sides of the body to be affected (e.g., if your left knee is affected, your right knee will likely be affected too).

Rheumatoid arthritis causes joint pain, stiffness, swelling, redness, warmth, and limited range of motion. Damage can occur to tendons and ligaments, as well as bone and cartilage. Other signs and symptoms that point to rheumatoid arthritis include:

• Prolonged morning stiffness that lasts more than an hour

• Small joints of hands and feet commonly affected

• Malaise (a vague feeling of discomfort)

• Fatigue

• Low-grade fever

• Loss of appetite

• Rheumatoid nodules (a small collection or growth of tissue)

• Pain associated with prolonged sitting or staying in one position

• An association with Sjögren's syndrome (dry eyes and mouth)

Symptoms associated with rheumatoid arthritis are variable; the course of disease is not exactly alike for any two rheumatoid arthritis patients. Your individual course of disease may vary as well, as you experience periods of flares and remissions.

Diagnosis and Treatment of Rheumatoid Arthritis

Once again, there is no single test used to definitively diagnose rheumatoid arthritis. Other types of arthritis have similar symptoms, making rheumatoid arthritis difficult to diagnose. There are a number of diagnostic tools and factors that, used in combination, help formulate the diagnosis. A medical history and physical examination are used initially to search for symptoms.

Laboratory blood tests can reveal abnormalities consistent with having rheumatoid arthritis. Rheumatoid factor, erythrocyte sedimentation rate, C-reactive protein, and anti-CCP tests are routinely ordered to help diagnose rheumatoid arthritis. X-rays and MRIs (magnetic resonance imaging) are useful for showing evidence of joint damage. In the first few months after onset of the disease the evidence may not yet appear on x-ray images.

Early diagnosis is important so that treatment can begin. Decades ago, rheumatoid arthritis was treated conservatively. Conventional thinking was that patients should be treated with the least amount of medication that evoked a response. With the development of newer medications, some of which have the potential to slow disease progression and prevent severe joint erosions, researchers and the medical community agree that early, aggressive treatment is the way to go for patients who have no contraindications (i.e., reasons a patient should not take a particular medication).

There is no cure for rheumatoid arthritis, but treatment can help control symptoms and preserve joint function. Medications, along with other complementary treatments, are usually considered the best course of treatment for most rheumatoid arthritis patients. There are several medications used to treat rheumatoid arthritis, which you will read about in a later chapter. It is not uncommon for patients to try several treatments before deciding which ones yield optimum results. You may have to make changes to your treatment plan several times over the course of months and years.

Risk Factors and Prevalence of Rheumatoid Arthritis

Numerous studies have looked at what causes the abnormal immune response associated with rheumatoid arthritis. Genetic predisposition combined with a triggering event is a popular theory.

Rheumatoid arthritis can affect anyone of any age, including children. Typically, the age of onset for rheumatoid arthritis is between thirty and sixty years of age. Approximately 2.1 million people in the United States are affected by rheumatoid arthritis (about 1 percent — 2 percent worldwide). About 70 to 75 percent of rheumatoid arthritis patients are women. Of lifestyle factors, smoking has been shown to increase the risk of developing rheumatoid arthritis.