What is rheumatoid arthritis?
Arthritis is a general term that describes inflammation in joints.
Inflammation is characterized by redness, warmth, swelling and pain.
Rheumatoid arthritis is a type of chronic (ongoing) arthritis that occurs in
joints on both sides of the body (such as both hands, wrists or knees). This
symmetry helps distinguish rheumatoid arthritis from other types of arthritis.
In addition to affecting the joints, rheumatoid arthritis may occasionally
affect the skin, eyes, lungs, heart, blood, nerves or kidneys.
What are the symptoms of rheumatoid arthritis?
- Joint pain
- Joint swelling
- Stiffness – especially in the morning or after sitting for long periods
- Fatigue – best defined as tiredness and excessive sleepiness
How does rheumatoid arthritis affect people?
Rheumatoid arthritis affects everyone differently. In most people, joint
symptoms may develop gradually over several years. In other people, rheumatoid
arthritis may progress rapidly. Other people may have rheumatoid arthritis for a
limited period of time and then enter a remission (a time with no symptoms).
Who is affected by rheumatoid arthritis?
Rheumatoid arthritis affects more than 1% of the United States population. It is
three times more common in women than men. It usually occurs in people between
the ages of 20 to 50; however, young children and the elderly can also develop
rheumatoid arthritis.
What causes rheumatoid arthritis?
The exact cause of rheumatoid arthritis is unknown. However, it is believed to
be caused by a combination of genetic, environmental and hormonal factors.
Normally, the immune system protects the body from infection. In rheumatoid
arthritis, something triggers the immune system to attack the joints and
sometimes other organs. Some theories suggest that a virus or bacteria may alter
the immune system, causing it to attack the joints. Some people have a genetic
or inherited factor that makes them more likely to develop rheumatoid arthritis.
What are the results of joint inflammation?
Once the immune system is triggered, cells migrate from the blood into the
joints and produce substances that cause inflammation.
The increased number of cells and inflammatory substances within the joint
cause:
- Irritation
- Wearing down of cartilage (cushions at the end of bones)
- Swelling of the joint lining (synovium)
- Production of fluid in the joint lining
As the cartilage wears down, the space between the bones narrows. If the
condition worsens, the bones could rub against each other.
As the joint lining grows, it may invade or erode into the bone, resulting in
irreversible damage to the bone. All of these factors cause the joint to become
very painful, swollen and warm to touch.