There are over 100 types of arthritis. While their symptoms can be similar, their underlying causes vary.
Published by NIH – Arthritis is an inflammation of the joints. There are over 100 types of arthritis. While their symptoms can be similar, their underlying causes vary. Osteoarthritis is the most common type of arthritis. It’s far more common than rheumatoid arthritis. Osteoarthritis is caused by wear and tear on your joints. In rheumatoid arthritis, your immune system—which normally helps protect your body from infection and disease—starts attacking your joint tissues.
Anyone can get rheumatoid arthritis. The disease most often begins in middle age or later. But it can occur at any age. Even children sometimes get a similar form of arthritis. Some types of arthritis affect one joint at a time, but rheumatoid arthritis can affect your whole body.
It’s important to get the correct diagnosis because each form of arthritis needs to be treated differently. To diagnose rheumatoid arthritis, doctors use medical history, physical exams, X-rays, and lab tests. There’s no single test for the disease. It’s not easy to diagnose.
“The joint swelling in rheumatoid arthritis is squishy, and very different from the hard bony enlargement of the finger joints that is sometime present in osteoarthritis,” explains Dr. Michael M. Ward, who oversees rheumatoid arthritis research at NIH. Your joints may appear red and feel warm. Pain and stiffness may be worse after you wake up or have been resting for a long time. Over time, your immune system damages the tough, flexible tissue (cartilage) that lines joints. This damage can be severe and deform your joints.
Scientists don’t know exactly what causes rheumatoid arthritis. It’s likely a combination of genetics and environmental triggers, such as tobacco smoke or viruses. Hormones may also play a role. More women are diagnosed with rheumatoid arthritis than men. The disease sometimes improves during pregnancy or flares up after pregnancy.
What scientists do know is that the damage is caused by the immune system gone awry. The body’s defense system mistakenly attacks the membrane that lines joints, such as in the wrists, fingers, and toes. Joints in the neck, knees, hips, ankles, and elsewhere can also be affected.
“The immune system is supposed to be something that does good things for you,” says Dr. M. Kristen Demoruelle, an NIH-funded arthritis expert at the University of Colorado Anschutz Medical Campus. “It’s supposed to help you fight infections. But in rheumatoid arthritis—for reasons that we don’t yet understand—the immune system gets confused and then starts to attack your joints instead.”
There’s no cure for rheumatoid arthritis. But there are effective treatments. Treatment can relieve pain, reduce joint stiffness and swelling, and prevent further joint damage.
Research advances have improved patient outcomes in the past 10 to 20 years. Doctors no longer wait to start treating a person with rheumatoid arthritis. Now, they know to begin treatment right away—before joint damage worsens. Early detection is very important to increase the chance that treatment is successful.
“If we can get you into low disease activity by 6 months and remission (no signs of the disease) by 1 year, we’ve got an incredibly good chance of the disease having a very minimal impact on your life,” says Dr. Vivian P. Bykerk, an NIH-funded arthritis researcher at the Hospital for Special Surgery in New York. There are many different classes of drugs available. Many of the drugs, like NSAIDs (nonsteroidal anti-inflammatory drugs) and steroids, work by reducing inflammation. Such drugs may be used in combination with others that have been shown to slow joint destruction.
NIH scientists helped develop a new class of drug for rheumatoid arthritis called Janus kinase (JAK) inhibitors. These drugs work by suppressing the body’s immune response. Several years ago, the first drug in this new class was approved by FDA for moderate to severe rheumatoid arthritis. Researchers continue to investigate new types of drugs and drug combinations.
“We really have to rely on our experience. We consider the combination of signs, symptoms, and blood tests to choose the right treatment,” Bykerk explains. Once treatment for rheumatoid arthritis is underway, patients need frequent checkups. Doctors may need to try and adjust different drugs or drug combinations to find the best fit for each person. Treatments are usually required for the long term to maintain control of the disease. For some people, symptoms go on for years, even a lifetime. Sometimes after months of mild disease, symptoms can flare up again.
Bykerk also works on an NIH-supported team of scientists who are searching for more effective treatment approaches. The team analyzes joint tissue and blood samples from people with rheumatoid arthritis to better understand the genes and proteins that trigger and drive the disease. The researchers aim to learn why some people respond differently to different treatments. They also hope to one day be able to tailor treatments to each person. Other studies are exploring how long people need to be treated once the disease is under control to prevent it from returning.
Rheumatoid arthritis can affect virtually every area of your life, from work to relationships. If you have rheumatoid arthritis, there are many things you can do to help maintain your lifestyle and keep a positive outlook. Exercise helps keep your muscles healthy and strong, preserve joint mobility, and maintain flexibility. Rest helps to reduce joint inflammation, pain, and fatigue. Ask your doctor how best to balance exercise and rest for your situation.
New research advances continue to help improve quality of life for people with rheumatoid arthritis. Talk with your doctor about how to treat your joint pain and stiffness so that you can lead a full, active, and independent life.
Written by NIH Office of Communications and Public Liaison
Editor: Harrison Wein, Ph.D.
Managing Editor: Tianna Hicklin, Ph.D.