SF Logo

Arthritis Disease Research

What Is Arthritis?

The word arthritis means joint inflammation. According to the Centers for Disease Control (CDC), the term arthritis is used to describe more than 100 rheumatic diseases and conditions that affect joints, tissues that surround joints, and other connective tissue.

Symptom pattern, severity, and location can vary depending on the specific form of the disease. Typically, rheumatic conditions are characterized by pain and stiffness in and around one or more joints. The symptoms can develop gradually or suddenly. Certain rheumatic conditions can also involve the immune system and various internal organs of the body.

Arthritis is the most common cause of disability in the United States, limiting the activities of nearly 21 million adults, according to the CDC.

Among common types of arthritis in the United States are:

  • Osteoarthritis (OA). The most common type of arthritis, OA is a chronic condition in which a joint’s cartilage—the body’s “cushioning” tissue at the end of joints—breaks down, causing the bones to rub against each other and resulting in stiffness, pain, and loss of movement.
  • Rheumatoid arthritis (RA). An inflammatory disease, RA affects the lining of joints, but, as a systemic disease, can also impact other organs. The inflammation leads to erosions of the cartilage and bone and sometimes joint deformity. While its definitive cause is unknown, RA is believed to be the result of a faulty immune response.
  • Juvenile arthritis (JA). Juvenile arthritis is defined as any type of arthritis or arthritis-related condition developing in children less than 18 years of age. According to the Arthritis Foundation, more than 290,000 children under the age of 18 in the United States are affected by pediatric arthritis and rheumatologic conditions.

Other arthritis conditions include:

  • Infectious arthritis, caused by an infection that has spread from another part of the body to a joint.
  • Gout, a rheumatic disease caused by a buildup of uric acid in the body. Certain common medications, alcohol, and foods are known to be contributing factors. Acute symptoms are red, hot, and swollen joints with excruciating pain.
  • Systemic lupus erythematosus (SLE or lupus), an autoimmune disease that leads to widespread inflammation and tissue damage, with symptoms of fatigue, joint pain or swelling, skin rashes, and fevers.
  • Fibromyalgia, a syndrome predominately characterized by widespread muscular pain and fatigue.

Back to Top

What are the Risk Factors?

According to the CDC, a 2007-2009 National Health Interview Survey reported 50 million adults (22 percent) in the United States have self-reported doctor-diagnosed arthritis. Projections forecast this number to grow to 67 million (25 percent) by the year 2030.

Certain factors are associated with a greater risk of arthritis. The CDC describes risk factors that cannot be controlled:

  • Age. The risk of developing most types of arthritis increases with age.
  • Gender. Most types of arthritis are more common in women; 60 percent of all people with arthritis are women. Gout is more common in men.
  • Genetic. Specific genes are associated with a higher risk of certain types of arthritis, such as rheumatoid arthritis and lupus.

Modifiable risk factors include:

  • Overweight and obesity. Excess weight can contribute to both the onset and progression of knee osteoarthritis.
  • Joint injuries. Damage to a joint can contribute to the development of osteoarthritis in that joint.
  • Infection. Many microbial agents can infect joints and potentially cause the development of various forms of arthritis.
  • Occupation. Occupations involving repetitive knee bending and squatting are associated with osteoarthritis of the knee.

Treatment plans for arthritis include rest and relaxation, exercise, proper diet, and instruction on the proper use of joints. Most medications used to treat the various forms of rheumatic disease do not provide a cure, but limit disease symptoms, providing relief from pain and inflammation. In other cases, splints or braces are advised, and in severe cases, surgery may be necessary.

Back to Top

Recent Arthritis Research and News at The Scripps Research Institute

Back to Top

Links for General Arthritis Information

Back to Top

donate now