11/24/2014 03:48 PM EST
Source: National Institute of Arthritis and Musculoskeletal and Skin Diseases -
Related MedlinePlus Page: Psoriatic Arthritis
Related MedlinePlus Page: Psoriatic Arthritis
Psoriatic Arthritis Overview
What Is Psoriatic Arthritis?
Psoriatic arthritis is a form of arthritis (joint inflammation) that can occur in people who have the skin disease psoriasis. Psoriasis is a common condition characterized by scaly red and white skin patches. Psoriatic arthritis can affect any joint in the body, including the spine.
Anyone can be affected by psoriatic arthritis, but it is more common in Caucasians than African Americans or Asian Americans. It most commonly appears between the ages of 30 and 50, but it can also begin in childhood. According to the Centers for Disease Control and Prevention (CDC), 10 to 20 percent of people with psoriasis eventually develop psoriatic arthritis. Typically, skin disease precedes the arthritis, sometimes by several years. However, in some cases, arthritic symptoms appear first.
The cause of psoriatic arthritis is not known; however, doctors believe a combination of genetic and environmental factors is involved. Research shows that people with psoriatic arthritis often have a family member with psoriasis or arthritis. In people who are susceptible, an infection may activate the immune system, triggering the development of psoriatic arthritis.
Psoriatic arthritis affects both the skin and the musculoskeletal system. The joints most commonly affected are the distal joints (those closest to the nail) of the fingers or toes, as well as the wrists, knees, ankles, and lower back.
The diagnosis of psoriatic arthritis is made based on the findings of a medical and family history and physical exam as well as x rays or magnetic resonance imaging (MRI) of the affected joints. Although there is no lab test to diagnose psoriatic arthritis, your doctor may order tests on blood or joint fluid to rule out other forms of arthritis with similar symptoms. If you have psoriasis and start to develop joint pain, it’s important to see your doctor. Early diagnosis and treatment of psoriatic arthritis can help prevent irreparable joint damage.
Treatment for psoriatic arthritis will depend largely on its severity. If the disease is mild and affects only a couple of joints, treatment with nonsteroidal antiinflammatory drugs (NSAIDs)1 may be sufficient for treating pain and inflammation. For acutely inflamed joints, corticosteroid injections may be helpful. For more persistent disease affecting multiple joints, stronger disease-modifying antirheumatic drugs (DMARDs) and/or antitumor necrosis factor (TNF) agents may be needed to control the disease.2
1 Warning: NSAIDs can cause stomach irritation or, less often, they can affect kidney function. The longer a person uses NSAIDs, the more likely he or she is to have side effects, ranging from mild to serious. Many other drugs cannot be taken when a patient is being treated with NSAIDs because NSAIDs alter the way the body uses or eliminates these other drugs. Check with your health care provider or pharmacist before you take NSAIDs. Also, NSAIDs sometimes are associated with serious gastrointestinal problems, including ulcers, bleeding, and perforation of the stomach or intestine. People age 65 and older, as well as those with any history of ulcers or gastrointestinal bleeding, should use NSAIDs with caution.
2 All medicines can have side effects. Some medicines and side effects are mentioned in this publication. Some side effects may be more severe than others. You should review the package insert that comes with your medicine and ask your health care provider or pharmacist if you have any questions about the possible side effects.
Researchers throughout the United States and the world are conducting research that will eventually improve the understanding and outcomes of psoriatic arthritis.
Some promising areas of research include:
Genetics. Scientists supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) are working to uncover genes associated with psoriasis, as well as modifier genes that can indicate which people with psoriasis are also at risk for psoriatic arthritis. Identification of genes that increase the risk of psoriatic arthritis will help scientists unlock the secrets of this troubling disease, and identify targets for more specific and effective therapy.
Biologic therapies. Biologic therapies that block the inflammatory cytokine TNF have proven to be among the most effective therapies for psoriatic arthritis. A number of other biologic agents are currently in clinical trials for psoriatic arthritis, and researchers continue to look for targets of biologic therapy for the disease.
Role of vitamin D. A recent study showed that vitamin D insufficiency is common in people with psoriatic arthritis. A new study supported by the NIAMS is designed to investigate the effects of vitamin D supplementation, along with marine omega-3 fatty acid and docosahexaenoic acid (DHA), on incidence, inflammation, and chronic pain in autoimmune diseases including psoriatic arthritis.
Risk factors. To better understand what causes psoriatic arthritis, with the eventual goal of stopping its development, scientists are looking into factors that predict risk of arthritis among people with psoriasis. One recent study found that people with psoriasis who reported being obese at age 18 were more likely to develop arthritis and develop it at an earlier age than people with a normal body mass index (BMI). Other research has shown that more severe skin disease is predictive of an increased risk of joint disease.
Diagnostics. The similarity between psoriatic arthritis and other inflammatory forms of arthritis can delay an accurate diagnosis, particularly when the arthritis precedes the skin disease. One group of researchers looking for better ways to diagnose the disease has found that a technique called contrast-enhanced MRI may help doctors differentiate between rheumatoid arthritis and psoriatic arthritis in the hand and wrist, which would enable them to target therapies to each condition.
American College of Rheumatology
National Psoriasis Foundation
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The mission of the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), a part of the U.S. Department of Health and Human Services’ National Institutes of Health (NIH), is to support research into the causes, treatment, and prevention of arthritis and musculoskeletal and skin diseases; the training of basic and clinical scientists to carry out this research; and the dissemination of information on research progress in these diseases. The NIAMS information clearinghouse is a public service sponsored by the NIAMS that provides health information and information sources. Additional information can be found on the NIAMS website atwww.niams.nih.gov.
The National Institutes of Health (NIH)—The Nation’s Medical Research Agency—includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. It is the primary Federal agency for conducting and supporting basic, clinical, and translational medical research, and it investigates the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit www.nih.gov.
For Your Information
This publication contains information about medications used to treat the health condition discussed here. When this publication was developed, we included the most up-to-date (accurate) information available. Occasionally, new information on medication is released.
For updates and for any questions about any medications you are taking, please contact
U.S. Food and Drug AdministrationToll Free: 888–INFO–FDA (888–463–6332)
Website: http://www.fda.govFor additional information on specific medications, visit Drugs@FDA atwww.accessdata.fda.gov/scripts/cder/drugsatfda. Drugs@FDA is a searchable catalog of FDA-approved drug products.
For updates and questions about statistics, please contact
Centers for Disease Control and Prevention, National Center for Health StatisticsWebsite: http://www.cdc.gov/nchs
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Additional copies of this publication are available from:
National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
National Institutes of Health
NIH Publication No. 14–AR-8001