Who Is at Risk for Psoriatic Arthritis?
Affecting men and women equally, approximately 10% to 30% of people with psoriasis develop psoriatic arthritis. Psoriatic arthritis may develop at any age, but usually affects people between the ages of 30 and 50. While the cause is not known, genetic factors, along with the immune system, infection, and physical trauma likely play a role in determining who will develop the disorder.
As many as 40% of people with psoriatic arthritis have a family history of skin or joint disease. Having a parent with psoriasis triples the chance of getting psoriasis yourself and thus increases the chance of developing psoriatic arthritis.
How Is Psoriatic Arthritis Diagnosed?
The diagnosis of psoriatic arthritis is based on the following:
- Appearance of symptoms (as described above)
- Complete evaluation of your medical history
- Physical exam
- Blood tests
- X-rays of the joints
Diagnosis may be easier for your doctor to confirm if psoriasis is also present with arthritis symptoms. However, in some cases, symptoms of psoriatic arthritis appear before the skin rash of psoriasis. Symptoms of psoriasis may include frequent episodes of redness and itching; thick, dry, silvery scales on the scalp, elbow, knees, or the trunk; and nail abnormalities.
Because psoriatic arthritis closely resembles rheumatoid arthritis, a blood test to check for rheumatoid arthritis is required to make an accurate diagnosis. Tests for rheumatoid arthritis are usually normal (negative) in patients with psoriatic arthritis. People with psoriatic arthritis may have a mild anemia. Blood tests can also reveal an elevated erythrocyte sedimentation rate (ESR), a marker of inflammation.
A definitive diagnosis of psoriatic arthritis cannot be made until skin and nail changes associated with psoriasis appear or until characteristic X-ray changes in the bones of the hands or feet develop.
Psoriatic Arthritis Treatment
Psoriatic arthritis treatment is intended to relieve the symptoms of the disorder and may include any combination of the following:
Non-steroidal anti-inflammatory drugs (NSAIDs) can provide long-term relief from chronic pain and inflammation. NSAIDs work by blocking the production of certain body chemicals that cause inflammation. There are many different NSAIDs to choose from and your doctor may have to try several to find the right one for you.
Long-term use of NSAIDs can cause stomach irritation, ulcers, and even bleeding by inhibiting the production of the stomach's protective mucus layer. Cytotec (misoprostol) reverses this effect on the stomach, so some doctors recommend taking this medication along with NSAIDs. Other doctors prefer to protect the stomach by giving stomach acid blockers (proton pump inhibitors such as omeprazole). However, not everyone will need something to protect the stomach.
Corticosteroids (commonly referred to as steroids) are powerful anti-inflammatory drugs that can be taken by mouth or injected directly into a joint or muscle to relieve severe pain and inflammation. They are chemically different from the muscle-building type of anabolic steroids.
Prednisone is the steroid most commonly used to treat certain rheumatic diseases. However, steroids are used only when absolutely needed because long-term use may cause serious side effects such as bone deterioration and joint weakness.
Disease modifying anti-rheumatic drugs (DMARDs) have been shown to slow the progress of psoriatic arthritis. Available only by prescription, DMARDs are more powerful, yet slower acting, than NSAIDs and must be closely monitored by a doctor for side effects. DMARDs that are used to treat psoriatic arthritis include methotrexate and sulfasalazine. Newer drugs, known as biologicals, target inflammation-causing substances that can lead to worsening of the disease. Enbrel, Humira, Remicade, and Simponi are examples of these drugs.
Moderate, regular exercise may relieve joint stiffness and pain associated with psoriatic arthritis. A tailored program of range-of-motion and strengthening exercises, combined with cardiovascular exercise, can help:
- Relieve arthritis symptoms.
- Maintain normal joint movement.
- Increase flexibility and muscle strength.
- Maintain weight to reduce pressure on joints.
- Improve endurance and cardiovascular fitness.
Hydrotherapy or aqua therapy (water therapy) is a program of exercises performed in a large pool. Aqua therapy may be easier on painful joints from psoriatic arthritis because the water takes some of the weight off the affected areas. Appropriate recreational exercise also may be beneficial, but only if it is preceded by a program of range-of-motion, strength, and aerobic exercises to reduce the chance of injury. Regardless of the exercise program you select, it's important to choose one you enjoy so that you maintain it.
Before beginning any new exercise program, discuss exercise options with your doctor. Also, begin new exercise programs under the supervision of a physical therapist or qualified professional, preferably one who has experience working with arthritis patients.
Improper exercise programs may make psoriatic arthritis worse. Check with your doctor or therapist and adjust your program if you experience any of the following:
- Unusual or persistent fatigue
- Increased weakness
- Decreased range of motion
- Increased joint swelling
- Continuing pain (lasting more than an hour after exercising)
Heat and Cold Therapy
Heat and cold therapy involves alternating moist heat and cold to affected joints to provide temporary relief of pain and swelling associated with psoriatic arthritis. Moist heat -- supplied by a warm towel, hot pack, warm paraffin bath, or a simple warm bath or shower -- can help relax aching muscles and relieve joint pain and soreness.
Your doctor also may recommend ultrasound therapy for deep heating in some joints, depending on your condition.
Cold therapy -- supplied by a bag of ice or even frozen vegetables wrapped in a towel -- can reduce swelling and relieve pain by numbing the affected joints.
Joint Protection and Energy Conservation
Daily activities should be performed in ways that reduce excess stress and fatigue on joints. Proper body mechanics (the way you position your body during a physical task) may not only protect joints, but also conserve energy. People with psoriatic arthritis are encouraged to frequently change body position at work, at home, and during leisure activities. Maintaining good posture -- sitting and standing up straight and not arching the back -- also is valuable for preserving function.
Three techniques can help distribute workloads and stress throughout the body to prevent overworking affected joints:
- Pacing. Alternate heavy, hard, or repetitive tasks with light or easy tasks, or with breaks from the activity.
- Conservative joint use. Use joints in a manner that produces the least amount of stress on them, such as using larger, stronger joints in place of smaller ones whenever possible. For example, use a shoulder bag rather than a hand-held purse.
- Assistive devices. A variety of helpful devices, such as canes, grab bars, extra-thick pens, luggage carts, or sit/stand stools can relieve stress on joints and make daily activities more comfortable. An occupational therapist can help you select devices that are appropriate for your type of psoriatic arthritis.
Your doctor may recommend splinting to help with inflammation or problems with joint alignment or stability. Splints also can help minimize joint destruction that can be seen with psoriatic arthritis. Wrist or finger splints may help rest joints at night or hold them in a comfortable position during work or exercise. However, joints should not be totally immobilized. Splints should be removed periodically to perform gentle range-of-motion exercises to maintain mobility in those joints.
Most people with psoriatic arthritis will never need surgery. However, when all other treatments fail, a surgical procedure called synovectomy may be required to restore joint function or remove diseased portions of the joints. Severely damaged joints may require arthroplasty or joint replacement surgery, in which natural joints are replaced with artificial ones to restore function in the affected area. Joint fusions also may be needed to take care of pain that doesn't respond to medications. Surgery also may relieve pain, increase movement, or improve the physical appearance of the affected area.