Psoriatic arthritis (PsA) is a type of arthritis that occurs in people with psoriasis. Psoriasis is a skin disease where itchy, scaly red patches appear on the skin and scalp. According to The National Psoriasis Foundation (NPF), about two percent of the United States population has psoriasis. (NPF) Between 10 and 30 percent of psoriasis patients develop PsA.
PsA can be mild or severe, involving one or many joints. It’s most likely to occur in people between the ages of 20 and 50. The cause of PsA is unknown. However, genes are thought to play a role.
There are five types of PsA.
Symmetrical PsA occurs in the same joints on both sides of the body. It can resemble rheumatoid arthritis (RA). However, it tends to be milder and cause less joint deformity than RA. Symmetrical PsA can be disabling.
Asymmetrical PsA affects a joint or joints on one side of the body. Joints may feel sore and appear red. Asymmetrical PsA is generally mild.
Distal interphalangeal predominant (DIP) PsA involves the joints closest to the nails. These are known as the distal joints. It only occurs in five percent of cases. However, DIP is considered a classic form of PsA.
Spondylitis PsA involves the spine. The entire spine from the neck to the lower back may be affected. This can make movement very painful. The hands, feet, legs, arms, and hips may also be affected with spondylitis PsA. Inflammation of the spine is the main symptom in five percent of people with PsA.
Arthritis Mutilans is a severe, potentially deforming type of PsA. Less than five percent of people with PsA have this type. Arthritis mutilans usually affects the hands and feet. Pain may also be present in the neck and lower back.
Symptoms of PsA include:
- morning stiffness
- scaly skin patches – these may get worse when arthritis flares up
- nail pitting
- separation of the nail from the nail bed
- swollen, tender joints
- painful muscles and tendons
- eye redness and pain
Diagnosing PsA requires eliminating other causes of arthritis, such as RA and gout. This can be done with several tests.
- Rheumatoid factor (RF) is an antibody that can be present in rheumatoid arthritis. It is usually negative in PsA. A blood test can help doctors distinguish between PsA and RA.
- X-rays of the hands can check for a “pencil-in-cup” appearance. This shows where inflammation has worn down the ends of the bone. This symptom usually occurs later in the development in PsA.
- Microscopic examination of joint fluid can rule out gout. Uric acid crystals aren’t present in PsA.
The goal of PsA treatment is to improve symptoms of skin disease and joint inflammation. A number of different types of medication can be used.
Nonsteroidal anti-inflammatory drugs (NSAIDs) help to control joint pain and swelling. They are the first line of treatment for PsA. Ibuprofen (Advil, Motrin) and naproxen (Aleve, Anaprox) are over-the-counter NSAIDs. These work for many people. However, prescription NSAIDs allow for higher doses. NSAIDS can cause stomach irritation and bleeding. They should be taken with food.
Disease-modifying antirheumatic drugs (DMARDs) are different from NSAIDs. They don’t just reduce pain and swelling. They also limit the extent of joint damage. These medications act slowly. It may take weeks or months to notice an improvement. Methotrexate (Trexall) and sulfasalazine (Azulfidine) are examples of DMARDs. Methotrexate provides the most improvement, but its side effects include liver, lung, and kidney problems. DMARDs have not yet been proven to cause PsA remission.
Immunosuppressants suppress the immune system to decrease joint inflammation. Cyclosporine (Sandimmune, Neoral), Leflunomide (Arava), and Azathioprine (Imuran, Azasan) can all be used to treat PsA. Immunuosuppressants can have negative side effects, such as anemia and low white blood cell count. These medications are also used to prevent transplant rejection.
Anti-TNF alpha drugs block the effects of the protein TNF-alpha. This reduces inflammation and improves the symptoms of psoriasis. Side effects of these medications can be very serious and life- threatening. Talk with your doctor to see if the benefits for taking these medications outweigh the risks. Some examples of these drugs are:
- Enbrel (Etanercept)
- Humira (Adalimumab)
- Remicade (Infliximab)
- Simponi (Golimumab)
There are things you can do at home to help improve your symptoms.
Eat a balanced diet and maintain your best weight. Obesity aggravates arthritis and can make movement more difficult. Talk with your doctor about planning a diet if you need help losing weight.
Exercise regularly. Being sedentary slows you down and increases the risk of obesity and other diseases. Talk with your doctor about what type of exercise is safe to do daily. Biking, walking, swimming, and other water exercises are gentler on the joints than other forms of exercise.
Take your time! Pacing yourself can help prevent discomfort, strain, and injuries.
Use hot and cold packs. Warm compresses and hot packs can help muscle soreness. Cold packs applied to joints can reduce pain.
Move in ways that protect your joints. Open doors with your body instead of your fingers. Lift heavy objects with both hands. Use jar openers to twist jar lids.
Symptoms of PsA can recur. Early diagnosis and treatment can help reduce pain and joint damage.