Psoriatic arthritis is a form of joint inflammation that occurs in people with a skin condition known as psoriasis: an autoimmune disease in which some skin cells are produced more rapidly than normal, to form red, scaly patches.
The most common form of psoriatic arthritis involves the small joints of fingers and toes, but other joints such as the ankles, jaw, spine can be affected, too.
An estimated 1 in 50 people (2%) have psoriasis, of whom between 20% and 40% also develop psoriatic arthritis - usually within 10 years of having psoriasis diagnosed.1, 2
There doesn't seem to be a link between the severity of skin psoriasis and the risk of developing arthritis, and why some people develop it and others do not is not fully understood. There does seem to be a genetic link, however, as up to half of people with psoriatic arthritis have a family history of the condition.
What are the symptoms?
The symptoms of psoriatic arthritis are similar to those of other inflammatory joint conditions such as rheumatoid arthritis. In psoriatic arthritis, affected joints become tender, swollen, painful and stiff, especially on waking in the morning. Tendons which bind muscles to bone are lubricated by a synovial membrane and can become inflamed, too, causing muscle tenderness especially around the elbows, wrists and heels. In severe cases, joints may lose their range of movement and become misshapen or locked, although this is less common thanks to the development of powerful new disease-modifying drugs.
Fatigue is another common problem associated with inflammation, and you may feel exhausted or tired most of the time. Researchers do not know exactly what causes persistent fatigue, but it seems to be linked with increased levels of immune complexes and other inflammatory substances in the body.
Some people with psoriatic arthritis notice pitting (small dimples) on their nails, or nail thickening and discoloration. Inflammation of a part of the eye (uveitis or iritis) can also lead to pain and redness of one or both eyes which needs immediate medical treatment.
How is psoriatic arthritis treated?
Psoriatic arthritis is a long-term (chronic) problem in which symptoms tend to flare up from time to time. Several different types of drugs are used to help control symptoms, such as non-steroidal-anti-inflammatory drugs, corticosteroid injections into, or around, a single painful joint, and disease-modifying drugs (e.g. methotrexate) which switch off the immune reactions that are causing inflammation and pain. New treatments, known as biological drugs, block the effects of immune substances, such as TNF alpha, to help reduce damage to joints and to reduce symptoms.
Self help
If you have received a diagnosis of psoriatic arthritis, a number of diet and lifestyle approaches may help.
Weight
Aim to lose any excess weight by following a healthy, balanced diet to relieve inflammation throughout the body and reduce strain on weight-bearing joints. A Mediterranean style diet providing plenty of fruit and vegetables is especially helpful.
Regular exercise is key
Take regular, gentle exercise to help reduce muscle weakness and joint stiffness. If inflammation makes you feel more tired than usual, take regular rests. Always rest severely inflamed joints.
Your doctor can refer you to a physiotherapist who specialises in arthritis, who can show you:
- A range of simple exercises to help maintain joint mobility
- Ways to reduce joint pain e.g. ice packs, massage, applying warmth, using a T.E.N.S. (transcutaneous electrical nerve stimulation) machine
- How to use walking aids to protect your joints
An occupational therapist can suggest ways to make life easier using aids such as wrist splints, blocks to raise your chair, a raised toilet seat with arm rests, rails, long or thick-handled tools, a stick, stocking helpers or modified shoes for example.
Don't be afraid to seek help
Psoriatic arthritis has a significant effect on your quality of life and, not surprisingly, can leave you feeling anxious and depressed. If you are experiencing problems, or feel low in yourself, it's important to see your doctor so they can help you find solutions.
New treatments are available, and you may benefit from a review of your medication if pain or fatigue are interfering with your mobility or ability to function as well as you would like.