Psoriasis is a chronic, inflammatory condition that can involve changes to the skin and the joints. When it affects the joints, this is psoriatic arthritis.
PsA is a form of arthritis that can affect people with psoriasis. Psoriasis and psoriatic arthritis result from a problem with the immune system. There is growing evidence of a link between the two conditions, and doctors refer to them jointly as psoriatic disease.
A person who has psoriasis with skin involvement may also develop psoriatic arthritis (PsA).
The most common symptoms of PsA are:
Swollen and painful joints
PsA can lead to pain and swelling in any joint in the body. The joints may also be red and warm to the touch.
PsA often affects the hands, fingers, feet, toes, knees, ankles, and spine. It can also affect the neck and wrists. A person may also experience pain in the lower back.
PsA in the finger usually affects the joint closest to the nail.
Swelling in arthritis happens when either the lining of the joint or the fluid that surrounds the joint increases in volume. When this happens, more blood enters the area around the joint, which increases pressure and causes redness and swelling.
Symptoms can vary in severity between people. In some people, arthritis may affect one or two joints, but others might experience severe changes throughout the body.
Stiffness and reduced movement
Many people experience stiffness, particularly in the morning or after rest. It can occur with or without pain and in any joint and can limit movement.
Although stiffness is a widespread problem, stiffness that continues for longer than an hour could be a sign of inflammatory arthritis, such as PsA.
PsA, like other types of inflammatory arthritis, can lead to fatigue.
Around 29% of people with PsA report experiencing severe fatigue and 50% have moderate to severe fatigue, according to an article published by the National Psoriasis Foundation.
PsA can trigger changes in the finger and toenails, signs of nail psoriasis.
- pits, or small depressions
- detachment from the nail bed
If the nail detaches, a person may develop onycholysis, an infection that resembles a fungal infection.
A person with psoriasis who notices changes in their nails should speak to their doctor, who may suggest screening for PsA.
Swollen fingers and toes
One symptom that is specific to PsA is dactylitis, which causes swollen, "sausage-like" fingers and toes.
According to one source, psoriasis often appears during childhood or young adulthood, and PsA usually develops between the ages of 30–50 years.
The National Psoriasis Foundation note that PsA often begins around 10 years after skin symptoms appear.
The foundation also indicate that 10–30% of people with psoriasis will develop PsA.
Authors of a 2016 study noted that 85% of cases of PsA start before the age of 40 years.
They added that 70% of people with PsA experience skin changes before the symptoms of PsA appear, while 15% of people develop skin changes after having symptoms of PsA for around 2 years. Other people may develop both at the same time.
However, both can appear at any time of life.
PsA can have a significant impact on a person's life, with 40% of people describing it as a "large" problem for them.
Genetics Home Reference note that there are five types of PsA:
- distal interphalangeal predominant
- asymmetric oligoarticular
- symmetric polyarthritis
- arthritis mutilans
These have slightly different symptom patterns, and they vary in severity.
Asymmetric oligoarticular and symmetric polyarthritis are the most common types.
About 5% of people with PsA will develop arthritis mutilans, which is the least common and the most severe form of PsA.
PsA can lead to joint damage, reduced mobility, and depression.
People with psoriatic disease may also have a higher risk of having or developing:
- cardiovascular disease
- nonalcoholic fatty liver disease
If people notice symptoms of these conditions, they should speak to their doctor.
Current guidelines for the treatment of psoriasis recommend regular screening for these conditions, as they can affect the life expectancy and quality of life of a person with PsA.
What is the link between weight gain and PsA? Learn more here.
A person should see a doctor if they have any new or worsening signs of psoriasis or PsA. If a person has psoriasis, and there is a family history of psoriatic disease, the doctor may recommend testing for PsA.
Learn more here about X-rays and other tests for PsA. /articles/316797.php
If tests show that a person has PsA, a doctor may prescribe a drug known as a tumor necrosis factor inhibitor (TNFi), a type of biologic therapy.
Guidelines published in 2018 recommend TNFi as a first-line treatment for people with a new diagnosis of PsA. There is evidence that these drugs can help reduce the risk of flares and the severity of symptoms, and it may slow the progress of the condition.
These drugs may not suit everyone, however, and the decision will depend on the individual's situation.
Other treatments include topical applications, steroid injections, and oral medications and injections that work throughout the body. Lifestyle choices include following a healthful diet, avoiding smoking, and low-impact exercise.
The severity of PsA can range from mild to severe, and it can lead to joint damage and reduce a person's quality of life.
However, new treatment options are proving effective for managing the condition, especially if the person begins therapy in the early stages.
How do I know if I have PsA or rheumatoid arthritis?
In the early stages of both PsA and rheumatoid arthritis, it can be difficult to tell them apart. In either case, you will need to consult a rheumatologist to help identify which arthritis type you have.
Blood tests can help identify one or the other, but this is not always conclusive. Time will eventually show which type you have, as PsA may involve psoriasis plaques on the body or “sausage digits,” and RA will likely have symmetrical arthritic locations, which means it may affect both hands instead of one.Debra Sullivan, PhD, MSN, RN, CNE, COI Answers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.