Psoriatic arthritis (PsA) and psoriasis are types of psoriatic disease. PsA causes joint pain and stiffness, and psoriasis mainly involves the skin, but they often occur together.

Around 2 in 10 people with psoriasis will develop PsA. There are different types of psoriasis, but plaque psoriasis is the most common type, affecting 80–90% of individuals with skin symptoms.

Both conditions are long term. Psoriasis becomes more aggravating during flares and can worsen over time if left untreated.

PsA can cause joint damage, leading to permanent damage. It often worsens over time, but the outlook will vary between individuals.

This article explores the link between psoriasis and PsA. It also looks at the causes, symptoms, and treatments of each condition.

hands of person with psoriasis and psoriatic arthritisShare on Pinterest
Both psoriasis and psoriatic arthritis can affect the hands.
Mediscan/Alamy Stock Photo

While psoriasis and PsA are related, they are separate conditions. They are part of psoriatic disease, an immune-mediated inflammatory condition.

Immune responses that lead to inflammation in the body cause the symptoms of both conditions:

  • In plaque psoriasis, inflammation causes skin cells to renew too quickly, resulting in a scaly rash on the skin with characteristic silvery plaques.
  • In PsA, inflammation causes joint pain and stiffness. It can affect one joint or more and may lead to long-term joint damage.
  • In both conditions, a person may also have eye inflammation, known as uveitis, and pitted or crumbling psoriatic nails.

Psoriasis and PsA often affect the same people, but not always.

Experts do not know precisely how many people with psoriasis will develop PsA, but research has suggested it is between 6% and 41%.

Of these, 68% will have psoriasis before PsA symptoms appear. In around 15% of individuals, symptoms of psoriasis and PsA appear at the same time. In 17% of those with PsA, arthritis occurs before skin symptoms.

Meanwhile, some people have PsA without psoriasis.

Scientists believe up to 15.5% of individuals with psoriasis have PsA but without a diagnosis. Some researchers have noted that blood tests to measure C-reactive proteins (CRPs) may help distinguish between PsA and psoriasis and show if an individual has one or both conditions.

The severity of psoriasis does not predict whether someone will develop PsA.

Both psoriasis and PsA can:

  • cause discomfort
  • affect a person’s quality of life
  • affect their mental health and self-esteem

People with PsA, psoriasis, or both may also have a higher risk of metabolic syndrome, including:

Treatment for PsA and psoriasis can help ease symptoms and reduce the risk and severity of flares. Some treatments are similar, such as the use of biologic drugs. However, some target PsA or psoriasis specifically.

Psoriasis and PsA are related but differ in many ways.

Common symptoms of PsA include joint pain, stiffness, and distinctive features such as “sausage-like” fingers, while psoriasis primarily presents with itchy, silvery skin plaques.

Diagnosis for PsA usually involves a process of elimination and includes a thorough:

Treatment approaches also differ, with PsA often requiring systemic drugs such as biologics and methotrexate, while psoriasis management leans toward topical treatments and light therapy.

This table shows some similarities and differences between PsA and plaque psoriasis, the most common form of psoriasis.

Plaque psoriasis and PsAPlaque psoriasis onlyPsA only
Causes and risk factors • inflammation
• genetic factors
• a history of psoriatic disease
• physical trauma to the skin• a personal history of psoriasis, especially with nail psoriasis or uveitis
• a family history: 33–50% of people with PsA have a close relative with psoriatic disease
• psoriasis affecting a large proportion of the skin
• some medications
alcohol and tobacco use
• infections that involve inflammatory processes
• physical trauma to the skin
• exposure to sunlight
• infections
• physical trauma to a joint
• heavy lifting
• infectious diarrhea
Common symptomsuveitis
nail psoriasis
• itchy, silvery plaques on the skin
• other skin changes for other types of psoriasis
• joint pain and stiffness
• swollen, or “sausage,” fingers or toes (dactylitis)
• inflammation in tendons and ligaments where they meet a joint (enthesitis)
• back pain (spondylitis or axial PsA)
DiagnosisFor both PsA and psoriasis, the doctor may screen for conditions that commonly occur with psoriatic diseases, such as obesity and other aspects of metabolic disorder. A doctor will:
• ask the person about their symptoms and family history
• examine the symptoms
• take a skin biopsy to confirm psoriasis
The doctor will most likely:
• ask about symptoms
• ask about any history of psoriatic disease in the individual or their family
• do a physical examination, including checking for dactylitis and enthesitis
• recommend imaging tests, such as an X-ray, MRI, or ultrasound scan
• do blood tests to rule out other forms of arthritis or causes of joint pain
Treatment• systemic drugs, such as biologics and methotrexate
• various lifestyle remedies
counseling and treatment for mental health complications
• moisturizers and emollients
topical corticosteroids
• other topical applications
• light therapy
methotrexate injections and pills
nonsteroidal anti-inflammatory drugs (NSAIDs)
• disease-modifying antirheumatic drugs (DMARDs)
methotrexate pills and injections
corticosteroid injections, in some cases
Outlook• lifelong condition
• remission is possible with treatment
• remission occurs in 10–60% of people• can worsen over time
• reduced mobility and functionality
Complications• physical discomfort
• reduced quality of life
• higher risk of cardiovascular problems
• negative effect on mental health
• adverse effects of treatment
• severe itching
• secondary infections
• effect on physical appearance
• reduced mobility
• chronic pain
• higher risk of metabolic syndrome, including obesity and type 2 diabetes
• changes to the shape of fingers, toes, and joints

It is not always possible to prevent psoriasis or PsA, but some measures may help reduce the risk of flares or more severe symptoms.

Some tips a person can consider include:

It is also important for people with psoriasis to:

  • cover the skin and hydrate well in cold weather
  • avoid sun exposure and use air conditioning in warm or sunny weather
  • bathe or shower in warm water, not hot water

Can herbs help manage psoriasis?

Here are some questions about psoriasis psoriasis vs psoriatic arthritis.

Are psoriatic arthritis and psoriasis the same?

Both conditions are psoriatic diseases. A person who has psoriatic arthritis will often have psoriasis, but they are not the same disease. PsA affects the joints, but psoriasis causes skin lesions.

Which comes first, psoriasis or psoriatic arthritis?

In 68% of cases, psoriasis comes first. In around 15% of people, symptoms of psoriasis and PsA appear at the same time, but 17% of individuals with PsA develop arthritis before skin symptoms. Not everyone with PsA has psoriasis.

What are the early signs of psoriatic arthritis?

A person who develops PsA may already have nail psoriasis and skin symptoms. Early signs of joint involvement include swelling in the fingers, toes, or both, known as dactylitis. There may also be pain and tenderness where the tendons and ligaments meet a joint, known as enthesitis.

Can you have psoriasis without psoriatic arthritis?

It is common to have psoriasis without psoriatic arthritis. Research suggests only 20% of people with psoriasis will develop psoriatic arthritis.

Psoriasis and PsA are both types of psoriatic disease. They are immune-mediated, and symptoms occur due to inflammation. They are different diseases but have several factors in common.

Psoriasis causes skin symptoms, but PsA causes pain and stiffness in one or more joints. However, people with PsA often also have psoriasis.

A person with either condition can have uveitis, an eye infection, or nail psoriasis. People with both nail psoriasis and skin symptoms may have a higher risk of developing PsA.

Treatment is available for both conditions. Some therapies are the same for both, while others are specific to the disease. PsA and psoriasis are lifelong conditions, but treatment can help move them into remission, when symptoms improve or resolve for a while.