Psoriatic arthritis is characterized by tenderness and inflammation of the joints. It is often associated with psoriasis. But there is much more to know about psoriatic arthritis.

Psoriatic arthritis is a chronic, inflammatory disease that affects the body’s joints and connections between the tendons, ligaments, and bones.

Symptoms of psoriatic arthritis include fatigue, pain in joints, swelling around joints, tenderness, stiffness, and throbbing.

People with psoriatic arthritis also experience a second set of symptoms: rashes and dry, flaky patches of skin called plaques. Psoriasis, an inflammatory skin condition, causes these plaques.

Read on to learn more about psoriatic arthritis, what causes it, and who is most likely to develop it.

The symptoms of psoriatic arthritis are sometimes vague. They can also resemble other conditions.

Doctors may first attribute the symptoms to other forms of arthritis or inflammatory conditions, such as osteoarthritis or gout.

Confirming a diagnosis may take several rounds of physical exams and lab tests.

Psoriatic arthritis is an immune-mediated condition with autoimmune features. With psoriatic arthritis, the immune system attacks the joints and skin.

It can also affect other tissues, including organs. Chronic inflammation in healthy tissue results in symptoms such as pain, swelling, inflammation, and stiffness.

Rheumatoid factors (RF) are proteins the immune system produces. They can form complexes with other proteins that can attack healthy cells and tissue.

Most people with psoriatic arthritis are RF-negative. A blood test will not detect any RF proteins.

If a blood test is positive for RF, a doctor may suspect rheumatoid arthritis is causing arthritis symptoms, not psoriatic arthritis.

No single diagnostic test can confirm a psoriatic arthritis diagnosis. Instead, a doctor uses multiple tests.

These tests include X-rays and MRIs to look for changes in the bones and joints. Blood tests, such as sedimentation rate and C-reactive protein, can detect signs of inflammation.

A skin biopsy can also confirm whether psoriasis is causing red, patchy scales.

Psoriatic arthritis can be a progressive condition. There is no cure. Most people with the condition experience occasional periods when symptoms and disease activity are elevated. These periods are called flares.

People can manage most flares with medication and lifestyle strategies until the symptoms return to pre-flare levels.

Having a family member with psoriatic arthritis can increase a person’s chances of developing psoriatic arthritis.

In fact, about 40% of people with psoriatic arthritis have at least one close family member with either psoriatic arthritis or psoriasis, according to a 2020 study. However, not every person with the condition has this family connection.

According to a 2021 study, 7.5 million people ages 20 years and over have psoriasis in the United States.

However, only about 30% of those people will develop psoriatic arthritis, suggests a 2013 study. Most people with psoriasis will not develop the related arthritis condition.

People with psoriasis can develop other types of arthritis, including osteoarthritis. Some may develop rheumatoid arthritis, but this is rare.

Men and women are equally likely to develop psoriatic arthritis. The condition can start at any age. However, most people receive a diagnosis between 30 and 50 years old.

People also receive their diagnosis about 7 to 10 years after the onset of psoriasis skin symptoms.

Psoriatic arthritis may be hereditary, but it is not contagious. It cannot be passed from person to person.

But outside events, such as an injury, stress, or illness, may make people predisposed to the condition more likely to develop their first symptoms.

When the immune system is pressed into action by one of these triggers, a side effect may be the autoimmune response that causes psoriatic arthritis to develop.

Psoriatic arthritis is not limited to commonly affected joints, such as in the hands, feet, arms, or legs. It can also affect the joints of the spine, hips, and shoulders.

Any joint where ligaments and tendons connect to bones is susceptible to arthritis symptoms.

The immune system’s attack on healthy tissue affects more than the joints. People with psoriatic arthritis may also experience symptoms in other body parts, including inflammation of the eye (uveitis) and digestive tract (inflammatory bowel disease).

Additionally, people with psoriatic arthritis are more likely to develop conditions such as depression and metabolic syndrome. Metabolic syndrome is a cluster of conditions that occur together, such as heart disease, diabetes, and stroke.

Treating psoriatic arthritis early and aggressively can help reduce the chances of this type of permanent damage.

While there is no cure for psoriatic arthritis, a range of treatments, including over-the-counter and prescription medications, can help ease symptoms.

Treatment can help slow the progression of psoriatic arthritis, reduce flares, and protect joints and tissue from long-term damage.

While the impact of psoriatic arthritis can be widespread, with an effective treatment plan, the condition does not have to lead to poor health.

Not every person with psoriatic arthritis will show signs of the condition, such as swollen fingers, sometimes called “sausage fingers,” or red, scaly patches on the skin.

Many symptoms of psoriatic arthritis are invisible. This can make the pain and fatigue difficult to explain to others.

In addition to medication, some people find symptom relief with physical activity. Biking, yoga, and walking can all help improve joint strength, flexibility, and stamina.

Physical activity may also help reduce the risk of conditions such as high blood pressure, type 2 diabetes, and obesity.

Psoriatic arthritis is a progressive, chronic condition. Early and aggressive treatment can prevent some of the worst complications of the condition, including long-term damage to the joints and organs.

Additionally, lifestyle strategies may help ease some symptoms and make living with the condition easier.