Psoriasis is a skin disease in which skin cell turnover is faster than the usual cycle. This results in notable red and silvery skin patches that are often itchy and inflamed.

Psoriatic arthritis (PsA) is a form of arthritis that causes stiffness and pain in the joints. The majority of people with this condition have psoriasis symptoms first and then develop PsA.

Given the relatively low prevalence of PsA among Americans, it’s easy to confuse PsA with other types of diseases. Check out some common myths surrounding this autoimmune condition, and learn the facts about risk factors, diagnosis, treatment, and self-care.

Yes, PsA is an autoimmune disease in which the body attacks itself. In this type of arthritis, the immune system destroys healthy joint tissues.

Some people with psoriasis later develop PsA, although it is possible to develop PsA first. PsA can affect various joints, and not everyone experiences the same effects.

Fact: About 30% of people with psoriasis develop PsA.

Not everyone with psoriasis will get PsA. In fact, PsA only affects about 30% of people with psoriasis. This means that the majority of people with psoriasis won’t get PsA. It’s possible for some people with psoriasis to develop another type of arthritis, such as rheumatoid arthritis.

It’s important to consider the incidence of autoimmune diseases in your family. Though there’s no single identifiable cause of PsA, genetic predisposition seems to have a role. About 33% to 50% of people with PsA have a close relative who also has psoriasis or PsA.

Fact: PsA affects all age groups.

According to the National Psoriasis Foundation, PsA is the most common in adults ages 30 to 50. Still, PsA can develop in any age group, including children. If you’re under the age of 30, you shouldn’t assume that you can’t get PsA.

PsA typically develops about 10 years after the onset of psoriasis symptoms. PsA is more common in white people than in other ethnicities.

Fact: PsA causes a wide range of symptoms.

PsA symptoms can vary between individuals, making it difficult to diagnose the condition. While some experience topical (skin and nail) symptoms, others might only notice joint pain and stiffness.

The danger in assuming all PsA symptoms are alike is possible misdiagnosis and a subsequent lack of appropriate treatment.

PsA can cause one or more of the following symptoms:

  • skin rashes and scaly patches (also noted in psoriasis)
  • nail deformities
  • eye redness
  • swollen, painful joints
  • difficulty moving and doing everyday tasks
  • morning stiffness
  • waking up tired
  • excessive fatigue throughout the day
  • difficulty sleeping at night (often from joint pain or discomfort)

Fact: PsA can cause flare-ups, along with periods of remission.

PsA is a chronic condition, which means a person will have it for life.

Having a flare-up with joint pain and skin symptoms is common with this disease. If your case is mild, you may also have remission periods in which you don’t notice any symptoms at all.

However, a lack of symptoms merely means that your immune system is dormant in its attacks on cells and tissues. This doesn’t mean that it’s not PsA or that the PsA has suddenly disappeared.

The only way to be sure about the state of your PsA is to get a diagnosis from a rheumatologist. Avoid relying on symptoms alone as a method of self-diagnosis.

Fact: There are five subtypes of PsA.

PsA is currently diagnosed as one of five subtypes. These are based on the severity of the condition, as well as the location of the affected joints. As the disease progresses, patients may be diagnosed from one subtype to another.

The five subtypes include:

  • Oligoarticular: affects one to four joints asymmetrically (on different sides of your body)
  • Symmetric: affects the same joints on both sides of the body
  • Spondylitis: PsA of the spine
  • Distal interphalangeal: primarily affects finger and toe joints and can also cause nail deformities)
  • Arthritis mutilans: a rare form of PsA that mainly causes severe destruction in feet and hand joints

Fact: Early treatment of PsA can prevent disability.

Just as the causes and symptoms of PsA vary, so does the course of the disease. Not every PsA story is the same. Some people experience mild flare-ups and little pain, while others have a more progressive form of the disease where joint damage is widespread. The key to preventing the latter is early detection and treatment.

Early cases of PsA are often diagnosed as oligoarthritis, meaning that between one and four joints are affected. Polyarticular arthritis refers to instances in which at least five joints are affected. The longer the condition is left untreated, the more joints may be affected.

Disability can occur when irreversible damage is done to your joints, and it’s often the cause of a lack of diagnosis and treatment. However, disability is not inevitable.

Working with the right specialists (including dermatologists and rheumatologists), practicing self-care, and leading a healthy lifestyle can all help prevent the debilitating factors of PsA.

Start a conversation with your doctor if you have psoriasis and are concerned about developing PsA. It’s important to know the facts about PsA to avoid misdiagnosis and properly treat your symptoms.