11 Things to Know About Psoriatic Arthritis

Psoriatic arthritis is an autoimmune disease, meaning it occurs when the body’s immune system mistakenly attacks healthy tissue, in this case the joints and skin. The faulty immune response causes inflammation that triggers joint pain, stiffness and swelling. The inflammation can affect the entire body and may lead to permanent joint and tissue damage if it is not treated early and aggressively.

Many people experience frequent periods of increased disease activity and symptoms, called flares, while others have only infrequent flares. Symptoms can include painful, swollen joints; stiffness; swollen fingers or toes; tendon or ligament pain; skin rashes and nail changes; fatigue; reduced range of motion; and eye problems.

Diagnosing psoriatic arthritis can be a tricky process because its symptoms frequently mimic those of other forms of inflammatory arthritis, such as rheumatoid arthritis (RA) and gout. It can also be confused with osteoarthritis (OA), the most common form of arthritis. For a proper diagnosis, your doctor will conduct a physical exam, take an extensive medical history, and run lab tests.

People with PsA are almost always rheumatoid factor (RF)-negative; if blood tests are positive for RF, the doctor will suspect rheumatoid arthritis first. Joint pain in RA is usually symmetrical (felt on both sides of the body), while joint pain in PsA is usually asymmetrical (felt only on one side of the body). Swelling that involves the full length of individual fingers or toes (dactylitis or sausage digit) is likely caused by PsA.

About 30% of people with psoriasis also develop psoriatic arthritis. That means that a majority of people with psoriasis do not get PsA. However, people with psoriasis could also develop another form of arthritis, including osteoarthritis or rheumatoid arthritis.

Unlike many autoimmune diseases, men and women are at equal risk for developing PsA. Age is also not a determinant: while the disease usually appears between the ages of 30 and 55 in people who have psoriasis, it is sometimes diagnosed during childhood.

Experts believe some people may be predisposed to an autoimmune disease like psoriatic arthritis. In fact, studies show a stronger genetic or family link to this particular disease than other autoimmune rheumatic diseases. About 40% of affected individuals have at least one close family member with psoriasis or psoriatic arthritis.

Psoriasis is not infectious, but the disease might be triggered by an infection, such as strep throat. In addition to infections, researchers believe it could be triggered in people who are genetically more susceptible by extreme stress, an injury or an event that makes the immune system go into overdrive.

PsA affects the joints but it may also cause a range of other symptoms, including fatigue, swelling of the fingers and toes and inflammatory eye disease, called uveitis. It also can predispose you to heart disease, depression and metabolic disease. Although PsA can have widespread impact on the body, a diagnosis doesn’t have to mean lifelong poor health.

Some symptoms of psoriatic arthritis are quite visible – namely skin rashes. But many symptoms, such as joint pain and fatigue, are less apparent. Living with a disease that has both subtle and obvious symptoms can be a double-edged sword. When you don’t have any noticeable skin lesions, friends and family might not realize how much pain you’re in.

There are many over-the-counter (OTC) and prescription treatments for psoriatic arthritis. Some treat symptoms of both psoriasis and psoriatic arthritis, while others target either skin problems or joint issues. Many can also modify the disease course by disrupting the overactive immune system. Read more about psoriatic arthritis.