Psoriatic Arthritis Causes and Treatments

About 20 percent of people with psoriasis develop psoriatic arthritis, though researchers have not identified why this is. According to the National Institutes of Health, people with psoriasis who develop psoriatic arthritis see the onset of the arthritic symptoms about seven to ten years after their skin symptoms appear.

Some researchers believe that psoriatic arthritis may result from elevated systemic inflammation, leading to psoriasis symptoms spreading beyond the skin. Research also shows that people with psoriasis and major depressive disorder are more likely to develop psoriatic arthritis.

As many as 50 percent of people with psoriatic arthritis or psoriasis have a first-degree relative who also has one or both of these conditions, hinting that there is a strong genetic factor at play. Although psoriasis seems to predispose people to psoriatic arthritis, the genetics of the two conditions are not identical.

People can get psoriatic arthritis without having psoriasis. Researchers have identified specific genes associated with psoriatic arthritis that are unrelated to psoriasis and vice versa, which means that, in some cases, psoriatic arthritis has its own genetic cause. Researchers have also identified genes associated with specific types of psoriatic arthritis.

The environment likely plays a role in psoriatic arthritis, too. Researchers believe that a complex interaction between genetic and environmental factors is at play in many cases, though this has been challenging to confirm. Various studies have shown links between psoriatic arthritis and strep infections, antibiotic use, and skin trauma.

Anyone can develop psoriatic arthritis, but it most commonly occurs in adults between 30 and 55. Age adds another level of complexity to the diagnosis, partly because older people are more likely to have comorbidities or other medical conditions that can affect the progression and severity of the disease and the response to treatment.

Symptoms of psoriatic arthritis wax and wane; the most intense periods are called flare-ups. While the cause of the condition is unclear, the possible causes of flare-ups have been easier to identify.

The most common causes of flare-ups are stress, dry skin, sunburn, skin trauma, climate, eating gluten, and drinking alcohol. Common infections can lead to flare-ups, as can some medications, like beta blockers and antimalarial drugs.

Nonsteroidal anti-inflammatory drugs or NSAIDs are generally used for mild symptoms of psoriatic arthritis, particularly for people who are newly diagnosed. These medications are commonly available over the counter, but doctors can prescribe them in higher doses. NSAIDs may not work for everyone with the condition, particularly those with advanced disease.

Corticosteroids are anti-inflammatory drugs that can lessen swelling in psoriatic arthritis, particularly for dactylitis, a severe inflammation of the fingers or toes that occurs in as many as 50 percent of people with the condition. Doctors inject corticosteroids directly into the membrane around the joint, providing targeted relief.

These medications can be used on their own or in conjunction with other drugs.

Disease-modifying anti-rheumatic drugs (DMARDs) treat psoriatic arthritis and other inflammatory conditions, including rheumatoid arthritis and ankylosing spondylitis. Each drug in this class works differently, but they all aim to disrupt the inflammatory process.

DMARDs can have a range of adverse effects, the most significant being the increased risk of serious bacterial, viral, and fungal infections. DMARDs are often used when NSAIDs are no longer effective.

Tumor necrosis factor inhibitors or TNF inhibitors are a class of drug that inhibits tumor necrosis factor, which is produced in the body and contributes to multiple inflammatory conditions. These medications are given by IV or injected under the skin.

Although they are generally well-tolerated, they may have significant adverse effects, the most common being an increased risk of severe infection.

Psoriatic arthritis can affect daily life, but some lifestyle changes can improve mobility and reduce flare-ups.

Some studies show that smoking can affect treatment outcomes, so people with psoriatic arthritis should not smoke. Maintaining a healthy weight puts less pressure on the joints, which can help relieve pain; doing low-impact exercises, like cycling or swimming, can help with mobility.