An Expert's Perspective on Treating Psoriatic Arthritis
Psoriatic arthritis is an autoimmune disease, a type of disease where the immune system attacks healthy tissue. In the case of psoriatic arthritis, a form of inflammatory arthritis, the body’s immune system attacks healthy joints and, often, skin. These attacks trigger pain, swelling, and stiffness. People with psoriatic arthritis most likely often also have psoriasis, a skin condition that causes red, scaly patches to form on the body and can cause the nails to lift from their nail beds. In most cases, people have psoriasis first before psoriatic arthritis presents, although sometimes they develop it after a diagnosis of psoriatic arthritis. Still, some psoriatic arthritis patients don’t develop psoriasis at all. It varies from person to person.
Psoriatic arthritis, like all forms of inflammatory arthritis, is difficult to diagnose. However, it’s important to get a diagnosis early and to start treatment as soon as possible to prevent worsening or permanent joint damage. Rheumatologist Erin Arnold, MD, discusses the most common questions she gets about treating psoriatic arthritis.
1. Q: What are the symptoms of psoriatic arthritis?
A: Joint pain, swelling, and stiffness are the symptoms of most arthritis conditions. With psoriatic arthritis, the pain and stiffness are usually present for prolonged periods in the morning. Which joints are most affected can help us determine if it’s psoriatic arthritis as opposed to another type of inflammatory arthritis, such as rheumatoid arthritis, arthritis that also affects joint linings. The following joints are commonly affected by psoriatic arthritis:
Other symptoms of psoriatic arthritis may include:
Swelling of fingers and toes contributing to a sausage-like appearance
Enthesitis, which is tenderness or pain where tendons or ligaments attach to bones
Reduced range of motion
2. Q: How is psoriatic arthritis diagnosed?
A: When diagnosing psoriatic arthritis in my patients, I look for many things. First, I listen to the patient’s story. Does he or she have pain and stiffness in the morning, swollen joints, and psoriasis? Then, I perform a physical exam to look for swollen joints, test for range of motion, and check for signs of psoriasis. I will also take a blood test to look for an inflammation marker such as ESR (erythrocyte sedimentation rate) or C-reactive protein in the blood. However, that is often not abnormal. In certain situations, I use imaging devices such as magnetic resonance imaging (MRI) or ultrasound to show inflammation and I take X-rays to look for changes in bones. With this information, I’m able to make an accurate diagnosis and develop a treatment plan that meets the patient’s individual needs.
3. Q: What options are available for treating psoriatic arthritis?
A: It’s a very exciting time to be treating patients with psoriatic arthritis. In the last two years, science has made great strides in developing treatment options for psoriasis and psoriatic arthritis. Initially, I start most patients on some type of anti-inflammatory such as ibuprofen (Advil) or diclofenac (Voltaren). If I find significant inflammation and damage to the joints, I add medication that will reduce or eliminate symptoms and ultimately prevent the disease from progressing. These treatment options include:
Disease-modifying antirheumatic drugs (DMARDs), such as methotrexate (Rheumatrex) and sulfasalazine (Azulfidine), help reduce symptoms and help prevent joint damage.
Corticosteroids, such as dexamethasone, can be used for severe pain and inflammation and are injected directly into problem joints for a fast-acting, but short-term treatment. These drugs are not used as a long-term treatment because of their adverse side effects, such as cataracts, high blood pressure, and headaches.
Biologic TNF inhibitors, such as adalimumab (Humira) and etanercept (Enbrel), block a protein called tumor necrosis factor (TNF) that promotes inflammation in the body. Biologics are technically a subset of DMARDs.
Biologic IL-12/23 inhibitor, a biologic treatment recently approved to treat psoriatic arthritis, blocks two proteins in the body that cause inflammation: interleukin 12 (IL-12) and interleukin 23 (IL-23). The first of this type of drug, ustekinumab (Stelara), treats both joint inflammation and skin flare-ups.
Biologic IL-17 inhibitor, secukinumab (Cosentyx), is the newest drug to get approved by the U.S. Food and Drug Administration (FDA)l to treat psoriatic arthritis. This drug is also approved to treat psoriasis and ankylosing spondylitis (also known as spinal arthritis), which are sometimes also present with psoriatic arthritis.
Apremilast (Otezla), also a newer treatment, is not considered a biologic but does block an enzyme known as phosphodiesterase 4 (PDE4) that causes inflammation.
4. Q: What lifestyle changes can patients make to improve their psoriatic arthritis?
A: I try to emphasize to my patients that lifestyle changes are complementary to taking their medications; they're not in exclusion of each other. Physical therapy can be helpful, especially joint-specific exercises that focus on symptoms such as neck, hip, knee, or foot pain. I recommend taking omega-3 fatty acids in the form of fish oil to help treat inflammation. Also, vitamin D supplements can help maintain bone strength and reduce inflammation.
As far as diet goes, I offer my patients advice on foods that are rich in omega-3s. Since sugar and red meat can aggravate symptoms, I stress the importance of eliminating those things from their diets.