New Guidelines Ease Treatment of Psoriatic Arthritis
Recent recommendations set new benchmarks for the prescription of the right medications for different stages and forms of this disfiguring disease.
The treatment of psoriatic arthritis—a chronic disease that causes a scaly, itchy skin rash on the elbows, knees, and scalp—advanced significantly late last year when experts published the Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) in the September 2009 issue of Annals of the Rheumatic Diseases. "This evidence-based guideline categorizes psoriatic arthritis based on the predominant symptoms, and provides a step-wise approach to treatment," says Elaine Husni, MD, MPH, vice chair of the Department of Rheumatology and director of the Arthritis and Musculoskeletal Center at Cleveland Clinic.
The new recommendations should help doctors make more informed choices about treatment for a disease that can vary from very mild psoriasis or ligament inflammation to widespread psoriatic plaques, disfiguring nail disease, and severe joint inflammation that can result in disability and early death.
Joints, skin, nails, and more
Besides a skin rash, psoriatic arthritis also may cause pitting and thickening of the fingernails and toenails, among other symptoms, Dr. Husni says. "Although psoriatic arthritis is often compared with rheumatoid arthritis because both have immune system involvement, the disease course and management are different," she notes. "Psoriatic arthritis falls under a type of arthritis called spondyloarthropathy, and includes five main subtypes." These are:
Peripheral arthritis, a common complication of irritable bowel disease and/or ulcerative colitis. It usually affects the large joints of the arms and legs, including the elbows, wrists, knees, and ankles.
Skin and nail diseases. "The majority of psoriatic arthritis patients develop skin symptoms, and an average of eight to 10 years later, they develop joint symptoms," Dr. Husni explains. "About 10 percent of patients develop joint symptoms first, and then get skin symptoms, and another 10 to 20 percent get skin and joint symptoms at the same time."
Axial disease, a form of psoriatic arthritis that affects the spine. Symptoms include sacroiliitis (inflammation of the pelvic area where the sacrum joins the ilium bone) and spondylitis (inflammation of one or more vertebrae), occurring separately or together.
Enthesitis, inflammation of the ligaments. Symptoms include pain and swelling, often in the heel, fingers, toes, and elbow.
Dactylitis, often referred to as "sausage-shaped" fingers or toes.
Because psoriatic and other kinds of arthritis involve joint pain and/or swelling, if you have these symptoms "it’s important to identify what kind of arthritis you have before attempting therapy," Husni stresses. "What concerns me most is that readers will think that the arthritis advice they see here is applicable to all types of arthritis, and that’s not the case. For example, if you have osteoarthritis, you shouldn’t think you need to be taking the drug methotrexate." However, methotrexate—a disease-modifying disease anti-rheumatic drug (DMARD)—is an appropriate treatment for rheumatoid arthritis and moderate-stage disease in some forms of psoriatic arthritis.
Psoriatic arthritis treatment depends on which symptom is predominant, the severity of the condition, your overall health status, and your medical history. In most cases, especially in the mild stage, the first line of treatment is a nonsteroidal anti-inflammatory drug (NSAID) such as ibuprofen along with lifestyle modifications.
"In that respect, psoriatic arthritis is no different from any other arthritis," Dr. Husni explains. "In the early stage, you need to reduce inflammation and keep moving. Do activities that help you maintain your range of motion—for example, stretching, bending, lifting, and walking—but do not push beyond the point of pain." It’s also important to get down to a normal weight, since excess pounds stress the joints. In that regard, a healthful diet that’s low in fat, high in fiber, and low in sugary foods that can cause spikes in glucose is best, she advises.
After that, depending on the subtype of psoriatic arthritis and its severity, your doctor will probably prescribe a DMARD such as methotrexate (especially if the small joints in the fingers and toes are involved) or a newer class of drugs called TNF (tumor necrosis factor) inhibitors. TNF inhibitors, also known as "biologics," are more likely to be prescribed if you have peripheral arthritis and DMARDs fail to work, or if you have spinal involvement.
Four of the five currently available TNF inhibitors can be used to treat psoriatic arthritis—etanercept (Enbrel), adalimumab (Humira), golimumab (Simponi), and infliximab (Remicade). The fifth inhibitor, certolizumab (Cimzia), is currently in phase III trials to test its effectiveness in psoriatic arthritis.
Which drug to choose can be complicated, especially when it comes to TNF inhibitors. That’s because clinical trials have used different measures of effectiveness, and there have been no head-to-head comparisons of the various drugs available today. Decisions are made after considering such factors as the extent and severity of disease, the drug’s side effects, and any studies that showed effectiveness of the drug in similar patients.
A role for supplements?
"Unfortunately, there is no approved vitamin supplement for psoriatic arthritis," says Dr. Husni. "We’ve found that fish oil has been helpful in patients with rheumatoid arthritis, probably because it has some anti-inflammatory properties that could improve some of the signs and symptoms."
Although no studies have shown that fish oil can help psoriatic arthritis, Dr. Husni says it’s safe to try. "I tell my patients to try it for three months so they don’t waste their money on it for an entire year. If they see an improvement within three months, it’s okay to continue." That said, it’s important to tell your doctor if you’re taking the supplement so he or she can evaluate you accordingly. And, since supplements are not regulated by the U.S. Food and Drug Administration, Dr. Husni advises her patients to purchase all supplements from "larger, more reputable companies."
Although symptoms of psoriatic arthritis may wax and wane, you should continue taking whatever medication has been prescribed for you regardless of whether or not you’re symptomatic. "Right now, we don’t have a cure for psoriatic arthritis or psoriasis, but we can keep the symptoms under control," Dr. Husni emphasizes.
"Many patients believe that when their symptoms are at zero they’re in remission, but we as physicians and rheumatologists know that it’s only because you’re on a prescribed drug. If you’re not taking the drug, your symptoms will return," she cautions.