• A new study has found that treating psoriasis with biologics may reduce the risk for developing psoriatic arthritis.
• The study followed 1,719 participants who were treated with topicals, conventional disease-modifying antirheumatic drugs (DMARDs), or biologic DMARDs for several years.
• The researchers concluded that biologic DMARDs may lower the risk of developing psoriatic arthritis compared to the other treatments, but more studies are needed.

A new study has found that treating a person’s psoriasis with biologics can lower their chances of developing psoriatic arthritis compared to other treatments. Compared to topicals, conventional DMARDs may also be more effective in reducing a person’s risk of psoriatic arthritis, according to the findings.

Researchers from the Hospital Italiano de Buenos Aires in Buenos Aires, Argentina looked at the effects of using disease-modifying antirheumatic drugs for treating and preventing psoriasis and psoriatic arthritis.

Psoriasis is an inflammatory skin disease that causes dry patches and scales known as plaques to form on the skin. The disease affects more than 7.5 million adults in the United States alone. Psoriatic arthritis results from an abnormal immune response that causes inflammation in a person’s joints as well as an overproduction of skin cells.

There are several treatments for psoriasis, including topical treatments, light therapy, and biologics. Biologics are human-made proteins that help dampen the immune system in inflammatory diseases. These drugs also help slow the progression of the disease.

DMARDs can be classified in two groups, conventional DMARDs and biologic DMARDs. Conventional DMARDs are chemotherapy drugs, such as methotrexate and leflunomide. Biologic DMARDs block specific mediators of inflammation, such as tumor necrosis factor (TNF) alpha, interleukin 17 (IL-17), and IL-12/23.

The researchers were interested in studying the effects of biologics, along with other psoriasis treatments, to see if they prevent psoriatic arthritis. The study followed 1,719 participants, 1,387 (81 percent) of whom were treated with topicals, 229 (13 percent) with conventional DMARDS, and 103 (6 percent) with biologic DMARDs. Researchers followed up with participants at a median time of 7.3 years after the study began to determine which ones had developed psoriatic arthritis.

At the follow-up, researchers found that a total of 239 participants developed psoriatic arthritis. Of them, 231 had been using topicals, whereas only six participants had used conventional DMARDs and two had used biologic DMARDs. The study also found that people who developed psoriatic arthritis had their psoriasis earlier than others, had a higher body mass index (BMI), and were more often male.

With these results, the authors concluded that biologic DMARDs may be more effective for preventing psoriatic arthritis than other kinds of psoriasis treatments. However, more research is necessary, as the authors noted that other studies had found conflicting results.