It’s high time to say farewell to the traditional categorization of psoriasis severity into mild, moderate, or severe disease, according to the International Psoriasis Council.

Dr. Bruce E. Strober

The mild/moderate/severe categorization is vague and defined differently by different organizations and in different countries. It often underestimates disease severity because it ignores psoriasis involvement in particularly tough-to-treat special areas, including the scalp, palms, soles, face, nails, and genitalia, Bruce E. Strober, MD, PhD, asserted at MedscapeLive’s annual Las Vegas Dermatology Seminar, held virtually this year. He chaired an IPC project in which prominent psoriasis experts in 32 countries employed a Delphi consensus approach aimed at achieving agreement on a more practical recategorization of psoriasis severity for use in both daily clinical practice and enrolling appropriate participants in clinical trials. What emerged was a simplified dichotomous categorization system.

“What we came up with is a very sensible approach to defining whether patients should get either topical or systemic therapy. In fact, there are only two groups of patients in psoriasis: those who should get topicals alone, and those who should get systemic therapy. It’s topicals or systemics,” explained Dr. Strober, a dermatologist at Yale University, New Haven, Conn., who also works in private practice in Cromwell, Conn.

Under the IPC classification, psoriasis patients are candidates for systemic therapy if they meet at least one of three criteria: body surface area of involvement greater than 10%, disease involving the previously mentioned special areas, or failure of topical therapy.

“This approach is about practically treating patients who are in need,” Dr. Strober said. “If patients meet just one of these three criteria they can move on to our current toolbox of systemic therapies, be they older systemic treatments, apremilast, phototherapy, or 1 of the 11 biologics currently approved for the treatment of psoriasis. The key point is that for patients with moderate to severe psoriasis – or should I say, systemic therapy–appropriate psoriasis – treatment should be based on individual patient characteristics. We don’t work on a stepwise approach. If a patient walks in with more than 10% body surface area involved, don’t make them fail topicals; you can go right to systemics.”

European dermatologists often use the Psoriasis Area and Severity Index (PASI) score to characterize disease severity and monitor response to therapy. In contrast, American dermatologists generally find PASI too complex and time-consuming for use in clinical practice, relying instead on the amount of body surface area involved with psoriasis. Neither of these measures incorporates disease involvement in special areas, which when present ought to automatically place a patient in the systemic therapy–appropriate category, according to Dr. Strober.

“I find this [IPC recategorization] a very practical approach. I hope you write this down and use this in your own practice,” Dr. Strober said.

The full IPC report was published in the Journal of the American Academy of Dermatology.

The IPC psoriasis severity reclassification project was unfunded. Dr. Strober reported receiving institutional research funding from and serving as a paid consultant to more than two dozen pharmaceutical companies.

MedscapeLive and this news organization are owned by the same parent company.

bjancin@mdedge.com