Focusing on patients with psoriasis
Treatment of psoriasis makes sense to address several quality-of-life issues, but controlling the severity of psoriatic skin manifestations gives patients no guarantees about their possible progression to PsA.
Dr. Laura C. Coates
“So many people have mild psoriasis that, although they are less likely, proportionately, to get PsA, we still see many in the clinic,” said Dr. Coates. “Patients with severe skin involvement have a good reason to get treatment, which could help test whether a drug slows progression to arthritis. But it’s unethical to not treat severe psoriasis just to have a comparison group.” Aside from skin psoriasis, “we don’t have any other good markers,” Dr. Coates noted.
PsA can develop in patients who had psoriasis in the past but without currently active disease. “At the level of individual patients you can’t say someone is protected from developing PsA because their psoriasis is inactive,” Dr. Eder said. “No study has looked at whether treatment of psoriasis reduces the risk for progression to PsA. We don’t know whether any treatments that reduce inflammation in psoriasis also reduce progression to PsA.” Regardless, treating psoriasis is important because it improves quality of life and may have a beneficial, long-term effects on possible cardiovascular disease effects from psoriasis, Dr. Eder said.
Dr. Soumya Reddy
Her research group is now studying the associations among different biological drugs taken by patients with psoriasis and their subsequent incidence of PsA with use of medical records from about 4 million Israeli residents. Other studies are also looking at this, but they are all observational and therefore are subject to unidentified confounders, she noted. A more definitive demonstration of PsA protection would need a randomized trial.
“The idea of preventing the transition from psoriasis to PsA is an exciting concept. But currently, there are no established treatments for preventing transition of psoriasis to PsA. It’s an area of active research, and the holy grail of psoriatic disease research. We do not yet know whether successful treatment of skin psoriasis delays the onset of arthritis,” Dr. Reddy said in an interview.
Dr. Joel M. Gelfand
“The risk of developing PsA increases as the severity of skin psoriasis increases, measured by percentage of body surface area affected. However, there is only a weak correlation between the severity of skin disease and the severity of PsA,” said Joel M. Gelfand, MD, professor of dermatology at the University of Pennsylvania in Philadelphia.