in patients, compared with those on topical therapy, a new study finds.
“Our study results suggest that psoriasis is an independent risk factor for COVID-19 illness,” study coauthor Jeffrey Liu, a medical student at the University of Southern California, Los Angeles, said in an interview after he presented the findings at the American Academy of Dermatology Virtual Meeting Experience. “And our findings are consistent with the hypothesis that certain systemic agents may confer a protective effect against COVID-19 illness.”
Mr. Liu and coinvestigators used a Symphony Health dataset to analyze the health records of 167,027 U.S. patients diagnosed with psoriasis and a control group of 1,002,162 patients. The participants, all at least 20 years old, had been treated for psoriasis or psoriatic arthritis from May 2019 through Jan. 1, 2020, and were tracked until Nov. 11, 2020.
The ages and races of peoples in the two groups were roughly similar. Overall, 55% were women and 75% were White, and their average age was 58 years. Type 2 diabetes was more common in the psoriasis group than the control group (23% vs. 16%), as was obesity (27% vs. 15%). Of the patients with psoriasis, 60% were on topical treatments, 19% were on oral therapies, and 22% were on biologic therapy, with only a few taking both oral and biologic therapies.
After adjustment for age and gender, patients with psoriasis were 33% more likely than the control group to develop COVID-19 (adjusted incidence rate ratio, 1.33; 95% confidence interval, 1.23-1.38; P < .0001).
In a separate analysis, the gap persisted after adjustment for demographics and comorbidities: Patients with psoriasis had a higher rate of COVID-19 infection vs. controls (adjusted odds ratio, 1.18; 95% CI, 1.13-1.23; P < .0001). Among all patients, non-White race, older age, and comorbidities were all linked to higher risk of COVID-19 (all P < .0001).
Psoriasis might make patients more vulnerable to COVID-19 because the presence of up-regulated genes in psoriatic skin “may lead to systemic hyperinflammation and sensitization of patients with psoriasis to proinflammatory cytokine storm,” Mr. Liu said. This, in turn, may trigger more severe symptomatic disease that requires medical treatment, he said.
Reduced risk, compared with topical therapies
After adjustment for age and gender, those treated with TNF-alpha inhibitors, methotrexate, and apremilast (Otezla) all had statistically lower risks of COVID-19 vs. those on topical therapy (aIRR, 0.82; 95% CI, 0.69-0.95; P < .0029 for TNF-alpha inhibitors; aIRR, 0.75; 95% CI, 0.67-0.86; P < .0001 for methotrexate; and aIRR, 0.69; 95% CI, 0.55-0.85; P < .0006 for apremilast).
Reduced risk held true for those in the separate analysis after adjustment for comorbidities and demographics (respectively, aOR, 0.87; 95% CI, 0.77-1.00; P < .0469; aOR, 0.81; 95% CI, 0.71-0.92; P < .0011; and aOR, 0.70; 95% CI, 0.57-0.87; P < .0014).
Apremilast and methotrexate may boost protection against COVID-19 by inhibiting the body’s production of cytokines, Mr. Liu said.
One message of the study is that “dermatologists should not be scared of prescribing biologics or oral therapies for psoriasis,” the study’s lead author Jashin J. Wu, MD, of the Dermatology Research and Education Foundation in Irvine, Calif., said in an interview.
However, the results on the effects of systemic therapies were not all positive. Interleukin (IL)–17 inhibitors were an outlier: After adjustment for age and gender, patients treated with this class of drugs were 36% more likely to develop COVID-19 than those on oral agents (aIRR, 1.36; 95% CI, 1.13-1.63; P < .0009).
Among patients on biologics, those taking IL-17 inhibitors had the highest risk of COVID-19, Mr. Liu said. “The risk was higher in this class regardless of reference group – general population, the topical cohort, and the oral cohort,” he said. “This may relate to the observation that this biologic class exerts more broad immunosuppressive effects on antiviral host immunity. Notably, large meta-estimates of pivotal trials have observed increased risk of respiratory tract infections for patients on IL-17 inhibitors.”
In an interview, Erica Dommasch, MD, MPH, of the department of dermatology at Beth Israel Deaconess Medical Center, Boston, cautioned that “the data from this study is very hard to interpret.”
It’s likely that some patients with psoriasis on systemic medications “may have been the most careful about limiting exposures,” she said. “Thus, it’s hard to account for behavioral changes in individuals that may have led to the decreased incidence in psoriasis in patients on systemic agents versus topical therapy alone.”
Patients with psoriasis may also be tested more often for COVID-19, and unmeasured comorbidities like chronic kidney disease may play a role too, she said. Still, she added, “it’s reassuring that the authors did not find an increased rate of COVID among psoriasis patients on systemic agents versus topicals alone.” And she agreed with Dr. Wu about the importance of treating psoriasis with therapy beyond topical treatments during the pandemic: “Providers should feel comfortable prescribing systemic medications to psoriasis patients when otherwise appropriate.”
As for the next steps, Dr. Wu said, “we will be exploring more about the prognosis of COVID-19 infection in psoriasis patients. In addition, we will be exploring the relationship of COVID-19 infection with other inflammatory skin diseases, such as atopic dermatitis.”
No study funding is reported. Dr. Wu discloses investigator, consultant, or speaker relationships with AbbVie, Almirall, Amgen, Arcutis, Aristea Therapeutics, Boehringer Ingelheim, Bristol-Myers Squibb, Dermavant, Dr. Reddy’s Laboratories, Eli Lilly, Galderma, Janssen, LEO Pharma, Mindera, Novartis, Regeneron, Sanofi Genzyme, Solius, Sun Pharmaceutical, UCB, Valeant Pharmaceuticals North America, and Zerigo Health. Mr. Liu and Dr. Dommasch have no disclosures.