Predictive factors of atopic‐like dermatitis induced by IL‐17A inhibitors in patients with psoriasis: A 2‐year follow‐up study

Background Atopic‐like dermatitis (ALD) is a common side effect of interleukin‐17A (IL‐17A) inhibitors. Objective To determine the prevalence, risk factors, outcomes and treatment of ALD in a cohort of psoriasis patients treated with IL‐17A inhibitors. Methods This retrospective study included 226 psoriasis patients treated with an IL‐17A inhibitor in our dermatology department between July 2020 and July 2022. The patients were reviewed over 2 years. A logistic regression model in rare events data (relogit) was used to predict the risk factors for ALD. Results Of the 226 patients, 14 had ALD. Data including age, body mass index, IL‐17A inhibitor use, personal and family history of atopic disease, pet ownership history, and immunoglobulin E (IgE) levels were analysed using the relogit regression model. It indicated a personal history of atopic disease (odd ratio [OR] 27.830, 95% confidence interval [CI] 3.801–203.770; p = 0.001) and elevated IgE levels (OR 5.867, 95% CI 1.131–30.434; p = 0.035) as independent predictors of incident ALD. In one patient, anti‐IL‐17A therapy was discontinued, and treatment was switched to tofacitinib. Thirteen patients who continued with IL‐17A inhibitor were treated with topical therapy and/or antihistamines, and their ALD was partially or completely resolved. Conclusion In this study, the incidence rate of ALD was 6.19%. Elevated IgE levels and a personal history of atopic disease were found to be the risk factors for ALD. Our study findings suggest that treatment should be provided based on the severity of psoriasis and incident ALD. Prior to treatment, psoriasis patients who have the risk factors for ALD should be informed of the possible development of ALD, and alternative psoriatic therapeutic options should be considered if severe ALD develops.