Abstract Purpose: This study aims to investigate the prevalence and patterns of type II inflammatory disease among adult patients with psoriasis in China, including the associated comorbidities and coexisting conditions. Patients and methods: Data were collected from the register of China National Clinical Center for Skin and Immune Diseases between June 2020 and May 2023. Univariate and a multivariable logistic regression models were used to analyze the factors associated with type II inflammatory disease in patients with psoriasis. Results: A total of 15172 adults with psoriasis were included in this study, and the mean age was 42.46 years and 35.21% were females. Among them, 725 were identified to have type II inflammatory disease, resulting in an overall prevalence of 4.78%. Multivariate logistic regression analysis suggested that the odds ratio (95% confidence interval) for type II inflammatory disease in patients with psoriasis was 1.12 (1.06-1.18) for older age (per 10-year increase), 1.05 (0.89-1.23) for female sex, 1.03 (0.81-1.32) for obesity (BMI≥28kg/m2), 1.32 (1.10-1.58) for smoking, 17.21 (10.46-28.30) for hypertension, 3.14 (2.47-3.99) for history of drug allergy, 1.56 (1.28-1.19) for family history of psoriasis, and 0.60 (0.49-0.73) for severity of the disease (severe vs mild psoriasis). Conclusion: Our results indicate that type II inflammatory diseases in patients with psoriasis is associated with smoking, hypertension, history of drug allergy, and family history of psoriasis. Furthermore, we observed a correlation between  the severity of psoriasis and a decreased likelihood of type II inflammatory diseases. This study contribute to valuable real-world data with regard to epidemiological features of type II inflammation among patients with psoriasis in China. It also offer insights into potential risk factors for targeted interventions and personalized treatment strategies in clinical setting.

The authors have declared no competing interest.

The author(s) received no specific funding for this work.

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This study was approved by the Ethical Committee of the register of China National Clinical Center for Skin and Immune Diseases (2020-255) and Jining No.1 People's Hospital (2021-084). The electronic informed consent form was obtained from all the patients in the study.

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