Modeling Posttreatment Prognosis of Skin Lesions in Patients With Psoriasis in China.

Importance: Understanding the posttreatment prognosis of skin lesions in patients with psoriasis is essential for improving patients' treatment satisfaction. Objectives: To model the prognosis of skin lesions for patients with psoriasis after 3 types of therapy. Design, Setting, and Participants: This prospective cohort study included patients with psoriasis who visited a dermatologist and were enrolled in the platform of the Psoriasis Standardized Diagnosis and Treatment Center in China from August 2020 to December 2021. Interventions: Biologic, traditional, and systemic therapy for psoriasis. Main Outcomes and Measures: Skin lesions were measured by the Investigator's Global Assessment (IGA) scale subsumed into 4 stages of severity (IGA 0/1, IGA 2, IGA 3, and IGA 4), with higher scores indicating higher severity. The matching method was used to balance baseline covariates between patients receiving each of the 3 treatments. Transition probabilities from IGA scores at baseline to 0 to 1 month and 1 to 12 months were estimated. Results: A total of 8767 patients were included in the final analysis (median age, 38.6 years [IQR, 28.7-52.8 years]; 5809 [66.3%] male). Across the 3 therapies, as the follow-up duration increased, the probability of improvement transition into a less severe IGA stage (from IGA 4 to IGA 0/1) increased from 0.19 (95% CI, 0.18-0.21) in 0 to 1 month to 0.36 (95% CI, 0.34-0.37) in 1 to 12 months. Biologic therapy was associated with greater improvement transitions for severe conditions, with transition probabilities from IGA 4 to IGA 0/1 increasing by 0.06 (95% CI, 0.02-0.09) vs traditional therapy and by 0.06 (95% CI, 0.03-0.09) vs systemic therapy in 0 to 1 month and by 0.08 (95% CI, 0.04-0.12) vs traditional therapy and 0.11 (95% CI, 0.07-0.14) vs systemic therapy in 1 to 12 months. Conclusions and Relevance: This cohort study modeling psoriasis prognosis provided a complete prognosis of skin lesions, and biologic therapy was associated with improved prognosis of moderate to severe psoriasis compared with traditional and systemic therapies. The study provides insight on using transition diagrams to assess psoriasis prognosis and to communicate with patients in clinical practice.