Association of BMI, BMR, BSA, and body weight with psoriasis severity and treatment response: evidence from a real-world cohort

Abstract

Background: Although biologic and systemic therapies have advanced psoriasis management, real-world evidence guiding individualized treatment remains limited. In particular, the influence of body size and metabolic parameters on disease severity and treatment response is underexplored. Objective: To investigate the associations of body mass index (BMI), basal metabolic rate (BMR), body surface area (BSA), and body weight with baseline psoriasis severity and therapeutic response across different treatment modalities. Methods: This multicenter, prospective study included 1955 patients from the Shanghai Psoriasis Effectiveness Evaluation CoHort (SPEECH) and 1663 patients for longitudinal follow-up. Multivariable regression models were used to examine the associations between body size/metabolic parameters and the baseline psoriasis area and severity index (PASI) scores, as well as PASI-based treatment responses at Week 12 and Week 20. Stratified analyses by treatment type and receiver operating characteristic curve analysis were conducted to assess predictive performance. Results: All four parameters were positively associated with baseline PASI scores (FDR-adjusted P < 0.05). Prospectively, elevated BMI, BMR, BSA, and body weight were significantly associated with reduced likelihood of achieving PASI 75/90/100, and lower percentage reduction in PASI score at both time points. These associations were particularly pronounced in patients receiving biologic therapies. In the ustekinumab subgroup, body composition showed enhanced predictive accuracy for high-level PASI responses. Conclusion: Elevated BMI, BSA, body weight, and BMR are associated with more severe psoriasis and diminished treatment efficacy, especially those treated with biologics. These findings underscore the need for personalized dosing strategies in biologic therapy, especially for fixed-dose agents like ustekinumab.