OBJECTIVES: Severity of psoriasis is a major factor in a physician’s treatment decision. The objective of this research was to evaluate the relationship between the Physician Global Assessment and Body Surface Area product (PGA x BSA) and the Psoriasis Area and Severity Index (PASI) for assessing disease activity in psoriasis patients in specialty dermatology networks in the United States (US).

METHODS: Patients from 6 specialty dermatology networks within the OMNY Health Database with an indication of psoriasis (diagnosis code L40*) and with PASI, PGA, and BSA scores recorded on the same day from 2017 to 2022 were included. Demographic characteristics were tabulated at first score. The Spearman correlation coefficient between PGA x BSA and PASI was generated. Mean PASI score was computed by PGA x BSA quartile, and analysis of variance (ANOVA) was employed to assess the relationship.

RESULTS: From the 254,306 psoriasis patients, 187 patients with 359 observations were included. Distributions of gender (57% male), race (52% white, 38% other, 10% black among known categories), age (35% ≥ 61 years, 61% 21-60 years, 4% ≤ 20 years), and region (52% South, 40% West, 8% Midwest) were tabulated. The Spearman coefficient between PGA x BSA and PASI was 0.83. Mean (standard deviation) PASI scores for PGA x BSA quartiles 1-4 were 1.4 (1.6), 6.9 (3.9), 10.4 (6.3), and 19.4 (13.4), respectively, demonstrating a monotonically positive relationship (ANOVA p < 0.001).

CONCLUSIONS: Administering the PASI tool in the real-world setting is time consuming, and the strong correlation between PGA x BSA and PASI may offer an opportunity to measure psoriasis disease activity more efficiently in routine clinical practice. Additional analyses accounting for patient characteristics and other clinical factors would be beneficial to understand independent contributions of those factors to PASI score.