Association of disease activity using SDAI and DAS28, but not JADAS-27, with subsequent changes in physical function in adult patients with juvenile idiopathic arthritis

Objectives To investigate an optimal composite score for disease activity in adult JIA from the viewpoint of the subsequent changes in physical function. Methods Patients with JIA under the following conditions were enrolled: 1) disease onset < 18 years; 2) registered in the database by Tokyo Women’s Medical University for the first time between 2000 and 2020; and 3) ≥18 years old at the time of registration. Patients were stratified according to mean disease activity scores in SDAI, DAS28, and JADAS-27 during the first year from baseline. Trends of estimated mean change in Japanese-HAQ score (ΔJ-HAQ) from baseline to 2 years later was examined across the stratified groups of each index. Results We included 294 eligible individuals (median age at onset, 14.0 years; RF positive in 64.7%). A significant increasing trend of the estimated mean ΔJ-HAQ at 2 years after baseline was observed along with an increase in the mean disease activity during the first year measured using DAS28 (p = 0.01) and SDAI (p = 0.018), but not using JADAS-27. Conclusions Disease activity measured using SDAI and DAS28, but not using JADAS27, was significantly associated with subsequent changes in physical function in adult patients with JIA.