Abstract Objective To validate the revised patient global assessment (PtGA) threshold of 2 cm in the Boolean 2.0 remission definition by assessing its agreement with index-based remission criteria and its predictive validity for quality of life (QoL) outcomes, compared with Boolean 1.0, in Korean patients with rheumatoid arthritis (RA) receiving targeted therapy. Methods Data from a multicentre prospective cohort of patients with RA initiating treatment with Janus kinase inhibitors or biologic disease-modifying anti-rheumatic drugs were analysed. Remission was assessed using Boolean 1.0, Boolean 2.0, and index-based criteria including Disease Activity Score in 28 joints calculated with erythrocyte sedimentation rate (DAS28-ESR), Clinical Disease Activity Index (CDAI), and Simplified Disease Activity Index (SDAI). Agreement between Boolean definitions and index-based criteria was evaluated using Cohen’s kappa. Predictive validity was determined by comparing remission status at week 24 and patient-reported outcomes at week 48, specifically Health Assessment Questionnaire-Disability Index (HAQ-DI) ≤0.5 and EuroQoL- 5 Dimension (EQ-5D)=1. Results Among 506 enrolled patients, 414 completed the 48-week follow-up. Boolean 2.0 showed stronger agreement with DAS28-ESR remission than Boolean 1.0 (κ = 0.50 vs 0.39), but weaker agreement with CDAI (κ = 0.75 vs 0.48) and SDAI (κ = 0.76 vs 0.64). Boolean 1.0 demonstrated higher positive predictive values for HAQ-DI ≤0.5 (0.90 vs 0.82) and EQ-5D = 1 (0.38 vs 0.30) compared with Boolean 2.0. Conclusion Although Boolean 2.0 improves concordance with DAS28-ESR, it does not enhance the prediction of long-term functional or QoL outcomes. Its broader definition of remission warrants cautious interpretation in clinical practice.
Cho et al. (Tue,) studied this question.