Validation of the revised definition of lupus low disease activity in patients with SLE

OBJECTIVE: EULAR recently updated its recommendation for managing SLE by redefining the lupus low disease activity state (LLDAS) with a reduced allowable glucocorticoid dose of ≤5 mg. No studies have validated this revised definition. Thus, we aimed to evaluate its association with clinical outcomes, including organ damage, disease flares and quality of life. METHODS: A total of 299 SLE patients were enrolled and conducted annual follow-ups over 4 years. Disease flares were assessed based on changes from previous visits. Disease activity was measured using the SLE Disease Activity Index 2000 (SLEDAI-2K) and the Physician Global Assessment (PGA). Irreversible organ damage was evaluated using the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI). Quality of life was assessed using the SF-36, with a focus on the Physical and Mental Component Summary (PCS and MCS) scores. Longitudinal analyses were performed using generalized estimating equations models to compare the revised and existing LLDAS definitions. RESULTS: The revised LLDAS definition was significantly associated with reduced organ damage (SLICC/ACR SDI, β = -2.922; 95% CI: -3.294 to -2.550; P < 0.001), lower disease flare risk (odds ratio = 0.207; 95% CI: 0.083-0.515; P < 0.001) and improved mental health (SF-36 MCS, β = 1.219; 95% CI: 0.114-2.323; P = 0.031), showing comparable effectiveness to the existing definition. CONCLUSION: The revised LLDAS definition demonstrated comparable clinical benefits, supporting its adoption in clinical practice for improved long-term SLE management.