ANALYSIS OF ACTIVITY AND REMISSION INDICES IN SYSTEMIC LUPUS ERYTHEMATOSUS: COMPARISON BETWEEN SLEDAI-2K AND SLE-DAS, AND ASSOCIATION WITH LLDAS AND DORIS2021

Background: Activity indices in Systemic Lupus Erythematosus (SLE) are tools to assess disease severity, guide treatment decisions, and evaluate treatment response. The commonly used SLEDAI-2K has been recently joined by SLE-DAS. “Treat to target” strategies have gained importance, aiming for remission or low disease activity, defining Lupus Low Disease Activity State (LLDAS) and DORIS2021 remission. Objectives: To assess the relationship between SLEDAI-2K and SLE-DAS and the definition of low disease activity (LLDAS) and remission (DORIS2021) in SLE. Methods: A retrospective descriptive cross-sectional study was conducted in a cohort of patients diagnosed with SLE, visited between September 2022 and November 2023 at a tertiary hospital. Patients had to meet EULAR/ACR 2019 Classification Criteria at some point during their disease course. Demographic, clinical, analytical, and index variables were collected. Analysis of variables was performed using Spearman’s correlation coefficient and Mann-Whitney U test. Statistical significance was set at p<0.05. Results: A total of 57 patients were included (94.7% females, mean age 48.5 years, mean disease duration 13.08 years). Common manifestations included arthralgia (35.1%) and arthritis (12.3%). Less frequent were cutaneous involvement (7%) and oral mucosal ulcerations (3.5%). No cases of serositis, fever, or myositis were observed. Urinary sediment abnormalities were present in 28.1% of patients, and 7% had significant proteinuria. Only 1 patient experienced a renal flare. Serologically, 36.8% had elevated DNA levels, and 36.8% had low C3 and/or C4 levels. Table 1 displays values and relationships between SLEDAI-2K and SLE-DAS by activity. No patients had severe SLEDAI-2K (>10). The correlation between the two indices was good (Spearman’s coefficient 0.786, p<0.001). However, when variables were categorized (remission, mild, moderate, severe), the relationship disappeared (kappa coefficient 0.186, p=0.064). In our cohort, 71.9% of patients were in remission according to SLE-DAS, and 35.1% according to SLEDAI-2K. Additionally, 78.9% and 68.4% of patients met LLDAS and DORIS2021 criteria, respectively. Table 2 shows relationships between each activity index and LLDAS and DORIS2021. Both SLEDAI-2K and SLE-DAS were significantly associated with LLDAS (p=0.006 and p<0.001, respectively) and DORIS2021 (p=0.018 and p<0.001, respectively). Table 1. SLE-DAS remission (≤2.8) n (%) SLE-DAS mild (2,09-7.64) n (%) SLE-DAS moderate/severe (≥7.65) n (%) Total n (%) SLEDAI2K remission (=0) n (%) 19 (33.3) 1 (1.8) 0 20 (35.1) SLEDAI2K mild (1-5) n (%) 22 (38.6) 7 (12.3) 3 (5.3) 32 (56.1) SLEDAI2K moderate (6-10) n (%) 0 4 (7) 1 (1.8) 5 (8.8) Total n (%) 41 (71.9) 12 (21.2) 4 (7) 57 (100) Table 2. Median SLEDAI-2K SLEDAI-2K remission n (%) SLEDAI-2K mild n (%) SLEDAI-2K moderate n (%) LLDAS not met 3.83 1 (1.8) 6 (10.5) 5 (8.8) LLDAS met 1.69 19 (33.3) 26 (45.6) 0 DORIS2021 not met 3.22 3 (5.3) 10 (17.5) 5 (8.8) DORIS2021 met 1.64 17 (29.8) 22 (38.6) 0 Median SLE-DAS SLE-DAS remission n (%) SLE-DAS mild n (%) SLE-DAS moderate/severe n (%) LLDAS not met 5.25 2 (3.5) 8 (14) 2 (3.5) LLDAS met 1.66 39 (68.4) 4 (7) 2 (3.5) DORIS2021 not met 4.40 5 (8.8) 11 (19.3) 2 (3.5) DORIS2021 met 1.5 36 (63.2) 1 (1.8) 2 (3.5) Conclusion: A significant correlation exists between SLEDAI-2K and SLE-DAS, but it loses significance when variables are categorized. This is attributed to substantial divergence in remission and low activity categories between the two indices. With the exception of one patient (1.8%) in SLEDAI-2K remission, all others meet remission criteria by SLE-DAS. However, many patients in SLE-DAS remission exhibit mild activity in SLEDAI-2K, mainly due to serological manifestations. Both indices show a significant association with LLDAS and DORIS2021, despite SLE-DAS not being part of their definitions. Notably, the proportion of patients in remission by SLE-DAS aligns more closely with the proportions of LLDAS and DORIS2021 than SLEDAI-2K. REFERENCES: NIL. Acknowledgements: NIL. Disclosure of Interests: None declared. DOI: 10.1136/annrheumdis-2024-eular.4255 Keywords: Observational studies/ registry, Remission Citation: , volume 83, supplement 1, year 2024, page 1876Session: Systemic lupus erythematosus (Publication Only)

Observational studies/ registry, Remission