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Objectives Systemic lupus erythematosus (SLE) disease activity leads to irreversible organ damage, if not managed adequately. Compared to SLE Disease Activity Index 2000 (SLEDAI-2K) the recently developed SLE Disease Activity Score (SLE-DAS) has shown higher sensitivity to change (Jesus, Ann Rheum Dis. 2019;78(3):365-371). We aimed to determine the ability of SLE-DAS and SLEDAI-2K to predict organ damage accrual assessed with the SLICC/ACR Damage Index (SDI) in a Swedish real-world SLE cohort.Methods Patients fulfilling the 2012 SLICC classification criteria for SLE followed at a Swedish referral centre (Clinical Lupus Register in North-eastern Gothia - KLURING) with at least 2 outpatient visits from 2008 to 2025 were included. SLEDAI-2K and clinical (c)SLEDAI-2K were scored prospectively at each visit, and the SDI was assessed annually. SLE-DAS was scored retrospectively for each visit. The adjusted mean score of SLEDAI-2K (amSLEDAI), cSLEDAI-2K (amcSLEDAI), and SLE-DAS (amSLE-DAS) were determined for each patient and each time interval between consecutive visits. The ability of amSLEDAI, amcSLEDAI, and amSLE-DAS to predict damage accrual (SDI increase from baseline) was evaluated in a time-dependent manner, applying multivariable Cox regression models, along with age and sex as covariates fixed at baseline and prednisone-equivalent dose as a time-dependent variable. Models were applied for 3, 5, and 7 years of follow-up. The predictive value of amSLE-DAS, amcSLEDAI, and amSLEDAI were compared using Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC).Results In total, 335 patients contributed to the analysis (86% women, 23% with history of or current lupus nephritis, 66% with SDI>0 at baseline), totalling 3582 visits. Results are detailed in table 1; amSLE-DAS was an independent predictor of SDI increase at the 3-, 5-, and 7-year follow-up while amSLEDAI was predictive at the 5-year follow-up only. amSLE-DAS showed a higher predictive value for organ damage accrual than amSLEDAI and amcSLEDAI at 3, 5, and 7 years of follow-up, indicated by lower values of AIC and BIC.Abstract S7:05 Table 1Multivariate cox regression analysis for damage accrualConclusions Data from KLURING illustrate that assessment of SLE-DAS is clinically meaningful and yields higher performance in predicting damage accrual compared with SLEDAI-2K and cSLEDAI-2K. Larger studies are warranted to further evaluate SLE-DAS as a disease activity measure.