Ability of SLE-DAS and SLEDAI-2K to predict damage accrual in SLE: a real-world 7-year cohort study from Sweden.

Abstract

Objectives: SLE remains a heterogeneous autoimmune disease that can lead to irreversible organ damage. SLE Disease Activity Score (SLE-DAS) is a recently developed tool with higher sensitivity to change than SLE Disease Activity Index-2000 (SLEDAI-2K). We compared SLE-DAS with other activity measures in terms of ability to predict organ damage.

Methods: Patients from Linköping University Hospital with ≥2 visits between 2008 and 2025 were included. SLEDAI-2K and Physician's Global Assessment (PhGA) were assessed prospectively, and SLE-DAS retrospectively. Organ damage was estimated annually using the SLICC/ACR Damage Index (SDI). Adjusted mean scores of SLEDAI-2K (amSLEDAI-2K), PhGA (amPhGA) and SLE-DAS (amSLE-DAS) were determined for each time interval between consecutive visits, and their ability to predict damage accrual was evaluated using time-dependent multivariable Cox regression models. Predictive ability was compared across measures using Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC).

Results: In total, 335 patients with 3582 outpatient visits contributed data. amSLE-DAS was an independent predictor of SDI increase at the 3- (HR; 95% CI: 1.04; 1.00-1.08), 5- (1.05; 1.01-1.09) and 7-year follow-up (1.04; 1.00-1.08). amSLEDAI-2K was predictive at the 5-year follow-up only (1.12; 1.02-1.22), and amPhGA at 5 (1.99; 1.19-3.36) and 7 (1.84; 1.02-3.30) years. amSLE-DAS showed a higher predictive ability for damage accrual than amSLEDAI-2K at the 3-, 5- and 7-year follow-up, as indicated by lower AIC and BIC.

Conclusion: In this real-world Swedish setting, we demonstrate that SLE-DAS outperforms SLEDAI-2K in predicting organ damage accrual in SLE, substantiating its clinical relevance.