Validation of the Systemic Lupus Erythematosus Disease Activity Score (SLE-DAS) in a Chinese Cohort: Comparison with SLEDAI-2-K
摘要
Accurate assessment of disease activity in systemic lupus erythematosus (SLE) remains a persistent challenge. We aimed to validate the SLE disease activity score (SLE-DAS) in Chinese patients.
MethodsWe analyzed the agreement between SLE-DAS and SLEDAI-2 K using our prospective STAR cohort. Construct validity was assessed through correlations with physician global assessment (PGA), as well as through known-group discrimination (PGA-cut off ≥ 1 for active). Factors associated with classification discordance and the association between baseline SLE-DAS and 12-month organ damage accrual were assessed using logistic regression.
ResultsAmong 507 SLE patients, SLE-DAS demonstrated strong correlations with PGA (r = 0.726, P < 0.001) and SLEDAI-2 K (r = 0.750, P < 0.001), with an overall agreement of 83.0% between SLE-DAS and SLEDAI-2 K. Both instruments demonstrated comparable discriminative power for active disease (SLE-DAS AUC = 0.832; SLEDAI-2 K AUC = 0.860). Among 211 patients with mild disease activity classified by SLEDAI-2 K, 61 were reclassified into higher categories by SLE-DAS. These patients exhibited higher PGA (0.8 ± 1.0 vs. 0.3 ± 0.7; P < 0.001) and glucocorticoid doses (25.7 ± 22.3 vs. 11.3 ± 15.5; P < 0.001) than those with concordant classifications. Lupus nephritis (45.9% vs. 18.0%; P < 0.001) and hematological involvement (32.8% vs. 18.0%; P = 0.020) were more frequent in them. We identified that nephritis (OR = 4.57, 95% CI 2.18–9.57, P < 0.001) and hematological involvement (OR = 2.76, 95% CI 1.27–6.02, P = 0.011) were associated with classification discordance. Baseline SLE-DAS was positively associated with SLE SLICC/ACR Damage Index (SDI) accrual at 12 months of follow-up (OR = 1.38, P = 0.038).
ConclusionsSLE-DAS demonstrates superior accuracy in assessing disease activity compared to SLEDAI-2 K, likely attributable to refinements in assessing nephritis and hematological manifestations. Baseline SLE-DAS also exhibited a positive association with short-term organ damage accrual, though long-term validation is required.