Defining Low Disease Activity in Systemic Lupus Erythematosus

Area of Science:

• Rheumatology
• Clinical Immunology
• Systemic Lupus Erythematosus Research

Background:

• Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with variable disease activity.
• Defining low disease activity (LDA) is crucial for assessing patient outcomes and guiding treatment strategies.
• Previous studies have focused on remission and high disease activity (HDA), with less emphasis on the specific characteristics and outcomes of LDA.

Purpose of the Study:

• To establish clear criteria for identifying patients with SLE experiencing low disease activity (LDA).
• To compare the short-term outcomes of LDA patients with those in remission and those with high disease activity (HDA).
• To evaluate the potential utility of LDA as an endpoint in clinical trials and treatment regimens.

Main Methods:

• Defined LDA using the SLEDAI-2K score (<3) and specific clinical manifestations, allowing for antimalarial use.
• Defined remission as no clinical manifestations with antimalarial monotherapy and HDA as SLEDAI-2K >6.
• Included patients with at least 1 year of follow-up data.

Main Results:

• Identified 80 patients (12.9%) with LDA, 191 (30.8%) in remission, and 349 (56.3%) with HDA from 620 SLE patients.
• LDA and remission groups demonstrated similar short-term outcomes, including SLEDAI-2K scores, organ involvement, and mortality.
• HDA patients exhibited significantly worse outcomes, with higher SLEDAI-2K scores, major organ involvement, mortality, and therapy needs compared to LDA/remission groups.

Conclusions:

• Low disease activity (LDA) and remission in SLE patients yield comparable short-term outcomes.
• Both LDA and remission represent a better prognosis than high disease activity (HDA).
• LDA can be effectively utilized as an outcome measure in therapeutic trials and treat-to-target strategies for SLE.