Predictors of improvement in disease activity in first hospitalized patients with systemic lupus erythematosus: a multicenter retrospective study of a Chinese cohort

OBJECTIVES: To analyze the relative factors of improvement in disease activity (IDA) after first hospitalized treatment based on the systemic lupus erythematosus disease activity index (SLEDAI). METHODS: A total of 1069 adult systemic lupus erythematosus (SLE) patients who were hospitalized for the first time in 26 hospitals in Jiangsu Province from 1999 to 2009 were retrospectively analyzed. SLEDAI decrease ≥ 4 during hospitalization was identified as IDA. Relative factors of IDA were assessed by univariate and multivariate logistic regression. RESULTS: A total of 783 (73.2%) adult SLE patients showed IDA after the first hospitalization, while the remaining patients (n = 286) were in the non-IDA group. The IDA group had higher SLEDAI at admission; fewer patients had SLICC/ACR damage index (SDI) ≥ 1, comorbidities at admission, especially Sjögren’s syndrome, abnormal serum creatinine, and glomerular filtration rate. More patients had mucocutaneous and musculoskeletal involvements, leukopenia, increased C-reactive protein, anti-dsDNA antibody positive, and hypocomplementemia at admission and were treated with methotrexate and leflunomide during hospitalization. After multivariate logistic regression analysis, SDI ≥ 1 (P = 0.005) and combined with Sjögren’s syndrome (P < 0.001) at admission had negative association with IDA. Musculoskeletal involvement (P < 0.001), anti-dsDNA antibody positive (P = 0.012), hypocomplementemia (P = 0.001), and use of leflunomide (P = 0.030) were significantly related with IDA. CONCLUSION: Organ damage or comorbidities at admission were adverse to SLE improvement. Anti-dsDNA antibody positive, hypocomplementemia, musculoskeletal involvements, and leflunomide treatment had positive association with IDA of SLE.