Baseline demographic and clinical characteristics (n=759)
| Age (years) | 39.8 (12.0) |
| Female, n (%) | 714 (94) |
| Race, n (%) | |
| American Indian or Alaska Native | 97 (13) |
| Asian | 115 (15) |
| Black or African American | 86 (11) |
| Multiple | 8 (1) |
| White | 453 (60) |
| Immunosuppressants, n (%) | |
| Azathioprine | 139 (18) |
| Mycophenolate mofetil | 60 (8) |
| Methotrexate | 80 (11) |
| SLEDAI | 10.3 (3.6) |
| Disease duration (years) | 7.0 (7.0) |
| BILAG | |
| Organ system has an A or B at baseline, n (%) | |
| Constitutional | 16 (2) |
| Mucocutaneous | 520 (69) |
| Musculoskeletal | 471 (62) |
| Cardiorespiratory | 54 (7.1) |
| Neuropsychiatric | 9 (1) |
| Gastrointestinal | 12 (2) |
| Renal | |
| Ophthalmic | 7 (1) |
| Haematological | 1 (0.1) |
| PGA | 45.9 (16.3) |
| White cells (×109/L) | 5.9 (2.4) |
| Lymphocytes (×109/L) | 1.3 (0.7) |
| Neutrophils (×109/L) | 4.1 (2.1) |
| CD19 (%) | 12.8 (8.1) |
| Haemoglobin (g/dL) | 12.4 (1.4) |
| C3 (g/L) | 0.99 (0.31) |
| C4 (g/L) | 0.17 (0.10) |
| Anti-dsDNA (IU/mL) | 110.3 (114.7) |
| Anti-dsDNA ≥30 IU/mL, n (%) | 451 (59.6%) |
| IgG (g/L) | 15.2 (5.2) |
| IgM (g/L) | 1.2 (0.8) |
| IgA (g/L) | 3.1 (1.6) |
| Anti-Sm (U/mL) | 20.3 (34.5) |
| Anti-RNP (U/mL) | 42.3 (53.5) |
| Anti-SSA/Ro (U/mL) | 55.3 (62.3) |
| Anti-SSB/La (U/mL) | 20.2 (36.6) |
| Protein/creatinine>500 mg/g, n (%) | 60 (7.9) |
Except where indicated, values are the mean±SD.
BILAG, British Isles Lupus Assessment Group; PGA, phosphoglyceric acid; SLEDAI, SLE Disease Activity Index.