Characteristics of patients with or without damage increase during the 7-year follow-up
| Patients with no increase in SDI during follow-up (142) | Patients with increase in SDI during follow-up (151) | p | |
| Gender (female), n (%) | 123 (86.6) | 130 (86.1) | n.s. |
| Age at recruitment, mean±SD years | 37.3±13.41 | 40.8±12.2 | n.s. |
| SLE duration at recruitment, mean±SD years | 10.7±7.0 | 13.48±8.34 | 0.013 |
| Low C3 or C4 serum levels, n (%) | 126 (89.4) | 131 (86.8) | n.s. |
| Anti-dsDNA Ab, n (%) | 121 (85.2) | 125 (82.8) | n.s. |
| ANA, n (%) | 142 (100) | 151 (100) | n.s. |
| Antiphospholipid Ab, n (%) | 33 (23.2) | 63 (41.7) | 0.001 |
| SDI in 2008, mean±SD | 0.42±0.84 | 0.85±1.16 | 0.007 |
| Lupus manifestations at baseline | |||
| SLEDAI-2K, mean±SD | 3.90±3.76 | 4.98±4.59 | 0.032 |
| PGA >1, n (%) | 32 (23.5) | 39 (26.9) | n.s. |
| Skin rashes, n (%) | 12 (9.8) | 35 (23.2) | <0.001 |
| Arthritis, n (%) | 13 (9.2) | 17 (11.3) | n.s. |
| Serositis, n (%) | 1 (0.7) | 3 (2.0) | n.s. |
| Glomerulonephritis, n (%) | 32 (22.5) | 27 (17.9) | n.s. |
| NP manifestations, n (%) | 1 (0.7) | 1 (0.7) | n.s. |
| Vasculitis, n (%) | 2 (1.4) | 8 (5.3) | n.s. |
| Haematological involvement, n (%) | 10 (7.0) | 11 (7.1) | n.s. |
| Lupus therapy at baseline | |||
| Mycophenolate, n (%) | 19 (13.6) | 38 (25.5) | 0.011 |
| Azathioprine, n (%) | 22 (15.7) | 21 (14.1) | n.s. |
| Ciclosporin A, n (%) | 3 (2.1) | 3 (2.0) | n.s. |
| Methotrexate, n (%) | 5 (3.6) | 9 (6.0) | n.s. |
| Antimalarials, n (%) | 113 (80.7) | 100 (67.1) | 0.009 |
| Cyclophosphamide, n (%) | 3 (2.1) | 1 (0.7) | n.s. |
| Rituximab, n (%) | 2 (1.4) | 1 (0.7) | n.s. |
| Prednisone dose, mean±SD, mg | 5.41±7.85 | 7.28±9.85 | n.s. |
| Cumulative average prednisone dose ≥180 mg/month | 24 (16.8) | 54 (36.5) | <0.001 |
| Lupus manifestations ever | |||
| Skin rashes, n (%) | 81 (57.4) | 100 (66.8) | 0.05 |
| Arthritis, n (%) | 98 (69.5) | 120 (79.5) | 0.05 |
| Serositis, n (%) | 26 (18.4) | 50 (33.1) | 0.004 |
| Glomerulonephritis, n (%) | 76 (53.9) | 92 (60.9) | n.s. |
| NP manifestations, n (%) | 14 (9.9) | 25 (16.6) | n.s. |
| Vasculitis, n (%) | 6 (4.3) | 28 (18.5) | 0.001 |
| Haematological involvement, n (%) | 46 (32.4) | 65 (43.0) | n.s. |
| Antiphospholipid Ab syndrome, n (%) | 10 (7.0) | 30 (19.9) | 0.001 |
| Lupus therapy ever | |||
| Methylprednisolone, intravenous, n (%) | 70 (5.0) | 99 (56.1) | n.s. |
| Mycophenolate, n (%) | 49 (34.5) | 78 (51.7) | 0.003 |
| Azathioprine, n (%) | 40 (28.2) | 57 (37.7) | n.s. |
| Ciclosporin A, n (%) | 15 (10.6) | 39 (25.8) | 0.001 |
| Methotrexate, n (%) | 16 (11.3) | 31 (20.5) | 0.031 |
| Antimalarials, n (%) | 131 (92.7) | 135 (89.4) | n.s. |
| Cyclophosphamide, n (%) | 31 (21.8) | 50 (33.1) | 0.031 |
| Rituximab, n (%) | 4 (2.8) | 18 (11.9) | 0.003 |
| Belimumab, n (%) | 10 (7.0) | 20 (13.1) | n.s. |
| Intravenous immunoglobulins, n (%) | 2 (1.4) | 10 (6.6) | 0.03 |
Ab, antibodies; ANA, antinuclear antibodies; anti-dsDNA, antidouble-stranded DNA; C3/C4, complement fractions; NP, neuropsychiatric; n.s., not significant; PGA, physician global assessment; SDI, Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index; SLE, systemic lupus erythematosus; SLEDAI-2K, SLE Disease Activity Index 2000.