Baseline comparison of patients with or without major infections in the first 4 months
| Training set n=352 | Testing set n=142 | |||||
| Control n=303 | Major infection within 4 months n=49 | P value | Control n=128 | Major infection within 4 months n=14 | P value | |
| Demographic data | ||||||
| Female | 266 (88) | 38 (78) | 0.0527 | 118 (92) | 10 (71) | 0.0134 |
| Age (years) | 35±14 | 41±15 | 0.0080 | 35±14 | 46±15 | 0.0090 |
| SLE activity | ||||||
| SLEDAI score | 10±5 | 17±7 | <0.0001 | 10±5 | 17±5 | <0.0001 |
| Neuropsychiatric involvement | 44 (15) | 11 (22) | 0.1562 | 10 (8) | 4 (29) | 0.0134 |
| Pulmonary hypertension | 23 (8) | 6 (12) | 0.2716 | 7 (5) | 3 (21) | 0.0267 |
| Gastrointestinal involvement | 24 (8) | 9 (18) | 0.0199 | 8 (6) | 1 (7) | 0.8964 |
| Serositis | 97 (32) | 20 (41) | 0.2249 | 19 (15) | 8 (57) | 0.0001 |
| Nephritis | 113 (37) | 35 (71) | <0.0001 | 52 (41) | 7 (50) | 0.4992 |
| Laboratory tests | ||||||
| Anti-ds-DNA+ | 203 (67) | 36 (73) | 0.3679 | 98 (77) | 13 (93) | 0.0793 |
| Low complement 3 | 256 (84) | 45 (92) | 0.1752 | 104 (81) | 13 (93) | 0.2790 |
| Leucocyte count <3×109/L | 36 (12) | 7 (14) | 0.6334 | 17 (13) | 4 (29) | 0.1260 |
| Lymphocyte count <0.8×109/L | 85 (28) | 34 (69) | <0.0001 | 38 (30) | 10 (71) | 0.0017 |
| Platelet count <100×109/L | 55 (18) | 21 (43) | <0.0001 | 20 (16) | 6 (43) | 0.0124 |
| Haemoglobin <110 g/L | 191 (63) | 36 (73) | 0.1568 | 39 (30) | 10 (71) | 0.0022 |
| IgG <7 g/L | 13 (4) | 3 (6) | 0.5679 | 5 (4) | 3 (21) | 0.0069 |
| Serum creatinine >104 µmol/L | 19 (6) | 22 (45) | <0.0001 | 8 (6) | 3 (21) | 0.0437 |
| Treatments received before enrolment | ||||||
| Prednisone | 177 (58) | 36 (73) | 0.0455 | 71 (55) | 10 (71) | 0.2521 |
| Hydroxychloroquine | 153 (50) | 17 (37) | 0.0400 | 49 (38) | 5 (36) | 0.8510 |
| Immunosuppressants | 42 (14) | 11 (22) | 0.1189 | 18 (14) | 6 (43) | 0.0063 |
| Cyclophosphamide | 19 (6) | 7 (14) | 0.0466 | 5 (4) | 4 (29) | 0.0003 |
| Mycophenolate mofetil | 11 (4) | 2 (4) | 0.8765 | 5 (4) | 1 (7) | 0.5625 |
| Ciclosporin A | 7 (2) | 1 (2) | 0.9090 | 0 (0) | 0 (0) | / |
| Methotrexate | 2 (1) | 0 (0) | 0.5685 | 1 (1) | 1 (7) | 0.0551 |
| Rituximab | 1 (0.3) | 0 (0) | 0.6872 | 0 (0) | 0 (0) | / |
| Other | 2 (1) | 1 (2) | 0.3293 | 7 (5) | 0 (0) | 0.3695 |
| Treatments received within 1 month of enrolment | ||||||
| Maximum prednisone (mg/day) | 187±217 | 306±185 | 0.0003 | 156±163 | 297±215 | 0.0035 |
| Methylprednisolone pulses | 51 (17) | 22 (45) | <0.0001 | 16 (11) | 7 (50) | 0.0003 |
| Cumulated prednisone (mg/first month) | 1845±787 | 2289±656 | 0.0002 | 1764±642 | 2121±998 | 0.0795 |
| Immunosuppressants | 227 (75) | 27 (55) | 0.0041 | 103 (73) | 11 (79) | 0.8655 |
| Cyclophosphamide | 79 (26) | 12 (24) | 0.8144 | 29 (20) | 4 (29) | 0.6188 |
| Mycophenolate mofetil | 52 (17) | 5 (10) | 0.2200 | 22 (15) | 4 (29) | 0.2957 |
| Ciclosporin A | 11 (4) | 3 (6) | 0.4076 | 1 (1) | 0 (0) | 0.7400 |
| Methotrexate | 18 (6) | 0 (0) | 0.0799 | 6 (4) | 1 (7) | 0.6870 |
| Rituximab | 48 (16) | 6 (12) | 0.5169 | 28 (20) | 1 (7) | 0.1942 |
| Other | 19 (6) | 1 (2) | 0.2354 | 17 (12) | 1 (7) | 0.5122 |
| All-cause deaths | 7 (2) | 18 (37) | <0.0001 | 0 (0) | 4 (29) | <0.0001 |
Data are presented as mean±SD for continuous variables and number (frequency) (%) for categorical variables. Methylprednisolone pulses: ≥500 mg/day intravenously for 3 days. Other immunosuppressants included tacrolimus, azathioprine, iguratimod and leflunomide.
ds-DNA, double-stranded DNA; SLEDAI, SLE Disease Activity Index.