Table 1 Demographic, clinical, and laboratory characteristics of SLE patients with and without AVN
|  | All (n = 4091) | SLE-AVN (n = 106) | SLE-non-AVN (n = 3985) | p value |
|---|---|---|---|---|
Demographic and clinical characteristics | ||||
 Female, N (%) | 3848 (94.1%) | 98 (92.5%) | 3750 (94.1%) | 0.478 |
 Age at SLE onset (y), median (25%, 75%IQR) | 27.51 (21.15, 36.15) | 25.76 (21.38, 30.81) | 27.58 (21.15, 36.26) | 0.060 |
 Disease duration at registration (y), median (25%, 75%IQR) | 2.09 (0.17, 5.92) | 2.01 (0.42, 5.58) | 2.09 (0.17, 5.92) | 0.919 |
SLEDAI-2Â K, median (25%, 75%IQR) | 3 (0, 8) | 2 (0, 7) | 3 (0, 8) | 0.318 |
Existing organ damage (SDI ≥ 1) at registration, N (%) | 663 (16.2%) | 38 (35.8%) | 625 (15.7%) |  < 0.001** |
 Cataract, N (%) | 23 (0.6%) | 3 (2.8%) | 20 (0.5%) | 0.021* |
 PAH, N (%) | 191 (4.7%) | 16 (15.1%) | 175 (4.4%) |  < 0.001** |
 Osteoporosis with fracture or vertebral collapse, N (%) | 14 (0.3%) | 2 (1.9%) | 12 (0.3%) | 0.049* |
 Premature gonadal failure, N (%) | 24 (0.6%) | 3 (2.8%) | 21 (0.5%) | 0.023* |
 Mucocutaneous, N (%) | 3271 (80.0%) | 89 (84.0%) | 3182 (79.8%) | 0.297 |
 Renal, N (%) | 1598 (39.1%) | 38 (35.8%) | 1560 (39.1%) | 0.492 |
 Neuropsychiatric, N (%) | 362 (8.8%) | 15 (14.2%) | 347 (8.7%) | 0.051 |
 Hematological, N (%) | 1904 (46.5%) | 60 (56.6%) | 1844 (46.3%) | 0.035* |
 Serositis, N (%) | 460 (11.2%) | 20 (18.9%) | 440 (11.0%) | 0.012* |
 Arthritis, N (%) | 2359 (57.7%) | 72 (67.9%) | 2287 (57.4%) | 0.030* |
 PAH, N (%) | 203 (5.0%) | 16 (15.1%) | 187 (4.7%) |  < 0.001** |
Laboratory results up until registration | ||||
 Hypocomplementemia, N (%) | 2934 (71.7%) | 82 (77.4%) | 2852 (71.6%) | 0.191 |
 ANA, N (%) | 4006 (97.9%) | 104 (98.1%) | 3902 (97.9%) | 1.000 |
 Anti-dsDNA, N (%) | 3138 (76.7%) | 81 (76.4%) | 3057 (76.7%) | 0.943 |
 Anti-Sm, N (%) | 3092 (75.6%) | 52 (49.1%) | 3007 (75.5%) | 0.263 |
 Anti-RNP, N (%) | 1247 (30.5%) | 49 (46.2%) | 1198 (30.1%) |  < 0.001** |
 Anti-SSA, N (%) | 1906 (46.6%) | 53 (50.0%) | 1853 (46.5%) | 0.476 |
 Anti-SSB, N (%) | 673 (16.5%) | 18 (17.0%) | 655 (16.4%) | 0.881 |
 Anti-rib P, N (%) | 642 (15.7%) | 25 (23.6%) | 617 (15.5%) | 0.024* |
 Positivity in aPLs, N (%) | 695 (17.0%) | 20 (18.9%) | 675 (16.9%) | 0.602 |
 Coombs, N (%) | 2188 (53.5%) | 52 (49.1%) | 2136 (53.6%) | 0.355 |
 GC usage, N (%) | 3505 (85.7%) | 103 (97.2%) | 3402 (85.4%) | 0.001** |
 GC maximum dose at registration(mg), median (25%, 75%IQR) | 10.0 (5.0, 35.0) | 13.8 (10.0, 50.0) | 10.0 (3.8, 30.0) |  < 0.001** |
 High dose GC at registration, N (%) | 468 (11.4%) | 23 (21.7%) | 445 (11.2%) | 0.001** |
 Hydroxychloroquine, N (%) | 3199 (78.2%) | 76 (71.7%) | 3123 (78.4%) | 0.101 |
 Immunosuppressants, N (%) | 2561 (62.6%) | 73 (68.9%) | 2488 (62.4%) | 0.177 |