Clinical manifestations, serological features and comorbidities
| Total | Male | Female | P value | |
| Initial disease manifestations, n (%) | ||||
| Arthralgias/arthritis | 232/415 (55.9) | 30/51 (58.8) | 202/364 (55.5) | 0.65 |
| Skin rash | 165/415 (39.8) | 18/51 (35.3) | 147/364 (40.4) | 0.49 |
| Haematological abnormalities | 123/408 (30.1) | 12/51 (23.5) | 111/357 (35.0) | 0.27 |
| Constitutional symptoms | 85/414 (20.5) | 14/51 (27.4) | 71/363 (19.6) | 0.19 |
| Raynaud’s phenomenon | 75/409 (18.3) | 6/50 (12) | 69/359 (19.2) | 0.22 |
| Renal disease | 62/415 (14.9) | 10/51 (19.6) | 52/364 (14.3) | 0.32 |
| Serositis | 34/415 (8.2) | 8/51 (15.7) | 26/364 (7.1) | 0.037 |
| NPSLE | 17/409 (4.2) | 4/50 (8) | 13/359 (3.6) | 0.21 |
| Cumulative* disease manifestations, n (%) | ||||
| Articular | 313/410 (76.3) | 36/51 (70.6) | 177/360 (49.2) | 0.44 |
| Mucocutaneous | 263/410 (64.1) | 28/50 (56) | 235/360 (65.3) | 0.2 |
| Haematological | 262/407 (64.4) | 23/50 (46) | 239/357 (66.9) | 0.004 |
| Renal | 183/411 (44.5) | 22/51 (43.1) | 161/360 (44.7) | 0.83 |
| Serosal | 91/406 (22.4) | 9/48 (18.7) | 82/358 (22.9) | 0.52 |
| NPSLE | 43/408 (10.5) | 7/49 (14.3) | 36/359 (10) | 0.36 |
| APS | 70/409 (17.1) | 13/46 (28.3) | 57/363 (15.7) | 0.04 |
| Sjögren’s syndrome | 29/406 (7.1) | 5/45 (11.1) | 24/361 (6.6) | 0.27 |
| Disease onset-renal manifestations (years) | ||||
| Mean±SD | 2.7±4.9 | 3±6.5 | 2.6±4.7 | 0.44 |
| Median (IQR 25%–75%) | 0 (0–3) | 0 (0–5) | 0 (0–3) | |
| Type of renal involvement, n (%) | ||||
| Minimal lesions | 1/147 (0.7) | 1/18 (5.5) | 0/129 (0) | n.s. |
| Type I | 3/147 (2) | 1/18 (5.5) | 2/129 (1.5) | n.s. |
| Type II | 17/147 (11.6) | 1/18 (5.5) | 16/129 (12.4) | n.s. |
| Type III | 28/147 (19) | 2/18 (11.1) | 26/129 (20.1) | n.s. |
| Type IV | 85/147 (57.8) | 11/18 (61.1) | 74/129 (57.4) | n.s. |
| Type V | 8/147 (5.4) | 2/18 (11.1) | 6/129 (4.6) | n.s. |
| Mixed | 5/147 (3.4) | 0/18 (0) | 5/129 (3.9) | n.s. |
| Immunological characteristics, n (%) | ||||
| ANA+ | 417/417 (100) | 51/51 (100) | 366/366 (100) | |
| ENA+ | 232/409 (56.7) | 29/51 (56.9) | 203/358 (56.7) | 0.98 |
| Anti-dsDNA+ | 310/411 (75.4) | 36/51 (70.6) | 274/360 (76.1) | 0.39 |
| Anti-Ro-SSA or La-SSB+ | 145/401 (36.2) | 19/50 (38) | 126/351 (35.9) | 0.77 |
| Anti-Sm+ | 60/403 (14.9) | 10/50 (20) | 50/353 (14.2) | 0.28 |
| Anti-RNP+ | 103/404 (25.5) | 11/51 (21.6) | 92/353 (26) | 0.49 |
| aPL+ | 168/410 (41) | 25/50 (50) | 143/360 (39.7) | 0.17 |
| LAC+ | 100/396 (25.2) | 17/49 (34.7) | 83/347 (23.9) | 0.1 |
| Comorbidities, n (%) | ||||
| Osteoporosis | 88/387 (22.7) | 8/46 (17.4) | 80/341 (23.5) | 0.6 |
| Hypertension | 113/411 (26.7) | 17/50 (34) | 96/361 (26.6) | 0.27 |
| Type 2 diabetes | 15/409 (3.7) | 0/51 (0) | 15/358 (3.6) | 0.14 |
| Dyslipidaemia | 69/410 (16.8) | 8/51 (15.7) | 61/359 (16.9) | 0.82 |
aPL antibodies include anticardiolipin IgG and IgM, antibeta-2-glycoprotein I IgG and IgM.
Statistically significant p-values are in bold.
*After disease onset.
aPL, antiphospholipid; APS, antiphospholipid syndrome; dsDNA, double stranded DNA; ENA, extractable nuclear antigen; LAC, lupus anticoagulant; NPSLE, neuropsychiatric SLE; n.s., not significant; RNP, ribonucleoprotein; Sm, Smith.