Clinical characteristics of the patients with SLE
| Discovery cohort (Sweden) | Replication cohort (UCSF) | P values | |
| Number of patients | 1045 | 1043 | |
| Female | 910 (87) | 959 (92) | <0.001 |
| Age at diagnosis (year) | 36±16 | 35±14 | 0.12 |
| Age at study (year) | 51±16 | 44±13 | <0.001 |
| PE/DVT | 153 (15) | 91 (10) | <0.001 |
| MI/angina* | 107 (10) | 39 (4) | <0.001 |
| Stroke/TIA† | 96 (12) | 55 (5) | <0.001 |
| Stroke/MI‡ | 133 (16) | 84 (8) | <0.001 |
| Antiphospholipid antibodies§ | 292(31) | 374(41) | <0.001 |
| ACR criteria | |||
| 1) Malar rash | 576 (55) | 424 (41) | <0.001 |
| 2) Discoid rash | 244 (23) | 60 (6) | <0.001 |
| 3) Photosensitivity | 699 (67) | 816 (78) | <0.001 |
| 4) Oral ulcers | 245 (23) | 282 (27) | 0.06 |
| 5) Arthritis | 823 (79) | 727 (70) | <0.001 |
| 6) Serositis | 459 (44) | 269 (26) | <0.001 |
| 7) Renal disorder | 349 (33) | 237 (23) | <0.001 |
| 8) Neurological disorder | 104 (10) | 89 (9) | 0.26 |
| 9) Haematological disorder | 630 (60) | 638 (61) | 0.72 |
| 10) Immunological disorder | 711 (68) | 640 (61) | 0.001 |
| 11) Positive ANA | 1026 (98) | 954 (91) | <0.001 |
| SDI¶ median (range) | 1 (0–13) | NA | |
| BILD** median (range) | NA | 2 (0–13) |
Data are number (%) or mean±SD.
Categorical variables were compared with χ 2 test and continuous variables by Student’s unpaired t-test.
*Data regarding angina were available only for the discovery cohort.
†Missing data for 231 patients in the discovery cohort, data regarding TIA were only available for the discovery cohort.
‡Missing data for 231 patients in the discovery cohort.
§Discovery cohort, at least one positive test for anticardiolipin (IgM or IgG) or anti-β2 glycoprotein-I (IgG), data available for 952 patients. Replication cohort, at least one positive test for lupus anticoagulant, anticardiolipin (IgM or IgG) or anti-β2 glycoprotein-I (IgM or IgG), data available for 907 patients.
¶SDI.47
**BILD48 data available for 514 patients.
ACR criteria, American College of Rheumatology classification criteria for SLE (manifestations until end of follow-up);18 ANA, antinuclear antibodies BILD, Brief Index of Lupus Damage; DVT, deep vein thrombosis; MI, myocardial infarction; NA, data not available; PE, pulmonary embolism; SDI; Systemic Lupus International Collaborating Clinics /ACR damage index for SLE; SLE, systemic lupus erythematosus; TIA, transient ischaemic attack; UCSF, University of California, San Francisco.