Demographic and clinical characteristics of SLE group
| Age, median (IQR) (range) | 45 years (20) (22–64) |
| Sex, female n (%) | 82 (92%) |
| Ethnicity, n (%) | |
| White | 56 (63%) |
| Asian | 31 (35%) |
| Other | 2 (2%) |
| Disease duration: median (IQR) (range) | 15.0 years (17) (0.2–38.7) |
| Observation period: median (IQR) (range) | 5.5 years (7.6) (0–11.8) |
| ANA positive, n (%) | 94 (99%) |
| dsDNA positive, n (%) | 77 (81%) |
| Anti-Smith positive, n (%) | 14 (15%) |
| APLS antibodies (any), n (%) | 55 (58%) |
| APLS antibody triple positive, n (%) | 5 (5%) |
| APLS (syndrome), n (%) | 13 (14%) |
| History of cerebrovascular disease, n (%) | 12 (13%) |
| History of seizures, n (%) | 8 (8%) |
| History of cranial neuropathy, n (%) | 5 (5%) |
| History of substance use, n (%) | 13 (15%) |
| SLEDAI-2K at assessment: median (IQR) (range) | 3 (4) (0–12) |
| Time-adjusted mean SLEDAI-2K: median (IQR) (range) | 4 (3) (0–13) |
| SDI: median (IQR) (range) | 1 (2) (0–7) |
| Immunosuppressants, n (%) | |
| Hydroxychloroquine | 84 (88%) |
| Prednisolone | 34 (36%) |
| Mycophenolate | 33 (35%) |
| Azathioprine | 15 (16%) |
| Methotrexate | 14 (15%) |
| Leflunomide | 2 (2%) |
| Rituximab | 1 (1%) |
| Belimumab | 1 (1%) |
| Cyclophosphamide | 0 (0%) |
| Cognitive dysfunction (all thresholds pooled)*, n (%) | 49 (52%) |
| Severe cognitive dysfunction†, n (%) | 18 (19%) |
*Cognitive dysfunction defined by comparing to HC group data and meeting any of the three definition thresholds used.
†Severe cognitive dysfunction defined by meeting the most severe definition threshold used (at least two cognitive domains each >2 SD below the HC group mean).
APLS, anti-phospholipid syndrome (antibodies tested were anti-cardiolipin, Beta2glycoprotein and lupus anticoagulant); dsDNA, anti-double stranded DNA antibodies; HC, healthy control; SDI, Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index; SLEDAI-2K, Systemic Lupus Erythematosus Disease Activity Index 2000.