Demographics and characteristics of subjects with SLE and healthy controls (HC)
| Subject demographics and characteristics | SLE (N=74) | HC (N=74) | P value (SLE vs HC) |
| Age (years) Mean±SD (range) | 37.6±9.6 (22–57) | 36.2±9.4 (18–55) | 0.38 |
| Ethnicity, n (%) | |||
| Hispanic/Latino | 13 (18) | 14 (19) | 0.83 |
| Race, n (%) | |||
| Black | 45 (61) | 41 (55) | 0.79 |
| White | 16 (22) | 19 (26) | |
| Other | 13 (18) | 14 (19) | |
| Education level (years) Mean±SD (range) | 15.7±2.4 (10–22) | 16.2±2.5 (8–21) | 0.20 |
| Computer experience, n (%) | 0.02* | ||
| Extensive | 20 (27) | 34 (46) | |
| Moderate | 41 (55) | 35 (47) | |
| Some | 13 (18) | 5 (7) | |
| Employment status, n (%) | |||
| Unemployed | 23 (31) | 7 (10) | <0.01 |
| Self-reported cognitive dysfunction, n (%) | 33 (45) | 2 (3) | <0.01 |
| Disease duration† Mean±SD (range) | 12.3±8.4 (1–38) | – | – |
| SELENA-SLEDAI score Mean±SD (range) | 5.4±5.0 (0–29) | – | – |
| Prednisone dose, mg/day Median (Q1–Q3) (range) | 2.8 (0.0–10.0) (0–75) | – | – |
| Current hydroxychloroquine use, n (%) | 55 (74) | – | – |
| Current immunosuppressant use, n (%) | 36 (49) | – | – |
| Anti-dsDNA positive (≥30 IU/mL), n (%) | 52 (70) | – | – |
| C3 low (<81 mg/dL), n (%) | 29 (39) | – | – |
| C4 low (<13 mg/dL), n (%) | 25 (34) | – | – |
| Anticardiolipin (IgG, IgM or IgA) positive (≥40 MPL), n (%) | 5 (7) | – | – |
| White cell count n (%) less than the lower limit of the normal range (3.8 x 109/L) | 25 (34) | 8 (11) | 0.01 |
| Haemoglobin n (%) less than the lower limit of the normal range (115 g/L) | 39 (53) | 9 (12) | <0.01 |
| Platelet count‡ n (%) greater than the upper limit of the normal range (400 x 109/L) | 11 (15) | 2 (3) | 0.02 |
| Protein/creatinine ratio n (%) with a ratio >0.5 | 11 (15) | – | – |
All data were collected at the time of evaluation, and are reported as either a mean or median along with an SD or IQR, or as a frequency (%).
*Extensive and some (p=0.009).
†Disease duration, N=74: ≤2 years (N=8, mean±SD=1.8±0.5); disease duration >2 and <10 years (N=24, 5.8±1.9); disease duration ≥10 years (N=42, 18.0±6.7).
‡Platelet count, SLE (n=74): <150 K/µL (N=2, mean±SD=140.5±2.1); ≥150 and ≤400 (N=61, 255.5±59.5); >400 (N=11, 483.2±87.3); HC (N=74): <150 K/µL (N=0); ≥150 and ≤400 (N=72, 266.1±58.7); >400 (N=2, 435.0±32.5).
dsDNA, double-stranded DNA; HC, healthy controls.