Table 1.
Demographic and clinical characteristics of the four study groups: systemic lupus erythematosus (SLE), incomplete lupus (ILE), first-degree relatives (FDR), non-autoimmune controls (NC).
| NC | FDR | ILE | SLE | P-value‡ | |
|---|---|---|---|---|---|
| Number | 11 | 22 | 24 | 27 | – |
| % Female | 92 | 85 | 93 | 91 | 0.79 |
| % African American | 23 | 20 | 17 | 43 | 0.60 |
| % Hispanic | 15 | 10 | 17 | 23 | 0.76 |
| Age (years)* | 43 ± 5 | 46 ± 4 | 47 ± 3 | 39 ± 3 | 0.29 |
| ANA (EU)*† | 14 ± 3 | 37 ± 11 | 105 ± 18 | 113 ± 12 | <0.0001 |
| dsDNA (EU)* | n.d. | 132 ± 46 | 156 ± 44 | 317 ± 99 | 0.0113 |
*
Values for age and antibodies are expressed as mean and standard error of the mean.
†
Anti-nuclear antibody (ANA) and extractable nuclear autoantibodies (ENA) values are expressed as enzyme-linked immunosorbent assay units (EU).
‡
P-values were calculated comparing the groups using χ2 (female, African American, Hispanic), one-way analysis of variance (age, ANA), t-test (criteria) or Kruskal–Wallis (dsDNA) test, as appropriate. n.d., not done.