Table 1.
Study participant characteristics
| Healthy control subjects (n = 20) | ANA+ no symptoms (n = 38) | UCTD (n = 28) | SARD (n = 58) | SSc (n = 26) | SLE (n = 6) | SS (n = 23) | DM/MCTD (n = 3) | |
|---|---|---|---|---|---|---|---|---|
| Female sex, n (%) | 18 (90) | 37 (97.4) | 27 (96.4) | 54 (93.1) | 24 (92.3) | 6 (100) | 21 (91.3) | 3 (100) |
| Age, years, mean ± SD | 41 ± 12.4 | 44.1 ± 14.3 | 47.5 ± 15.4 | 51.5 ± 14.4 | 52.8 ± 14.7 | 39 ± 12.3 | 54.8 ± 12.7 | 39.3 ± 6.6 |
| Anti-malarials, n (%) | 0 (0) | 5 (13.2) | 4 (14.3) | 7 (12.1) | 2 (7.7) | 2 (33.3) | 2 (8.7) | 1 (33.3) |
| Ethnicity, n (%) | ||||||||
| Caucasian | 9 (45) | 23 (60.5) | 20 (71.4) | 41 (70.7) | 18 (69.2) | 4 (66.7) | 17 (73.9) | 2 (66.7) |
| African | 1 (5) | 4 (10.5) | 3 (10.7) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) |
| Asian | 1 (5) | 1 (2.6) | 3 (10.7) | 3 (5.2) | 1 (3.8) | 0 (0) | 2 (8.7) | 0 (0) |
| Southeast Asian | 3 (15) | 5 (13.2) | 0 (0) | 7 (12.1) | 3 (11.5) | 2 (33.3) | 2 (8.7) | 0 (0) |
| Filipino | 4 (20) | 1 (2.6) | 1 (3.6) | 4 (6.9) | 3 (11.5) | 0 (0) | 0 (0) | 1 (33.3) |
| Hispanic | 1 (5) | 1 (2.6) | 1 (3.6) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) |
| Other | 1 (5) | 3 (7.9) | 0 (0) | 3 (5.2) | 1 (3.8) | 0 (0) | 2 (8.7) | 0 (0) |
| Specific antibodies, n (%) | ||||||||
| dsDNA | 0 (0) | 2 (5.3) | 4 (14.3) | 9 (15.5) | 3 (11.5) | 2 (33.3) | 3 (13.0) | 1 (33.3) |
| Ro | 0 (0) | 7 (18.4) | 8 (28.6) | 30 (51.7) | 4 (15.4) | 3 (50) | 23 (100) | 0 (0) |
| La | 0 (0) | 2 (5.3) | 4a (14.3) | 18 (31.0) | 0 (0) | 1 (16.7) | 17 (73.9) | 0 (0) |
| Sm | 0 (0) | 0 (0) | 2 (7.1) | 3 (5.2) | 0 (0) | 2 (33.3) | 0 (0) | 1 (33.3) |
| Sm/RNP | 0 (0) | 0 (0) | 5 (17.9) | 6 (10.3) | 2 (7.7) | 2 (33.3) | 0 (0) | 2 (66.7) |
| RNP | 0 (0) | 4 (10.5) | 4 (14.3) | 8 (13.8) | 2 (7.7) | 3 (50) | 1 (4.3) | 2 (66.7) |
| Scl-70 | 0 (0) | 0 (0) | 2 (7.1) | 10 (17.2) | 7 (26.9) | 1 (16.7) | 2 (8.7) | 0 (0) |
| Jo-1 | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) |
| Centromere | 0 (0) | 1 (2.6) | 1 (3.6) | 17 (29.3) | 14 (53.8) | 1 (16.7) | 1 (4.3) | 1 (33.3) |
| Chromatin | 0 (0) | 2 (5.3) | 4 (14.3) | 6 (10.3) | 1 (3.8) | 3 (50) | 0 (0) | 2 (66.7) |
Abbreviations: ANA Anti-nuclear antibody, UCTD Undifferentiated connective tissue disease, SARD Systemic autoimmune rheumatic disease, SSc Systemic sclerosis, SS Sjögren’s syndrome, SLE Systemic lupus erythematosus, DM Dermatomyositis, MCTD Mixed connective tissue disease, dsDNA Double-stranded DNA, Sm Smith, RNP Ribonuclear protein
aAll patients that were anti-La antibody positive were anti-Ro antibody positive, except for 1 patient with UCTD