Table 1.
Demographic features of the study participants*
| Patients with early SSc (n = 60) |
Patients with late SSc (n = 14) |
Healthy controls (n = 21) |
SLE patients (n = 17) |
Total (n = 112) |
|
|---|---|---|---|---|---|
| Age at enrollment, mean ± SD years | 48.94 ± 13.63 | 50.12 ± 13.37 | 53.53 ± 16.72 | 38.5 ± 12.64† | 48.37 ± 14.62 |
| No. of women/no. of men | 50/10 | 9/5 | 17/4 | 16/1 | 92/20 |
| Race | |||||
| Caucasian | 33 (55) | 7 (50) | 13 (61.9) | 6 (35.3) | 59 (52.7) |
| African American | 13 (21.7) | 4 (28.6) | 4 (19) | 2 (11.8) | 23 (20.5) |
| Hispanic | 12 (20) | 2 (14.3) | 4 (19) | 8 (47.1) | 26 (23.2) |
| Other | 2 (3.3) | 1 (7.1) | 0 | 1 (5.9) | 4 (3.6) |
| SSc-related autoantibodies | |||||
| ACAs | 9 (15) | – | – | – | – |
| Antitopoisomerase | 10 (16.7) | 14 (100) | – | – | – |
| Anti–RNAP III | 15 (25) | – | – | – | – |
| Anti–U1 RNP | 4 (6.7) | – | – | – | – |
*
Except where indicated otherwise, values are the number (%) of subjects. ACAs = anticentromere antibodies; anti–RNAP III = anti–RNA polymerase III.
†
The patients with systemic lupus erythematosus (SLE) were significantly younger than the patients with early systemic sclerosis (SSc), the patients with late SSc, and the healthy controls (P = 0.006, P = 0.0191, and P = 0.004, respectively).