Table 1.
Participant characteristics. Values are number (%) unless otherwise indicated.
| Characteristic | Patients, n = 198 | Controls, n = 299 | p |
|---|---|---|---|
| Age yrs, mean ± SD [range] | 39 ± 14 [15–76] | 41 ± 14 [16–75] | 0.087 |
| 0.9312 | |||
| Male | 19 (9.6) | 28 (9.4) | |
| Female | 179 (90.4) | 271 (90.6) | |
| < 0.0001 | |||
| African-American and other minorities | 126 (63.6) | 97 (32.4) | |
| White | 72 (36.4) | 202 (67.6) | |
| College graduate | 0.009 | ||
| Yes | 47 (23.7) | 104 (34.8) | |
| No | 151 (76.3) | 195 (65.2) | |
| Education | 0.003 | ||
| Did not complete high school | 36 (18.2) | 26 (8.7) | |
| Completed high school | 49 (24.8) | 63 (21.0) | |
| Some college | 66 (33.3) | 106 (35.5) | |
| Completed college | 47 (23.7) | 104 (34.8) | |
| Clinical features† | |||
| Arthritis | 143 (73.7) | — | |
| Pleuritis | 76 (39.6) | — | |
| Pericarditis | 26 (13.5) | — | |
| Seizures/Psychosis | 12 (6.2) | — | |
| Thrombocytopenia | 22 (11.4) | — | |
| Lupus nephritis | 47 (24.2) | — | |
| Anti-dsDNA antibodies | 50 (26.7) | — | |
†
Number of missing data: 5 for arthritis, 7 for pleuritis, 6 for pericarditis, 6 for seizures/psychosis, 6 for thrombocytopenia, 5 for lupus nephritis, and 12 for anti-dsDNA antibodies. Reasons for missing data were lack of permission for use of medical record data for the clinical failures data and non-participation in the blood sample collection for the anti-dsDNA antibody data.