Table 1.
Features of patients from both RA cohorts
| Dartmouth Established RA Cohort Lebanon, NH, USA | Sherbrooke Early RA Cohort Sherbrooke, QC, Canada | |||
|---|---|---|---|---|
| Seronegative | Seropositive | Seronegative | Seropositive | |
| Patients, % of cohort (n) | 21% (45) | 79% (167) | 49% (165) | 51% (171) |
| Age, mean ± SD years (range) | 57 ± 12 (29-74) | 58 ± 11 (19-91) | 62 ± 16 (19-89) | 57 ± 13 (19-89) |
| Women, % (n) | 67% (30) | 71% (119) | 64% (106) | 60% (103) |
| Years of symptoms, mean ± SD (unavailable for much of Dartmouth cohort) | 9% with <1 year from disease onset | 14% with <1 year from disease onset | 0.44 ± 0.43 | 0.45 ± 0.33 |
| Range of disease duration | From new onset to >20 years | From new onset to >20 years | 0-12 months from disease onset | 0-12 months from disease onset |
| Anti-CarP level, mean ± SD | 15.5 ± 54.1 | 70.2 ± 184.1 | 5.8 ± 12.6 | 34.9 ± 88.0 |
| DAS28-CRP, mean ± SD | Unavailable | Unavailable | 5.1 ± 1.5 | 5.0 ± 1.4 |
| CRP mg/L, mean ± SD | Unavailable | Unavailable | 24.4 ± 33.9 | 26.5 ± 35.7 |
| Anti-CCP units/ml, mean ± SD | N/A | 419 ±337 | N/A | 200 ± 136 |
| IgM RF IU/ml, mean ± SD | N/A | 135 ± 76 | N/A | 170 ± 79 |
| Anti-Sa status, % positive (n) | N/A | 57% (90/158) | 2% (3/134) | 51% (72/142) |
| Total IgG mg/ml, mean ± SD | 16 ± 11.6 | 17.6 ± 10.0 | 9.2 ± 2.5 | 21.1 ± 7.6 |
| CXCL13 pg/ml, mean ± SD | 116 ±76 | 1938 ± 6154 | 313 ± 1460 | 1490 ± 2460 |
| CXCL10 pg/ml, mean ± SD | 164 ± 207 | 392 ± 1121 | 118 ± 308 | 168 ± 307 |
| Shared epitope % positive (n) | 46% (6/13) | 83% (89/107) | 26% (33/128) | 50% (70/141) |
| RA treatment | Wide range from none to biologic therapy | Wide range from none to biologic therapy | Predominantly DMARD and corticosteroid naive | Predominantly DMARD and corticosteroid naive |
In the Dartmouth seronegative patients, only 28 of 45 patients had measured values for total IgG, CXCL13, and CXCL10. When percentages are given but not all patients in that group were tested (i.e. Shared epitope), the “n” is displayed as a fraction representing number of positive over number of those tested. Classification by serostatus and Anti-Sa reactivity was determined using different methods for the two cohorts (see Materials and Methods section).