Table 1 Patient characteristics at baseline (start of methotrexate)
| Â | persistent oligoJIA | extended oligoJIA | RF negative polyarthritis |
|---|---|---|---|
patients [n] | 370 | 221 | 467 |
Female gender [n, %] | 244 (66) | 161 (73) | 370 (79) |
age at onset [years] | |||
 mean, +/− SD | 6.4 +/− 4.3 | 5.2 +/− 3.7 | 8.4 +/−  4.7 |
 median, (IQR) | 5.0 (2.6; 9.75) | 4.2 (2.2;7.4) | 8.9 (4.03;12.4) |
age at MTX start [years] | |||
 mean, +/− SD | 8.7 +/− 4.7 | 8.5 +/−  4.3 | 9.7 +/−  4.9 |
 median, (IQR) | 8.1 (4.5;12.7) | 8.6 (0.6;4.4) | 10.3 (5.7;14) |
disease duration [years] | |||
 mean, +/− SD | 2.4 +/− 2.9 | 3.2 +/− 3.7 | 1.3 +/−  2 |
 median, (IQR) | 1.1 (0.5;3.1) | 1.6 (0.64;4.41) | 0.5 (0.26;1.44) |
MTX starting dose [mg/m2] | |||
 median, (IQR) | 12.6 (11;14.1) | 12.1 (10.5;13.8) | 12.5 (10.9;14) |
Pretreatment | |||
 NSAR [n, %] | 315 (85.1) | 195 (88.2) | 394 (84.4) |
 i.a. Steroids [n, %] | 186 (50.3) | 85 (38.46) | 100 (4.28) |
concomitant treatment at enrolment, [n, %] | |||
 oral steroids [n, %] | 48 (13) | 33 (15) | 147 (32) |
 steroids pulse therapy last 3 month [n, %] | 6 (1.6) | 3 (1.4) | 20 (4.3) |
 conventional DMARDs, [n, %] | 9 (2.4) | 9 (4.1) | 10 (2.1) |
ANA- positive [n, %] | 216 (58.49) | 146 (66.1) | 240 (51.4) |
Uveitis at enrolment [n, %] | 49 (13.2) | 27 (12.2) | 9 (1.9) |
Active arthritis at enrolement [n, %] | 329 (88.9) | 209 (94.6) | 443 (94.9) |
number of active joints | |||
 mean +/−SD | 2.1 +/− 1.8 | 4.1 +/− 4.1 | 11.1 +/− 10.3 |
 median (IQR) | 3 (2; 20) | 5 (3; 34) | 15 (8; 55) |
ESR > 20 mm/1 h [n, %] | 128 (37.2) | 83 (41.9) | 197 (45.4) |
CRP > 5 mg/l [n, %] | 117 (33.7) | 91 (45.0) | 217 (48.5) |
JADAS 10 mean, +/−SD [0–14] median (IQR) | 9.9 +/− 4.8 9.9 (6.3; 13.2) | 11.8 +/− 4.9 11.8 (8.5; 15.2) | 16.7 +/− 6.3 21.2 (17.0; 21.2) |