Table 2.
Clinical characteristics of time intervals classified according to cDMARD treatment.
| Variable | Total intervals (n = 1759) |
On-cDMARD interval (n = 732) | Off-cDMARD interval (n = 1027) | |
|---|---|---|---|---|
| No. with data | Value, mean (SD) or n (%) | |||
| Age at the interval start, mean (SD), years | 1759 | 30.84 (8.61) | 31.56 (9.17) | 30.33 (8.15) |
| Female, n (%) | 1759 | 221 (12.6%) | 113 (15.4) | 108 (10.5) |
| HLA-B27 positive, n (%) | 1749 | 1695 (96.9%) | 702 (96.7) | 993 (97.1) |
| Eye involvement, n (%) | 1596 | 604 (37.8%) | 258 (38.7) | 346 (37.2) |
| Peripheral joint involvement, n (%) | 1599 | 907 (56.7%) | 454 (68.4) | 453 (48.4) |
| ESR at the interval start, mean (SD), mm/hr | 1740 | 24.22 (23.50) | 29.16 (27.68) | 20.75 (19.32) |
| CRP at the interval start, mean (SD), mg/dL | 1740 | 1.52 (1.46) | 1.85 (1.88) | 1.28 (1.00) |
| BASDAI at the interval start, mean (SD) | 682 | 3.55 (1.82) | 3.93 (1.82) | 3.39 (1.80) |
| NSAIDs*, n (%) | 1759 | 1022 (58.1%) | 486 (66.4) | 536 (52.2) |
| Glucocorticoids*, n (%) | 1759 | 118 (6.7%) | 101 (13.8) | 17 (1.7) |
| cDMARDs*, n (%) | 1759 | 732 (41.6%) | SSZ, n = 704 (96.2) MTX, n = 146 (19.9) |
– |
| mSASSS change per year, mean (SD) | 1759 | 0.65 (1.42) | 0.55 (1.36) | 0.73 (1.46) |
*
Considered to be sustained during the interval if they were prescribed during more than half of the interval.
BASDAI, Bath Ankylosing Spondylitis Activity Index; cDMARD, conventional disease-modifying antirheumatic drug; CRP, C-reactive protein; ESR, erythrocyte sedimentation rate; HLA, human leukocyte antigen; mSASSS, modified Stoke Ankylosing Spondylitis Spine Score; MTX, methotrexate; NSAIDs, non-steroidal anti-inflammatory drugs; SD, standard deviation; SSZ, sulfasalazine.