Baseline characteristics of the study population (n=177)
| Male, no. (%) | 141 (79.7) |
| Age, years | 39.0 (32.0, 46.0) |
| Disease duration, years | 9.0 (3.2, 16.1) |
| BMI, kg/m2 | 25.4 (22.6, 27.9) |
| HLA-B27 positive, no. (%) | 160 (90.4) |
| ASDAS | 3.9 (3.3, 4.6) |
| Time-averaged ASDAS | 2.0 (1.4, 2.8) |
| BASDAI (0–10) | 6.5 (5.3, 7.3) |
| Time-averaged BASDAI (0–10) | 3.0 (1.8, 4.9) |
| CRP, mg/L | 15.0 (7.0, 31.0) |
| Time-averaged CRP, mg/L | 3.7 (2.4, 8.1) |
| mSASSS | 13.1 (4.8, 29.5) |
Time-averaged values were calculated taking all available time points into account. Except if indicated otherwise, values are the median (IQR).
ASDAS, Ankylosing Spondylitis Disease Activity Score; BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; BMI, body mass index; CRP, C reactive protein; HLA, human leucocyte antigen; mSASSS, modified Stoke Ankylosing Spondylitis Spine Score.