Table 2

Association (represented as OR and 95% CI from the logistic regression analysis) between disease activity parameters (time-averaged ASDAS, CRP, BASDAI and PG) and radiographic spinal progression over 2 years in patients with early axial spondyloarthritis

Time-averaged* parametersUnadjusted model with ASDASAdjusted model with ASDAS†Adjusted model with CRP†Adjusted model with BASDAI†Adjusted model with PG†Adjusted model with BASDAI, PG and CRP†
Outcome: mSASSS progression by ≥2 points over 2 years
 ASDAS1.64 (1.03–2.62)1.80 (1.04–3.13)
 CRP1.04 (0.99–1.08)1.03 (0.98–1.07)
 BASDAI1.12 (0.87–1.45)0.79 (0.47–1.31)
 PG1.21 (0.97–1.51)1.42 (0.90–2.22)
 R2 of the model0.0440.2690.2370.2490.2550.273
Outcome: syndesmophyte formation/progression over 2 years
 ASDAS2.62 (1.46–4.68)2.45 (1.26–4.77)
 CRP1.07 (1.01–1.13)1.06 (1.01–1.12)
 BASDAI1.25 (0.94–1.65)0.93 (0.51–1.70)
 PG1.30 (1.01–1.69)1.31 (0.76–2.27)
 R2 of the model0.1290.3670.3170.3530.3340.376
  • *Over 2 years, up to five time-points.

  • †Adjusted for the presence of syndesmophytes at baseline, smoking status and NSAIDs intake score over 2 years.

  • ASDAS, Ankylosing Spondylitis Disease Activity Score; BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; CRP, C reactive protein; mSASSS, modified Stoke Ankylosing Spondylitis Spine Score; NSAIDs, non-steroidal anti-inflammatory drugs; PG, patients global assessment of disease activity.