Table 5.
The ordinal logistic regression analysis of clinical features # independently associated with the grade of sacroiliac joint damage
| Characteristics | Based on the left sacroiliac joint damage | Based on the right sacroiliac joint damage | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Complex model 1 | Simplified model 2 | Complex model 3 | Simplified model 4 | |||||||||
| AOR | 95% CI | p value | AOR | 95% CI | p value | AOR | 95% CI | p value | AOR | 95% CI | p value | |
| AxSpA duration, per year | 1.187 | 1.089–1.294 | 0.000 | 1.180 | 1.086–1.283 | 0.000 | 1.188 | 1.090–1.295 | 0.000 | 1.190 | 1.096–1.293 | 0.000 |
| ESR, per mm/h | 1.003 | 0.981–1.025 | 0.794 | 1.003 | 0.982–1.025 | 0.755 | 1.001 | 0.981–1.022 | 0.905 | 1.003 | 0.982–1.024 | 0.781 |
| CRP, per mg/l | 1.038 | 0.999–1.079 | 0.058 | 1.018 | 0.991–1.046 | 0.194 | 1.025 | 0.987–1.065 | 0.196 | 1.008 | 0.981–1.036 | 0.576 |
| Total back pain, per score | 1.428 | 1.040–1.962 | 0.028 | 1.246 | 0.975–1.591 | 0.078 | 1.315 | 0.959–1.803 | 0.089 | 1.166 | 0.916–1.484 | 0.212 |
| PGA of disease activity, per score | 1.040 | 0.784–1.380 | 0.786 | 0.975 | 0.746–1.275 | 0.856 | 1.023 | 0.780–1.342 | 0.868 | 0.970 | 0.751–1.252 | 0.815 |
| Pain and swelling of peripheral arthritis, per score | 1.517 | 0.795–2.897 | 0.207 | 1.356 | 0.725–2.534 | 0.341 | 1.858 | 0.978–3.532 | 0.059 | 1.657 | 0.890–3.084 | 0.111 |
| Duration of morning stiffness, per score | 0.723 | 0.519–1.008 | 0.056 | 0.682 | 0.494–0.942 | 0.020 | 0.836 | 0.607–1.150 | 0.271 | 0.792 | 0.581–1.079 | 0.139 |
| ASDAS, per score | 0.492 | 0.179–1.354 | 0.170 | NA | NA | NA | 0.526 | 0.194–1.429 | 0.208 | NA | NA | NA |
| BASFI, per score | 3.837 | 2.263–6.506 | 0.000 | 3.800 | 2.250–6.417 | 0.000 | 3.092 | 1.896–5.044 | 0.000 | 3.034 | 1.870–4.922 | 0.000 |
| Ever use of biologic DMARDs, vs never | ||||||||||||
| ≥ 12 months | 1.051 | 0.308–3.581 | 0.937 | 1.144 | 0.337–3.885 | 0.829 | 1.425 | 0.417–4.872 | 0.572 | 1.414 | 0.421–4.754 | 0.575 |
| ≤ 12 months | 0.961 | 0.333–2.778 | 0.942 | 1.098 | 0.385–3.132 | 0.861 | 0.971 | 0.329–2.866 | 0.958 | 1.020 | 0.357–2.916 | 0.971 |
| ≤ 6 months | 1.999 | 0.806–4.962 | 0.135 | 1.830 | 0.745–4.495 | 0.188 | 2.461 | 0.976–6.204 | 0.056 | 2.128 | 0.869–5.211 | 0.099 |
| Never | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| MSU crystallization positive, vs negative | ||||||||||||
| Left sacroiliac joint | 0.895 | 0.391–2.049 | 0.794 | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| Right sacroiliac joint | NA | NA | NA | NA | NA | NA | 1.291 | 0.542–3.075 | 0.565 | NA | NA | NA |
| Volume of MSU crystallization, per cm3 | ||||||||||||
| Left sacroiliac joint | 2.018 | 1.144–3.560 | 0.015 | 1.920 | 1.209–3.049 | 0.006 | NA | NA | NA | NA | NA | NA |
| Right sacroiliac joint | NA | NA | NA | NA | NA | NA | 1.387 | 1.022–1.882 | 0.036 | 1.418 | 1.075–1.870 | 0.014 |
Complex model 1 and 3, variables with p < 0.05 in bivariate analysis were included based on the radiographic grade at each sacroiliac joint; simplified model 2 and 4, the models with the repeated variables of the ASDAS score and MSU crystals deposits positive were excluded
AxSpA axial spondyloarthritis, ESR erythrocyte sedimentation rate, CRP C-reactive protein, PGA patient’s global assessment, ASDAS Ankylosing Spondylitis Disease Activity Score, BASFI Bath Ankylosing Spondylitis Functional Index, DMARDs disease-modifying anti-rheumatic drugs, MSU monosodium urate, AOR adjusted odds ratios, 95% CI 95% confidence interval, NA not available
#Including clinical variables and the DECT scans results