Table 3.
Association between covariates and the rate of mSASSS progression in the regression models.
| Variable | Univariate analysis |
Multivariable analysis* |
||||
|---|---|---|---|---|---|---|
| Model 1 |
Model 2 |
|||||
| β (95% CI) | p-value | β (95% CI) | p-value | β (95% CI) | p-value | |
| Sex (female) | −0.290 (−0.586, 0.006) | 0.055 | −0.449 (−0.782, −0.117) | 0.008 | −0.440 (−0.775, −0.105) | 0.010 |
| Age | 0.022 (0.010, 0.034) | <0.001 | 0.012 (−0.001, 0.026) | 0.061 | 0.012 (−0.001, 0.025) | 0.076 |
| Eye involvement | 0.623 (0.298, 0.948) | <0.001 | 0.572 (0.264, 0.880) | <0.001 | 0.577 (0.268, 0.886) | <0.001 |
| Peripheral joint involvement | −0.540 (−0.857, −0.223) | 0.001 | −0.508 (−0.810, −0.206) | 0.001 | −0.513 (−0.817, −0.210) | 0.001 |
| HLA-B27 positivity | 0.065 (−0.415, 0.546) | 0.790 | − | − | − | − |
| ESR at the interval start (log) | 0.195 (0.107, 0.283) | <0.001 | 0.176 (0.087, 0.265) | <0.001 | 0.178 (0.088, 0.268) | <0.001 |
| CRP at the interval start (log)† | 0.285 (0.097, 0.472) | 0.003 | − | − | − | − |
| BASDAI at the interval start (square-root) | −0.039 (−0.455, 0.378) | 0.856 | − | − | − | − |
| NSAIDs | 0.004 (−0.195, 0.204) | 0.966 | − | − | − | − |
| Glucocorticoids | 0.097 (−0.231, 0.425) | 0.561 | − | − | − | − |
| cDMARDs | −0.078 (−0.290, 0.135) | 0.474 | −0.081 (−0.276, 0.115) | 0.418 | − | − |
| Sulfasalazine | − | − | − | − | −0.011 (−0.211, 0.189) | 0.913 |
| Methotrexate | − | − | − | − | −0.180 (−0.439, 0.078) | 0.172 |
*
Variables that were significant in univariate analysis at p-value ⩽ 0.1 were included.
†
Excluded from multivariable analysis due to its well-known high correlation with ESR.
BASDAI, Bath Ankylosing Spondylitis Activity Index; cDMARDs, conventional disease-modifying antirheumatic drugs; CI, confidence interval; HLA, human leukocyte antigen; CRP, C-reactive protein; ESR, erythrocyte sedimentation rate; mSASSS, modified Stoke Ankylosing Spondylitis Spine Score; NSAIDs, non-steroidal anti-inflammatory drugs.