Multivariable GEE results (adjOR; 95% CI) for the outcome syndesmophyte formation or syndesmophyte formation/growth according to X-ray reader 1 or/and reader 2*
| Variables | Syndesmophyte formation according to X-ray reader 1 or reader 2 | Syndesmophyte formation or growth according to X-ray reader 1 or reader 2 | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| VCI at any time point | 1.98 (1.49, 2.62) | − | − | − | − | 1.84 (1.41, 2.41) | − | − | − | − |
| VCFD at any time point | − | 2.32 (1.85, 2.91) | − | − | − | − | 2.27 (1.83, 2.81) | − | − | − |
| Sequential or simultaneous presence of VCI and VCFD across the 3 time points | − | − | 2.73 (2.00, 3.74) | − | − | − | − | 2.58 (1.91, 3.48) | − | − |
| New VCFD preceded by VCI | − | − | − | 2.45 (1.66, 3.60) | − | − | − | − | 2.12 (1.46, 3.08) | − |
| Absence of VCI or VCFD across the 3 time points | − | − | − | − | 0.45 (0.36, 0.56) | − | − | − | − | 0.47 (0.38, 0.58) |
| Treatment (infliximab) | 1.03 (0.75, 1.41) | 1.09 (0.80, 1.49) | 1.02 (0.74, 1.40) | 1.05 (0.77, 1.44) | 1.04 (0.76, 1.44) | 1.15 (0.85, 1.56) | 1.23 (0.92, 1.67) | 1.18 (0.87, 1.59) | 1.14 (0.84, 1.55) | 1.18 (0.87, 1.60) |
| Gender (male) | 3.30 (1.94, 5.60) | 3.02 (1.79, 5.10) | 3.39 (2.01, 5.74) | 3.36 (1.98, 5.70) | 3.00 (1.77, 5.08) | 3.31 (1.96, 5.62) | 2.94 (1.75, 4.91) | 3.31 (1.96, 5.59) | 3.34 (1.98, 5.61) | 3.01 (1.79, 5.06) |
| Syndesmophyte/ankylosis at baseline | 2.91 (2.00, 4.25) | 2.82 (1.92, 4.13) | 2.95 (2.02, 4.29) | 2.89 (1.98, 4.21) | 2.81 (1.91, 4.11) | 3.43 (2.32, 5.08) | 3.27 (2.20, 4.85) | 3.39 (2.29, 5.01) | 3.48 (2.35, 5.14) | 3.27 (2.20, 4.85) |
| Variables | Syndesmophyte formation according to X-ray reader 1 and reader 2 | Syndesmophyte formation or growth according to X-ray reader 1 and reader 2 | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| VCI at any time point | 1.93 (1.22, 3.05) | − | − | − | − | 1.75 (1.17, 2.61) | − | − | − | − |
| VCFD at any time point | − | 1.60 (1.10, 2.33) | − | − | − | − | 1.85 (1.35, 2.53) | − | − | − |
| Sequential or simultaneous presence of VCI and VCFD across the 3 time points | − | − | 2.29 (1.37, 3.83) | − | − | − | − | 2.12 (1.36, 3.31) | − | − |
| New VCFD preceded by VCI | − | − | − | 3.01 (1.76, 5.13) | − | − | − | − | 2.17 (1.32, 3.56) | − |
| Absence of VCI or VCFD across the 3 time points | − | − | − | − | 0.62 (0.43, 0.89) | − | − | − | − | 0.56 (0.41, 0.76) |
| Treatment (infliximab) | 1.29 (0.68, 2.44) | 1.26 (0.66, 2.39) | 1.28 (0.67, 2.43) | 1.32 (0.70, 2.50) | 1.30 (0.68, 2.49) | 1.15 (0.63, 2.11) | 1.29 (0.72, 2.31) | 1.20 (0.66, 2.18) | 1.08 (0.59, 2.01) | 1.21 (0.66, 2.22) |
| Gender (male) | 2.50 (0.83, 7.51) | 2.36 (0.80, 6.97) | 2.48 (0.85, 7.26) | 2.47 (0.83, 7.33) | 2.29 (0.77, 6.77) | 3.19 (1.03, 9.91) | 2.70 (0.92, 7.88) | 3.12 (1.03, 9.50) | 3.20 (1.05, 9.74) | 2.64 (0.90, 7.80) |
| Syndesmophyte/ankylosis at baseline | 4.11 (1.56, 10.8) | 4.22 (1.58, 11.2) | 4.19 (1.60, 11.0) | 4.14 (1.58, 10.9) | 4.18 (1.56, 11.2) | 5.45 (2.00, 14.9) | 5.65 (2.03, 15.7) | 5.50 (2.02, 15.0) | 5.54 (2.03, 15.1) | 5.53 (1.97, 15.5) |
*Results are shown for a selected set of MRI case-definitions and for the adjustment variables: treatment (forced into the model) and gender and presence of syndesmophytes/ankylosis at baseline (the only two other variables significantly associated with new bone formation in univariable analysis); models also adjusted for within-patient correlation by VU-level and MRI-reader. adjOR, adjusted odds ratio; VCI, vertebral corner inflammation; VCFD, vertebral corner fat deposition.