Baseline predisposing factors of a maintained (no change) diagnosis of axSpA during the 10-year follow-up period (results of the multivariate analysis on the imputed datasets)
| Baseline characteristics | Change in the diagnosis during the 10-year period | OR (95% CI) | |
| Yes* | No* | ||
| 14.8 (14.5–14.8) | 85.2 (85.2–85.5) | ||
| X-rays SIJ† structural damage | 4.8 (3.8–4.8) | 30.5 (30.3–31.1) | 16.97 (4.06 to 71.02) |
| Psoriasis (past or present) | 4.8 (3.9–4.9) | 18.9 (18.8–19) | 5.33 (1.99 to 14.27) |
| CRP≥6 mg/L | 11 (10.1–11.1) | 33 (32.9–33.1) | 2.65 (1.33 to 5.88) |
| Good NSAID response | 62.9 (62.1–63.1) | 83.0 (82.8–83.1) | 2.50 (1.51 to 4.15) |
| HLA B27 positive | 40.0 (39.0–40.8) | 61.2 (61–61.2) | 2.04 (1.27 to 3.27) |
| Anterior chest wall pain | 31.4 (30.8–31.4) | 46.9 (46.9–47) | 2.02 (1.23 to 3.32) |
| Female | 46.7 (46.2–47.6) | 55.1 (54.9–55.1) | 1.88 (1.17 to 3.01) |
*Data provided are the observed median, minimal and maximal percentage values from the imputed datasets.
†X-rays SIJ structural damage=presence of structural damage suggestive of axSpA on pelvic X-rays based on the local reader (either radiologist or rheumatologist).