Demographics of patients and clinical factors associated with radiographic damage in ankylosing spondylitis (AS)
| Patients with AS (n=444) | Factors associated with final mSASSS*† | |||
| Estimate | SE | P value | ||
| Age at enrolment, years | 31.4 (25.5–37.2) | 0.007 | 0.003 | 4.13×10−2 |
| Male sex | 401 (90.3) | 0.138 | 0.094 | 0.142 |
| Symptom duration at enrolment, years | 8.5 (4.0–14.0) | 0.010 | 0.004 | 1.14×10−2 |
| Follow-up duration, years | 9.6 (7.9–11.3) | 0.038 | 0.009 | 2.14×10−5 |
| HLA-B27 positivity | 427 (96.2) | 0.087 | 0.130 | 0.504 |
| Family history of AS | 30 (6.8) | 0.078 | 0.097 | 0.424 |
| Uveitis | 189 (42.6) | 0.157 | 0.050 | 1.95×10−3 |
| Peripheral joint involvement | 199 (44.8) | −0.246 | 0.054 | 6.85×10−6 |
| Inflammatory bowel disease | 4 (0.9) | 0.164 | 0.258 | 0.526 |
| Psoriasis | 15 (3.4) | −0.016 | 0.135 | 0.903 |
| Ever smoker† | 292 (66.1) | 0.130 | 0.059 | 2.72×10−2 |
| Use of anti-TNF | 277 (62.4) | 0.056 | 0.053 | 0.287 |
| Use of NSAIDs | 439 (98.9) | 0.220 | 0.232 | 0.343 |
| Baseline mSASSS | 7.7 (5.5–16.8) | 0.796 | 0.035 | 3.22×10−75 |
Results are expressed as median (IQR) and n (%).
*Log (mSASSS+1) value was used.
†Smoking data were available for 442 patients.
HLA, human leucocyte antigen; mSASSS, modified stoke ankylosing spondylitis spinal score; NSAIDs, non-steroidal anti-inflammatory drug; TNF, tumour necrosis factor.