| Variables | Responders (n = 40) | Non-responders (n = 13) | p Value |
| Male gender (number, %) | 29 (73) | 11 (85) | 0.38 |
| Age (years) | 41 (11.2) | 41 (8.8) | 0.82 |
| Caucasian (number, %) | 36 (90) | 9 (69) | 0.07 |
| BMI | 25 (4.8) | 24 (3.1) | 0.53 |
| HLA B27+ (number, %) | 34 (90) | 10 (83) | 0.57 |
| Peripheral arthritis (number, %) | 21 (53) | 7 (54) | 0.99 |
| BASDAI | 6.4 (1.3) | 6.2 (1.4) | 0.57 |
| Patient Global Disease Activity (VAS) | 7.1 (1.5) | 7.4 (1.9) | 0.31 |
| BASFI | 6.2 (2.1) | 6.2 (2.2) | 0.86 |
| ESR (median, range) | 22 (1–114) | 22 (1–87) | 0.82 |
| CRP (median, range) | 18 (1–91) | 10 (1–92) | 0.45 |
| Etanercept level (mg/litre) | 2.7 (1.3) | 2.8 (1.1) | 0.50 |
Except where indicated otherwise, the values are the mean (SD).
ASAS, Assessment in Ankylosing Spondylitis; BASDAI, Bath Ankylosing Spondylitis Disease Activity Index (0–10); BASFI, Bath Ankylosing Spondylitis Functional Index (0–10); BMI, body mass index; CRP, C-reactive protein; ESR, erythrocyte sedimentation rate; HLA B27, human leukocyte antigen B27; VAS, visual analogue scale.