Table 1.

Baseline Characteristics

Mean ± SD or n (%)ASDAS IDASAS PR
RespondersNon-respondersRespondersNon-responders
(n=211)(n=389)(n=133)(n=470)
Age, y33.6±9.738.9±11.431.8±8.738.5±11.2
Diagnosis duration, y1.7±2.91.8±3.61.7±2.91.7±3.2
Symptom duration, y6.1±6.28.2±8.15.3±5.78.0±7.8
HLA-B27 positive183 (87)274 (70)119 (89)340 (72)
ASDAS3.4±0.83.7±0.83.7±0.93.6±0.8
Inflammation*6.9±1.87.0±2.06.9±1.97.0±1.9
Patient global assessment of pain7.0±1.77.7±1.57.1±1.97.5±1.6
hs-CRP9.0±13.110.9±16.815.5±21.38.8±13.1
BASFI4.6±2.25.7±2.24.9±2.45.4±2.2
HAQ-S1.9±0.52.2±0.51.9±0.62.1±0.5
MRI SI joints positive165 (78)262 (67)102 (77)328 (70)
MRI spine positive59 (28)114 (29)47 (35)126 (27)
  • BASFI, Bath Ankylosing Spondylitis Functional Index; HAQ-S, Health Assessment Questionnaire modified for the Spondyloarthropathies. *Mean of Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) questions 5 and 6 (scale, 0–10).