Table 1.

Disease characteristics of the axial spondyloarthritis (SpA) population.

Variables*AS, n = 639nr-axSpA, n = 73p
Male %76.247.9< 0.0001
HLA-B27 positive, %78.972.50.21
Age at last visit, yrs41.4 (13.6)37.7 (12.7)0.05
Age at time of diagnosis, yrs30.5 (11.7)32.2 (12.0)0.11
Age at symptom onset, yrs23.9 (9.8)26.4 (10.6)0.03
Time from symptom onset to diagnosis, yrs6.7 (7.9)5.5 (6.3)0.28
Disease duration at last clinic visit, yrs17.7 (12.3)12.1 (8.5)0.0002
Currently unemployed due to disability from AS, %15.66.90.05
Current NSAID use, %68.872.20.59
Current DMARD use, %18.418.81.00
Current glucocorticoid use, %5.64.10.79
Ever biologic use, %44.442.50.80
Current biologic use, %43.634.30.16
CRP, mg/l11.4 (14.9)5.2 (5.3)< 0.0001
ESR, mm/h13.7 (14.2)9.9 (11.9)0.02
Total back pain, VAS, 0–104.4 (2.5)4.7 (2.8)0.46
BASDAI4.4 (2.3)4.7 (2.2)0.35
BASMI2.8 (2.5)1.4 (1.2)< 0.0001
BASFI3.6 (2.6)3.0 (2.4)0.05
BAS-G4.8 (2.4)5.2 (2.5)0.29
HAQ-DI0.65 (0.58)0.57 (0.48)0.27
SF-36 mental component46.4 (10.7)45.7 (10.7)0.63
SF-36 physical component38.2 (10.2)37.9 (10.8)0.80
Fatigue severity scale5.1 (2.6)5.2 (2.6)0.68
ASQoL7.4 (5.5)7.1 (5.2)0.60
EQ-5D0.70 (0.21)0.67 (0.19)0.41
History of fibromyalgia, %6.113.70.02
History of uveitis, %29.227.40.79
History of psoriasis, %9.49.60.98
History of IBD, %12.511.00.85
Ever smoker, %43.041.10.81
Current smoker, %23.218.30.37
  • * Values are mean (SD) unless stated otherwise.

  • Statistically significant. NSAID: nonsteroidal antiinflammatory drug; DMARD: disease-modifying antirheumatic drug; VAS: visual analog scale; BASDAI: Bath Ankylosing Spondylitis Disease Activity Index; BASMI: Bath Ankylosing Spondylitis Metrology Index; BASFI: Bath Ankylosing Spondylitis Functional Index; BAS-G: Bath Ankylosing Spondylitis patient Global score; ASQoL: Ankylosing Spondylitis Quality of Life score; EQ-5D: European Quality of Life 5 Dimensions questionnaire; CRP: C-reactive protein; ESR: erythrocyte sedimentation rate; HAQ-DI: Health Assessment Questionnaire–Disability Index; SF-36: Medical Outcomes Study Short Form-36 questionnaire; IBD: inflammatory bowel disease.