Table 1

Characteristics of the study population at time of serum sampling
AS (n = 76) IBD-AS (n = 77) P-value
Age, y 39.5 (28.5 to 50.5) 39.0 (31.0 to 50.0) ns
Disease duration, y 5.0 (1.0 to 11.8) 6.0 (1.5 to 11.5) ns
Male, % 86 78 ns
HLA-B27 positive, % 82 59 0.0033
BASDAI, NRS, 0 to 10 4.2 (2.5 to 6.8) 3.3 (2.4 to 6.7) ns
BASFI, NRS, 0 to 10) 4.1 (1.4 to 6.4) 3.2 (0.7 to 6.1) ns
Biologic current, % 24 30 ns
DMARD current, % 11 35 0.0004
Steroid current, % 3 14 0.0173
NSAID current, % 63 39 0.0036
History of uveitis, % 21 31 ns
History of psoriasis, % 7 7 ns
Current smoker, % 28 30 ns
ESR, mm/h 15.7 (3.0 to 25.2) 15.3 (5.3 to 22.5) ns
CRP, mg/L 6.5 (3.0 to 15.5) 9.0 (3.0 to 19.0) 0.0532

Values are median (IQR) unless stated otherwise. For comparison: mechanical back pain patients (n=48): age 43.0 (34.8 to 53.0) y, 56.3% male, ESR 4.0 (2.0 to 7.5) mm/h, CRP 3.0 (3.0 to 3.0) mg/L. HLA, human leukocyte antigen; BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; BASFI, Bath Ankylosing Spondylitis Functional Index; NRS, numerical rating scale; DMARD, disease modifying anti-rheumatic drug; NSAID, non-steroidal anti-inflammatory drug; CRP, C-reactive protein; ESR, erythrocyte sedimentation rate; ns, not significant.

Wallis et al.

Wallis et al. Arthritis Research & Therapy 2013 15:R166   doi:10.1186/ar4350

Open Data