Table 1

Baseline characteristics of the patients and controls*

AS patients no inflammation N=6AS patients acute N=9AS patients chronic N=15CD patients N=15Controls N=10
Age, mean (range) years32 (22–45)31 (20–50)33 (20–53)38 (18–51)60 (35–70)
Sex, no. (%) male5 (83)7 (78)13 (87)9 (60)7 (70)
HLA-B27, no. (%)6 (100)9 (100)15 (100)1 (6)
Disease duration, mean (range) months26 (18–36)28 (11–40)20 (8–38)15 (4–46)NA
CRP (mg/l), mean (range)1 (0.5–2)1.2 (0.5–3)1.9 (0.5–3)6.5 (2–13)*NA
Axial involvement, no. (%)6 (100)9 (100)15 (100)1NA
Peripheral arthritis, no. (%)3 (33)4 (27)NA
Enthesitis/dactylitis, no. (%)1 (16)2 (22)2 (13)NA
Uveitis, no. (%)2 (13)NA
Concomitant medical treatment, no. (%)
 NSAIDs3 (50)5 (55)9 (60)NA
 Biological agentsNA
 ImmunosuppressantsNA
BASDAI score, mean (range)†5.45 (4.2–8)6 (4.4–9)6.33 (5–9)NANA
CDAI score, mean (range)‡234 (170–334)
  • *p<0.0001.

  • †Scores for the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) range from 0 to 10, with higher scores indicating more severe disease.

  • †Scores for the CDAI range from 150 to 450, with higher scores indicating more severe disease.

  • AS, ankylosing spondylitis; CD, Crohn's disease; CDAI, CD Activity Index; CRP, C reactive protein; NA, not applicable; NSAIDs, non-steroidal anti-inflammatory drugs.