Table 1

Patients’ characteristics

HCSpARA
Number505151
Age (years)*45.6 (±13.3)40.7 (±12.9)†52.3 (±18.2)‡, §
Female, n (%)33 (66)12 (23.5)†37 (72.5)‡
Disease duration (years)*n.a.6.2 (±6.2)4.9 (±5.3)
Disease activity scores
 AS, n (%)n.d.32 (62.7)n.d.
 Psoriasis, n (%)n.d.1 (2)n.d.
 IBD, n (%)n.d.6 (11.8)n.d.
 Uveitis, n (%)n.d.10 (19.6)n.d.
 Peripheral arthritis, n (%)n.d.13 (25.5)n.d.
Disease activity scores
 BASDAI*n.d.3.5 (±2.1)n.d.
 BASFI*n.d.3.4 (±2.9)n.d.
 BASMI*n.d.2.5 (0–7)n.d.
 SDAI*n.d.n.d.15.2 (±12.6)
 DAS28*n.d.n.d.3.3 (±1.7)
Laboratory data
 ESR (mm/1st hour) ¶n.d.13 (2–86)16 (1–113)
 CRP (mg/L) ¶n.d.5 (0–56)3.7 (0–58)
 HLA-B27+, n (%)n.d.43 (84.3)n.d.
 αCCP positive, n (%)n.d.n.d.34 (66.7)
 RF positive, n (%)n.d.n.d.25 (49)
Current medication
 Corticosteroids, n (%)009 (17.6)‡
 Biologicals, n (%)
  anti-TNFα026 (51)13 (25.5)‡
  Tocilizumab004 (7.8)
  Abatacept003 (5.9)
 DMARDs, n (%)
  Methotraxate05 (9.8)30 (58.8)‡
  Leflunomide01 (2)9 (17.6)‡
  Sulfasalazine01 (2)2 (3.9)
  Other004 (7.8)
 NSAIDs, n (%)
  Regularly018 (35.3)9 (17.6)
  On demand023 (45.1)33 (64.7)

  • *Mean (±SD).

  • †p<0.05, aSpA compared with HC.

  • ‡p<0.05, RA compared with aSpA.

  • §p<0.05, RA compared with HC (p values not adjusted for multiple testing).

  • ¶Median (range).

  • AS, ankylosing spondylitis; aSpA, axial spondyloarthritis; BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; BASFI, Bath Ankylosing Spondylitis Functional Index; BASMI, Bath Ankylosing Spondylitis Metrology Index; αCCP, anticyclic citrullinated peptide antibodies; CRP, C-reactive protein (0–5 mg/L); DAS28, Disease Activity Score 28; DMARD, disease-modifying antirheumatic drugs; ESR, erythrocyte sedimentation rate (0–30 mm/h); HCs, healthy controls; HLA, human leucocyte antigen; IBD, inflammatory bowel disease; n, number; n.a., not applicable; n.d., dot determined; NSAID, non-steroidal anti-inflammatory drugs; RA, rheumatoid arthritis; RF, rheumatoid factor; SDAI, simplified disease activity index; -, not applicable.