Table 2.

Baseline characteristics: activity and metrology

Characteristic	SpA	nr-axSpA	AS	M-W/FET p value
ASDAS-CRP, median (IQR)	2.2 (1.4–2.8)	2.0 (1.1–2.3)	2.4 (1.7–2.8)	0.022
BASDAI, median (IQR)	2.6 (1.2–4.7)	2.7 (1.0–4.9)	2.4 (1.2–3.7)	0.362
CRP (mg/L)	4.3 (1.2–12.0)	2.5 (0.8–8.2)	7.1 (2.6–14.9)	<0.001
ESR (mm/h)	8.0 (4.0–17.8)	7.0 (3.0–16.0)	12.0 (4.4–22.0)	0.007
BASFI, median (IQR)	1.4 (0.5–2.1)	1.1 (0.3–2.9)	1.8 (0.7–3.3)	0.030
Metrology
Modified Schober (cm), median (IQR)	4.0 (3.0–5.0)	4.5 (3.5–5.5)	4.0 (3.0–5.0)	<0.001
Occiput to wall (cm), median (IQR)	0.0 (0.0–0.0)	0.0 (0.0–0.0)	0.0 (0.0–0.0)	<0.001
Chin–chest distance (cm), median (IQR)	1.5 (0.0–3.0)	1.0 (0.0–2.0)	2.0 (0.0–3.0)	0.008
Chest expansion (cm), median (IQR)	4.0 (3.0–6.0)	4.0 (3.0–6.0)	3.8 (2.0–6.0)	0.136

AS, ankylosing spondylitis; ASDAS-CRP, Ankylosing Spondylitis Disease Activity Score based on CRP; BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; BASFI, Bath Ankylosing Spondylitis Functional Index; CRP, C-reactive protein; ESR, erythrocyte sedimentation rate; M-W/FETp, Mann-Whitney/Fisher exact test p value; nr-axSpA, non-radiographic axial spondyloarthritis; SpA, spondyloarthritis.