Table 2.

Correlations between trabecular bone score (TBS) and bone mineral density (BMD) and disease activity scores and spinal structural damage.

	Baseline, n = 240	Followup, yrs
	Baseline, n = 240	Year 1, n = 131	Year 2, n = 138	Year 3, n = 85	Year 4, n = 57
TBS
BASDAI (0–10)	0.049	−0.118	−0.197^*	0.046	0.205
ASDAS-ESR	−0.088	−0.181^*	−0.233^**	−0.024	0.093
ASDAS-CRP	−0.081	−0.124	−0.314^**	−0.055	−0.015
ESR, mm/h	−0.252^**	−0.217^*	−0.168^*	−0.091	−0.155
CRP, mg/l	−0.177^**	−0.150	−0.284^**	−0.182	−0.212
mSASSS	−0.419^**	−0.365^**	−0.535^**	−0.306^**	−0.412^**
No. syndesmophyte	−0.336^**	−0.249^**	−0.443^**	−0.268^*	−0.336^*
BMD at lumbar spine
BASDAI (0–10)	−0.056	0.113	0.121	0.005	0.232
ASDAS-ESR	−0.150^*	0.032	0.010	−0.020	0.041
ASDAS-CRP	−0.143^*	0.014	0.046	0.081	0.086
ESR, mm/h	−0.316^**	−0.162	−0.168^*	−0.051	−0.071
CRP, mg/l	−0.225^**	−0.105	−0.111	0.091	0.008
mSASSS	0.114	0.187^*	0.245^**	0.241^*	0.344^**
No. syndesmophyte	0.217^**	0.277^**	0.297^**	0.247^*	0.360^**

↵* p-value < 0.05.
↵** p-value < 0.01. BASDAI: Bath Ankylosing Spondylitis Disease Activity Index; ASDAS: Ankylosing Spondylitis Disease Activity Score; ESR: erythrocyte sedimentation rate; CRP: C-reactive protein; mSASSS: modified Stoke Ankylosing Spondylitis Spinal Score.