Calprotectin (S100A8/A9) has the strongest association with ultrasound-detected synovitis and predicts response to biologic treatment: results from a longitudinal study of patients with established rheumatoid arthritis

Table 2 Spearman’s rank correlation coefficients between biomarkers and ultrasound sum scores and clinical parameters at baseline

	Sum GS score	Sum PD score	Assessor’s global VAS	DAS28	Swollen joint count (of 32)	Tender joint count (of 32)	Patient’s global VAS	Joint pain VAS
Calprotectin	0.59^a	0.62^a	0.60^a	0.49^a	0.47^a	0.17^b	0.27^a	0.32^a
S100A12	0.39^a	0.42^a	0.44^a	0.35^a	0.35^a	0.14	0.22^b	0.23^b
IL-6	0.42^a	0.49^a	0.53^a	0.39^a	0.41^a	0.09	0.20^b	0.24^b
VEGF	0.20^b	0.18^b	0.14	0.10	0.13	−0.03	0.15	0.21^b
ESR	0.19^b	0.30^a	0.46^a	0.67^a	0.22^b	0.27^a	0.28^a	0.33^a
CRP	0.41^a	0.47^a	0.46^a	0.47^a	0.30^a	0.15	0.18^b	0.24^b

Abbreviations: Sum GS score Sum of greyscale scores on a 0–3 scale of 36 joints and four tendon sheaths, Sum PD score Sum power Doppler scores on a 0–3 scale of 36 joints and 4 tendon sheaths, VAS Visual analogue scale, DAS28 Disease Activity Score in 28 joints (including erythrocyte sedimentation rate), VEGF Vascular endothelial growth factor, IL-6 Interleukin 6, ESR Erythrocyte sedimentation rate, CRP C-reactive protein
^a p < 0.05
^b p ≤ 0.001

ISSN: 1478-6362