Table 2.

Comparison of serum concentrations of bone biomarkers between healthy controls and RA patients and changes of those over 6 months in the RA patients

	HC	RA
		Baseline	p-value vs. HCa	3 months	p-value vs. baselineb	6 months	p-value vs. baselineb
Dkk-1, pg/ml	4362 (2866–5026)	3340 (2573–4243)	0.25	3260 (2519–4282)	0.86	3242 (2689–4251)	0.98
SOST, pg/ml	2509 (1939–3315)	2616 (1983–3279)	0.64	2588 (2171–3506)	0.68	2738 (2127–3465)	0.62
OC, pg/ml	28,492(18700–35,923)	17,109 (11075–35,817)	0.099	18,271 (12754–31,724)	0.52	21,533 (14559–28,715)	0.26
OPG, pg/ml	1036 (896–1184)	951 (768–1387)	0.76	1082 (903–1469)	0.085	1181 (903–1469)	0.016
OPN, pg/ml	9053 (6282–14,337)	22,928 (17305–37,566)	< 0.0001	23,689 (13849–32,156)	0.76	21,818 (13895–33,550)	0.85

The data are median (interquartile range, Q_1–4–Q_3/4) or number (percentage)

^aComparisons of the serum concentration of bone biomarkers between HC and RA were analyzed using the Mann-Whitney U-test

^b The changes in the serum concentration of bone biomarkers from baseline were analyzed using the Wilcoxon signed ranks test. HC Healthy control, PD Power Doppler, RA Rheumatoid arthritis