. Author manuscript; available in PMC: 2016 Nov 1.

Published in final edited form as: Arthritis Rheumatol. 2015 Nov;67(11):2905–2915. doi: 10.1002/art.39279

Table 1.

Association of PBL transcriptome IL-1β, TNFα and COX-2 (relative gene expression levels were dichotomized by median), with joint space narrowing (JSN) at 24 months in 109 patients with symptomatic knee osteoarthritis in the medial compartment for whom gene expression data were available.

	IL-1β (PBL mRNA)			TNFα (PBL mRNA)			COX-2 (PBL mRNA)
	OA^IL-1 (n=54)	OA^nl (n=55)	p value	OA^TNFα (n=54)	OA^nl (n=55)	p value	OA^COX-2 (n=54)	OA^nl (n=55)	p value
Baseline Medial knee JSW (mm)	3.85 (1.39)	3.46 (1.29)	0.131	3.60 (1.28)	3.70 (1.45)	0.706	3.76 (1.43)	3.55 (1.27)	0.418
24 month Medial knee JSW (mm)	3.14 (1.58)	3.12 (1.49)	0.933	2.85 (1.58)	3.41 (1.43)	0.057	3.05 (1.57)	3.21 (1.49)	0.571
JSN (mm)	0.71 (0.93)	0.34 (0.82)	0.032	0.75 (1.03)	0.30 (0.67)	0.007	0.71 (0.90)	0.34 (0.86)	0.027

Biomarkers were dichotomized based on median levels to define two groups of subjects (e.g., with biomarker above vs. at or below the threshold); mean JSN values were compared in the two subject groups using a two-sample t-test. Of the 111 completers, gene expression data were available for 109 subjects.