IL6 and rheumatoid arthritis: IL-6 was higher at baseline in the RA group (median, 9.70 pg/ml; IQR, 7.9–71.95 pg/ml) than in the OA group (median, 2.60 pg/ml; IQR, 2.0–2.70 pg/ml; P < 0.001) or the healthy controls (median, 2.00 pg/ml; IQR, 2.0–2.38 pg/ml; P < 0.001).