CCN1 and rheumatoid arthritis: Surprisingly, we found that serum Cyr61 concentration in RA patients with remission/low disease activity was significantly higher than in RA patients with moderate/high disease activity (median [IQR] 226.85 [152.50–339.96] vs. 189.92 [129.58–254.47], P = 0.004) (Table 1 and Fig. 1a).