TNF and rheumatoid arthritis: Regarding the changes in serum cytokine levels, TNF-α levels significantly declined in patients with RA receiving any of the following medications for 6 months: TNF-α inhibitor, IL-6R inhibitor, or csDMARDs alone (median 165.8 pg/ml, IQR 132.8–265.4 pg/ml vs. 78.5 pg/ml, IQR 38.8–136.0 pg/ml, p < 0.01; 175.2 pg/ml, IQR 114.0–324.3 pg/ml vs. 119.2 pg/ml, IQR 39.7–168.6 pg/ml, p < 0.001; 183.6 pg/ml, IQR 90.9–276.3 pg/ml vs. 36.1 pg/ml, IQR 25.2–93.1, p < 0.05).