IL6 and major depressive disorder: The changes of electroneurophysiological indexes, tumor necrosis factor‐α (TNF‐α), interleukin‐6 (IL‐6), high sensitivity‐C reactive protein (hs‐CRP), Hamilton depression scale (HAMD) score, and Hamilton anxiety scale (HAMA) score before and after treatment in the two groups were recorded, and the total effective rate of clinical treatment in the two groups was counted.