IL4 and generalized anxiety disorder: Lower levels of IL-10 and higher ratios of TNF-α/IL10, TNF-α/IL4, IFN-γ/IL10 and IFN-γ/IL4 were observed in the serum of GAD patients, showing significantly increased pro- to anti-inflammatory cytokine ratios, which suggests a distinct cytokine imbalance [143] (Table 2).