first reported the association of cytokine polymorphisms with PSD, showing that patients with polymorphisms of anti-inflammatory cytokines IL-4 and IL-10 rather than pro-inflammatory cytokines TNF-α, IL-1β, IL-6 and IL-8 had an increased propensity to develop depression in the acute phase of stroke (28). This evidence concerns the gene CXCL8 and depressive disorder.