Depressive symptoms may not only increase the secretion of pro-inflammatory cytokines [40,41], such as interleukin-6 and high sensitive c-reactive protein [71], relating to microglial activation, blood–brain barrier dysfunction, and subsequent neuronal damage [72], but also decrease the release of neurotrophic factors [73], maintaining neuronal health and regulating synaptic plasticity, which in combination could lead to cognitive impairment [74]. This evidence concerns the gene IL6 and Cognitive impairment.