Furthermore, a certain number of studies provided novel evidence that CNS (central nervous system) inflammation involving levels of cytokines such as IL-1β, IL-6 and IL-8 and pro-inflammatory molecules such as interferon gamma (IFN-γ) and anti-inflammatory molecules including insulin-like growth factor 1 (IGF-1) and IL-1ra may be associated with pathogenesis of delirium. This evidence concerns the gene IGF1 and delirium.