Shearer et al. (2001) similarly reported that four nights of total sleep deprivation resulted in significant increases in levels of IL-6 and soluble TNFα receptor I in 21 healthy individuals. These inflammatory processes extend into chronic timescales as well, such that IL-6 and TNFα levels are correlated with severity of self-reported sleep dysfunction in otherwise healthy individuals with chronic insomnia (Ren et al., 2021). Here, IL6 is linked to Sleep disturbance.