Commonly, PDN and OSA lead to a deprived glycemic control and OSA is associated with a lack of aerobic capacity due to alterations of the sympathetic nervous system activity, hypothalamic-pituitary-adrenal axis, and formation of reactive oxygen species that lead to an increase of inflammatory cytokines, tumor necrosis factor, and adipocyte-derived factors [40, 41]. Here, TNF is linked to obstructive sleep apnea syndrome.