LEP and mood disorder: To elaborate, the sleeping habits in subjects with CDs are subject to change by the pain caused by some CDs, medications/treatments, and mood disorders.47 On the other hand, it is well known that sustained sleep deprivation induces adverse effects on the cardio-metabolic, endocrine, and immune systems, and inflammatory pathways.48,49 Moreover, shorter sleep durations could modify the circadian rhythm and alter hormonal systems (e.g., insulin resistance and decreased leptin).50