Mechanisms of uremic suppression of appetite
Food intake is regulated by short-term satiety factors (gastric distension, amino acids, peptide hormones), as well as factors involved in long-term appetite regulation (leptin, insulin). Integration of the various signals takes place in the central nervous system (CNS). Appetite suppression in uremia is multifactorial and may include effects of uremia per se and of various comorbidity and psychosocial factors. Uremic anorexia is associated with elevated levels in plasma and CNS of short-term satiety factors (cholecystokinine, glucagon, serotonin, middle molecules) and factors that influence long-range regulation of appetite (leptin, insulin), but it is still unsettled to what extent these factors cause or contribute to appetite loss in uremic patients. Proinflammatory cytokines most probably also have a role in appetite suppression and malnutrition in patients with chronic renal failure.