Plasma Ghrelin level; anorexigenic and orexigenic mediators in patients with end stage renal failure on hemodialysis

ABSTRACT

Anorexia-associated malnutrition is a severe complication that increases mortality in hemodialysis [HD] patients. Ghrelin is a recently-discovered orexigenic hormone with actions in brain and stomach. We analyzed, in 22 HD patients, the possible relationship between ghrelin and appetite regulation with regard to other orexigens [NO3] and anorexigens [cholecystokinin [CCK], leptin, glucose-dependent insulinotropic peptide [GIP]. All orexigens and anorexigens were determined in plasma. Eating motivation was evaluated using a visual analog scale [VAS]. The patients were divided into three groups those with anorexia [n = 8], those with obesity associated with high intake [n = 5], and those with no eating behavior disorders [n = 9]. A control group of 10 healthy volunteers was also evaluated. Mean plasma levels of ghrelin were high [4101 +/- 1233 mg/mL], with the patients showing values above the control group range [1920 +/- 451mg/mL]. Patients with anorexia had lower ghrelin level and higher CCK and GIP levels than did the other patients. Patients with anorexia also had an early satiety score and low desire and pleasure in eating on the VAS and diet survey. We observed significant positive linear correlations between ghrelin and albumin [r = 0.43, p < 0.05], growth hormone [r=0.66, p < 0.01], NO3 [r = 0.36, p < 0.05], and eating motivation [VAS]. At the same time, negative relationships were observed between blood ghrelin and GIP [r = -0.42, p < 0.05], insulin [r = -0.4, p < 0.05], and leptin [r = -0.45, p < 0.05]. Ghrelin levels were not related to levels of CCK. Ghrelin plasma levels are elevated in HD patients. Uremic patients with anorexia show relatively lower ghrelin plasma levels than the levels seen in obese patients or in patients with normal appetite. The role of ghrelin in appetite modulation is altered in uremic HD patients, and that alteration is possibly associated with disorders in insulin and growth hormone metabolism