Anorexia in Hemodialysis Patients: The Possible Role of Des-Acyl Ghrelin

Abstract

Background: Anorexia is frequently found in end-stage renal disease and is a reliable predictor of morbidity and mortality in hemodialysis (HD) patients. The pathogenesis of anorexia is complex and the appetite-modulating hormone ghrelin could be involved. Two forms of circulating ghrelin have been described: acylated ghrelin (<10% of circulating ghrelin) which promotes food intake, and des-acyl ghrelin which induces a negative energy balance. The aim of this cross-sectional study is to clarify whether anorexia and body weight change in HD patients relate to plasma des-acyl ghrelin levels. Methods: 34 HD patients and 15 healthy controls were studied. The presence of anorexia was assessed by a questionnaire. Serum des-acyl ghrelin was measured in HD patients and in 15 body mass index-, sex- and age-matched controls by ELISA. Energy intake was assessed by a 3-day dietary diary, and fat-free mass (FFM) was evaluated by body impedance analysis. Data have been statistically analyzed and are presented as mean ± SD. Results: 14 patients (41%) were found to be anorexic, and 20 patients (59%) non-anorexic. Energy intake (kcal/day) was significantly lower in anorexic than in non-anorexic patients (1,682 ± 241 vs. 1,972.50 ± 490; p < 0.05). FFM (%) was lower in anorexic than in non-anorexic patients (65.8 ± 4.4 vs. 70.9 ± 8.7; p = 0.05). Plasma des-acyl ghrelin levels (fmol/ml) were significantly higher in HD patients than in controls (214.88 ± 154.24 vs. 128.93 ± 51.07; p < 0.05), and in anorexic HD patients than in non-anorexic (301.7 ± 162.4 vs. 159.1 ± 115.5; p < 0.01). Conclusion: Anorexia is highly prevalent among HD patients and des-acyl ghrelin could be involved in its pathogenesis.