Peritoneal transport characteristics and dwelling time significantly impact ghrelin clearance in peritoneal dialysis patients.

Background: Plasma ghrelin exerts widespread bioactivities. Although it is effectively removed from the blood by a single course of haemodialysis, peritoneal clearance of ghrelin is uncertain. Our study aimed to determine (i) whether there is a correlation between plasma ghrelin levels and characteristics of peritoneal ghrelin clearance, and (ii) whether plasma ghrelin levels significantly impact markers of mortality or morbidity in continuous ambulatory peritoneal dialysis (CAPD) patients.

Methods: We enrolled 50 qualified CAPD patients. Blood was drawn during the fasting state and 2 h post-prandially. Also during these periods, peritoneal effluents were collected for radioimmunoassay of total plasma ghrelin level and measurement of other parameters. Twenty-four hour ascites were collected for determination of ghrelin daily mass transfer.

Results: Peritoneal ghrelin clearance was positively correlated with the dialysate-peritoneal creatinine (D/P(Cr)) ratio. Fasting plasma ghrelin levels were inversely correlated with the peritoneal/plasma (D/P(ghrelin)) ratio (P = 0.045). Plasma ghrelin levels were negatively correlated with body mass index, waist-hip ratio, fasting insulin and triglyceride level, and positively correlated with lean body mass. Plasma ghrelin levels were positively correlated with left ventricular mass (LVM), left ventricular mass index and blood pressure.

Conclusions: Peritoneal transporter characteristics may modulate plasma ghrelin levels in CAPD subjects. By contributing to the level of plasma ghrelin, dwelling time may have an impact on LVM and associated morbidity in CAPD patients.