Changes of Plasma Free Choline and Choline-containing Compounds' Concentrations and Choline Loss During Hemodialysis in ESRD Patients

Objectives: This study was undertaken to determine the changes in plasma free choline and choline-containing compounds in end stage renal disease (ESRD) and to determine if they were lost into the dialysate during hemodialysis.

Design And Methods: Plasma and dialysate free choline, phosphocholine and phospholipid-, phosphatidylcholine-, sphingomyelin-bound choline were measured before, during and after hemodialysis.

Results: Plasma free and bound choline concentrations (mean +/- standard error of the mean) were 12.9 +/- 0.6 and 2697 +/- 57 microM or 37.3 +/- 0.9 and 2792 +/- 98 microM in controls or in ESRD patients, respectively. Free choline concentrations were correlated (r = 0.598; p < 0.001) with the time the patients were subjected to hemodialysis. Plasma free choline and phosphocholine concentrations are decreased by a total of -8.1 +/- 0.6 micromol/L and -88 +/- 8 micromol/L, respectively; phospholipid-, phosphatidylcholine- and sphingomyelin-bound choline are increased, during hemodialysis. Patients lost about 350 micromoles of choline into the dialysate during hemodialysis.

Conclusion: Plasma free choline concentrations are elevated in ESRD, and a considerable amount of choline is lost into the hemodialysate.