title: The metabolic response to ingested protein is normal in long-term hemodialysis patients.
abstract: BACKGROUND
  Protein-energy malnutrition affects 30% to 50% of hemodialysis (HD) patients. This has been attributed to inadequate food intake, but may be caused by disturbances in utilization of ingested protein.
  
  
  METHODS
  We studied protein kinetics during fasting and during ingestion of a protein-enriched meal to investigate possible metabolic differences between stable HD patients and control subjects. Whole-body protein kinetics was measured by means of a primed constant infusion of L[1-13C] valine.
  
  
  RESULTS
  During fasting, whole-body protein balance was significantly less negative in HD patients compared with control subjects. During meal intake, protein balance was similar between HD patients and control subjects. Meal intake increased protein balance significantly in both groups, but not differently between the groups. Also, protein oxidation was decreased during fasting in HD patients compared with control subjects, but not during meal intake.
  
  
  CONCLUSIONS
  We conclude that the rate of protein breakdown is lower in HD patients compared with control subjects, but the efficiency of protein utilization is normal in HD patients during a nondialysis day.
authors.affiliation: Department of Internal Medicine, Division of Nephrology, University Hospital Groningen, Groningen, The Netherlands.
authors.forename: Jorden M
authors.initials: JM
authors.lastname: Veeneman
authors.forename: Hermi A
authors.initials: HA
authors.lastname: Kingma
authors.forename: Theo S
authors.initials: TS
authors.lastname: Boer
authors.forename: Frans
authors.initials: F
authors.lastname: Stellaard
authors.forename: Paul E
authors.initials: PE
authors.lastname: de Jong
authors.forename: Dirk-Jan
authors.initials: DJ
authors.lastname: Reijngoud
authors.forename: Roel M
authors.initials: RM
authors.lastname: Huisman
mesh_terms: D000328:Adult; D001944:Breath Tests; D002247:Carbon Isotopes; D004044:Dietary Proteins / Q000378:metabolism*; D002149:Energy Intake; D004734:Energy Metabolism; D005215:Fasting; D005260:Female; D006801:Humans; D008297:Male; D013058:Mass Spectrometry; D008875:Middle Aged; D006435:Renal Dialysis; D014633:Valine / Q000378:metabolism
chemical_list: D002247:Carbon Isotopes; D004044:Dietary Proteins; D014633:Valine