title: The effect of fluid intake on chronic kidney transplant failure: a pilot study.
abstract: OBJECTIVE
  Transplant recipients are generally instructed to increase their daily fluid intake so as to preserve kidney function. However, studies supporting this hypothesis are lacking.
  
  
  METHODS
  Prospective, randomized study at a tertiary care university hospital.
  
  
  METHODS
  Patients with chronic kidney transplant failure.
  
  
  METHODS
  Assignment to normal fluid intake (NFI: 2 L/day) or high fluid intake (HFI: 4 L/day) for 12 months.
  
  
  METHODS
  The effect of fluid intake on the decrease in estimated glomerular filtration rate (eGFR) was estimated by a mixed-effects general linear model. The analysis was adjusted for the observation period, age, intake of angiotensin-converting enzyme inhibitors or angiotensin II type 1 receptor blockers, diuretics, and transplant duration.
  
  
  RESULTS
  A total of 33 patients were randomized to NFI and 29 to HFI. After 12 months, the mean eGFR had decreased to a similar extent in both groups (NFI: 44 ± 9 mL/min vs. 41 ± 9 mL/min; HFI: 46 ± 15 mL/min vs. 44 ± 15 mL/min). In the multivariate analysis, only the observation period had a significant effect on the decrease in eGFR. Randomization to NFI or HFI nor any other variable was associated with kidney function. The association between urine volume and urine osmolality was lost after 12 months.
  
  
  CONCLUSIONS
  Recommendation of higher fluid intake does not seem to improve chronic kidney transplant failure. However, the lack of association between urine osmolality and reported urine volume at a later stage implies a loss of adherence to fluid intake over time.
authors.affiliation: Division of Nephrology and Dialysis, Department of Internal Medicine III, Medical University Vienna, Austria.
authors.forename: Laurene
authors.initials: L
authors.lastname: Magpantay
authors.forename: Farzad
authors.initials: F
authors.lastname: Ziai
authors.forename: Rainer
authors.initials: R
authors.lastname: Oberbauer
authors.forename: Martin
authors.initials: M
authors.lastname: Haas
mesh_terms: D000328:Adult; D000368:Aged; D047228:Angiotensin II Type 1 Receptor Blockers / Q000008:administration & dosage; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000008:administration & dosage; D002908:Chronic Disease; D018450:Disease Progression; D004232:Diuretics / Q000008:administration & dosage; D004326:Drinking; D005260:Female; D005440:Fluid Therapy / Q000379:methods*; D005919:Glomerular Filtration Rate / Q000187:drug effects; D006084:Graft Rejection / Q000628:therapy*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000503:physiopathology* / Q000628:therapy*; D016030:Kidney Transplantation / Q000009:adverse effects*; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010865:Pilot Projects; D011446:Prospective Studies
chemical_list: D047228:Angiotensin II Type 1 Receptor Blockers; D000806:Angiotensin-Converting Enzyme Inhibitors; D004232:Diuretics