title: Effects of Dietary Sodium Restriction in Kidney Transplant Recipients Treated With Renin-Angiotensin-Aldosterone System Blockade: A Randomized Clinical Trial.
abstract: BACKGROUND
  In patients with chronic kidney disease receiving renin-angiotensin-aldosterone system (RAAS) blockade, dietary sodium restriction is an often-used treatment strategy to reduce blood pressure (BP) and albuminuria. Whether these effects extend to kidney transplant recipients is unknown. We therefore studied the effects of dietary sodium restriction on BP and urinary albumin excretion (UAE) in kidney transplant recipients receiving RAAS blockade.
  
  
  METHODS
  Two-center randomized crossover trial.
  
  
  METHODS
  Stable outpatient kidney transplant recipients with creatinine clearance > 30mL/min, BP ≥120/80mmHg, receiving stable RAAS blockade therapy.
  
  
  METHODS
  6-week regular-sodium diet (target, 150mmol/24 h) and a 6-week low-sodium diet (target, 50mmol/24 h).
  
  
  METHODS
  Main outcome parameters were systolic and diastolic BP, UAE, and estimated glomerular filtration rate (eGFR) at the end of each diet period. Dietary adherence was assessed by 24-hour urinary sodium excretion.
  
  
  RESULTS
  We randomly assigned 23 kidney transplant recipients, of whom 22 (mean age, 58±8 [SD] years; 50% men; mean eGFR, 51±21mL/min/1.73m(2)) completed the study. One patient withdrew from the study because of concerns regarding orthostatic hypotension on the low-sodium diet. Sodium excretion decreased from 164±50mmol/24 h during the regular-sodium diet to 87±55mmol/24 h during the low-sodium diet (mean difference, -77 [95% CI, -110 to -44] mmol/24 h; P<0.001). Sodium restriction significantly reduced systolic BP from 140±14 to 129±12mmHg (mean difference, -11 [95% CI, -14 to -7] mmHg; P<0.001), diastolic BP from 86±8 to 79±8mmHg (mean difference, -7 [95% CI, -10 to -5] mmHg; P<0.001). We found no significant effect on natural log (ln)-transformed UAE (mean difference, -0.03 [95% CI, -0.6 to 0.6] ln(mg/24 h); P=0.9) or eGFR.
  
  
  CONCLUSIONS
  No hard end points; small study; small proportion of patients willing to test the intervention; adherence to sodium diet was achieved in 86% of patients.
  
  
  CONCLUSIONS
  In stable kidney transplant recipients receiving RAAS blockade, dietary sodium restriction effectively reduces BP without affecting eGFR. Dietary sodium restriction is relevant to BP management in kidney transplant recipients receiving RAAS blockade.
authors.affiliation: Department of Internal Medicine, Division of Nephrology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands. Electronic address: l.v.de.vries@umcg.nl.
authors.forename: Laura V
authors.initials: LV
authors.lastname: de Vries
authors.affiliation: Renal Transplant Unit, Academic Medical Center Amsterdam, University of Amsterdam, Amsterdam, the Netherlands.
authors.forename: Linn C
authors.initials: LC
authors.lastname: Dobrowolski
authors.affiliation: Department of Internal Medicine, Division of Nephrology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands.
authors.forename: Jacqueline J O N
authors.initials: JJ
authors.lastname: van den Bosch
authors.affiliation: Department of Internal Medicine, Division of Nephrology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands.
authors.forename: Ineke J
authors.initials: IJ
authors.lastname: Riphagen
authors.affiliation: Renal Transplant Unit, Academic Medical Center Amsterdam, University of Amsterdam, Amsterdam, the Netherlands.
authors.forename: C T Paul
authors.initials: CT
authors.lastname: Krediet
authors.affiliation: Renal Transplant Unit, Academic Medical Center Amsterdam, University of Amsterdam, Amsterdam, the Netherlands.
authors.forename: Frederike J
authors.initials: FJ
authors.lastname: Bemelman
authors.affiliation: Department of Internal Medicine, Division of Nephrology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands.
authors.forename: Stephan J L
authors.initials: SJ
authors.lastname: Bakker
authors.affiliation: Department of Internal Medicine, Division of Nephrology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands.
authors.forename: Gerjan
authors.initials: G
authors.lastname: Navis
mesh_terms: D000419:Albuminuria / Q000652:urine*; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use*; D001794:Blood Pressure; D018592:Cross-Over Studies; D004039:Diet, Sodium-Restricted; D005260:Female; D006801:Humans; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors
keywords: Kidney transplantation; RAAS blockade; albuminuria; antihypertensive treatment; antiproteinuric treatment; blood pressure; clinical trial; cross-over trial; diet; dietary sodium restriction; hypertension; lifestyle intervention; randomized trial; renal transplant recipients; renin-angiotensin-aldosterone system (RAAS); urinary albumin excretion