title: Effect of oral sodium bicarbonate on fibroblast growth factor-23 in patients with chronic kidney disease: a pilot study.
abstract: The regulation of fibroblast growth factor-23 (FGF23) secretion in patients with chronic kidney disease (CKD) is incompletely understood. An in vitro study showed that metabolic acidosis increased FGF23 in mouse bone. The objective of this study is to evaluate the effect of oral sodium bicarbonate on circulating FGF23 levels in patients with CKD.
  
  
  
  This was a single-blind pilot study. Twenty adults with estimated glomerular filtration rate between 15-45 mL/min/1.73 m(2) and serum bicarbonate between 20-24 mEq/L were treated with placebo for 2 weeks, followed by increasing doses of oral sodium bicarbonate (0.3, 0.6 and 1.0 mEq/kg/day) in 2 week intervals for a total of 6 weeks. C-terminal FGF23 levels were measured at the initial visit, after 2 weeks of placebo and after 6 weeks of bicarbonate therapy. Wilcoxon matched-pairs signed-rank test was used to compare FGF23 before and after sodium bicarbonate.
  
  
  
  After 6 weeks of oral sodium bicarbonate, the median FGF23 increased significantly from 150.9 RU/mL (IQR 107.7-267.43) to 191.4 RU/mL (IQR 132.6-316.9) (p = 0.048) and this persisted after excluding participants who received activated vitamin D.
  
  
  
  FGF23 increased after short-term oral sodium bicarbonate therapy in patients with CKD and mild metabolic acidosis. It is unclear whether this was due to the alkalinizing effect of sodium bicarbonate or other factors.
  
  
  
  The study was registered at ClinicalTrials.gov ( NCT00888290 ) on April 23, 2009.
authors: Department of Medicine, University of Rochester School of Medicine and Dentistry, 601 Elmwood Avenue, Box 675, Rochester, NY, 14642, USA. Wei_chen@urmc.rochester.edu.
authors: Wei
authors: W
authors: Chen
authors: Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, USA.|Department of Epidemiology & Population Health, Albert Einstein College of Medicine, Bronx, NY, USA.
authors: Michal L
authors: ML
authors: Melamed
authors: Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH, USA.
authors: Thomas H
authors: TH
authors: Hostetter
authors: Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, USA.
authors: Carolyn
authors: C
authors: Bauer
authors: Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, USA.
authors: Amanda C
authors: AC
authors: Raff
authors: Department of Biostatistics & Computation Biology, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA.
authors: Anthony L
authors: AL
authors: Almudevar
authors: Department of Biostatistics & Computation Biology, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA.
authors: Amy
authors: A
authors: Lalonde
authors: Department of Biostatistics & Computation Biology, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA.
authors: Susan
authors: S
authors: Messing
authors: Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, USA.|Department of Epidemiology & Population Health, Albert Einstein College of Medicine, Bronx, NY, USA.
authors: Matthew K
authors: MK
authors: Abramowitz
mesh_terms: D000284:Administration, Oral; D000368:Aged; D005260:Female; D000089703:Fibroblast Growth Factor-23; D005346:Fibroblast Growth Factors / Q000097:blood*; D005919:Glomerular Filtration Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D051436:Renal Insufficiency, Chronic / Q000097:blood* / Q000188:drug therapy* / Q000503:physiopathology; D016037:Single-Blind Method; D017693:Sodium Bicarbonate / Q000008:administration & dosage*
chemical_list: C000717427:FGF23 protein, human; C000717428:Fgf23 protein, mouse; D005346:Fibroblast Growth Factors; D000089703:Fibroblast Growth Factor-23; D017693:Sodium Bicarbonate
keywords: Alkali therapy; Fibroblast growth factor-23; Metabolic acidosis; Mineral metabolism; Sodium bicarbonate; Vitamin D