title: Low body mass index and dyslipidemia in dialysis patients linked to elevated plasma fibroblast growth factor 23.
abstract: BACKGROUND
  Fibroblast growth factor 23 (FGF23) has been associated with death in dialysis patients. Since FGF23 shares structural features with FGF19 subfamily members that exert hormonal control of fat mass, we hypothesized that high circulating FGF23 concentrations would be associated with the development of a uremic lipid profile and lower body mass index (BMI).
  
  
  METHODS
  This study was conducted among 654 patients receiving chronic hemodialysis. C-terminal FGF23 concentrations were measured in stored plasma samples. Linear regression was used to examine the cross-sectional associations of plasma FGF23 concentrations with BMI, total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C) and triglycerides. Cox proportional hazard models were used to examine the association between FGF23 concentrations and all-cause mortality.
  
  
  RESULTS
  Participants had a mean age of 60 ± 11 years and a median (IQR) FGF23 concentration of 4,212 (1,411-13,816) RU/ml. An increase per SD in log10 FGF23 was associated with lower BMI (β = -1.11; p = 0.008), TC (β = -6.46; p = 0.02), LDL-C (β = -4.73; p = 0.04) and HDL-C (β = -2.14; p = 0.03); after adjusting for age, gender, race, cardiovascular risk factors, serum albumin, markers of mineral metabolism, and use of lipid-lowering drugs. The association of FGF23 with death was attenuated after adjustment for HDL-C (HR of highest quartile 1.53, 95% CI 1.06-2.20 compared to lowest quartile).
  
  
  CONCLUSIONS
  These results indicate that higher plasma FGF23 levels are associated with lower BMI and dyslipidemia in dialysis patients. The association between FGF23 and death may be mediated through unexplored metabolic risk factors unrelated to mineral metabolism.
authors: Division of Renal Diseases and Hypertension, University of Colorado, Aurora, CO, USA.
authors: John R
authors: JR
authors: Montford
authors: Michel
authors: M
authors: Chonchol
authors: Alfred K
authors: AK
authors: Cheung
authors: James S
authors: JS
authors: Kaufman
authors: Tom
authors: T
authors: Greene
authors: William L
authors: WL
authors: Roberts
authors: Gerard
authors: G
authors: Smits
authors: Jessica
authors: J
authors: Kendrick
mesh_terms: D000368:Aged; D015992:Body Mass Index; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D050171:Dyslipidemias / Q000097:blood*; D005260:Female; D000089703:Fibroblast Growth Factor-23; D005346:Fibroblast Growth Factors / Q000097:blood*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood / Q000401:mortality*; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D006435:Renal Dialysis; D014280:Triglycerides / Q000097:blood
chemical_list: D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; C000717427:FGF23 protein, human; D014280:Triglycerides; D005346:Fibroblast Growth Factors; D000089703:Fibroblast Growth Factor-23