title: Relationship of FGF23 to indexed left ventricular mass in children with non-dialysis stages of chronic kidney disease.
abstract: BACKGROUND
  The aim of this study was to evaluate the association of serum intact fibroblast growth factor 23 (FGF23) concentrations with indexed left ventricular mass in children with non-dialysis stages 3-5 of chronic kidney disease (CKD).
  
  
  METHODS
  The study cohort comprised 83 children (51 boys; mean age 12.1 ± 3.2 years) with a mean estimated glomerular filtration rate (eGFR) of 32.3 ± 14.6 ml/min/1.73 m(2) who underwent clinic and ambulatory blood pressure measurement (ABPM), echocardiography and evaluation of biochemical markers of CKD-associated mineral bone disease.
  
  
  RESULTS
  The mean left ventricular mass index (LVMI) was 35.9 ± 8.5 g/m(2.7) (± standard deviation), with 30 (36.1 %) children showing left ventricular hypertrophy (LVH), all eccentric, as defined using age-specific criteria. For all subjects, the mean FGF23 concentration was 142.2 ± 204.4 ng/l and the normalised distribution following log transformation was 1.94 ± 0.39. There was significant univariate correlation of LVMI with GFR, body mass index (BMI) z-score and calcium intake, but not with 24-h systolic ABPM z-score, log intact parathyroid hormone or log FGF23. On multivariate analysis following adjustment for confounders, only elemental calcium content (g/kg/day) estimated from prescribed calcium-based phosphate binder dose (β = 154.9, p < 0.001) and BMI z-score (β = 2.397, p = 0.003) maintained a significant positive relationship with LVMI (model r (2) = 0.225).
  
  
  CONCLUSIONS
  We observed no significant relationship of FGF23 with LVMI. Larger studies in children are needed to clarify the roles of calcium-containing phosphate binders and FGF23 with LV mass and their roles in the evolution of the development of adverse cardiovascular outcomes.
authors.affiliation: Department of Paediatric Nephrology, Evelina London Children's Hospital, Guys & St Thomas' NHS Foundation Trust, Room 64, Sky Level, Westminster Bridge Road, London, SE1 7EH, UK, manish.sinha@gstt.nhs.uk.
authors.forename: Manish D
authors.initials: MD
authors.lastname: Sinha
authors.forename: Charles
authors.initials: C
authors.lastname: Turner
authors.forename: Caroline J
authors.initials: CJ
authors.lastname: Booth
authors.forename: Simon
authors.initials: S
authors.lastname: Waller
authors.forename: Pernille
authors.initials: P
authors.lastname: Rasmussen
authors.forename: David J A
authors.initials: DJ
authors.lastname: Goldsmith
authors.forename: John M
authors.initials: JM
authors.lastname: Simpson
mesh_terms: D000293:Adolescent; D015415:Biomarkers / Q000097:blood; D001794:Blood Pressure / Q000502:physiology; D002648:Child; D002675:Child, Preschool; D003404:Creatinine / Q000097:blood; D003430:Cross-Sectional Studies; D018450:Disease Progression; D004452:Echocardiography; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D000089703:Fibroblast Growth Factor-23; D005346:Fibroblast Growth Factors / Q000097:blood*; D005919:Glomerular Filtration Rate; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000097:blood / Q000000981:diagnostic imaging* / Q000209:etiology; D008297:Male; D006435:Renal Dialysis; D051436:Renal Insufficiency, Chronic / Q000150:complications / Q000175:diagnosis / Q000378:metabolism*; D012720:Severity of Illness Index
chemical_list: D015415:Biomarkers; C000717427:FGF23 protein, human; D005346:Fibroblast Growth Factors; D000089703:Fibroblast Growth Factor-23; D003404:Creatinine