Fibroblast growth factor 23 and left ventricular hypertrophy in children on dialysis.
BACKGROUND
Elevated fibroblast growth factor 23 (FGF-23) concentrations associate with left ventricular hypertrophy (LVH) and adverse outcomes in adult patients with chronic kidney disease. We hypothesized that similar associations are present in pediatric patients on maintenance hemodialysis.


METHODS
In this retrospective study of 26 young patients on chronic hemodialysis, aged 6-21 years, cardiac structure and geometry were measured by echocardiography, and circulating levels of FGF-23 and calciotropic hormones were obtained.


RESULTS
FGF-23 levels were uniformly elevated in all patients from three- to 835-fold above the upper limit of normal. The average LV mass index (LVMI) was 43 ± 13 g/m(2.7) and reflected LVH in 55 % of patients. Log-transformed FGF-23 concentrations correlated with LVMI (p = 0.03) and were independently associated with the interventricular septal thickness Z-score (p < 0.001). Concentric LVH was associated with the highest FGF-23 concentrations and the highest LVMI measurements (p < 0.001). Each 1 standard deviation increase in log-transformed FGF-23 levels was associated with a 17 % increase in LVMI.


CONCLUSIONS
FGF-23 levels are strongly associated with increased LVMI and with prevalent LVH in pediatric hemodialysis patients. Our cross-sectional findings provide observational evidence supporting the hypothesis linking FGF-23 to cardiac hypertrophy in patients with chronic kidney disease.
Division of Pediatric Nephrology, University of Miami Miller School of Medicine and Holtz Children's Hospital/Jackson Memorial Medical Center, PO Box 016960 (M-714), Miami, FL, 33101, USA.
Wacharee
W
Seeherunvong
Division of Pediatric Nephrology, University of Miami Miller School of Medicine and Holtz Children's Hospital/Jackson Memorial Medical Center, PO Box 016960 (M-714), Miami, FL, 33101, USA.
Carolyn L
CL
Abitbol
Division of Pediatric Nephrology, University of Miami Miller School of Medicine and Holtz Children's Hospital/Jackson Memorial Medical Center, PO Box 016960 (M-714), Miami, FL, 33101, USA.
Jayanthi
J
Chandar
Division of Pediatric Cardiology, University of Miami Miller School of Medicine and Holtz Children's Hospital/Jackson Memorial Medical Center, Miami, FL, USA.
Paolo
P
Rusconi
Division of Pediatric Nephrology, University of Miami Miller School of Medicine and Holtz Children's Hospital/Jackson Memorial Medical Center, PO Box 016960 (M-714), Miami, FL, 33101, USA.
Gaston E
GE
Zilleruelo
Division of Pediatric Nephrology, University of Miami Miller School of Medicine, PO Box 016960 (M-714), Miami, FL, 33101, USA. mfreundlich@med.miami.edu.
Michael
M
Freundlich
D000293:Adolescent; D000367:Age Factors; D015415:Biomarkers / Q000097:blood; D002118:Calcium / Q000097:blood; D002648:Child; D015897:Comorbidity; D003430:Cross-Sectional Studies; D015150:Echocardiography, Doppler; D000089703:Fibroblast Growth Factor-23; D005346:Fibroblast Growth Factors / Q000097:blood*; D005431:Florida / Q000453:epidemiology; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000097:blood* / Q000000981:diagnostic imaging / Q000453:epidemiology; D015999:Multivariate Analysis; D010281:Parathyroid Hormone / Q000097:blood; D010710:Phosphates / Q000097:blood; D015995:Prevalence; D006435:Renal Dialysis / Q000009:adverse effects; D051436:Renal Insufficiency, Chronic / Q000097:blood / Q000453:epidemiology / Q000628:therapy*; D012189:Retrospective Studies; D015854:Up-Regulation; D014807:Vitamin D / Q000031:analogs & derivatives / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood / Q000453:epidemiology; D055815:Young Adult
D015415:Biomarkers; C000717427:FGF23 protein, human; C470125:PTH protein, human; D010281:Parathyroid Hormone; D010710:Phosphates; D014807:Vitamin D; D005346:Fibroblast Growth Factors; C097949:1,25-dihydroxyvitamin D; D000089703:Fibroblast Growth Factor-23; C104450:25-hydroxyvitamin D; D002118:Calcium