Association between fibroblast growth factor 23 and left ventricular hypertrophy in maintenance hemodialysis patients. Comparison with B-type natriuretic peptide and cardiac troponin T.
BACKGROUND
Fibroblast growth factor 23 (FGF-23) is a novel bone-derived phosphate-regulating hormone, and serum FGF-23 levels are associated with mortality among hemodialysis (HD) patients. However, the pathophysiological role of FGF-23 in those patients remains unclear, so the association between serum FGF-23 levels and known cardiac biomarkers or echocardiographic measurements were investigated in long-term HD patients without cardiac symptoms.


RESULTS
The 87 consecutive patients treated in a single HD center (51 males, 36 females; mean age 64 years, mean HD duration 5.8 years) were included in this study. Comprehensive echocardiography was performed after HD. Blood samples were obtained before HD. Serum FGF-23 levels in dialysis patients were 1,171±553pg/ml. In univariate analysis, serum phosphate (r=0.443, P<0.001) and calcium levels (r=0.256, P=0.04), left ventricular mass index (LVMI) (r=0.268, P=0.039) were significantly associated with FGF-23 levels. Neither the B-type natriuretic peptide (BNP) nor the cardiac troponin T level was correlated with FGF-23. In multivariate regression analysis, only LVMI (β=0.287, P=0.031, confidence interval (CI) 0.390-8.040) and phosphate levels (β=0.419, P=0.001, CI 57.12-207.7) and calcium levels (β=0.277, P=0.025, CI 24.95-360.1) remained significantly correlated with FGF-23.


CONCLUSIONS
Beside BNP, FGF-23 was identified as a factor that is significantly associated with LVMI. FGF-23 could be a novel biomarker of left ventricular overload, which is closely associated with the increased risk of death in HD patients.
Department of Medicine and Biological Science, Gunma University Graduate School of Medicine, Maebashi, Japan. kazz.negishi@nifty.com
Kazuaki
K
Negishi
Mitsuru
M
Kobayashi
Izuru
I
Ochiai
Yuji
Y
Yamazaki
Hisashi
H
Hasegawa
Takeyoshi
T
Yamashita
Takehisa
T
Shimizu
Shu
S
Kasama
Masahiko
M
Kurabayashi
D000368:Aged; D015415:Biomarkers / Q000097:blood; D005260:Female; D000089703:Fibroblast Growth Factor-23; D005346:Fibroblast Growth Factors / Q000097:blood*; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000097:blood* / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D006435:Renal Dialysis; D012189:Retrospective Studies; D012307:Risk Factors; D020107:Troponin T / Q000097:blood*
D015415:Biomarkers; C000717427:FGF23 protein, human; D020107:Troponin T; D020097:Natriuretic Peptide, Brain; D005346:Fibroblast Growth Factors; D000089703:Fibroblast Growth Factor-23