FGF23 and chronic kidney disease: Among the various CKD stage subgroups (G1/G2, G3a, G3b, G4, G5), the correlation between FGF23 and LVMI was significant among those with CKD stage G1/G2, G3a, and G4 (Fig 2A) and that between FGF23 and LVEF was significant among those with CKD stage G1/G2, and G4 (Fig 2B).