FGF23 and aortic valve calcification: Additionally, high levels of P and FGF-23 were also found as independent risk factors for mitral valve calcification (ORa = 1.078, p = 0.001; ORa = 1.209, p = 0.035), and aortic valve calcification (ORa = 1.497, p = 0.002; ORa = 1.126, p = 0.011) (Table 5).