FGF23 and kidney disorder: While this cause and effect relationship is not yet established, elevated serum concentrations of FGF23 are associated with increased mortality in hemodialysis patients [4] and patients with stable coronary artery disease [5, 6] and are furthermore related to progression of left ventricular hypertrophy and renal disease as well as increased fat mass and dyslipidemia in elderly patients [7, 8].