IGFBP2 and hydrops fetalis: It is known that IGF-1 functionality is affected by IGFBP-2 levels (98% of IGF-1 is bound to this protein) [33], so that an increase in IGFBP-2 levels in patients with CKD affects the peripheral function of the hormone and seems to be partially responsible for the association with a higher risk of mortality in patients with HF and CKD.