SP299CLINICALLY SIGNIFICANT ASSOCIATIONS WITH OUTCOMES OF STAGE 4 CHRONIC KIDNEY DISEASE DEPENDING ON THEIR DISTINCT DEFINITION BY SERUM CYSTATIN AND SERUM CREATININE BASED E-GFR (EPI) EQUATIONS. (13th June 2019) - Tavares, Joana; Silva, Filipa; Correia, Sofia; Oliveira, João; Campos, Andreia; Malheiro, Jorge; Santos, Josefina; Cabrita, António