EPO and anemia (phenotype): Anemia Management and Erythropoietin-Stimulating Agent (ESA) Use: Prospective trials and cohort studies, including the RISchio CArdiovascolare nei pazienti afferenti all’ Area Vasta In Dialisi (RISCAVID) and the role of hemodiafiltration on ERI (REDERT), have demonstrated that HDF reduces the erythropoietin resistance index (ERI), improving anemia management [68,69,70].