It should be noted that intensive treatment of anemia especially with erythropoietin-stimulating agents to target the serum Hb levels of > 12 g/dL may disrupt cardiovascular safety.49 Furthermore, high levels of ferritin and hyperkalemia due to the administration of RBC could increase the risk of infection, hospitalization, and cardiovascular events.13 This evidence concerns the gene GSTM1 and anemia (phenotype).