GSTM1 and Stroke: The Correction of Hemoglobin and Outcomes in Renal Insufficiency (CHOIR) trial [14] and the Trial to Reduce Cardiovascular Events with Aranesp Therapy (TREAT) [15] conducted on pre-dialysis CKD patients showed that targeting higher Hb level compared with targeting lower Hb level increased the incidence of CVD events, especially stroke, and mortality.