GSTM1 and Renal insufficiency: However, a secondary analysis of Hb Correction and Outcomes in Renal Insufficiency (CHOIR) trial reported that the higher Hb target group had a higher rate of initiating renal replacement therapy (RRT) and a higher composite endpoint risk for CKD progression (creatinine doubling, RRT start, or death), and increases the rate of CKD progression [23].