GSTM1 and chronic kidney disease: The primary outcome of the US-based CHOIR study (N = 1432), which enrolled CKD patients with eGFR values of 15 to 50 mL/min/1.73 m2 and Hb levels <11 g/dL, was a composite of death, myocardial infarction, hospitalization for heart failure, or stroke [60].