GSTM1 and anemia (phenotype): Hospital mortality of HAA patients was higher and increased with severity of anemia, with 3.9% in mild anemia (Hb: >11 g/dL), 8.1% in moderate (Hb: 9-11 g/dL), and 18.3% in severe HAA (Hb: <9 g/dL) [10].