GSTM1 and major depressive disorder: These included sex (p = 0.011), education level (p < 0.001), Hoehn-Yahr stage (p = 0.006), MDS-UPDRS-I (p = 0.006), MDS-UPDRS-II (p = 0.001), and MDS-UPDRS-III (p < 0.001), anxiety (p < 0.001), depression (p = 0.029), Hb (p < 0.001), and longer hospitalization duration (p = 0.002) (Table 1).