EPO and Huntington disease: The HD patients were further divided into 2 groups: (1) 36 EPO-resistant HD patients comprising 11 male and 25 female patients receiving a high dose of EPO ≥ 40,000 U/month for a minimum of 6 months and with Hct levels <33 %; and (2) 98 non-EPO-resistant HD patients comprising 35 male and 63 female patients receiving a low dose of EPO < 40,000 U/month for a minimum of 6 months and with Hct levels >33 %.