EPOR and chronic kidney disease: The distribution plot suggested that approximately 5–6% of end-stage renal disease (ESRD) subjects had high circulating levels of EpoR (>2 standard deviations from the mean), and the subjects were divided accordingly The mean levels of sEpoR at the initiation of chronic hemodialysis were 2437±1299 pg/ml in the High group (n = 36) and 112±111 pg/ml in the Low group (n = 661) (p<0.001).