Patients were classified into two groups based on the values of MCH and RBC, patients with MCH ≥30 pg but <35 pg and RBC ≤350×104/μL; and MCH <30 pg and RBC >350×104/μL. Associations between all-cause mortality and the distributions of MCH and RBC were assessed by Kaplan-Meier curves and Cox proportional hazards regression model.

The Hb levels generally provides the value of RBC and iron status because mean corpuscular hemoglobin MCH is derived from the Hb divided by RBC. MCH depends on the size and concentration of erythrocytes. Thus, the value of RBC and MCH depend on dose of ESA and iron, respectively. Guidelines for Renal Anemia in Chronic Kidney Disease of 2015 Japanese Society for Dialysis Therapy recommend administration hemoglobin (Hb) levels ≥10 g/dL but <12 g/dL in dialysis patients.Patients whose Hb levels is maintained at 10 to 12 g/dL, Hb levels is widely distributed when divided into RBC and MCH. Therefore, the investigators examined the prognosis of life in the distribution of MCH and RBC.

Inclusion Criteria:

• Patients will be controlled with hemoglobin levels between ≥10 g/dL and <12 g/dL and had undergone maintenance HD for >1 year.

Exclusion Criteria:

• Patients will be excluded if they have peritoneal dialysis combined with HD, do not have records of laboratory investigations during this period, or are transferred to another hospital or lost to follow-up.

Patients has undergone maintenance Hemodialysis for >1 year.