Anemia Evaluation and Erythropoietin Dose Requirement Among Hemodialysis Patients: a Multicenter Study. 
Both anemia and high doses of erythropoietin have been associated with increased mortality among dialysis patients.  This study was conducted to evaluate the effective dose of erythropoiesis-stimulating agents.  This multicenter nationwide cross-sectional study assessed adult patients on hemodialysis for at least 3 months from 80 hemodialysis centers in Iran.  Demographic data, erythropoietin dose, and laboratory data were collected.  A total of 7009 prevalent hemodialysis patients were enrolled.  Fifty-five percent of the patients had their hemoglobin levels within the target values.  In those with a hemoglobin level of 8 g/dL to 10 g/dL, an erythropoietin dose of 10000 IU/wk to 12000 IU/wk led to a significant increase in hemoglobin level.  A mean erythropoietin dose of 7700 IU/wk was effective in maintaining the target hemoglobin of 10 g/dL to 12 g/dL during a 3-month follow-up period.  Improvement in hemoglobin level was associated with male sex, diabetes mellitus, and hemodialysis adequacy, and its deterioration with lower parathyroid hormone, calcium-phosphorus product, and creatinine levels; malnutrition; transfusion; and angiotensin-converting enzyme inhibitors and angiotensin receptor blockers (R2 = 29.1%, P < .001).  A dosage of 66.5 IU/kg/wk led to 1 g/dL increase in hemoglobin in anemic patients.  Data suggested that an estimated erythropoietin dose of 66.5 IU/kg/wk for each 1 g/dL hemoglobin level below the target could be used as a guide for prescription.  A dosage of about 8000 IU/wk could help maintaining hemoglobin within the target.  A longitudinal study is needed to estimate the required erythropoietin dose.