Maintenance of target hemoglobin level in stable hemodialysis patients constitutes a theoretical task: a historical prospective study

Maintenance of target hemoglobin (Hb) values in hemodialysis patients treated with erythropoiesis-stimulating agents (ESAs) remains difficult. We examined Hb variability in the clinical setting in hemodialysis patients. Hemodialysis patients treated with ESAs who maintained the recommended Hb range of 11-13 g per 100 ml over 3 months and were not admitted to hospital, did not require transfusion, and did not experience any major clinical event during this period were followed prospectively for 1 year. Anemia events, Hb variation events (any value out of +/- 1.5 g per 100 ml of the median Hb level in the total follow-up period for the individual patient), risk factors for anemia, and Hb variation events were assessed. We studied 420 patients (63% males, mean age 61 years), 222 received short-acting erythropoietin (EPO) and 198 long-acting darbepoetin. A total of 4654 blood samples (mean 11.1 per patient-year) were analyzed. Only 3.8% of patients were maintained within the target Hb levels (11-13 g per 100 ml) during 1 year. Hb variation events occurred in 20.8% of laboratory values and anemia events in 14.7%, with a median time to the first event of 3 months. Treatment with short-acting EPO (vs long-acting darbepoetin), change of ESA dose in the previous visit, resistance index, and hospitalization were significant risk factors for both anemia events and Hb variation events. Our results show that Hb values are rarely maintained within the recommended guidelines even in more stable hemodialysis patients. Hb variability is frequently associated with clinical events or ESA dose changes. Long-acting darbepoetin achieved better Hb stability than short-acting EPO.