Stability of target hemoglobin levels during the first year of epoetin treatment in CKD patients.

Background and Objectives: Instability of hemoglobin levels during epoetin therapy is a new problem in hemodialysis. We evaluated extent and correlates of time in target, that is, the time spent with hemoglobin >11 g/dl during the first year of epoetin and its association with renal survival. Design, Setting, Participants, & Measurements: Data were collected in 917 visits for 12.0 mo in 119 patients with chronic kidney disease; thereafter, patients started renal survival analysis for 10.1 mo. At baseline, hemoglobin was 10.0 * 0.8 g/dl and GFR was 22.1 * 14.2 ml/min per 1.73 m2. Results: Hemoglobin target, reached in 1.5 mo, was steadily maintained in only 24% of patients. Time in target was not merely due to differences in time to target; after first achievement of target, in fact, a reduction of hemoglobin <11 g/dl occurred in 51% of patients. At multivariate analysis, male gender, basal GFR and hemoglobin levels, first epoetin dose, and iron supplementation were directly associated with length of time in target. A lower risk for renal death (dialysis n * 53; death n * 8) was detected in the higher tertile of time in target (11.3 mo) versus lower tertile (3.2 mo). This difference persisted at Cox analysis after adjustment for age, gender, GFR, BP, and proteinuria. Conclusions: In chronic kidney disease, time in target during the first year of epoetin therapy is frequently short depending not only on time to target but also on post-target hemoglobin reductions, correlates with male gender, timing, and intensity of initial therapy and is coupled with better renal survival.