Anemia treatment in the pre-ESRD period and associated mortality in elderly patients

Background Anemia is a common complication of advancing chronic kidney disease, yet little is known about the consistency of anemia treatment before end-stage renal disease (ESRD) and mortality on dialysis therapy. Methods: We studied 89,193 incident Medicare patients with ESRD in 1995 to 1997 aged 67 plus years with claims 2 years before their dialysis therapy initiation. Patients were classified as follows: no epoetin, 25% or less (least consistent), greater than 25% to 50%, greater than 50% to 75%, and greater than 75% (most consistent) epoetin treatment in the available months from the first pre-ESRD epoetin dose to the first ESRD service date. Cox regression modeled the risk for 1-year death in the post-ESRD period, adjusting for age, sex, race, diabetic status, albumin level, and incidence year. Results: Sixty percent of patients had hematocrits less than 30% at ESRD initiation, yet only 15.6% (N = 13,877) had epoetin claims before ESRD. The most consistent epoetin treatment group had hematocrits increase from 27.5% to 30.8% (P < 0.0001) by month 4 of treatment. Patients with the most consistent epoetin treatment had a greater mean hematocrit (29.2% 0.11%; P < 0.0001) and albumin level (3.31 +/- 0.01 g/dL [33.1 g/L]) at initiation than those with the least consistent treatment (28.1% +/- 0.10% and 3.21 +/- 0.01 g/dL [32.1 g/L], respectively). The relative risk for death in patients with the least consistent versus the most consistent (the reference) epoetin treatment was 1.460 (95% Cl, 1.245 to 1.713; P < 0.0001) 1 year after the first ESRD service date. Conclusion: Elderly patients with consistent pre-ESRD epoetin treatment had lower risks for death in the first year of dialysis therapy after ESRD initiation.