Comparison of Darbepoetin Alfa (Aranesp) Dosing in Hospitalized Patients with Kidney Diseases

Background: Erythropoietin stimulating agents (ESAs) increase hemoglobin in kidney disease outpatients with anemia. Inflammation and acute illness reduce responsiveness to ESAs. There are no dosing guidelines for ESAs in kidney disease hospitalized patients with anemia. We compare two different dosing approaches with the ESA of darbepoetin alfa (DA). Methods: This was a retrospective study at South Brooklyn Health of 367 adult inpatients with kidney disease who received DA during hemodialysis and had a length of stay greater than two weeks after the initial dose. We compared DA doses of 60 mcg (DA60) (n=138, 37.6%) versus 100 mcg (DA100) (n=229, 62.4%). The primary outcome was difference in hemoglobin values two weeks after the baseline value upon start of DA. Secondary outcomes were hemoglobin differences from three weeks and four weeks after baseline and also safety outcomes. Results: The DA100 group had a significantly greater change in hemoglobin than the DA60 group at week two (DA100:M=0.36, SD=1.25 vs DA60:M=-0.08, SD=1.41, p=0.01) and week three (DA100:M=0.40, SD=1.45 vs DA60:M=-0.04, SD=1.26, p=0.01) but not at week four. There was no difference between the groups for safety outcomes of markedly elevated blood pressure, length of stay, or in-hospital mortality. Conclusion: In hospitalized kidney disease patients, initial dosing of 100 mcg of DA was associated with greater levels of increase in hemoglobin in the first 3 weeks as compared to initial dosing of 60 mcg. We recommend using the higher dose of 100 mcg of DA when treating hemoglobin concerns in hospitalized kidney disease patients.