Fluctuations in haemoglobin levels in haemodialysis, pre-dialysis and peritoneal dialysis patients receiving epoetin alpha or darbepoetin alpha.

AIM: To characterize the haemoglobin variability of haemodialysis, peritoneal dialysis and pre-dialysis patients treated with either epoetin alpha or darbepoetin alpha in a clinical setting where treatment was administered according to current standard Australian practice.
METHODS: Data on haemodialysis, pre-dialysis and peritoneal dialysis patients were extracted from the Renal Anaemia Management database (RAM) from 1 January 2001 to 31 December 2004. The variance in haemoglobin was calculated from patient records with more than five haemoglobin observations over a period of at least 4 weeks following 9 weeks of therapy. A mixed-model was fitted to the within-patient variances and weighting was based on the number of observations minus 1 for each record.
RESULTS: The mean within-patient variance in haemoglobin levels for i.v. administered erythropoietin-stimulating agents (IV) haemodialysis, s.c. administered erythropoietin-stimulating agents (SC) haemodialysis, predialysis (SC) and peritoneal dialysis (SC) patients receiving epoetin alpha were 9% (95% CI: 13% to 5%, P < 0.0001), 17% (95% CI: 32% to 0.2%, P = 0.047), 19% (95% CI: 27% to 11%, P < 0.0001) and 26% (95% CI: 33% to 18%, P < 0.0001) lower than that for patients receiving darbepoetin alpha. The mean haemoglobin levels for haemodialysis (IV), haemodialysis (sc) predialysis (SC) and peritoneal dialysis (SC) patients receiving darbepoetin alpha were 11.6 g/dL, 11.2 g/dL, 11.5 g/dL and 11.5 g/dL compared with 11.5 g/dL, 11.6 g/dL, 11.7 g/dL and 11.5 g/dL for patients receiving epoetin alpha.
CONCLUSION: There was 9-26% greater within-patient fluctuation in haemoglobin levels in patients receiving darbepoetin alpha compared with epoetin alpha. The causes of haemoglobin fluctuations and the implications for patient outcomes and resource use require further study.