title: Hemoglobin variability with epoetin beta and continuous erythropoietin receptor activator in patients on peritoneal dialysis.
abstract: OBJECTIVE
  The extent to which hemoglobin (Hb) cycling occurs in peritoneal dialysis (PD) patients is unclear. It is also uncertain whether different types of erythropoiesis-stimulating agents (ESAs) affect such cycling. We performed a retrospective cohort study of our PD population before and after the entire program was switched from epoetin beta (NeoRecormon: Hoffman-LaRoche, Basel, Switzerland) to continuous erythropoietin receptor activator [CERA (Mircera: Hoffman-LaRoche)].
  
  
  METHODS
  The study included 79 patients receiving PD for end-stage renal failure and being treated with an ESA. Hemoglobin concentrations were measured monthly, and each study period ran for 12 months. Patient demographics and details of intercurrent illness and hospital admission were collected.
  
  
  RESULTS
  There was a trend to fewer patients on CERA (26 patients, 68.4%) than on epoetin beta (36 patients, 87.8%, p = 0.054) experiencing Hb excursions. The CERA group also required fewer dose changes. However, there was no difference in the proportion of patients experiencing complete Hb cycles. On logistic regression, the factors associated with Hb cycling were ESA dose increase or decrease and hospital admission. We also observed a positive correlation between the delta ESA dose and the amplitude of Hb excursion, suggesting that the dose changes were causal, rather than reactive.
  
  
  CONCLUSIONS
  Hemoglobin cycling occurs in PD patients and is largely a consequence of current practice in ESA dosing, plus the effects of intercurrent illness. The longer half life of CERA may offer a small advantage in reducing the degree of Hb variability, possibly because of fewer dose changes per patient.
authors: Department of Renal Medicine, University of Nottingham, Nottingham, UK. nick.selby@nhs.net
authors: Nicholas M
authors: NM
authors: Selby
authors: Sally A
authors: SA
authors: Fonseca
authors: Richard J
authors: RJ
authors: Fluck
authors: Maarten W
authors: MW
authors: Taal
mesh_terms: D000328:Adult; D000368:Aged; D000740:Anemia / Q000097:blood / Q000188:drug therapy* / Q000209:etiology; D004921:Erythropoietin / Q000627:therapeutic use*; D005260:Female; D006397:Hematinics / Q000627:therapeutic use*; D006454:Hemoglobins / Q000032:analysis / Q000378:metabolism*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D010530:Peritoneal Dialysis; D011092:Polyethylene Glycols / Q000627:therapeutic use*; D011994:Recombinant Proteins / Q000627:therapeutic use; D012189:Retrospective Studies
chemical_list: D006397:Hematinics; D006454:Hemoglobins; D011994:Recombinant Proteins; C508420:continuous erythropoietin receptor activator; C103998:epoetin beta; D004921:Erythropoietin; D011092:Polyethylene Glycols