title: Predictors of haemoglobin levels and resistance to erythropoiesis-stimulating agents in patients treated with low-flux haemodialysis, haemofiltration and haemodiafiltration: results of a multicentre randomized and controlled trial.
abstract: BACKGROUND
  Predictors of haemoglobin (Hb) levels and resistance to erythropoiesis-stimulating agents (ESAs) in dialysis patients have not yet been clearly defined. Some mainly uncontrolled studies suggest that online haemodiafiltration (HDF) may have a beneficial effect on Hb, whereas no data are available concerning online haemofiltration (HF). The objectives of this study were to evaluate the effects of convective treatments (CTs) on Hb levels and ESA resistance in comparison with low-flux haemodialysis (HD) and to evaluate the predictors of these outcomes.
  
  
  METHODS
  Primary multivariate analysis was made of a pre-specified secondary outcome of a multicentre, open-label, randomized controlled study in which 146 chronic HD patients from 27 Italian centres were randomly assigned to HD (70 patients) or CTs: online pre-dilution HF (36 patients) or online pre-dilution HDF (40 patients).
  
  
  RESULTS
  CTs did not affect Hb levels (P = 0.596) or ESA resistance (P = 0.984). Hb correlated with polycystic kidney disease (P = 0.001), C-reactive protein (P = 0.025), ferritin (P = 0.018), ESA dose (P < 0.001) and total cholesterol (P = 0.021). The participating centres were the main source of Hb variability (partial eta(2) 0.313, P < 0.001). ESA resistance directly correlated with serum ferritin (P = 0.030) and beta2 microglobulin (P = 0.065); participating centres were again a major source of variance (partial eta(2) 0.367, P < 0.001). Transferrin saturation did not predict either outcome variables (P = 0.277 and P = 0.170).
  
  
  CONCLUSIONS
  In comparison with low-flux HD, CTs did not significantly improve Hb levels or ESA resistance. The main sources of variability were participating centres, ESA dose and the underlying disease.
authors.affiliation: Department of Nephrology and Dialysis, Azienda Ospedaliera della Provincia di Lecco, Ospedale Alessandro Manzoni, Lecco, Italy. f.locatelli@ospedale.lecco.it
authors.forename: Francesco
authors.initials: F
authors.lastname: Locatelli
authors.forename: Paolo
authors.initials: P
authors.lastname: Altieri
authors.forename: Simeone
authors.initials: S
authors.lastname: Andrulli
authors.forename: Giovanna
authors.initials: G
authors.lastname: Sau
authors.forename: Piergiorgio
authors.initials: P
authors.lastname: Bolasco
authors.forename: Luciano A
authors.initials: LA
authors.lastname: Pedrini
authors.forename: Carlo
authors.initials: C
authors.lastname: Basile
authors.forename: Salvatore
authors.initials: S
authors.lastname: David
authors.forename: Mariano
authors.initials: M
authors.lastname: Feriani
authors.forename: Pier Eugenio
authors.initials: PE
authors.lastname: Nebiolo
authors.forename: Rocco
authors.initials: R
authors.lastname: Ferrara
authors.forename: Domenica
authors.initials: D
authors.lastname: Casu
authors.forename: Francesco
authors.initials: F
authors.lastname: Logias
authors.forename: Renzo
authors.initials: R
authors.lastname: Tarchini
authors.forename: Francesco
authors.initials: F
authors.lastname: Cadinu
authors.forename: Mario
authors.initials: M
authors.lastname: Passaghe
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Fundoni
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Villa
authors.forename: Biagio Raffaele
authors.initials: BR
authors.lastname: Di Iorio
authors.forename: Carmine
authors.initials: C
authors.lastname: Zoccali
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004351:Drug Resistance; D005260:Female; D005500:Follow-Up Studies; D006397:Hematinics / Q000009:adverse effects*; D017583:Hemodiafiltration; D006440:Hemofiltration; D006454:Hemoglobins / Q000378:metabolism*; D006801:Humans; D007674:Kidney Diseases / Q000378:metabolism / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D006435:Renal Dialysis; D012307:Risk Factors; D055815:Young Adult
chemical_list: D006397:Hematinics; D006454:Hemoglobins