title: Iron indices and survival in maintenance hemodialysis patients with and without polycystic kidney disease.
abstract: BACKGROUND
  Anemia is less prominent in patients with polycystic kidney disease (PKD). Such iron indices as ferritin and transferrin saturation (TSAT) values are used to guide management of anemia in individuals on maintenance hemodialysis (MHD). Optimal levels of correction of anemia and optimal levels of TSAT and ferritin are unclear in chronic kidney disease patients and have not been studied specifically in PKD.
  
  
  METHODS
  We studied 2969 MHD patients with and 128 054 patients without PKD from 580 outpatient hemodialysis facilities between July 2001 and June 2006. Using baseline, time-dependent and time-averaged values with unadjusted and multivariable adjusted analysis models, the survival predictabilities of TSAT and ferritin were studied.
  
  
  RESULTS
  PKD patients were 58 ± 13 years old and included 46% women, whereas non-PKD patients were 62 ± 15 years old and 45% women. In both PKD and non-PKD patients, a time-averaged TSAT between 30 and 40% was associated with the lowest mortality. Time-averaged ferritin between 100 and <800 ng/mL was associated with the lowest mortality in PKD patients, although this range was 500 to <800 ng/mL in non-PKD patients.
  
  
  CONCLUSIONS
  In MHD patients with and without PKD, there was a U-shaped relationship between the average TSAT and mortality, and a TSAT of 30-40% was associated with the best survival. However, an average ferritin of 100-800 ng/mL was associated with the best survival in PKD patients, whereas that of non-PKD patients was 500-800 ng/mL. Further studies in PKD and non-PKD patients are necessary to determine whether or not therapeutic attempts to keep TSAT and ferritin levels in these ranges will improve survival.
authors.affiliation: Harold Simmons Center for Kidney Disease Research and Epidemiology, Division of Nephrology and Hypertension, UC Irvine Medical Center, Orange, CA, USA.
authors.forename: Parta
authors.initials: P
authors.lastname: Hatamizadeh
authors.forename: Vanessa
authors.initials: V
authors.lastname: Ravel
authors.forename: Lilia R
authors.initials: LR
authors.lastname: Lukowsky
authors.forename: Miklos Z
authors.initials: MZ
authors.lastname: Molnar
authors.forename: Hamid
authors.initials: H
authors.lastname: Moradi
authors.forename: Kevin
authors.initials: K
authors.lastname: Harley
authors.forename: Madeline
authors.initials: M
authors.lastname: Pahl
authors.forename: Csaba P
authors.initials: CP
authors.lastname: Kovesdy
authors.forename: Kamyar
authors.initials: K
authors.lastname: Kalantar-Zadeh
mesh_terms: D000740:Anemia / Q000188:drug therapy; D016022:Case-Control Studies; D005260:Female; D005293:Ferritins / Q000097:blood*; D006801:Humans; D007501:Iron / Q000627:therapeutic use; D007676:Kidney Failure, Chronic / Q000150:complications* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D007690:Polycystic Kidney Diseases / Q000209:etiology / Q000378:metabolism / Q000401:mortality*; D011379:Prognosis; D006435:Renal Dialysis / Q000401:mortality*; D015996:Survival Rate
chemical_list: D005293:Ferritins; D007501:Iron
keywords: ferritin; hemodialysis; iron; polycystic kidney disease; transferrin saturation