Challenging the validity of the EPO index

George Kaysen, Hans G. Müller, Jimin Ding, Glenn M. Chertow

Research output: Contribution to journalArticle

43 Citations (Scopus)

Abstract

Background: With use of recombinant erythropoietin (EPO) and intravenous iron, the majority of hemodialysis patients can achieve target hemoglobin concentrations. EPO resistance arises as a consequence of inflammation and other processes that can adversely affect survival. We hypothesized that the EPO dose-hematocrit (EPO/Hct) ratio, also known as the EPO index, may be a surrogate for inflammation and that greater EPO/Hct ratios would be associated with decreased survival. Methods: We used proportional hazards regression models and time-varying logistic models to analyze the association between EPO index and survival in US hemodialysis patients initiating hemodialysis therapy between January 1, 1999, and December 31, 2000, and followed up for up to 3 years until December 31, 2001. Results: We found an unexpected and consistent association between greater EPO index and survival in all models. The associations of EPO/Hct ratio were most prominent at intermediate Hct values and with longer dialysis vintage. Iron administration was associated with a lower risk for death independent of Hct. Conversely, greater average prior EPO dose was associated with a greater risk for death. Conclusion: EPO resistance may be reflected better by total cumulative EPO dose than the EPO/Hct ratio. The mechanism(s) responsible for the association between a greater EPO/Hct ratio and survival remains to be established, but may be a result of nonerythrogenic effects of EPO.

Original languageEnglish (US)
JournalAmerican Journal of Kidney Diseases
Volume47
Issue number1
DOIs
StatePublished - Jan 2006

Fingerprint

Erythropoietin
Survival
Renal Dialysis
Iron
Inflammation
Hematocrit
Proportional Hazards Models
Dialysis
Hemoglobins
Logistic Models

Keywords

  • Anemia
  • End-stage renal disease (ESRD)
  • Hemodialysis (HD)
  • Inflammation
  • Iron
  • Mortality

ASJC Scopus subject areas

  • Nephrology

Cite this

Challenging the validity of the EPO index. / Kaysen, George; Müller, Hans G.; Ding, Jimin; Chertow, Glenn M.

In: American Journal of Kidney Diseases, Vol. 47, No. 1, 01.2006.

Research output: Contribution to journalArticle

Kaysen, George ; Müller, Hans G. ; Ding, Jimin ; Chertow, Glenn M. / Challenging the validity of the EPO index. In: American Journal of Kidney Diseases. 2006 ; Vol. 47, No. 1.
@article{650a3c09871d4426b068083b94455637,
title = "Challenging the validity of the EPO index",
abstract = "Background: With use of recombinant erythropoietin (EPO) and intravenous iron, the majority of hemodialysis patients can achieve target hemoglobin concentrations. EPO resistance arises as a consequence of inflammation and other processes that can adversely affect survival. We hypothesized that the EPO dose-hematocrit (EPO/Hct) ratio, also known as the EPO index, may be a surrogate for inflammation and that greater EPO/Hct ratios would be associated with decreased survival. Methods: We used proportional hazards regression models and time-varying logistic models to analyze the association between EPO index and survival in US hemodialysis patients initiating hemodialysis therapy between January 1, 1999, and December 31, 2000, and followed up for up to 3 years until December 31, 2001. Results: We found an unexpected and consistent association between greater EPO index and survival in all models. The associations of EPO/Hct ratio were most prominent at intermediate Hct values and with longer dialysis vintage. Iron administration was associated with a lower risk for death independent of Hct. Conversely, greater average prior EPO dose was associated with a greater risk for death. Conclusion: EPO resistance may be reflected better by total cumulative EPO dose than the EPO/Hct ratio. The mechanism(s) responsible for the association between a greater EPO/Hct ratio and survival remains to be established, but may be a result of nonerythrogenic effects of EPO.",
keywords = "Anemia, End-stage renal disease (ESRD), Hemodialysis (HD), Inflammation, Iron, Mortality",
author = "George Kaysen and M{\"u}ller, {Hans G.} and Jimin Ding and Chertow, {Glenn M.}",
year = "2006",
month = "1",
doi = "10.1053/j.ajkd.2005.09.013",
language = "English (US)",
volume = "47",
journal = "American Journal of Kidney Diseases",
issn = "0272-6386",
publisher = "W.B. Saunders Ltd",
number = "1",

}

TY - JOUR

T1 - Challenging the validity of the EPO index

AU - Kaysen, George

AU - Müller, Hans G.

AU - Ding, Jimin

AU - Chertow, Glenn M.

PY - 2006/1

Y1 - 2006/1

N2 - Background: With use of recombinant erythropoietin (EPO) and intravenous iron, the majority of hemodialysis patients can achieve target hemoglobin concentrations. EPO resistance arises as a consequence of inflammation and other processes that can adversely affect survival. We hypothesized that the EPO dose-hematocrit (EPO/Hct) ratio, also known as the EPO index, may be a surrogate for inflammation and that greater EPO/Hct ratios would be associated with decreased survival. Methods: We used proportional hazards regression models and time-varying logistic models to analyze the association between EPO index and survival in US hemodialysis patients initiating hemodialysis therapy between January 1, 1999, and December 31, 2000, and followed up for up to 3 years until December 31, 2001. Results: We found an unexpected and consistent association between greater EPO index and survival in all models. The associations of EPO/Hct ratio were most prominent at intermediate Hct values and with longer dialysis vintage. Iron administration was associated with a lower risk for death independent of Hct. Conversely, greater average prior EPO dose was associated with a greater risk for death. Conclusion: EPO resistance may be reflected better by total cumulative EPO dose than the EPO/Hct ratio. The mechanism(s) responsible for the association between a greater EPO/Hct ratio and survival remains to be established, but may be a result of nonerythrogenic effects of EPO.

AB - Background: With use of recombinant erythropoietin (EPO) and intravenous iron, the majority of hemodialysis patients can achieve target hemoglobin concentrations. EPO resistance arises as a consequence of inflammation and other processes that can adversely affect survival. We hypothesized that the EPO dose-hematocrit (EPO/Hct) ratio, also known as the EPO index, may be a surrogate for inflammation and that greater EPO/Hct ratios would be associated with decreased survival. Methods: We used proportional hazards regression models and time-varying logistic models to analyze the association between EPO index and survival in US hemodialysis patients initiating hemodialysis therapy between January 1, 1999, and December 31, 2000, and followed up for up to 3 years until December 31, 2001. Results: We found an unexpected and consistent association between greater EPO index and survival in all models. The associations of EPO/Hct ratio were most prominent at intermediate Hct values and with longer dialysis vintage. Iron administration was associated with a lower risk for death independent of Hct. Conversely, greater average prior EPO dose was associated with a greater risk for death. Conclusion: EPO resistance may be reflected better by total cumulative EPO dose than the EPO/Hct ratio. The mechanism(s) responsible for the association between a greater EPO/Hct ratio and survival remains to be established, but may be a result of nonerythrogenic effects of EPO.

KW - Anemia

KW - End-stage renal disease (ESRD)

KW - Hemodialysis (HD)

KW - Inflammation

KW - Iron

KW - Mortality

UR - http://www.scopus.com/inward/record.url?scp=29244487098&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=29244487098&partnerID=8YFLogxK

U2 - 10.1053/j.ajkd.2005.09.013

DO - 10.1053/j.ajkd.2005.09.013

M3 - Article

C2 - 16377397

AN - SCOPUS:29244487098

VL - 47

JO - American Journal of Kidney Diseases

JF - American Journal of Kidney Diseases

SN - 0272-6386

IS - 1

ER -