Study examines outcomes associated with anaemia management for patients with end-stage renal disease

Greater use of erythropoiesis-stimulating agents (ESAs) and more frequent use of iron at lower haematocrit levels (the proportion of the blood that consists of red blood cells) was associated with a decreased risk of death for haemodialysis patients, according to a study in the March 3 issue of JAMA.

'Appropriate use of ESAs [which stimulate red blood cell production] and intravenous iron can effectively manage the anaemia of chronic kidney disease and end-stage renal disease (ESRD), but several randomised trials have reported an increased risk of mortality and cardiovascular events in patients treated to achieve higher haematocrit levels. The earlier of these reports prompted the U.S. Food and Drug Administration in March 2007 to issue a black box warning for all ESAs recommending that they be used at the lowest level necessary to prevent transfusions,' the authors write. There is disagreement regarding the appropriate management of anaemia in ESRD.

M. Alan Brookhart, Ph.D., of the University of North Carolina, Chapel Hill, and colleagues assessed the 1-year mortality risk associated with different dialysis centre-level patterns of ESA and intravenous iron use for 269,717 new haemodialysis patients. Using data from Medicare's ESRD program (1999-2007), the researchers characterised each U.S. dialysis centre's annual anaemia management practice by estimating its typical use of ESAs and intravenous iron in haemodialysis patients within 4 haematocrit categories.

After adjustment for various factors, the researchers found that certain patterns of ESA and iron use by dialysis centres were associated with different mortality risks among new patients at those centres. Centres that used larger doses of ESAs in patients with haematocrit less than 30 percent achieved lower mortality rates, while mortality rates were increased in centres that used larger ESA doses in patients with haematocrit between 33 percent and 35.9 percent and in those with haematocrit of 36 percent or higher. 'We observed decreased mortality in centres that used iron more frequently in patients with haematocrit less than 30 percent and in patients with haematocrit between 30 percent and 32.9 percent. We also observed increasing mortality rates in centres that used iron more frequently in patients with haematocrit levels of 36 percent or higher,' the authors write.

'Further observational and experimental studies are needed to help identify optimal treatment algorithms for both ESAs and iron that maximise clinical benefit while minimising adverse outcomes.'