In a randomized,double blind trial, Swedberg et al evaluated the effects of darbepoetin alfa on clinical outcomes in patients with systolic heart failure and anemia.
Although darbepoetin alfa treatment led to an early and sustained increase in the hemoglobin concentration, the use of darbepoetin alfa did not reduce the risk of the primary outcome of death or hospitalization for worsening heart failure compared with placebo.
Moreover, more patients had thromboembolic events in the treatment group than in the placebo group, an observation similar to the findings of the TREAT study.
Therefore, the hemoglobin concentration may simply be a surrogate marker for poor prognosis, which indicates ESA resistance caused by inflammation, impaired iron utilization, or fluid retention in patients with CKD or congestive heart failure, rather than a therapeutic target.
Hemodilution was first described in pregnant women and is believed to be an adaptive mechanism.
During pregnancy, the maternal plasma volume expands 45% on average to meet the greater needs of the placental circulation. Therefore, hemoglobin concentrations are diluted and the threshold for a diagnosis of anemia, which is defined as hemoglobin