NEW YORK, NY--(Marketwired - Oct 25, 2013) - Daxor Corporation, (
The study focused on the problem of treatment of anemia, a very common complication seen in congestive heart failure patients. Anemia is usually diagnosed by measurement of the hematocrit or hemoglobin, which are tests which only measure the concentration of red blood cells but not their volume. The treatment of anemia is treated with ESA stimulants such as Arinesp, manufactured by the Amgen Corporation. There have been conflicting reports about the benefit of using this drug which stimulates the bone marrow to make more red blood cells in congestive heart failure patients.
It has been previously noted that some patients do not respond to the ESA drug and may actually have higher complications. They are called hyporesponders. In contrast, another group of heart failure patients do respond with increased red blood cells and improved symptoms to the same drug. They are termed responders. The study found that the patients who were responders were patients who did not have an enlarged blood volume and had a true anemia. In contrast, the patients who were determined to be hyporesponders had significantly enlarged blood volumes due to their plasma volume enlargement. In effect, the red blood cells which traveled with the plasma in the circulation are diluted by the expanded plasma or water part of the blood volume. The result of this is that these patients who do not respond well to ESA stimulants have, in effect, a false or pseudo anemia. This occurs because the standard tests (such as the hemaatocrit/hemoglobin) only measure the concentration of red blood cells, but not their actual volume. Blood volume can only be measured using a direct measurement such as provided by the blood volume analyzer.
The authors made the following observations in their published paper:
- "We suggest that blood volume analysis, by identifying subjects with a hemodilutional basis of their anemia, may enhance the application of ESAs to subjects with volume overloaded states and concomitant anemia and could potentially reduce the exposure of non-responders to ESA, a cohort that has been identified previously as increased risk of serious adverse effects" (emphasis added).
- "Blood volume was not only a useful baseline assessment, but also provided insights into the mechanism by which ESAs increase hemoglobin. We found that Erythropoietin Alfa affects both red cell and plasma volumes... clearly reductions in the rennin angiotensin/aldosterone would be a value in patients with heart failure resulting in declines in plasma volume as reported by others in systolic heart failure."
- The author's final statements were, "In older adults with HFPEF and anemia, blood volume analysis performed before administration of ESA therapy identified patients who had a poor response to Erythropoietin Alfa in terms of increases in hemoglobin. Hyporesponders had a hemodilutional basis of their anemia with no significant red cell deficit but with marked plasma volume execs. Finally, blood volume analysis demonstrated that although increase in red cell volume is the main mechanism by which Erythropoietin increases hemoglobin, reduction in plasma is also an important contributor to this process."
Dr. Joseph Feldschuh, a cardiologist and co-inventor of the blood volume analyzer, stated, "This is another important piece of research documenting the necessity that physicians treating congestive heart failure patients should be doing blood volume measurements to ensure that the patients are being treated optimally. Blood volume derangement is a primary derangement in congestive heart failure patients. The financial penalties that Medicare has imposed in 2013, which will increase in 2014 and 2015, will be another factor that hospital administrators will consider in avoiding 30-day readmission of congestive heart failure patients. At the present time 20 - 25% of congestive heart failure patients are readmitted within 30 days or less."
The Amgen Corporation, manufacturer of ESA drugs, has previously been required by the FDA to issue black box warnings in conjunction with the use of these agents. ESA agents have very important benefits. However, used inappropriately, they can cause severe complications. Blood volume measurement can help define which patients should be treated with these drugs and which patients should not be treated with such drugs.