Anemia complicates heart failure, should be new focus, doctor says
(Embargoed) CHAPEL HILL -- Anemia, a condition arising when the blood contains too few red cells and hence not enough of the oxygen-carrying pigment known as hemoglobin, appears to be an under-appreciated contributor to problems associated with congestive heart failure (CHF), a University of North Carolina at Chapel Hill cardiologist says. That's important, he says, because an estimated 25 percent of all Americans over age 40 will develop heart failure before they die.
"Five million or so people have been diagnosed with, and are living with, congestive heart failure," said Dr. Kirkwood F. Adams Jr. "Because of changes in the age of our population, that number is predicted to double within a decade, and as a result, both the economic burden and the magnitude of CHF in terms of sickness and death will continue to grow. In the past, anemia has been a neglected aspect of the condition, and that needs to change if we're going to serve patients well."
Associate professor of medicine and radiology and director of the UNC Heart Failure Program, Adams prepared his remarks for delivery Thursday (June 6) at an American Medical Association briefing on anemia in New York City.
Raising hemoglobin levels through treatment with drugs that mimic erythropoietin, which boosts red cell production, might help CHF patients by improving heart function and improving their limited ability to exercise, the physician said. Researchers already have made significant progress in treating CHF in recent years, particularly with such drugs as beta-blockers.
"But up to 40 percent of patients can't take beta-blockers long-term, and so seeking additional treatments is still important," Adams said.
In people suffering from heart failure, poor blood flow contributes to systemic changes, including impaired kidney function, he said. For various reasons, patients often become anemic.
"We recognized this anemia in the past, but many physicians questioned whether it needed to be treated if it was only moderate," Adams said. "Recent studies, however, have suggested that anemia adversely affects heart function not only in dialysis patients but in CHF patients as well."
Among those studies have been clinical trials indicating that among hospitalized heart attack victims, depression of hemoglobin, even to a limited degree, was linked to increased mortality, he said.
"Then clinicians began looking at this in CHF and began finding that anemia-reduced hemoglobin was an independent predictor of adverse outcomes," Adams said.
Two recent small and preliminary studies have further shown that hemoglobin increased in patients treated with erythropoietin and that those patients' ability to exercise improved, he said. One study even suggested that the drug could cut time spent in the hospital.
UNC serves as the coordinating center for a national heart failure registry, UNITE-HF, composed of 15 academic medical centers that collect and pool patient data for study. Working with Amgen, a drug company, and registry data, Adams and colleagues have begun studying the effects of anemia on patients' physical activity and fatigue, how hormones affect anemia and quality-of-life issues.
"This focus on anemia is new, and it is definitely worth investigating because we believe it may make a difference with many congestive heart failure patients, and results so far have been encouraging," the physician said.
Note: To register for a noon EDT conference call June 6 about the briefing, e-mail Christina_Catron@assn.org or call (312) 464-5980. Interested reporters should call 1-800-406-5345 a few minutes before noon to participate. Adams can be reached at (919) 966-4445 or KFA@med.unc.edu after he returns to Chapel Hill.
Contact: David Williamson, (919) 962-8596 By DAVID WILLIAMSON UNC News Services