Anemia, Polycythemia and Kidney Disease Add Up to Deadly Heart Failure Trio

OAKLAND, Calif., June 8 ? Anemia, polycythemia, and chronic kidney disease are independent predictors of outcome for patients with heart failure, according to researchers here.

Moreover, the predictive value of hemoglobin levels and glomerular filtration rate was evident even among patients with preserved or reduced systolic function and was independent of underlying kidney dysfunction, found Alan S. Go, M.D., and colleagues, of the division of research at Kaiser Permanente of Northern California.

The ANCHOR study (Anemia in Chronic Heart Failure: Outcomes and Resource Utilization), reported online in Circulation, Journal of the American Heart Association, examined the association between hemoglobin level, kidney function, and risks of death or hospitalization among 59,772 adults with heart failure treated between 1996 and 2002. The mean age of the patients was 72, and 46% were women.

Among the findings:

• Compared with normal hemoglobin levels (13.0 to 13.9 g/dL) the risk of death increased as levels fell and was more than three times higher for patients with levels less than 9.0 g/dl (HR 3.48 [95% C.I. 3.25 to 3.73]).
• Among those patients with hemoglobin levels of 17.0 g/L or more there was a 40% increase in risk of death (HR 1.42; 95% C.I. 1.24 to 1.63).
• As kidney function decreased and glomerular filtration rate fell to below 60 mL.min^-1 the risk of death increased. For patients with glomerular filtration rate of less than 15 mL min^-1 there was a three-fold increase in risk of death (HR 3.26, 95% CI 3.05 to 3.49), which was greater than the risk observed for patients on dialysis (HR 2.44, 95% CI 2.28 to 2.61).
• Patients with polycythemia were more likely to have diagnosed lung disease (34.8% versus 26.2 in patients without polycythemia P

Also the authors wrote that the study was limited by the lack of LV function status, New York Heart Association severity classification, and B-type natriuretic peptide measurements for a number of patients. In addition, they pointed out that residual confounding due to heart severity cannot be completely ruled out.

The authors concluded that because anemia is both common and modifiable among patients with heart failure, the logical next step is a large, randomized trial to determine whether treating anemia with recombinant erythropoietin and/or iron therapy may reduce the risk of adverse clinical outcomes in heart failure.

The study was funded by Amgen, the maker of Aranesp (darbepoetin alfa), which is approved for treatment of anemia.