Therapy insight: congestive heart failure, chronic kidney disease and anemia, the cardio-renal-anemia syndrome.

Congestive heart failure (CHF) and chronic kidney disease (CKD) often progress to end stage even with optimum medical therapy. One factor that is common to both conditions is anemia, which is present in about a third of CHF patients. CHF can cause or worsen both anemia and CKD, and CKD can cause or worsen both anemia and CHF. Thus, a vicious circle exists between these three conditions, with each causing or worsening the other. We have called this condition the cardio-renal-anemia syndrome. Anemia in CHF is associated with increased mortality and hospitalization, reduced cardiac function and evidence of more severe CHF and CKD than in nonanemic patients. Intervention studies in anemic CHF patients have shown that optimum medical treatment of CHF and the correction of the associated anemia with subcutaneous erythropoietin and oral iron or intravenous iron sucrose can improve cardiac function, patients' functional status, renal function and quality of life, and reduce the frequency of hospitalization and the dose of diuretics required.