Improvement of anemia with erythropoietin and intravenous iron reduces sleep-related breathing disorders and improves daytime sleepiness in anemic patients with congestive heart failure.

BACKGROUND: Central sleep apnea (CSA) (with or without Cheyne-Stokes breathing) or obstructive sleep apnea (OSA) are common in congestive heart failure (CHF). Correction of anemia may improve CHF. We hypothesized that correction of anemia might also improve sleep-related breathing disorders (SRBDs) in CHF. METHODS: Thirty-eight patients with CHF and anemia (hemoglobin level < 12 g/dL) were treated with erythropoietin and intravenous iron to a target hemoglobin level of 13 g/dL. Home sleep recordings were done before and after 3 months of treatment. RESULTS: Thirty-seven patients had SRBD (Apnea Hypopnea Index [AHI] of > or = 10). Hemoglobin level increased from 10.4 +/- 0.8 to 12.3 +/- 1.2 g/dL (P < .001). Total AHI values decreased from 35.9 +/- 12.2 to 24.9 +/- 12.2 (P < .001). The AHI of CSA, OSA and Cheyne-Stokes breathing decreased from 26.5 +/- 14.6 to 18.6 +/- 7.7, from 9.4 +/- 10.9 to 6.9 +/- 9.8, and from 13.1 +/- 16.4 to 9.0 +/- 12.2, respectively (all P < .05). Sleep minimal oxygen saturation (SaO2) increased from 62% +/- 12% to 71% +/- 11%; Epworth Sleepiness Scale score improved from 9.4 +/- 6.2 to 6.0 +/- 5.0 and New York Heart Association class improved from 2.9 +/- 0.4 to 1.7 +/- 0.7, all P < .001. Hemoglobin level improvement correlated with improvement in OSA+CSA, CSA, minimal SaO2, Epworth Sleepiness Scale score, and New York Heart Association class (all P < .001). CONCLUSION: Improvement of anemia in CHF is associated with a reduction in SRBD and an improvement in daytime sleepiness.

Anemia, chronic renal disease and congestive heart failure--the cardio renal anemia syndrome: the need for cooperation between cardiologists and nephrologists.

Many patients with congestive heart failure (CHF) fail to respond to maximal CHF therapy and progress to end stage CHF with many hospitalizations, poor quality of life (QoL), progressive chronic kidney disease (CKD) which can lead to end stage kidney disease (ESKD), or die of cardiovascular complications within a short time. One factor that has generally been ignored in many of these people is the fact that they are often anemic. The anemia in CHF is due mainly to the frequently-associated CKD but also to the inhibitory effects of cytokines on erythropoietin production and on bone marrow activity, as well as to their interference with iron absorption from the gut and their inhibiting effect on the release of iron from iron stores. Anemia itself may further worsen cardiac and renal function and make the patients resistant to standard CHF therapy. Indeed anemia in CHF has been associated with increased severity of CHF, increased hospitalization, worse cardiac function and functional class, the need for higher doses of diuretics, progressive worsening of renal function and reduced QoL. In both controlled and uncontrolled studies of CHF, the correction of the anemia with erythropoietin (EPO) and oral or intravenous (IV) iron has been associated with improvement in many cardiac and renal parameters and an increased QoL. EPO itself may also play a direct role in improving the heart unrelated to the improvement of the anemia--by reducing apoptosis of cardiac and endothelial cells, increasing the number of endothelial progenitor cells, and improving endothelial cell function and neovascularization of the heart. Anemia may also play a role in the worsening of acute myocardial infarction and chronic coronary heart disease (CHD) and in the cardiovascular complications of renal transplantation. Anemia, CHF and CKD interact as a vicious circle so as to cause or worsen each other- the so-called cardio renal anemia syndrome. Only adequate treatment of all three conditions can prevent the CHF and CKD from progressing.