Issues related to iron replacement in chronic kidney disease

Recent epidemiologic studies show that iron deficiency occurs in the vast majority of patients with chronic kidney disease (CKD). In patients with CKD, increased iron losses and, to a lesser extent, poor oral absorption, can lead to iron-deficiency anemia. Correction of iron-deficiency anemia is preferable by the oral route, however, data on oral iron use are limited in this population. In CKD patients, parenteral iron administered with recombinant human erythropoietin (rHuEpo), is the best potential option for the correction of anemia. Nondextran iron preparations are preferable because of a reduced incidence of serious adverse events. Parenteral iron in CKD patients may not be entirely innocuous and, although commonly used, have not received Food and Drug Administration approval for use in this patient population. Exposure to intravenous (IV) iron may lead to oxidative stress, renal injury, infection, cardiovascular disease, and osteomalacia. Studies are needed to confirm the existence and magnitude of these complications. The current data suggest that the overall risk-benefit ratio favors use of IV iron when compared with untreated or partially treated iron-deficiency anemia.

Safety and efficacy of sodium ferric gluconate complex in patients with chronic kidney disease

BACKGROUND

We hypothesized that intravenous iron will improve hemoglobin (Hgb) concentrations in anemic patients with chronic kidney disease (CKD), and the response would be greater if the underlying erythropoietin deficiency also was treated.

METHODS

Charts of 58 CKD veterans (glomerular filtration rate < 80 mL/min) administered at least 125 mg of sodium ferric gluconate complex in sucrose (SFGC) during a period of 1 year for the primary outcome of an increase in Hgb level by at least 0.5 g/dL were reviewed.

RESULTS

Mean Hgb level at baseline was 10.5 +/- 1.4 (SD) g/dL (105 +/- 14 g/L) in the 30 patients administered recombinant human erythropoietin (rHuEPO) plus SFGC and 10.1 +/- 1.3 g/dL (101 +/- 13 g/L) in the 28 patients administered SFGC alone (P = not significant). The primary event occurred in 83% of the rHuEPO-plus-SFGC group at 31 days compared with 60% at 62 days in the group administered SFGC alone (P = 0.037, Cox F test). In patients administered SFGC alone, mean maximal Hgb level was 11.4 +/- 0.9 g/dL (114 +/- 9 g/L) in contrast to 12.4 +/- 1.7 g/dL (124 +/- 17 g/L) in the combination group, which remained significantly different even after adjustment for biologically important covariates (P = 0.01, analysis of covariance). Of the 240 doses of SFGC administered for which infusion records were available, 237 doses were well tolerated; three hypotensive episodes occurred in 2 patients, which did not result in discontinuation of the drug in either case.

CONCLUSION

Correction of anemia with parenteral iron alone suggests a high prevalence of iron deficiency in patients with CKD. Treatment of concomitant iron deficiency with SFGC was well tolerated in patients with CKD and appears to optimize management of anemia.