Intravenous Versus Oral Iron Supplementation for the Treatment of Anemia in CKD: Systematic Review and Meta-analysis
Received 31 January 2008; accepted 21 May 2008. published online 09 October 2008.
Background
Iron supplementation is essential for the treatment of patients with anemia of chronic kidney disease (CKD). It is not clear which is the best method of iron administration.
Study Design
Systematic review and meta-analysis. A search was performed until January 2008 of MEDLINE, Cochrane Central Register of Controlled Trials, conference proceedings in nephrology, and reference lists of included trials.
Setting & Population
Patients with CKD (stages III to V). We included dialysis patients and patients with CKD not on dialysis therapy (hereafter referred to as patients with CKD).
Selection Criteria for Studies
We included all randomized controlled trials regardless of publication status or language.
Intervention
Intravenous (IV) versus oral iron supplementation.
Outcomes Measures
Primary outcomes assessed: absolute hemoglobin (Hb) level or change in Hb level from baseline. We also assessed all-cause mortality, erythropoiesis-stimulating agent requirement, adverse events, ferritin level, and need for renal replacement therapy in patients with CKD.
Results
13 trials were identified, 6 including patients with CKD and 7 including dialysis patients. Compared with oral iron, there was a significantly greater Hb level in dialysis patients treated with IV iron (weighted mean difference, 0.83 g/dL; 95% confidence interval, 0.09 to 1.57). Meta-regression showed a positive association between Hb level increase and IV iron dose administered and a negative association with baseline Hb level. For patients with CKD, there was a small but significant difference in Hb level favoring the IV iron group (weighted mean difference, 0. 31 g/dL; 95% confidence interval, 0.09 to 0. 53). Data for all-cause mortality were sparse, and there was no difference in adverse events between the IV- and oral-treated patients.
Limitations
There was significant heterogeneity between trials. Follow-up was limited to 2 to 3 months.
Conclusions
Our review shows that patients on hemodialysis therapy have better Hb level response when treated with IV iron. For patients with CKD, this effect is small.
1Department of Nephrology and Hypertension, Tel Aviv University, Tel-Aviv, Israel
2Department of Hematology, Rabin Medical Center, Beilinson Hospital, Petah-Tikva, Israel
3Infectious Disease Unit, Rabin Medical Center, Beilinson Hospital, Petah-Tikva, Israel
4Department of Medicine E, Rabin Medical Center, Beilinson Hospital, Petah-Tikva, and the Sackler School of Medicine, Tel Aviv University, Tel-Aviv, Israel
Address correspondence to Benaya Rozen-Zvi, MD, Department of Nephrology, and Hypertension, Rabin Medical Center, Beilinson Hospital, 49100, Petah-Tikva, Israel
B.R.Z and A.G.-G. contributed equally to this work.
ABSTRACT