METHODS: A literature search was performed using MEDLINE, Embase and the Cochrane Collaboration Central Register of Clinical Trials from inception until December 2014, to identify randomized controlled trials of intravenous iron and ESA, in patients undergoing haemodialysis for end-stage kidney disease. Dosing of IV iron in concordance with the Kidney Disease Improving Global Outcomes guidelines was considered optimal iron therapy.

RESULTS: Of the 28 randomized controlled trials identified, seven met the criteria for inclusion in the meta-analysis. Results of random-effects meta-analysis show a statistically significant weighted mean (95% CI) difference of -1733 [-3073, -392] units/week in ESA dose for optimal iron versus suboptimal iron. The weighted average change in ESA dose was a reduction of 23% (range -7% to -55%) attributable to appropriate dosing of intravenous iron. A comparison of intravenous iron versus oral iron/no iron (five trials) showed a greater reduction in ESA dose, although this did not reach statistical significance (weighted mean difference, 95% CI: -2,433 [-5183, 318] units/week). The weighted average change in ESA dose across the five trials was a reduction of 31% (range -8% to -55%).