Meta-analysis of the efficacy of intravenous iron supplementation versus oral iron supplementation on anemia in patients with non-dialysis-dependent chronic kidney disease

Objective To evaluate the efficacy of intravenous iron supplementation versus oral iron supplementation on anemia in patients with non-dialysis-dependent chronic kidney disease (ND-CKD) by the method of systematic evaluation. Methods By computer and manual search until December 1, 2017, the EMBASE, PUBMED, and Cochrane Library were searched for all the randomized controlled trials (RCT) on the efficacy of intravenous iron supplementation or oral iron supplementation for anemia patients with ND-CKD. Statistical analyses were conducted with the RevMan Version 5 software for meta-analysis. Results A total of 11 foreign language RCT studies were included, totaling 1 707 patients, including 852 cases of intravenous iron supplementation and 855 cases of oral iron supplementation. The results of the analyses showed that the intravenous iron supplementation significantly increased the levels of hemoglobin (WMD 0.39 g/dl, 95%CI 0.26-0.52, P<0.0001), transferrin saturation (TSAT) (WMD 3.97%, 95%CI 2.24-5.7, P<0.0001), and ferritin (WMD, 244.51 ng/ml, 95%CI 185.51-303.52, P<0.0001), compared with oral iron supplementation. There was no significant difference in the incidence of adverse events between the two iron supplementation methods (RR 0.79, 95%CI 0.44-1.44, P=0.45). Conclusion The intravenous iron supplementation method was more effective in treating anemia patients with ND-CKD than the oral iron supplementation method. Key words: Oral iron supplementation; Intravenous iron supplementation; Anemia; Non-dialysis-dependent chronic kidney disease; Meta-analysis