Efficacy and safety of high-dose intravenous iron in the treatment of iron-deficiency anemia in patients undergoing hemodialysis: a systematic review and meta-analysis of randomized controlled trials

Background The optimal dosing strategy for intravenous (IV) iron in patients undergoing hemodialysis (HD) with iron-deficiency anemia remains uncertain. While high-dose IV iron is commonly used, concerns exist regarding its potential risks. This systematic review and meta-analysis aims to assess the efficacy and safety of high-dose IV iron in this population. Methods PubMed, Embase, and Cochrane databases were searched for randomized controlled trials (RCTs) comparing high-dose with low-dose IV iron or no iron in patients undergoing HD with iron-deficiency anemia. Risk ratios (RR), mean differences (MD), and standardized mean differences (SMD) with 95% confidence intervals (CI) were pooled across studies. Heterogeneity was assessed using I 2 statistics. Results This analysis included five RCTs involving 2614 patients, of whom 1326 (50.7%) received high-dose IV iron. Mean follow-up ranged from 1.5 to 52.8 months. There was no significant difference between groups in the change from baseline in hemoglobin (MD 0.15 g/dL; 95% CI − 0.26 to 0.57; p = 0.47). In contrast, ferritin levels (SMD 0.98; 95% CI 0.71–1.26; p < 0.001) and transferrin saturation were significantly increased in the high-dose IV iron group compared with control (MD 5.02%; 95% CI 3.17–6.87; p < 0.001). No statistically significant differences were observed between groups for cardiac adverse events ( p = 0.064), cardiovascular mortality ( p = 0.440), vascular disorders ( p = 0.487), or infections ( p = 0.948). Conclusions High-dose IV iron demonstrated a safety profile comparable to that of low-dose or no IV iron and was associated with significant increases in transferrin saturation and ferritin levels, despite no improvements in hemoglobin levels.