Iron replacement therapy in inflammatory bowel disease patients with iron deficiency anemia: a systematic review and meta-analysis.

BACKGROUND AND AIMS Iron deficiency anemia (IDA) is a common problem in patients with Inflammatory Bowel Disease (IBD) and has a significant negative impact on quality of life. The aim was to compare the clinical efficacy of intravenous (IV) versus oral (PO) iron replacement in adult IBD with iron deficiency anemia (IDA). METHODS A systematic search for randomized controlled trials comparing the efficacy of IV versus PO iron therapy in the treatment of IDA in adult IBD patients. The primary outcome was the mean change in the hemoglobin at the end of study and secondary outcomes include mean change in ferritin, clinical disease activity index, quality of life score and the adverse reaction rate. RESULTS The search strategy identified 757 articles while only three industry-funded articles met the inclusion criteria for systematic review and meta-analysis. The total sample size was 333 patients with 203 patients receiving IV therapy. IV route was associated with a 6.8 g/L higher mean hemoglobin increment and 110 μg/L higher mean ferritin increment. The IBD activity index and Quality of Life scores were comparable between the two treatment groups. More adverse events were reported in the oral treatment group with the odds for discontinuation being 6.2 (CI 2.2, 17.1). CONCLUSIONS Intravenous iron treatment is better tolerated and more effective than oral iron treatment in improving ferritin. The higher hemoglobin gain with the IV route was small and of uncertain clinical significance. The combined sample size of the included studies was small and further clinical trials are required.