This systematic review and meta-analysis of 9 randomized controlled trials (973 patients) compared any treatment for anemia in patients with inflammatory bowel disease (IBD). Meta-analyses were performed for intravenous (IV) versus oral iron and for erythropoiesis-stimulating agents (ESAs) versus placebo. As expected, IV iron was associated with a higher likelihood of achieving a Hb response in comparison to oral iron, with a decrease in adverse events requiring discontinuation of intervention and without an increase in serious adverse events. C-reactive protein (CRP) levels and disease activity indices were not significantly affected by IV iron.

The authors conclude that treatment for anemia in IBD should include IV iron rather than oral iron replacement, due to improved Hb response, no added toxicity and no negative effect on disease activity. However, this conclusion is not fully supported by others who consider that there is still a place for low-dose oral iron in those with milder anemia and/or lower disease activity (Reinisch W et al, J Crohns Colitis 2013;7:429-40; Rizvi S & Schoen RE, Am J Gastroenterol 2011;106:1872-9).

Overall, although this meta-analysis includes more studies, as they are heterogeneous with respect to iron dose, administration schedule, and follow-up duration, it does not appear to add much to what is already known: the superior efficacy and lower rate of treatment discontinuation with IV iron (Goldberg ND, Clin Exp Gastroenterol 2013;6:61-70; Gomollón F & Gisbert JP, Curr Opin Gastroenterol 2013;29:201-7; Lee TW et al, J Crohns Colitis 2012;6:267-75; Muñoz M et al, World J Gastroenterol 2009;15:4666-74).

– Manuel Muñoz