Efficacy of iron supplementation in patients with inflammatory bowel disease treated with anti-tumor necrosis factor-alpha agents

Background: Anemia is a common extraintestinal manifestation of inflammatory bowel disease (IBD). However, data on the influence of anti-tumor necrosis factor-alpha (anti-TNF-alpha) agents and iron supplementation on anemia in patients with IBD are sparse. We assessed the effect of iron supplementation in patients with IBD initially treated with an anti-TNF-alpha agent. Methods: Data from 79 IBD patients who started anti-TNF-alpha treatment at a tertiary hospital were analyzed. The patients were divided into the anti-TNF-alpha (n = 52) and anti-TNF-alpha with iron supplementation (n = 27) groups. Effects on laboratory parameters, the prevalence of anemia, and disease activity were evaluated at baseline (year 0) and 1 year later. Results: The hemoglobin (Hb) level significantly increased between years 0 and 1 in both groups [12.0 +/- 1.8-13.3 +/- 2.0 g/dL in the anti-TNF-alpha group (p < 0.001) and 9.8 +/- 2.4-11.7 +/- 2.3 g/dL in the anti-TNF-alpha and iron supplementation group (p = 0.004)]. In a subgroup analysis of severely anemic patients with IBD, iron supplementation increased the magnitude of the improvement in Hb level (8.5 +/- 1.5-11.4 +/- 2.1 g/dL;p = 0.001) compared with the anti-TNF-alpha group (9.3 +/- 0.8-11.4 +/- 2.7 g/dL;p = 0.081). Disease activity was significantly improved in both groups at year 1 compared with year 0. Persistent anemia was significantly correlated with severe anemia at baseline (p = 0.017). Conclusion: In anemic patients with IBD, anti-TNF-alpha agents led to clinically meaningful improvements in anemia independent of iron supplementation. Also, iron supplementation could be helpful in severely anemic patients with IBD.