J Pediatr. 2023 May;256:113-119.e4.doi: 10.1016/j.jpeds.2022.12.016. Epub 2022 Dec 21.

Nanja Bevers ¹, Els Van de Vijver ², Arta Aliu ³, Ashkan Rezazadeh Ardabili ⁴, Philippe Rosias ³, Janneke Stapelbroek ⁵, Imke A Bertrams Maartens ⁶, Cathelijne van de Feen ⁷, Hankje Escher ⁸, Annemarie Oudshoorn ⁹, Sarah Teklenburg ¹⁰, Saskia Vande Velde ¹¹, Bjorn Winkens ¹², Maarten Raijmakers ¹³, Anita Vreugdenhil ¹⁴, Marieke J Pierik ¹⁵, Patrick F van Rheenen ¹⁶

Author information

¹Department of Paediatrics, Zuyderland Medical Center, Sittard, The Netherlands. Electronic address: n.bevers@zuyderland.nl.

²Department of Paediatric Gastroenterology, Hepatology and Nutrition, Antwerp University Hospital, Edegem, Belgium.

³Department of Paediatrics, Zuyderland Medical Center, Sittard, The Netherlands.

⁴Maastricht University Medical Center [MUMC], Department of NUTRIM, Maastricht, The Netherlands.

⁵Department of Paediatrics, Catharina Hospital, The Netherlands.

⁶Department of Paediatrics, Maxima Medical Centre, Veldhoven, The Netherlands.

⁷Department of Paediatrics, Jeroen Bosch Medical Centre, Den Bosch, The Netherlands.

⁸Erasmus Medical Center, Children's Hospital Department of Paediatric Gastroenterology, Rotterdam, The Netherlands.

⁹Department of Paediatrics, Gelre Hospital, Apeldoorn, The Netherlands.

¹⁰Department of Paediatrics, Isala Hospitals, Zwolle, The Netherlands.

¹¹Ghent University Hospital, Ghent University, Ghent, Belgium.

¹²Department of Methodology and Statistics, Maastricht University, Maastricht, The Netherlands.

¹³Laboratory of Clinical Chemistry and Haematology, Zuyderland Medical Centre, Heerlen, Limburg, The Netherlands.

¹⁴Department of Paediatrics and NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre, Maastricht, The Netherlands.

¹⁵Division of Gastroenterology-Hepatology and NUTRIM, School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre, Maastricht, The Netherlands.

¹⁶University of Groningen, University Medical Centre Groningen - Beatrix Children's Hospital, Department of Paediatric Gastroenterology Hepatology and Nutrition, Groningen, The Netherlands.

Abstract

Objective: To determine whether intravenous (IV) or oral iron suppletion is superior in improving physical fitness in anemic children with inflammatory bowel disease (IBD).

Study design: We conducted a clinical trial at 11 centers. Children aged 8-18 with IBD and anemia (defined as hemoglobin [Hb] z-score < -2) were randomly assigned to a single IV dose of ferric carboxymaltose or 12 weeks of oral ferrous fumarate. Primary end point was the change in 6-minute walking distance (6MWD) from baseline, expressed as z-score. Secondary outcome was a change in Hb z-score from baseline.

Results: We randomized 64 patients (33 IV iron and 31 oral iron) and followed them for 6 months. One month after the start of iron therapy, the 6MWD z-score of patients in the IV group had increased by 0.71 compared with -0.11 in the oral group (P = .01). At 3- and 6-month follow-ups, no significant differences in 6MWD z-scores were observed. Hb z-scores gradually increased in both groups and the rate of increase was not different between groups at 1, 3, and 6 months after initiation of iron therapy (overall P = .97).

Conclusion: In this trial involving anemic children with IBD, a single dose of IV ferric carboxymaltose was superior to oral ferrous fumarate with respect to quick improvement of physical fitness. At 3 and 6 months after initiation of therapy, no differences were discovered between oral and IV therapies. The increase of Hb over time was comparable in both treatment groups.

Trial registration: NTR4487 [Netherlands Trial Registry].