Real-world study supports high-dose IV iron for IBD-associated anaemia

Real-world evidence shows the efficacy and safety of high-dose intravenous (IV) iron for the treatment of anaemia in individuals with inflammatory bowel disease (IBD), irrespective of inflammatory activity.

A group of investigators from Hessen, Germany, evaluated 421 patients with Crohn’s disease or ulcerative colitis who received IV iron substitution. Of these, 197 were treated with iron isomaltoside and 224 with ferric carboxymaltose. The mean cumulative dose was approximately 1,200 mg over 12–16 weeks.

The variables evaluated were haematologic response (≥2 g/dL haemoglobin increase), iron parameters, C-reactive protein (CRP), clinical disease activity indices (CDAI/CAI*), and patient-reported IBD-related symptoms (ie, fatigue, impaired concentration, headache, pallor, hair loss, exertional dyspnoea, sleep disorders, restless legs syndrome). Participants were stratified by baseline CRP (<5, 5–10, or >10 mg/L). [AIBD 2025, abstract 135]

Haemoglobin increased significantly from 10.7 to 13.1 g/dL. Fifty-seven percent of participants had a ≥2-g/dL improvement in haemoglobin.

Ferritin also increased by approximately 96 µg/L, as did transferrin saturation (from 8.1 percent to 24 percent).

There was a substantial reduction in CRP during treatment (from 6.4 to 3.5 mg/L on average), with the most pronounced effect observed in patients with baseline CRP >5 mg/L. “IV iron efficacy was independent of baseline CRP levels,” the researchers noted.

CDAI/CAI and IBD-related symptoms improved consistently, regardless of disease type, inflammatory activity, or concomitant immunosuppressive or biologic therapy. There was no evidence of worsening of disease activity, they added.

A common IBD complication

Iron-deficiency anaemia (IDA) is a common IBD complication resulting from chronic blood loss and impaired iron absorption secondary to chronic tissue inflammation. Given the lack of signs and symptoms of iron deficiency, regular monitoring of haemoglobin levels in patients with IBD is imperative for early detection of anaemia. IDA in IBD is tied to poor quality of life, hence the need for prompt diagnosis and appropriate treatment. [World J Gastrointest Pathophysiol 2015;6:62-72]

Oral iron preparations, which are inexpensive and convenient, are used in patients with mild disease activity. However, these can trigger gastrointestinal side effects, such as abdominal pain and diarrhoea, which limit their use and patient adherence. [World J Gastrointest Pathophysiol 2015;6:62-72]

Guidelines recommend IV iron as a first-choice treatment for IDA in active IBD (elevated CRP levels and/or clinically active IBD), if haemoglobin level is <10 g/dL, or in case of prior intolerance to iron supplementation. However, concerns remain about its use in individuals with high inflammatory activity. Moreover, IV iron is more expensive than oral formulations, more difficult to administer daily, and carries the risk of iron overload, anaphylaxis, or hypophosphataemia. [Front Med (Lausanne) 2021;doi:10.3389/fmed.2021.686778]

“We combined real-world data from two large German multicentre studies to assess the efficacy and safety of high-dose IV iron in patients with IBD, with special emphasis on inflammation,” the researchers said. “We found that high-dose IV iron therapy is effective, safe, and well-tolerated in individuals with IBD, even in the presence of active inflammation.”

“Not only does it correct IDA, but high-dose IV iron therapy is inflammation-neutral and associated with significant improvements in CRP, disease activity indices, and patient-reported symptoms,” they added. “These underscore the value of high-dose IV iron as standard care in IBD-associated anaemia.”