Iron-Deficiency and Anemia Prevalent, Undermanaged in Patients With IBD

Patients with IBD have a higher risk for developing anemia due to iron deficiency, resulting from chronic gastrointestinal blood loss, nutritional deficiencies from malabsorption or malnutrition, and inflammation.

Iron deficiency and anemia are prevalent and suboptimally managed among patients with inflammatory bowel disease (IBD), especially those with evidence of active biochemical inflammation, according to study findings published in Journal of Clinical Medicine.

Researchers conducted a national, multicenter, cross-sectional study from January to November of 2021 across 16 academic teaching hospitals in the Netherlands. They assessed the prevalence of anemia and iron deficiency among 2197 adult outpatients with IBD. Among the study population, 1271 had Crohn disease (CD), 849 had ulcerative colitis (UC), and 77 had unclassified IBD diagnoses.

Overall, 18% of the study participants with IBD had anemia, and 7.1% of these patients had severe anemia. Type of IBD diagnosis did not influence anemia prevalence; however, biological sex did. Men demonstrated a significantly higher prevalence of anemia than women (22.8% vs. 14.5%; P <.001).

The medical records for only 59.3% of the participants had sufficient information on iron levels and biochemical inflammation. Approximately 43.4% of those with available iron data demonstrated iron deficiency with no observable difference between those with CD or UC.

[B]iochemical inflammation is a major risk factor for anemia and ID, but it is seldom taken into consideration when prescribing iron therapy.

In contrast with anemia, women demonstrated an approximately 2-fold higher prevalence of iron deficiency than men (51.8% vs 31.5%; odds ratio [OR], 2.63; 95% CI, 1.84-3.75; P <.001). Patients with evidence of biochemical inflammation exhibited a higher prevalence of iron deficiency than those without biochemically active inflammation (70.8% vs. 23.9%; P <.001).

Neither biological sex nor IBD diagnosis type influenced the prevalence of iron-deficient anemia (IDA), defined as concurrent anemia and iron deficiency.

Researchers then assessed 112 physicians and their management of iron deficiency and anemia among patients with IBD with 61.6% responding to the questionnaire. They observed that 89.7% of respondents prescribed standard doses of intravenous or oral iron to treat symptomatic anemia regardless of severity in active or quiescent IBD, respectively.

In contrast, only 22% of respondents prescribed treatment for nonanemic iron deficiency, regardless of symptoms, and one-fourth of respondents did not treat iron deficiency at all.

Limitations of the study include the cross-sectional design, missing data, and lack of full characterization of iron deficiency across the entire cohort. The researchers also did not account for current IBD therapies such as thiopurines, corticosteroids, biologicals, proton-pump inhibitors, blood transfusions, or erythropoietin-stimulating agents, which may have influenced the results.

Study authors conclude, “[T]his study shows that anemia and ID remain highly prevalent in patients with IBD under ambulatory care.” They add, “[B]iochemical inflammation is a major risk factor for anemia and ID, but it is seldom taken into consideration when prescribing iron therapy.”

Disclosures: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.


Loveikyte R, Boer M, van der Meulen CN, et al. Anemia and iron deficiency in outpatients with inflammatory bowel disease: ubiquitous yet suboptimally managed. J Clin Med. 2022;11(22):6843. doi:10.3390/jcm11226843