The prevalence of anemia and iron deficiency in IBD outpatients in Scandinavia

Objective. To evaluate the prevalence of anemia and iron deficiency (ID) among patients with inflammatory bowel disease (IBD) in the Scandinavian countries. Material and methods. A cross-sectional study including 429 IBD patients from six centers in Denmark, Norway and Sweden. Patients were screened for anemia and ID. Each center included similar to 5% of their IBD cohort. Patients were consecutively seen in the outpatient clinic, regardless of disease activity and whether the visits were scheduled or not. Results. The overall prevalence of anemia was 19% (95% CI: 16--23%). The prevalence was higher among patients with Crohn's disease than among patients with ulcerative colitis (p = 0.01). The etiology of anemia was as follows: iron deficiency anemia (20%), anemia of chronic disease (12%), and both conditions (68%). Less than 5% had folate acid or vitamin B12 deficiency. ID was found in 35% (CI: 31-40%) of the patients. Conclusions. Anemia was present in every fifth IBD patient and ID in every third IBD patient.