Institutional members access full text with Ovid®

Share this article on:

Prevalence of Anemia in Inflammatory Bowel Diseases in European Countries: A Systematic Review and Individual Patient Data Meta-analysis

Filmann, Natalie Dipl Math*; Rey, Julia Dipl Math*; Schneeweiss, Sven MD; Ardizzone, Sandro MD; Bager, Palle MPH§; Bergamaschi, Gaetano MD; Koutroubakis, Ioannis MD; Lindgren, Stefan MD, PhD**; Morena, Felipe de la MD††; Moum, Bjørn MD‡‡; Vavricka, Stephan R. MD§§; Schröder, Oliver MD; Herrmann, Eva PhD*; Blumenstein, Irina MD

doi: 10.1097/01.MIB.0000442728.74340.fd
Clinical Review Articles

Background: The main objective is to determine the overall prevalence of anemia in inflammatory bowel diseases (IBD) in Europe.

Methods: A systematic literature search in PubMed and Embase was performed for studies published between January 2007 and May 2012. Eligible studies were included if they were original full-paper publications originated from Europe and if the authors agreed to provide their data. An overall prevalence of anemia in IBD, disease specific, and age–gender stratified basis prevalences were estimated. The influence of disease entity (Crohn's disease/ulcerative colitis), gender, age, disease activity (remission/active disease), and IBD-specific treatment strategies on the prevalence of anemia was analyzed by a mixed logistic regression model. Thereby, the factor country of origin was included as a random effect.

Results: Data were available for 2192 patients, mainly treated in tertiary referral centers. The overall prevalence of anemia in IBD patients was 24% (95% confidence interval, 18–31). Age–gender stratified prevalences were estimated for the age strata 18 to 29, 30 to 39, 40 to 49, 50 to 64, 65 to 74, >74 years and ranged from 18% to 35%. Patients receiving IBD-specific medication (P = 0.0002, odds ratio 1.54), and patients with active disease status (P < 0.0001, odds ratio 2.72) were significantly more likely to have anemia compared with patients not receiving IBD-specific medication or being in remission. Patients with ulcerative colitis tended to have anemia less likely than patients with Crohn's disease (P = 0.01, odds ratio 0.77).

Conclusions: The overall prevalence of anemia in patients with Crohn's disease was 27% (95% confidence interval, 19–35) and 21% (95% confidence interval, 15–27) in patients with ulcerative colitis. Thereby, 57% of the anemic patients were iron deficient.

Article first Published online 25 February 2014Supplemental Digital Content is Available in the Text.

*Institute of Biostatistics and Mathematical Modeling, Faculty of Medicine, and

Department of Internal Medicine 1, Goethe-University Hospital, Frankfurt, Germany;

IBD Unit, Chair of Gastroenterology, L. Sacco University Hospital, Milan, Italy;

§Department of Medicine V (Hepatology and Gastroenterology), Aarhus University Hospital, Aarhus, Denmark;

Dip. Area Medica: Medicina Generale 1, Policlinico San Matteo, Pavia, Italy;

Department of Gastroenterology, University Hospital Heraklion, Crete, Greece;

**Department of Gastroenterology, University Hospital Skane, Malmö, Sweden;

††Sección de Aparato Digestivo, Hospital Infanta Cristina, Parla, Madrid, Spain;

‡‡Department of Gastroenterology, Oslo University Hospital, Oslo, Norway; and

§§Division of Gastroenterology, Triemli Hospital, Zurich, Switzerland.

Reprints: Natalie Filmann, Dipl Math, Goethe-University, Hospital, Theodor-Stern-Kai 7, 60590 Frankfurt, Germany (e-mail:

Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's Web site (

N. Filmann and J. Rey contributed equally to the article.

The authors have no relevant conflicts of interest to disclose.

Received December 09, 2013

Accepted December 24, 2013

© Crohn's & Colitis Foundation of America, Inc.
You currently do not have access to this article

To access this article:

Note: If your society membership provides full-access, you may need to login on your society website