Epidemiology of Inflammatory Bowel Disease: Is There a Shift Towards Onset at a Younger Age?

Braegger, Christian P.*; Ballabeni, Pierluigi; Rogler, Daniela*; Vavricka, Stephan R.; Friedt, Michael*; Pittet, Valérie; the Swiss IBD Cohort Study Group

Journal of Pediatric Gastroenterology & Nutrition: August 2011 - Volume 53 - Issue 2 - p 141–144
doi: 10.1097/MPG.0b013e318218be35
Original Articles: Gastroenterology

Objectives: Increasing numbers of paediatric and adolescent patients with Crohn disease (CD) and ulcerative colitis (UC) are reported. To determine whether this observation is a consequence of a shift towards onset at a younger age, we analysed retrospective data from patients enrolled in the Swiss IBD Cohort Study (SIBDCS).

Patients and Methods: The SIBDCS is a disease-based cohort in Switzerland, which collects retrospective and prospective data on a large sample of patients with inflammatory bowel disease (IBD). Patients, diagnosed from 1980, were stratified according to diagnosis of CD and UC. Age at disease onset (age at first symptoms and age at diagnosis) was analysed in relation to calendar year of disease onset. Data were extracted from physician and patient questionnaires. Linear regressions of age at disease onset by calendar year of disease onset adjusted by sex, country of birth, and education were performed.

Results: Adjusted regression coefficients for CD and UC were significantly positive, that is, age at disease onset has increased with time. Male sex was associated with an increase in age at disease onset, and birth in Switzerland with a decrease. These associations were statistically significant.

Conclusions: The results from the SIBDCS do not support the hypothesis that disease onset of both CD and UC occur today at a younger age. On the contrary, our results show that there is a significant trend for age at disease onset occurring at an older age today as compared with recent decades. We conclude that the observation of increasing numbers of paediatric and adolescent patients with IBD is not caused by a trend towards disease onset at a younger age, but that this may rather be a consequence of the overall increasing incidence of these conditions.

*Division of Gastroenterology and Nutrition, University Children's Hospital Zurich

Healthcare Evaluation Unit, Institute of Social and Preventive Medicine (IUMSP), Centre Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne

Division of Gastroenterology, University Hospital Zurich, Switzerland.

Address correspondence and reprint requests to Prof Christian P. Braegger, Division of Gastroenterology and Nutrition, University Children's Hospital, Steinwiesstrasse 75, CH-8032 Zurich, Switzerland (e-mail: christian.braegger@kispi.uzh.ch).

Received 12 May, 2010

Accepted 22 February, 2011

Members of the Swiss IBD Cohort Study Group: Pierluigi Ballabeni, Peter Bauerfeind, Christoph Beglinger, Stefan Begré, José Bengoa, Janek Binek, Daniel Boller, Jan Borovicka, Christian Braegger, Patrick Bühr, Patrick Brun, Bernard Burnand, Rafael Camara, Dominique Criblez, Philippe de Saussure, Lukas Degen, Joakim Delarive, Tobias Ehmann, Matthias Engelmann, Ali El Wafa, Christian Felley, Alain Frei, Remus Frei, Michael Fried, Michael Friedt, Florian Froehlich, Suzanne Gallot-Lavallée, Tilman Gerlach, Martin Geyer, Marc Girardin, Oliver Goetze, Horst Haack, Serger Hediger, Peter Hengstler, Klaas Heyland, Patrick Janiak, Pascal Juillerat, Vera Kessler Brondolo, Christoph Knoblauch, Gerd A. Kullak-Ublick, Michael Manz, Rémy Meier, Christa Meyenberger, Pierre Michetti, Christian Mottet, Christoph Müller, Beat Müllhaupt, Thierry Nicolet, Andreas Nydegger, Isabelle Pache, Franziska Piccoli, Julia Pilz, Valérie Pittet, Ronald Rentsch, Jean-Pierre Rey, Silvia Rihs, Daniela Rogler, Gerhard Rogler, Markus Sagmeister, Bernhard Sauter, Michela Schäppi, Niklaus Schaub, Susanne Schibli, Alain Schoepfer, Franck Seibold, Johannes Spalinger, Philippe Stadler, Michael Steuerwald, Alex Straumann, Michael Sulz, Joël Thorens, John-Paul Vader, Stefan Vavricka, Jürg Vögtlin, Roland Von Känel, Gert Wachter, Jürg Wermuth, Paul Wiesel.

This work was funded by a research grant from the Swiss National Science Foundation (grant no. 3347CO-108792 Swiss IBD Cohort). S.R.V. acknowledges additional research support from the Swiss National Science Foundation (320000-114009/1) and a grant from the Zurich Centre of Integrative Human Physiology.

The authors report no conflicts of interest.

Copyright 2011 by ESPGHAN and NASPGHAN