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Investigating the hygiene hypothesis as a risk factor in pediatric onset Crohn's disease: a case-control study

Devendra K Amre1, Philippe Lambrette, Liliane Law

  • 1Department of Paediatrics, University of Montreal, Quebec, Canada.

The American Journal of Gastroenterology
|April 1, 2006
PubMed

Insights

Infection exposure in early childhood may increase the risk of pediatric Crohn's disease (CD). Specific infections and day-care attendance in infancy were linked to higher CD risk in children.

Area of Science:

  • Pediatric gastroenterology
  • Immunology
  • Epidemiology

Background:

  • The hygiene hypothesis suggests reduced early-life infection exposure may increase susceptibility to immune disorders.
  • Evidence linking infection-related exposures to Crohn's disease (CD) etiology in children remains inconclusive.

Purpose of the Study:

  • To investigate the association between infection-related exposures and the risk of developing pediatric Crohn's disease (CD).

Main Methods:

  • A hospital-based case-control study was conducted with 194 newly-diagnosed pediatric CD cases and 194 matched orthopedic controls.
  • Data on infection-related exposures from birth to diagnosis were collected via questionnaires administered to mothers and subjects.
  • Multivariate conditional logistic regression analyzed the relationship between exposure timing/frequency and CD risk.

Main Results:

  • Family history of IBD, older age at diagnosis, and pet ownership were associated with increased CD risk.
  • Regular personal towel use and reduced home crowding showed protective effects against CD.
  • Early-life day-care attendance and physician-diagnosed infections between ages 5-10 years were linked to elevated CD risk.

Conclusions:

  • Infection-related exposures during childhood appear to be a significant factor in the etiology of pediatric Crohn's disease.
  • The timing of these exposures in early childhood may play a critical role in the development of pediatric CD.
Abstract

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