Original Contribution
The American Journal of Gastroenterology (2006) 101, 993–1002; doi:10.1111/j.1572-0241.2006.00381.x
A Population-Based Case Control Study of Potential Risk Factors for IBD
Charles N Bernstein MD1,2, Patricia Rawsthorne RN1,2, Mary Cheang MMath4 and James F Blanchard MD, PhD1,3
- 1University of Manitoba Inflammatory Bowel Disease Clinical and Research Centre, University of Manitoba, Winnipeg, Manitoba, Canada
- 2Departments of Internal Medicine, University of Manitoba, Winnipeg, Manitoba, Canada
- 3Departments of Community Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
- 4Community Health Sciences Biostatistical Consulting Unit, University of Manitoba, Winnipeg, Manitoba, Canada
Correspondence: Charles N Bernstein, MD, University of Manitoba, Section of Gastroenterology, 804F-715 McDermot Avenue, Winnipeg, MB, Canada R3E3P4.
Received 12 August 2005; Accepted 17 September 2005.
Abstract
BACKGROUND:
We aimed to pursue potential etiological clues to Crohn's disease (CD) and ulcerative colitis (UC) through a population-based case control survey study.
METHODS:
Cases with CD (n = 364) and UC (n = 217), ages 18–50 yr were drawn from the population-based University of Manitoba IBD Research Registry. Potential control subjects were drawn from the population-based Manitoba Health Registry by age, gender, and geographic residence matching to the cases (n = 433). Subjects were administered a multiitem questionnaire.
RESULTS:
By univariate analysis, some of the variables predictive of CD included lower likelihood of living on a farm, of having drunk unpasteurized milk or having eaten pork, and UC patients were less likely to have drunk unpasteurized milk and to have eaten pork. On multivariate analysis, variables significantly associated with CD were being Jewish (OR = 4.32, 95% CI 1.10–16.9), having a first degree relative with IBD (OR = 3.07, 95% CI 1.73–5.46), ever having smoked (OR = 1.54, 95% CI, 1.06–2.25), living longer with a smoker (OR = 1.03, 95% CI, 1.01–1.04). Being a first generation Canadian (OR = 0.33, 95% CI, 0.17–0.62), having pet cats before age 5 (OR = 0.66, 95% CI, 0.46–0.96) and having larger families (OR = 0.87, 95% CI, 0.79–0.96) were protective against CD. For UC being Jewish (OR = 7.46, 95% CI, 2.33–23.89), having a relative with IBD (OR = 2.23, 95% CI, 1.27–3.9), and ever smoking (OR = 1.62, 95% CI, 1.14–2.32) were predictive.
CONCLUSION:
This study reinforced the increased risk associated with family history, being Jewish, and smoking history, however, a number of significant associations with CD and UC on univariate and multivariate analysis may support the "hygiene hypothesis" and warrant further exploration in prospective studies.
