Dr Charles Bernstein pursued potential etiological clues to Crohn's disease, and ulcerative colitis.
The investigative team conducted a population-based case control survey study.
The team included 364 cases with Crohn's disease, and 217 with ulcerative colitis, aged 18 to 50 years.
The patients were drawn from the population-based University of Manitoba Inflammatory Bowel Disease (IBD) Research Registry.
The team had 433 controls from the population-based Manitoba Health Registry by age, gender, and geographic residence matching to the cases.
Subjects were administered a multiitem questionnaire.
By univariate analysis, one of the variables predictive of Crohn's disease included lower likelihood of living on a farm.
The investigators also noted that not having drunk unpasteurized milk or eaten pork were predictive of Crohn's disease.
| Having pet cats before age 5 was protective against Crohn's disease|
|American Journal of Gastroenterology|
The team observed that patients with ulcerative colitis were less likely to have drunk unpasteurized milk and to have eaten pork.
On multivariate analysis, variables significantly associated with Crohn's disease were being Jewish, and having a first degree relative with IBD.
The investigators found ever having smoked, or living longer with a smoker was associated with Crohn's disease.
Being a first generation Canadian, having pet cats before age 5, and having larger families were protective against Crohn's disease.
For ulcerative colitis, predictive factors included being Jewish, having a relative with IBD, and ever smoking.
Dr Berstein's team commented, “This study reinforced the increased risk associated with family history, being Jewish, and smoking history.”
“However, a number of significant associations with Crohn's disease and ulcerative colitis on univariate and multivariate analysis may support the ‘hygiene hypothesis' and warrant further exploration in prospective studies.”