Use of oral moist snuff and inflammatory bowel disease.

We examined the association between oral moist snuff use and inflammatory bowel disease in a case-control study based on the population in Stockholm County. The relative risk (RR) associated with ever use of moist snuff was 2.1 (95% CI: 1.0-4.6) for Crohn's disease, and 2.2 (95% CI: 1.1-4.4) for ulcerative colitis. Cigarette smoking indicated a synergistic relation with moist snuff: the RR estimate of Crohn's disease was 3.7 (95% CI: 1.1-13.1) and of ulcerative colitis 3.3 (95% CI: 1.0-10.9) for snuff dippers who were also current cigarette smokers, but only 0.9 and 1.1 respectively for snuff dippers who had never smoked.