Exploring the Effects of Cigarette Smoking on Inflammatory Bowel Disease Using Mendelian Randomization.
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ABSTRACT: Background
Previous observational evidence has suggested an association between smoking and inflammatory bowel disease (IBD).Methods
We used observational techniques followed by Mendelian randomization to explore whether smoking is a causal factor in the development of IBD and its subtypes.Results
In those who have ever smoked, we observed increased risk of IBD and, in current smokers, we observed increased risk of Crohn disease and decreased risk of ulcerative colitis. However, our Mendelian randomization analyses found little evidence that smoking affects the development of IBD.Conclusion
Overall, our results suggest that smoking does not causally influence the risk of IBD.
SUBMITTER: Jones DP
PROVIDER: S-EPMC7809707 | biostudies-literature | 2020 Jan
REPOSITORIES: biostudies-literature
Publications
Exploring the Effects of Cigarette Smoking on Inflammatory Bowel Disease Using Mendelian Randomization.
Jones Daniel P DP Richardson Tom G TG Davey Smith George G Gunnell David D Munafò Marcus R MR Wootton Robyn E RE
Crohn's & colitis 360 20200101 1
<h4>Background</h4>Previous observational evidence has suggested an association between smoking and inflammatory bowel disease (IBD).<h4>Methods</h4>We used observational techniques followed by Mendelian randomization to explore whether smoking is a causal factor in the development of IBD and its subtypes.<h4>Results</h4>In those who have ever smoked, we observed increased risk of IBD and, in current smokers, we observed increased risk of Crohn disease and decreased risk of ulcerative colitis. H ...[more]
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