P016 Smoking Status Increases Likelihood of Advanced Disease Phenotype in Crohn’s Disease

P016  Smoking Status Increases Likelihood of Advanced Disease Phenotype in Crohn’s Disease

Chattha Rimsha1, Reza Samiha2, Moradshahi Mehrshad3, Fadida Ma'ayan4, Naddaf Dezfooli Nazanin1, Chattha Zemrah5, Piracha Yasir6, Mann Ruby1, Sambhi Gagan Deep7, Samji Karina1, Narula Neeraj1
1 McMaster University, Hamilton, Canada, 2 University of Waterloo, Waterloo, Canada, 3 Western University, London, Canada, 4 University of British Columbia, Vancouver, Canada, 5 Foundation University Medical College, islamabad, Pakistan, 6 McGill University, Montreal, Canada, 7 University of Ottawa, Ottawa, Canada

BACKGROUND: The relationship between the smoking status and advanced disease phenotype (stricturing or penetrating) in patients with Crohn's disease (CD) is not well known. This study aims to determine whether smoking status increases the likelihood of advanced disease phenotype in CD patients.

METHODS: This was a retrospective study of CD patients seen at McMaster University Medical Centre, in Hamilton, ON, Canada from 2012-2020. Smoking status was dichotomized into two groups, current smokers and ex- or never smokers. Patients were classified as having the primary outcome if their gastroenterologist documented the presence of advanced disease phenotype either during the baseline assessment or during the period of follow-up. Prior knowledge in combination with forward selection was used to develop a multivariate logistic regression model and examine relationships with presence of advanced disease phenotype. The variables considered for the forward selection model included current biologic use, sex, disease duration, disease location, age at diagnosis, and presence of extraintestinal manifestations.

RESULTS: A total of 625 CD patients were included in the analysis, of which 186 had stricturing phenotype, 126 had penetrating phenotype and 313 had inflammatory phenotype only. Of the 625 CD patients, 492 had smoking status available – 67 patients were active smokers (13.6%), compared to 85 ex-smokers (17.3%) and 340 non-smokers (69.1%). A univariate regression analysis indicated that the odds ratio (OR) of advanced disease phenotype is 1.80 (95% CI, 1.06 - 3.04) for smokers compared to non/ex-smokers. In the multivariate regression analysis, current biologic use was found to have a significant relationship with advanced phenotype (OR 2.14; 95% CI, 1.47 - 3.11). After adjustment for biologic use, active smokers have 1.93 times higher odds of having advanced phenotype disease (95% CI, 1.11 - 3.35). A sub-analysis of patients with CD penetrating type only displayed smoking (OR 2.01; 95% CI, 1.14 - 3.56) and current biologic use (OR 2.06; 95% CI, 1.33 - 3.18) are significantly associated with penetrating disease. A sub-analysis of patients with CD stricturing type only did not show a significant association with smoking (OR 1.52; 95% CI, 0.88 - 2.62). However, sex [male (OR 1.62; 95% CI, 1.09 - 2.39)] and current biologic use (OR 1.61; 95% CI 1.09 - 2.38) were significantly associated with stricturing disease.

CONCLUSION(S): Current smoking is associated with increased likelihood of advanced disease phenotype in CD patients. Additionally, current biologic use and male sex were found to be have increased odds of advanced phenotype in CD patients. Patients with CD should continue to be advised on the importance of smoking cessation.