S1516 Impact of Tobacco Use in Patients With Inflammatory Bowel Disease: Nationwide Propensity-Matched Analysis

Introduction: Smoking has been shown to be an influential factor in patients with inflammatory bowel diseases (IBD), including ulcerative colitis (UC) and Crohn’s disease (CD). However, its impact on inpatient outcomes of IBD remains unclear. In this study, we aim to assess the effects of smoking on clinical outcomes in patients with UC and CD, using a large inpatient dataset. Methods: We conducted a retrospective cohort study using data from the National Inpatient Sample (NIS) spanning from 2016 to 2019. Patients with UC and CD were identified using International Classification of Diseases-10 codes. Then, they were stratified according to the smoking status. A propensity score matching was utilized to balance relevant comorbidities between each group. Outcomes of interest included steroid use, surgeries, gastrointestinal (GI) bleeding, perianal abscess, and mortality. Statistical analysis was performed using Stata 17. Chi-square (for categorical variables), and t-tests (for continuous variables) were used to compare the baseline characteristics between the study groups. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to compare the outcomes during the hospitalization. Results: A total of 413,208 patients were included in our study, 180,558 patients had UC, and 232,650 patients had CD. After propensity-score matching, we had a total of 151,106 patients: 39,616 patients had UC, with a total of 19,808 in each group. The CD patients were 111,490, with a total of 55,745 patients in each group. For UC patients, smokers had lower odds of steroid use (aOR = 0.69, 95% CI = [0.61-0.79], P = 0.001), and all-cause mortality (aOR = 0.69, 95% CI = [0.3-0.96], P = 0.032). For CD patients, they had higher odds of steroid use (aOR = 1.13, 95% CI = [1.03-1.25], P = 0.009), and perianal abscess (aOR = 1.12, 95% CI = [1.10-1.36], P = 0.001). CD smokers recorded lower odds of all-cause mortality (aOR = 0.51, 95% CI = [0.27-0.98], P = 0.04). All other outcomes were non-statistically significant between the study cohorts. Conclusion: Smoking in hospitalized UC patients was associated with lower steroid use, while in CD patients, it correlated with higher steroid use and increased odds of perianal abscess. These findings highlight the complex impact of smoking on IBD outcomes, warranting further investigation into its clinical implications.