Impact of tobacco use on inpatient outcomes in inflammatory bowel disease: a retrospective matched cohort study

Background: Tobacco plays a complex role in patients with inflammatory bowel disease (IBD). Its impact on inpatient outcomes of IBD needs additional study. We aimed to assess the impact of smoking on clinical outcomes in hospitalized patients with IBD. 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 utilizing ICD-10 codes. Patients were stratified according to the smoking status in two groups. A propensity score matching was utilized to balance comorbidities between study groups. Study outcomes included rates of steroid use, surgeries, gastrointestinal (GI) bleeding, perianal abscess, and overall mortality. All outcomes were assessed during the index hospitalization. Statistical analysis was performed using Stata 17 software. Results were reported as adjusted odds ratios (aORs) with 95% confidence intervals (CIs). 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 =0.54, 95% CI: 0.32-0.96, P=0.03). For CD patients, smokers had higher odds of steroid use (aOR =1.13, 95% CI: 1.03-1.25, P=0.009), perianal abscess (aOR =1.12, 95% CI: 1.10-1.36, P=0.02), and all-cause mortality (aOR =1.51, 95% CI: 1.27-1.84, P=0.04). All other outcomes were not significant between the study cohorts. Conclusions: Tobacco use in hospitalized patients with UC was associated with lower steroid use, while in patients with CD, it correlated with higher steroid use and increased odds of perianal abscesses. These findings highlight the complex impact of tobacco use on IBD outcomes.