S1636 Prevalence and Impact of MAFLD/NAFLD on Inpatient Outcomes in Patients With Inflammatory Bowel Disease: A Propensity Score-Matched Nationwide Analysis

Introduction: Inflammatory bowel disease (IBD) patients exhibit increased metabolic dysfunction-associated fatty liver disease (MAFLD) or Non-alcoholic fatty liver disease (NAFLD) prevalence. To assess the national prevalence of NAFLD in hospitalized IBD patients and its association with mortality, complications, length of stay (LOS), and hospital charges. Methods: Adult hospitalizations from the National Inpatient Sample from 2018 to 2021 were retrospectively analyzed. Patients with NAFLD or IBD were identified using International Classification of Diseases-10 codes. NAFLD prevalence was compared between IBD and non-IBD groups. Patients with IBD were stratified by the presence of NAFLD. Baseline characteristics were compared between the presence or absence of NAFLD in patients with IBD. Propensity score matching was performed to control for baseline differences. Inpatient outcomes were then compared between matched groups. P-values for secondary outcomes were adjusted using the Benjamini-Hochberg method, with statistical significance defined as P < 0.05. Results: We identified 254,032 hospitalized patients with diagnosis of IBD. The prevalence of NAFLD was significantly higher among patients with IBD (5.42%) compared to those without IBD (3.55%; P < 0.001). Prior to matching, notable baseline differences existed between IBD patients with NAFLD (n = 13,813) and those without. In the matched cohort (N ≈ 27,624), baseline differences were not significant. NAFLD was independently associated with worse inpatient outcomes. It was linked to longer hospital stay (mean difference [MD]: 0.39 days; adjusted P < 0.001) and higher total hospital charges (MD: $7,130; adjusted P < 0.001). NAFLD was also associated with increased odds of inpatient mortality (OR 1.58), acute kidney injury (OR 1.14), intestinal obstruction (OR 1.29), and gastrointestinal bleeding (OR 1.30), all statistically significant after false discovery rate adjustment (P < 0.001). Conversely, NAFLD was linked to lower odds of colectomy (OR 0.75, adjusted P < 0.001), intestinal perforation (OR 0.71, adjusted P = 0.006), and peritonitis (OR 0.78, adjusted P = 0.007). Conclusion: NAFLD is significantly more prevalent among hospitalized patients with IBD and is independently associated with adverse inpatient outcomes, including higher mortality, greater complication rates, prolonged hospital stay, and increased healthcare costs. These findings underscore the importance of early recognition and multidisciplinary management of NAFLD in the IBD population.