Influence of nonalcoholic fatty liver disease on inflammatory bowel disease hospitalizations in the United States

BACKGROUND: The reported prevalence of nonalcoholic fatty liver disease (NAFLD) in patients with inflammatory bowel disease (IBD) is 32%. We assessed the influence of NAFLD on IBD hospitalizations in the United States (US). METHODS: We utilized the National Inpatient Sample database, from 2016-2019, to identify the total IBD hospitalizations in the US and we further subdivided them according to the presence or absence of NAFLD. Hospitalization characteristics, comorbidities and outcomes were compared. Statistical significance was set at P<0.05. RESULTS: There were 1,272,260 IBD hospitalizations in the US, of which 5.04% involved NAFLD. For IBD hospitalizations with NAFLD, the mean age was 50-64 years, and the proportion of males was 46.97%. IBD hospitalizations with NAFLD had a lower proportion of African Americans (8.7% vs. 11.38%, P<0.001). Comorbidities such as hypertension (50.34% vs. 44.04%, P<0.001) and obesity (18.77% vs. 11.81%, P<0.001) were significantly higher in the NAFLD cohort. Overall, based on the Charlson Comorbidity Index, patients with NAFLD had a higher number of comorbidities (52.77% vs. 20.66%, P<0.001). Mortality was higher in the NAFLD compared to the non-NAFLD cohort (3.14% vs. 1.44%, P<0.001). Patients with NAFLD also incurred significantly higher hospital charges ($69,536 vs. $55,467, p<0.001) and had a longer mean length of stay (6.10 vs. 5.27 days, P<0.001) compared to the cohort without NAFLD. Complications and inpatient procedure requirements were also higher in the NAFLD cohort. CONCLUSION: Our study revealed greater mortality, morbidity, and healthcare resource utilization in patients with IBD who were hospitalized with a concomitant diagnosis of NAFLD.