Association of metabolic dysfunction-associated fatty liver disease with gastrointestinal infections: insights from National Inpatient Sample Database

OBJECTIVES

The study aimed to compare the risk of gastrointestinal infections among patients with and without metabolic dysfunction-associated fatty liver disease (MAFLD).

METHODS

This was a population-based, retrospective, observational study using data from the National Inpatient Sample (NIS), the largest all-payer US inpatient care database.

SETTING

Hospitalisation of adults aged ≥18 years old admitted in 2020 was identified using the NIS. Patients were stratified by the presence and absence of MAFLD.

PARTICIPANTS

26.4 million adults aged ≥18 years old were included in the study. Patients younger than 18 and those with missing demographic or mortality data were excluded.

PRIMARY AND SECONDARY OUTCOMES

Primary outcome was to assess the overall risk of gastrointestinal infections in patients with and without MAFLD. Secondary outcomes were demographics and comorbidities stratified by the presence or absence of gastrointestinal infection, and the risk of specific gastrointestinal pathogens.

RESULTS

Of 26.4 million patients admitted in 2020, 755 910 (2.85%) had the presence of MAFLD. There was a higher prevalence of bacterial gastrointestinal infections in patients with MAFLD than those without (1.6% vs 0.9%, p<0.001). The incidence of Clostridioides difficile (1.3% vs 0.8%, p<0.001), Escherichia coli (0.3% vs 0.01%, p<0.001), and Salmonella (0.07% vs 0.03%, p<0.001) was higher in patients with MAFLD. The presence of MAFLD was associated with higher odds of developing gastrointestinal infections (adjusted OR (aOR) -1.75, 95% CI -1.68 to 1.83, p<0.001). After adjusting for confounders, results remained statistically significant (aOR -1.36, 95% CI - 1.30-1.42, p<0.001).

CONCLUSION

Even after adjusting for confounding factors, our study demonstrates an increased risk of gastrointestinal infections in patients with MAFLD, specifically of C. difficile, E. coli, and Salmonella. The immune and microbiota changes seen within MAFLD potentially contribute to the increased risk of gastrointestinal infections.

Western diet induces dysbiosis with increased E coli in CEABAC10 mice, alters host barrier function favouring AIEC colonisation

OBJECTIVE

Western diet is a risk factor for Crohn's disease (CD). Carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) is abnormally expressed in CD patients. This allows adherent-invasive Escherichia coli (AIEC) to colonise the gut mucosa and leads to inflammation. We assessed the effects of a high fat/high sugar (HF/HS) Western diet on gut microbiota composition, barrier integrity and susceptibility to infection in transgenic CEABAC10 mice expressing human CEACAMs.

DESIGN

Colonic microbiota composition and susceptibility of CEABAC10 mice to AIEC LF82 bacteria infection were determined in mice fed a conventional or HF/HS diet. Barrier function and inflammatory response were assessed by studying intestinal permeability, tight junction protein and mucin expression and localisation, and by determining histological score and levels of cytokine release.

RESULTS

HF/HS diet led to dysbiosis in WT and transgenic CEABAC10 mice, with a particular increase in E coli population in HF/HS-fed CEABAC10 mice. These mice showed decreased mucus layer thickness, increased intestinal permeability, induction of Nod2 and Tlr5 gene transcription, and increased TNFα secretion. These modifications led to a higher ability of AIEC bacteria to colonise the gut mucosa and to induce inflammation.

CONCLUSIONS

Western diet induces changes in gut microbiota composition, alters host homeostasis and promotes AIEC gut colonisation in genetically susceptible mice. These results support the multifactorial aetiology of CD and highlight the importance of diet in CD pathogenesis.