Malnutrition and inflammation status in nonobese patients with inflammatory bowel disease are associated with nonalcoholic fatty liver disease: a retrospective study

Background/Aims: The frequency and details of nonalcoholic fatty liver disease (NAFLD) complications in patients with inflammatory bowel disease (IBD) remain unclear. This study aimed to clarify characteristics of NAFLD in patients with IBD. Methods: We retrospectively identified and enrolled patients with IBD diagnosed with or without NAFLD by undergoing abdominal computed tomography (CT) at our institution between 2005 and 2020. The primary endpoint was the complication rate of NAFLD in patients with IBD. Secondary endpoints were the clinical characteristics of nonobese patients with IBD and comorbid NAFLD and their association with nutritional and inflammatory parameters. Results: Twenty-one (21.9%) of 96 eligible patients with IBD also had NAFLD. In nonobese patients (defined as patients with a body mass index < 25 kg/m(2)), C-reactive protein (CRP; P< 0.001) and alanine aminotransferase (P= 0.018) levels were higher and the albumin level (P= 0.005) and prognostic nutritional index (PNI; P= 0.002) values were lower in patients with NAFLD than in those without NAFLD. The PNI value was positively correlated (P< 0.001) and the CRP level was negatively correlated (P= 0.001) with the hepatosplenic ratio. However, in the NAFLD combined group, PNI (P< 0.05) and CRP values (P< 0.001) were improved over time after CT imaging by continuing IBD treatment. Conclusions: Worsening nutritional and inflammatory status in IBD patients is associated with complications of NAFLD. Diagnosis of NAFLD in IBD patients using CT imaging might be useful not only for early detection of NAFLD but also in assessing the need for therapeutic intervention for IBD.