Prevalence and Predictors of Non-Alcoholic Liver Disease on MRI Among Patients with Crohn's Disease

Background: It has been documented that Crohn’s disease patients were prone to develop non-alcoholic liver fatty liver disease with less metabolic factors. Our purpose is to investigate the prevalence, clinical characteristics and possible indicators for NAFLD in a cohort of Chinese patients with Crohn’s disease. Methods: : Established Crohn’s disease (CD) patients who underwent magnetic resonance enterography (MRE) at the gastroenterology unit of our hospital were consecutively enrolled between June 2018 to May 2020. The diagnosis of NAFLD was made by magnetic resonance proton density fat fraction (MR-PDFF) maps. Medical records during hospitalization were collected and examined by univariate and multivariate analyses. Then a predictive model was constructed based on logistic regression analysis to evaluate the risk of developing NAFLD. Results: : A total of 340 CD subjects were enrolled in this study, 83 (24.4%) suffered from NAFLD. Compared with those without NAFLD, patients with NAFLD showed longer disease duration, higher BMI, more frequent use of corticosteroid and pronouncedly elevated liver function tests. The comparison showed no difference in terms of prolonged anti TNF-α use (>54w). Multivariate analysis demonstrated that BMI, ALT, AST and GGT could independently predict hepatic steatosis. Conclusion: NAFLD is frequent in chronic CD patients, while long term use of anti TNF-α seems to have no impact on the development of NAFLD in this population. The model incorporating duration, serum transaminase and body mass index presented as a clinical nomogram could well predict the risk of NAFLD in patient with CD.