Observational Study
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Oct 7, 2019; 25(37): 5676-5686
Published online Oct 7, 2019. doi: 10.3748/wjg.v25.i37.5676
Nonalcoholic fatty liver disease in patients with inflammatory bowel disease: Beyond the natural history
Salvatore Magrì, Danilo Paduano, Fabio Chicco, Arianna Cingolani, Cristiana Farris, Giovanna Delogu, Francesca Tumbarello, Mariantonia Lai, Alessandro Melis, Laura Casula, Massimo C Fantini, Paolo Usai
Salvatore Magrì, Danilo Paduano, Fabio Chicco, Arianna Cingolani, Cristiana Farris, Giovanna Delogu, Francesca Tumbarello, Mariantonia Lai, Alessandro Melis, Laura Casula, Paolo Usai, Department of Medical Sciences and Public Health, University of Cagliari, Monserrato 09042, Italy
Massimo C Fantini, Department of Systems Medicine, University of Rome "Tor Vergata", Rome 00133, Italy
Author contributions: Magrì S, Chicco F, Paduano D, Farris C, Delogu G, Tumbarello F, Lai MA and Melis A contributed to the patient recruitment and data collection; Magrì S, Lai MA and Melis A contributed to the study design; Magrì S, Chicco F, Cingolani A, Farris C, Delogu G and Tumbarello F contributed to the data analysis and writing up of manuscript; Casula L contributed to the statistical analysis; Fantini MC revised the article critically for important intellectual content; Usai P contributed to the development of study concept and design, and study supervision.
Institutional review board statement: The study was reviewed and approved by the Ethics Board of Cagliari (Prot. PG/2018/23).
Informed consent statement: All study participants, or their legal guardian, provided informed written consent prior to study enrollment.
Conflict-of-interest statement: None declared.
STROBE statement: The authors have read the STROBE Statement—checklist of items, and the manuscript was prepared and revised according to the STROBE Statement-checklist of items.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Salvatore Magrì, MD, Doctor, Occupational Physician, Staff Physician, Physician, Department of Medical Sciences and Public Health, University of Cagliari, Presidio Policlinico of Monserrato, Cagliari, SS 554 km 4,500, Monserrato 09042, Italy. salvo10ms@libero.it
Telephone: +39-340-1417976
Received: June 13, 2019
Peer-review started: June 13, 2019
First decision: July 21, 2019
Revised: July 30, 2019
Accepted: August 19, 2019
Article in press: August 19, 2019
Published online: October 7, 2019
Abstract
BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is a frequently reported condition in patients with inflammatory bowel disease (IBD). Both intestinal inflammation and metabolic factors are believed to contribute to the pathogenesis of IBD-associated NAFLD.

AIM

To evaluate the prevalence of steatosis and liver fibrosis (LF) in a cohort of IBD patients and the identification of metabolic- and IBD-related risk factors for NAFLD and LF.

METHODS

IBD patients were consecutively enrolled from December 2016 to January 2018. Demographic, anthropometric and biochemical data were collected so as eating habits. Abdominal ultrasound and transient elastography were performed to evaluate the presence of NAFLD and LF respectively.

RESULTS

A total of 178 consecutive patients were enrolled and included in the analysis (95 Ulcerative colitis, 83 Crohn’s disease). NAFLD was detected by imaging in 72 (40.4%) patients. Comparison between patients with and without NAFLD showed no significant differences in terms of IBD severity, disease duration, location/extension, use of IBD-related medications (i.e., steroids, anti-TNFs, and immunomodulators) and surgery. NAFLD was significantly associated with the presence of metabolic syndrome [MetS; odds ratio (OR): 4.13, P = 0.001] and obesity defined by body mass index (OR: 9.21, P = 0.0002). IBD patients with NAFLD showed higher caloric intake and lipid consumption than those without NAFLD, regardless disease activity. At the multivariate analysis, male sex, advanced age and high lipid consumption were independent risk factors for the development of NAFLD. An increased liver stiffness was detected in 21 patients (16%) and the presence of MetS was the only relevant factor associated to LF (OR: 3.40, P = 0.01).

CONCLUSION

In this study, we demonstrate that risk factors for NAFLD and LF in the IBD population do not differ from those in the general population.

Keywords: Nonalcoholic fatty liver disease, Liver fibrosis, Inflammatory bowel disease, Risk factors, Dietary habits

Core tip: Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, frequently reported in patients with inflammatory bowel disease (IBD). The underlining causes and predisposing factors to NAFLD among IBD patients remain poorly investigated. We performed an observational study enrolling consecutive IBD patients to evaluate the prevalence of steatosis and liver fibrosis and their association with IBD-related risk factors. Our study confirms the epidemiological burden of NAFLD in IBD and demonstrates the absence of intestinal disease-specific risk factors associated to NAFLD, while confirming as risk factors those already identified in the general population. IBD care should not be limited to intestinal disease but should also include metabolic interventions by promoting healthy lifestyle and a correct dietary regimen in order to reduce the occurrence of chronic liver disease.