Ng JJJ, Loo WM, Siah KTH. Associations between irritable bowel syndrome and non-alcoholic fatty liver disease: A systematic review. World J Hepatol 2023; 15(7): 925-938 [PMID: 37547029 DOI: 10.4254/wjh.v15.i7.925]
Corresponding Author of This Article
Kewin Tien Ho Siah, MD, Division of Gastroenterology and Hepatology, National University Hospital, NUHS Tower Block, Level 10, 1E Kent Ridge Road, Singapore 119228, Singapore. kewin_siah@nuhs.edu.sg
Research Domain of This Article
Gastroenterology & Hepatology
Article-Type of This Article
Systematic Reviews
Open-Access Policy of This Article
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/
World J Hepatol. Jul 27, 2023; 15(7): 925-938 Published online Jul 27, 2023. doi: 10.4254/wjh.v15.i7.925
Associations between irritable bowel syndrome and non-alcoholic fatty liver disease: A systematic review
Jareth Jun Jie Ng, Wai Mun Loo, Kewin Tien Ho Siah
Jareth Jun Jie Ng, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore
Wai Mun Loo, AliveoMedical, Mount Alvernia and Mount Elizabeth Hospitals, Singapore 574623, Singapore
Kewin Tien Ho Siah, Division of Gastroenterology and Hepatology, National University Hospital, Singapore 119228, Singapore
Kewin Tien Ho Siah, Department of Medicine, National University Hospital, Singapore 119228, Singapore
Author contributions: Siah KTH contributed to the design and implementation of the research and supervision; Ng JJJ and Loo WM performed the analysis of the results and writing of the manuscript.
Conflict-of-interest statement: The authors declare that there is no conflict of interest.
PRISMA 2009 Checklist statement: The authors have read the PRISMA 2009 Checklist, and the manuscript was prepared and revised accordingly to the PRISMA 2009 Checklist.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (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: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Kewin Tien Ho Siah, MD, Division of Gastroenterology and Hepatology, National University Hospital, NUHS Tower Block, Level 10, 1E Kent Ridge Road, Singapore 119228, Singapore. kewin_siah@nuhs.edu.sg
Received: March 26, 2023 Peer-review started: March 26, 2023 First decision: May 15, 2023 Revised: June 12, 2023 Accepted: July 3, 2023 Article in press: July 3, 2023 Published online: July 27, 2023
Abstract
BACKGROUND
Irritable bowel syndrome (IBS) is associated with obesity and metabolic syndrome. IBS and non-alcoholic fatty liver disease (NAFLD) are highly prevalent entities worldwide and may share similar mechanisms including gut dysbiosis, impaired intestinal mucosal barrier and immune system activation.
AIM
To systematically review their association according to the Preferred Reporting Items for Systemic Review and Meta-analyses guidelines.
METHODS
PubMed, EMBASE and Cochrane Database of Systematic Reviews were searched for relevant papers. Manual searches were also performed.
RESULTS
Six studies were included. Both IBS and NAFLD subjects had significantly more metabolic risk factors like hypertension, obesity, dyslipidaemia and diabetes. Our review showed that 23.2% to 29.4% of NAFLD patients had IBS. IBS was significantly higher in NAFLD patients compared with patients without NAFLD (23.2% vs 12.5%, P < 0.01). A higher proportion of IBS patients had NAFLD (65.8% to 74.0%). IBS patients were three times more likely to have NAFLD compared with non-IBS patients (P < 0.001). Two studies showed a significant correlation between the severity of IBS and NAFLD. The proportion of NAFLD subjects with IBS increased with NAFLD severity.
CONCLUSION
Further prospective studies are warranted to evaluate the relationship and shared pathways between IBS and NAFLD, potentially leading to the development of future therapeutics.
Core Tip: The relationship between irritable bowel syndrome (IBS) and non-alcoholic fatty liver disease (NAFLD) is increasingly recognised but their shared mechanisms remain poorly elucidated. We evaluate the association between IBS and NAFLD and discuss the risk factors and possible common mechanistic pathways including the brain-gut-liver axis, gut dysbiosis and translocation, altered hypothalamic-pituitary-adrenal axis and sleep quality.
