Non-alcoholic fatty liver is associated with increased risk of irritable bowel syndrome: a prospective cohort study

Shanshan Wu; Changzheng Yuan; Zhirong Yang; Si Liu; Qian Zhang; Shutian Zhang; Shengtao Zhu

doi:10.1186/s12916-022-02460-8

Non-alcoholic fatty liver is associated with increased risk of irritable bowel syndrome: a prospective cohort study

BMC Med. 2022 Aug 22;20(1):262. doi: 10.1186/s12916-022-02460-8.

Authors

Shanshan Wu¹, Changzheng Yuan^{2

3}, Zhirong Yang^{4

5}, Si Liu¹, Qian Zhang¹, Shutian Zhang¹, Shengtao Zhu⁶

Affiliations

¹ Department of Gastroenterology, National Clinical Research Center for Digestive Disease, Beijing Digestive Disease Center, Beijing Key Laboratory for Precancerous Lesion of Digestive Disease, Beijing Friendship Hospital, Capital Medical University, Beijing, 100050, China.
² School of Public Health, Zhejiang University School of Medicine, Hangzhou, Zhejiang, 310058, China.
³ Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, 02115, USA.
⁴ Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China.
⁵ Primary Care Unit, Department of Public Health and Primary Care, School of Clinical Medicine, University of Cambridge, Cambridge, CB18RN, UK.
⁶ Department of Gastroenterology, National Clinical Research Center for Digestive Disease, Beijing Digestive Disease Center, Beijing Key Laboratory for Precancerous Lesion of Digestive Disease, Beijing Friendship Hospital, Capital Medical University, Beijing, 100050, China. zhushengtao@ccmu.edu.cn.

Abstract

Background: The relationship between non-alcoholic fatty liver degree as well as non-alcoholic fatty liver disease (NAFLD) and irritable bowel syndrome (IBS) remains poorly understood. We aimed to investigate the prospective association of non-alcoholic fatty liver degree as well as NAFLD with incident IBS in a large-scale population-based cohort.

Methods: Participants free of IBS, coeliac disease, inflammatory bowel disease, alcoholic liver disease, and any cancer at baseline from the UK Biobank were included. Non-alcoholic fatty liver degree was measured by a well-validated fatty liver index (FLI), with FLI ≥ 60 as an indicator of NAFLD. Primary outcome was incident IBS. Cox proportional hazard model was used to investigate the associated risk of incident IBS.

Results: Among 396,838 participants (mean FLI was 48.29 ± 30.07), 153,203(38.6%) were with NAFLD diagnosis at baseline. During a median of 12.4-year follow-up, 7129 cases of incident IBS were identified. Compared with non-NAFLD, NAFLD patients showed a 13% higher risk of developing IBS (HR = 1.13, 95%CI: 1.05-1.17) after multivariable adjustment. Compared with the lowest, the highest FLI quartile was associated with a significantly increased risk of IBS (HR_{Q4 VS Q1} = 1.21, 1.13-1.30, P_trend < 0.001). Specifically, the positive association between non-alcoholic fatty liver degree and IBS was also observed by per SD change of FLI (adjusted HR = 1.08, 1.05-1.10). Further sensitivity analysis and subgroup analysis indicated similar results, with the positive association particularly observed in females, but not in males.

Conclusions: High degree of non-alcoholic fatty liver as well as non-alcoholic fatty liver disease is associated with increased risk of incident IBS. Further studies are warranted to confirm the findings and elucidate the underlying biological mechanisms.

Keywords: Cohort study; Irritable bowel syndrome; Non-alcoholic fatty liver disease.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Cohort Studies
Female
Humans
Irritable Bowel Syndrome* / complications
Irritable Bowel Syndrome* / epidemiology
Male
Non-alcoholic Fatty Liver Disease* / complications
Non-alcoholic Fatty Liver Disease* / diagnosis
Non-alcoholic Fatty Liver Disease* / epidemiology
Prospective Studies
Risk Factors

Abstract

Publication types

MeSH terms

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