Retrospective Study
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Apr 21, 2020; 26(15): 1792-1804
Published online Apr 21, 2020. doi: 10.3748/wjg.v26.i15.1792
Prevalence, clinical characteristics, risk factors, and indicators for lean Chinese adults with nonalcoholic fatty liver disease
Jing Zeng, Rui-Xu Yang, Chao Sun, Qin Pan, Rui-Nan Zhang, Guang-Yu Chen, Ying Hu, Jian-Gao Fan
Jing Zeng, Rui-Xu Yang, Chao Sun, Qin Pan, Rui-Nan Zhang, Ying Hu, Department of Gastroenterology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200092, China
Guang-Yu Chen, Clinical Epidemiology Research Center, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200092, China
Jian-Gao Fan, Department of Gastroenterology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Children’s Digestion and Nutrition, Shanghai 200092, China
Author contributions: Zeng J and Yang RX contributed equally to this work; Zeng J, Yang RX, and Zhang RN carried out the experiments; Zeng J, Yang RX, Sun C, Pan Q, and Chen GY contributed to acquisition, analysis, or interpretation of the data; Zeng J and Yang RX wrote the paper; Hu Y and Fan JG made critical revision of the manuscript for important intellectual content.
Supported by National Key R&D Program of China, No. 2017YFC0908900; National Natural Science Foundation of China, No. 81873565 and No. 81900507; Hospital Funded Clinical Research, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, No. 17CSK04 and No. 15LC06.
Institutional review board statement: The study was reviewed and approved by the ethics committees of all hospitals involved. All procedures were performed in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1975, as revised in 2008.
Informed consent statement: Informed consent was obtained from all individual participants included in the study.
Conflict-of-interest statement: The authors declare that they have no conflict of interest.
Data sharing statement: No additional data are available.
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: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Jian-Gao Fan, MD, PhD, Professor, Department of Gastroenterology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Children’s Digestion and Nutrition, No. 1665, Kongjiang Road, Yangpu District, Shanghai 200092, China. fanjiangao@xinhuamed.com.cn
Received: December 25, 2019
Peer-review started: December 25, 2019
First decision: January 19, 2020
Revised: March 19, 2020
Accepted: March 27, 2020
Article in press: March 27, 2020
Published online: April 21, 2020
Processing time: 118 Days and 1.8 Hours
ARTICLE HIGHLIGHTS
Research background

Nonalcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases in the world. Considerable attention has been paid to be the prevalence of and risk factors for NAFLD in obese subjects. However, the percentage of non-obese or lean NAFLD patients are increasing and these patients may have a worse outcome compared to their obese counterpart.

Research motivation

As the non-obese or lean individuals may not visit clinics for NAFLD diagnosis or ignore the diagnosis of NAFLD, it might lead to more problems than obese individuals. So, it is critically important to find the precise characteristics of these populations, especially the lean subgroup, which can help clinicians provide appropriate advice and treatment to these populations.

Research objectives

In this study, we aimed to investigate the prevalence, clinical characteristics, and risk factors for NAFLD in lean individuals, and finally identify the possible indicators in screening for NAFLD in these populations.

Research methods

The participant characteristics and anthropometric indices, including height, weight, and waist circumference (WC), were obtained. Their fatty liver index (FLI), abdominal ultrasonography results, and controlled attenuation parameter were all assessed. In another small group consisting of biopsy-proven NAFLD subjects and healthy controls, genotyping for single-nucleotide polymorphisms associated with NAFLD was performed.

Research results

Among lean participants with a normal WC, the percent of the people who fulfilled the diagnostic criteria for NAFLD was 17.5%. The significant associated factors with the presence of NAFLD in these participants included waist-height-ratio, hemoglobin, platelets, and triglycerides. The appropriate cut-off value of the FLI score in screening for NAFLD in the lean subjects with normal WC was lower than the value we often used.

Research conclusions

The results from this study suggest that NAFLD is not uncommon in Chinese lean adults even with a normal WC. A lean subject with high waist-height ratio, hemoglobin, platelet count, or hypertriglyceridemia may be the best to be referred for an abdominal ultrasound examination. A lower cutoff value of the FLI has been obtained for lean Chinese with a normal WC.

Research perspectives

This study clearly highlights the need for paying more attention to the diagnosis of NAFLD by abdominal ultrasound even in lean subjects. The cut-off values of non-invasive diagnostic methods for NAFLD may vary based on different populations. In future, application of precise anthropometric strategies and identification of the relationships between other risk factors and the development and progression of NAFLD in this population would be required.