Retrospective Study
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Surg. Jun 27, 2020; 12(6): 269-276
Published online Jun 27, 2020. doi: 10.4240/wjgs.v12.i6.269
Role of micronutrients in staging of nonalcoholic fatty liver disease: A retrospective cross-sectional study
Franciele Sabadin Bertol, Bruna Araujo, Brunno Brochado Jorge, Natalino Rinaldi, Luiz Alberto De Carli, Cristiane Valle Tovo
Franciele Sabadin Bertol, Bruna Araujo, Brunno Brochado Jorge, Natalino Rinaldi, Luiz Alberto De Carli, Cristiane Valle Tovo, Graduate Program of Medicine, Hepatology, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, RS 90430080, Brazil
Author contributions: Tovo CV conceptualized the manuscript; Bertol FS, Araujo B and Jorge BB collected the data; Bertol FS and Tovo CV wrote the manuscript; All authors helped to perform the research, performed the final review with significant contributions, and approved the final version of the manuscript.
Institutional review board statement: This study agrees with resolution 466 of 2012, which governs the conduct of human subjects research, and was approved by the Research Ethics Committee of the institution concerned (opinion number 982.654).
Informed consent statement: Patients were not required to give informed consent to the study because the analysis used anonymous clinical data that were obtained after each patient agreed to treatment.
Conflict-of-interest statement: The authors declare no conflicts of interest.
Data sharing statement: No additional data are available. Data used and/or analyzed during this study are available upon request to the author.
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: Cristiane Valle Tovo, MD, PhD, Adjunct Professor, Graduate Program of Medicine, Hepatology, Universidade Federal de Ciências da Saúde de Porto Alegre, Rua Sarmento Leite 245, Porto Alegre, RS 90430080, Brazil. cristianev@ufcspa.edu.br
Received: December 15, 2019
Peer-review started: December 15, 2019
First decision: April 2, 2020
Revised: April 10, 2020
Accepted: May 5, 2020
Article in press: May 5, 2020
Published online: June 27, 2020
Abstract
BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) presents high incidence throughout the world and has been progressively increasing in prevalence. This disease has a heterogeneous natural history, including simple steatosis, nonalcoholic steatohepatitis (NASH), and cirrhosis. The factors that determine its evolution to more severe forms of the disease are still poorly understood, and micronutrients with antioxidant potential may be involved in the pathophysiology of the disease.

AIM

To evaluate the relationship between serum levels of micronutrients and the severity of NAFLD.

METHODS

A retrospective, observational and cross-sectional study was conducted. This study included all patients undergoing bariatric surgery who experienced liver biopsy during the procedure, and had serum levels of micronutrients (vitamin D, vitamin B12, zinc, iron, and magnesium), which was assessed in a preoperative evaluation conducted at a reference center in southern Brazil.

RESULTS

A total of 614 patients were analyzed, of which 93% had steatosis, 70.7% had NASH, and 49.3% had some degree of fibrosis. Serum levels of vitamin D were negatively correlated with the severity of steatosis and NASH, and serum levels of vitamin B12 were positively correlated with the severity of steatosis and fibrosis. The other micronutrients showed no association with NAFLD staging.

CONCLUSION

Serum levels of vitamin D are inversely related to the severity of steatosis and NASH, and serum levels of vitamin B12 are higher in more advanced stages of simple steatosis and liver fibrosis. Serum levels of zinc, iron, and magnesium were not associated with NAFLD severity.

Keywords: Nonalcoholic fatty liver disease, Nonalcoholic steatohepatitis, Liver cirrhosis, Micronutrients, Vitamin D, Vitamin B12, Zinc, Iron, Magnesium

Core tip: Nonalcoholic fatty liver disease presents with a high incidence throughout the world, and micronutrients may be involved in the pathophysiology of the disease. This study evaluated the relationship between serum levels of micronutrients and the severity of nonalcoholic fatty liver disease. Six hundred and fourteen patients undergoing bariatric surgery that had serum levels of micronutrients (vitamin D, vitamin B12, zinc, iron, and magnesium) as assessed in a preoperative period were included. Vitamin D levels were negatively correlated with the severity of steatosis and nonalcoholic steatohepatitis, and vitamin B12 levels were positively correlated with the severity of steatosis and fibrosis. In conclusion, vitamin D and vitamin B12 are related to the severity of steatosis, nonalcoholic steatohepatitis, and liver fibrosis.