Opinion Review
Copyright ©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Feb 14, 2023; 29(6): 908-916
Published online Feb 14, 2023. doi: 10.3748/wjg.v29.i6.908
COVID-19 and liver injury in individuals with obesity
Ioannis G Lempesis, Eleni Karlafti, Petros Papalexis, George Fotakopoulos, Kyriakos Tarantinos, Vasileios Lekakis, Stavros P Papadakos, Evangelos Cholongitas, Vasiliki E Georgakopoulou
Ioannis G Lempesis, Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, B15 2TT, United Kingdom
Ioannis G Lempesis, Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre, Maastricht 616 6200, Netherlands
Eleni Karlafti, Department of Emergency, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki 546 21, Greece
Petros Papalexis, Unit of Endocrinology, First Department of Internal Medicine, Laiko General Hospital, National and Kapodistrian University of Athens, Athens 11527, Greece
Petros Papalexis, Department of Biomedical Sciences, University of West Attica, Athens 12243, Greece
George Fotakopoulos, Department of Neurosurgery, General University Hospital of Larisa, Larisa 41221, Greece
Kyriakos Tarantinos, First Pulmonology Department, Sismanogleio Hospital, Athens 15126, Greece
Vasileios Lekakis, Stavros P Papadakos, Department of Gastroenterology, Laiko General Hospital, National and Kapodistrian University of Athens, Athens 11527, Greece
Evangelos Cholongitas, First Department of Internal Medicine, Laiko General Hospital, Medical School, National and Kapodistrian University of Athens, Athens 11527, Greece
Vasiliki E Georgakopoulou, Department of Infectious Diseases-COVID-19 Unit, Laiko General Hospital, Athens 11527, Greece
Author contributions: Karlafti E and Tarantinos K designed the research; Fotakopoulos G, Papalexis P, Lekakis V and Papadakos SP performed the research; Lempesis IG wrote the article; Cholongitas E and Georgakopoulou VE revised the article.
Conflict-of-interest statement: The authors report having no relevant conflicts of interest for this article.
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: Vasiliki E Georgakopoulou, Doctor, MSc, Academic Research, Doctor, Department of Infectious Diseases-COVID-19 Unit, Laiko General Hospital, 17 Agiou Thoma Street, Athens 11527, Greece. vaso_georgakopoulou@hotmail.com
Received: September 12, 2022
Peer-review started: September 12, 2022
First decision: December 12, 2022
Revised: December 18, 2022
Accepted: January 9, 2023
Article in press: January 9, 2023
Published online: February 14, 2023
Abstract

Coronavirus disease 2019 is an infectious disease caused by the severe acute respiratory syndrome coronavirus 2 that manifests as a variety of clinical manifestations, including liver damage commonly detected by a hepatocellular pattern from liver function tests. Liver injury is associated with a worse prognosis overall. Conditions associated with the severity of the disease include obesity and cardiometabolic comorbidities, which are also associated with nonalcoholic fatty liver disease (NAFLD). The presence of NAFLD, similarly to obesity, is associated with an unfavourable impact on the coronavirus disease 2019 outcome. Individuals with these conditions could present with liver damage and elevated liver function tests due to direct viral cytotoxicity, systemic inflammation, ischemic or hypoxic liver damage or drug side effects. However, liver damage in the setting of NAFLD could also be attributed to a pre-existing chronic low-grade inflammation associated with surplus and dysfunctional adipose tissue in these individuals. Here we investigate the hypothesis that a pre-existing inflammatory status is exacerbated after severe acute respiratory syndrome coronavirus 2 infection, which embodies a second hit to the underestimated liver damage.

Keywords: COVID-19, SARS-CoV-2, Non-alcoholic fatty liver disease, Obesity, Inflammation, Liver, Adipose tissue

Core Tip: The severe acute respiratory syndrome coronavirus 2 that causes coronavirus disease 2019 has a variety of clinical manifestations, including liver damage. Obesity and other dysmetabolic diseases linked to nonalcoholic fatty liver disease are a few of the factors that contribute to the severity of the illness. Due to direct viral cytotoxicity, people with these illnesses may have liver damage and increased liver function tests. However, liver injury might also be related to pre-existing inflammation and the detrimental effects of excessive and dysfunctional adipose tissue in these people.