COVID-19 and liver injury in individuals with obesity

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

Figure 1

Potential mediators of liver damage associated to coronavirus disease 2019, fatty liver, and obesity. ACE2: Angiotensin converting enzyme 2; SARS-CoV-2: Severe acute respiratory syndrome coronavirus 2. Parts of the figure were drawn by using pictures from Servier Medical Art (smart.servier.com).