Visceral fat is associated to the severity of COVID-19

Background: Excess visceral fat (VF) or high body mass index (BMI) is risk factors for severe COVID-19. The receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is expressed at higher levels in the VF than in the subcutaneous fat (SCF) of obese patients. Aim: To show that visceral fat accumulation better predicts severity of COVID-19 outcome compared to either SCF amounts or BMI. Methods: We selected patients with symptomatic COVID-19 and a computed tomography (CT) scan. Severe COVID-19 was defined as requirement for mechanical ventilation or death. Fat depots were quantified on abdominal CF scan slices and the measurements were correlated with the clinical outcomes. ACE 2 mRNA levels were quantified in fat depots of a separate group of non-COVID-19 subjects using RT-qPCR. Results: Among 165 patients with a mean BMI of 26.1 +/- 5A kg/m(2), VF was associated with severe COVID-19 (p = 0.022) and SCF was not (p = 0.640). Subcutaneous fat was not different in patients with mild or severe COVID-19 and the SCF/VI ratio was lower in patients with severe COVID-19 (p = 0.010). The best predictive value for severe COVID-19 was found for a VF area >= 128.5 cm(2) (ROC curve), which was independently associated with COVID-19 severity (p < 0.001). In an exploratory analysis, ACE 2 mRNA positively correlated with BMI in VF but not in SCF of non-COVID-19 patients (r(2) = 027 vs 0.0008). Conclusion: Severe forms of COVID-19 are associated with high visceral adiposity in European adults. On the basis of an exploratory analysis ACE 2 in the visceral fat may be a trigger for the cytokine storm, and this needs to be clarified by future studies. (C) 2020 Elsevier Inc. All rights reserved.

Automated summary

The study found that visceral fat accumulation is associated with severe COVID-19 in European adults, while subcutaneous fat is not. An area of visceral fat greater than or equal to 128.5 cm(2) was identified as the best predictor for severe COVID-19.