Visceral Adiposity and High Intramuscular Fat Deposition Independently Predict Critical Illness in Patients with SARS-CoV-2

Abstract

Objective: This study aimed to assess the association between adipose tissue distribution and severity of clinical course in patients with severe acute respiratory syndrome coronavirus 2.

Methods: For this retrospective study, 143 hospitalized patients with confirmed coronavirus disease 2019 (COVID-19) who underwent an unenhanced abdominal computed tomography (CT) scan between January 1, 2020, and March 30, 2020, were included. Univariate and multivariate logistic regression analyses were performed to identify the risk factors associated with the severity of COVID-19 infection.

Results: There were 45 patients who were identified as critically ill. High visceral to subcutaneous adipose tissue area ratio (called visceral adiposity) (odds ratio: 2.47; 95% CI: 1.05-5.98, P = 0.040) and low mean attenuation of skeletal muscle (called high intramuscular fat [IMF] deposition) (odds ratio: 11.90; 95% CI: 4.50-36.14; P < 0.001) were independent risk factors for critical illness. Furthermore, visceral adiposity or high IMF deposition increased the risk of mechanical ventilation (P = 0.013, P < 0.001, respectively). High IMF deposition increased the risk of death (P = 0.012).

Conclusions: COVID-19 patients with visceral adiposity or high IMF deposition have higher risk for critical illness. Therefore, patients with abdominal obesity should be monitored more carefully when hospitalized.

Figure 1

Flowchart for inclusion and exclusion criteria of our cohort.

Figure 2

Cross‐sectional computed tomography (CT) images of the third lumbar vertebra used to quantify adipose tissue distribution variables. (A) Subcutaneous adipose tissue (SAT) area is between the yellow and red lines, and skeletal muscle area is between the red and green lines. (B) Visceral adipose tissue (VAT) area is inside the green lines, excluding"/> non‐VAT fat within abdominal organs. VSR, VAT to SAT ratio.

Figure 3

Cumulative rates of mechanical ventilation and mortality were calculated using Kaplan‐Meier methods, and differences between curves were evaluated using the log‐rank test. (A) Time‐dependent risk of mechanical ventilation from the time of onset between patients with or without visceral adiposity. (B) Time‐dependent risk of mechanical ventilation between patients with or without high intramuscular fat (IMF) deposition. (C) Time‐dependent risk of death from the time of onset between patients with or without visceral adiposity. (D) Time‐dependent risk of death between patients with or without high IMF deposition. (Two of the enrolled individuals were excluded from analysis because record of time of onset was unavailable.)