Extent of pulmonary involvement on admission predicts long-term pulmonary and muscular sequelae of COVID-19: A longitudinal computed tomography study

Abstract

Background

Studies on the association between chest computed tomography (CT) findings of extensive pulmonary involvement and long-term pulmonary and extrapulmonary coronavirus disease 2019 (COVID-19) sequelae are lacking. This study aimed to investigate the relationship between the severity of pneumonia on admission and residual pulmonary and extrapulmonary complications at three months post-hospitalization.

Methods

Using data from the Japan COVID-19 Task Force database, we conducted quantitative analysis of CT scans of 164 patients obtained at admission and three months later. The parameters included pneumonia volume, total lung volume, and area and density of the pectoralis muscle (PM), subcutaneous and epicardial adipose tissue, and vertebral bone density.

Results

Patients with extensive pneumonia on admission had high residual pneumonia volumes, reduced lung volumes, and decreased area and density of PM at three months. No significant differences were observed in the adipose tissue or bone parameters. The severity of pneumonia at admission was independently associated with PM atrophy.

Conclusions

CT-based quantification of pneumonia extent during the acute phase of COVID-19 may be useful in predicting long-term pulmonary sequelae and muscle wasting. This approach may allow the objective evaluation of Long COVID and facilitate the identification of potential therapeutic targets.