# Assessment of the Abnormalities in Chest Computed Tomography and Pulmonary Function Test in Convalescents Six Months After COVID-19

## TL;DR

This study found that most chest CT abnormalities in people who recovered from COVID-19 six months ago have resolved, with lung function tests showing no significant differences compared to the general population.

## Contribution

The study provides evidence that post-COVID-19 pulmonary abnormalities largely resolve over time and suggests prioritizing pulmonary function tests over CT scans in follow-up care.

## Key findings

- Most chest CT abnormalities in post-COVID-19 patients six months after infection were clinically insignificant.
- Pulmonary function tests showed no significant differences between post-COVID-19 patients and a general population cohort.
- Abnormalities on CT scans did not vary significantly based on disease severity or SARS-CoV-2 variant.

## Abstract

Background: Despite the multiple waves of the COVID-19 pandemic, follow-up strategies for recovered patients remain inconclusive. This study aimed to evaluate chest computed tomography (CT) and pulmonary function test (PFT) abnormalities in convalescents six months after COVID-19 and to compare these findings with those from a representative population cohort. The goal was to support more individualized pulmonary management of post-COVID-19 sequelae. Methods: This study population consisted of 2 groups: I—232 post-COVID-19 patients and II—543 patients from a population cohort. Chest CT was performed during the acute phase of COVID-19 and six months after. The PFTs were conducted six months after COVID-19. Results: There were no significant differences in FEV1, FVC, TLC, and DLCO in the two study groups. A singular GGO in 24 patients (20%), a crazy paving pattern in 1 patient (0.8%), thickening of interlobular septa in 4 patients (3.5%), consolidations in 4 patients (3.5%), traction bronchiectasis in 6 patients (5%), fibrosis in 6 patients (5%), and singular nodular densities in 68 patients (58%) were observed in chest CT 6 months after COVID-19. Most radiological abnormalities were clinically insignificant and did not require further diagnostic evaluation. No significant differences in chest CT and PFT six months after infection were observed between patients differing in the severity of inflammation during the acute disease or SARS-CoV-2 variant. Conclusions: The majority of chest CT abnormalities resolved within six months of recovery, regardless of SARS-CoV-2 variant or initial disease severity. Pulmonary function tests should be prioritized in post-COVID-19 follow-up, as PFT results in convalescents were comparable to those observed in the general population.