Lung and physical function in post COVID-19 and clinical and functional associations: a cross-sectional study in Brazil

OBJECTIVE: The purpose of this study was to assess exercise capacity, lung and physical function in COVID-19 survivors, and the association of lesion-level characteristics assessed by chest computed tomography, probable sarcopenia, and percentage of diffusing capacity of the lung for carbon monoxide with clinical and functional variables. METHODS: This study was conducted in Salvador, Bahia, Brazil. All patients had a laboratory-confirmed SARS-CoV-2 infection. The sociodemographic characteristics, COVID-19 exposure history, pulmonary function, computed tomography, and functionality of the participants between 1 and 3 months of diagnosis of the disease were collected. RESULTS: A total of 135 patients after COVID-19 recovery were included in this study. Probable sarcopenia, reduction in percentage of diffusing capacity of the lung for carbon monoxide, and a lower 6-min walk distance were observed after COVID-19 infection. Computed tomography>50% was associated with a longer length of stay and a lower percentage of diffusing capacity of the lung for carbon monoxide. Probable sarcopenia diagnosis was associated with a worse percentage of the predicted 6-min walk distance in relation to the predicted, absolute 6-min walk distance (m), percentage of diffusing capacity of the lung for carbon monoxide, and percentage of total lung capacity. CONCLUSION: Muscle disability and lung dysfunction are common in COVID-19 survivors. Hospitalization was associated with the worst muscle force and diffusing capacity of the lung for carbon monoxide. Computed tomography characteristics could be a marker of prolonged hospital stay after the acute phase of COVID-19. Additionally, the probable diagnosis of sarcopenia could be a marker of impact on walking distance. These results highlight the need for long-term follow-up of those patients and rehabilitation programs.

Automated summary

The study aimed to evaluate exercise capacity, lung and physical function among COVID-19 survivors, and explore the associations between lesion-level characteristics assessed by chest CT, probable sarcopenia, and percentage of diffusing capacity of the lung for carbon monoxide with clinical and functional variables. After COVID-19 infection, probable sarcopenia, reduced diffusing capacity of the lung for carbon monoxide, and decreased 6-minute walk distance were observed. Chest CT>50% was associated with longer hospital stay and lower diffusing capacity of the lung for carbon monoxide. Probable sarcopenia diagnosis was related to worse predicted 6-minute walk distance, absolute 6-minute walk distance (m), diffusing capacity of the lung for carbon monoxide, and total lung capacity percentage. The findings suggest that COVID-19 survivors commonly experience muscle disability and lung dysfunction, and prolonged hospitalization may lead to worsened muscle force and diffusing capacity of the lung for carbon monoxide. Additionally, the probable diagnosis of sarcopenia may impact walking distance. Long-term follow-up and rehabilitation programs are necessary for these patients.