Respiratory function and CT abnormalities among survivors of COVID-19 pneumonia: a nationwide follow-up study

Abstract

IntroductionConsidering the pulmonary burden caused by acute COVID-19, questions remain of respiratory consequences after recovery. The aim of the study was to describe respiratory function of COVID-19 pneumonia survivors at mid-term follow-up (median 68 days) and assess whether impairments were predicted by acute illness severity or residual CT abnormalities.MethodsResidents of Iceland that had COVID-19 and oxygen saturation ≤94% from 28 February 2020 to 30 April 2021 were offered a clinical follow-up visit with an interview, a 6 min walk test (6MWT), spirometry with gas exchange measurement and chest CT. The results of these examinations were described, grouped by the level of care during acute illness. The associations of disease severity and CT abnormalities at follow-up with subjective dyspnoea, 6MWT results and lung function test results were estimated with regression analyses.ResultsOf 190 eligible patients, 164 (86%) participated in the study. Of those, 32 had never been admitted to hospital, 103 were admitted to hospital without intensive care and 29 had required intensive care. At a follow-up, need for intensive care during acute illness was associated with shorter walking distance on 6MWT, lower oxygen saturation and lower DLCO. Imaging abnormalities at follow-up were observed for most participants (74%) and the magnitude of these changes was associated with decrements in 6MWT distance, oxygen saturation, forced vital capacity and DLCO.ConclusionsThe findings show that impaired exercise capacity and lung physiology at follow-up were primarily observed for patients with COVID-19 pneumonia that required intensive care treatment and/or had persistent imaging abnormalities.

The Predictive Role of C-Reactive Protein, Leukocyte Cell Count, and Soluble Urokinase Plasminogen Activator Receptor for Pulmonary Sequelae in Hospitalized COVID-19 Survivors: A Prospective Single-Center Cohort Study

“…This results in secondary broproliferation (6, 8) hyaline membrane formation, capillary damage, bleeding, brous proliferation of alveolar septa, and pulmonary consolidation, as documented in previous studies (9). Abnormalities in the respiratory function, computed tomography (CT) (10,11) or magnetic resonance imaging (12) were found among survivors of severe COVID-19 pneumonia months after hospitalization.…”

Residual radiological opacities correlate with disease outcomes in ICU-treated COVID-19

“…Lung volumes and ventilatory performance (reduced inspiratory muscle strength, measured as lower MIP) ( 29 ) were decreased in our entire cohort, and this reduction was more pronounced in the patient group with widespread opacities, indicating a persistent post-COVID-19 effect at 15 months. Previous follow-up studies on COVID-19 have shown differences in lung volumes in ICU patients compared with non-ICU inpatients ( 30 ), suggesting that such differences could be related to disease severity. Of our entire ICU cohort, 80% had reduced lung volumes at 9 months follow-up, in contrast to Orzes et al, who observed that approximately one-third of their patients had abnormal findings at 6 months ( 31 ).…”