In a latest study published online within the American Thoracic Society’s American Journal of Respiratory and Critical Care Medicine, researchers sought to find out the share of COVID-19 patients discharged from the hospital who had a style of fibrotic lung damage, generally known as interstitial lung disease, that requires ongoing follow-up care. These patients had various degrees of COVID-19 severity at hospital admission.

In “Residual Lung Abnormalities Following COVID-19 Hospitalization: Interim Evaluation of the UKILD Long-COVID Study,” the authors examined evidence of abnormal lung patterns on follow-up CT scans from COVID-19 patients discharged from the hospital-;patterns which might be suggestive of interstitial lung disease. The characteristics of the 209 study participants who had CT scans were applied to a wider post-hospitalization cohort of just about 3,500 people with out a CT to stratify risk of residual lung abnormalities.

“Interstitial lung disease” refers to a broad group of diseases which can be characterised by lung scarring, including idiopathic lung fibrosis. This scarring makes it difficult to breathe and get oxygen into the bloodstream. Lung damage from this group of diseases could also be irreversible and worsen over time.

We estimated that as much as 11 percent of hospitalized COVID patients had fibrotic patterning after recovery from the acute illness. Whilst many individuals experience prolonged breathlessness, the main implication of those findings is that a considerable number of individuals discharged from a COVID hospitalization may have fibrotic abnormalities of their lungs. These results should help concentrate efforts to closely follow at-risk patients. This follow-up should include repeat radiological imaging and lung function testing.”

Iain Stewart, PhD, corresponding writer, advanced research fellow (Rayne Foundation), Margaret Turner Warwick Centre for Fibrosing Lung Disease, National Heart and Lung Institute, Imperial College London

He added, “For some people these fibrotic patterns could also be stable or resolve, while for others they might result in long run lung fibrosis progression, worse quality of life and decreased life expectancy. Earlier detection of progression is crucial to improving outcomes.”

The UK Interstitial Lung Disease (UKILD) study was performed in cooperation with the PHOSP (post hospitalization)-COVID study, which consists of researchers and clinicians from across the UK, to have a look at how different patients who were hospitalized with COVID-19 subsequently recovered. The UKILD COVID study excluded patients in PHOSP-COVID who had interstitial lung disease prior to COVID-related hospital admission.

Interim study participants were discharged from the hospital by the top of March 2021, while interim data were collected until October 2021, restricting the evaluation to 240 days after discharge. The researchers identified patients with thoracic CTs from the PHOSP-COVID database. The first final result they sought to find out was the prevalence of residual lung abnormalities in people discharged from a COVID-19 hospitalization. Analyses were performed to find out participants’ risk aspects of residual lung abnormalities in those that didn’t receive a CT scan. These risks were used to estimate prevalence in the general population hospitalized by the top of March 2021.

In keeping with the authors, “The UKILD Post-COVID interim evaluation of residual lung abnormalities in patients hospitalized for COVID-19 offers the most important assessment of prevalence in hospitalized individuals to this point, and is consistent with findings from plenty of smaller studies that reveal persistent radiological patterns and impaired gas transfer through the prolonged follow up of patients with COVID-19. On the time of this interim evaluation it isn’t possible to find out whether the observed residual lung abnormalities represent early interstitial lung disease with potential for progression, or whether or not they reflect pneumonitis that could be stable or resolve over time.”

“The subsequent phase of the study is a primary evaluation, which can be performed at 12 months. At the moment, we will even use linked electronic health records of hospital admissions and mortality data to support our analyses. We expect to have the ultimate leads to early 2023.”

Source:

American Thoracic Society

Journal reference:

Stewart, I., et al. (2022) Residual Lung Abnormalities Following COVID-19 Hospitalization: Interim Evaluation of the UKILD Long-COVID Study. American Journal of Respiratory and Critical Care Medicine. doi.org/10.1164/rccm.202203-0564OC .