A prospective cohort study for characterization and predictive factors of long-term POST-COVID interstitial changes

Chronic interstitial lung changes are potential long-term sequelae of severe COVID-19. This study aims to evaluate the prevalence and type of interstitial changes over time and identify serum biomarkers associated with persistent lung abnormalities. Prospective, multicenter, observational cohort study of patients with severe COVID-19 pneumonia between March 2020 and June 2021. Clinical evaluation, pulmonary function tests (PFTs), and chest high-resolution computed tomography (HRCT) were performed at baseline and up to 24 months. Serum biomarkers were assessed at baseline and at 12 months. Of the 290 patients enrolled, 247 completed the follow-up. Mild dyspnea (mMRC1) was the most common residual symptom. PFTs showed significant improvement: mean FVC increased from 88.8% to 99.5%, and DLCO from 71.6% to 82%. Among patients with baseline DLCO < 80% (n = 67), only 38.8% achieved normalization. Radiological improvement was observed in all patients, though 32% of the 118 patients assessed at 24 months still had residual changes, primarily mild reticulation, ground glass opacities, and lower lobes traction bronchiectasis. Pulmonary functional improvement correlated with radiological resolution, especially during the first year. Elevated baseline levels of MMP-7 and KL6 were associated with persistent interstitial abnormalities at 12 months. Severe COVID-19 survivors exhibit progressive functional and radiological improvement, particularly within the first year. However, a subset of patients shows long-term interstitial changes. Elevated MMP-7 and KL-6 levels may help identify individuals at higher risk for persistent interstitial changes.

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Publication Details

Journal
Respiratory Research
Published
2026-04-22
DOI
https://doi.org/10.1186/s12931-026-03678-3
Primary Topic
Long-Term Effects of COVID-19
Type
article
Field-Weighted Citation Impact
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article

A prospective cohort study for characterization and predictive factors of long-term POST-COVID interstitial changes

R Planas, P Luburich, Eva Balcells, Guadalupe Bermudo et al.
Respiratory Research
Long-Term Effects of COVID-19
article

A prospective cohort study for characterization and predictive factors of long-term POST-COVID interstitial changes

R Planas, P Luburich, Eva Balcells, Guadalupe Bermudo, F. Climent, Ana Montes‐Worboys, L Pijuan, R. Llatjós, S. Barril, J. Bordas-Martinez, Diana Badenes‐Bonet, V Vicens-Zygmunt, S. Bolívar, C. Valenzuela, M. Molina-Molina, Belen del Rio, M. Gasa, Karina Portillo, Paloma Millán-Billi, Guillermo Suárez-Cuartín, Jessica González, Joan Sabater‐Riera, A Lagarda, S. Santos, XL. Perez-Fernandez, A. Robles-Perez, M. Hernandez-Argudo, S. López-Monzoni, A. Moreno, M. Fuentes, Y. Gutierrez, H. Jofre-Grimaldo, J. Peñafiel, MP. Fuset, R. Menendez
article en

Abstract

Chronic interstitial lung changes are potential long-term sequelae of severe COVID-19. This study aims to evaluate the prevalence and type of interstitial changes over time and identify serum biomarkers associated with persistent lung abnormalities. Prospective, multicenter, observational cohort study of patients with severe COVID-19 pneumonia between March 2020 and June 2021. Clinical evaluation, pulmonary function tests (PFTs), and chest high-resolution computed tomography (HRCT) were performed at baseline and up to 24 months. Serum biomarkers were assessed at baseline and at 12 months. Of the 290 patients enrolled, 247 completed the follow-up. Mild dyspnea (mMRC1) was the most common residual symptom. PFTs showed significant improvement: mean FVC increased from 88.8% to 99.5%, and DLCO from 71.6% to 82%. Among patients with baseline DLCO < 80% (n = 67), only 38.8% achieved normalization. Radiological improvement was observed in all patients, though 32% of the 118 patients assessed at 24 months still had residual changes, primarily mild reticulation, ground glass opacities, and lower lobes traction bronchiectasis. Pulmonary functional improvement correlated with radiological resolution, especially during the first year. Elevated baseline levels of MMP-7 and KL6 were associated with persistent interstitial abnormalities at 12 months. Severe COVID-19 survivors exhibit progressive functional and radiological improvement, particularly within the first year. However, a subset of patients shows long-term interstitial changes. Elevated MMP-7 and KL-6 levels may help identify individuals at higher risk for persistent interstitial changes.

Respiratory Research
Universitat Pompeu Fabra (ES), Bellvitge University Hospital (ES), Hospital Universitari Arnau de Vilanova (ES), Institut d'Investigació Biomédica de Bellvitge (ES), Hospital General de Granollers (ES), Centre for Biomedical Network Research on Rare Diseases (ES), Hospital Arnau de Vilanova (ES), Leitat Technological Center (ES), Hospital de Sabadell (ES), Hospital Universitario de La Princesa (ES), Hospital Del Mar (ES), Hospital de Mataró (ES), Hospital Universitari Germans Trias i Pujol (ES), Medical Research Network (US)
Instituto de Salud Carlos III
Good health and well-being
Openalex Percentile: Top 7%
Long-Term Effects of COVID-19
DOIOpen Access PDFOpenAlex
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