Bronchovascular texture pattern on quantitative CT reveals airway and vascular remodeling in post-COVID-19 Lungs

The long-term consequences of COVID-19 remain poorly understood.

To assess CT image-based biomarkers and clinical symptoms in COVID-19 survivors approximately 3-4 years after infection.

Eighty post-COVID-19 participants (81% infected with the pre-Alpha strain) underwent pulmonary function tests (PFTs) and inspiratory/expiratory CT at approximately 5 months (Visit 1, V1) and 3-4 years (Visit 2, V2) after infection. At V2, participants completed the St. George's Respiratory Questionnaire (SGRQ), Leicester Cough Questionnaire (LCQ), Fatigue Severity Scale (FSS), modified Medical Research Council Dyspnea Scale (mMRC), and a study-specific symptom and medical history questionnaire. Seventy-eight healthy individuals served as controls. Image-based biomarkers included airway diameter, airway wall thickness, functional small airway disease percentage (fSAD%), ground-glass opacity percentage (GGO%), and bronchovascular percentage (Bronchovascular%).

Post-COVID-19 participants exhibited normal predicted PFT values, but consistently lower DLCO compared with healthy controls at both visits. At V2, they also reported significantly worse SGRQ scores than the general population, indicating reduced quality of life. Although the elevated fSAD% and GGO% observed at V1 largely resolved by V2, several biomarkers of airway and vascular remodeling persisted, including increased Bronchovascular%, airway narrowing and wall thickening, and a compositional shift from large to small airways and a shift from small to large vessels. Persistent symptoms-such as fatigue, brain fog, cough, and hypertension-were associated with these structural abnormalities.

Airway and vascular structural abnormalities persisted in COVID-19 survivors 3-4 years after infection and were associated with ongoing symptoms and reduced quality of life.