At 3-4 years post-COVID-19, participants exhibited persistent airway-vascular remodeling on quantitative CT, including elevated Bronchovascular% and vessel size shifts, despite normalized spirometry.
Cohort (n=158)
Quantitative CT and computational modeling reveal persistent airway and vascular remodeling 3-4 years after COVID-19 infection, despite normal spirometry, which correlates with ongoing symptoms.
Abstract Rationale Long-term cardiopulmonary consequences of post-acute sequelae of SARS-CoV-2 infection (PASC, “Long COVID”) remain poorly characterized beyond two years, particularly using quantitative CT (qCT) and computational fluid and particle dynamics (CFPD) metrics. Methods We prospectively studied 80 adults with prior COVID-19 (81% infected pre-Alpha; unvaccinated at infection) who completed inspiratory and expiratory chest CT and spirometry at approximately 5 months (Visit-1, V1) and again at 3-4 years (Visit-2, V2). Seventy-eight healthy adults served as controls. At V2, post-COVID-19 participants completed the St. George’s Respiratory Questionnaire (SGRQ), Leicester Cough Questionnaire (LCQ), Fatigue Severity Scale (FSS), and modified MRC Dyspnea Scale (mMRC). Quantitative CT (qCT) metrics included airway diameter and wall thickness, functional small-airway disease percentage (fSAD%), ground-glass opacity percentage (GGO%), and an adaptive multiple-feature method (AMFM)-based “Bronchovascular%,” quantifying bronchovascular texture. A whole-lung CFPD model was applied to assess airway resistance. Statistical analyses included ANOVA with Tukey post hoc tests, Mann-Whitney U tests, Spearman correlations, and logistic regression. Results Group-average spirometry values were within normal limits at V1 and V2 and did not differ from controls. Questionnaires at V2 (SGRQ, LCQ, and mMRC) indicated that participants remained symptomatic after 3-4 years. From V1 to V2, fSAD% and GGO% decreased, suggesting resolution of small-airway dysfunction and parenchymal opacities. In contrast, structural remodeling persisted: (1) Bronchovascular% remained elevated at V2 compared with controls. (2) Airway metrics showed smaller normalized hydraulic diameters and thicker walls than controls at both time points, and although airway resistance decreased from V1 to V2, it remained higher than in healthy controls. (3) Vessel metrics demonstrated a redistribution toward larger vessels with a loss of small-vessel volume, which correlated with dyspnea, fatigue, chest pain, and cardiovascular comorbidities. Conclusion In post-COVID-19 subjects followed for 3-4 years after recovery, spirometry normalized, but qCT metrics revealed persistent airway-vascular remodeling, characterized by elevated Bronchovascular% and complementary airway and vessel size shifts. These structural changes were associated with worse symptoms and reduced quality of life. AMFM-based Bronchovascular% may serve as a candidate imaging biomarker for long-term PASC burden. Funding Sources NIH Grant R01-HL168116, P30 ES005605, and ED P116S21000 This abstract is funded by: National Institutes of Health: Department of Education
Zhang et al. (Fri,) conducted a cohort in Post-acute sequelae of SARS-CoV-2 infection (PASC) (n=158). Prior COVID-19 infection vs. Healthy adults was evaluated on Quantitative CT metrics, computational fluid and particle dynamics, and symptom questionnaires. At 3-4 years post-COVID-19, participants exhibited persistent airway-vascular remodeling on quantitative CT, including elevated Bronchovascular% and vessel size shifts, despite normalized spirometry.