Long-Term Post COVID-19 Respiratory Sequelae Study Reveals Evolving of Pulmonary Lesions Up to Two Years after Hospitalization

Background: COVID-19 lung sequelae can impact the course of patient lives. We investigate the evolution of pulmonary abnormalities in post-COVID-19 patients two years after hospitalization.Methods: A prospective cohort of COVID-19 patients admitted to the Hospital das Clínicas da Faculdade de Medicina da USP in Brazil, between March and August of 2020, were followed-up 6-12 months after hospitalization. A subset of patients with pulmonary involvement and chest computed tomography (CT) scans were eligible to participate in this second follow-up (18-24 months). Dyspnea scale (mMRC), pulse oximetry, blood tests, CT scans and pulmonary function tests were performed. Statistical models were used to evaluate predictors of fibrotic-like lung lesions.Findings: From 348 patients eligible, 237 participated in this follow-up. 139 presented ground-glass opacities and reticulations, and 80 presented fibrotic-like lesions (traction bronchiectasis and architectural distortion). CT revealed that 2·1% of patients improved compared to the 6-12-month assessment, but 25% presented worsening of lung abnormalities, with increased architectural distortion (p=0·002), traction bronchiectasis (p=0·003), mosaic attenuation (p<0·001) and bronchial wall thickening (p<0·001). Patients presented a persistent functional impairment with demonstrated restrictive pattern and reduced diffusion capacity. Length of ICU care, invasive mechanical ventilation, age, tracheostomy, use of vasoactive drug, and patient’s sex were consistent predictors for marking development of late fibrotic-like lung lesions.Interpretation: This study demonstrated that pos-COVID-19 lung sequelae can progress, suggesting airways involvement and formation of new fibrotic-like lesions, mainly in patients who were under ICU care.Funding: São Paulo Research Foundation (22/01769-5) and the Instituto Todos pela Saúde (C1721).Declaration of Interest: We declare no competing interests.Ethical Approval: The study was approved by the Research Ethics Committee of our institution (No. 31942020.0.000.0068). The informed consent was signed by all patients.