CT Lung Abnormalities after COVID-19 at 3 Months and 1 Year after Hospital Discharge.

Background Data on the long-term pulmonary sequelae in COVID-19 are lacking. Purpose To assess symptoms and functional impairment and residual pulmonary abnormalities on serial chest CT in COVID-19 survivors discharged from hospital at up to 1-year follow-up. Materials and Methods Adult patients with COVID-19 discharged between March 2020 and June 2020 were prospectively evaluated at 3 months and 1 year, through systematic assessment of symptoms, functional impairments, and thoracic CT as part of the PHENOTYPE study, an observational cohort study in COVID-19 survivors. Lung function testing was limited to participants with CT abnormalities and/or persistent breathlessness. All statistical analyses were performed using Graphpad PRISM Version 9.0 (86) for Mac, GraphPad Software, (www.graphpad.com); Bonferroni corrected p values are stated. Results Eighty participants (mean age, 59 ±13 years; 53 men) were assessed. Persistent breathlessness 37 (46%) and cough 17 (21%) were reported at outpatient review (median 97 days [IQR 86-121]). CT scans in 73 participants post-discharge (median 105 days [IQR 95-141]) revealed persistent abnormalities in 41/73 participants (56%), with ground-glass opacification (35/73 [48%]) and bands (27/73 [37%]) predominating. Unequivocal signs indicative of established fibrosis (i.e. volume loss +/- traction bronchiectasis) were present in 9/73 (12%) participants. Higher admission serum C-reactive protein (mg/L), fibrinogen (g/dl), urea (mmol/L) and creatinine (micromol/L), longer hospital stay (days), older age (years) and requirement for invasive ventilation were associated with CT abnormalities at 3-month follow-up. 32/41 (78%) of participants with abnormal 3-month follow-up CT underwent repeat imaging at a median of 364 (360-366) days, with 26/32 (81%) showing further radiological improvement (median 18% [IQR 10-40%]). Conclusion CT abnormalities were common at 3 months after COVID-19 but with signs of fibrosis in a minority. More severe acute disease was linked with CT abnormalities at 3 months. However, radiologic improvement was seen in the majority at 1-year follow-up. ClinicalTrials.gov Identifier: NCT04459351.