Longitudinal Assessment of Chest CT Findings and Pulmonary Function in Patients after COVID-19.

Background Information on pulmonary sequelae and pulmonary function at 2 years post recovery from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are lacking. Purpose To longitudinally assess changes in chest CT abnormities and pulmonary function in patients after SARS-CoV-2 infection. Materials and Methods In this prospective study, patients discharged from the hospital after SARS-CoV-2 infection between January 15 and March 10, 2020 were considered for enrollment. Patients without chest CT scans on admission or with complete resolution of lung abnormities on discharge were excluded. Three serial chest CT scans and pulmonary function tests were obtained at 6 months (June 20-August 31, 2020), 12 months (December 20, 2020-February 3, 2021), and 2 years (November 16, 2021-January 10, 2022) after symptom onset. The term interstitial lung abnormalities (ILAs) and two subcategories, fibrotic ILAs and non-fibrotic ILAs, were used to describe the residual CT abnormalities on follow-up CT scans. Differences between groups were compared with χ², Fisher's exact test, or independent-samples t-test. Results Totally, 144 participants (median age, 60 [ranges 27-80] years; 79 men and 65 women) were included. On 2-year follow-up CT scans, 39% (56/144) of the subjects presented with ILAs, including 23% (33/144) wi fibrotic ILAs and 16% (23/144) with non-fibrotic ILAs. The remaining 88 cases (61%) showed complete radiological resolution. Over 2 years, the incidence of ILAs gradually decreased (54%, 42% and 39% at 6 months, 12 months and 2 years, respectively; P = .001). Respiratory symptoms (34% vs 15%, P =.007) and abnormal diffusing capacity of the lung for carbon monoxide (DLco,43% vs 20%, P = .004) more frequently occurred in participants with ILAs than those with complete radiological resolution. Conclusions More than one third of participants had persistent interstitial lung abnormalities at 2 years, which were associated with respiratory symptoms and decreased diffusion pulmonary function. See also the editorial by van Beek in this issue.