Long-term lung abnormalities common 1 year after COVID-19 pneumonia

Long-term CT abnormalities were common up to 1 year after COVID-19 pneumonia in a study published in Radiology.

Researchers performed a secondary analysis of CovILD, a prospective, multicenter, observational cohort study, conducted from April to August 2020. The study evaluated pulmonary abnormalities on chest CT at 2, 3 and 6 months and 1 year after COVID-19 symptoms in 142 adults who had mild to severe COVID-19. Researchers graded pulmonary CT findings for each lung lobe and assessed associations between demographic and clinical factors with CT abnormalities at 1 year. The study was conducted in Austria.

“Tyrol in Austria was one of the first epidemic areas due to winter tourism, so we were confronted with high patient numbers early on, which is why we quickly assembled a study cohort in close collaboration with our colleagues in pulmonology,” Christoph Schwabl, MD, from the department of radiology at the Medical University of Innsbruck in Austria, told Healio.

Overall, 91 participants from the CovILD study (mean age, 59 years; 38% women) had 1-year follow-up CT data and were included in the secondary analysis.

“More than half of the hospitalized participants still have permanent lung changes 1 year after COVID-19,” Schwabl told Healio.

Among the 54% of participants with CT abnormalities 1 year later, 34% had subtle subpleural reticulation, ground-glass opacities or both and 20% had extensive ground-glass opacities, reticulations, bronchial dilation and/or microcystic changes in the lung.

Age older than 60 years (OR = 5.8; 95% CI, 1.7-24; P = .009), critical COVID-19 severity (OR = 29; 95% CI, 4.8-280; P < .001) and male gender (OR = 8.9; 95% CI, 2.6-36; P < .001) were associated with persistent CT abnormalities at 1 year in this population.

On subsequent follow-up CTs, researchers observed a reduction in CT severity score (P < .001). During the study period, 49% of participants had complete CT abnormality resolution and 63% of participants with abnormalities did not show further improvement after another 6 months.

“Now, in further studies, we need to clarify whether these changes that we found in our study regress over time, remain stable or, in the worst case, become progressive and develop toward pulmonary fibrosis,” Schwabl said.

For more information:

Christoph Schwabl, MD, can be reached at christoph.schwabl@i-med.ac.at.