Chest CT Lung Abnormalities 1 Year after COVID-19: A Systematic Review and Meta-Analysis
Marialuisa Bocchino, Gaetano Rea, Ludovica Capitelli, Roberta Lieto, Dario Bruzzese
Abstract
Background Radiologic lung sequelae may explain the persistence of respiratory symptoms in post–coronavirus disease (post–COVID-19) condition (long COVID). Purpose To perform a systematic review and meta-analysis of the prevalence and type of COVID-19 residual lung abnormalities at 1-year chest CT. Materials and Methods A literature search of PubMed, Web of Science, Embase, and Medline databases was performed for articles published from January 2020 to January 2023. Full-text reports of CT lung sequelae in adults (≥18 years) with confirmed COVID-19 at 1-year follow-up were included. The prevalence of any residual lung abnormality and type (fibrotic or not) was analyzed according to the Fleischner Society glossary. The meta-analysis included studies with chest CT data assessable in no less than 80% of individuals. A random-effects model was used to estimate pooled prevalence. Multiple subgroup (country, journal category, methodologic quality, study setting, outcomes) and metaregression analyses were performed to identify potential sources of heterogeneity. The I2 statistics estimated low (25%), moderate (26%–50%), and high (>50%) heterogeneity, and 95% prediction intervals (PIs) were computed to describe the expected estimates range. Results Of 22 709 records, 21 studies were reviewed (20 prospective, nine from China, and seven in radiology journals). The meta-analysis included 14 studies with chest CT data in 1854 of 2043 individuals (1109 male, 934 female). Estimates of lung sequelae were highly heterogeneous (range, 7.1%–96.7%), with a pooled frequency of 43.5% (I2 = 94%; 95% PI: 5.9, 90.4). This also applied to single nonfibrotic changes, including ground-glass opacity, consolidations, nodules or masses, parenchymal bands, and reticulations. The prevalence range of fibrotic traction bronchiectasis or bronchiolectasis was 1.6%–25.7% (I2 = 93%; 95% PI: 0.0, 98.6); honeycombing was unremarkable (range, 0%–1.1%; I2 = 58%; 95% PI: 0, 60). Lung sequelae were unrelated to any characteristics of interest. Conclusion The prevalence of COVID-19 lung sequelae at 1-year chest CT is highly heterogeneous among studies. Heterogeneity determinants remain unknown, suggesting caution in data interpretation with no convincing evidence. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Parraga and Svenningsen in this issue.