Post-COVID-19 chest imaging evaluation: which patients should be prioritized for follow-up pulmonary assessment?

Objectives: The current study evaluated the long-term lung abnormalities based on initial and follow-up chest computed tomography (CT) images of COVID-19 patients and investigates the possible factors associated with them. Methods: One hundred and twenty-four hospitalized COVID-19 patients who received a follow-up chest CT scan in three hospitals in Tehran between February 20, 2021 and September, 2021, were included. Based on the presence of persistent lesions in the follow-up images, patients were divided into residual and nonresidual groups, and logistic regression analysis was performed to investigate the association between different disease characteristics and long-term lung abnormalities. Results: The most frequent abnormality in the initial imaging was ground-glass opacities which was observed in 95.3% of patients, and residual lesions were observed in 39.8% of patients at the follow-up date. Patients in the residual group were generally older, more frequently suffered from hypertension and dyspnea, and had lower oxygen saturation and lymphocyte count, and lymphopenia was more prevalent among them. Moreover, patients in the residual group had higher initial lung involvement score, and the presence of lymphadenopathy and consolidation was more frequent among them. After adjustment for age, gender, and intervals between the two imagings, logistic regression results showed that hospitalization period, dyspnea, decreased oxygen saturation, decreased lymphocyte count, lymphopenia, consolidation, lymphadenopathy, and high initial lung involvement were strongly associated with the presence of long-term abnormalities. Conclusion: The current study revealed multiple discrepancies between residual and nonresidual groups, which can be used to better identify the patients at risk of long-term COVID-19 lung complications.