Insights into Long COVID: Unraveling Risk Factors, Clinical Features, Radiological Findings, Functional Sequelae and Correlations: A Retrospective Cohort Study.

Background: The long-term symptomatology of COVID-19 has yet to be comprehensively described. The aim of the study was to describe persistent COVID-19 symptoms in a cohort of hospitalized and home-isolated patients.

Methods: A retrospective cohort study was conducted on long COVID patients. Long COVID symptoms were identified, and patients were divided into hospitalized (in-patients) and home-isolated (out-patients), as well as according to the number of symptoms. Patients were examined by a multidisciplinary medical team. Blood tests, high resolution chest computed tomography (CT), and physical and infectious examinations were performed. Finally, in-patients were evaluated at 2 time-points: on hospital admission (T0) and 3 months after discharge (Tpost).

Results: There were 364 COVID-19 patients enrolled; 82% of patients reported one or more symptoms. The most reported symptom was fatigue. Chest CT showed alteration in 76% of patients, and pulmonary function alterations were observed in 44.7% of patients. A higher risk of presenting at least one symptom was seen in patients treated with corticosteroid, and a higher risk of presenting chest CT residual lesion was observed in hospitalized patients and in patients that received hydroxychloroquine treatment. Moreover, a higher risk of altered pulmonary function was observed in older patients.

Conclusion: Long-term sequelae are present in a remarkable number of long COVID patients and pose a new challenge to the health care system to identify long-lasting effects and improve patients' well-being. Multidisciplinary teams are crucial to develop preventive measures, and clinical management strategies.