ABSTRACT
Introduction: Natural history of COVID-19 is yet unknown. A standardized follow-up may allow evaluating different patterns of COVID-19 evolution. AIM: To describe imaging and clinical-functional pulmonary data at 3- (T3) and 12-months (T12) follow-up in COVID19 patients. Method(s): COVID-19 patients discharged from Pisa University Hospital, Italy, from March to September 2020 were evaluated. Expert radiologists qualitatively assessed the evolution of COVID-19 pneumonia CT signs (PS) (baseline acute disease vs. T3) by using an original coding system. A chest CT at T12 was performed only in patients who had persistent PS at T3. Both at T3 and T12, all the patients underwent spirometry, plethysmography, DLCO and pulmonary visit. Result(s): Among 307 discharged patients, 57% and 44.3% were followed up at T3 and T12, respectively, while 12.4% died within T3. Followed patient's characteristics were: 62.9% men;median age 60.3 yrs;11.3% smokers and 30.6% ex-smokers;mean BMI 29.1 kg/mq;43.8% had 1+ comorbidities;median hospitalization 15 days;17.4% stayed 3+ days in ICU. At T3, 52.1% of patients showed resolution of PS, 82.8% had normal spirometry and 76.7% normal DLCO. Among patients with persistent PS at T3 (47.9%), 59.4% showed stability or improvement and 39.1% resolution of PS at T12. 31.6% had persistent PS at T12. An increased proportion of patients with normal lung function was observed at T12, but 5.6% and 20.4% had a restrictive pattern and reduced DLCO, respectively. Conclusion(s): About a third of patients show persistence of PS and about a fifth has DLCO abnormalities at 12- months from the acute COVID-19. Further follow-up is planned for these patients.