Abstract
BACKGROUND: We aimed to describe respiratory sequelae up to 4 years after discharge in COVID-19 patients with severe pneumonia having required non-invasive respiratory support therapies. METHODS: This study was conducted between March 2020 and June 2020 at University Hospital Doctor Josep Trueta (Girona, Spain). We assessed the patient's dyspnoea and performed, pulmonary function tests, a high-resolution CT (HRCT), a 6-minute walking test, a blood test, and the Saint George's respiratory questionnaire 3 months after discharge. At the 6-month, 1-year, and 4-year follow-up, we repeated all tests except for pulmonary function, 6-min walking test, and HRCT, which were only performed if abnormal findings had been previously detected. RESULTS: 94 patients were enrolled 3 months after discharge; 73% were male, the median age was 62.9 years, and most were non-smokers (58%). 56 patients (59.6%) completed the 4-year follow-up. When comparing data 3 months and 4 years after discharge, the percentage of patients presenting dyspnoea ≥ 2 decreased (19.5% vs. 7.9%), the quality-of-life total score improved (22.8% vs. 18.1%), diffusing capacity for carbon monoxide improved (75.9% vs. 81.4%), the 6-min walking test distance was enhanced (368.0 m vs. 436.6 m), ground glass opacities findings waned (56.6% vs. 0.8%), and traction bronchiectasis increased (2.7% vs. 9.2%). Age was the only parameter that exhibited significant differences between patients with and without pulmonary fibrotic-like changes. CONCLUSION: Most patients, 4 years after discharge, improved their pulmonary function, exercise capacity, clinical condition, and quality of life. Although pulmonary fibrotic-like changes were observed during the follow-ups, its disparity with clinical-functional improvement pointed to non-progressive and non-clinically relevant lung scars.