Respiratory and functional outcomes among severe COVID-19 infection survivors: a prospective observational study

Patients who have severe to critical COVID-19 infection may experience persistent or new symptoms after discharge. Our objective is to determine the first-year post-discharge respiratory and functional outcomes in patients who survived COVID-19 infection. In this prospective and observational study, we recruited Malaysians above 18 years old who survived severe or critical COVID-19 and followed them up for 1 year. Patients completed the post-COVID-19 Functional Status (PCFS) scale, performed the 6-minute walk test, and a standard spirometry. In the final analysis, 94 patients were included. Median age was 57 years (24,86); 55 (57.3%) were men, and 20 (20.8%) required invasive ventilation. Overall, 45 (46.9%) had underlying hypertension, 33 (34.4%) had diabetes mellitus, 43 (44.8%) had hospital-acquired infection, 19 (19.8%) had raised liver enzymes, and 17 (17.7%) suffered pulmonary embolism. From discharge to 1 year following discharge, the percentage of patients with dyspnea reduced from 51.4% to 25.0%, while patients with cough reduced from 16.2% to none, and fatigue from 20.0% to 12.5%. The percentage of patients with PCFS of 0 increased from 48.0 to 62.5%, while no more patients reported PCFS scales of 3 or 4 after 24 weeks. The median 6-minute walk distance within 1 to 8 weeks was 375.0 m (108.0, 540.0). This increased to 500.0 m (330.0, 680.0) at 41 to 48 weeks. Throughout the follow-up, the percentage of patients with normal spirometry findings increased from none at 1 to 8 weeks to 43.8% at 41 to 48 weeks. In conclusion, patients gradually regained their functional status. Follow-up for patients with persistent symptoms and abnormal spirometry is necessary to determine their long-term outcome.