Investigation of in Hospital COVID-19 Mortality and One-year Follow-up of Lung Function and Health Status

Background: Globally, thousands of patients suffer from postacute COVID-19 syndrome, a condition that already affects our health system. Although there is a growing literature upon the long-term effects of SARS-CoV-2 infection, there are up to date only a few reports on long-term follow-up of pulmonary function after severe COVID-19. Objective: To investigate risk factors for in-hospital COVID-19 fatalities and to assess the lung function and health status at one year after hospital discharge. Methods: Patients who were admitted to the hospital with confirmed COVID-19 and required supplementary oxygen delivery were included in this observational cohort study. Baseline and demographic data and information about hospital stay were obtained by medical charts. Patients were divided in 3 groups: group 1 (intensive care unit (ICU)-invasive mechanical ventilation (IMV), group 2 (high-flow nasal cannula (HFNC) and/or none-invasive ventilation (NIV) and group 3 (regular oxygen delivery treatment). All patients were required to answer health questionnaires at one year after acute infection, while patients in groups 1 and 2 performed dynamic spirometry. Results: The study population consisted of 130 patients. Forty five (35%) patients died at the hospital. Risk factors for in-hospital mortality were age, hypertension, ischemic heart disease, and renal disease. We did not find any significant difference in health scales between the 3 groups. Mean values of both FEV1% and FVC% in groups 1 and 2 were detected within the lower normal limits with no difference between the two groups. Conclusion: The main result of the study is lung function in the lower limit of normal evaluated at one-year follow-up. There were no significant differences related to initial disease severity in lung function and long-term health status, which suggests that more generous lung function testing even in less severely affected patients, could be indicated.