Pulmonary long-term consequences of COVID-19 infections after hospital discharge

Abstract

Objectives COVID-19 survivors are reporting residual abnormalities after discharge from the hospital. Limited information is available about this stage of recovery or the lingering effects of the virus on pulmonary function and inflammation. The aim of this study was to describe lung function and to identify biomarkers in serum and induced sputum samples from patients recovering from COVID-19 hospitalisation. Methods Patients admitted to Spanish hospitals with laboratory-confirmed COVID-19 infection by a real-time PCR (RT-PCR) assay for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were recruited for this study. Each hospital screened their lists of discharged patients at least 45 days after symptom onset. SARS-CoV-2-infected patients were divided into mild/moderate and severe disease groups according to the severity of their symptoms during hospitalisation. Patients’ epidemiological and medical histories, comorbidities, chronic treatments, and laboratory parameters were evaluated. Pulmonary function tests, the standardised 6-minute walk test (6 MWT) and chest computed tomography (CT) were also performed. The levels of proteases, their inhibitors, and shed receptors were measured in serum and induced sputum samples. Results A total of 100 patients with respiratory function tests were included in this study. The median number of days after the onset of symptoms was 104 (IQR 89.25, 126.75). COVID-19 was severe in 47% (47/100) of patients. CT was normal in 48% (48/100) of patients. Lung function was normal (FEV1 ≥80%, FVC ≥80%, FEV1/FVC ≥0.7, and diffusing capacity for carbon monoxide [DLCO] ≥80%) in 92% (92/100), 94% (94/100), 100% (100/100) and 48% (48/100) of patients, respectively. Multivariate analysis showed that a DLCO <80% (OR 5.92; 95%CI 2.28-15.37; p <0.0001) and a lower serum LDH level (OR 0.98; 95%CI 0.97-0.99) were associated with the severe disease group of SARS-CoV-2 during hospital stay. Conclusions A diffusion deficit (DLCO <80%) was still present after hospital discharge and was associated with the most severe SARS-CoV-2 cases.

Abnormal pulmonary function and imaging studies in critical COVID-19 survivors at 100 days after the onset of symptoms

“…In the present study, 94% of the patients had CT abnormalities at approximately 100 days after symptom onset. This percentage is higher than previous COVID-19 reports because we exclusively examined critical cases ( 21 ) ( 22 ). In one study in which patients requiring invasive mechanical ventilation were excluded, follow-up CT assessments were performed for 100 patients recovering from COVID-19 hospitalization, and the authors found that 52% of the patients had abnormal CT findings at approximately 100 days after the onset of symptoms ( 21 ).…”

“…This percentage is higher than previous COVID-19 reports because we exclusively examined critical cases ( 21 ) ( 22 ). In one study in which patients requiring invasive mechanical ventilation were excluded, follow-up CT assessments were performed for 100 patients recovering from COVID-19 hospitalization, and the authors found that 52% of the patients had abnormal CT findings at approximately 100 days after the onset of symptoms ( 21 ). In another study, 90-day follow-up CT scans were performed for 52 patients recovering from COVID-19 (11 of the patients were in the ICU), and the authors found CT abnormalities in 58% of the patients ( 22 ).…”

1-year outcomes in hospital survivors with COVID-19: a longitudinal cohort study

“…As of early August, 2021, more than 200 million COVID-19 cases have been confirmed globally, and more than 4•3 million people have died following SARS-CoV-2 infection. 1 The sequelae after recovery from acute COVID-19 have been widely reported [2][3][4][5][6][7][8][9][10][11][12] and have become an increasing concern. In our previous cohort study with a median follow-up time of 6 months after symptom onset, approximately three-quarters of COVID-19 survivors discharged from hospital still had persisting symptoms, and patients who were critically ill during hospital stay had higher risk of lung diffusion impairment and radiographic abnormality than did those who had lower disease severity.…”

Characterising long term Covid-19: a living systematic review

“…Twenty-two studies included people requiring ICU admission during the acute phase. [25,27–29,31,32,34–49]…”

“…The longest follow-up period in any study was a mean of 221.7 (SD: 10.9) days post-onset. Only 56% (22/39) of studies specified Covid-19 severity [25,27–29,31,32,34–49], 31% (12/39) treatment received during the acute phase [30,34,35,39,40,44,47,50–54], and 62% (24/39) described ventilation support requirements. [30–36,39,40,42–45,47,48,50,51,54–60] Pre-existing comorbidities were reported in the majority of studies (85%, 33/39), with hypertension and diabetes most commonly documented.…”