TABLE 1a

Baseline characteristics of the study population

Non-Severe disease No mechanical ventilationSevere disease Mechanical Ventilation necessaryp-Value
n=92n=51 (55.4%)n=41 (44.6%)
Age, mean±sd60.2±15.857.9±18.163.1±12.70.258
Male, n (%)71 (77.3%)36 (70.6%)34 (82.9%)0.22
Continuous oxygen insufflation, n (%)61 (66.3%)21 (41.2%)41 (100%)<0.001
Admission to ICU, n (%)47 (51.1%)9 (17.6%)41 (100%)<0.001
Days of mechanical ventilation±sdn.a.22.6±14.1n.a.
Days of hospitalisation±sd18.5±13.413.1±7.825.3±15.6<0.001
Use of ECMO, n (%)5 (5.4%)n.a.5 (12.2%)n.a.
Days of ECMO usen.a.13.6±3.8n.a.
ECMO mortality, n (%)n.a.3 (60%)n.a.
Discharge, n (%)66 (72.5%)45 (88.2%)21 (47.2%)<0.001
Fatal, n (%)7 (7.6%)0 (0.0%)7 (17.9%)0.003
Presence of COVID-19 typical radiological changes, n (%)85 (92.4%)44 (86.3%)41 (100%)0.013
Initial viral load in nose swabs (copies·mL−1sd12.8×106±41.1×10612.6×106±43.1×10613.0×106±39.9×1060.127
Initial viral load in endotracheal aspirate (copies·mL−1sdn.a.67.2×106±273×106n.a.
Duration of viral shedding in days (with twice confirmed negativity)±sd18.7±12.013.9±9.5 (n=16)25.8±11.8 (n=18)0.025
Persistent viral shedding (≥17 days), n (%)44 (47.8%)14 (27.5%)30 (73.2%)<0.001
Time to first testing in days±sd7.4±4.76.5±4.08.4±5.30.12
Comorbidities n (%)
 Arterial hypertension48 (52.2%)24 (47.1%)24 (58.5%)0.30
 Diabetes mellitus Type 218 (19.6%)8 (15.7%)10 (24.4%)0.43
 Coronary artery disease15 (16.3%)9 (17.6%)6 (14.6%)0.78
 COPD11 (12.0%)4 (7.8%)7 (17.1%)0.21
 Immunosuppression22 (23.9%)13 (25.5%)9 (22.0%)0.81
Charlson comorbidity index±sd2.5±1.82.5±1.92.6±1.70.62

Data are mean (sd) or n (%). p values were calculated by Mann-Whitney U test or χ² test, as appropriate. Severe disease was defined by the need of mechanical ventilation. COVID-19 typical changes included either ground glass opacities or diffuse bilateral infiltrates. Duration of nasopharyngeal viral shedding was defined by the time between symptom begin and last positivity for viral shedding in standardized nose swabs or endotracheal aspirates.