As of February 10, 2020, 544 patients admitted to Zhongnan Hospital and Xishui hospital and107 patients discharged. Basic characteristics of the 107 patients (95 from Zhongnan and 12 from Xi-Shui) are shown in Table 1. There were 88 survivors and 19 non-survivors. Median age was 51 years (IQR, 36-65; range, 19-92 years), 57 (53.3%) were male. Median times from first symptoms to hospital admission, dyspnea, and ARDS were 7 days (IQR, 3.5-9), 5.5 days (IQR, 2-9.3), and 7.5 days (IQR, 4.3-11), respectively. Median length of hospital stay was 11 days (IQR, 7-15). In this cohort of 107 patients, hypertension (26 [24.3%]), cardiovascular disease (13 [12.1%]) and diabetes (11 [10.3%]) were the most common coexisting conditions. The most common symptoms at onset of illness were fever (104 [97.2%]), dry cough (67 [62.6%]), fatigue (69 [64.5%]), dyspnea (35 [32.7%]), anorexia (33[30.8%]) and myalgia (33[30.8%]). Less common symptoms were sore throat, headache, dizziness, abdominal pain, diarrhea, nausea, and vomiting. At hospital admission median respiratory rate was 20/minute [IQR, 19-21] and mean arterial pressure was 89 mmHg [IQR, 83-98].
In comparison to the 88 hospital survivors, the 19 non-survivors were significantly older (median age, 73 years [IQR, 64-81] vs 44.5 years [IQR, 35-58.8]; p < .001) and were predominantly male (16 [84.2%] vs 41 [46.6%]; p=.003). Non-survivors were more likely to have underlying comorbidities, including hypertension (10 [52.6%] vs 16 [18.2%]; P=.001) and other cardiovascular disease (7 [36.8%] vs 6 [6.8%]; P=.002). Compared with the survivors, non-survivors were more likely to report dyspnea (15[78.9%] vs 20 [22.7%]; P < .001) and diarrhea (4[21.1%] vs 3[3.4%]; P=.018) at presentation. At hospital admission respiratory rate was higher in survivors than in non-survivors (22 [IQR 20-24] vs 20 [19-21]; p=.003). Similarly, mean arterial pressure was higher in non-survivors than in survivors (95mmHg [IQR 89-101] vs 88mmHg [83-96]; P=.019).
Laboratory values and radiographic findings
Laboratory values and radiographic findings at hospital admission are shown in Table 2. Lymphopenia (0.9×10⁹/L [0.7-1.2]) and prolonged prothrombin time (12.8[11.9-13.5]) at admission were prominent features. 90 (84.1%) patients showed multi-lobar involvement on initial radiographs. 105 (98.1%) patients showed bilateral involvement on chest CT scan during hospitalization. Compared with survivors, on admission non-survivors had higher neutrophil counts (5.4×10⁹/L[3.2-8.5] vs 2.8×10⁹/L [2-3.9], P＜0.001, lower platelet count (122×10⁹/L [83-178] vs 178 [139-207], P=0.006) and higher D-dimer level (439 mg/L [202-1991] vs 191mg/L [108-327], P=0.003). Admission values of blood urea, creatinine, highly sensitive troponin I, serum creatine kinase, creatine kinase-MB, lactate dehydrogenase, alanine aminotransferase, aspartate aminotransferase were also significantly higher in the non-survivors.
Clinical Profile and Laboratory Findings in COVID-19 Patients
Temporal clinical profiles in 107 patients with COVID-19 are shown in Figure 2. Trends of temperature and onset of positive nucleic acid amplification test (NAAT) were consistent. Fever typically lasts for about 10 days. Most patients (about 75%) demonstrated positive NAAT results (measured every 2-3 days) within 9 days after symptoms onset. The median time from illness onset to first positive result of NAAT was 7 days (3.0-10.0) and the duration of active viral shedding was 13 days (IQR, 10-22.3) in survivors. In the majority of cases development of ARDS and need for endotracheal intubation occurred within 9 days after symptoms onset.
Dynamic body temperature and laboratory findings in 107 COVID-19 patients are shown in supplementary Figure 1. During the first week after symptoms onset, fever was prominent and more severe in the non-survivors. Body temperature gradually normalized in the second week. In general, white blood cell counts and neutrophils counts were in normal range during week 1, with leukocytosis and neutrophilia as later findings. Lymphopenia was common throughout the disease’s course and the lymphocytes count dropped more in non-survivors. Platelets counts decreased slightly in the first week, then rose back to normal range rapidly in survivors, but remained low in non-survivors. Mild prolongation of prothrombin time (PT) during the illness course was observed, with no difference between survivors and non-survivors. D-dimer level was Elevated in the non-survivors during the late stage of illness. In the early stage of the illness, higher levels of creatine kinase, creatine kinase-MB, lactate dehydrogenase, alanine aminotransferase and aspartate aminotransferase were observed in the non-survivors than those in the survivors. In non-survivors, blood urea and creatinine levels progressively increased until death.
Complications, treatments and outcome
Common complications included ARDS (28[26.2%]), shock (22 [20.6%]), AKI (14[13.1%]) and acute cardiac injury (12[11.2%]) (Table 3). Non-survivors were more likely to have one of these complications than survivors. Secondary infection included 1 case of bacteremia caused by Staphylococcus caprae and 4 cases of bacteria pneumonia caused by Acinetobacter baumannii. Co-infection with virus included 1 patient tested positive for influenza A, two for influenza B, three for respiratory syncytial virus, three for parainfluenza and 3 for adenovirus. Almost all patients received antiviral therapy (105 [98.1%]). Among of them, 95(88.8%) patients received oseltamivir and 33 (30.8%) patients received arbidol. Glucocorticoids were administered in 62 [57.9%] patients. Oxygen therapy was applied in (80 [74.8%] patients. In total, 20 patients required invasive mechanical ventilation. On day 1 of invasive mechanical ventilation, the median PaO2/FiO2 ratio was 103 (IQR 58-172) and the median APACHE II score was 25 (IQR 17-32). Three patients received extracorporeal membrane oxygenation (ECMO) therapy, Two of them survived and were discharged at day 26 and day 32, and one died due to sudden cardiac arrest after connection to the ECMO circuit. The causes of death included refractory ARDS (15 [78.9%]), septic shock (1 [5.3%]), sudden cardiac arrest (1 [5.3%]), hemorrhagic shock (1 [5.3%]) and acute myocardial infarction (1 [5.3%]).
Risk factors associated with death for COVID-19
On univariate analysis, risk factors associated with death at hospital admission were older age, male gender, hypertension, diabetes, cardiovascular disease, raised white blood cell counts, elevated level of neutrophil counts, thrombocytopenia, creatine kinase-MB, lactate dehydrogenase, alanine aminotransferase, aspartate aminotransferase and creatinine (Table 4). On multivariable analysis, older age and male gender remained significant independent risk factors for death (Table 5).