Epidemiological, demographic and baseline Characteristics
In our cohort the first patient was identified on 26 January. The process of enrollment was shown in Fig. 1. By 15 March 2020, 122 admitted hospitalized patients were diagnosed with COVID-19, among which 62 (50.82%) cases were allocated to severe group. From the beginning to the end, the number of severe cases accounted for a large proportion (Supplement 1).
As seen in Table 1, the median age was 64.0 years (IQR 57.0–71.0). Most of them were male (55.74%). The majority of patients denied the history of smoke. The kind and extent of clinical symptoms varied from person to person, while fever (83.61%) was the most common symptoms at the outset of illness. The respiratory rate of severe cases was significantly higher than non-severe ones (P < 0.0001) (Table 1). Comorbidities were universally existed in patients with COVID-19. In detail, 67.21% patients affected with COVID-19 suffered from comorbidity-54 patients had hypertension, 29 patients had diabetes, 19 patients had coronary heart disease, 8 had cerebrovascular disease and 7 patients had chronic obstruction pulmonary disease. In addition, the incidence of other underlying diseases was less than 5%, such as liver disease (3.28%), malignancy (1.64%) and kidney disease (1.64%). The proportion of patients with comorbidity was higher in severe group although there was no statistically significant difference. The comparison of demographic and baseline characteristics between survival and non-survival inpatients were also shown in Table 1. Single-factor analysis suggested that several factors were related to severity of disease while they were not associated with death among severe inpatients, which concluded BMI and respiratory rate. Surprisingly, the most common symptom།fever was found to be concerned with death(P = 0.027).
Table 1
Demographics and baseline characteristics of patients with Coronavirus Disease 2019
Characteristic
|
All patients (N = 122)
|
|
Severe patients(N = 62)
|
|
|
|
|
Non-severe
(N = 60)
|
Severe
(N = 62)
|
P value#
|
Survive
(N = 44)
|
Death
(N = 18)
|
P value*
|
Age, median (IQR), yr
|
64 (57–71)
|
64.5 (58-70.5)
|
63.5(56–72)
|
0.9320
|
63.5(55–71)
|
63.5(57–73)
|
0.7147
|
Sex, no.(%)
|
|
|
|
|
|
|
|
Female
|
54 (44.26)
|
28 (46.67)
|
26 (41.94)
|
0.5990
|
21(47.73)
|
5(27.78)
|
0.1480
|
Male
|
68 (55.74)
|
32 (53.33)
|
36 (58.06)
|
|
23(52.27)
|
13(72.22)
|
|
Smoking history, no./total No.(%)
|
|
|
|
|
|
|
|
Never smoked
|
80 (65.57)
|
41 (68.33)
|
39 (62.90)
|
0.0860
|
30(68.18)
|
9(50.00)
|
0.3930
|
Current smoker
|
31 (25.41)
|
11 (18.33)
|
20 (32.26)
|
|
12(27.27)
|
8(44.44)
|
|
Ever smoker
|
11 (9.02)
|
8 (13.33)
|
3 (4.84)
|
|
2(4.55)
|
1(5.56)
|
|
BMI, median (IQR)
|
23.77(22.22–25.71)
|
24.27(22.76–25.88)
|
23.11(21.22–25.39)
|
0.0094
|
23.08(21.50-24.59)
|
23.14(20.80-27.14)
|
0.2614
|
Comorbidity (Yes/No)
|
82(67.21)
|
39(65.00)
|
43(69.35)
|
0.6080
|
30(68.18)
|
13(72.22)
|
0.7540
|
Comorbidity (Number)
|
|
|
|
|
|
|
|
=0
|
40(32.79)
|
21(35.00)
|
19(30.65)
|
0.8180
|
14(31.8)
|
5(27.78)
|
0.7010
|
=1
|
48(39.34)
|
22(36.67)
|
26(41.94)
|
|
17(38.64)
|
9(50.00)
|
|
≥ 2
|
34(27.87)
|
17(28.33)
|
17(27.42)
|
|
13(29.55)
|
4(22.22)
|
|
Comorbidity No. (%)
|
|
|
|
|
|
|
|
Hypertension
|
54 (44.26)
|
28 (46.67)
|
26 (41.94)
|
0.5990
|
20(45.55)
|
6(33.33)
|
0.3800
|
Diabetes mellitus
|
29 (23.77)
|
12 (20.00)
|
17 (27.42)
|
0.3360
|
10(22.73)
|
7(38.89)
|
0.1950
|
COPD
|
7 (5.74)
|
3 (5)
|
4 (6.45)
|
0.7300
|
4(9.09)
|
0(0)
|
0.1860
|
Coronary heart disease
|
19 (15.57)
|
10 (16.67)
|
9 (14.52)
|
0.7430
|
7(15.91)
|
2(11.111)
|
0.6260
|
Cerebrovascular disease
|
8 (6.56)
|
4 (6.67)
|
4 (6.45)
|
0.9620
|
3(6.82)
|
1(5.56)
|
0.8540
|
Malignancy
|
2 (1.64)
|
0 (0)
|
2 (3.23)
|
0.1610
|
1(2.27)
|
1(5.56)
|
0.5070
|
Chronic liver disease
|
4 (3.28)
|
2 (3.33)
|
2 (3.23)
|
0.9730
|
1(2.27)
|
1(5.56)
|
0.5070
|
Chronic kidney disease
|
2 (1.64)
|
1 (1.67)
|
1 (1.61)
|
0.9810
|
1(2.27)
|
0(0)
|
0.5190
|
Fever
|
102 (83.61)
|
50 (83.33)
|
52 (83.87)
|
0.9360
|
34(77.27)
|
18(100)
|
0.0270
|
Respiratory rate, median (IQR)
|
22 (20–26)
|
20 (20–22)
|
26 (22–30)
|
0.0000
|
26(22.5–30)
|
27(22–30)
|
0.8936
|
Onset of symptom to hospital admission, median (IQR), d
|
10 (7–14)
|
10 (7–15)
|
9.5(7–12)
|
0.1517
|
10(7-12.5)
|
9(7–12)
|
0.3839
|
#P values indicate differences between Non-severe and Severe patients. |
*P values indicate differences between survival and dead patients. |
P < 0.05 was considered statistically significant. |
Laboratory findings and radiological characteristics
The laboratory findings and radiological characteristics were collected on admission and summarized in Table 2. In the severe group, leukocyte counts significantly increased compared with non-severe group(P = 0.0053). The cell counts of neutrophil(P = 0.0002) and lymphocyte(P < 0.0001) were further analyzed. It was shown that both of them were elevated in severe group. However, the difference of lymphocyte count between survival and dead group was not significant. Then there was a significant difference between the two groups regarding coagulation function index such as D-dimer, fibrinogen and prothrombin time.
Table 2
Laboratory findings and radiological characteristics of patients infected with Coronavirus Disease 2019 on admission to hospital
|
Normal Range
|
All patients (N = 122)
|
|
Severe Patients (N = 62)
|
|
|
|
Non-severe (N = 60)
|
Severe (N = 62)
|
P value#
|
Survive
(N = 44)
|
Death
(N = 18)
|
P value*
|
White blood cell count, ×109/L
|
3.50–9.50
|
5.15 (4.10–7.90)
|
5.80 (4.15–5.55)
|
6.20 (4.10-9.00)
|
0.0053
|
5.45(3.95–7.75)
|
8.95(6-11.5)
|
0.0015
|
Neutrophil count, ×109/L
|
1.80–6.30
|
3.55 (2.59–6.67)
|
3.14 (2.37–3.86)
|
4.57 (3.10–7.57)
|
0.0002
|
3.86(2.94–6.69)
|
7.70(4.35–9.89)
|
0.0011
|
Lymphocyte count, ×109/L
|
1.10–3.20
|
0.89 (0.65–1.20)
|
1.09 (0.83–1.48)
|
0.78 (0.51–0.97)
|
0.0000
|
0.75(0.52–0.95)
|
0.81(0.35–0.97)
|
0.3495
|
Median Hemoglobin, g/L
|
115–150
|
124 (112–133)
|
124 (113–130)
|
124 (109–136)
|
0.7492
|
124(110–134)
|
130(109–145)
|
0.8004
|
D-dimer, mg/L
|
0-0.50
|
1.17 (0.49–4.10)
|
0.64 (0.39–2.65)
|
1.70 (0.74–5.29)
|
0.0027
|
1.12(0.5–4.8)
|
2.53(2.10-5.00)
|
0.8699
|
Fibrinogen, g/L
|
2.0–4.0
|
4.46 (3.60–5.14)
|
4.10 (3.20–4.78)
|
4.86 (3.90–5.31)
|
0.0187
|
4.84(3.72–5.29)
|
4.94(4.06–5.31)
|
0.4493
|
Prothrombin time, s
|
10.00–13.00
|
11.80(11.20-12.45)
|
11.50 (11.10–12.10)
|
12.00 (11.10-12.75)
|
0.0354
|
11.95(11.5–12.6)
|
12.3(11.2–13.4)
|
0.6934
|
Alanine aminotransferase, U/L
|
7–40
|
32 (19.5–50)
|
32 (19.5–53.5)
|
32.5 (19.5–46.5)
|
0.9482
|
30(19–48)
|
34(20–38)
|
0.7540
|
Aspartate aminotransferase, U/L
|
0–45.00
|
31.50 (23.00–49.00)
|
28.00 (22.00–38.00)
|
36.50 (25.00–58.00)
|
0.0018
|
24.00(35.50–56.50)
|
36.50(28.00–58.00)
|
0.9253
|
Albumin, g/L
|
40–55
|
34.50 (31–38)
|
37 (32-39.50)
|
33 (30–36)
|
0.0162
|
33.50(33.00–37.00)
|
32.95(29.00–34.00)
|
0.7829
|
Total bilirubin, µmoll/L
|
2.00–21.00
|
9.10 (7.20–12.40)
|
9.55 (7.40–12.00)
|
9.05 (7.15–13.90)
|
0.6022
|
9.00(7.10–12.40)
|
9.90(8.00–16.00)
|
0.4138
|
Creatinine, µmol/L
|
40.00-105.00
|
69.20 (55.15–83.75)
|
63.70 (53.60–76.40)
|
72.30 (58.10–86.00)
|
0.0805
|
72.10(58.60-82.45)
|
72.30(58.10–100.00)
|
0.9977
|
Uric acid, µmol/L
|
150–430
|
253 (190–304)
|
252 (192–301)
|
256.5 (188–307)
|
0.3057
|
257(175–304)
|
256(192–380)
|
0.0535
|
Alkaline phosphatase, U/L
|
53–128
|
64.5 (51–80)
|
65 (56.5–77)
|
62.5 (49–80)
|
0.8678
|
60.5(47.5–79)
|
67.5(53–82)
|
0.2685
|
Creatine kinase, U/L
|
30–180
|
80 (45–170)
|
58 (36.5–108)
|
124 (55–231)
|
0.0031
|
96.5(48.5-245.5)
|
163.5(102–231)
|
0.4597
|
Creatine Kinase Isoenzyme-MB, U/L
|
0–25
|
11 (8–15)
|
9 (8–13)
|
12.5 (9–16)
|
0.0215
|
12(8–15)
|
13(10–16)
|
0.5757
|
Cardiac troponin T, positive No.(%)
|
NA
|
20 (16.81)
|
1 (1.67)
|
19 (32.2)
|
0.0000
|
9(21.95)
|
10(55.56)
|
0.0110
|
Lactate dehydrogenase, U/L
|
114–240
|
250.5 (195–381)
|
215 (180-265.5)
|
368 (228–458)
|
0.0000
|
361.5(213–424)
|
401.5(294–644)
|
0.0648
|
Triglyceride, mmol/L
|
0.45–1.69
|
1.225 (0.90–1.74)
|
1.17 (0.88-2.00)
|
1.32 (1-1.71)
|
0.2762
|
1.26(1.00-1.62)
|
1.49(1.09–2.15)
|
0.1530
|
Total cholesterol, mmol/L
|
2.85–5.69
|
3.895 (3.30–4.60)
|
3.92 (3.40–4.51)
|
3.745 (3.23–4.67)
|
0.7177
|
3.80(3.28–4.70)
|
3.42(3.17–4.58)
|
0.7447
|
Arterial Oxygen Saturation
|
≥ 95%
|
95 (91–98)
|
98 (97–99)
|
91 (90–92)
|
0.0000
|
92(90–93)
|
89(86–91)
|
0.0013
|
Radiological characteristics
|
|
|
|
|
|
|
|
|
Single lobe lesion of CT
|
NA
|
20 (16.67)
|
16 (27.59)
|
4 (6.45)
|
0.0020
|
3(6.82)
|
1(5.56)
|
0.8540
|
Multiple lobe lesion of CT
|
NA
|
100 (83.33)
|
42 (72.41)
|
58 (93.55)
|
|
41(93.18)
|
17(94.44)
|
|
CT lesion range
|
NA
|
40 (20–60)
|
25 (10–40)
|
50 (30–70)
|
0.0000
|
50(30–70)
|
70(50–80)
|
0.0036
|
#P values indicate differences between Nonsevere and Severe patients. |
*P values indicate differences between survival and dead patients. |
P < 0.05 was considered statistically significant. |
Table 3
Treatments and clinical outcomes of patients with Coronavirus Disease 2019
|
All patients (N = 122)
|
|
Severe patients(N = 62)
|
|
|
Non-severe (N = 60)
|
Severe (N = 62)
|
P value#
|
Survive
(N = 44)
|
Death
(N = 18)
|
P value*
|
Treatment
|
|
|
|
|
|
|
|
Intravenous antibiotics, no.(%)
|
74 (60.66)
|
19 (31.67)
|
55 (88.71)
|
0.0000
|
37(84.09)
|
18(100)
|
0.0720
|
Antiviral therapy
|
|
|
|
|
|
|
|
Arbidol
|
77 (63.11)
|
34 (56.67)
|
43 (69.35)
|
0.1460
|
30(68.18)
|
13(72.22)
|
0.7540
|
Lopinavir/Ritonavir
|
13 (10.66)
|
0 (0)
|
13 (20.97)
|
0.0000
|
5(11.36)
|
8(44.44)
|
0.0040
|
Lianhuaqingwen
|
83 (68.03)
|
45 (75)
|
38 (61.29)
|
0.1050
|
29(65.91)
|
9(50.00)
|
0.2430
|
Glucocorticoid therapy
|
41 (33.61)
|
5 (8.33)
|
36 (58.06)
|
0.0000
|
20(45.45)
|
16(88.89)
|
0.0020
|
Immunoglobulin
|
33 (27.05)
|
1 (1.67)
|
32 (51.61)
|
0.0000
|
20(45.45)
|
12(66.67)
|
0.129
|
Oxygen inhalation
|
80 (65.57)
|
33 (55.00)
|
47 (75.81)
|
0.0160
|
41(88.64)
|
8(44.44)
|
0.0010
|
Mechanical ventilation
|
|
|
|
|
|
|
|
Noninvasive
|
34 (27.87)
|
0 (0)
|
34 (54.84)
|
0.0000
|
18(40.91)
|
16(88.89)
|
0.0010
|
Invasive
|
1 (0.82)
|
0 (0)
|
1 (1.61)
|
0.323
|
0(0)
|
1(5.56)
|
0.1150
|
Prognosis
|
|
|
|
|
|
|
|
28_day_status of patients
|
|
|
|
|
|
|
|
Discharge from hospital
|
74 (60.66)
|
45 (75.00)
|
29 (46.77)
|
0.0000
|
29(65.91)
|
0(0)
|
0.0000
|
Death
|
17 (13.93)
|
0 (0)
|
17 (27.42)
|
|
0(0)
|
17(94.44)
|
|
Inpatient treatment
|
31 (25.41)
|
15 (25.00)
|
16 (25.81)
|
|
15(34.09)
|
1(5.56)
|
|
ICU admission
|
46 (37.70)
|
1 (1.67)
|
45 (72.58)
|
0.0000
|
27(61.36)
|
18(100)
|
0.0020
|
#P values indicate differences between Nonsevere and Severe patients. |
*P values indicate differences between survival and dead patients. |
P < 0.05 was considered statistically significant. |
In addition, patients with severe disease had more abnormal laboratory parameters than non-severe cases, including higher cardiac troponin T(cTnT),aspartate aminotransferase (AST), albumin, creatine kinase (CK) and lactate dehydrogenase (LDH) but lower arterial oxygen saturation (SaO2). On the evidence of our result, the concentration of hemoglobin (Hb), alanine aminotransferase (ALT), total bilirubin (TB), triglyceride (TG), total cholesterol (TC) and alkaline phosphatase (AP) weren't significantly correlated with severity. Concerning radiographic presentations, we found more (93.55%) patients in severe group on admission revealed multiple lobe lesion. Furthermore, lesion range in CT image also larger in severe group. The same laboratory index and radiological characteristic were repeatedly analyzed purely in patients developing severe. Of note, only four laboratory parameters indicated the association with death, including cTnT value(P = 0.011), leukocyte count (P = 0.0015), neutrophil count(P = 0.0011) and SaO2(P = 0.0013). Apart from it, the larger lesion ranges on CT scan also predicted the fatal outcome.
Treatment and Clinical Outcomes
Most cases received intravenous antibiotics therapy (60.66%), and many received antiviral therapy (Arbidol, 63.11%; Lopinavir/ritonavir, 10.66%). Glucocorticoid therapy was given to 41 patients, with a higher percentage among those patients in severe group. Glucocorticoid use also occupied a higher proportion among non-survivors than survivors. But whether the severe condition needs glucocorticoid therapy or the side effect of it contribute to the poor prognosis were unclear. The complex causal relationship has to be further studied. Mechanical ventilation was required in 34 patients, all of whom were coming from severe group. During our study, the primary end point event all occurred in 17 severe patients. Eventually, in survival group, 29(65.91%) patients were discharged from hospital on 28th day compared to none in non-survival group. Fifteen of 44 (34.09%) patients in survival group continued the inpatient therapy. There is no doubt that all of the subjects who died had transferred into ICU for continue therapy.
The dynamic change of lymphocyte after admission to hospital in severe group
The result in Table 1 inferred that lymphocyte could help recognize the patients with severe disease. To determine the role of white blood cell especially lymphocyte in COVID-19, we dynamically observed the change of lymphocyte value from the first day to the 27th day after the admission to hospital among patients suffered from severe disease (Fig. 2). On one hand, non-survivors developed severe lymphopenia compared to survivors during hospitalization. On the other hand, it was illustrated that lymphocyte gradually showed a wavelike decrease change until death occurred among non-survivors even with treatment. Over all it implicated that lymphopenia may be a good indicator of poor prognosis.
Analysis of 28-day mortality in all and severe subjects
Binary cox regression model was performed to figure out the factors in strong relation with 28-day mortality. The results of the model were summarized in S2 and S3. In accordance with the results before, certain factors (cTnT value, leukocyte count, neutrophil count and SaO2 were statistically significantly related to 28-day mortality in severe subjects (S2). In addition to the parameters mentioned above, respiratory rate and lymphocyte were manifested to be associated with 28-day mortality in all subjects(S3). On the basis of cox regression analysis result in severe (Fig. 3B) and all (Fig. 3A) inpatients were respectively demonstrated in forest plot. No matter the target population was, we found that cTnT was the strongest risk factor(P < 0.05), compared to leukocyte count, neutrophil count and CT performance. High SaO2 was a protective factor. In the entire cohort, patients with lymphocytosis also showed a favorable survival status on 28th day. At last, survival curves were constructed based on the result of cox regression analysis to investigate promising parameter with predictive value (Fig. 4). The abnormal cTnT or neutrophil group appeared to have a lower survival curve than the normal group did.