Table 1
Baseline clinical characteristics of COVID-19accordingto age groups
|
Total
|
<30
|
≥30,<40
|
≥40,<50
|
≥50,<65
|
≥65
|
P value
|
|
n=299
|
n=41
|
n=75
|
n=74
|
n=69
|
n=40
|
|
Age [y]
|
44(34,54)
|
25(22,28.5)
|
34(32,37)
|
45(42,47)
|
54(52,59)
|
74.5(67,80)
|
0.000**
|
Sex [% male]
|
158(53%)
|
27(66%)
|
42(56%)
|
43(58%)
|
30(43%)
|
16(40%)
|
0.061
|
Weight [kg]
|
65(56,74)
|
68(53,77.5)
|
65(54,75)
|
66(58,75)
|
64(60,70)
|
59(50,61)
|
0.043*
|
Height [cm]
|
164(158,170)
|
170(160,175)
|
166(160,172)
|
168(158,170)
|
160(156.5,166.5)
|
158(156,164.5)
|
0.000**
|
BMII [kg/m2]
|
23.38(21.63,26.08)
|
22.34(20.05,26.8)
|
23.13(20.96,25.16)
|
23.63(22.38,26.22)
|
24.06(22.86,26.37)
|
22.21(20.36,24.52)
|
0.063
|
Total number of chronicdisease
|
0(0,1)
|
0(0,0)
|
0(0,0)
|
0(0,1)
|
0(0,1)
|
1(1,2)
|
0.000**
|
Temp [ºC]
|
36.75(36.5,37.2)
|
37(36.7,37.3)
|
36.8(36.5,37.2)
|
36.7(36.5,37.23)
|
36.6(36.4,37.1)
|
36.6(36.43,37)
|
0.026*
|
HR [min-1]
|
86(78,96)
|
87.5(83.5,100)
|
82(76,95.25)
|
85(77.5,92)
|
88.5(82,98)
|
90(78.25,99)
|
0.036*
|
R [min-1]
|
20(20,20)
|
20(18,20)
|
20(19.75,20)
|
20(19.75,20)
|
20(20,20)
|
20(20,21)
|
0.025*
|
chronicdisease
|
105(35%)
|
2(5%)
|
12(16%)
|
25(34%)
|
36(52%)
|
30(75%)
|
0.000**
|
DM
|
35(12%)
|
1(2%)
|
4(5%)
|
7(9%)
|
10(14%)
|
13(33%)
|
0.000**
|
HBP
|
53(18%)
|
0(0%)
|
2(3%)
|
12(16%)
|
16(23%)
|
23(58%)
|
0.000**
|
Chronic heart disease
|
14(5%)
|
0(0%)
|
1(1%)
|
2(3%)
|
6(9%)
|
5(13%)
|
0.013*
|
Chronic pulmonary disease
|
17(6%)
|
1(2%)
|
2(3%)
|
1(1%)
|
9(13%)
|
4(10%)
|
0.011*
|
Cancer
|
5(2%)
|
0(0%)
|
0(0%)
|
2(3%)
|
2(3%)
|
1(3%)
|
0.549
|
Chronicnervous system disease
|
8(3%)
|
0(0%)
|
2(3%)
|
0(0%)
|
4(6%)
|
2(5%)
|
0.147
|
Chronic liver disease
|
8(3%)
|
0(0%)
|
3(4%)
|
4(5%)
|
1(1%)
|
0(0%)
|
0.265
|
Chronic kidney disease
|
1(0%)
|
0(0%)
|
0(0%)
|
0(0%)
|
0(0%)
|
1(3%)
|
0.134
|
Endocrine and immune disease
|
5(2%)
|
0(0%)
|
1(1%)
|
2(3%)
|
1(1%)
|
1(3%)
|
0.878
|
Bilateral involvement on chest radiographs
|
236(79%)
|
25(61%)
|
55(73%)
|
61(82%)
|
59(86%)
|
36(90%)
|
0.005**
|
Epidemiological history
|
|
|
|
|
|
|
|
Imported case
|
117(39.13%)
|
15(36.59%)
|
40(53.33%)
|
37(50%)
|
25(36.23%)
|
0(0%)
|
0.000**
|
Secondary case
|
111(37.12%)
|
18(43.9%)
|
20(26.67%)
|
22(29.73%)
|
29(42.03%)
|
22(55%)
|
|
Other case
|
71(23.75%)
|
8(19.51%)
|
15(20%)
|
15(20.27%)
|
15(21.74%)
|
18(45%)
|
|
* p<0.05, **p<0.01 |
Symptoms
The most common symptoms were cough in 216 (72%) patients, fever in 202 (68%), expectoration in 139 (46%), fatigue in 117 (39%), dry cough in 77 (26%) and were of comparable prevalence in all age groups. Only dyspnea was significantly different between elderly group and other groups (p=0.001) (Supplement Figure 2a).
Comparison of laboratory testing profile
Hemoglobin (Hb) and albumen levels (Supplement Table 1) fell with increasing age: Hb 146,140,141,126 and 122g/l in<30, 30-40, 40-50, 50-65 and ≥65 y age groups, respectively;p=0.000; and albumin 42.25, 45.36,45.36, 42.6, 40.9 and 36.92 g/l in<30, 30-40, 40-50, 50-65 and ≥65 age groups, respectively;p=0.000).
Patients age ≥65 had significantly higher neutrophil percentage compared to age<30 (69.25% vs. 57.8%, p=0.002). Age ≥65 had significant lower lymphocyte percentage compared to age<30 and age 30-40 (19.25 vs. 32.75, p=0.003; 19.25 vs. 29.1, p=0.015). Age<30had significantly higher levels of lymphocyte counts compared to age 30-40, 40-50, 50-65,≥65(1.6 vs. 1.2, p=0.009; 1.6 vs. 1.15, p=0.002; 1.6 vs. 1.29, p=0.021; 1.6 vs. 1.06, p< 0.001). The level of ESR and PCT of age ≥65 were the highest among all groups; these values were higher than level of ESR and PCTof age<30, 30-40, 40-50 and 50-65 with statistically significant differences (p< 0.001). Age≥65had significantly higher levels of CRP compared to age 30-40 (13.9 vs. 0.5, p=0.002). The increased inflammation as reflected by increased ESR and PCT and decreased immune function as reflected by decreased lymphocytecounts suggesting that there may be more inflammatory factor storm and immune dysfunction with increasing age groups.
Measurements such as BUN (5.12 vs. 3.82, p=0.008; 5.12 vs. 3.7, p=0.001; 5.12 vs. 3.7, p=0.018) and Mb(86.25 vs. 37.35, p=0.006; 86.25 vs. 35, p=0.007; 86.25 vs. 33.5, p=0.004)of age≥65were significantly higher than those of age<30, 30-40 and 40-50.
In addition, levels of DD of age ≥65 was significantly higher than those of age<30, 30-40 and 40-50 and 50-65 (0.66 vs. 0.29, p< 0.001;0.66 vs. 0.28, p< 0.001; 0.66 vs. 0.31, p< 0.001; 0.66 vs.0.35, p< 0.001). Levels of plateletsof age ≥65 and 50-65 was significantly lower than those of age<30(175.5 vs. 245, p=0.037;184 vs. 245, p=0.019)(Supplement Table 1 and Figure 1). These changes suggesting potentially heart, kidney and coagulation function damagein the oldest age group. The levels of WBC,N,PT time, APTT,AST,CK,CKMB,TBIL, K,Na,Cr,LDH, and Glu of the groups were not statistically different among different age groups.
Medical treatments and outcomes of COVID-19 among the age groups
80% received Interferon alpha inhalation (239/299),76%of the patients received Lopinavir/ritonavir (228/299),57%receivedArbidol(169/299), and65.22% receivedLianhua Qingwen Capsule treatment (chinese medicine). Combination use of Arbidol, Lopinavir/ritonavir or Interferon alpha inhalation was also common. Empirical antibiotic treatment was used when bacterial infection was suspected, which may reference for elevated Neu, PCT value and sputum. 42%were received antibiotic (126/299). Percentage of corticosteroid (17/57, 43%) and gamma globulin (19/56, 48%) treatment was highest in age ≥65.
In particular, mild type accounted for10.7% (32/299), moderate type accounted for 77.26% (75/299), severe type accounted for 8.7% (10/299), critical type accounted for 3.34% (4/299).Proportion of severe or critical type was 2.44%, 5.33%, 9.46%, 14.49%, and 35%in patients with age<30, 30-40, 40-50, 50-65, ≥65, respectively (p < 0.001). Proportion of mild or moderatetype was 97.56%, 94.67%,90.54%, 85.51%, and65% in patients with age<30 30-40, 40-50, 50-65, ≥65. The medium time from onset treatment to throat swab turn negative was 15.5 days in age ≥65, 16 days in age 50-65, and 11 days in age<30, 10 days in 30-40, 11.5 days in 40-50.
At this point, ICU admissionrate was 0%, 4%, 3%, 4% and 18% in age<30, 30-40, 40-50, 50-65, ≥65 (p = 0.003). ARDSrate was 0%, 4%, 7%, 9% and 30% in age<30, 30-40, 40-50, 50-65, ≥65 (p < 0.001). Rate of shock was 0%, 1%, 1%, 0% and 10% in age<30, 30-40, 40-50, 50-65, ≥65 (p = 0.006). 285 patients (95.32%)were cured and discharged, 12 patients (4.01%) was still on medical treatment in hospital, 2 patients (0.67%) died because of respiratory failure (p < 0.001).On medical treatment rate was 0%,1.33%, 2.7%,2.9% and 17.5% in age<30, 30-40, 40-50, 50-65, ≥65. There were no difference in time from symptom onset to initial treatment and hospitalizationdays among age groups (Supplement Table 1).
Comparison of clinical characteristics of COVID-19 between mild/moderate type and severe/critical type
Patients developed to severe or critical type were older than patients with mild or moderate type (57.72 vs. 44.06p=0.002).Comparison were performed to determine factors associated with severe or critical type in overall COVID-19 patients. Patients developed to severe or critical type have higher percentage of cough (94.44% vs. 69.2%, p=0.004), fever(88.89% vs. 64.64%, p=0.002), expectoration(63.89% vs. 44.11%, p=0.026), fatigue (61.11% vs. 36.12%, p=0.004), dyspnea(58.33% vs. 8.37%, p< 0.001), and hemoptysis(8.33% vs. 0.76%, p=0.014) symptom than patients with mild or moderate type(Supplement Figure 2b).
In general, patients developed to severe or critical type have higher percentage with at least one chronic disease (77.78% vs. 29.28%, p< 0.001), DM(30.56% vs. 9.13%, p =0.001), chronic heart disease(22.22%vs. 2.28%, p< 0.001) and chronic pulmonary disease(16.67% vs. 4.18%, p =0.009)compared to patients with mild or moderate type. Imported and secondary case accounts for 40.68% and 38.40% in patients with mild or moderate type, however, this proportion was 27.78% and 27.78% in severe or critical type. Noticing that 44.44% of severe or critical type was infected with unknown origin of infected.
Besides, relatively high percent of drugs was prescribed in severe or critical type than mild or moderate type. Obviously, severe or critical type have longer hospitalizationdays (20.89 vs.17.18, p =0.011), higher rate of ICU admission (25% vs. 2.28%, p< 0.001), ARDS (52.78% vs. 2.66%, p< 0.001), and shock (13.89% vs.0.38%, p< 0.001) than mild or moderate type. Still on medical treatment rate was 19.44% in severe or critical type and 3.07% in mild or moderate type. In-hospital death cases were 2 in severe or critical type and none in mild or moderate type. However, there was no significant difference regarding sex, BMI, temperature in admission,bilateral involvement on chest radiographs, other onset symptoms and time from symptom onset to initial treatment and time from onset treatment to throat swab turn negative between severe or critical type and mild or moderate type(Table 3).
Factors for severe or critical type inCOVID-19 patients
In a binary logistic regression analysis, eight factors (age, HR in admission, R in admission, history of DM, HBP, chronic heart disease, chronic lung disease, epidemiological history) were included as covariates.We found old age (OR 1.055, 95% CI 1.016-1.095, p= 0.006), HR in admission (OR 1.085, 95% CI 1.03-1.144, p = 0.002), R in admission (OR 1.635, 95% CI 1.093-2.431, p = 0.017), and history of chronic heart disease (OR 56.038, 95% CI 2.764-1136.053, p = 0.009) showed independent associations with severe or critical type (Table 4).
Table 2
Medical treatments and outcomes of COVID-19 among the age groups
|
Total
|
<30
|
≥30,<40
|
≥40,<50
|
≥50,<65
|
≥65
|
P value
|
|
n=299
|
n=41
|
n=75
|
n=74
|
n=69
|
n=40
|
|
Hospitalizationdays
|
17(12,23.5)
|
16(11.25,20.75)
|
15(11,21)
|
16(10,22.25)
|
18(13,25.5)
|
17(12,24)
|
0.189
|
TreatmentNegative
|
13(9,19)
|
11.5(8,18)
|
10(7,18)
|
11(8,18.5)
|
16(10,22)
|
15.5(10,21)
|
0.009**
|
TreatmentNegativeE
|
15(9,21)
|
14(9.25,20.5)
|
11.5(7.75,19)
|
14(7.5,21)
|
18(12,23)
|
17(11,22)
|
0.015*
|
Onsettreatment
|
4(1,6)
|
3(1,5)
|
3(1,7)
|
4(1.75,7)
|
4(2,6.75)
|
3(1,6.5)
|
0.687
|
Arbidol+Lopinavir/ritonavir+Interferon alpha inhalation
|
120(40%)
|
13(32%)
|
28(37%)
|
29(39%)
|
32(46%)
|
18(45%)
|
0.558
|
Arbidol+Lopinavir/ritonavir
|
134(45%)
|
15(37%)
|
30(40%)
|
34(46%)
|
36(52%)
|
19(48%)
|
0.479
|
Arbidol+Interferon alpha inhalation
|
141(47%)
|
16(39%)
|
32(43%)
|
32(43%)
|
40(58%)
|
21(53%)
|
0.211
|
Lopinavir/ritonavir+Interferon alpha inhalation
|
189(63%)
|
24(59%)
|
47(63%)
|
47(64%)
|
45(65%)
|
26(65%)
|
0.966
|
Arbidol
|
169(57%)
|
19(46%)
|
37(49%)
|
42(57%)
|
46(67%)
|
25(63%)
|
0.148
|
Lopinavirritonavir
|
228(76%)
|
30(73%)
|
56(75%)
|
60(81%)
|
54(78%)
|
28(70%)
|
0.683
|
Interferonalphainhalation
|
239(80%)
|
34(83%)
|
58(77%)
|
55(74%)
|
58(84%)
|
34(85%)
|
0.498
|
LianhuaQingwenCapsule
|
155(52%)
|
21(51%)
|
38(51%)
|
39(53%)
|
29(42%)
|
28(70%)
|
0.091
|
Antibiotics
|
126(42%)
|
13(32%)
|
28(37%)
|
30(41%)
|
31(45%)
|
24(60%)
|
0.089
|
Corticosteroid
|
57(19%)
|
3(7%)
|
11(15%)
|
12(16%)
|
14(20%)
|
17(43%)
|
0.001
|
gammglobulin
|
56(19%)
|
2(5%)
|
6(8%)
|
15(20%)
|
14(20%)
|
19(48%)
|
0.000**
|
Severity
|
|
|
|
|
|
|
|
Mild
|
32(10.7%)
|
5(12.2%)
|
11(14.67%)
|
10(13.51%)
|
5(7.25%)
|
1(2.5%)
|
|
Moderate
|
231(77.26%)
|
35(85.37%)
|
60(80%)
|
57(77.03%)
|
54(78.26%)
|
25(62.5%)
|
|
Severe
|
26(8.7%)
|
1(2.44%)
|
3(4%)
|
4(5.41%)
|
10(14.49%)
|
8(20%)
|
|
Critical
|
10(3.34%)
|
0(0%)
|
1(1.33%)
|
3(4.05%)
|
0(0%)
|
6(15%)
|
|
Severity
|
|
|
|
|
|
|
|
Mild or moderate
|
263(87.96%)
|
40(97.56%)
|
71(94.67%)
|
67(90.54%)
|
59(85.51%)
|
26(65%)
|
0.000**
|
Severe or critical
|
36(12.04%)
|
1(2.44%)
|
4(5.33%)
|
7(9.46%)
|
10(14.49%)
|
14(35%)
|
|
ICU
|
15(5%)
|
0(0%)
|
3(4%)
|
2(3%)
|
3(4%)
|
7(18%)
|
0.003**
|
ARDS
|
26(9%)
|
0(0%)
|
3(4%)
|
5(7%)
|
6(9%)
|
12(30%)
|
0.000**
|
SHOCK
|
6(2%)
|
0(0%)
|
1(1%)
|
1(1%)
|
0(0%)
|
4(10%)
|
0.006**
|
Outcome
|
|
|
|
|
|
|
|
Cured and discharged
|
285(95.32%)
|
41(100%)
|
74(98.67%)
|
72(97.3%)
|
67(97.1%)
|
31(77.5%)
|
0.000**
|
On medical treatment in hospital
|
12(4.01%)
|
0(0%)
|
1(1.33%)
|
2(2.7%)
|
2(2.9%)
|
7(17.5%)
|
|
In-hospital death events
|
2(0.67%)
|
0(0%)
|
0(0%)
|
0(0%)
|
0(0%)
|
2(5%)
|
|
* p<0.05, **p<0.01 |
Table 3
Comparison of clinical characteristics of COVID-19 between mild or moderate type and severe or critical type
|
Mild or moderate
|
Severe or critical
|
P value
|
|
n=263
|
n=36
|
|
Age
|
44.06±14.81
|
57.72±15.5
|
0.000**
|
Sex
|
135(51.33%)
|
23(63.89%)
|
0.157
|
Weight
|
50.25±29.43
|
107.57±221.5
|
0.13
|
Height
|
138.14±50.22
|
114.33±55.11
|
0.018*
|
BMI
|
23.77±3.8
|
24.02±3.03
|
0.708
|
Total number of chronicdisease
|
0(0,1)
|
1(1,2)
|
0.000**
|
Temp
|
36.7(36.5,37.1)
|
36.9(36.5,37.65)
|
0.133
|
HR
|
86.38±11.28
|
97.41±10.34
|
0.000**
|
R
|
20(19,20)
|
20(20,22)
|
0.000**
|
Chronicdisease
|
77(29.28%)
|
28(77.78%)
|
0.000**
|
DM
|
24(9.13%)
|
11(30.56%)
|
0.001**
|
HBP
|
37(14.07%)
|
16(44.44%)
|
0.000**
|
Chronic heart disease
|
6(2.28%)
|
8(22.22%)
|
0.000**
|
Chronic pulmonary disease
|
11(4.18%)
|
6(16.67%)
|
0.009**
|
Cancer
|
4(1.52%)
|
1(2.78%)
|
1
|
Chronicnervous system disease
|
6(2.28%)
|
2(5.56%)
|
0.248
|
Chronic liver disease
|
5(1.9%)
|
3(8.33%)
|
0.059
|
Chronic kidney disease
|
0(0%)
|
1(2.78%)
|
0.12
|
Endocrine and immune disease
|
4(1.52%)
|
1(2.78%)
|
1
|
Bilateral involvement on chest radiographs
|
204(77.57%)
|
32(88.89%)
|
0.118
|
Epidemiological history
|
|
|
|
Imported case
|
107(40.68%)
|
10(27.78%)
|
0.008**
|
Secondary case
|
101(38.40%)
|
10(27.78%)
|
|
Other case
|
55(20.91%)
|
16(44.44%)
|
|
Hospitalizationdays
|
17.18±7.83
|
20.89±9.28
|
0.011*
|
TreatmentNegative
|
14.23±8.27
|
16.29±6.83
|
0.161
|
TreatmentNegativeE
|
15.43±8.48
|
17.64±6.95
|
0.242
|
Onsettreatment
|
4.68±4.37
|
5.67±4.74
|
0.209
|
ICU
|
6(2.28%)
|
9(25%)
|
0.000**
|
ARDS
|
7(2.66%)
|
19(52.78%)
|
0.000**
|
SHOCK
|
1(0.38%)
|
5(13.89%)
|
0.000**
|
Outcome
|
|
|
0.000**
|
Cured and discharged
|
258(98,10%)
|
27(75%)
|
0.000**
|
On medical treatment in hospital
|
5(1,9%)
|
7(19.44%)
|
|
In-hospital death events
|
0(0%)
|
2(5.56%)
|
|
ALI
|
97(36.88%)
|
23(63.89%)
|
0.002**
|
AL
|
110(41.83%)
|
24(66.67%)
|
0.005**
|
AI
|
115(43.73%)
|
26(72.22%)
|
0.001**
|
LI
|
160(60.84%)
|
29(80.56%)
|
0.021*
|
Arbidol
|
141(53.61%)
|
28(77.78%)
|
0.006**
|
Lopinavirritonavir
|
197(74.9%)
|
31(86.11%)
|
0.138
|
Interferonalphainhalatio
|
207(78.71%)
|
32(88.89%)
|
0.153
|
LianhuaQingwenCapsule
|
130(49.43%)
|
25(69.44%)
|
0.024*
|
Antibiotics
|
95(36.12%)
|
31(86.11%)
|
0.000**
|
Corticosteroid
|
32(12.17%)
|
25(69.44%)
|
0.000**
|
gammglobulin
|
29(11.03%)
|
27(75%)
|
0.000**
|
* p<0.05, **p<0.01 |
Table 4
Binary logistic regression analysis of factors for severe or critical type in COVID-19
|
B
|
Standard error
|
Wald
|
P value
|
Exp(B)
|
95% CI
|
Age
|
0.053
|
0.019
|
7.695
|
0.006
|
1.055
|
1.016-1.095
|
HR
|
0.082
|
0.027
|
9.416
|
0.002
|
1.085
|
1.03-1.144
|
R
|
0.488
|
0.204
|
5.733
|
0.017
|
1.63
|
1.093-2.431
|
Heart
|
4.026
|
1.535
|
6.876
|
0.009
|
56.038
|
2.764-1136.053
|
Constant
|
-22.634
|
5.175
|
19.125
|
0
|
0
|
|
CI, Confidence Interval.
* p<0.05, **p<0.01 |