Demographics, characteristics, and clinical outcomes
From 26 January to 1 April 2020, 338 patients with COVID-19 confirmed by laboratory findings or otherwise clinical diagnosis were treated at the two hospitals in Hubei province of China. We included 333 patients, of which 65 subjects developed ARDS, and we excluded 5 cases due to negative/no laboratory testing or insufficient data. The details of enrolment are provided in Fig. 1.
Compared with patients without ARDS, patients with ARDS were older (P < 0.001) and trended higher BMI (P = 0.055), and more patients with ARDS were over 65 years (P = 0.015) and males (P = 0.008) (Table 1). Median days from symptoms onset to hospital admission were shorter in ARDS than non-ARDS patients (P = 0.012). However, more patients with ARDS presented with initial symptoms of fever (P = 0.028), cough (P = 0.009), fatigue (P = 0.050), expectoration (P < 0.001), palpitation and chest distress (P < 0.001), and at least three symptoms (P < 0.001) compared with those who did not develop ARDS. Patients who progressed into ARDS had higher breath rate (P = 0.008), more comorbidities (P = 0.008), and severest pneumonia graded by physicians (P = 0.008) on admission than patients not progressing into ARDS. All subjects were found to have bilateral infiltrate in lung in the severe illness of COVID-19 compared to 15.2% in the non-severe patients (P < 0.001). For treatment, the significantly higher percentages of patients with ARDS received general or advanced therapies, including antivirus therapy (P = 0.002), antibiotic (P < 0.001), glucocorticoid (P < 0.001), ICU-level care (P < 0.001), prone positioning (P < 0.001), CRRT (P < 0.001), and ECMO (P < 0.001). At last, when compared with patients who did not happen ARDS, patients with the severe illness further progressed more on IMV due to failure of noninvasive respiratory support (P < 0.001), stayed longer in hospital (P = 0.012), and died more (P < 0.001). No patient in non-ARDS group occurred severe complications compared to the 13 in ARDS group had acute respiratory failure (P < 0.001) and acute circulatory failure (P < 0.001), and the 7 occurred Shock/MODS (P < 0.001).
Table 1
Characteristics and outcomes between COVID-19 patients with ARDS and without ARDS and between the ARDS subgroup of intubation and never intubation
Study variables
|
All patients
Value, no./total no. (%) or median (IQR) (n = 333)
|
Patients with ARDS
Value, no./total no. (%) or median (IQR) (n = 65)
|
|
Without ARDS
(n = 268)
|
With ARDS
(n = 65)
|
P value
|
Intubation
(n = 20)
|
Never Intubation
(n = 45)
|
P value
|
Age
|
|
|
|
|
|
|
median, IQR
|
59.0 (43.0–68.0)
|
67.0 (56.0–78.0)
|
< 0.001
|
71.5 (65.5–79.5)
|
61.0 (55.0–77.0)
|
0.094
|
≥ 65 years
|
100/268 (37.3%)
|
35/65 (53.8%)
|
0.015
|
15/20 (75.0%)
|
19/45 (42.2%)
|
0.015
|
Male sex
|
141/268 (37.3%)
|
46/65 (70.8%)
|
0.008
|
12/20 (60.0%)
|
34/45 (75.6%)
|
0.203
|
BMI*
|
|
|
|
|
|
|
median, IQR
|
23.4 (21.5–25.5)
|
24.4 (22.4–26.7) (n = 52)
|
0.055
|
23.5 (21.5–27.2) (n = 18)
|
24.6 (23.4–26.7) (n = 32)
|
0.538
|
≥ 25
|
86/268 (32.1%)
|
21/52 (40%)
|
0.246
|
7/18 (38.9%)
|
13/32 (40.6%)
|
0.904
|
Smoke history
|
22/268 (8.2%)
|
7/65 (10.8%)
|
0.511
|
2/20 (10%)
|
5/45 (11.1%)
|
1.000
|
Alcohol used
|
23/268 (8.6%)
|
9/65 (13.8%)
|
0.196
|
1/20 (5%)
|
8/45 (17.8%)
|
0.255
|
Days from symptoms onset to hospital admission (median, IQR)
|
10.0 (5.0–15.0)
|
8.0 (5.0–10.0)
|
0.012
|
7.5 (5.0–10.0)
|
9.0 (5.0–11.0)
|
0.383
|
Initial symptoms
|
|
|
|
|
|
|
Fever
|
191/268 (71.3%)
|
55/65 (84.6%)
|
0.028
|
18/20 (90.0%)
|
37/45 (82.2%)
|
0.711
|
Cough
|
142/268 (53.0%)
|
46/65 (70.8%)
|
0.009
|
15/20 (75.0%)
|
31/45 (68.9%)
|
0.617
|
Short of breath
|
142/268 (53.0%)
|
27/65 (41.5%)
|
0.098
|
12/20 (60.0%)
|
17/45 (37.8%)
|
0.096
|
Fatigue
|
56/268 (20.9%)
|
21/65 (32.3%)
|
0.050
|
11/20 (55.0%)
|
10/45 (22.2%)
|
0.009
|
Expectoration
|
41/268 (15.3%)
|
17/65 (26.2%)
|
< 0.001
|
7/20 (35.0%)
|
10/45 (22.2%)
|
0.279
|
Palpitation and chest distress
|
23/268 (8.6%)
|
17/65 (26.2%)
|
< 0.001
|
7/20 (35.0%)
|
10/45 (22.2%)
|
0.279
|
Number of complaints ≥ 3
|
113/268 (42.2%)
|
44/65 (67.7%)
|
< 0.001
|
18/20 (90.0%)
|
26/45 (57.8%)
|
0.011
|
Vital signs on admission fever (≥ 37.2℃)
|
|
|
|
|
|
|
Breath rate (median, IQR)
|
19.0 (18.0–20.0)
|
20.0 (20.0–24.0)
|
0.008
|
20.0 (20.0–22.0)
|
21.0 (20.0–24.0)
|
0.641
|
Heart rate (median, IQR)
|
90.0 (80.0-108.0)
|
85.0 (79.0–99.0)
|
0.340
|
88.0 (80.0-106.0)
|
85.0 (79.0–96.0)
|
0.889
|
SBP (median, IQR)
|
126.5 (117.5–137.0)
|
135.0 (120.0-141.0)
|
0.249
|
145.5 (140.0-154.0)
|
124.0 (116.0-135.0)
|
0.004
|
DBP (median, IQR)
|
79.5 (70.0-87.5)
|
79.0 (71.0–86.0)
|
0.849
|
85.0 (84.0–86.0)
|
76.0 (70.0–84.0)
|
0.131
|
MAP (median, IQR)
|
96.0 (86.7–102.0)
|
99.3 (86.7–105.0)
|
0.360
|
103.5 (101.3-115.7)
|
94.7 (86.7–101.0)
|
0.021
|
Severity of pneumonia graded by physicians
|
|
|
|
|
|
|
Mild
|
28/260 (10.8%)
|
2/65 (3.1%)
|
|
0/20 (0.0%)
|
2/45 (4.4%)
|
|
Severe
|
212/260 (81.5%)
|
18/65 (27.7%)
|
|
3/20 (15.0%)
|
15/45 (33.3%)
|
|
Critical
|
20/260 (7.7%)
|
45/65 (68.3%)
|
< 0.001
|
17/20 (85.0%)
|
28/45 (62.2%)
|
0.217
|
Comorbidities
|
|
|
|
|
|
|
Hypertension
|
91/268 (40.0%)
|
20/65 (30.8%)
|
0.625
|
9/20 (45.0%)
|
11/45 (24.4%)
|
0.314
|
Diabetes
|
36/268 (13.4%)
|
10/65 (15.4%)
|
0.682
|
3/20 (25.0%)
|
7/45 (15.6%)
|
1.000
|
Brain disease
|
8/268 (3.0%)
|
6/65 (9.2)
|
0.024
|
1/20 (5.0%)
|
5/45 (11.1%)
|
0.657
|
Cardiovascular disease
|
27/268 (10.1%)
|
8/65 (12.3%)
|
0.598
|
1/20 (5.0%)
|
7/45 (15.6%)
|
0.417
|
Chronic lung disease
|
1/268 (0.38%)
|
2/65 (3.1%)
|
0.099
|
0/20 (0.0%)
|
2/45 (4.4%)
|
1.000
|
Number of coexisting disorders ≥ 1
|
12/268 (4.5%)
|
44/65 (67.7%)
|
< 0.001
|
14/20 (70.0%)
|
30/45 (66.7%)
|
0.791
|
Days from hospital admission to ARDS diagnosis (median, IQR)
|
NA
|
1.0 (0.0–4.0)
|
|
1.0 (0.0–4.0)
|
1.0 (0.0–5.0)
|
0.823
|
Days from symptoms onset to ARDS diagnosis (median, IQR)
|
NA
|
11.0 (8.0–13.0)
|
|
10.5 (6.5–12.5)
|
11.0 (8.0–15.0)
|
0.275
|
Chest imaging, bilateral infiltrate
|
40/264 (15.2%)
|
65/65 (100%)
|
< 0.001
|
20/20 (100%)
|
45/45 (100%)
|
1.000
|
Oxygenation Index on ARDS Diagnosis
|
|
|
|
|
|
|
median (IQR)
|
NA
|
182.9 (134.0-225.0)
|
|
140.8 (119.9-189.2)
|
200.0 (158.0-247.5)
|
0.004
|
300 − 200
|
NA
|
24/63 (38.1%)
|
|
4/20 (20.0%)
|
23/45 (51.1%)
|
|
199 − 100
|
NA
|
32/63 (50.8%)
|
|
12/20 (60.0%)
|
19/45 (42.2%)
|
|
< 100
|
NA
|
7/63 (11.1%)
|
|
4/20 (20.0%)
|
3/45 (6.7%)
|
0.033
|
Treatments
|
|
|
|
|
|
|
Antiviral therapy
|
220/268 (82.1%)
|
63/65(95.2%)
|
0.002
|
20/20 (100%)
|
43/45 (95.3%)
|
1.000
|
Intravenous antibiotic
|
82/268 (48.8%)
|
60/65 (92.3%)
|
< 0.001
|
20/20 (100%)
|
40/45 (88.4%)
|
0.313
|
Glucocorticoid (methylprednisolone)
|
12/268 (4.5%)
|
51/65 (7. 8.5%)
|
< 0.001
|
20/20 (100%)
|
31/45 (67.4%)
|
0.003
|
Vasopressor
|
0/268 (0.0%)
|
16/65 (24.6%)
|
< 0.001
|
10/20 (50.0%)
|
6/45 (14.0%)
|
0.002
|
Admission to ICU
|
7/268 (2.6%)
|
29/65 (44.6%)
|
< 0.001
|
15/20 (75.0%)
|
14/45 (27.9%)
|
0.012
|
Prone positioning
|
0/268 (0.0%)
|
8/65 (12.3%)
|
< 0.001
|
8/20 (40.0%)
|
0/45 (0.0%)
|
< 0.001
|
Continuous renal-replacement therapy
|
0/268 (0.0%)
|
6/65 (9.2%)
|
< 0.001
|
6/20 (30.0%)
|
0/45 (0.0%)
|
< 0.001
|
ECMO
|
0/268 (0.0%)
|
4/65 (6.2%)
|
< 0.001
|
5/20 (25.0%)
|
0/45 (0.0%)
|
0.002
|
Outcomes
|
|
|
|
|
|
|
Failure of noninvasive respiratory support†
|
0/268 (0.0%)
|
20/65 (31.7%)
|
< 0.001
|
20/20 (100%)
|
0/45 (0.0%)
|
< 0.001
|
Median ICU stay (day, IQR)‡
|
7.0 (6.0–12.0)
|
15.0 (10.0–20.0)
|
0.075
|
16.0 (10.0–21.0)
|
11.0 (4.0–16.0)
|
0.131
|
Median Hospital stay (day, IQR)
|
17.0 (12.0–24.0)
|
22.0 (13.0–34.0)
|
0.012
|
25.0 (16.0-35.5)
|
22.0 (12.0–31.0)
|
0.227
|
Death in hospital
|
0/268 (0.0%)
|
24/65 (36.9%)
|
< 0.001
|
14/20 (70.0%)
|
10/45 (22.2%)
|
< 0.001
|
Death of mild ARDS
|
NA
|
5/26 (19.2%)
|
|
3/4 (75.0%)
|
2/23(8.7%)
|
0.013
|
Death of moderate ARDS
|
NA
|
13/32 (40.6%)
|
|
7/12(58.3%)
|
6/19(31.6%)
|
0.141
|
Death of severe ARDS
|
NA
|
6/7 (85.7%)
|
|
4/4(100.0%)
|
2/3(66.7%)
|
0.429
|
Complications
|
|
|
|
|
|
|
Acute respiratory failure
|
0/268
|
13/65 (20.0%)
|
< 0.001
|
5/20 (25.0%)
|
2/45 (4.4%)
|
0.025
|
Acute circulatory failure
|
0/268
|
13/65 (20.0%)
|
< 0.001
|
7/20 (35.0%)
|
6/45 (13.3%)
|
0.044
|
Shock/MODS
|
0/268
|
7/65 (10.8%)
|
< 0.001
|
5/20 (25.0%)
|
2/45 (4.4%)
|
0.025
|
* Data regarding the BMI were missing for 28 of 333 patients (8.4%). |
† All patients first were on noninvasive oxygen support when admitted at hospital. |
‡ Data summarized from the patients admitted into ICU. |
Abbreviations: IQR, interquartile range, OI: Oxygenation Index, ECMO: Extracorporeal membrane oxygenation, MODS: Multiple Organ Dysfunction Syndrome. |
In the subgroup of COVID-19 patients with ARDS, more patients who progressed on IMV were over 65 years (P = 0.015), reported fatigue (P = 0.009) and at least three symptoms at admission (P = 0.011), and had higher SBP (P = 0.004) or MAP levels (P = 0.021) with admission fever compared with patients who were never intubated (Table 1). The median oxygenation index of intubation patients at ARDS diagnosis were 140.8 (IQR, 119.9-189.2) compared to 200.0 (IQR, 158.0-247.5) of patients without intubation (P = 0.004), and higher percentage of intubation patients presented with moderate or severe ARDS at first than patients not on intubation (P = 0.033). In addition, patients intubated were more likely to be treated with glucocorticoid (P = 0.003) and admitted into ICU (P = 0.012), and to receive prone positioning (P < 0.001), CRRT (P < 0.001), or ECMO (P = 0.002) comparing with patients not intubated during hospitalization. A higher proportion of patients intubated developed acute respiratory (P = 0.025), circulatory failure (P = 0.044), Shock/MODS (P = 0.025), and finally died in hospital (P < 0.001). The morality rate was particularly higher in the mild ARDS who received IMV (P = 0.013) than those did not.
Laboratory indices tested at admission found that compared with patients without ARDS, for patients with ARDS, the value of liver damage indices (AST P = 0.003, ALT P = 0.024, Albumin P < 0.001, A/G P < 0.001), heart injury indices (LDH and cTnI P < 0.001), pancreas injury indices (glucose P < 0.001) inflammation-related indices (ESR, CRP and PCT P < 0.001), coagulation function indices (D-Dimer, PT and INR P < 0.001), kidney dysfunction indices (CRE and GFR P < 0.001) and blood sodium levels were elevated (P < 0.001) (Table 2). However, in ARDS patients, blood cell counts of WBC (P < 0.001), neutrophil (P < 0.001) and lymphocyte (P < 0.001) and potassium levels (P = 0.041) were significantly decreased. ARDS patients demonstrated immune system destruction indicated by extremely lower median values of lymphocyte count per mm3 (670, IQR 430–1040) and multiple organ injuries suggested by abnormal median values of A/G ratio (1.13, IQR 0.95–1.39), LDH (371.5, IQR 227.0-519.0), blood glucose (7.9, IQR 6.0-10.5), and D-Dimer (0.6, IQR 0.2–2.4) levels. In the subgroup analysis, there was no significant difference of laboratory indices between the patients intubated and the patients never intubated. Nevertheless, ARDS patients on IMV trended lower cell counts of WBC, neutrophil, and lymphocyte, and elevated markers related to the damages of liver, pancreas, and kidney than the patients never intubated.
Table 2
Initial laboratory indices between COVID-19 patients with ARDS and without ARDS and between the ARDS subgroup of intubation and never intubation
Laboratory indices on admission
|
All patients
|
|
|
ARDS
|
|
|
|
Without ARDS
Value, median (IQR)
|
With ARDS
Value, median (IQR)
|
P value
|
Intubation
|
Never intubation
|
P value
|
Hematologic
|
|
|
|
|
|
|
WBC count /mm3
|
5300 (4200–6400)
|
7340 (4700–10700)
|
< 0.001
|
6450 (4350-101500.)
|
7340 (4810–11500)
|
0.418
|
Neutrophil count /mm3
|
3280 (2380–4360)
|
6320 (3440–9150)
|
< 0.001
|
5170 (3365–8985)
|
6490 (3490–10590)
|
0.706
|
Lymphocyte count /mm3
|
1260 (915–1665)
|
670 (430–1040)
|
< 0.001
|
635 (400–795)
|
740 (460–1080)
|
0.149
|
Platelet count /mm3
|
202 (157–256)
|
199 (146–236)
|
0.259
|
211 (119–223)
|
197 (154–261)
|
0.491
|
Hemoglobin, g/dL
|
12.6 (11.6–13.7)
|
13.1 (11.6–14.0)
|
0.185
|
13.0 (11.7–13.7)
|
13.2 (11.6–14.6)
|
0.367
|
Biochemical
|
|
|
|
|
|
|
TBIL, µmol/L
|
11.6 (8.6–14.9)
|
13 (10.1–18.3)
|
0.069
|
15.0 (11.1–17.7)
|
12.0 (9.8–18.3)
|
0.323
|
AST, U/L
|
27.0 (22.0-38.5)
|
39.0 (25.0–50.0)
|
0.002
|
37.5 (26.5–50.0)
|
39.0 (23.0–50.0)
|
0.793
|
ALT, U/L
|
22.0 (15.0–36.0)
|
27.0 (20.0–35.0)
|
0.024
|
25.0 (18.0–29.0)
|
28.0 (20.0–43.0)
|
0.176
|
Total protein, g/L
|
64.7 (61.2–70.5)
|
64.0 (60.7–68.3)
|
0.156
|
64.8 (63.0-68.5)
|
62.6 (59.9–68.3)
|
0.179
|
Albumin, g/L
|
39.2 (35.8–41.7)
|
34.1 (31.2–37.5)
|
< 0.001
|
34.2 (30.5–36.9)
|
34.1 (31.3–38.0)
|
0.994
|
Albumin/Globulin
|
1.49 (1.27–1.66)
|
1.13 (0.95–1.39)
|
< 0.001
|
1.13 (0.86–1.25)
|
1.16 (0.96–1.39)
|
0.344
|
LDH, unit/L
|
210.0 (171.0-266.0)
|
371.5 (227.0-519.0)
|
< 0.001
|
384.0 (218.0-519.0)
|
361.0 (241.0-525.0)
|
0.927
|
cTnI, ng/mL*
|
0.01 (0.01–0.01)
|
0.02 (0.01–0.04)
|
< 0.001
|
0.02 (0.01–0.03)
|
0.01 (0.01–0.06)
|
0.953
|
Glucose, mmol/L†
|
5.8 (5.2–6.7)
|
7.9 (6.0-10.5)
|
< 0.001
|
7.8 (6.1–10.2)
|
7.9 (6.0-10.7)
|
0.739
|
Creatinine, µmol/L
|
65.0 (53.0–76.0)
|
74.2 (59.0–93.0)
|
< 0.001
|
74.4 (66.5-107.5)
|
74.2 (57.0-92.5)
|
0.685
|
GFR, ml/min/1.73m2
|
100.0 (89.0-113.0)
|
89.0 (62.0-104.0)
|
< 0.001
|
72.5 (60.0-94.5)
|
93.0 (68.0-108.0)
|
0.120
|
Potassium, mmol/L‡
|
3.8 (3.5–4.1)
|
3.9 (3.7–4.3)
|
0.041
|
4.0 (3.7–4.1)
|
3.9 (3.6–4.3)
|
0.967
|
Sodium, mmol/L‡
|
140.6 (138.8-142.3)
|
137.8 (134.8-139.3)
|
< 0.001
|
137.6 (135.0-139.3)
|
137.9 (134.8-139.3)
|
0.882
|
D-Dimer, mg/L
|
0.1 (0.1–0.3)
|
0.6 (0.2–2.4)
|
< 0.001
|
0.4 (0.2–2.3)
|
0.7 (0.2–2.4)
|
0.776
|
PT, s§
|
11.8 (11.3–12.6)
|
13.1 (11.9–14.7)
|
< 0.001
|
13.1 (11.7–13.9)
|
13.2 (12.2–14.8)
|
0.339
|
INR
|
1.1 (1.0-1.2)
|
1.1 (1.1–1.2)
|
< 0.001
|
1.2 (1.1–1.2)
|
1.1 (1.1–1.2)
|
0.438
|
ESR, mm/h||
|
22.0 (11.0–50.0)
|
62.5 (31.0–81.0)
|
< 0.001
|
66.5 (30.5–84.5)
|
60.5 (39.0–80.0)
|
0.832
|
C-Reactive Protein, mg/L
|
10.0 (3.5–26.3)
|
59.1 (20.1-108.6)
|
< 0.001
|
72.0 (38.2-110.6)
|
48.2 (19.5-108.6)
|
0.410
|
Procalcitonin, µg/L
|
0.04 (0.03–0.07)
|
0.12 (0.05–0.38)
|
< 0.001
|
0.21 (0.07–0.50)
|
0.10 (0.05–0.35)
|
0.438
|
* Data regarding the cTnI were missing for 2 ARDS patients who were never intubated. |
† Data regarding the Glucose were missing for 1 ARDS patient who were never intubated. |
‡ Data regarding both the Potassium and Sodium were missing for 6 ARDS patients, with 4 at never intubation group, 1 at early intubation group, and 1 at late intubation group. |
§ Data regarding the PTs were missing for 1 ARDS patient who were never intubated. |
|| Data regarding the ESR were missing for 6 ARDS patients who were never intubated. |
Abbreviations: IQR, interquartile range, WBC: White Blood Cell; TBIL: Total bilirubin, AST: aspartate transaminase, ALT: alanine aminotransaminase, LDH: lactate dehydrogenase, GFR: glomerular filtration rate, PT: prothrombin time, INR: international normalized ratio, ESR: Erythrocyte Sedimentation Rate. |
High mortality of COVID-19 ARDS patients with intubation and the initial time of intubation
COVID-19 ARDS patients requiring intubation showed a high mortality at 70.0% (Table 1). However, we found the survivors had been intubated earlier since ARDS diagnosis than the non-survivors, with a median of 5.5 and IQR of 4.0–7.0 days versus a median of 11.5 and IQR 6.0–14.0 days (P < 0.001) (Fig. 2).
Risk factors associated with ARDS and intubation/death in COVID-19 patients
Univariate cox proportion hazard models showed that age and age over 65 years were associated with the development of ARDS (HR, 1.04; 95% CI, 1.01–1.06, HR, 2.24; 95% CI, 1.18–4.28) and the intubation/death (HR, 1.03; 95% CI, 1.01–1.06, HR, 3.07; 95% CI, 1.32–7.16) (Table 3). Other factors including male gender and abnormal laboratory indices related to the development of ARDS were not found to be associated with the intubation/death. However, the number of symptom complaints equal and more than three was associated with higher likelihood of progressing into intubation/death (HR, 4.74; 95% CI, 1.65–13.66). Patients on lower OI ratio at ARDS diagnosis (HR, 0.99; 95% CI, 0.98-1.00) and patients with OI ratio less than 200 (HR, 3.05; 95% CI, 1.24–7.46), 150 (HR, 3.00; 95% CI, 1.45–6.17), or 100 (HR, 2.54; 95% CI, 1.03–6.25) were more likely to require intubation or die in hospital. Sensitivity analysis showed that when adjusting for age and gender, COVID-19 patients with lymphocyte count of < 1000 per mm3 at admission were still significantly associated with developing ARDS (HR, 4.10; 95% CI, 2.40–7.10). When adjusting for age, ARDS patients with lower OI ratio less than 150 at ARDS diagnosis were also more likely to need the intubation or happen the death (HR, 2.50; 95% CI, 1.17–5.30) (Table S1).
Table 3
Risk factors associated with ARDS and ARDS progressing on Intubation or Death
Variables
|
ARDS (n = 65)
|
|
Intubation or Death (n = 30)
|
|
HR (95% CI)
|
P value
|
HR (95% CI)
|
P value
|
Clinical characteristics
|
|
|
|
|
Age
|
1.04 (1.01–1.06)
|
0.001
|
1.03 (1.01–1.06)
|
0.019
|
Age (≥ 65) years
|
2.24 (1.18–4.28)
|
0.014
|
3.07 (1.32–7.16)
|
0.009
|
Gender (male vs female)
|
2.08 (1.03–4.20)
|
0.040
|
0.70 (0.32–1.49)
|
0.352
|
Number of complaints (≥ 3)
|
1.50 (0.77–2.95)
|
0.236
|
4.74 (1.65–13.66)
|
0.004
|
Hypertension
|
1.03 (0.53–2.02)
|
0.928
|
1.61 (0.77–3.35)
|
0.204
|
Number of coexisting disorders (≥ 1)
|
1.15 (0.57–2.36)
|
0.693
|
1.82 (0.74–4.50)
|
0.192
|
Oxygenation Index
|
|
|
|
|
Values
|
NA
|
NA
|
0.99 (0.98-1.00)
|
0.001
|
< 200
|
NA
|
NA
|
3.05 (1.24–7.46)
|
0.015
|
< 150
|
NA
|
NA
|
3.00 (1.45–6.17)
|
0.003
|
< 100
|
NA
|
NA
|
2.54 (1.03–6.25)
|
0.042
|
Laboratory findings
|
|
|
|
|
Lymphocyte count /mm3 (< 1000)
|
4.72 (2.34–9.51)
|
< 0.001
|
1.58 (0.64–3.87)
|
0.319
|
Albumin, g/L (< 32)
|
3.36 (1.70–6.66)
|
0.001
|
0.88 (0.38–2.07)
|
0.775
|
Albumin/Globulin (< 1.5)
|
10.02 (3.08–32.60)
|
< 0.001
|
0.89 (0.34–2.34)
|
0.818
|
LDH, unit/L (> 280)
|
5.44 (2.78–10.64)
|
< 0.001
|
1.10 (2.51 − 0.35)
|
0.810
|
cTnI, ng/mL (> 0.04)
|
3.80 (1.91–7.55)
|
< 0.001
|
0.84 (0.36–1.95)
|
0.678
|
Glucose, mmol/L (> 7.1)
|
4.33 (2.27–8.25)
|
< 0.001
|
1.46 (0.64–2.92)
|
0.425
|
Creatinine, µmol/L (> 110)
|
3.88 (1.62–9.31)
|
0.002
|
0.54 (0.19–1.54)
|
0.247
|
GFR, ml/min/1.73m2 (< 80)
|
3.64 (1.91–6.93)
|
< 0.001
|
1.18 (0.58–2.43)
|
0.648
|
Sodium, mmol/L (< 135)
|
3.84 (1.90–7.75)
|
< 0.001
|
0.88 (0.38–2.05)
|
0.766
|
D-Dimer, mg/L (> 0.5)
|
3.99 (2.10–7.57)
|
< 0.001
|
0.81 (0.39–1.67)
|
0.569
|
PT, s (> 13.5)
|
5.55 (2.93–10.49)
|
< 0.001
|
0.69 (0.33–1.46)
|
0.337
|
INR (> 1.1)
|
10.02 (3.08–32.60)
|
< 0.001
|
1.18 (0.56–2.47)
|
0.659
|
ESR, mm/h (> 20)
|
6.80 (2.09–22.12)
|
0.001
|
1.33 (0.32–5.60)
|
0.696
|
C-Reactive Protein, mg/L (> 10)
|
7.47 (2.92–19.1)
|
< 0.001
|
0.71 (0.25–2.06)
|
0.533
|
Procalcitonin, µg/L (> 0.1)
|
4.39 (2.32–8.30)
|
< 0.001
|
0.74 (0.36–1.52)
|
0.418
|
* Data regarding the cTnI were missing for 2 ARDS patients who were dead. |
† Data regarding the Glucose were missing for 1 ARDS patient who were never intubation or not dead. |
‡ Data regarding the PTs were missing for 1 ARDS patient who were never intubated or not dead. |
§ Data regarding the ESR were missing for 6 ARDS patients who were never intubated or not dead. |
Abbreviations: HR; hazard ratio; WBC: White Blood Cell; TBIL: Total bilirubin, AST: aspartate transaminase, ALT: alanine aminotransaminase, LDH: lactate dehydrogenase, GFR: glomerular filtration rate, PT: prothrombin time, INR: international normalized ratio, ESR: Erythrocyte Sedimentation Rate. |