Baseline characteristics
A total of 603 consecutive patients with acute variceal bleeding (AVB) were screened, and 186 patients were excluded for the following reasons: without cirrhosis (n =46), without ICU stays (n =129) and incomplete records (n =11). Finally, 417 patients with cirrhosis and AVB who met the inclusion and exclusion criteria were included in this study. Their baseline characteristics were shown in Table 1. Patients were predominantly male 297 (71.2%), with a median age of 57 years. Patients were predominantly white 277 (66.4%). The main etiology of cirrhosis was alcohol (56.8%). With regard to the complications of cirrhosis, a total of 244 (58.5%), 247 (59.3%), 109 (26.1%) and 49 (11.7%) patients had ascites, hepatic encephalopathy (HE), bacterial infection and portal vein thrombosis (PVT) at admission, respectively. 52 (12.4%) patients had concurrent hepatocellular carcinoma (HCC). Of all the patients included, 218 (52.2%) had EASL-ACLF at baseline (40 [18.3%], 70 [32.2%] and 108 [49.5%] had ACLF grade 1, grade 2 and grade 3, respectively). Age, gender, race and etiology were similar between patients with and without ACLF. As expected, patients with ACLF more frequently presented with ascites, bacterial infections and hepatic encephalopathy, as well as significantly higher heart rate, peripheral white blood cell (WBC) count, serum total bilirubin, alanine aminotransferase (ALT), aspartate aminotransferase (AST), international normalized ratio (INR), prothrombin time (PT), serum creatinine, blood urea nitrogen, serum potassium, glucose and lower mean arterial pressure, SPO2 (percutaneous oxygen saturation)/ FIO2 (fraction of inspired oxygen), hemoglobin, albumin and serum sodium at baseline. In addition, the ACLF patients significantly presented higher prognosis scores (CTP, MELD, MELD-Na) and proportion of CTP class C than mere AD patients (P <0.001). There were no significant differences of the incidence of comorbidities between ACLF and mere AD patients, except renal disease (P =0.005). Besides, the length of ICU stay and hospital stay in ACLF patients were significantly higher than that in mere AD patients.
Table 1 Baseline characteristics of all patients and patients with or without ACLF (N = 417)
Baseline characteristics
|
All patients (n= 417)
|
No ACLF (n= 199)
|
ACLF (n= 218)
|
P value
|
Gender n (%)
|
|
|
|
0.305
|
Male
|
297 (71.2)
|
137 (68.8)
|
160 (73.4)
|
|
Female
|
120 (28.8)
|
62 (31.2)
|
58 (26.6)
|
|
Age
|
57 (49-63)
|
58 (50-63)
|
56 (49-63)
|
0.406
|
Race n (%)
|
|
|
|
0.209
|
WHITE
|
277 (66.4)
|
140 (70.4)
|
137 (62.8)
|
|
BLACK
|
48 (11.5)
|
16(8.0)
|
32 (14.7)
|
|
HISPANIC/LATINO
|
45 (10.8)
|
23 (11.6)
|
22 (10.1)
|
|
ASIAN
|
19 (4.6)
|
9 (4.5)
|
10 (4.6)
|
|
OTHERS
|
28 (6.7)
|
11 (5.5)
|
17 (7.8)
|
|
Etiology of cirrhosis n (%)
|
|
|
|
0.279
|
Alcohol
|
237 (56.8)
|
104 (52.3)
|
133 (61.0)
|
|
Virus
|
29 (7.0)
|
17 (8.5)
|
12 (5.5)
|
|
Alcohol+Virus
|
18 (4.3)
|
10 (5.0)
|
8 (3.7)
|
|
Others
|
133 (31.9)
|
68 (34.2)
|
65 (29.8)
|
|
Concurrent HCC n (%)
|
52 (12.5)
|
31 (15.6)
|
21 (9.6)
|
0.066
|
Comorbidities
|
|
|
|
|
Miocardial infarction
|
18 (4.3)
|
6 (3.0)
|
12 (5.5)
|
0.212
|
Congestive heart failure
|
32 (7.7)
|
14 (7.0)
|
18 (8.3)
|
0.640
|
Cerebrovascular disease
|
15 (3.6)
|
6 (3.0)
|
9 (4.1)
|
0.542
|
Chronic pulmonary disease
|
64 (15.3)
|
31 (15.6)
|
33 (15.1)
|
0.901
|
Diabetes
|
29 (7.0)
|
13 (6.5)
|
16 (7.3)
|
0.746
|
Peripheral vascular disease
|
13 (3.1)
|
7 (3.5)
|
6 (2.8)
|
0.653
|
Renal disease
|
48 (11.5)
|
14 (7.0)
|
34 (15.6)
|
0.006
|
Decompensation at admission
|
|
|
|
|
Ascites n (%)
|
244 (58.5)
|
82 (41.2)
|
162 (74.3)
|
<0.001
|
HE n (%)
|
247 (59.3)
|
77 (38.7)
|
170 (78.0)
|
<0.001
|
Ⅰ+Ⅱ
|
131 (31.5)
|
56 (28.1)
|
75 (34.4)
|
|
Ⅲ+Ⅳ
|
116 (27.8)
|
21 (10.6)
|
95 (43.6)
|
|
Bacterial infection
|
109 (26.1)
|
29 (14.6)
|
80 (36.7)
|
<0.001
|
Pneumonia
|
39 (9.3)
|
13 (6.5)
|
26 (11.9)
|
|
Urinary tract infection
|
38 (9.1)
|
10 (5.0)
|
28 (12.8)
|
|
Spontaneous bacterial peritonitis
|
32 (7.6)
|
7 (3.5)
|
25 (11.5)
|
|
Others
|
16 (3.8)
|
5 (2.5)
|
11 (5.0)
|
|
PVT
|
49 (11.8)
|
26 (13.1)
|
23 (10.6)
|
0.426
|
Vital signs
|
|
|
|
|
Mean arterial pressure (mmHg)
|
75 (69-82)
|
79 (71-86)
|
72 (67-78)
|
<0.001
|
Heart rate (bpm)
|
86 (75-98)
|
85 (73-98)
|
87 (76-98)
|
0.005
|
SPO2/FIO2
|
405 (150-443)
|
433 (192-448)
|
229 (104-438)
|
<0.001
|
Laboratory tests
|
|
|
|
|
White blood cell (109/L)
|
10.6 (6.8-16.1)
|
7.7 (5.6-11.3)
|
13.9 (9.6-20.0)
|
<0.001
|
Hemoglobin (mg/dl)
|
8.3±1.9
|
8.6±1.8
|
8.0±1.9
|
0.001
|
Platelet (109/L)
|
71.0 (48.0-108.0)
|
72.0 (50.5-113.0)
|
68.5 (45.0-106.8)
|
0.079
|
Total bilirubin (mg/dL)
|
3.2 (1.6-7.3)
|
2.0 (1.2-4.0)
|
5.2 (2.4-13.2)
|
<0.001
|
Albumin, g/dL
|
2.9±0.6
|
3.0 (2.6-3.4)
|
2.8±0.7
|
<0.001
|
ALT (U/L)
|
39 (24-65)
|
35 (24-52)
|
42 (24-100)
|
0.005
|
AST (U/L)
|
76 (46-155)
|
64 (43-112)
|
93 (53-262)
|
<0.001
|
INR
|
1.8 (1.5-2.2)
|
1.6 (1.4-1.8)
|
2.1 (1.7-2.7)
|
<0.001
|
Prothrombin time (s)
|
19.2 (16.0-23.8)
|
17.1 (15.2-19.7)
|
22.7 (18.4-29.6)
|
<0.001
|
Serum creatinine, mg/dL
|
1.1 (0.8-1.9)
|
0.8 (0.7-1.0)
|
1.8 (1.1-2.8)
|
<0.001
|
Blood urea nitrogen (mg/dl)
|
29.0 (18.0-45.0)
|
22.0 (15.0-34.0)
|
37.0 (23.0-57.0)
|
<0.001
|
Serum sodium, mEq/L
|
137.0 (133.0-140.0)
|
138.0 (135.0-141.0)
|
136.0 (131.0-140.0)
|
0.001
|
Serum potassium, mEq/L
|
4.5 (4.1-5.4)
|
4.4 (4.0-4.9)
|
4.8 (4.2-5.7)
|
<0.001
|
Glucose (mg/dl)
|
149.0 (121.0-198.5)
|
137.0 (118.0-187.5)
|
163.0 (133.3-201.0)
|
<0.001
|
Organ failures n (%)
|
|
|
|
|
Circulatory failure
|
116 (27.8)
|
9 (4.5)
|
107 (49.1)
|
<0.001
|
Respiratory failure
|
131 (31.4)
|
7 (3.5)
|
124 (56.9)
|
<0.001
|
Cerebral failure
|
116 (27.8)
|
21 (10.6)
|
95 (43.6)
|
<0.001
|
Renal failure
|
87 (20.8)
|
0 (0)
|
120 (55.0)
|
<0.001
|
Coagulation failure
|
77 (18.4)
|
3 (1.5)
|
74 (33.9)
|
<0.001
|
Liver failure
|
62 (14.8)
|
4 (2.0)
|
58 (26.6)
|
<0.001
|
Specific treatments n (%)
|
|
|
|
|
Vasopressors
|
140 (33.5)
|
14 (7.0)
|
126 (57.8)
|
<0.001
|
Mechanical ventilation
|
131 (31.4)
|
7 (3.5)
|
124 (56.9)
|
<0.001
|
Renal replacement therapy
|
33 (7.9)
|
0 (0)
|
33 (15.1)
|
<0.001
|
Prognosis scores at enrollment
|
|
|
|
|
CTP
|
11 ( 8-12)
|
9 (7-11)
|
12 (10-13)
|
<0.001
|
MELD
|
19 ( 14-28)
|
14 (12-18)
|
28 (21-34)
|
<0.001
|
MELD-Na
|
22 ( 14-33)
|
15 (12-21)
|
31 (22-40)
|
<0.001
|
CTP class (A/B/C) n (%)
|
31 (7.4%)/123 (29.4%)/263 (63.2%)
|
30 (15.0%)/95 (47.7%)/74 (37.3%)
|
1 (0.4%)/28 (12.8%)/189 (86.8%)
|
<0.001
|
Length of ICU stay (days)
|
2 (1-4)
|
2 (1-2)
|
4 (2-6)
|
<0.001
|
Length of hospital stay (days)
|
7 (4-14)
|
5 (3-8)
|
12 (5-20)
|
<0.001
|
6-week mortality rate n (%)
|
124 (29.7)
|
22 (11.1)
|
102 (46.8)
|
<0.001
|
Abbreviations: ACLF, acute-on-chronic liver failure; HCC, hepatocellular carcinoma; HE, hepatic encephalopathy; SPO2, percutaneous oxygen saturation; FIO2, fraction of inspired oxygen; PVT, portal vein thrombosis; ALT, alanine aminotransferase; AST, aspartate aminotransferase; INR, international normalized ratio; CTP, Child-Turcotte-Pugh; MELD, model for end-stage liver disease; MELD-Na, MELD-sodium.
NOTE: data were described as means (±standard deviation), medians (interquartile range) or numbers (percentage) where appropriate and compared with independent sample t-test, Mann-Whitney U test and Chi square test accordingly.
Cumulative survival rates of cirrhotic patients hospitalized with acute variceal bleeding
Among all enrolled 417 patients, 124 patients were dead during a 42-day follow-up period and the cumulative survival rates at 42-days were 70.3%. A total of 102 patients with ACLF and 22 patients without ACLF were dead during follow-up, respectively. The cumulative 42-day survival rates in patients with ACLF was significantly lower than in those without ACLF (53.2% vs. 88.9%, P <0.001) (Fig. 2A). Furthermore, the cumulative 42-day survival rates decreased gradually as the grade of ACLF increased (P <0.001) (Fig. 2B) . A total of 9 (22.5%), 24 (34.2%) and 69 (63.8%) patients were dead among patients with ACLF grade I, II, and III during follow-up, respectively, (Fig. 2B).
ACLF as an independent risk factor of 6-week mortality in cirrhotic patients with AVB
To further validate the role of ACLF in the prognosis of cirrhotic patients hospitalized with AVB, we performed Cox-proportional hazards regression analysis based on the presence of ACLF or not at admission and the well recognized risk factors for the prognosis of cirrhotic patients with AVB. In the univariable analysis, the variables found to be statistically significant included race, mean arterial pressure (MAP), SPO2 (percutaneous oxygen saturation) / FIO2 (fraction of inspired oxygen), presence of ACLF at admission, concomitant of miocardial infarction and renal disease, hepatocellular carcinoma (HCC), ascites, hepatic encephalopathy (HE), white blood cell (WBC), hemoglobin (HGB), albumin (ALB), total bilirubin (TB), prothrombin time (PT), international normalized ratio (INR), alanine aminotransferase (ALT); aspartate aminotransferase (AST), serum sodium, serum potassium, serum creatinine (Scr), blood urea nitrogen (BUN) and the well established prognosis scores (Table 2). As INR and PT are both the biochemistry markers reflecting coagulation function, Scr and BUN reflecting renal function, we only select INR and Scr for further multivariable analysis. Multivariable analysis showed that only ACLF (HR, 2.74, 95% CI: 1.54-4.88, P <0.001), HCC (HR, 2.69, 95% CI: 1.64-4.43, P <0.001), MAP (HR, 0.96, 95% CI: 0.93-0.98, P <0.001), WBC (HR, 1.02, 95% CI: 1.00-1.04, P= 0.023), TB (HR, 1.03, 95% CI: 1.01-1.05, P <0.001), ALB (HR, 0.55, 95% CI: 0.40-0.76, P <0.001) and INR (HR, 1.24, 95% CI: 1.10-1.39, P <0.001) remained in the final regression model (Fig. 2).
Table 2 Risk factors for 6-week mortality in all the cirrhotic patients hospitalized with AVB (N = 417)
Variable
|
univariable analysis
HR (95% CI) P value
|
multivariable analysis
HR (95% CI) P value
|
Gender
|
|
|
Female
|
0.67 (0.44-1.01) 0.057
|
0.73 (0.47-1.15) 0.179
|
Age
|
1.01 (0.99-1.02) 0.426
|
|
Race
|
|
|
Non white
|
1.63 (1.14-2.33) 0.007
|
1.11 (0.74-1.66) 0.614
|
Etiology of cirrhosis
|
|
|
Non alcohol
|
0.97 (0.68-1.38) 0.845
|
|
Concurrent HCC
|
1.66 (1.05-2.63) 0.031
|
2.69 (1.64-4.43) <0.001
|
Infection
|
1.32 (0.91-1.93) 0.149
|
|
Ascites
|
1.99 (1.39-2.95) 0.001
|
0.99 (0.64-1.55) 0.981
|
Hepatic encephalopathy
|
1.37 (1.10-1.71) 0.005
|
0.81 (0.62-1.06) 0.124
|
PVT
|
1.55 (0.97-2.48) 0.068
|
|
Mean arterial pressure
|
0.94 (0.92-0.96) <0.001
|
0.96 (0.93-0.98) <0.001
|
SPO2/FIO2
|
1.00 (1.00-1.00) 0.001
|
1.00 (1.00-1.00) 0.641
|
White blood cell
|
1.04 (1.03-1.05) <0.001
|
1.02 (1.00-1.04) 0.023
|
Hemoglobin
|
0.82 (0.74-0.91) <0.001
|
0.91 (0.82-1.01) 0.063
|
Platelet
|
1.00 (0.99-1.00) 0.230
|
|
Total bilirubin
|
1.04 (1.03-1.05) <0.001
|
1.03 (1.01-1.05) <0.001
|
Albumin
|
0.39 (0.29-0.54) <0.001
|
0.55 (0.40-0.76) <0.001
|
ALT
|
1.00 (1.00-1.00) 0.002
|
1.00 (1.00-1.00) 0.387
|
AST
|
1.00 (1.00-1.00) 0.009
|
|
INR
|
1.43 (1.33-1.53) <0.001
|
1.24 (1.10-1.39) <0.001
|
Prothrombin time
|
1.02 (1.02-1.03) <0.001
|
|
Serum creatinine
|
1.19 (1.13-1.26) <0.001
|
1.00 (0.90-1.10) 0.923
|
Blood urea nitrogen
|
1.01 (1.00-1.01) 0.001
|
|
Serum sodium
|
0.97 (0.94-0.99) 0.016
|
1.02 (0.99-1.05) 0.185
|
Serum potassium
|
1.46 (1.23-1.72) <0.001
|
1.16 (0.95-1.41) 0.157
|
Glucose
|
1.00 (1.00-1.00) 0.229
|
|
ACLF
|
5.52 (3.48-8.76) <0.001
|
2.74 (1.54-4.88) <0.001
|
Concomitant disease
|
|
|
Miocardial infarction
|
2.48 (1.31-4.74) 0.006
|
1.22 (0.56-2.67) 0.62
|
Congestive heart failure
|
1.04 (0.54-1.98) 0.909
|
|
Cerebrovascular disease
|
1.62 (0.76-3.48) 0.213
|
|
Chronic pulmonary disease
|
0.88 (0.54-1.46) 0.625
|
|
Diabetes
|
1.50 (0.83-2.72) 0.181
|
|
Peripheral vascular disease
|
1.78 (0.78-4.04) 0.169
|
|
Renal disease
|
1.74 (1.09-2.79) 0.020
|
1.21 (0.73-2.01) 0.464
|
Prognosis scores
|
|
|
CTP
|
1.38 (1.17-1.62) <0.001
|
|
MELD
|
1.10 (1.08-1.12) <0.001
|
|
MELD-Na
|
1.06 (1.05-1.08) <0.001
|
|
Abbreviations: ACLF, acute-on-chronic liver failure; SPO2, percutaneous oxygen saturation; FIO2, fraction of inspired oxygen; HCC, hepatocellular carcinoma; PVT, portal vein thrombosis; ALT, alanine aminotransferase; AST, aspartate aminotransferase; INR, international normalized ratio; CTP, Child-Turcotte-Pugh; MELD, model for end-stage liver disease. MELD-Na, MELD-sodium.
Prediction performance of prognosis scores
1 Discrimination performance
To validate the discrimination performance of the common prognosis scores for the 6-week mortality in cirrhotic patients hospitalized with AVB, we performed ROC on them in ACLF (Fig. 3A) and AD patients (Fig. 3B), respectively. In the ACLF patients, the AUROC calculated for CTP, MELD, MELD-Na were 0.658 (95% CI, 0.591–0.721), 0.728 (95% CI, 0.664–0.786), 0.725 (95% CI, 0.660–0.783) and 0.729 (95% CI, 0.665–0.787), respectively (Table 3). In the Delong test, there were no significant difference among the AUROC for these prognosis scores (P >0.05). The cutoff value, sensitivity and specificity for above mentioned prognosis scores were 11/73.5/53.5, 25/80.4/58.8, 26/88.2/52.6 and 61/67.7/73.3, respectively (Table 3). In the AD patients, the AUROC calculated for CTP, MELD, MELD-Na and CLIF-C AD were 0.686 (95% CI, 0.617–0.750), 0.674 (95% CI, 0.605–0.739), 0.667 (95% CI, 0.597–0.732) and 0.737 (95% CI, 0.670–0.797), respectively (Table 3). In the Delong test, there were no significant difference among the AUROC for these prognosis scores (P >0.05). The cutoff value, sensitivity and specificity for above mentioned prognosis scores were 10/54.6/77.4, 14/72.7/55.4, 23/40.9/88.1 and 55/77.3/68.4, respectively (Table 3).
To validate the calibration performance of the common prognosis scores for the 6-week mortality in cirrhotic patients hospitalized with AVB, we performed Hosmer-Lemeshow goodness-of-fit test for these prognosis scores (Table 3). In the ACLF patients, the P value between observed and predicted probability of 6-week mortality for CTP, MELD, MELD-Na and CLIF-C ACLF were 0.024, 0.650, 0.004 and 0.491, respectively. In the AD patients, the P value between observed and predicted probability of 6-week mortality for CTP, MELD, MELD-Na and CLIF-C ADs were 0.836, 0.670, 0.554 and 0.526, respectively.
To overcome the shortcomings of Hosmer-Lemeshow goodness-of-fit test in the evaluation of calibration, we plotted the calibration curves for the prognostic scores (Fig. 4). In ACLF patients, the visually inspected concordance between observed and predicted probability of 6-week mortality for CLIF-C ACLF were excellent and superior to those for the other prognosis scores (Fig. 4A). In AD patients, the visually inspected concordance between observed and predicted probability of 6-week mortality for MELD, MELD-Na and CLIF-C ADs were satisfactory and superior to that for CTP (Fig. 4B).
3 Overall performance
To validate the overall performance of the common prognosis scores for the 6-week mortality in cirrhotic patients hospitalized with AVB, we calculated the Brier score and R2 value for these prognosis scores (Table 3). In the ACLF patients, the Brier score and R2 value for CTP, MELD, MELD-Na and CLIF-C ACLF were 0.229/0.104, 0.210/0.203, 0.213/0.187 and 0.209/0.219, respectively. In the AD patients, the Brier score and R2 value for CTP, MELD, MELD-Na and CLIF-C ADs were 0.094/0.077, 0.094/0.068, 0.093/0.073 and 0.087/0.173, respectively.
Table 3 Predictive values of prognostic scores
Scores
|
AUC
|
Youden index
|
Cutoff value
|
SEN
|
SPE
|
PPV
|
NPV
|
Brier
|
R2
|
P in H-L test
|
ACLF patients
|
|
|
|
|
|
|
|
|
|
|
CTP
|
0.658
|
0.27
|
11
|
73.5
|
53.5
|
58.1
|
69.7
|
0.229
|
0.104
|
0.024
|
MELD
|
0.728
|
0.39
|
25
|
80.4
|
58.8
|
63.1
|
77.3
|
0.210
|
0.203
|
0.650
|
MELD-Na
|
0.725
|
0.41
|
26
|
88.2
|
52.6
|
62.1
|
83.6
|
0.213
|
0.187
|
0.004
|
CLIF-C ACLF
|
0.729
|
0.41
|
61
|
67.7
|
73.3
|
69.0
|
72.0
|
0.209
|
0.219
|
0.491
|
AD patients
|
|
|
|
|
|
|
|
|
|
|
CTP
|
0.686
|
0.32
|
10
|
54.6
|
77.4
|
23.1
|
93.2
|
0.094
|
0.077
|
0.836
|
MELD
|
0.674
|
0.28
|
14
|
72.7
|
55.4
|
16.8
|
94.2
|
0.094
|
0.068
|
0.670
|
MELD-Na
|
0.667
|
0.29
|
23
|
40.9
|
88.1
|
30.0
|
92.3
|
0.093
|
0.073
|
0.554
|
CLIF-C AD
|
0.737
|
0.46
|
55
|
77.3
|
68.4
|
23.3
|
96.0
|
0.087
|
0.149
|
0.526
|
Abbreviations: AUC, area under receiver operating characteristic curve; SEN, sensitivity; SPE, specificity; PPV, positive predictive value; NPV, negative predictive value; H-L test, Hosmer-Lemeshow goodness-of-fit test. CLIF-C ACLF, Chronic liver failure-organ failure-Consortium acute-on-chronic liver failure; CLIF-C AD, Chronic liver failure-organ failure-Consortium Acute Decompensation.