Retrospective Cohort Study
Copyright ©The Author(s) 2024.
World J Gastrointest Surg. Feb 27, 2024; 16(2): 331-344
Published online Feb 27, 2024. doi: 10.4240/wjgs.v16.i2.331
Table 1 Donor and graft characteristics
Variable
Value (n = 656)
Male sex389 (59.3)
Blood type
    0238 (36.3)
    A267 (40.7)
    B111 (16.9)
    AB40 (6.1)
Pancreas offered (yes)145 (22.1)
Cardiac arrest (yes)93 (14.2)
Age (yr)60 (48-70)
BMI (kg/m²)26.3 (24.4-28.4)
ET-DRI1.72 (1.47-1.95)
Steatosis (%)2 (0-10)
Na (mEq/L)148 ± 9 (120-187)
ALT (U/L)54.3 ± 79.6 (5-898)
GGT (U/L)66.8 ± 99.8 (4-1129)
Bilirubin (mg/dL)14 ± 12.6 (1-146)
CRP (mg/L)162.6 ± 102.4 (1-621)
CIT (h)7.11 ± 2.3 (1.22-13.87)
Data are presented as mean ± SD with ranges (min-max) or median with IQR (interquartile ranges) when the distribution is skewed for continuous variables. Categorical variables are presented as counts (%). BMI: Body mass index; Na: Sodium; ALT: Alanine aminotransferase; GGT: Gamma-glutamyl transferase; CRP: C-reactive protein; ET-DRI: Eurotransplant Donor Risk Index; CIT: Cold ischemia time.
Table 2 Recipient characteristics
Variable
Value (n = 656)
Male sex469 (71.5)
Blood type
    0212 (32.3)
    A267 (40.7)
    B124 (18.9)
    AB53 (8.1)
Indication for LT
    Alcoholic liver cirrhosis197 (30.03)
    Cancer (HCC, CCC)184 (28.05)
    Cholestatic liver disease53 (8.08)
    Hepatitis C virus41 (6.25)
    Retransplantation83 (12.65)
    Miscellaneous98 (14.94)
Median (IQR)
Age (yr)59 (52-64)
BMI (kg/m²)26 (23.9-29.4)
Days on the waiting list25 (7-92)
Lab MELD16 (11-21)
BAR7 (4-10)
Data are presented as mean ± SD with ranges (min-max) or median with IQR (interquartile ranges) when the distribution is skewed for continuous variables. Categorical variables are presented as counts (%). BMI: Body mass index; LT: Liver transplantation; HCC: Hepatocellular carcinoma; CCC: Cholangiocarcinoma; BAR: Balance of risk; MELD: Model for End-Stage Liver Disease.
Table 3 Cox proportional hazards model – all variables and metrics
Variable
Coefficient (95%CI)
Hazard ratio (95%CI)
P value
Donor pre-procurement cardiac arrest (yes)0.400 (0.027, 0.774)1.493 (1.028, 2.168)
0.035
Recipient age0.031 (0.014, 0.049)1.032 (1.014, 1.050)< 0.001
Donor CRP0.001 (0.000, 0.003)1.001 (0.999, 1.003)0.055
BAR score0.031 (-0.001, 0.064)1.032 (0.999, 1.066)0.060
Indication for LT-cancer (HCC, CCC)0.137 (-0.275, 0.548)1.146 (0.760, 1.730)0.515
Indication for LT-hepatitis C virus1.029 (0.510, 1.548)2.798 (1.665, 4.702)< 0.001
Indication for LT-re-transplantation0.593 (0.098, 1.087)1.809 (1.103, 2.965)0.019
Indication for LT-miscellaneous0.307 (-0.190, 0.803)1.359 (0.827, 2.233)0.226
Indication for LT-cholestatic disease-0.371 (-1.168, 0.426)0.690 (0.311, 1.532)0.362
The model had no significant transformations and interactions, and the final model is the (linear) main effects model. Donor age was eliminated as insignificant in all previous steps of development. CRP: C-reactive protein; BAR: Balance of Risk; LT: Liver transplantation; HCC: Hepatocellular carcinoma; CCC: Cholangiocarcinoma.
Table 4 Cox proportional hazards model – excluded metrics (Model for End-Stage Liver Disease, Balance of Risk, and Eurotransplant Donor Risk Index score)
Variable
Coefficient (95%CI)
Hazard ratio (95%CI)
P value
Donor pre-procurement cardiac arrest (yes)0.401 (0.029, 0.774)1.494 (1.029, 2.168)
0.035
Recipient age0.034 (0.016, 0.051)1.034 (1.016, 1.053)< 0.001
Donor CRP0.001 (0.000, 0.003)1.001 (0.999, 1.003)0.060
Indication for LT-cancer (HCC, CCC)0.062 (-0.342, 0.465)1.064 (0.711, 1.592)0.764
indication for LT-hepatitis C virus1.033 (0.515, 1.552)2.811 (1.673, 4.722)< 0.001
Indication for LT-re-transplantation0.806 (0.367, 1.245)2.240 (1.444, 3.474)< 0.001
Indication for LT-miscellaneous0.353 (-0.140, 0.845)1.423 (0.870, 2.328)0.160
Indication for LT-cholestatic disease-0.346 (-1.144, 0.451)0.707 (0.319, 1.570)0.395
The final model did not include any transformations and interactions, as they were insignificant, and the final model is the (linear) main effects model. CRP: C-reactive protein; LT: Liver transplantation; HCC: Hepatocellular carcinoma; CCC: Cholangiocarcinoma.
Table 5 Cox proportional hazards model – all variables; excluded retransplanted patients
Variable
Coefficient (95%CI)
Hazard ratio (95%CI)
P value
Donor pre-procurement cardiac arrest (yes)0.393 (-0.0281, 0.813)1.481 (0.972, 2.255)0.067
Recipient age0.001 (-0.039, 0.040)1.001 (0.961, 1.041)0.98
Donor CRP0.002 (0.001, 0.004)1.002 (1.001, 1.004)0.006
Lab MELD0.027 (-0.034, 0.088)1.028 (0.967, 1.092)0.380
BAR score0.024 (-0.056, 0.104)1.024 (0.946, 1.109)0.557
Indication for LT-cancer (HCC, CCC)-2.867 (-6.365, 0.631)0.057 (0.002, 1.878)0.108
Indication for LT-hepatitis C virus-4.492 (-9.517, 0.532)0.011 (0.000, 1.703)0.080
Indication for LT-miscellaneous-0.917 (-4.091, 2.257)0.400 (0.017, 9.555)0.571
indication for LT-cholestatic disease0.325 (-3.841, 4.490)1.384 (0.021, 9.146)0.879
Lab MELD × cancer (HCC, CCC)0.026 (-0.030, 0.083)1.027 (0.970, 1.086)0.363
Lab MELD × hepatitis C virus-0.023 (-0.089, 0.044)0.978 (0.915, 1.044)0.500
Lab MELD × indication miscellaneous-0.034 (-0.091, 0.024)0.967 (0.913, 1.024)0.253
Lab MELD × cholestatic disease-0.177 (-0.331, -0.024)0.838 (0.718, 0.977)0.023
Recipient age × cancer (HCC, CCC)0.047 (-0.009, 0.102)1.048 (0.991, 1.107)0.098
Recipient age × hepatitis C virus0.103 (0.021, 0.186)1.109 (1.022, 1.204)0.013
Recipient age × indication miscellaneous0.032 (-0.020, 0.083)1.033 (0.980, 1.088)0.228
Recipient age × cholestatic disease0.038 (-0.036, 0.112)1.039 (0.965, 1.118)0.309
The final model did not include any transformations as they were insignificant, and the final model is the (linear) main effects model. Significant interactions between variables are presented. MELD Model for End-Stage liver disease; BAR: Balance of Risk; CRP: C-reactive protein; LT: Liver transplantation; HCC: Hepatocellular carcinoma; CCC: Cholangiocarcinoma.
Table 6 Cox proportional hazards model-excluded metrics (Model for End-Stage Liver Disease, Balance of Risk, and Eurotransplant Donor Risk Index score) and retransplanted patients
Variable
Coefficient (95%CI)
Hazard ratio (95%CI)
P value
Donor pre-procurement cardiac arrest (yes)0.406 (-0.006, 0.817)1.500 (0.994, 2.264)
0.053
Recipient age0.035 (0.016, 0.055)1.035 (1.016, 1.004)< 0.001
Donor CRP0.002 (0.000, 0.004)1.002 (1.000, 1.004)0.015
Indication for LT-cancer (HCC, CCC)0.064 (-0.341, 0.469)1.066 (0.711, 1.599)0.757
Indication for LT-hepatitis C virus1.058 (0.538, 1.578)2.881 (1.712, 4.846)< 0.001
Indication for LT-miscellaneous0.365 (-0.128, 0.859)1.442 (0.880, 2.361)0.146
Indication for LT-cholestatic disease-0.328 (-1.126, 0.470)0.720 (0.324, 1.600)0.420
The final model did not include any transformations and interactions, as they were insignificant, and the final model is the (linear) main effects model. CRP: C-reactive protein; LT: Liver transplantation; HCC: Hepatocellular carcinoma; CCC: Cholangiocarcinoma.
Table 7 Donor characteristics and comparison of the older and younger group
Older (n = 87)
Younger (n = 124)
P value
Test
Gender< 0.01χ2 test
    Male44 (50.57)88 (70.97)
    Female43 (49.43)36 (29.03)
Steatosis0.4χ2 test
    Negligible70 (81.40)96 (78.69)
    Mild12 (13.95)13 (10.66)
    Moderate4 (4.65)12 (9.84)
    Severe0 (0)1 (0.82)
Cardiac arrest0.01χ2 test
    No81 (93.1)99 (79.8)
    Yes6 (6.9)25 (20.2)
Age77 (76-80)32 (23-40)< 0.01Mann-Whitney
BMI (kg/m²)27.55 (25.23-29.4)24.69 (22.75-26.31)< 0.01Mann-Whitney
ET-DRI2.02 (1.85-2.05)1.28 (1.15-1.46)< 0.01Mann-Whitney
Sodium(mEq/L)147 ± 7.6 (133-165)146 ± 8.9 (120-169)0.51t-test
ALT (U/L) 33.8 ± 51.3 (5-385)93.9 ± 130.3 (8-898)< 0.01t-test
GGT (U/L)48.5 ± 76.1 (4-581)90.1 ± 163.1 (6-1129)0.03t-test
Bilirubin(mg/dL)15.4 ± 10.9 (3-71)13.6 ± 16.4 (1-146)0.38t-test
CRP (mg/L)175.8 ± 104.7 (1-440)157.6 ± 94.1 (1-360)0.2t-test
CIT (h)6.44 ± 2.1 (2.17-11.45)7.73 ± 2.7 (1.93-13.87)< 0.01t-test
Data are presented as mean ± SD with ranges (min-max) or median with IQR (interquartile ranges) when the distribution is skewed for continuous variables. Categorical variables are presented as counts (percentages). BMI: Body mass index; Na: Sodium; ALT: Alanine aminotransferase; GGT: Gamma-glutamyl transferase; CRP: C-reactive protein; ET-DRI: Eurotransplant donor risk index; CIT: Cold ischemia time.
Table 8 Recipient characteristics and comparison of the older and younger group
Older (n = 87)
Younger (n = 124)
P value
Test
Gender0.03χ2 test
    Male70 (80.46)82 (66.13)
    Female17 (19.54)42 (33.87)
Indication for LT0.4χ2 test
    Alcoholic cirrhosis38 (43.68)32 (25.81)
    Cancer (HCC, CCC)33 (37.94)29 (23.39)
    Viral hepatitis6 (6.9)18 (14.52)
    Miscellaneous10 (11.5)45 (36.32)
Urgency
    Elective87 (100)118 (95.16)0.04Fischer's exact test
    High0 (0)6 (4.84)
Stay in ICU0.57χ2 test
    No65 (74.71)98 (79.03)
    Yes22 (25.29)26 (20.97)
Age60 (55-66)58 (50-63)< 0.01Mann-Whitney
BMI (kg/m²)27.92 (24.61-29.91)25.25 (23.45-27.3)< 0.01Mann-Whitney
MELD15 (11-18)16 (11-21)0.13Mann-Whitney
BAR5 (4-9)6 (2-9)0.45Mann-Whitney
Data are presented as mean ± SD with ranges (min-max) or median with IQR (interquartile ranges) when the distribution is skewed for continuous variables. Categorical variables are presented as counts (percentages). BMI: Body mass index; LT: Liver transplantation; HCC: Hepatocellular carcinoma; CCC: Cholangiocarcinoma; ICU: Intensive care unit; MELD: Model for End-Stage Liver Disease; BAR: Balance of risk.