A total of 202 patients who underwent a first LT were included (Table 1), of which 118 (58.4%) were male, and the remaining 84 patients (41.6%) were female. The mean age was 54.19 ± 11.66. The predominant ethnicity was Caucasian (94.7% of patients). Eighty-six patients (28.6%) had diabetes mellitus. The main cause of end-stage liver disease was HCV infection, accounting for 125 cases (61.9%). Additionally, HCC in the setting of cirrhosis occurred in 115 patients (56.9%), being the main indication of LT in this cohort. The calculated median MELD score was 13 [IQR = 10–19].
Table 1
Demographic variables of 202 consecutive who underwent liver transplantation at a single center
| N (%) | Mean ± DP | Median + Iqr |
Age | | 54.19 +- 11.66 | 57 (Iqr 49.75–62) |
Male Gender | N = 118 (58.4%) | | |
Body Mass Index (BMI) | | 27.76 +- 5.457 | 27 (Iqr 24–31) |
MELD Score | | 16 +- 9 | 13 (Iqr 10–19) |
MELD-Na Score | | 16 +- 8 | 13 (Iqr 10–19) |
HCV infection | N = 125 (61,9%) | | |
Hepatocellular Carcinoma (HCC) | N = 115 (56,9%) | | |
Albumin | | 3.18 +- 0.73 | 3 (Iqr 3–3.5) |
Bilirubin | | 4.51 +- 8.4 | 1,70 (Iqr 0.9–3.22) |
INR | | 1. 77 +- 1,58 | 1,37 (Iqr 1.21 − 1.68) |
Sodium | | 139.66 +- 4.13 | |
Creatinine | | 1.04 +- 0.84 | 0,8 (Iqr 0.66–1.07) |
Diabetes | N = 86 (28.3%) | | |
Post-LT survival for the entire cohort of 202 patients as assessed by the Kaplan-Meier method at 1-, 3-, 5-, and 7 years was 81.6%, 73.1%, 67.6%, and 63%. There were 18 deaths during the first 30 days post-LT days (30-day mortality of 8.9%). Between the 31st and 180th days, there were 7 deaths. Between the 181st and 365th day post-LT, other 13 deaths occurred. Overall, a total of 38 deaths occurred during the first post-LT year for the 202 transplant patients, resulting in a one-year actual survival of 81.1%.
During the first 30 post-LT days, the main cause of death was graft dysfunction (n = 12) (either primary or secondary to vascular thrombosis or large-for-size grafts). Among the patients who died during the first 30 post-LT days, 3 suffered from hepatic artery thrombosis, 2 portal vein thrombosis, 4 hemorrhagic shocks. There were 3 abdominal compartment syndromes caused by large-for-size liver grafts. During this period, 5 of the 18 deaths (27.78%) were due to infections.
Between the 31st and 180th day post-LT, the main cause of death was infection (six of the seven deaths were caused by infection). Between days 181 and 365 post-LT, infection was also the main cause of death (eight of the thirteen deaths in this period were caused by infection).
Table 2a presents the results of univariate analysis by Cox regression with the outcome of mortality occurring throughout the study follow-up. According to this analysis, female donor gender (HR = 1.806, [95%CI = 1.091–2.988]; p = 0.021) was the only predictor of overall post-LT mortality.
Table 2
Univariate analysis of the factors to the outcome overall death (entire post-transplant follow-up) of 202 consecutive patients who underwent liver transplantation at a single center
| Hazard Ratio [IC 95%] | p-Value |
Age | 0.996[0.976–1.016] | 0.677 |
Female Gender | 0.830[0.511–1.348] | 0.451 |
Receptor Height | 1.002 [0.978–1.026] | 0.884 |
Receptor Weight | 1.006 [0.990–1.023] | 0.468 |
Body Mass Index (BMI) | 1.026[0.973–1.080] | 0.342 |
Diabetes | 1.367[0.836–2.237] | 0.213 |
MELD Score | 1.003[0.977–1.031] | 0.811 |
MELD-Na Socre | 1.003[0.977–1.030] | 0.840 |
HCV Infection | 0.912[0.563–1.477] | 0.708 |
Hepatocelular Carcinoma (HCC) | 1.003[0.623–1.614] | 0.991 |
Total Bilirubin | 1.011[0.986–1.037] | 0.389 |
INR | 0.886[0.702–1.118] | 0.309 |
Sodium | 1.008[0.951–1.068] | 0.788 |
Creatinine | 0.828[0.573–1.196] | 0.314 |
Platelets/20,000 | 1.022[0.960–1.088] | 0.501 |
Albumin | 0.749[0.546–1.027] | 0.072 |
Albumin–Bilirubina Grade (ALBI) 2 – categories grade 1/grade 2 ref (≤ -1.39) grade 3 (>-1.39) | 1.155[0.668–1.995] | 0.606 |
Pre-Transplant Dyalisis | 1.124[0.486–2.598] | 0.785 |
Infection Prior to LT | 1.301[0.744–2.275] | 0.355 |
Ascites Prior to LT | 1.405[0.876–2.253] | 0.158 |
Donor Infection | 0.956[0.550–1.644] | 0.875 |
Donor Age | 1.011[0.996–1.027] | 0.154 |
Donor Gender, Female | 1.806[1.091–2.988] | 0.021 |
Donor BMI | 0.988[0.914–1.069] | 0.771 |
Donor Height | 0.696 [0.037–13.192] | 0.809 |
Donor Weight | 0.996 [0.976–1.016] | 0.669 |
Height Difference between Donor and Recipient | 1.000[0.980–1.021] | 0.964 |
Weight Difference between Donor and Recipient | 0.996[0.982–1.010] | 0.545 |
Infection, Receptor During Transplant Hospitalization | 0.793[0.468–1.345] | 0.390 |
Infection During First 90 Post-Transplant Days | 0.646[0.403–1.035] | 0.069 |
Infection During First Year | 0.689[0.430–1.104] | 0.121 |
Anthropometric parameters of donor and recipient also were studied. The difference of donor and recipient weight was not related to a decreased post-LT survival (p = 0.545). Likewise, the difference of donor and recipient height was not related to a decreased post-LT survival (p = 0.964).
Figure 1a demonstrates the analysis of post-transplant survival using the Kaplan-Meier method, stratified by donor gender. Post-LT survival for patients who received a liver graft from a male donor method at 1, 3, 5, and 7 years was 86.3%, 79.1%, 73.8%, and 71 .8% versus 77.4%, 64.9%, 59.6%, 54.2% for patients who received liver from a female donor (p = 0.013).
Figure 1b depicts the analysis of post-transplant survival stratified by recipient gender. Post-LT survival for male recipients was not different from that of female recipients (p = 0.45).
Figure 2 shows recipient survival stratified in four groups by donor and recipient gender. The highest survival occurred for male patients receiving a liver from a male donor (1 year = 85.7%, 3 years = 80.1%, 5 years = 73.1% and 7 years = 73.1%), whereas the lowest survival occurred for male patients receiving a liver graft from female donors (1 year = 75%, 3 years = 68.5%, 5 years = 60.8% and 7 years = 52.6%) (p = 0.028). Analyzing only male gender recipients, receiving a liver from a female gender donor as compared with receiving a liver from a male donor was associated with an increase of 2.26 times in overall post-LT mortality (95%CI = 1.149–4.315, p = 0.018).
No statistically sigificant survival difference was detected for the comparisons between all the other donor-recipient gender comparisons [female donor to female recipient vs. male donor to male recipient, p = 0.213), (female donor to female recipient vs. female donor to male recipient, p = 0.466), (female donor to female recipient vs. male donor to female recipient, p = 0.513), (male donor to male recipient vs. male donor to female recipient, p = 0.689), (female donor to male recipient vs. male donor to female recipient, p = 0.12)].
Additional analyses were performed in the group that had the lowest overall survival (male recipients receiving livers from female donors). Among that subgroup of patients, the difference of donor and recipient weight was not related to a decreased post-LT survival (p = 0.425). Likewise, the difference between donor and recipient height was not related to a decreased post-LT survival (p = 0.114).
As an attempt to quantify the weight mismatches between donor and recipients, we calculated the difference between the weight of the donor and that of the recipient (donor weight – recipient). Thus, we have grouped the donor-to-recipient weight differences into three groups. First group included individuals with donor-recipient weight differences of more than 10 Kg (recipient weighted 10 or more kilos than the donor); for the second group donor-recipient weight difference was between − 10 and + 10 Kg; third group had a donor-recipient weight differences of more than 10 kg (recipient weighted 10 or less kilos than the donor). Post-LT survival for the three groups was not statistically different (p = 0.399).
In order to quantify the Height mismatches between donor and recipients, we calculated the difference between the height of the donor and that of the recipient (donor height – recipient). For quantifying the height differences between the donor and the recipient, we also grouped the height differences into three groups. The first group encompassed individuals with donor-recipient height differences of less than 10 cm (recipient was 10 or more centimeters taller than the donor); for the second group, donor- recipient height differences were between − 10 and + 10 cm; third group had patients with donor weight-recipient height differences 10 or more kilograms (recipient was 10 or more centimeters shorter than the donor). Post-LT survival for the three groups was not statistically different (p = 0.772).
Among the group of 46 male patients receiving livers from female donors, 12 deaths occurred during the first year (mortality rate of 26.1%) as compared to a 14% 1-year mortality of male recipients who received livers from male donors. Death causes of the 12 male recipients who received livers from female donors were: infection (n = 7, 58.3%), hemorrhagic shock (n = 1), hepatic artery thrombosis (n = 1), portal vein thrombosis (n = 1), unknown (n = 2). In contrast, in the group of male patients who received liver allografts from male donors, only 12.5% of the deaths occurring during the first post-LT year were caused by infection