Transplantation With Livers From Deceased Donors Older Than 75 Years. Transplantation. 2015;99:2534-2542. [PMID: 25909464 DOI: 10.1097/tp.0000000000000728]

Older liver grafts from donation after circulatory death are associated with impaired survival and higher incidence of biliary non-anastomotic stricture

BACKGROUND

Grafts from older donors after circulatory death were associated with inferior outcome in liver transplants in the past. But it has seemed to remain controversial in the last decade, as a result of modified clinical protocols, selected recipients, and advanced technology of organ perfusion and preservation. The present study aimed to examine the impact of older donor age on complications and survival of liver transplant using grafts from donation after circulatory death (DCD).

METHODS

A total of 944 patients who received DCD liver transplantation from 2015 to 2020 were included and divided into two groups: using graft from older donor (aged ≥ 65 years, n = 87) and younger donor (age < 65 years, n = 857). Propensity score matching (PSM) was applied to eliminate selection bias.

RESULTS

A progressively increased proportion of liver transplants with grafts from older donors was observed from 1.68% to 15.44% during the study period. The well-balanced older donor (n = 79) and younger donor (n = 79) were 1:1 matched. There were significantly more episodes of biliary non-anastomotic stricture (NAS) in the older donor group than the younger donor group [15/79 (19.0%) vs. 6/79 (7.6%); P = 0.017]. The difference did not reach statistical significance regarding early allograft dysfunction (EAD) and primary non-function (PNF). Older livers had a trend toward inferior 1-, 2-, 3-year graft and overall survival compared with younger livers, but these differences were not statistically significant (63.1%, 57.6%, 57.6% vs. 76.9%, 70.2%, 67.7%, P = 0.112; 64.4%, 58.6%, 58.6% vs. 76.9%, 72.2%, 72.2%, P = 0.064). The only risk factor for poor survival was ABO incompatible transplant (P = 0.008) in the older donor group. In the subgroup of ABO incompatible cases, it demonstrated a significant difference in the rate of NAS between the older donor group and the younger donor group [6/8 (75.0%) vs. 3/14 (21.4%); P = 0.014].

CONCLUSIONS

Transplants with grafts from older donors (aged ≥ 65 years) after circulatory death are more frequently associated with inferior outcome compared to those from younger donors. Older grafts from DCD are more likely to develop NAS, especially in ABO incompatible cases.

End-ischemic hypothermic oxygenated machine perfusion does not improve renal outcome following liver transplantation from aged donors: A single-center retrospective report

BACKGROUND

Organ transplantation using grafts from elderly donors entails a higher risk for severe ischemia-reperfusion injury (IRI). Advanced IRI after liver transplantation (LT) seems to be associated with the development of acute kidney injury (AKI). We studied if end-ischemic hypothermic oxygenated machine perfusion (HOPE) of liver grafts, aimed at mitigating liver IRI, impacts on the frequency and severity of AKI after LT.

METHODS

LTs performed at our center between January 2017 and December 2022 using organs from deceased brain-dead donors aged 70 or older were reviewed. From November 2020 on, HOPE was performed routinely in this donor category. The frequency and severity of AKI (KDIGO criteria) within 48 hours of graft reperfusion and the model of early allograft function (MEAF) were compared between HOPE-LTs (n = 30) and control LTs (n = 71).

RESULTS

AKI developed in 23/30 (77%) HOPE-LTs and in 40/71 (56%) control LTs (p = n.s.), with no difference in severity and timing between groups. Renal replacement therapy was required in 3/30 (10%) HOPE-LTs and 6/71 (8%) control LTs. In addition, transaminase leak during the first week (marker of IRI) and MEAF were similar between groups. These findings persisted after propensity matching. Histology showed more hepatocyte vacuolization and higher Suzuki score in HOPE-LTs. Although this analysis could have been underpowered, no trends supporting the benefit of HOPE on liver and renal injury after LT were ever identified.

CONCLUSIONS

In conclusion, HOPE in this group of older donors does not seem to improve either graft IRI, or the incidence of early AKI after LT.

Post-transplant biliary complications using liver grafts from deceased donors older than 70 years: Retrospective case-control study

BACKGROUND

The shortage of liver grafts and subsequent waitlist mortality led us to expand the donor pool using liver grafts from older donors.

AIM

To determine the incidence, outcomes, and risk factors for biliary complications (BC) in liver transplantation (LT) using liver grafts from donors aged > 70 years.

METHODS

Between January 1994 and December 31, 2019, 297 LTs were performed using donors older than 70 years. After excluding 47 LT for several reasons, we divided 250 LTs into two groups, namely post-LT BC (n = 21) and without BC (n = 229). This retrospective case-control study compared both groups.

RESULTS

Choledocho-choledochostomy without T-tube was the most frequent technique (76.2% in the BC group vs 92.6% in the non-BC group). Twenty-one patients (8.4%) developed BC (13 anastomotic strictures, 7 biliary leakages, and 1 non-anastomotic biliary stricture). Nine patients underwent percutaneous balloon dilation and nine required a Roux-en-Y hepaticojejunostomy because of dilation failure. The incidence of post-LT complications (graft dysfunction, rejection, renal failure, and non-BC reoperations) was similar in both groups. There were no significant differences in the patient and graft survival between the groups. Moreover, only three deaths were attributed to BC. While female donors were protective factors for BC, donor cardiac arrest was a risk factor.

CONCLUSION

The incidence of BC was relatively low on using liver grafts > 70 years. It could be managed in most cases by percutaneous dilation or Roux-en-Y hepaticojejunostomy, without significant differences in the patient or graft survival between the groups.

An Update on Usage of High-Risk Donors in Liver Transplantation

The ideal management for end stage liver disease, acute liver failure, and hepatocellular carcinoma (HCC), within specific criteria, is liver transplantation (LT). Over the years, there has been a steady increase in the candidates listed for LT, without a corresponding increase in the donor pool. Therefore, due to organ shortage, it has been substantially difficult to reduce waitlist mortality among patients awaiting LT. Thus, marginal donors such as elderly donors, steatotic donors, split liver, and donors after cardiac death (DCD), which were once not commonly used, are now considered. Furthermore, it is encouraging to see the passing of Acts, such as the HIV Organ Policy Equity (HOPE) Act, enabling further research and development in utilizing HIV grafts. Subsequently, the newer antivirals have aided in successful post-transplant period, especially for hepatitis C positive grafts. However, currently, there is no standardization, and protocols are center specific in the usage of marginal donors. Therefore, studies with longer follow ups are required to standardize its use.

Extended criteria grafts and emerging therapeutics strategy in liver transplantation. The unstable balance between damage and repair

Due to increasing demand for donor organs, "extended criteria" donors are increasingly considered for liver transplantation, including elderly donors and donors after cardiac death. The grafts of this subgroup of donors share a major risk to develop significant features of ischemia reperfusion injury, that may eventually lead to graft failure. Ex-situ machine perfusion technology has gained much interest in liver transplantation, because represents both a useful tool for improving graft quality before transplantation and a platform for the delivery of therapeutics directly to the organ. In this review, we survey ongoing clinical evidences supporting the use of elderly and DCD donors in liver transplantation, and the underlying mechanistic aspects of liver aging and ischemia reperfusion injury that influence graft quality and transplant outcome. Finally, we highlight evidences in the field of new therapeutics to test in MP in the context of recent findings of basic and translational research.

RISK FACTORS FOR POST-LIVER TRANSPLANT BILIARY COMPLICATIONS IN THE ABSENCE OF ARTERIAL COMPLICATIONS

BACKGROUND

- Biliary complications (BC) represent the most frequent complication after liver transplantation, up to 34% of cases.

AIM

To identify modifiable risk factors to biliary complications after liver transplantation, essential to decrease morbidity.

METHOD

Clinical data, anatomical characteristics of recipient and donors, and transplant operation features of 306 transplants with full arterial patency were collected to identify risk factors associated with BC.

RESULTS

BC occurred in 22.9% after 126 days (median) post-transplantation. In univariate analyses group 1 (without BC, n=236) and group 2 patients (with BC, n=70) did not differ on their general characteristics. BC were related to recipient age under 40y (p=0.029), CMV infection (p=0.021), biliary disease as transplant indication (p=0.018), lower pre-transplant INR (p=0.009), and bile duct diameter <3 mm (p=0.033). CMV infections occurred sooner in patients with postoperative biliary complications vs. control (p=0.07). In a multivariate analysis, only CMV infection, lower INR, and shorter bile duct diameter correlated with BC. Positive CMV antigenemia correlated with biliary complications, even when titers lied below the treatment threshold.

CONCLUSIONS

Biliary complications after liver transplantation correlated with low recipient INR before operation, bile duct diameter <3 mm, and positive antigenemia for CMV or disease manifestation. As the only modifiable risk factor, routine preemptive CMV inhibition is suggested to diminish biliary morbidity after liver transplant.

The Impact of Age and Luminal Preservation on the Development of Intestinal Preservation Injury in Rats

BACKGROUND

Organs from older donors are believed to withstand ischemia worse than those from younger donors. The effect of age on the development of intestinal preservation injury (IPI) is unclear.

METHODS

We compared the development of IPI in intestines from young (3 mo), adult (14 mo), and old (20 mo) rat donors and assessed if luminal preservation (LP) is effective in delaying IPI. Small intestines were perfused with, and stored in, preservation solution (Custodiol) with or without LP solution (polyethylene glycol 3350). IPI was studied using histology (Chiu score, Alcian blue staining), Western blot, and electrophysiological assessment (Ussing chamber) at 4, 8, and 14 hours.

RESULTS

Intestines of old rats did not show major histological alterations, whereas their aortas and kidneys revealed typical age-related changes (arteriosclerosis and glomerulosclerosis). Intestines from old rats fared similarly to their younger counterparts at all time points regarding preservation injury and goblet cells count. Intestines undergoing LP showed fewer histological signs of damage and higher goblet cells count when compared with samples without LP, regardless of donor age. Ussing chamber experiments indicated a time-dependent deterioration of all parameters studied, which was delayed by the use of LP.

CONCLUSIONS

Older intestines did not convincingly demonstrate a faster IPI compared with intestines from adult and young donors. The small differences between the age groups were nullified by the use of LP. LP significantly delayed the IPI in all age groups and may allow for longer preservation periods without an increased risk of mucosal damage.

Comorbidities and Age in Brain-Dead Donors and Liver Transplantation: A 15-Year Retrospective Investigation

OBJECTIVES

Although livers from older donors (> 70 y) have been shown to be increasingly more efficiently used for transplant, donor comorbidities are considered additional risk factors. This is quite intriguing as comorbidities are known to increase with advancing age in the donor population.

MATERIALS AND METHODS

We assessed whether age and donor comorbidities influenced liver procurement over a 15-year period in a cohort of 1702 brain-dead donors in Tuscany, Italy.

RESULTS

Over the study period, age of potential donors significantly increased (P = .02) as well as the proportion of patients who were > 55 years old. The incidence of hypertension, diabetes mellitus, and previously known coronary artery disease also significantly increased. We observed a progressive increase in the number of transplanted livers from donors with advancing age despite an increase in comorbidities. The highest incidences of traumatic brain injury and anoxic brain injury were observed in the youngest donors. Transaminase levels and use of vasoactive drugs were lower in donors who were ≥ 72 years old.

CONCLUSIONS

According to our results, criteria for liver donors have already changed. Although age does not seem to be a limiting factor, older donors deserve a more accurate donor selection due to the higher incidence of risk factors (primarily diabetes mellitus).

Grafts from selected deceased donors over 80 years old can safely expand the number of liver transplants: A systematic review and meta-analysis

AIM

The aim of this systematic review and meta-analysis was to present the outcome of deceased adult liver transplantation from octogenarian (≥80 years old) donors compared to younger grafts.

METHODS

A systematic search was performed on six databases to identify all available original papers that report the outcome of adult recipients who underwent liver transplantation from a deceased octogenarian donor.

RESULTS

Overall, 39,034 liver transplantations from 12 studies were reported with 789 (2.02%) cases receiving grafts from octogenarian donors. Eight studies were included in the meta-analysis. There was no difference regarding the one, three, and five-year graft and patient survival between the recipients of livers <80 years old and octogenarian grafts. There were significantly more episodes of biliary complications in the recipients of octogenarian grafts (34/459; 7.4%) in comparison to the recipients of livers <80 years old (372/37074; 1.0%) (OR 0.53; 95% CI = 0.35-0.81; P 0.004; I² = 0%). The incidence of primary non-function, vascular complications and re-transplantation did not differ between groups.

CONCLUSIONS

The short- and medium-term graft and patient survival of octogenarian liver transplantation is not inferior compared to the liver transplantation with younger grafts, however with a higher rate of biliary complications.

The peculiar aging of human liver: A geroscience perspective within transplant context

An appraisal of recent data highlighting aspects inspired by the new Geroscience perspective are here discussed. The main findings are summarized as follows: i) liver has to be considered an immunological organ, and new studies suggest a role for the recently described cells named telocytes; ii) the liver-gut axis represents a crucial connection with environment and life style habits and may influence liver diseases onset; iii) the physiological aging of liver shows relatively modest alterations. Nevertheless, several molecular changes appear to be relevant: a) an increase of microRNA-31-5p; -141-3p; -200c-3p expressions after 60 years of age; b) a remodeling of genome-wide DNA methylation profile evident until 60 years of age and then plateauing; c) changes in transcriptome including the metabolic zones of hepatocyte lobules; d) liver undergoes an accelerated aging in presence of chronic inflammation/liver diseases in a sort of continuum, largely as a consequence of unhealthy life styles and exposure to environmental noxious agents. We argue that chronic liver inflammation has all the major characteristics of "inflammaging" and likely sustains the onset and progression of liver diseases. Finally, we propose to use a combination of parameters, mostly obtained by omics such as transcriptomics and epigenomics, to evaluate in deep both the biological age of liver (in comparison with the chronological age) and the effects of donor-recipient age-mismatches in the context of liver transplant.

Recipient Outcomes with Younger Donors Undergoing Living Donor Liver Transplantation

Introduction

The impact of donor age on liver transplantation is well known. Data on an appropriate donor age cut-off for living donor liver transplantation (LDLT) with a background of hepatitis C (HCV) is generally limited. The objective of this study was to determine whether limiting donor age to less than 35 years improved outcomes in patients with HCV-related end-stage liver disease (ESLD).

Methods

This was a retrospective review of 169 patients who underwent LDLT for HCV-related ESLD. The patients were divided into two groups based on whether they received grafts from donors ≤ 35 (Group 1) or > 35 (Group 2) years of age. Kaplan Meier curves were used to determine survival. Uni and multivariate analysis were performed to determine independent predictors of mortality.

Results

Mean donor age was 25.1 ± 5.2 and 40.1 ± 3.4 years (P < 0.0001). Early allograft dysfunction (EAD) was seen in 11.7% patients in Group 1 versus 29.6% in Group 2 (P = 0.02). A significant difference in mortality was present between the two groups, i.e., 33.3% versus 15.8% (P = 0.04). The estimated four-year overall survival (OS) was 78% and 64% (P = 0.03). Upon doing univariate analysis, the donor age (P = 0.04) and EAD (P = 0.006) were found to be significant variables for mortality. On multivariate analysis, EAD was the only independent predictor of mortality (Hazard ratio: 2.6; confidence interval: 1.1 - 5.8; P = 0.01).

Conclusion

Opting for younger donors (≤ 35 years) for HCV-related ESLD patients lowers the risk of EAD and improves overall survival.

Liver Donation From Marginal Donors: To Donate or Not to Donate?

OBJECTIVES

Livers from deceased donors compose nearly 30% of all organ transplants, and about 700 liver transplants are carried out per year. Marginal livers (extended-criteria donors), however, are not usually accepted by recipient teams, and there is only one center for these procedures in Iran. The final decision is made according to criteria that are much more conservative than other globally accepted ones.

MATERIALS AND METHODS

To find significant differences and construct an algorithm to predict the future of marginal livers (before transfer of donors to our organ procurement unit), successfully donated and unsuccessfully donated livers divided into 2 age groups were compared in terms of age, sex, body mass index, liver function tests, significant medical disorders, and preretrieval liver sonography report.

RESULTS

In the first age group (50-59 years old), there were 88 successful donors and 27 unsuccessful cases (due to 3 reasons: positive virology tests, death before retrieval, and ruled out by surgeons in the operating room). In the second age group (? 60 years old), there were 45 successful donors and 11 unsuccessful cases. The results showed that there were no differences between successful and unsuccessful cases regarding age and liver sonography results; however, sex, body mass index, liver function tests, and previous medical disorder were different between groups. Donors in both age groups were mostly male (60% and 73%); however, surprisingly, most unsuccessful cases were female (56.6% and 57%). Donors had generally lower body mass index (2 numerical difference), better liver function tests, and less risk factors (heart disease, diabetes mellitus, fatty liver, and chronic alcohol consumption).

CONCLUSIONS

Before transfer of marginal liver donors to the organ procurement unit for further evaluation and organ retrieval, one must consider that age is just a number and the presence of other comorbidities can have more decisive roles on liver quality.

Optimizing the Use of Geriatric Livers for Transplantation in the Eurotransplant Region

Acceptance criteria for liver allografts are ever more expanding because of a persisting wait-list mortality. Older livers are therefore offered and used more frequently for transplantation. This study aims to analyze the use and longterm outcome of these transplantations. Data were included on 17,811 first liver transplantations (LTs) and information on livers that were reported for allocation but not transplanted from 2000 to 2015 in the Eurotransplant (ET) region. Graft survival was defined as the period between transplantation and date of retransplantation or date of recipient death. In the study period, 2394 (13%) transplantations were performed with livers ≥70 years old. Graft survival was 74%, 57%, and 41% at 1-, 5-, and 10-year follow-up, respectively. A history of diabetes mellitus in the donor (hazard ratio [HR], 1.3; P = 0.01) and positive hepatitis C virus antibody in the recipient (HR, 1.5; P < 0.001) are specific risk factors for transplantations with livers ≥70 years old. Although donor age is associated with a linearly increasing risk of graft loss between 25 and 80 years old, no difference in graft survival could be observed when "preferred" recipients were transplanted with a liver <70 or ≥70 years old (HR 1.1; CI 0.92-1.23, P = 0.40) or with a donor <40 or ≥70 years old (HR 1.2; CI 0.96-1.37, P = 0.13). Utilization of reported livers ≥70 years old increased from 42% in 2000-2003 to 76% in 2013-2015 without a decrease in graft survival (P = 0.45). In conclusion, an important proportion of LTs in the ET region are performed with livers ≥70 years old. The risk of donor age on graft loss increases linearly between 25 and 80 years old. Livers ≥70 years old can, however, be transplanted safely in preferred patients and are to be used more frequently to further reduce wait-list mortality.

Outcome after liver transplantation in elderly recipients (>65 years) - A single-center retrospective analysis

BACKGROUND

Liver transplantation (LT) in elderly recipients is controversially discussed in the literature with only little data on long-term outcome available. We aimed to evaluate the safety and efficiency of LT in elderly recipients (>65 years).

METHODS

Between 1989-2016, 139 patients >65 years-old were listed for liver transplantation, and 76 (55%) were transplanted. Patient outcome and characteristics were evaluated separately for the time period before (1989-2004) and after (2005-2016) MELD-implementation. Post-transplant outcome was compared between the elderly cohort and LT-recipients aged 18-65 years (n = 1395).

RESULTS

Overall survival of patients >65 years was better in the MELD-era compared to the earlier period (1- and 5-year-survival: 73%, 60% vs. 69%, 37%, respectively; p = 0.055). The main differences between the two groups included higher recipient age (p = 0.001) and BMI (p = 0.001), higher donor age (p < 0.001), less need of intraoperative red blood cells (p = 0.008) and a lower number of postoperative rejections (p = 0.03) after 2004. Comparing the overall survival of patients transplanted in the MELD-era aged 18-65 years vs. >65 years displayed comparable 1- and 5 year-survival rates (81%, 68% vs. 73% and 60%, respectively, p = 0.558).

CONCLUSION

In the modern era, outcome of patients receiving LT with >65 years is comparable to <65 year-old patients. After careful evaluation, patients >65 years old should be considered for LT.

Orthotopic Liver Transplantation: Preliminary Analysis of Complications With Grafts From Elderly Donors

OBJECTIVE

This study aims to determine if donor grafts of patients older than 65 years develop more post-transplantation complications than those of younger patients.

DESIGN

This is a retrospective, observational study of liver transplant recipients during 12 months in Virgen del Rocio University Hospital. We compare incidence rates of reperfusion syndrome, acute kidney injury, and need for intra- and postoperative red blood cell transfusions in two donor age groups in which group A is <65 years old and group B is ≥65 years old.

RESULTS

Sixty cases were included. Reperfusion syndrome, acute kidney injury, and both intra- and postoperative red blood cell transfusion were more frequent in group A than group B (11.4% vs. 4%, P = .390; 44% vs. 32%, P = .423; 68.8% vs. 48%, P = .120; and 70.6% vs. 64%, P = .779, respectively). Six recipients (17.1%) died at 12 months from group A whereas there were no deaths register in group B during that time (P = .036).

CONCLUSION

Our results showed that including elderly donors does not aggravate incidence of complications, emphasizing that advanced age should not be an exclusion criteria for liver transplantation.

Orthotopic Liver Transplantation With Elderly Donors (Over 80 Years of Age): A Prospective Evaluation

BACKGROUND

Our main objective was to assess the clinical outcomes obtained in a single orthotopic liver transplant (OLT) hospital with donors ≥80 years of age compared to a control group of patients subjected to OLT during the same period of time with donors who were under 65 years of age.

METHODS

A prospective analysis was carried out on all the OLTs performed using liver grafts from donors in a state of brain death and with an age of ≥80 years (study group) between April 2007 and January 2015. The results of the study group (n = 36) were compared with those of a control group of patients less than 65 years of age receiving transplants with grafts.

RESULTS

A total of 51 potential donors ≥80 years were assessed, with a total of 36 liver transplants being carried out and their results were compared with a control group of 283 patients receiving transplants. The median follow-up time of the patients in the series was 36 months (range: 24-120 months). Graft survival at 1, 2, and 3 years was 77%, 72%, and 62%, respectively, among the patients in the study group and 79%, 73%, and 65% among the patients in the control group, and there were no statistically significant differences. Patient survival at 1, 2, and 3 years was 86%, 82%, and 75%, respectively, among the patients in the study group and 82%, 76%, and 72% among the patients in the control group, also without there being any statistically significant differences.

CONCLUSIONS

There is no age limit for liver transplant donors. The use of octogenarian donors makes it possible to increase the pool of donors while providing enough safety for the recipient.

Elderly donor graft for liver transplantation: Never too late

The definitive treatment for end stage liver disease remains a liver transplant and hence livers are needed for these patients along with cases of acute fulminant liver failure. Hence livers are a scarce and highly valuable commodity in the current time. By extending the pool of donors to include the elderly livers, it allows for increased availability of donors and reduces the mortality that is associated with the waiting list itself. There is an increasing prevalence of end stage liver disease due to conditions like chronic hepatitis B and C, non-alcoholic steatohepatitis, alcoholic liver disease. Many studies show non-inferior outcomes when elderly livers are used as a vigorous selection process is implemented. The process takes into account the characteristics of the donor, graft and recipient allowing for appropriate donor-recipient coupling. To meet the increasing demands of livers, elderly donors should be utilized for liver transplantation. The aim of this review article is to describe the aging process of the liver and the outcomes associated with use of elderly livers for transplantation.

Liver Transplantation Results by Donor Age

OBJECTIVE

The objective of this study was to compare liver transplantation outcomes as a function of donor age.

MATERIAL AND METHODS

We performed 212 liver transplantations between 2008 and 2014. We described a prospective cohort study and grouped the patients by liver donor age. We compared quantitative and categorical variables using statistical analysis.

RESULTS

No statistically significant differences were found among any graft age groups in gender (always more males), time on waiting list, age, height, Child Pugh Turcotte (CHILD) score, Model for End-stage Liver Disease (MELD) score, need for intraoperative blood products, or intensive care unit stay. The most frequent etiology of liver failure was alcohol. A brain-dead donor was the most frequent type in all groups. The whole graft was used except in 4 cases. No statistically significant differences were found among groups in the surgical technique, postreperfusion syndrome, arterial complications, biliary complications, venous complications, acute rejection, and retransplantation. The 3-year patient survival rate was 64% in the <60-year graft age group, 48% in the 60- to 69-year group, 64% in the 70- to 79-year group, and 40% in the ≥80-year group (P = .264). The 3-year graft survival rate was 62% in the <60-year graft age group, 47% in the 60- to 69-year group, 65% in the 70- to 79-year group, and 40% in the ≥80-year group (P = .295).

CONCLUSIONS

Given the need to increase the pool of liver donors, older donors should be considered as a source for liver transplantation, although careful selection is required.

Liver Transplantation With Older Donors: A Comparison With Younger Donors in a Context of Organ Shortage

BACKGROUND

Older liver grafts have been considered in the past decade due to organ shortage. The aim was to compare outcomes after liver transplantation with either younger or older donors.

METHODS

Patients transplanted in our center between 2004 and 2014 with younger donors (younger than 60 years; n = 253) were compared with older donors (older than 75 years; n = 157). Multiorgan transplantations, split grafts, or non-heart-beating donors were not included.

RESULTS

Donors in the older group were mostly women deceased from stroke, and only 3 patients had experienced cardiac arrest. Liver tests were significantly better in the older group than in the younger group. There was no difference regarding cold ischemia time, model for end-stage liver disease score, and steatosis. There was no significant difference regarding primary nonfunction and dysfunction, hepatic artery and biliary complications, and retransplantation rates. Graft survival was not different (65% and 64% in the older and younger groups, P = 0.692). Within the older group, hepatitis C infection, retransplantation, and emergency transplantation were associated with poor graft survival.

CONCLUSIONS

Provided normal liver tests and the absence of cardiac arrest in donors, older liver grafts (>75 years) may be safely attributed to non-hepatitis C-infected recipients in the setting of a first and nonurgent transplantation.

Identification of miR-31-5p, miR-141-3p, miR-200c-3p, and GLT1 as human liver aging markers sensitive to donor-recipient age-mismatch in transplants

To understand why livers from aged donors are successfully used for transplants, we looked for markers of liver aging in 71 biopsies from donors aged 12–92 years before transplants and in 11 biopsies after transplants with high donor–recipient age‐mismatch. We also assessed liver function in 36 age‐mismatched recipients. The major findings were the following: (i) miR‐31‐5p, miR‐141‐3p, and miR‐200c‐3p increased with age, as assessed by microRNAs (miRs) and mRNA transcript profiling in 12 biopsies and results were validated by RT–qPCR in a total of 58 biopsies; (ii) telomere length measured by qPCR in 45 samples showed a significant age‐dependent shortage; (iii) a bioinformatic approach combining transcriptome and miRs data identified putative miRs targets, the most informative being GLT1, a glutamate transporter expressed in hepatocytes. GLT1 was demonstrated by luciferase assay to be a target of miR‐31‐5p and miR‐200c‐3p, and both its mRNA (RT–qPCR) and protein (immunohistochemistry) significantly decreased with age in liver biopsies and in hepatic centrilobular zone, respectively; (iv) miR‐31‐5p, miR‐141‐3p and miR‐200c‐3p expression was significantly affected by recipient age (older environment) as assessed in eleven cases of donor–recipient extreme age‐mismatch; (v) the analysis of recipients plasma by N‐glycans profiling, capable of assessing liver functions and biological age, showed that liver function recovered after transplants, independently of age‐mismatch, and recipients apparently ‘rejuvenated’ according to their glycomic age. In conclusion, we identified new markers of aging in human liver, their relevance in donor–recipient age‐mismatches in transplantation, and offered positive evidence for the use of organs from old donors.

How important is donor age in liver transplantation?

The age of liver donors has been increasing in the past several years because of a donor shortage. In the United States, 33% of donors are age 50 years or older, as are more than 50% in some European countries. The impact of donor age on liver transplantation (LT) has been analyzed in several studies with contradictory conclusions. Nevertheless, recent analyses of the largest databases demonstrate that having an older donor is a risk factor for graft failure. Donor age is included as a risk factor in the more relevant graft survival scores, such as the Donor Risk Index, donor age and Model for End-stage Liver Disease, Survival Outcomes Following Liver Transplantation, and the Balance of Risk. The use of old donors is related to an increased rate of biliary complications and hepatitis C virus-related graft failure. Although liver function does not seem to be significantly affected by age, the incidence of several liver diseases increases with age, and the capacity of the liver to manage or overcome liver diseases or external injuries decreases. In this paper, the importance of age in LT outcomes, the role of donor age as a risk factor, and the influence of aging on liver regeneration are reviewed.