Liver and intestine transplantation: summary analysis, 1994–2003

With nearly two years of data available since the inception of the MELD and PELD allocation system, this article examines national OPTN/SRTR data to describe trends in waiting list composition, waiting list mortality, transplant rates, and patient and graft outcomes for liver transplantation.
Following a 6% reduction in the size of the waiting list after MELD was implemented in 2002, the number of patients on the waiting list grew by 2% from 2002 to 2003, while the number of liver transplants increased by 6%. The overall death rate while on the liver waiting list has decreased from 225 deaths per 1,000 patient years in 1994 to 124 deaths in 2003. As with the waiting list death rates, post-transplant death rates have also decreased over the past decade. Unadjusted one-year patient survival was lower for older donor age groups (88% for donors aged 18–34, 87% for donors aged 35–49, 85% for donors aged 50-64); a similar trend was observed at three and five years following transplantation.
Intestine transplantation is performed with slowly increasing frequency and success. Early graft losses and rejection rates have changed little since 1994, but rejection is easier to control and long-term survival is improving.     

Liver and Intestine Transplantation in the United States, 1995–2004

Three years of survival data are now available and the impact of the model for end-stage liver disease (MELD) allocation system is becoming clear. After a decline in new registrants to the waiting list in 2002, the number increased to 10 856 new patients in 2004. Since the implementation of MELD, the percentage of patients who have been on the list for 1–2 years has declined from 24% to 19%. There has been a shift upward in the percentage of patients with higher MELD scores on the waiting list.
An increasing percentage of adult living donor liver recipients are over the age of 50 years; from 1% in 1997 to 51% in 2004. Parents donating to children (93% of living donors in 1995), represented only 14% in 2004. Long-term adjusted patient survival declined with increasing recipient age in adults following either DDLT or LDLT.
Cirrhosis caused by chronic hepatitis C virus (HCV) is the leading indication for liver transplantation and is associated with reduced long-term survival in recipients with HCV compared to those without HCV, 68% at 5 years compared to 76%.
Although the intestine waiting list has more than doubled over the last decade, an increasing number of centers now perform intestinal transplantation with greater success.     

Kidney and pancreas transplantation

Data from the Scientific Registry of Transplant Recipients offer a unique and comprehensive view of US trends in kidney and pancreas waiting list characteristics and outcomes, transplant recipient and donor characteristics, and patient and allograft survival. Important findings from our review of developments during 2002 and the decade's transplantation trends appear below.
The kidney waiting list has continued to grow, increasing from 47 830 in 2001 to 50 855 in 2002. This growth has occurred despite the increasing importance of living donor transplantation, which rose from 28% of total kidney transplants in 1993 to 43% in 2002.
Policies and procedures to expedite the allocation of expanded criteria donor (ECD) kidneys were developed and implemented during 2002, when 15% of deceased donor transplants were performed with ECD kidneys. Unadjusted 1- and 5-year deceased donor kidney allograft survivals were 81% and 51% for ECD kidney recipients, and 90% and 68% for non-ECD kidney recipients, respectively.
Although more patients have been placed on the simultaneous kidney-pancreas waiting list, the number of these transplants dropped from a peak of 970 in 1998 to 905 in 2002. This decline may be due to competition for organs from increasing numbers of isolated pancreas and islet transplants.     

Impact of Adult Living Donor Liver Transplantation on Waiting Time Survival in Candidates Listed for Liver Transplantation

Studies comparing adult living donor liver transplantation to deceased donor liver transplantation have focused on post-transplant survival. Our aim was to focus on the impact of living donor liver transplant on waiting time mortality and overall mortality. We analyzed the affect of living donor liver transplantation on waiting time mortality and overall mortality (from listing until last follow up) in a cohort of 116 transplant candidates. Fifty-eight candidates who had individuals present as potential living donors (volunteer group) were matched by MELD score to 58 liver transplant candidates who did not have individuals present as a potential living donor (no volunteer group). Twenty-seven percent of candidates in the no volunteer group and 62% of candidates in the volunteer group underwent liver transplantation, p = 0.0003. One-year waiting list mortality for the volunteer group and no volunteer group was 10% and 20%, respectively, p = 0.03. Patient survival from the time of listing to last follow up was similar between the two groups. In our study group, living donor liver transplantation is associated with a higher rate of liver transplantation and lower waiting time mortality. In the era of living donor liver transplantation, estimates of patient survival should incorporate waiting time mortality.     

Thoracic organ transplantation in the United States, 1994–2003

Using OPTN/SRTR data, this article reviews the state of thoracic organ transplantation in 2003 and the previous decade. Time spent on the heart waiting list has increased significantly over the last decade. The percentage of patients awaiting heart transplantation for >2 years increased from 23% in 1994 to 49% by 2003. However, there has been a general decline in heart waiting list death rates over the decade. In 2003, the lung transplant waiting list reached a record high of 3,836 registrants, up slightly from 2002 and more than threefold since 1994. One-year patient survival for those receiving lungs in 2002 was 82%, a statistically significant improvement from 2001 (78%). The number of patients awaiting a heart-lung transplant, declining since 1998, reached 189 in 2003. Adjusted patient survival for heart-lung recipients is consistently worse than the corresponding rate for isolated lung recipients, primarily due to worse outcomes for heart-lung recipients with congenital heart disease. A new lung allocation system, approved in June 2004, derives from the survival benefit of transplantation with consideration of urgency based on waiting list survival, instead of being based solely on waiting time. A goal of the policy is to minimize deaths on the waiting list.     

Liver and Intestine Transplantation in the United States, 1997–2006

Liver transplantation in 2006 generally resembled previous years, with fewer candidates waiting for deceased donor liver transplants (DDLT), continuing a trend initiated with the implementation of the model for end-stage liver disease (MELD). Candidate age distribution continued to skew toward older ages with fewer children listed in 2006 than in any prior year. Total transplants increased due to more DDLT with slightly fewer living donor liver transplants (LDLT). Waiting list deaths and time to transplant continued to improve. In 2006, there also were fewer DDLT for patients with MELD <15, fewer pediatric Status 1A/B transplants and more transplants from donation after cardiac death (DCD) donors. Adjusted patient and graft survival rates were similar for LDLT and DDLT. This article also contains in-depth analyses of transplantation for hepatocellular carcinoma (HCC). Recipients with HCC had lower adjusted 3-year posttransplant survival than recipients without HCC. HCC recipients who received pretransplant ablative treatments had superior adjusted 3-year posttransplant survival compared to HCC recipients who did not. Intestinal transplantation continued to slowly increase with the largest number of candidates on the waiting list since 1997. Survival rates have increased over time. Small children waiting for intestine grafts continue to have the highest waiting list mortality.     

Organ allocation in pediatric transplantation in France

In France, ministerial decrees in 1995 and 1996 gave children under 16 who are awaiting transplantation national priority for kidneys and livers from donors under 16, and regional priority for kidneys and livers from donors under 30. We analyzed the effects of these changes on waiting time, death on the waiting list, and balance between demand and supply. The percentage of children who received a transplant during the year of registration increased from 40% in 1993 to 67% in 1998 for kidney transplantation, but only from 50% to 67% for liver transplantation. The number of new children registered on the renal transplant waiting list (84 in 1998) and the number transplanted (85 in 1998) are balanced. But, because of the number of children still on the waiting list at the end of each year, there remains an imbalance of about 70 for kidney transplantation. For liver transplantation, there remains an imbalance of about 35. Death on the renal transplant waiting list has been below 2% since 1993. Death on the liver transplant waiting list decreased from 10–20% in 1993–1995 to 3% in 1998. The number of children who died on the thoracic organ waiting list in 1998 was the same as the number transplanted. In conclusion, the new rules governing organ allocation to children in France have shortened waiting time for renal transplantation, but not for liver transplantation. Many children still die on the waiting list for thoracic organ transplantation. Received: 4 July 2001 / Revised: 4 October 2001 / Accepted: 4 October 2001     

Dynamic changes in MELD score not only predict survival on the waiting list but also overall survival after liver transplantation

The predictive value of MELD score for post‐transplant survival has been under constant debate since its implementation in 2001. Aim of this study was to assess the impact of alterations in MELD score throughout waiting time (WT) on post‐transplant survival. A single‐centre retrospective analysis of 1125 consecutive patients listed for liver transplantation between 1997 and 2009 was performed. The impact of MELD score and dynamic changes in MELD score (DeltaMELD), as well as age, sex, year of listing and WT were evaluated on waiting list mortality and post‐transplant survival. In this cohort, 539 (60%) patients were transplanted, 223 (25%) died on list and 142 (15%) were removed from the waiting list during WT. One‐, three‐ and five‐year survival after liver transplantation were 83%, 78% and 76% respectively. DeltaMELD as a continuous variable proved to be the only significant risk factor for overall survival after liver transplantation (hazard ratio (HR): 1.06, 95% confidence interval (CI) 1.02–1.1, P = 0.013). The highest risk of post‐transplant death could be defined for patients with a DeltaMELD > 10 (HR: 4.87, 95% CI 2.09–11.35, P < 0.0001). In addition, DeltaMELD as well as MELD at listing showed a significant impact on waiting list mortality. DeltaMELD may provide an easy evaluation tool to identify patients on the liver transplant waiting list with a high mortality risk after transplantation in the current setting. Temporarily withholding and re‐evaluating these patients might improve overall outcome after liver transplantation.     

Pediatric transplantation

Analysis of the OPTN/SRTR database demonstrates that, in 2002, pediatric recipients accounted for 7% of all recipients, while pediatric individuals accounted for 14% of deceased organ donors. For children fortunate enough to receive a transplant, there has been continued improvement in outcomes following all forms of transplantation. Current 1-year graft survival is generally excellent, with survival rates following transplantation in many cases equaling or exceeding those of all other recipients. In renal transplantation, despite excellent early graft survival, there is evidence that long-term graft survival for adolescent recipients is well below that of other recipients. A causative role for noncompliance is possible. While the significant improvements in graft and patient survival are laudable, waiting list mortality remains excessive. Pediatric candidates awaiting liver, intestine, and thoracic transplantation face mortality rates generally greater than those of their adult counterparts. This finding is particularly pronounced in patients aged 5 years and younger. While mortality awaiting transplantation is an important consideration in refining organ allocation strategies, it is important to realize that other issues, in addition to mortality, are critical for children. Consideration of the impact of end-stage organ disease on growth and development is often equally important, both while awaiting and after transplantation.     

Liver and Intestine Transplantation in the United States 1998–2007

Liver transplantation numbers in the United States remained constant from 2004 to 2007, while the number of waiting list candidates has trended down. In 2007, the waiting list was at its smallest since 1999, with adults ≥50 years representing the majority of candidates. Noncholestatic cirrhosis was most commonly diagnosed. Most age groups had decreased waiting list death rates; however, children <1 year had the highest death rate. Use of liver allografts from donation after cardiac death (DCD) donors increased in 2007. Model for end-stage liver disease (MELD)/pediatric model for end-stage liver disease (PELD) scores have changed very little since 2002, with MELD/PELD <15 accounting for 75% of the waiting list. Over the same period, the number of transplants for MELD/PELD <15 decreased from 16.4% to 9.8%. Hepatocellular carcinoma exceptions increased slightly. The intestine transplantation waiting list decreased from 2006, with the majority of candidates being children <5 years old. Death rates improved, but remain unacceptably high. Policy changes have been implemented to improve allocation and recovery of intestine grafts to positively impact mortality. In addition to evaluating trends in liver and intestine transplantation, we review in depth, issues related to organ acceptance rates, DCD, living donor transplantation and MELD/PELD exceptions.     

Pediatric transplantation, 1994–2003

This article uses OPTN/SRTR data to review trends in pediatric transplantation over the last decade. In 2003, children younger than 18 made up 3% of the 82,885 candidates for organ transplantation and 7% of the 25,469 organ transplant recipients. Children accounted for 14% of the 6,455 deceased organ donors. Pediatric organ transplant recipients differ from their adult counterparts in several important aspects, including the underlying etiology of organ failure, the complexity of the surgical procedures, the pharmacokinetic properties of common immunosuppressants, the immune response following transplantation, the number and degree of comorbid conditions, and the susceptibility to post-transplant complications, especially infectious diseases. Specialized pediatric organ transplant programs have been developed to address these special problems, The transplant community has responded to the particular needs of children and has provided them special consideration in the allocation of deceased donor organs. As a result of these programs and protocols, children are now frequently the most successful recipients of organ transplantation; their outcomes following kidney, liver, and heart transplantation rank among the best. This article demonstrates that substantial improvement is needed in several areas: adolescent outcomes, outcomes following intestine transplants, and waiting list mortality among pediatric heart and lung candidates,     

Kidney and Pancreas Transplantation in the United States, 1995–2004

This article examines OPTN/SRTR data on kidney and pancreas transplantation for 2004 and the previous decade, and discusses recent changes in kidney-pancreas (KP) allocation policy and emerging issues in kidney donation after cardiac death (DCD). Although the number of kidney donors continues to increase, new waiting list registrations again outpaced the number of kidney transplants performed, rising by 11% between 2003 and 2004 and contributing to a 1-year increase of 8% in the number of patients active on the waiting list. DCD has increased steadily since 2000; 39% more DCD transplants were performed in 2004 than 2003. Both deceased donor and living donor kidney graft survival rates remain excellent and are improving. The number of people living with a functioning kidney transplant doubled between 1995 and 2004, to 101 440 with a functioning kidney-alone and 7213 with a functioning KP. Health care providers in all settings are more likely to be exposed to these transplant recipients. Patient survival following simultaneous pancreas-kidney (SPK) transplantation is excellent and has improved incrementally since 1995; death rates in the first year fell from 60 per 1000 patient-years at risk in 2001 to 45 in 2003. The number of solitary pancreas transplants increased dramatically in 2004.     

Thoracic organ transplantation

This article presents an overview of factors associated with thoracic transplantation outcomes over the past decade and provides valuable information regarding the heart, lung, and heart-lung waiting lists and thoracic organ transplant recipients. Waiting list and post-transplant information is used to assess the importance of patient demographics, risk factors, and primary cardiopulmonary disease on outcomes.
The time that the typical listed patient has been waiting for a heart, lung, or heart-lung transplant has markedly increased over the past decade, while the number of transplants performed has declined slightly and survival after transplant has plateaued. Waiting list mortality, however, appears to be declining for each organ and for most diseases and high-severity subgroups, perhaps in response to recent changes in organ allocation algorithms. Based on perceived inequity in organ access and in response to a mandate from Health Resources and Services Administration, the lung transplant community is developing a lung allocation system designed to minimize deaths on the waiting list while maximizing the benefit of transplant by incorporating post-transplant survival and quality of life into the algorithm. Areas where improved data collection could inform evolving organ allocation and candidate selection policies are emphasized.     

Adult Living Donor Liver Transplantation

Adult living donor liver transplantation (LDLT) begun in response to deceased donor organ shortage and waiting list mortality, grew rapidly after its first general application in the United States in 1998. There are significant risks to the living donor, including the risk of death and substantial morbidity, and two highly publicized donor deaths have led to decreased LDLT since 2001. Significant improvements in outcomes have been seen over recent years that have not been reported in single center studies; however, LDLT still comprises less than 5% of adult liver transplants, significantly less than in kidney transplantation where living donors now comprise the majority. The ethics, optimal utility and application of LDLT remain to be defined. In addition, studies to date have focused on post-transplant outcomes and not included the potential impact of LDLT on waiting time mortality. Future analyses should include appropriate control or comparison groups that capture the effect of LDLT on overall mortality from the time of listing. Further growth of LDLT will depend on defining the optimal recipient and donor characteristics for this procedure as well as broader acceptance and experience in the public and in transplant centers.     

The Survival Benefit of Liver Transplantation

Demand for liver transplantation continues to exceed donor organ supply. Comparing recipient survival to that of comparable candidates without a transplant can improve understanding of transplant survival benefit. Waiting list and post-transplant mortality was studied among a cohort of 12 996 adult patients placed on the waiting list between 2001 and 2003. Time-dependent Cox regression models were fitted to determine relative mortality rates for candidates and recipients. Overall, deceased donor transplant recipients had a 79% lower mortality risk than candidates (HR = 0.21; p < 0.001). At Model for End-stage Liver Disease (MELD) 18-20, mortality risk was 38% lower (p < 0.01) among recipients compared to candidates. Survival benefit increased with increasing MELD score; at the maximum score of 40, recipient mortality risk was 96% lower than that for candidates (p < 0.001). In contrast, at lower MELD scores, recipient mortality risk during the first post-transplant year was much higher than for candidates (HR = 3.64 at MELD 6-11, HR = 2.35 at MELD 12-14; both p < 0.001). Liver transplant survival benefit at 1 year is concentrated among patients at higher risk of pre-transplant death. Futile transplants among severely ill patients are not identified under current practice. With 1 year post-transplant follow-up, patients at lower risk of pre-transplant death do not have a demonstrable survival benefit from liver transplant.     

Liver and Intestine Transplantation in the United States, 1996–2005

The number of liver transplants performed yearly has slowly and steadily increased over the last 10 years, reaching 6441 procedures in 2005. The number of living donor liver transplants performed rose steadily from 1996 to 2001, when it peaked at 519; since 2003 there have been approximately 320 such procedures performed each year. The continual increase in the size of the waiting list for a liver transplant, which peaked in 2001 at 14 897 patients, was interrupted in 2002 by the implementation of the allocation system based on the model for end-stage liver disease and pediatric end-stage liver disease (MELD/PELD). Activity in all areas of intestinal transplantation continues to increase. One-year patient and graft survival following intestine-alone transplantation now seem to be superior to outcomes following liver-intestine transplantation. Other topics covered here include the recent 'Share 15' component of the MELD allocation system; liver transplantation following donation after cardiac death; simultaneous liver-kidney transplantation and waiting list and post-transplant outcomes for both liver and intestine transplantation, broken out by a variety of clinical and demographic factors.     

Pediatric Transplantation in the United States, 1996–2005

Solid organ transplantation is accepted as a standard lifesaving therapy for end-stage organ failure in children. This article reviews trends in pediatric transplantation from 1996 to 2005 using OPTN data analyzed by the Scientific Registry of Transplant Recipients. Over this period, children have contributed significantly to the donor pool, and although the number of pediatric donors has fallen from 1062 to 900, this still accounts for 12% of all deceased donors. In 2005, 2% of 89 884 candidates listed for transplantation were less than 18 years old; in 2005, 1955 children, or 7% of 28 105 recipients, received a transplant. Improvement in waiting list mortality is documented for most organs, but pretransplant mortality, especially among the youngest children, remains a concern. Posttransplant survival for both patients and allografts similarly has shown improvement throughout the period; in most cases, survival is as good as or better than that seen in adults. Examination of immunosuppressive practices shows an increasing tendency across organs toward tacrolimus-based regimens. In addition, use of induction immunotherapy in the form of anti-lymphocyte antibody preparations, especially the interleukin-2 receptor antagonists, has increased steadily. Despite documented advances in care and outcomes for children undergoing transplantation, several considerations remain that require attention as we attempt to optimize transplant management.     

Effect of the COVID-19 Pandemic on Organ Donation and Transplantation in São Paulo,Brazil

The COVID-19 pandemic has affected donation and transplantation activities in São Paulo, Brazil, as well as the patients receiving these organs. In this study, information from the database of the São Paulo Organ Allocation System was analyzed and compared 2 periods—before the pandemic and during the pandemic—to identify this effect. The COVID-19 pandemic interfered in the mortality rate and the time on the waiting list for heart, liver, pancreas, lung, and kidney transplants; the number of effective donors; and the use or disposal of available organs from deceased donors. It also reduced the transplant activity with living donors. Regarding the activity of eye tissue transplantation, the time on the waiting list increased and the number of transplant procedures decreased. The kidney transplant program was the most affected in our study. There was an increase in waiting time and mortality in the waiting list for this organ and also a decrease in kidney utilization rates.     

Prevalence and Outcomes of Multiple-Listing for Cadaveric Kidney and Liver Transplantation

Transplant candidates are permitted to register on multiple waiting lists. We examined multiple-listing practices and outcomes, using data on 81 481 kidney and 26 260 liver candidates registered between 7/1/95 and 6/30/00. Regression models identified factors associated with multiple-listing and its effect on relative rates of transplantation, waiting list mortality, kidney graft failure, and liver transplant mortality. Overall, 5.8% (kidney) and 3.3% (liver) of candidates multiple-listed. Non-white race, older age, non-private insurance, and lower educational level were associated with significantly lower odds of multiple-listing. While multiple-listed, transplantation rates were significantly higher for nearly all kidney and liver candidate subgroups (relative rate [RR]= 1.42-2.29 and 1.82-7.41, respectively). Waiting list mortality rates were significantly lower while multiple-listed for 11 kidney subgroups (RR = 0.22-0.72) but significantly higher for 7 liver subgroups (RR = 1.44-5.93), suggesting multiple-listing by healthier kidney candidates and sicker liver candidates. Graft failure was 10% less likely among multiple-listed kidney recipients. Multiple- and single-listed liver recipients had similar post-transplant mortality rates. Although specific factors characterize those transplant candidates likely to multiple-list, transplant access is significantly enhanced for almost all multiple-listed kidney and liver candidates.     

Transplantation in Canada: report of the Canadian Organ Replacement Register

The solid organ transplant rate in Canada grew from 49.5 per million population (PMP) in 1993 to 56.8 PMP in 2002, with a peak rate of 61.0 in 2000. Most of this increase was seen in living donor kidney, liver, and lung transplants where combined rates rose twofold, from 124.9 per 1000 transplants to 243.5. Despite this, the rate of organ transplantation in the United States was 150% that of Canada in 2002. As of December 31, 2002, there were 3,956 patients waiting for an organ transplant in Canada, an 84% increase in the total number of patients on the waiting list as of December 31, 1993, 10 years ago. Cadaveric organ donation did not change over this period. An international comparison of cadaveric organ donation rates for 2001 place Canada (13.5 PMP) well below Spain (32.5 PMP) and the United States (22.6 PMP) but above Australia (9.3 PMP). As a result the annual gap between transplants performed and the waiting list has grown from 927 in 1992 to 2230 in 2001, representing an annual increase of 8.3%.