Published online Sep 10, 2018. doi: 10.5500/wjt.v8.i5.167
Peer-review started: April 7, 2018
First decision: May 16, 2018
Revised: July 23, 2018
Accepted: August 3, 2018
Article in press: August 4, 2018
Published online: September 10, 2018
Processing time: 155 Days and 13.7 Hours
The long-term impacts of clinical advancements and policy interventions over the past two decades on liver transplant outcomes have been poorly studied.
The motivation for such a study is the vast amount of large data that are mandatorily reported from 1989 by all transplant institutions in the United States, from which key observations could be made for future policy changes in transplantation.
The objective of this study was to compare trends in donor/recipient characteristics and outcomes over time. Subjects included 70,377 adult first-time recipients of whole-organ deceased donor liver grafts between 1990 and 2009 who were followed up until September 2013.
Descriptive statistics were used to describe donor/recipient characteristics and transplant outcomes. Statistical comparisons between periods were performed using χ2/Fischer’s Exact test (categorical variables) and t-tests/Mann-Whitney U test (continuous variables). Univariate descriptive statistics/survival data were generated using Kaplan-Meier curves. Cox Proportional Hazards models were used for regression analyses of patient and graft survival.
Mean age (years), body mass index (BMI) (kg/m2), and proportion males were, respectively, 39.1 (± 17.4), 25.9 (± 5.7) and 60.3 for donors, and 51.3 (± 10.5), 27.7 (± 5.6), and 64.4 for recipients. Donor and transplantation rates differed between racial/ethnic groups. Overall survival at 1, 3, 5, 10, 15, and 20 years was 87.3%, 79.4%, 73.6%, 59.8%, 46.7%, and 35.9%, respectively. The 2005-2009 cohort had better patient and graft survival than the 1990-1994 cohort overall [HR 0.67 (0.62-0.72) and 0.66 (0.62-0.71)] and at five years [HR 0.73 (0.66-0.80) and 0.71 (0.65-0.77)].
The key findings were that despite changes in donor quality, recipient characteristics, and declining functional status among transplant recipients, overall patient survival is superior and post-transplant outcomes continue to improve. The long duration that this study encompassed involving the entire United States transplant institutions data has not been previously evaluated.
This is the first study to show that over time, despite transplanting high-risk recipients and utilizing high-risk deceased donors, transplant outcomes are getting better with the accumulation of experience. Future studies involving more specified liver transplant groups (such as transplant for hepatitis vs non-alcoholic steatohepatitis vs Laennec cirrhosis) would give insight into long-term outcomes within the category of end-stage liver disease.