Retrospective Cohort Study
Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Transplantation. Sep 10, 2018; 8(5): 167-177
Published online Sep 10, 2018. doi: 10.5500/wjt.v8.i5.167
Trends of characteristics and outcomes of donors and recipients of deceased donor liver transplantation in the United States: 1990 to 2013
Subhashini Ayloo, Sri Ram Pentakota, Michele Molinari
Subhashini Ayloo, Sri Ram Pentakota, Department of Surgery, Rutgers New Jersey Medical School, Newark, NJ 07103, United States
Michele Molinari, Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA 15213, United States
Author contributions: Ayloo S contributed to this paper with conception, design, analysis, and manuscript drafting; Pentakota SR contributed to data analysis; Molinari M contributed to data analysis and manuscript drafting.
Institutional review board statement: The study did not require approval by the ethics review board of our institution because it was conducted and reported per STROBE statement recommendations which was acknowledged in the methods section of the manuscript. This data is available to everybody and is provided by OPTN/UNOS as SRTR files.
Informed consent statement: Not applicable.
Conflict-of-interest statement: All authors report no conflict of interest.
STROBE statement: The study was reported in accordance with STROBE statement.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Subhashini Ayloo, MD, Associate Professor, Senior Scientist, Statistician, Surgeon, Department of Surgery, Rutgers New Jersey Medical School, 185 South Orange Avenue, MSB G586, Newark, NJ 07103, United States. ayloo.sub@rutgers.edu
Telephone: +1-973-9725874 Fax: +1-973-9723135
Received: April 6, 2018
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
ARTICLE HIGHLIGHTS
Research background

The long-term impacts of clinical advancements and policy interventions over the past two decades on liver transplant outcomes have been poorly studied.

Research motivation

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.

Research objectives

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.

Research methods

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.

Research results

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)].

Research conclusions

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.

Research perspectives

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.