Retrospective Cohort Study
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World J Gastrointest Surg. Feb 27, 2024; 16(2): 331-344
Published online Feb 27, 2024. doi: 10.4240/wjgs.v16.i2.331
Influence of donor age on liver transplantation outcomes: A multivariate analysis and comparative study
Miran Bezjak, Ivan Stresec, Branislav Kocman, Stipislav Jadrijević, Tajana Filipec Kanizaj, Miro Antonijević, Bojana Dalbelo Bašić, Danko Mikulić
Miran Bezjak, Branislav Kocman, Stipislav Jadrijević, Danko Mikulić, Department of Surgery, University Hospital Merkur, Zagreb 10000, Croatia
Ivan Stresec, Bojana Dalbelo Bašić, Department of Electronics, Microelectronics, Computer and Intelligent Systems, Faculty of Electrical Engineering and Computing, Zagreb 10000, Croatia
Tajana Filipec Kanizaj, Department of Gastroenterology, University Hospital Merkur, Zagreb 10000, Croatia
Miro Antonijević, Development of Software, Nanobit Ltd., Zagreb 10000, Croatia
Author contributions: Bezjak M, Stresec I, and Mikulić D designed the study and contributed to data collection, drafting, and revising the manuscript; Kocman B, Jadrijević S, and Filipec Kanizaj T participated in data collection and they critically reviewed the manuscript; Stresec I, Antonijević M, and Dalbelo Bašić B contributed to the data analysis; all authors read and approved the final version of the manuscript.
Supported by the European Regional Development Fund (DATACROSS), No. KK.01.1.1.01.0009.
Institutional review board statement: This study was reviewed and approved by the Ethics Committee of the University Hospital Merkur, Zagreb (No. 03/1-2180).
Informed consent statement: All patients signed a general informed consent agreeing to the treatment and use of their anonymised clinical data.
Conflict-of-interest statement: All authors have nothing to disclose.
Data sharing statement: The statistical code and dataset associated with this research are available from the corresponding author upon request at [mikulicdanko@gmail.com] for researchers who provide a methodologically sound proposal. To gain access, data requestors will need to sign a non-disclosure agreement (NDA). All data have been anonymized, and the risk of identification is minimized. We may balance the potential benefits and risks for each request and then provide the data that could be shared.
STROBE statement: The authors have read the STROBE Statement—checklist of items, and the manuscript was prepared and revised according to the STROBE Statement—checklist of items.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (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: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Danko Mikulić, FEBS, MD, PhD, Surgeon, Department of Surgery, University Hospital Merkur, Department of Surgery, University Hospital Merkur, 10000 Zagreb, Croatia. mikulicdanko@gmail.com
Received: October 9, 2023
Peer-review started: October 9, 2023
First decision: December 8, 2023
Revised: December 18, 2023
Accepted: January 29, 2024
Article in press: January 29, 2024
Published online: February 27, 2024
Processing time: 138 Days and 21.3 Hours
ARTICLE HIGHLIGHTS
Research background

Liver transplantation (LT) is a vital treatment for end-stage liver diseases, but the demand for donor organs far exceeds their availability. The utilization of older liver grafts has emerged as a potential solution, challenging the historical perception of inferior outcomes associated with elderly donors. Traditionally, concerns regarding increased graft loss and complications have limited the use of older liver grafts. Our study, conducted at the University Hospital Merkur, Zagreb, reevaluates the impact of donor age on LT outcomes. By employing multivariate analysis and a comparative approach, we aim to provide a nuanced understanding of the relationship between donor age, patient survival, and graft viability. Our investigation goes beyond binary comparisons, treating donor age as a continuous variable and considering additional risk factors. The outcomes of this research have the potential to inform organ allocation strategies, refine donor selection criteria, and contribute to the broader discourse on optimizing LT programs.

Research motivation

Our study is motivated by the pressing challenges in LT, where the demand for donor organs exceeds their availability. This research seeks to optimize organ allocation strategies and reshape the perception of elderly liver grafts. Solving these challenges holds significance beyond immediate organ scarcity concerns, influencing future studies to redefine donor selection criteria and foster a more inclusive and efficient LT paradigm. This motivation aligns with the broader goal of optimizing LT programs, encouraging further exploration of alternative strategies to meet the growing demand for life-saving transplants.

Research objectives

Our focus is on a detailed evaluation of how donor age influences LT outcomes. We aim to conduct a meticulous multivariate analysis on 656 liver transplants, treating donor age as a continuous variable. Our objectives include assessing statistical significance, exploring transformations and interactions, and conducting a comparative analysis between elderly and young donor liver grafts. The significance of realizing these objectives extends to future research in the field. By challenging conventional beliefs and providing evidence-based insights, our study contributes to refining organ allocation strategies and donor selection criteria. The outcomes of our study will encourage future research in other centers with the overall goal of optimizing the LT programs.

Research methods

We analyzed a dataset of 656 liver transplants from 2013 to 2018. Our approach involved advanced statistical modeling, treating donor age as a continuous variable. This allowed us to assess its significance from several perspectives through different multivariate models. Additionally, to exemplify the similarity of using young and old donor liver grafts we conducted a comparative analysis between elderly and young donor groups. This methodology combines various statistical techniques to uncover the nuanced dynamics of donor age impact.

Research results

Through meticulous analysis, we discovered that donor age does not exert a significant impact on patient survival. The multivariate Cox analysis consistently showed its insignificance, even when considering potential transformations and interactions. These results contribute valuable insights to the field, indicating that elderly liver grafts perform comparably to younger grafts when accounting for other risk factors. The study highlights the importance of factors beyond donor age in shaping transplantation outcomes. While our findings provide clarity on this aspect, challenges remain in further refining organ allocation strategies. Our results, therefore, not only contribute to the current body of research but also set the stage for addressing future challenges in LT.

Research conclusions

This study challenges existing paradigms by asserting that donor age is not a significant factor in LT outcomes. Our findings suggest a shift from conventional beliefs, emphasizing that elderly liver grafts perform similarly to their younger counterparts when considering additional risk factors. The study's contribution lies in debunking age-centric theories and fostering a more nuanced understanding of the factors influencing transplant success. While not introducing entirely new methods, our approach combines various statistical techniques in a novel way, providing a comprehensive assessment of donor age impact. The conclusions emphasize the need to reconsider the significance of donor age and advocate for a more holistic approach in shaping LT practices.

Research perspectives

Future research in this field should delve into refining organ allocation strategies, considering factors beyond donor age. The study's insights open avenues for exploring the impact of additional risk factors on transplantation outcomes. Further investigations could focus on optimizing matching criteria and identifying novel predictors for success in LT. As the landscape of LT evolves, future research should continue to challenge traditional beliefs and seek innovative approaches for enhancing overall transplant success.