Retrospective Cohort Study
Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Nov 21, 2018; 24(43): 4920-4927
Published online Nov 21, 2018. doi: 10.3748/wjg.v24.i43.4920
Warm ischemia time and elevated serum uric acid are associated with metabolic syndrome after liver transplantation with donation after cardiac death
Liang-Shuo Hu, Yi-Chao Chai, Jie Zheng, Jian-Hua Shi, Chun Zhang, Min Tian, Yi Lv, Bo Wang, Ai Jia
Liang-Shuo Hu, Yi-Chao Chai, Jian-Hua Shi, Chun Zhang, Min Tian, Yi Lv, Bo Wang, Department of Hepatobiliary Surgery, First Affiliated Hospital of Xi’an Jiaotong University, Xi’an 710061, Shaanxi Province, China
Jie Zheng, Clinical Research Center, First Affiliated Hospital of Xi’an Jiaotong University, Xi’an 710061, Shaanxi Province, China
Ai Jia, Department of Gastroenterology, First Affiliated Hospital of Xi’an Jiaotong University, Xi’an 710061, Shaanxi Province, China
Author contributions: Hu LS and Chai YC contribute equally to this work. This clinical research was conceived and designed by Jia A and Wang B, who acted co-corresponding authors. The data was collected by Shi JH, Zhang C, and Tian M. Zheng J provided statistical analysis. Interpretation of the data was performed by Hu LS and Chai YC, who also wrote the paper. Critical revision of the article was executed by Lv Y, Wang B, and Jia A. All authors participated in the revision of the manuscript. All authors read and approved the final manuscript.
Supported by the National Natural Science Foundation, No. 81270521 (to Wang B.
Institutional review board statement: The clinical trial of this paper was reviewed and approved by the Committee of Medical Ethics of First Affiliated Hospital of Xi’an Jiaotong University (No. XJTU1AF2018LSK-084).
Informed consent statement: The form of consent to data acquisition was signed by patients or their guardian.
Conflict-of-interest statement: The authors report no conflicts of interest in this work.
Data sharing statement: All datasets used and/or analyzed during the current study are available from the corresponding author upon reasonable request.
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 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:
Correspondence to: Ai Jia, MD, Research Associate, Internist, Department of Gastroenterology, First Affiliated Hospital of Xi’an Jiaotong University, No. 277, West Yanta Road, Xi’an 710061, Shaanxi Province, China.
Telephone: +86-29-85323927 Fax: +86-29-85323902
Received: September 3, 2018
Peer-review started: September 3, 2018
First decision: October 8, 2018
Revised: October 15, 2018
Accepted: November 8, 2018
Article in press: November 8, 2018
Published online: November 21, 2018
Research background

Liver transplantation (LT) is still the standard treatment for patients with end-stage liver disease. The usage of livers from donation after cardiac death (DCD) donors has increased rapidly. Current research shows that some risks of a series of acute and chronic complications are correlated with the warm ischemia time (WIT). Thus, the long-term prognosis of DCD LT has gained increasing attention.

Research motivation

After LT, patients may develop a series of metabolic disorders which is called posttransplant metabolic syndrome (PTMS). However, data on specific assessment of the morbidity of PTMS after DCD LT are still lacking. Therefore, this study aimed to further explore the prevalence of PTMS after DCD LT and the pre- and postoperative risk factors, to provide evidence for clinical decision rules.

Research objectives

The present retrospective analysis describes the prevalence of PTMS after DCD LT and the pre- and postoperative risk factors that are relevant to the occurrence of PTMS, and provides evidence for clinical judgment.

Research methods

This is a retrospective cohort study. One hundred and forty-seven subjects who underwent DCD liver transplantation from January 2012 to February 2016 were enrolled in this study. The pre- and post-transplantation demographics and clinical characteristics were collected for both recipients and donors. All subjects were followed monthly for the initial 6 mo after discharge, and then, every 3 mo for 2 years. The subjects were followed every 6 mo or as required after 2 years post-LT. All data were used to perform statistical analysis and identify the variables independently associated with PTMS in the final multivariate model.

Research results

In this retrospective cohort study, the prevalence of PTMS after DCD donor orthotopic LT was 13.6%. Recipient’s body mass index, WIT, and posttransplant hyperuricemia were significantly associated with PTMS. The change in serum uric acid level in PTMS patients was significantly higher than that in non-PTMS patients. After the 1st month, the level of serum uric acid of PTMS patients rose continually over a period, while it was unaltered in non-PTMS patients. After transplantation, the level of serum uric acid in PTMS patients was not associated with renal function.

Research conclusions

PTMS could occur at early stage after LT DCD with growing morbidity as time goes on. For the first time, we found that prolonged WIT and the posttransplant hyperuricemia were associated with the prevalence of PTMS, and an increased serum uric acid level was highly associated with PTMS and could serve as a serum marker for monitoring such a disease.

Research perspectives

In this study, the ineluctable WIT rather than cold ischemia time for DCD LT was found initially as an independent risk factor of PTMS. Nonetheless, further experiments are essential for exploring the underlying mechanism. Our data also indicated that the increased serum uric acid level was highly associated with PTMS. Although prolonged WIT remains a potential cause for the tendency of a rapid rise in the level of serum uric acid in the perioperative period of LT, after a sharp increase in the first month, the level of uric acid stabilized in the non-PTMS cohort. However, it continued to increase in PTMS patients and overstepped the upper limit of normal blood uric acid concentration. Intriguingly, after adjusting for renal function, the disparity in the values persisted. Recently, accumulating evidence also suggests the standpoint that uric acid is an independent predictor of metabolic syndrome. In consideration of our research results, more prospective studies are urgently required to provide evidence for clinical verification. Future research should include larger cohorts of patients from multiple centers to expand the sample size and establish a more comprehensive long-term follow-up to improve the statistical database containing more factors, including PTMS and survival rate.