Systematic Reviews
Copyright ©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Hepatol. Oct 27, 2023; 15(10): 1153-1163
Published online Oct 27, 2023. doi: 10.4254/wjh.v15.i10.1153
Exercise training as an intervention for frailty in cirrhotic patients on the liver transplant waiting list: A systematic review
Thais Mellato Loschi, Melline D T A Baccan, Bianca Della Guardia, Paulo N Martins, Amanda P C S Boteon, Yuri L Boteon
Thais Mellato Loschi, Melline D T A Baccan, Bianca Della Guardia, Amanda P C S Boteon, Yuri L Boteon, Transplant Centre, Hospital Israelita Albert Einstein, São Paulo 05652-900, Brazil
Thais Mellato Loschi, Yuri L Boteon, Instituto Israelita de Ensino e Pesquisa Albert Einstein, Faculdade Israelita de Ciências da Saúde Albert Einstein, São Paulo 05652-900, Brazil
Paulo N Martins, Department of Surgery, Transplant Division, University of Massachusetts Medical School, Worcester, MA 01655, United States
Author contributions: Loschi TM and Boteon YL designed this study and drafted the manuscript; Loschi TM and Baccan MDTA performed the literature review and analysis; Loschi TM, Baccan MDTA, Della Guardia B, Martins PN, Boteon APCS, Boteon YL reviewed the manuscript critically; and all authors contributed to editing and approved the final manuscript version.
Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article.
PRISMA 2009 Checklist statement: The authors have read the PRISMA 2009 Checklist, and the manuscript was prepared and revised according to the PRISMA 2009 Checklist.
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: Yuri L Boteon, FACS, MD, PhD, Doctor, Professor, Surgeon, Transplant Centre, Hospital Israelita Albert Einstein, 2nd Floor, Building A1, Office 200B, 627/701 Albert Einstein Avenue, São Paulo 05652-900, Brazil. yuri.boteon@einstein.br
Received: August 25, 2023
Peer-review started: August 25, 2023
First decision: September 15, 2023
Revised: September 21, 2023
Accepted: October 8, 2023
Article in press: October 8, 2023
Published online: October 27, 2023
Processing time: 59 Days and 13.3 Hours
Abstract
BACKGROUND

The existing literature suggests that exercise for cirrhotic patients is safe and favours significant improvement to their physical capacity. However, exercise training for this population and how to deliver activities, especially in severe stages of the disease and while waiting for a liver transplant (LT), remain undefined.

AIM

To review the existing exercise prescriptions for cirrhotic patients on the waiting list for LT, their results for frailty evolution and their effect on clinical outcomes.

METHODS

A systematic review was performed following the Preferred Reporting Review and Meta-Analysis guidelines and searching the PubMed, MEDLINE, and Scopus databases. The keyword “liver transplant” was used in combination with the free terms “frailty” and “exercise” for the literature review. Clinical studies that evaluated the effect of a regular training program, independent of supervision or the duration or intensity of physical exercise, in cirrhotic patients on the waiting list for LT were reviewed. The data on safe physical activity prescriptions following Frequency, Intensity, Time, and Type recommendations were extracted and summarised.

RESULTS

Nine articles met the inclusion criteria for this review. Various instruments for frailty assessment were used, frequently in combination. Five studies prescribed physical activity for patients, one in-person and four to be performed remotely and unsupervised. The remaining four studies only used a self-report instrument to assess the level of physical activity. None reported adverse events related to exercise training. The exercise frequency mainly varied from daily to a minimum of twice per week. The intensity depended on frailty and included increasing levels of activity. The type of exercise was predominantly a combination of aerobic and resistance training. The duration of exercise varied from 4 to 12 wk. Three articles evaluated the effect of the exercise program on clinical outcomes, reporting a reduction in 90-d readmission rates post-transplant and improved frailty scores, as well as improved survival of cirrhotic patients waiting for LT.

CONCLUSION

Routine frailty assessment is essential for this population. Although more robust evidence is required, the prescription of exercise is safe and can improve patients’ functional capacity, improving pre- and post-LT outcomes.

Keywords: End-stage liver disease, Liver transplant, Frailty, Exercise, Rehabilitation, Sarcopenia

Core Tip: Frailty negatively affects the outcomes of patients waiting for liver transplants (LTs). However, the tools used to assess frailty and functional performance vary amongst the existing studies, limiting the estimation of the real and accurate prevalence of the condition and the effectiveness of proposed treatments. So far, existing studies suggest that exercise may improve cirrhotic patients’ functional capacity and frailty while they are on the waiting list for LTs. In addition, although evidence is scarce, studies affirm that exercise training improves pre- and post-LT outcomes.