Impact of COVID-19 on Liver Transplantation on Hong Kong and Singapore: A Modelling Study with Forecasts Till 2025

Abstract

Background: Liver transplantation (LT) activities during the COVID-19 pandemic have been curtailed in many countries. However, the impact of various policies restricting LT on outcomes of patients on the LT waitlist is unclear.Methods: We studied all patients on the nationwide LT waitlists in Hong Kong and Singapore between January 2016 and May 2020. We used a continuous time Markov chains to model the effects of various scenarios on waitlisted patients and then projected the effect of varying durations of LT disruption on outcomes.Findings: With complete cessation of LT, the projected 1-year overall survival (OS) decreased by 3·6%, 10·51% and 19·21% for a 1-, 3- and 6- month disruption respectively versus no limitation to LT, while 5-year OS decreased by 5·3%, 15·81%, and 31·11% respectively. When only urgent (acute-on-chronic liver failure [ACLF] or acute liver failure) LT was allowed, the projected 1-year overall survival (OS) decreased by a similar proportion: 3·1%, 8·41% and 15·20% respectively. When DDLT and urgent LDLT were allowed, 1-year projected OS decreased by 1·2%, 5·1% and 8·85% for a 1-, 3- and 6-month disruption respectively, with similar OS when only DDLT was allowed. Complete cessation of LT activities resulted in an increased projected incidence of ACLF at 1-year by 17·6%, 49·1% and 95·5% for a 1-, 3- and 6- month disruption, as well as an increase in hepatocellular carcinoma (HCC) dropout resulting in delisting at 1-year by 31·8%, 107·96% and 176·06% respectively. When only urgent LT was allowed, HCC dropout and ACLF incidence were similar to the scenario with complete cessation of LT.Interpretation: A short and intensive disruption to LT results in better survival compared with a longer duration of partial restrictions. Disruption to LT activities results in a substantial increase in the proportion of HCC dropouts.Funding Statement: No external funding to disclose.Declaration of Interests: DQH: Research support: Exxon Mobil-NUS Research Fellowship for Clinicians, NMRC Research Training Fellowship; Advisory Board: Eisai. All other authors have nothing to discloseEthics Approval Statement: This study was approved by the Domain Specific Review Board (2020/01129) of National Healthcare Group, Singapore.