Physical activity decreases in patients on the liver transplant waiting list and influences postoperative outcome-a prospective cohort study

Background: Physical deconditioning affects patients suffering from end-stage liver disease (ESLD). Liver transplantation (LT) is the only curative option for ESLD. Growing evidence suggests that pre-habilitation is beneficial in reducing post-surgical morbidity and mortality. We investigated physical activity (PA) in patients awaiting LT in a country with long waiting times. Methods: Prospective, single center, longitudinal study in Bern, Switzerland between June 2019 and February 2020 (halted due to SARS-CoV-2 pandemic), with follow-up data up to six months post-transplant. Patients were instructed to use a wrist tracker (FitBit) to monitor PA, which was assessed using mixed-effects generalized linear models. The study was approved by the local ethics committee (BASEC ID 2019-00606). Results: Thirty-five patients were included [71% male, median 59 years, body mass index (BMI) 28 kg/m(2), lab Model End-Stage Liver Disease (MELD) 11], 17 (49%) pre-frail and 5 (14%) frail according to the Liver Frailty Index (LFI). Twenty-eight patients underwent transplantation with 0 ninety-day mortality and 15 (53.6%) composite adverse clinical outcome. Median daily steps were 4,661 [interquartile range (IQR), 1,685-8,609] and weekly moderate PA (MPA) was 41 min (IQR, 0-127 min). Longitudinal analysis showed that female patients and patients on nutritional support had an increase in MPA between weeks 20 and 40. A significant decrease was seen in MPA after week 40, whilst no significant association was seen with age, Child-Pugh Score, LFI or quality of life at time of inclusion. MPA was significantly associated with the occurrence of the composite clinical endpoint after week 30 of waiting time (odds ratio 0.882, P=0.026). World Health Organization (WHO)-recommended MPA was significantly associated with less adverse composite clinical outcomes (P<0.001). Conclusions: In patients listed for LT, MPA decreased over time, showing a significant association with adverse outcome, specifically after week 30 on the waiting list. Our data support the implementation of routine pre-habilitation in patients awaiting LT.