Improving the prognosis before and after liver transplantation: Is muscle a game changer?

Table 1 Main studies investigating the deleterious role of frailty, low muscle mass, sarcopenia and myosteatosis in patients undergoing pre-transplant assessment

Ref.	Patient selection	Patients, n	Sarcopenia, myosteatosis	Frailty parameters	Outcome	Results
Lai et al[15], 2019	Ambulatory cirrhotic patients awaiting LT	1014	Non applicable	LFI	Waiting list mortality	Frailty: 25%. HR = 1.82; 95%CI: 1.31-2.52; P < 0.001
Fozouni et al[48], 2020	LT recipients	241	Non applicable	LFI	Acute cellular rejection within 3 mo post-LT	Frailty: 19%. OR = 3.3; 95%CI: 1.2-9.3; P = 0.02
Lai et al[47], 2022	LT recipients	1166	Non applicable	LFI	LT LOS. ICU stay. Inpatient days within 3 mo post-LT. Overall survival (1-3 and 5-yr mortality)	Frailty: 21%. Prolonged LT LOS: OR = 2.00; 95%CI: 1.47-2.73. ICU stay: OR = 1.56; 95%CI: 1.12-2.14. Inpatient days within 3 mo. post-LT: OR = 1.72; 95%CI: 1.25-2.37. Overall survival: P = 0.02
Bhanji et al[41], 2018	Cirrhotic patients assessed for LT	675	L3-MA (HU). L3-SMI	Non applicable	HE. Mortality	Sarcopenia: 36%. HE: OR = 2.42; 95%CI: 1.43-4.10; P = 0.001. Mortality: Univariate HR = 2.02; 95%CI: 1.57-2.58; P < 0.001. Multivariate: HR = 2.15; 95%CI: 1.52-3.05; P < 0.001. Myosteatosis: 52%. HE: OR = 2.25; 95%CI: 1.32-3.85; P = 0.003. Mortality: Univariate: HR = 1.45; P = 0.004; 95%CI: 1.16-2.91. Multivariate: P = 0.69
Van Vugt et al[42], 2016	LT candidates/recipients	3804. Meta-analysis	SMI. Total psoas area	Non applicable	Waiting list mortality. Post-LT mortality	Waiting list mortality: HR = 1.72; 95%CI: 0.99-3.00; P = 0.02. Post-LT mortality: HR = 1.84; 95%CI: 1.11-3.05; P = 0.05
Bot et al[40], 2021	ESLD patients awaiting LT	262	L3-SMI (cm2/m2). L3-MA (HU)	Non applicable	Waiting list mortality	Low SMI: HR = 2.580; 95%CI: 1.055-6.308. MA: HR = 9.124; 95%CI: 2.871-28.970
Czigany et al[24], 2020	LT recipients	225	L3-SMI. L3-MA (HU)	Non applicable	Major morbidity. ICU stay. LT LOS	Sarcopenia: 37%. Myosteatosis: 44%. Major morbidity: OR = 2.772; 95%CI: 1.516-5.066; P = 0.001. ICU stay: 18 ± 25 vs 11 ± 21 d, P < 0.001. LT LOS: 56 ± 55 vs 33 ± 24 d, P < 0.001

LFI: Liver frailty index; HR: Hazard ratio; CI: Confidence interval; LT: Liver transplantation; OR: Odds ratio; LT LOS: Liver transplantation length of stay; ICU: Intensive care unit; L3-MA: Lumbar 3-muscle attenuation; HU: Hounsfield unit; L3-SMI: Lumbar 3-skeletal muscle index; HE: Hepatic encephalopathy; SMI: Skeletal muscle index; ESLD: End stage liver disease.