Abstract

Background: Physical frailty and sarcopenia are related but not fully overlapping, and links to outcomes and health care utilization in liver cirrhosis. Physical frailty may be assessed with Liver Frailty Index (LFI) or Short Performance Physical Battery (SPPB), and sarcopenia is typically assessed by measuring muscle size using imaging.

A magnetic resonance imaging (MRI) based assessment (Muscle Assessment Score [MAsS]) combining sex-adjusted thigh muscle fat infiltration (MFI) and muscle volume z-score (MVZ), has been developed to describe muscle health. Large population studies have shown that MAsS better predicts physical function and hospitalization than its individual components. MAsS can be used to detect muscle composition (MC) phenotypes, of which adverse MC (high MFI & low MVZ) independently predicts all-cause mortality.

The aim was to assess the association of MAsS and L3 skeletal muscle index (L3-SMI) with physical frailty tests (SPPB & LFI) and assess MC phenotypes in ACCESS-ESLD – a prospective longitudinal multi-center cohort study of patients with liver cirrhosis.

Methods: MAsS and L3-SMI were measured using AMRA® Researcher based on an 8 min MRI acquired on the same day as SPPB and LFI. SPPB was grouped as very low-to-low (<7), moderate (7-9), and high (10-12) physical performance. LFI was grouped as frail (>4.5), prefrail (3.8-4.4), less robust (3.2-3.7), and robust (<3.2). MC phenotypes were defined according to literature. T-tests were used for statistical testing.

Results: The first 76 patients (46 males; BMI 29.5 ± 6.3 kg/m²; Age 66 ± 10 yrs; mainly alcohol related cirrhosis and NAFLD, but also hepatitis B and C, and autoimmune diseases) were included.

Patients with moderate (compared to high) physical performance had increased MFI from baseline (+1.77 pp, p=0.020). There was no difference in MVZ nor L3-SMI. Only 3 patients had very low-to-low physical performance.

MFI was higher in frail (+3.70 pp, p=0.035) and prefrail (+1.16 pp, p=0.040) compared to robust, and in frail (+2.98 pp, p=0.035) compared to less robust. MVZ was lower in prefrail (-0.72 SD, p=0.049) and less robust (-0.86 SD, p=0.029) compared to robust. There was no difference for L3-SMI.

Patients with adverse MC (n=15) had higher LFI (3.98 v 3.49, p=0.040), lower SPPB (8.93 v 10.26, p=0.020), and lower L3-SMI (42.5 v 49.3, p=0.035) compared to all other MC phenotypes (see MC prevalences in Fig) without differences in BMI or age.

Conclusion: Results suggest that 20% of patients with cirrhosis have adverse MC, a large group (53%) low muscle volume, and few (5%) only high fat (see Fig). MFI was significantly higher with reduced physical function and by increasing frailty index. Adverse MC, as detected by MAsS, showed significantly higher frailty and lower physical performance, unrelated to age and BMI. These results indicates that MFI could be used as a frailty marker and that MAsS describes both frailty and sarcopenia in patients with liver cirrhosis.