Sarcopenia in Children with Liver Disease: A Pilot Study

ABSTRACT

Background and Aims Sarcopenia can be defined as loss of muscle mass, strength and function and has been shown to be associated with increased morbidity and mortality in the adult population. Sarcopenia has been assessed by decreased psoas muscle surface area (PMSA) on Computer tomography (CT) and has been validated in paediatric studies. The impact of Sarcopenia in children with end stage liver disease and oncological conditions is now being recognised. There is scarce literature on the effect of sarcopenia on motor function. CT imaging exposes children to radiation and hence is done in a select group of children at the time of transplant assessment. The aim of this audit was to assess the prevalence of Sarcopenia in children undergoing liver transplant assessment and its relationship on laboratory variables, functional activity and clinical outcomes. Methods Retrospective single centre case review of patients with liver disease undergoing transplant assessment and CT imaging between 2018-2020. Psoas muscle was analysed at the level of L4/L5. The z-Scores were calculated using ageand gender-specific reference values. Sarcopenia was defined as tPMA z score less than -2. We assessed the relationship of Sarcopenia to the biochemical parameters, nutritional status, effect on motor delay/physical abilities (assessed by a range of age appropriate standardised developmental and physical assessments due to COVID pandemic isolation restrictions) and post-transplant complications. Results Thirty one children that met the inclusion criteria were included. Sarcopenia was prevalent in 17 children (6 males 11 females), with a median age of 3.5 years (SD = 4.9). The common conditions were biliary atresia (n= 11, 35%), hepatoblastoma (n=6, 19%), Autoimmune hepatitis (n=3) etc. Twenty- four patients required additional nutritional support (77% nasogastric feeding, 13% PN and 6% oral supplementation). Mean tPMA z-score was -2.27. Data for the assessment of physical abilities/functional activity was available in 21 children. Impairment of motor skills/physical abilities was overall noted in 14/21 children (67%);9/13 (69%) in the sarcopenic group (6 significant impairment) vs 5/8 (63%) in non sarcopenic group (4 significant impairment). Sarcopenia was associated with increased complications (27 vs 7, p = 0.005) and hypoalbuminaemia (p=0.01), but was not statistically significant (p> 0.05) for the overall length of stay (total and intensive care). Discussion Sarcopenia was commonly identified in children with liver diseases undergoing transplant assessment. Reduction in physical abilities/functional activity was observed in both groups which may be a consequence of loss of muscle mass in children secondary to liver diseases or underlying oncological conditions leading to delay in gross motor skills. Although there was no statistical difference in the duration of stay or impairment of motor skills, complications were higher in the sarcopenic group. Conclusion In this pilot study, sarcopenia is prevalent in children being assessed for liver transplantation and was associated with increased complications. Better non-invasive methods (aside from CT scan) of assessing sarcopenia needs to be developed and validated for the paediatric age group, which would help to better characterise the true incidence and prevalence of sarcopenia in children with chronic liver disease. There is a need to offer nutritional support and assess physical function early in the pre transplant period in order to initiate appropriate physiotherapy interventions to halt and even reverse the progression of sarcopenia.