Post-liver transplantation sarcopenia in cirrhosis: a prospective evaluation

The adverse impact of perioperative body composition abnormalities on outcomes after split liver transplantation: a multicenter retrospective cohort study

BACKGROUND

Split liver transplantation (SLT) increases graft availability, but it's safe and effective utilization is insufficiently documented. This study aimed to investigate the association between perioperative body composition abnormalities and outcomes in adult SLT.

MATERIALS AND METHODS

Two hundred forty recipients who underwent SLT in three centers were enrolled in this retrospective cohort study. Body composition abnormalities including sarcopenia, myosteatosis, visceral obesity, and sarcopenic obesity were evaluated at baseline and 1 month after surgery using computed tomography. Their impact on outcomes including early allograft dysfunction, early complications, ICU stay, graft regeneration rate, and survival was analyzed.

RESULTS

Recipients with sarcopenia or myosteatosis had a higher risk of early allograft dysfunction, higher early complication rate, and longer length of ICU stay (all P <0.05), while there was no difference in graft regeneration rate. Recipient and graft survival were significantly worse for recipients with body composition abnormalities (all P <0.05). In multivariable Cox-regression analysis, sarcopenia [hazard ratio (HR)=1.765, P =0.015], myosteatosis (HR=2.066, P =0.002), and visceral obesity (HR=1.863, P =0.008) were independently associated with shorter overall survival. Piling up of the three factors increased the mortality risk stepwise ( P <0.001). Recipients experienced skeletal muscle loss and muscle fat infiltration 1 month after surgery. Postoperative worsening sarcopenia (HR=2.359, P =0.009) and myosteatosis (HR=1.878, P =0.026) were also identified as independent risk factors for mortality.

CONCLUSION

Sarcopenia, myosteatosis, and their progression negatively affect outcomes including early allograft dysfunction, early complications, ICU stay and survival after SLT. Systemic evaluation and dynamic monitoring of body composition are valuable.

Correlation between sarcopenia and cirrhosis: a meta-analysis

Background

The relationship between sarcopenia and cirrhosis is unclear. In this research, our aim is to evaluate the prevalence of sarcopenia among individuals with liver cirrhosis and its correlation with survival and mortality risks.

Methods

We conducted searches on PubMed, Web of Science, EMBASE, and Cochrane for English articles published up to July 10, 2023, and additionally manually searched the bibliography of relevant articles. We incorporated research on sarcopenia in patients with cirrhosis to examine the connection between sarcopenia and the likelihood of survival and mortality. Statistical analyses were carried out utilizing the Stata version 15.1 software. Depending on the heterogeneity of the results, we employed either fixed-effects models or random-effects models for data synthesis. To assess publication bias, we employed funnel plots and conducted Egger's test.

Results

We included 40 studies involving 8,945 patients with cirrhosis. The overall prevalence of cirrhosis was 41% (95% CI 34%-48%). Male patients and those with liver cirrhosis and hepatic encephalopathy had a higher prevalence of sarcopenia (44% for male patients and 48% for hepatic encephalopathy patients). Sarcopenia emerged as a risk factor for both survival (HR = 2.57, 95% CI 2.02-3.27, p < 0.001) and mortality (HR = 2.13, 95% CI 1.86-2.44, p < 0.001) in patients with cirrhosis. Subgroup analyses consistently yielded the same results for study sites, whether HCC patients were excluded from the cohort, whether patients were from the liver transplant cohort or had undergone tips surgery, the definition of sarcopenia (L3-SMI or other methods), and the diagnostic criteria used by patients. The presence of sarcopenia was also a significant risk factor for hepatic encephalopathy [HR = 2.27, 95% CI (1.76-2.94), p < 0.001].

Conclusion

This systematic review and meta-analysis reveal that patients with cirrhosis have a prevalence of sarcopenia of 41% and is associated with survival rate and mortality rate. Therefore, we should attach importance to the screening of sarcopenia in patients with cirrhosis, early detection of susceptible populations, and appropriate measures to reduce the occurrence and adverse outcomes.Systematic review registration:https://www.crd.york.ac.uk/PROSPERO/#recordDetails.

Impact of Liver Transplantation on Adipose Tissue Compartments and Its Association With Metabolic Sequela

BACKGROUND

Loss of skeletal muscle can be accompanied by an increase in adipose tissue leading to sarcopenic obesity. There are limited data on how liver transplantation (LT) might impact adipose tissue compartments, particularly among patients with metabolically active disease, such as nonalcoholic steatohepatitis (NASH) and subsequent metabolic sequela.

METHODS

Skeletal muscle, visceral adipose tissue (VAT), and subcutaneous adipose tissue (SAT) were measured using cross-sectional imaging performed in 190 patients pre-LT, 6 mo post-LT and 12 mo post-LT. Changes in adipose tissue and their impact on metabolic diseases were determined in patients transplanted for NASH versus non-NASH.

RESULTS

Skeletal muscle, VAT, and SAT were similar in patients with NASH and non-NASH pre-LT despite a higher burden of metabolic diseases in patients with NASH. Following LT, no significant differences between skeletal muscle and SAT were observed in the entire cohort and among patients with NASH (versus non-NASH). LT recipients with the highest muscle mass pre-LT were at the greatest risk for muscle loss post-LT. A time-dependent increase in VAT was noted post-LT, which was more robust among patients with a history of NASH cirrhosis. In adjusted multivariate analysis, NASH versus non-NASH was a strong predictor of post-LT increase in VAT (β-coefficient 3.00, P  = 0.04). Pre-LT VAT was an independent predictor of post-LT serum triglycerides (β-coefficient 5.49 ± 2.78, P  = 0.05) and low-density lipoprotein cholesterol (β-coefficient 1.80 ± 0.75, P  = 0.02). A trend between pre-LT VAT and diabetes was noted but did not reach statistical significance.

CONCLUSIONS

VAT but not SAT increases rapidly after LT, especially among patients transplanted for NASH cirrhosis and predicts future metabolic burden.

Association of Muscle Mass Loss with Diabetes Development in Liver Transplantation Recipients

BACKGRUOUND

Post-transplant diabetes mellitus (PTDM) is one of the most significant complications after transplantation. Patients with end-stage liver diseases requiring transplantation are prone to sarcopenia, but the association between sarcopenia and PTDM remains to be elucidated. We aimed to investigate the effect of postoperative muscle mass loss on PTDM development.

METHODS

A total of 500 patients who underwent liver transplantation at a tertiary care hospital between 2005 and 2020 were included. Skeletal muscle area at the level of the L3-L5 vertebrae was measured using computed tomography scans performed before and 1 year after the transplantation. The associations between the change in the muscle area after the transplantation and the incidence of PTDM was investigated using a Cox proportional hazard model.

RESULTS

During the follow-up period (median, 4.9 years), PTDM occurred in 165 patients (33%). The muscle mass loss was greater in patients who developed PTDM than in those without PTDM. Muscle depletion significantly increased risk of developing PTDM after adjustment for other confounding factors (hazard ratio, 1.50; 95% confidence interval, 1.23 to 1.84; P=0.001). Of the 357 subjects who had muscle mass loss, 124 (34.7%) developed PTDM, whereas of the 143 patients in the muscle mass maintenance group, 41 (28.7%) developed PTDM. The cumulative incidence of PTDM was significantly higher in patients with muscle loss than in patients without muscle loss (P=0.034).

CONCLUSION

Muscle depletion after liver transplantation is associated with increased risk of PTDM development.

Impact of sarcopenia on the survival of patients undergoing liver transplantation for decompensated liver cirrhosis

BACKGROUND

Patients with decompensated cirrhosis (DC) are prone to skeletal muscle loss, namely, sarcopenia, before liver transplantation (LT). While sarcopenia is reportedly associated with adverse outcomes after LT, these findings are limited owing to mixed diseases and retrospective data. We investigated the association between sarcopenia and 1-year overall survival (OS) in patients with DC after LT and established and validated a prediction model for postoperative OS based on sarcopenia.

METHODS

Overall, 222 consecutive patients who underwent LT at our centre were registered between September 2020 and June 2022. Third lumbar spine skeletal muscle mass index was measured using computed tomography. Patients were divided into sarcopenia and non-sarcopenia groups according to the skeletal muscle mass index, and baseline data and postoperative outcomes were collected, compared and analysed. The primary outcome was the 1-year OS after LT. We established a dynamic nomogram of the OS predictive model.

RESULTS

We included 177 DC patients [mean (standard deviation) age, 50.2 ± 9.3 years; 52 women (29.4%)]; 73 (41.2%) had sarcopenia. The mean (standard deviation) body mass index was 22.6 ± 4.5 kg/m2 , 28 (15.8%) patients had weight loss ≥5% within 6 months before admission, and the mean (standard deviation) model for end-stage liver disease (MELD) score was 18.4 ± 7.9. Patients with sarcopenia had a longer duration of intensive care unit stay (4.1 ± 2.2 vs. 3.1 ± 1.1 days, P = 0.008), higher rate of major complications (45.2% vs. 22.1%, P = 0.001) and higher postoperative mortality (15.1% vs. 2.9%, P = 0.003) than those without sarcopenia. The median 1-year OS after surgery was shorter in patients with sarcopenia than in those without (P < 0.001). Sarcopenia [hazard ratio (HR), 2.54; 95% confidence interval (CI), 1.54-5.63; P = 0.022], weight loss ≥5% (HR, 2.46; 95% CI, 1.39-5.09; P = 0.015) and MELD score (HR, 1.05; 95% CI, 1.01-1.09; P = 0.009) were independent risk factors associated with 1-year OS. The area under the curve of the established dynamic nomogram was 0.774, the calibration curve showed good consistency, and analysis of the decision curve showed more clinical benefits than the MELD score alone. High-risk patients (>102.9 points calculated using the nomogram) had a significantly reduced survival rate.

CONCLUSIONS

Sarcopenia is associated with adverse outcomes after LT in patients with DC. High-risk patients should be classified by dynamic nomogram upon admission.

Cirrhosis-related sarcopenia may not resolve after liver transplantation

Background & Aims

Sarcopenia has significant burden in cirrhosis and has been shown to worsen short-term post-liver transplantation (LT). This study aims to evaluate the long-term change in sarcopenia post-LT along with its associations and predictors.

Methods

A retrospective study of adult patients who underwent LT at a tertiary centre between 1/1/2009 and 12/31/2018. Relevant demographic and clinical data were collected. Skeletal muscle index (SMI) was calculated using standard of care computerised tomography (CT) scans pre- and post-LT. Sarcopenia was defined using previously established cut-points. The primary outcome was SMI change post-LT and secondary outcome was post-LT mortality.

Results

Out of 1165 patients, 401 met inclusion criteria (1,205 CT scans reviewed). The average age at transplant was 57 years; 63% were male. The average BMI was 28 kg/m2. Thirteen percent of females and 32% of males had sarcopenia pre-LT. Post-LT SMI declined by 4.7 cm2/m2 in the first year then by 0.39 cm2/m2 per year thereafter. Females had greater rate of decline in SMI after the first year compared with males (0.87 cm2/m2 per year vs. 0.17 cm2/m2 per year, respectively, p = 0.02). Post-LT physical rehabilitation, infection, and readmissions were not associated with SMI trajectory. At 3 years post-LT, 31% of females and 48% of males had sarcopenia. Baseline sarcopenia was the only predictor of long-term post-LT sarcopenia on multivariable analysis, but it was not associated with mortality.

Conclusions

Sarcopenia does not appear to resolve post-LT and likely worsens leading to nearly doubling its prevalence in those with long-term follow-up. Immediate post-LT physical rehabilitation was not associated with SMI trajectory in our cohort.

Impact and implications

The prevalence of sarcopenia is high among patients with cirrhosis; however, data are mixed on the impact of sarcopenia on post-liver transplant (LT) course and there have been no studies evaluating the long-term evolution of sarcopenia post-LT beyond 1 year. In this study, we analysed changes in muscle mass up to 3 years after transplant in 401 patients and found that sarcopenia did not resolve in most liver transplant recipients and skeletal muscle mass tended to worsen after transplant with the greatest decline in muscle mass in the first year post-LT. Interestingly, sarcopenia did not influence post-transplant outcomes. Future prospective studies are needed to further understand the natural course of sarcopenia post-LT to guide interventions aiming at reversing post-LT sarcopenia.

Radiological Quantification of Sarcopenic Obesity and its Role in Chronic Liver Disease Severity

RATIONALE AND OBJECTIVES

To define sarcopenic obesity (SaO) among chronic liver disease (CLD) patients via CT and MRI, and assess its impact on liver disease severity.

MATERIALS AND METHODS

CLD patients referred from the Gastroenterology and Hepatology Department diagnosed as chronic hepatitis B (N:101), cirrhosis (N:110), and hepatocellular carcinoma (N:169) with available information on body height, weight, Child-Pugh and MELD scores within 2 weeks of CT or MRI scanning were included in the study. Cross-sectional examinations were retrospectively evaluated for skeletal muscle index (SMI) and visceral adipose tissue area (VATA). The disease severity was assessed by Child-Pugh and MELD scoring.

RESULTS

The rate of sarcopenia and SaO in the cirrhotic patients was higher than that in the chronic hepatitis B patients (p <0.033 and p < 0.004, respectively). The rate of sarcopenia and SaO in HCC patients was higher than that in the chronic hepatitis B patients (p <0.001 and p <0.001, respectively). Sarcopenic patients in Chronic hepatitis B, cirrhotic, and HCC groups had higher MELD scores than nonsarcopenic patients (p <0.035, p <0.023, and p <0.024, respectively). Despite finding a similar increase in Child-Pugh scores in cirrhotic and HCC sarcopenic patients, results were statistically insignificant (p <0.597 and p <0.688). HCC patients with SaO had higher MELD scores than patients with other body composition catagories (p <0.006). Cirrhotic patients with SaO had higher MELD scores than nonsarcopenic obese patients (p <0.049). Chronic hepatitis B patients with obesity had low MELD scores (p <0.035). Cirrhotic and HCC patients with obesity had higher MELD scores (p <0.01 and p <0.024, respectively). Cirrhotic and HCC patients with obesity had higher Child-Pugh scores than nonobese patients but only HCC patients showed statistically significance (p <0.480 and p <0.001).

CONCLUSION

Radiologic evaluation of SaO and harmonizing body composition with MELD scoring is critical in CLD management.

Association between skeletal muscle index prior to liver transplantation and 1-year mortality posttransplant

BACKGROUND

Liver transplantation is the only curative therapy for end-stage liver disease (ESLD). Sarcopenia is often defined as the loss of muscle quantity (skeletal muscle index [SMI]), but muscle attenuation (MA), a surrogate marker of muscle quality, is also decreased in ESLD. We assessed pre-liver transplant SMI and MA and their association with posttransplant mortality, complications, and length of intensive care unit (ICU) and hospital stay.

METHODS

In 169 consecutive patients with ESLD who underwent a liver transplantation between 2007 and 2014, SMI and MA were measured on computed tomography scans at time of placement on the waiting list for liver transplantation. The primary outcome of interest was 1-year posttransplant mortality. Secondary posttransplantation outcomes of interest were complications within 30 days and length of stay in the ICU > 3 days and in the hospital >3 weeks. Logistic and Cox regression analyses were performed.

RESULTS

MA was associated with 1-year posttransplant mortality rate (hazard ratio=0.656, 95% CI=0.464-0.921, P = 0.015). The highest quartile of SMI had a lower odds for the total length of stay in the hospital lasting >3 weeks (odds ratio=0.211, 95% CI=0.061-0.733, P = 0.014). MA was associated with a prolonged ICU stay; this was, however, not statistically significant after adjustment for age, sex, and Model for ESLD score.

CONCLUSION

Lower MA is associated with a longer length of ICU stay and 1-year mortality after liver transplantation, whereas low SMI was associated with a total length of hospital stay.

Newly developed sarcopenia after liver transplantation, determined by a fully automated 3D muscle volume estimation on abdominal CT, can predict post-transplant diabetes mellitus and poor survival outcomes

BACKGROUND

Loss of muscle mass is the most common complication of end-stage liver disease and negatively affects outcomes for liver transplantation (LT) recipients. We aimed to determine the prognostic value of a fully automated three-dimensional (3D) muscle volume estimation using deep learning algorithms on abdominal CT in patients who underwent liver transplantation (LT).

METHODS

This retrospective study included 107 patients who underwent LT from 2014 to 2015. Serial CT scans, including pre-LT and 1- and 2-year follow-ups were performed. From the CT scans, deep learning-based automated body composition segmentation software was used to calculate muscle volumes in 3D. Sarcopenia was calculated by dividing average skeletal muscle area by height squared. Newly developed-(ND) sarcopenia was defined as the onset of sarcopenia 1 or 2 years after LT in patients without a history of sarcopenia before LT. Patients' clinical characteristics, including post-transplant diabetes mellitus (PTDM) and Model for end-stage liver disease score, were compared according to the presence or absence of sarcopenia after LT. A subgroup analysis was performed in the post-LT sarcopenic group. The Kaplan-Meier method was used for overall survival (OS).

RESULTS

Patients with ND-sarcopenia had poorer OS than those who did not (P = 0.04, hazard ratio [HR], 3.34; 95% confidence interval [CI] 1.05 - 10.7). In the subgroup analysis for post-LT sarcopenia (n = 94), 34 patients (36.2%) had ND-sarcopenia. Patients with ND-sarcopenia had significantly worse OS (P = 0.002, HR 7.12; 95% CI 2.00 - 25.32) and higher PTDM occurrence rates (P = 0.02, HR 4.93; 95% CI 1.18 - 20.54) than those with sarcopenia prior to LT.

CONCLUSION

ND-sarcopenia determined by muscle volume on abdominal CT can predict poor survival outcomes and the occurrence of PTDM for LT recipients.

Mechanisms of sarcopenia in liver cirrhosis and the role of myokines

Sarcopenia is a syndrome characterized by a decline in skeletal muscle quantity and/or quality, strength and performance, leading to unfortunate events, such as injurious falls or even death. It is not identical to frailty and malnutrition, even though there is a significant overlap among these syndromes. In patients with liver cirrhosis (LC), sarcopenia is classified as secondary and has been associated with increased morbidity and mortality during the pre- and post-transplantation period. It can be a result of malnutrition, hyperammonemia, low physical activity, endocrine abnormalities, accelerated starvation, metabolic disturbances, altered gut function leading to chronic inflammation, and alcohol abuse. Myokines are peptides mainly synthesized by contracting muscle and adipose tissue cells and may play a key role in the pathophysiology of sarcopenia. More than a hundred myokines have been recognized, but only a few have been investigated. They can be classified as negative regulators, such as myostatin, tumor growth factor-β, activins, growth differentiation factor-11, and positive regulators of muscle growth including follistatin, bone morphogenic proteins, and irisin. So far, only myostatin, follistatin, irisin and decorin have been studied in LC-associated sarcopenia. In this review, we focused on the mechanisms of cirrhosis-related sarcopenia and the role of myokines that have already been studied in the literature, either as markers helping in the diagnostic evaluation of sarcopenia, or as prognostic factors of survival. Standard therapeutic options to prevent or treat sarcopenia in LC are also being reported, as well as the possible therapeutic implication of myokines.

Physical Performance Decline During the Early Posttransplantation Period Affects Survival After Living Donor Liver Transplantation

BACKGROUND

Patient physical performance has been emphasized in liver transplant recipients; however, evidence for living donor liver transplantation (LDLT) patients is lacking. This study investigated the impact of physical performance decline during the early posttransplantation period on survival and risk factors for this decline in LDLT recipients.

METHODS

From national registry data, 2703 LDLT patients were divided into 2 groups based on the change in their Karnofsky performance status (KPS) between 1 and 6 mo posttransplantation: declined KPS (n = 188) and control (n = 2515). Multivariable analyses were conducted to control for confounders, including posttransplantation complications.

RESULTS

Estimated 5-y patient survival rates were 91.6% in the declined KPS group and 96.3% in the control group, favoring the latter ( P = 0.003). The survival hazard of KPS decline was significant in a baseline covariates-adjusted Cox model (hazard ratio [HR], 2.60; 95% confidence interval [CI], 1.37-4.95) and an adjusted model accounting for posttransplantation complications (HR, 3.38; 95% CI, 1.70-6.72). In subgroup analyses, KPS decline independently reduced survival in patients without complications (HR, 3.95; 95% CI, 1.67-9.34), and the trend was similar in patients with complications, although significance was marginal (HR, 3.02; 95% CI, 0.98-9.27). We found that only posttransplantation complications, such as rejection, infection, bile duct complication, and vascular complication, were significant risk factors for KPS decline after LDLT.

CONCLUSIONS

Physical performance decline during the early posttransplantation period independently reduced survival rates, and posttransplantation complications were the only significant risk factors for physical performance decline in LDLT recipients.

From Listing to Recovery: A Review of Nutritional Status Assessment and Management in Liver Transplant Patients

Liver transplantation (LT) is a complex surgical procedure requiring thorough pre- and post-operative planning and care. The nutritional status of the patient before, during, and after LT is crucial to surgical success and long-term prognosis. This review aims to assess nutritional status assessment and management before, during, and after LT, with a focus on patients who have undergone bariatric surgery. We performed a comprehensive topic search on MEDLINE, Ovid, In-Process, Cochrane Library, EMBASE, and PubMed up to March 2023. It identifies key factors influencing the nutritional status of liver transplant patients, such as pre-existing malnutrition, the type and severity of liver disease, comorbidities, and immunosuppressive medications. The review highlights the importance of pre-operative nutritional assessment and intervention, close nutritional status monitoring, individualised nutrition care plans, and ongoing nutritional support and monitoring after LT. The review concludes by examining the effect of bariatric surgery on the nutritional status of liver transplant recipients. The review offers valuable insights into the challenges and opportunities for optimising nutritional status before, during, and after LT.

Liver transplantation in the patient with physical frailty

Frailty is a decline in functional reserve across multiple physiological systems. A key component of frailty is sarcopenia, which denotes a loss of skeletal muscle mass and impaired contractile function that ultimately result in physical frailty. Physical frailty/sarcopenia are frequent and contribute to adverse clinical outcomes before and after liver transplantation. Frailty indices, including the liver frailty index, focus on contractile dysfunction (physical frailty), while cross-sectional image analysis of muscle area is the most accepted and reproducible measure to define sarcopenia. Thus, physical frailty and sarcopenia are interrelated. The prevalence of physical frailty/sarcopenia is high in liver transplant candidates and these conditions have been shown to adversely impact clinical outcomes including mortality, hospitalisations, infections, and cost of care both before and after transplantation. Data on the prevalence of frailty/sarcopenia and their sex- and age-dependent impact on outcomes are not consistent in patients on the liver transplant waitlist. Physical frailty and sarcopenic obesity are frequent in the obese patient with cirrhosis, and adversely affect outcomes after liver transplantation. Nutritional interventions and physical activity remain the mainstay of management before and after transplantation, despite limited data from large scale trials. In addition to physical frailty, there is recognition that a global evaluation including a multidisciplinary approach to other components of frailty (e.g., cognition, emotional, psychosocial) also need to be addressed in patients on the transplant waitlist. Recent advances in our understanding of the underlying mechanisms of sarcopenia and contractile dysfunction have helped identify novel therapeutic targets.

Muscle quality determined by computed tomography predicts short-term and long-term survival after liver transplantation

Sarcopenia, the loss of muscle mass and quality, contributes to worse clinical outcome in patients with end-stage liver disease, but its impact on short- and long-term survival remains insufficiently understood. The aim of this study was to evaluate the development of computed tomography (CT) muscle parameters and their impact on short-term and long-term survival after liver transplantation. This retrospective study included patients with liver transplantation between 2011 and 2015 and a pre-transplant CT scan. Clinical characteristics, CT muscle mass and density were assessed pre-transplant, and in available CT scans at short-term (11 months) and long-term follow-up (56 months). Overall, 93/152 (61%) patients (109 male, 55 ± 10 years) suffered from sarcopenia pre-transplant. In short- (n = 50) and long-term follow-up (n = 52) the muscle mass (- 2.65 cm²/m² 95% CI [- 4.52, - 0.77], p = 0.007; - 2.96 cm²/m² [- 4.7, - 1.23], p = 0.001, respectively), and muscle density (- 3 HU [- 6, - 1], p = 0.007; - 2 HU [- 4, 0], p = 0.069) decreased. Myosteatosis was associated with a higher post-transplant mortality (survival probability: 3 months 72% vs. 95%, 1 year 63% vs. 90%, 5 years 54% vs. 84%, p = 0.001), while muscle mass was not. In conclusion, muscle mass and quality did not improve after transplant. Muscle quality predicts short- and long-term survival and could help to identify a patient's risk profile.

[Comparison of different tools for the evaluation of malnutrition and sarcopenia in patients with liver cirrhosis]

INTRODUCTION

malnutrition and sarcopenia are frequent in the population with liver cirrhosis and have a negative impact on the performance status and life expectancy of these patients. There are multiple assessment tools for malnutrition and sarcopenia in cirrhosis.

OBJECTIVE

to assess malnutrition and sarcopenia in liver cirrhosis and to compare the accuracy of diagnostic tools in this population.

METHOD

a cross-sectional analytical study was conducted with convenience sampling by using continuous inclusion of patients with liver cirrhosis in a tertiary care center during December 2018 to May 2019. The nutritional assessment was carried out with arm anthropometry, body mass index (BMI), and the algorithm of the Royal Free Hospital Subjective Global Assessment (RFH-SGA). For the evaluation of sarcopenia, the hand grip strength test with a hand dynamometer was applied. The results were reported in measures of central tendency expressed in frequency and percentage.

RESULTS

a total of 103 patients were included with a predominance of the male gender (79.6 %) and a mean age of 51 years (± 10). The etiology of liver cirrhosis corresponded more frequently to alcohol consumption (68 %) and most of the patients were Child-Pugh C (57.3 %) with a mean MELD of 21.9 (± 8.9). A mean BMI with dry weight of 25.2 kg/m2 was reported, and with respect to the WHO classification by BMI, 7.8 % were underweight and 59.2 % were malnourished by RFH-SGA. Sarcopenia was present in 88.3 % using the hand grip strength test, for which a mean of 18.99 kg was found. A Kendall's Tau-b rank correlation coefficient was performed between BMI and RFH-SGA, which showed no statistically significant association, as well as between mean arm muscle circumference percentiles and hand grip strength.

CONCLUSIONS

global assessment in liver cirrhosis should include screening for malnutrition and sarcopenia, for which validated, accessible and safe application tools should be used, such as anthropometric assessment, RFH-SGA, and hand grip strength.

Nutritional Strategies to Manage Malnutrition and Sarcopenia following Liver Transplantation: A Narrative Review

Persisting or newly developed malnutrition and sarcopenia after liver transplant (LT) are correlated with adverse health outcomes. This narrative review aims to examine the literature regarding nutrition strategies to manage malnutrition and sarcopenia after LT. The secondary aims are to provide an overview of the effect of nutrition strategies on the incidence of infections, hospital length of stay (LOS), acute cellular rejection (ACR), and mortality after LT. Four databases were searched. A total of 25 studies, mostly of mid-high quality, were included. Six studies found a beneficial effect on nutritional parameters using branched-chain amino acids (BCAA), immunomodulating diet (IMD), or enteral nutrition (EN) whereas two studies using beta-hydroxy-beta-methylbutyrate (HMB) found a beneficial effect on muscle mass and function. Fourteen studies using pre- or pro-biotics, IMD, and EN were effective in lowering infection and six studies using IMD, BCAA or HMB reported reduced hospital LOS. Finally, four studies using HMB and vitamin D were effective in reducing ACR and one study reported reduced mortality using vitamin D after LT. In conclusion, nutritional intervention after LT has different beneficial effects on malnutrition, sarcopenia, and other advert outcomes. Additional large and well-constructed RCTs using validated tools to assess nutritional status and sarcopenia are warranted to ensure more robust conclusions.

Sarcopenia and Frailty in Cirrhosis

Sarcopenia and frailty are frequent in cirrhosis, and both contribute to increased morbidity and mortality. The complex pathogenesis of sarcopenia in cirrhosis is mainly determined by hyperammonemia and malnutrition. Sarcopenia/frailty screening and reevaluation should be undertaken in all cirrhotic patients. Frailty tests are useful in the ambulatory setting, whereas the computed tomography scan is the diagnostic gold standard for sarcopenia. To manage sarcopenia/frailty, a multidisciplinary team should develop a personalized comprehensive care plan that includes patient education, protein/calorie intake goals, late evening meals, exercise programs, and micronutrient replenishment. In selected patients, branched-chain amino acid and testosterone supplements may also be beneficial.

Liver transplantation for non-alcoholic fatty liver disease: indications and post-transplant management

Non-alcoholic fatty liver disease (NAFLD) is currently the fastest growing indication to liver transplantation (LT) in Western Countries, both for end stage liver disease and hepatocellular carcinoma. NAFLD/non-alcoholic steatohepatitis (NASH) is often expression of a systemic metabolic syndrome; therefore, NAFLD/NASH patients require a multidisciplinary approach for a proper pre-surgical evaluation, which is important to achieve a post-transplant outcome comparable to that of other indications to LT. NAFLD/NASH patients are also at higher risk of post-transplant cardiovascular events, diabetes, dyslipidemia, obesity, renal impairment and recurrent NASH. Lifestyle modifications, included diet and physical activity, are key to improve survival and quality of life after transplantation. A tailored immunosuppressive regimen may be proposed in selected patients. Development of new drugs for the treatment of recurrent NASH is awaited.

Does Exercise Training Improve Physical Fitness and Health in Adult Liver Transplant Recipients? A Systematic Review and Meta-analysis

BACKGROUND

The impaired physical fitness of end-stage liver disease patients often persists after liver transplantation (LT) and compromises posttransplant recovery. This systematic review and meta-analysis evaluated evidence supporting the potential of exercise training to improve physical fitness and health-related quality of life (HRQOL) after LT.

METHODS

Bibliographic searches identified all randomized controlled trials (RCTs) comparing aerobic and strength training versus usual care after LT. Risk of bias was assessed, and study outcomes measuring physical fitness and HRQOL were extracted. Meta-analysis was performed if at least 3 studies reported on an outcome.

RESULTS

Eight RCTs (n = 334) were identified. Methodological study quality varied and was poorly reported. Meta-analyses showed a trend for favorable effects of exercise on cardiorespiratory fitness (peak oxygen uptake or 6-min walking distance; 6 studies, n = 275; standardized mean difference: 0.23, 95% confidence interval [CI], -0.01 to 0.48) and of strength training either or not combined with aerobic training on muscular fitness (dynamometry-assessed muscle strength or 30-s sit-to-stand test; 3 studies, n = 114; standardized mean difference: 0.34, 95% CI, -0.03 to 0.72). A favorable effect was found for exercise on the Short-Form Health Survey-36 HRQOL physical function subcomponent (3 studies, n = 194; mean difference: 9.1, 95% CI, 0.3-17.8). No exercise-related adverse events were observed.

CONCLUSIONS

RCTs indicate that exercise training in LT recipients is safe, improves physical function aspects of HRQOL, and may benefit cardiorespiratory and muscular fitness. The strength of evidence is, however, limited by the low number of patients and study quality. More adequately powered, high-quality RCTs are warranted.

Skeletal muscle mass index as a predictor of long-term cirrhosis onset in young non-cirrhotic males with acute-on-chronic liver failure

Background

The relationship between skeletal muscle mass index (SMI) and cirrhosis incidence in patients with non-cirrhotic acute-on-chronic (ACLF) has not been clarified. This study aimed to assess the predictive value of SMI on the incidence of long-term cirrhosis in male non-cirrhotic ACLF patients.

Materials and methods

Male ACLF patients who were free of liver cirrhosis were retrospectively included in this study. Univariate and multivariate logistic analyses were conducted to determine the risk factors for the long-term (1-year) development of cirrhosis. The receiver operating characteristic curves (ROC) were used to assess the ability of SMI levels to predict the incidence of cirrhosis. Restricted triple spline (RCS) described the dose-response relationship between SMI and the risk of cirrhosis. Subgroup analysis was stratified by age (≤ 40 years and > 40 years).

Results

A total of 230 subjects were included in this study, of whom 45.2% (104/230) were diagnosed with cirrhosis within 360 days. Patients who progressed to cirrhosis had a lower SMI [46.1 ± 6.9 versus 49.2 ± 6.5 cm²/m², P = 0.001] and a higher proportion of sarcopenia (19.2% versus 6.3%, P = 0.003). In multivariate logistic regression, SMI remained a protective agent against 360-days progression to cirrhosis in males with ACLF after adjustment (OR 0.950, 95% CI: 0.908-0.994, P < 0.05). SMI exerted a non-linear dose-dependent effect on the risk of cirrhosis. The area under the ROC curve (AUC) for the L3-SMI to predict the incidence of cirrhosis in male non-cirrhotic ACLF patients was 0.636 (P < 0.001). We observed significant differences in SMI among male ACLF patients in different age groups. Further subgroup analysis by age revealed that lower SMI was associated with the 1-year incidence of cirrhosis in male ACLF patients aged less than 40 years (OR 0.908, 95% CI: 0.842-0.979, P < 0.05), whereas SMI did not affect the 1-year risk of cirrhosis in older subjects (age > 40 years).

Conclusion

A higher SMI represents an independent protective factor for developing long-term cirrhosis in male ACLF patients who do not experience cirrhosis, especially in those under 40 years of age.

The effect of sarcopenia and serum myokines on prognosis and survival in cirrhotic patients: a multicenter cross-sectional study

OBJECTIVE

Sarcopenia is one of the most significant contributors to morbidity in patients with chronic liver disease. Serum myokines are potential biomarkers for detecting early sarcopenia. We aimed to investigate the relationship between serum myokines and cirrhosis-related mortality in the early stages of the disease.

METHODS

In total, 262 patients and 50 healthy controls were enrolled in this study, which was designed as a multicenter cross-sectional study. At the beginning of the study, sarcopenia was defined by computed tomography scans using the third lumbar vertebra skeletal muscle index. Serum myostatin, irisin, and follistatin levels, nutritional status of the patients, and muscle strength as measured by the handgrip test were recorded. Cirrhosis-related mortality and overall survival were evaluated in the fourth year of the study as the second checkpoint of cross-sectional analysis.

RESULTS

A total of 145 (55.3%) patients were diagnosed with sarcopenia. Multivariate analysis revealed that low BMI, high levels of myostatin, and decreased irisin levels were independent predictors of sarcopenia. While serum irisin level was the most predictive parameter in terms of 4th-year cirrhosis-related mortality in the CHILD A group, serum myostatin levels were found more indicative in the CHILD BC group regardless of sarcopenia status ( P < 0.001).

CONCLUSION

Serum myostatin levels predict sarcopenia in all stages of cirrhosis. Serum irisin levels can also be used as a potential biomarker to predict both treatable sarcopenia and cirrhosis-related mortality in CHILD A patients.

The role of acute in-patient rehabilitation on short-term outcomes after liver transplantation: A systematic review of the literature and expert panel recommendations

BACKGROUND

The indication and surgical complexity of orthotopic liver transplantation underscore the need for strategies to optimize the recovery for transplant recipients. We conducted a systematic review aimed at identifying, evaluating, and synthesizing the evidence examining the effect of in-patient rehabilitation for liver transplant recipients and provide related practice recommendations.

METHODS

Health research databases were systematically reviewed for studies that included adults who received liver transplantation and participated in acute, post-transplant rehabilitation. Postoperative morbidity, mortality, length of hospital stay, length of intensive care unit stay, and other markers of surgical recovery were extracted. Practice recommendations are provided by an international panel using GRADE.

RESULTS

Twelve studies were included in the review (including 3901 participants). Rehabilitation interventions varied widely in design and composition; however, details regarding intervention delivery were poorly described in general. The quality of evidence was rated as very low largely owing to "very serious" imprecision, poor reporting, and limited data from comparative studies. Overall, the studies suggest that in-patient rehabilitation for recipients of liver transplantation is safe, tolerable, and feasible, and may benefit functional outcomes.

CONCLUSION

Two practice recommendations related to in-patient rehabilitation following LT were yielded from this review: (1) it is safe, tolerable, and feasible; and (2) it improves postoperative functional outcomes. Each of the recommendations are weak and supported by low quality of evidence. No recommendation could be made related to benefits or harms for clinical, physiological, and other outcomes. Adequately powered and high quality randomized controlled trials are urgently needed in this area.

Sarcopenic visceral obesity is associated with increased post-liver transplant mortality in acutely ill patients with cirrhosis

"Sarcopenic obesity" refers to a condition of low muscle mass in the context of obesity, though may be difficult to assess in patients with cirrhosis who are acutely ill. We aimed to define sarcopenic visceral obesity (SVO) using CT-based skeletal muscle index (SMI) and visceral-to-subcutaneous adipose tissue ratio (VSR) to examine its association with post-transplant mortality. We analyzed 116 adult inpatients with cirrhosis who were urgently listed and transplanted between 1/2005 and 12/2017 at 4 North American transplant centers. SVO was defined as patients with sarcopenia (SMI <50 cm2 /m2 in men and <39 cm2 /m2 in women) and visceral obesity (VSR ≥ 1.54 in men and ≥1.37 in women). The percentage who met criteria for sarcopenia, visceral obesity, and SVO were 45%, 42%, and 20%, respectively. Cumulative rates of post-transplant mortality were higher in patients with SVO compared to patients with sarcopenia or visceral obesity alone at 36 months (39% vs. 14% vs. 8%) [logrank p = .01]. In univariable regression, SVO was associated with post-transplant mortality (HR 2.92, 95%CI 1.04-8.23) and remained significant after adjusting for age, sex, diabetes, encephalopathy, hepatocellular carcinoma, and MELD-Na (HR 3.50, 95%CI 1.10-11.15). In conclusion, SVO is associated with increased post-transplant mortality in acutely ill patients with cirrhosis.

Sarcopenia in chronic advanced liver diseases: A sex-oriented analysis of the literature

Sarcopenia, defined as progressive and generalized loss of muscle mass and strength, is common in chronic liver disease. It significantly impacts the quality of life and increases the risk of liver-related complications and mortality in cirrhotic patients. Moreover, recent studies showed a negative impact of sarcopenia on patients awaiting liver transplantation (LT), on post-LT outcomes, and on response to hepatocellular carcinoma therapies. Data about the influence of sex on the incidence, prevalence, diagnosis and treatment of sarcopenia in chronic liver diseases are poor and conflicting. The aims of this review of the literature are to define sex differences in sarcopenic cirrhotic patients and to highlight the necessity of a sex stratified analysis in future studies. This analysis of the literature showed that most of the studies are retrospective, with a higher prevalence of sarcopenia in males, probably due to anatomical differences between the sexes. Moreover, diagnostic criteria for sarcopenia are different between studies, as there is not a defined cut-off and, as a consequence, no comparable results. In conclusion, sex seems to have an impact on sarcopenia, and future studies must accurately investigate its role in identifying and treating high-risk patients, reducing the negative impact of sarcopenia on the survival and quality of life of cirrhotic patients.

Extrahepatic organs in the development of non-alcoholic fatty liver disease in liver transplant patients

BACKGROUND AND OBJECTIVE

Non-alcoholic fatty liver disease (NAFLD) is highly prevalent in patients who undergo liver transplantation (LT). Whereas there is huge data on NAFLD, little is known about NAFLD in LT. In this review, we aim to explore extrahepatic organs and their potential mechanisms in the development of NAFLD in LT patients and discuss current limitations in preclinical and clinical scenarios with suggestions for future study.

METHODS

The following keywords, such as NAFLD, NASH, liver transplant, therapy, pathogenesis and biomarkers, were set for literature retrieval. The articles which were published articles in English till 25th June 2020 in PubMed database were included, and there is no limit for the study design type.

KEY CONTENT AND FINDINGS

Following LT, there are significant shifts in the microbiota and farnesoid X receptor may be a potential therapeutic target for NAFLD in LT settings. The roles of probiotics and diet on NALFD remain inconclusive in LT background. Nevertheless, the adipokines and cytokines disorder and local insulin resistance of adipose tissue may contribute to NAFLD process. Bariatric surgeries are promising in controlling de novo and recurrent NAFLD with significant reduction in abdominal adipose tissue, despite the optimal timing is inconclusive in LT cases. Furthermore, circumstantial evidence indicates that miRNA-33a may function as a mediator bridging sarcopenia and NAFLD of post-LT. β-Hydroxy-β-Methyl-Butyrate treatment could improve muscle status in graft recipients and shows protective potential for NAFLD in LT settings.

CONCLUSIONS

Gut, adipose tissue and muscle are intricately intertwined in promoting NAFLD in LT cases. Further animal studies are needed to deepen our understanding of mechanisms in multi-organ crosstalk. High quality clinical trials are warrant for making guidelines and developing management strategies on NAFLD after LT.

Renal dysfunction independently predicts muscle mass loss in patients following liver transplantation

BACKGROUND: Liver transplantation (LT) is the only curative treatment for cirrhosis. However, the presence of complications can impact outcomes following LT. Sarcopenia, or muscle mass loss, is highly prevalent in patients with cirrhosis and is associated with longer hospitalization stays and a higher infection rate post-surgery. We aimed to identify patients at higher risk of early sarcopenia post-LT. METHODS: This retrospective study included 79 cirrhotic patients who underwent LT. Muscle mass was evaluated using the third lumbar spine vertebra skeletal muscle mass index (SMI) and sarcopenia was defined using established cut-off values. Computerized tomography (CT) scans performed within six-month peri-operative period (three months pre- and post-LT) were included in the study. Complications and comorbidities were collected and correlated to SMI post-LT and predictive models for SMI post-LT were constructed. RESULTS: The overall prevalence of sarcopenia was 46% and 62% before and after LT, respectively. Newly developed sarcopenia was found in 42% of patients. Post-LT sarcopenia was associated with longer hospital stays (54±37 vs 29±10 days, p = 0.002), higher number of infection (3±1 vs 1±2, p = 0.027), and greater number of complications (5±2 vs 3±2, p <0.001) compared to absence of sarcopenia. Multivariate analyses showed that the SMI post-LT was independently associated with pre-LT renal function markers, the glomerular filtration rate (GFR) and creatinine (Model 1, GFR: β = 0.33; 95% CI = 0.04–0.17; p = 0.003; Model 2, Creatinine: β = –0.29; 95% CI = –0.10 to –0.02; p = 0.009). CONCLUSIONS: The present study highlights the potential role of renal dysfunction in the development and persistence of sarcopenia after LT.

European Working Group on Sarcopenia in Older People (EWGSOP2) Criteria With Population-Based Skeletal Muscle Index Best Predicts Mortality in Asians With Cirrhosis

BACKGROUND/AIMS

Multiple definitions of sarcopenia exist and the acceptable criterion that best predicts outcome is lacking. We estimated the prevalence of sarcopenia based on four criteria and assessed their utility in predicting mortality in cirrhotics.

METHODS

In a prospective observational study, consecutive Asian patients with cirrhosis underwent testing for handgrip strength (HGS) and estimation of skeletal muscle index (SMI) using computed tomography at the third lumbar vertebra. Sarcopenia was defined based on the Western cut-off (WC; SMI < 50 cm²/m² for men and <39 cm²/m² for women), Asian cut-off (AC; SMI < 36.5 cm²/m² for men and 30.2 cm²/m² for women), European Working Group on Sarcopenia in Older People-2nd meeting (EWGSOP2) definition incorporating low HGS (<27 kg for men and <16 kg for women) with low SMI (defined by the WC), and EWGSOP2 definition with low HGS and low SMI (defined by AC). Risk factors for mortality were assessed using multivariate Cox-proportional hazards.

RESULTS

We included 219 patients with cirrhosis (168 men; mean age 42.6 years) with 50.2% patients having decompensation. Alcohol was the commonest aetiology (33.3%). The prevalence of sarcopenia was highest with the WC (men: 82.1%; women: 62.7%). There was a weak concordance among all criteria (Fleiss' kappa 0.23, 95% confidence interval [CI] 0.10-0.37). Overall, 12-month survival was 86.1% (81.1-91.3%) over a median (interquartile range) follow-up of 12 (6-15) months. Ascites (hazards ratio [HR] 6.27 [95% CI 1.6-24.1]; P < 0.007) and SMI (HR 0.92 [0.85-0.98]; P = 0.021) were independent predictors of mortality. The 12-month mortality rate was higher in patients with sarcopenia, irrespective of criteria (log rank P < 0.05). Low HGS and low SMI (defined by AC) was the best for predicting mortality (HR 3.04 [1.43-6.43]; P = 0.004).

CONCLUSION

A weak concordance exists amongst various diagnostic definitions of sarcopenia. Sarcopenia diagnosed by a combination of low HGS and population-specific SMI cut-off (AC) best predicts mortality.

Alterations in Autophagy and Mammalian Target of Rapamycin (mTOR) Pathways Mediate Sarcopenia in Patients with Cirrhosis

Background and aims

The pathophysiology of sarcopenia in cirrhosis is poorly understood. We aimed to evaluate the histological alterations in the muscle tissue of patients with cirrhosis and sarcopenia, and identify the regulators of muscle homeostasis.

Methods

Computed tomography images at third lumbar vertebral level were used to assess skeletal muscle index (SMI) in 180 patients. Sarcopenia was diagnosed based on the SMI cut-offs from a population of similar ethnicity. Muscle biopsy was obtained from the vastus lateralis in 10 sarcopenic patients with cirrhosis, and the external oblique in five controls (voluntary kidney donors during nephrectomy). Histological changes were assessed by hematoxylin and eosin staining and immunohistochemistry for phospho-FOXO3, phospho-AKT, phospho-mTOR, and apoptosis markers (annexin V and caspase 3). The messenger ribonucleic acid (mRNA) expressions for MSTN, FoxO3, markers of ubiquitin-proteasome pathway (FBXO32, TRIM63), and markers of autophagy (Beclin-1 and LC3) were also quantified.

Results

The prevalence of sarcopenia was 14.4%. Muscle histology in sarcopenics showed atrophic angulated fibers (P = 0.002) compared to controls. Immunohistochemistry showed a significant loss of expression of phospho-mTOR (P = 0.026) and an unaltered phospho-AKT (P = 0.089) in sarcopenic patients. There were no differences in the immunostaining for annexin-V, caspase-3, and phospho-FoxO3 between the two groups. The mRNA expressions of MSTN and Beclin-1 were higher in sarcopenics (P = 0.04 and P = 0.04, respectively). The two groups did not differ in the mRNA levels for TRIM63, FBXO32, and LC3.

Conclusions

Significant muscle atrophy, increase in autophagy, MSTN gene expression, and an impaired mTOR signaling were seen in patients with sarcopenia and cirrhosis.

Impact of pretransplant frailty and sarcopenia on the post-transplant prognosis of patients with liver cirrhosis: a systematic review

INTRODUCTION

Frailty and sarcopenia associate with increased mortality in patients with liver cirrhosis on the transplant waitlist. We conducted a systematic review on the impact of pretransplant frailty and sarcopenia on post-transplant outcomes in adult patients with liver cirrhosis.

METHODS

We performed a search in Medline, Embase and Cochrane Central. Of the 12276 references initially recovered, 34 were included.

RESULTS

Frailty and sarcopenia presented a negative impact on post-transplant outcomes and seemed to associate with an overall two-fold reduction in early and 50% reduction in late survival, for severe conditions, according to the largest cohorts. These patients required longer ICU and hospitalization time, had higher rates of sepsis and respiratory complications and lower graft-survival. The reversibility of frailty depended on the severity of functional impairment and on the co-morbidities contributing to frailty. Reversibility of sarcopenia occurred in only a minority of patients, in unbiased studies.

CONCLUSION

Frailty and sarcopenia are double-edged swords: patients with frailty/sarcopenia should be prioritized for liver transplantation due to increased mortality on the waitlist; however, severe frailty/sarcopenia may justify delisting because it associates with dismal prognosis post-liver transplantation. Patients presenting mild to moderate frailty/sarcopenia, should be submitted to liver transplantation before those conditions worsen to a level that significantly impacts post-liver transplantation outcomes.

Myostatin in combination with creatine phosphokinase or albumin may differentiate patients with cirrhosis and sarcopenia

In patients with liver cirrhosis (LC), sarcopenia is correlated with frequent complications and increased mortality. Myostatin, a myokine, is a potential biomarker of skeletal mass and/or sarcopenia. The aim of this study was to examine the association between myostatin and muscle mass and evaluate myostatin as a biomarker of sarcopenia in LC. Skeletal muscle index (SMI) and myosteatosis were evaluated by computed tomography scan. Muscle quantity and quality along with muscle strength and function were used to diagnose sarcopenia. Serum myostatin was measured by ELISA. One hundred and fifteen consecutive patients with LC [72.2% male, median age 59 yr (IQR 52-67), MELD 12 (8-16), 28.7% with compensated LC] were included. Low SMI was diagnosed in 49.6% and sarcopenia in 34.8% (21.7% severe). Myostatin levels were lower in low (P < 0.001) compared with patients with normal SMI and were strongly correlated with SMI in MELD score ≥ 15 (r = 0.571, P < 0.001). Myostatin was also lower in patients with sarcopenia compared with those without (P < 0.001) and even lower in severe sarcopenia (P < 0.001). In multivariate analysis, myostatin, age, and albumin remained significant predictors of low SMI after adjustment for sex, MELD, and creatine phosphokinase (CPK). Similarly, myostatin and age predicted sarcopenia after adjustment for sex, MELD, CPK, and albumin. The ratios log₁₀myostatin-to-CPK or albumin-to-myostatin were found to have acceptable diagnostic accuracy in ruling out sarcopenia in total patients. However, the best diagnostic performance was shown in MELD ≥ 15 (AUROC 0.829 or 0.801, respectively). Myostatin is independently associated with both skeletal muscle mass and sarcopenia. Myostatin in combination with CPK or albumin are good surrogate markers in excluding sarcopenia.NEW & NOTEWORTHY Serum levels of myostatin were significantly lower in cirrhotic patients with impaired skeletal mass index (SMI) and sarcopenia than those without. Serum levels of myostatin have a positive correlation with SMI. Myostatin levels are independently associated with sarcopenia, diagnosed according to the latest criteria, in patients with cirrhosis. Myostatin in combination with creatine phosphokinase or albumin have good accuracy excluding sarcopenia in patients with cirrhosis.

Sarcopenia adversely impacts postoperative complications in living-donor liver transplantation recipients

Despite technological and immunological innovations, living-donor liver transplant (LDLT) recipients still face substantial risk of postoperative complications. Sarcopenia is being recognized more and more as a biomarker that correlates with poor outcomes in surgical patients. The purpose of this study was to evaluate the relationship between sarcopenia and significant surgical complications in LDLT recipients. This retrospective review included patients who had received LDLT at our institute from 2005 to 2017. Sarcopenia was assessed using the psoas muscle index (PMI) in cross-sectional images. ROC curve analysis was used to determine the ability of PMI to predict postoperative complications. Correlations between major postoperative complications and sarcopenia were evaluated using regression analysis. A total of 271 LDLT recipients were included. No significant differences were found between PMI and major postoperative complications in male patients. Female recipients with major postoperative complications had significantly lower mean PMI values (P = 0.028), and the PMI cut-off value was 2.63 cm²/m². Postoperative massive pleural effusion requiring pigtail drainage occurred more frequently in the sarcopenia group than in the non-sarcopenia group (P = 0.003). 1-, 3-, 5- and 10-year overall survival rates in female were significantly poorer in the sarcopenia group (n = 14) compared with the non-sarcopenia group (n = 108), at 92.9% versus 97.2%, 85.7% versus 95.4%, 85.7% versus 92.5% and 70.1 versus 82.0%, respectively (P = 0.041) and 94.6%, 89.9%, 85.9% and 78.5% in male patients. Sarcopenia is associated with a significantly higher risk of major postoperative complications in females. PMI and sarcopenia together are predictive of major postoperative complications and survival rates in female LDLT recipients.

Nonalcoholic Fatty Liver Disease after Liver Transplant

Nonalcoholic fatty liver disease (NAFLD) is one of the most common causes of chronic liver disease in the world. The rising prevalence of nonalcoholic steatohepatitis (NASH) has led to a 170% increase in NASH cirrhosis as the listing indication for liver transplantation from 2004 to 2013. As of 2018, NASH has overtaken hepatitis C as an indication for liver transplantation in the USA. After liver transplantation, the allograft often develops recurrent NAFLD among patients with known NASH cirrhosis. In addition to recurrent disease, de novo NAFLD has been reported in patients with other indications for liver transplantation. In this review, we will discuss the risk factors associated with recurrent and de novo NAFLD, natural course of the disease, and management strategies after liver transplantation.

Nutritional Evaluation and Treatment of the Cirrhotic Patient

Malnutrition and sarcopenia that lead to functional deterioration, frailty, and increased risk for complications and mortality are common in cirrhosis. Sarcopenic obesity, which is associated with worse outcomes than either condition alone, may be overlooked. Lifestyle intervention aiming for moderate weight reduction can be offered to obese compensated cirrhotic patients, with diet consisting of reduced caloric intake, achieved by reduction of carbohydrate and fat intake, while maintaining high protein intake. Dietary and moderate exercise interventions in patients with cirrhosis are beneficial. Cirrhotic patients with malnutrition should have nutritional counseling, and all patients should be encouraged to avoid a sedentary lifestyle.

Sarcopenia in Children With End-Stage Liver Disease on the Transplant Waiting List

Sarcopenia predicts morbidity and mortality in adults with end-stage liver disease (ESLD) and is determined by total psoas muscle area (tPMA) measurement from computed tomography (CT) imaging. Recently developed pediatric age- and sex-specific tPMA growth curves provide the opportunity to ascertain prevalence and impact of sarcopenia in children awaiting liver transplantation (LT). This retrospective single-center study evaluated sarcopenia in children between 1 and 16 years with ESLD and a clinically indicated abdominal CT less than 3 months before first isolated LT. Sarcopenia was defined as tPMA z score less than -2 measured at the intervertebral L4-5 level. Patient demographic, biochemical, and outcome data were recorded. tPMA was compared with other measures of nutritional status using univariate and multivariate logistic analyses. Outcome measures included 1-year morbidity events and mortality after LT. CT images from 25 (64% female) children with median age of 5.50 (interquartile range [IQR], 3.75-11.33) years were reviewed. Ten children (40%) had a tPMA z score less than -2. Sarcopenia was associated with lower z scores for weight (odds ratio [OR], 0.38; P = 0.02), height (OR, 0.32; P = 0.03), and nutritional support before LT (OR, 12.93; P = 0.01). Sarcopenic children had a longer duration of pediatric intensive care unit (PICU) stay (3.50 [IQR, 3.00-6.00] versus 2.00 [IQR, 2.00-3.50] days; P = 0.03). Sarcopenia was prevalent in 40% of children with ESLD awaiting LT, and lower tPMA z score was associated with deficient anthropometrics and need for nutritional support before LT. Post-LT PICU duration was increased in children with sarcopenia, reflecting adverse outcomes associated with muscle loss. Further studies are needed to elucidate the underlying mechanisms of sarcopenia in children with ESLD.

Definition of Sarcopenia in Chronic Liver Disease

Sarcopenia, which is characterized by decline in muscle mass, muscle strength, and physical performance, is common in patients with chronic liver disease (CLD) and is associated with poor clinical outcomes. Several consensus definitions for community-dwelling elderly people have been proposed, and these recommend the use of various tools and tests to assess muscle properties and performance. These measurement tools have also been applied in patients with CLD and have been useful for predicting prognosis. However, sarcopenia and its diagnostic criteria specific to patients with CLD have not yet been clearly defined. In addition, fluid retention and body composition should be considered when sarcopenia is assessed in patients with CLD. This review aims to introduce definitions of sarcopenia and diagnostic tools used in patients with CLD.

An Overview of the Molecular Mechanisms Contributing to Musculoskeletal Disorders in Chronic Liver Disease: Osteoporosis, Sarcopenia, and Osteoporotic Sarcopenia

The prevalence of osteoporosis and sarcopenia is significantly higher in patients with liver disease than in those without liver disease and osteoporosis and sarcopenia negatively influence morbidity and mortality in liver disease, yet these musculoskeletal disorders are frequently overlooked in clinical practice for patients with chronic liver disease. The objective of this review is to provide a comprehensive understanding of the molecular mechanisms of musculoskeletal disorders accompanying the pathogenesis of liver disease. The increased bone resorption through the receptor activator of nuclear factor kappa (RANK)-RANK ligand (RANKL)-osteoprotegerin (OPG) system and upregulation of inflammatory cytokines and decreased bone formation through increased bilirubin and sclerostin and lower insulin-like growth factor-1 are important mechanisms for osteoporosis in patients with liver disease. Sarcopenia is associated with insulin resistance and obesity in non-alcoholic fatty liver disease, whereas hyperammonemia, low amount of branched chain amino acids, and hypogonadism contributes to sarcopenia in liver cirrhosis. The bidirectional crosstalk between muscle and bone through myostatin, irisin, β-aminoisobutyric acid (BAIBA), osteocalcin, as well as the activation of the RANK and the Wnt/β-catenin pathways are associated with osteosarcopenia. The increased understandings for these musculoskeletal disorders would be contributes to the development of effective therapies targeting the pathophysiological mechanism involved.

The Synergy between Organ-on-a-Chip and Artificial Intelligence for the Study of NAFLD: From Basic Science to Clinical Research

Non-alcoholic fatty liver affects about 25% of global adult population. On the long-term, it is associated with extra-hepatic compliances, multiorgan failure, and death. Various invasive and non-invasive methods are employed for its diagnosis such as liver biopsies, CT scan, MRI, and numerous scoring systems. However, the lack of accuracy and reproducibility represents one of the biggest limitations of evaluating the effectiveness of drug candidates in clinical trials. Organ-on-chips (OOC) are emerging as a cost-effective tool to reproduce in vitro the main NAFLD's pathogenic features for drug screening purposes. Those platforms have reached a high degree of complexity that generate an unprecedented amount of both structured and unstructured data that outpaced our capacity to analyze the results. The addition of artificial intelligence (AI) layer for data analysis and interpretation enables those platforms to reach their full potential. Furthermore, the use of them do not require any ethic and legal regulation. In this review, we discuss the synergy between OOC and AI as one of the most promising ways to unveil potential therapeutic targets as well as the complex mechanism(s) underlying NAFLD.

Sarcopenia in chronic liver disease: mechanisms and countermeasures

Sarcopenia, a condition of low muscle mass, quality, and strength, is commonly found in patients with cirrhosis and is associated with adverse clinical outcomes including reduction in quality of life, increased mortality, and posttransplant complications. In chronic liver disease (CLD), sarcopenia is most commonly defined through the measurement of the skeletal muscle index of the third lumbar spine. A major contributor to sarcopenia in CLD is the imbalance in muscle protein turnover, which likely occurs due to a decrease in muscle protein synthesis and an elevation in muscle protein breakdown. This imbalance is assumed to arise due to several factors including accelerated starvation, hyperammonemia, amino acid deprivation, chronic inflammation, excessive alcohol intake, and physical inactivity. In particular, hyperammonemia is a key mediator of the liver-gut axis and is known to contribute to mitochondrial dysfunction and an increase in myostatin expression. Currently, the use of nutritional interventions such as late-evening snacks, branched-chain amino acid supplementation, and physical activity have been proposed to help the management and treatment of sarcopenia. However, little evidence exists to comprehensively support their use in clinical settings. Several new pharmacological strategies, including myostatin inhibition and the nutraceutical Urolithin A, have recently been proposed to treat age-related sarcopenia and may also be of use in CLD. This review highlights the potential molecular mechanisms contributing to sarcopenia in CLD alongside a discussion of existing and potential new treatment strategies.

Compound Sarcopenia in Hospitalized Patients with Cirrhosis Worsens Outcomes with Increasing Age

Background: There are limited data on outcomes of older patients with chronic diseases. Skeletal muscle loss of aging (primary sarcopenia) has been extensively studied but the impact of secondary sarcopenia of chronic disease is not as well evaluated. Older patients with chronic diseases have both primary and secondary sarcopenia that we term compound sarcopenia. We evaluated the clinical impact of compound sarcopenia in hospitalized patients with cirrhosis given the increasing number of patients and high prevalence of sarcopenia in these patients. Design: The Nationwide Inpatients Sample (NIS) database (years 2010–2014) was analyzed to study older patients with cirrhosis. Since there is no universal hospital diagnosis code for “muscle loss”, we used a comprehensive array of codes for “muscle loss phenotype” in the international classification of diseases-9 (ICD-9). A randomly selected 2% sample of hospitalized general medical population (GMP) and inpatients with cirrhosis were stratified into 3 age groups based on age-related changes in muscle mass. In-hospital mortality, length of stay (LoS), cost of hospitalization (CoH), comorbidities and discharge disposition were analyzed. Results. Of 517,605 hospitalizations for GMP and 106,835 hospitalizations for treatment of cirrhosis or a cirrhosis-related complication, 207,266 (40.4%) GMP and 29,018 (27.7%) patients with cirrhosis were >65 years old, respectively. Muscle loss phenotype in both GMP and inpatients with cirrhosis 51–65 years old and >65 years old was significantly (p < 0.001 for all) associated with higher mortality, LoS, and CoH compared to those ≤50 years old. Patients >65 years old with cirrhosis and muscle loss phenotype had higher mortality (adjusted OR: 1.06, 95% CI [1.04, 1.08] and CoH (adjusted odds ratio (OR): 1.10, 95% confidence interval (CI) [1.04, 1.08])) when compared to >65 years old GMP with muscle loss phenotype. Muscle loss in younger patients with cirrhosis (≤50 years old) was associated with worse outcomes compared to GMP >65 years old. Non-home discharges (nursing, skilled, long-term care) were more frequent with increasing age to a greater extent in patients with cirrhosis with muscle loss phenotype for each age stratum. Conclusion: Muscle loss is more frequent in older patients with cirrhosis than younger patients with cirrhosis and older GMP. Younger patients with cirrhosis had clinical outcomes similar to those of older GMP, suggesting an accelerated senescence in cirrhosis. Compound sarcopenia in older patients with cirrhosis is associated with higher inpatient mortality, increased LoS, and CoH compared to GMP with sarcopenia.

The effect of malnutrition on the infectious outcomes of hospitalized patients with cirrhosis: analysis of the 2011-2017 hospital data

BACKGROUND

In patients with cirrhosis, there is a clinical concern that the development of protein-calorie malnutrition will affect the immune system and predispose these patients to increased infectious outcomes.

AIMS

In this study, we evaluate the effects of malnutrition on the infectious outcomes of patients admitted with cirrhosis.

MATERIALS AND METHODS

This study used the 2011-2017 National Inpatient Sample to identify patients with cirrhosis. These patients were stratified using malnutrition (protein-calorie malnutrition, cachexia, and sarcopenia) and matched using age, gender, and race with 1:1 nearest neighbor matching method. The endpoints included mortality and infectious outcomes.

RESULTS

After matching, there were 96 842 malnutrition-present cohort and equal number of controls. In univariate analysis, the malnutrition cohort had higher hospital mortality [10.40 vs. 5.04% P < 0.01, odds ratio (OR) 2.18, 95% confidence interval (CI) 2.11-2.26]. In multivariate models, malnutrition was associated with increased mortality [P < 0.01, adjusted odds ratio (aOR) 1.32, 95% CI 1.27-1.37] and infectious outcomes, including sepsis (P < 0.01, aOR 1.94, 95% CI 1.89-2.00), pneumonia (P < 0.01, aOR 1.68, 95% CI 1.63-1.73), UTI (P < 0.01, aOR 1.39, 95% CI 1.35-1.43), cellulitis (P < 0.01, aOR 1.09, 95% CI 1.05-1.13), cholangitis (P < 0.01, aOR 1.39, 95% CI 1.26-1.55), and clostridium difficile (P < 0.01, aOR 2.11, 95% CI 1.92-2.31).

CONCLUSION

The results of this study indicate that malnutrition is an independent risk factor of hospital mortality and local/systemic infections in patients admitted with cirrhosis.

Nutraceuticals for the treatment of sarcopenia in chronic liver disease

BACKGROUND AND AIMS

Sarcopenia, defined as loss of muscle mass, strength and function, is associated with adverse clinical outcomes in patients with cirrhosis. Despite improved understanding of the multifaceted pathogenesis, there are few established therapies to treat or prevent muscle loss in this population. This narrative review examines the available literature investigating the role of nutraceuticals for the prevention or treatment of muscle wasting in chronic liver disease.

METHODS

A comprehensive search or Medline and PubMED databases was conducted. Reference lists were screened to identify additional articles.

RESULTS

A number of nutritional supplements and vitamins target the specific metabolic derangements that contribute to sarcopenia in cirrhosis including altered amino acid metabolism, hyperammonaemia and inflammation. Branched chain amino acid (BCAA) supplementation has proposed anabolic effects through dual pathways of enhanced ammonia clearance and stimulation of muscle protein synthesis. l-carnitine also has multimodal effects on muscle and shows promise as a therapy for muscle loss through anti-inflammatory, antioxidant and ammonia lowering properties. Other nutraceuticals including l-ornithine l-aspartate, omega-3 polyunsaturated fatty acids and zinc and vitamin D supplementation, may similarly have positive effects on muscle homeostasis, however further evidence to support their use in cirrhotic populations is required.

CONCLUSION

Nutraceuticals offer a promising and likely safe adjunct to standard care for sarcopenia in cirrhosis. While there is most evidence to support the use of BCAA and l-carnitine supplementation, further well-designed clinical trials are needed to elucidate their efficacy as a therapy for muscle loss in this population.

Radiologic Definition of Sarcopenia in Chronic Liver Disease

Sarcopenia is prevalent in patients with chronic liver disease, and affected patients tend to have worse clinical outcomes and higher mortality. However, relevant analyses are limited by heterogeneity in the definition of sarcopenia and in the methodological approaches in assessing it. We reviewed several radiologic methods for sarcopenia in patients with chronic liver disease. Dual energy X-ray absorptiometry (DXA) can measure muscle mass, but it is difficult to evaluate muscle quality using this technique. Computed tomography, known as the gold standard for diagnosing sarcopenia, enables the objective measurement of muscle quantity and quality. The third lumbar skeletal muscle index (L3 SMI) more accurately predicted the mortality of subjects than the psoas muscle index (PMI). Few studies have evaluated the sarcopenia of chronic liver disease using ultrasonography and magnetic resonance imaging, and more studies are needed. Unification of the measurement method and cut-off value would facilitate a more systematic and universal prognosis evaluation in patients with chronic liver disease.

Radiologic Definition of Sarcopenia in Chronic Liver Disease

Sarcopenia is prevalent in patients with chronic liver disease, and affected patients tend to have worse clinical outcomes and higher mortality. However, relevant analyses are limited by heterogeneity in the definition of sarcopenia and in the methodological approaches in assessing it. We reviewed several radiologic methods for sarcopenia in patients with chronic liver disease. Dual energy X-ray absorptiometry (DXA) can measure muscle mass, but it is difficult to evaluate muscle quality using this technique. Computed tomography, known as the gold standard for diagnosing sarcopenia, enables the objective measurement of muscle quantity and quality. The third lumbar skeletal muscle index (L3 SMI) more accurately predicted the mortality of subjects than the psoas muscle index (PMI). Few studies have evaluated the sarcopenia of chronic liver disease using ultrasonography and magnetic resonance imaging, and more studies are needed. Unification of the measurement method and cut-off value would facilitate a more systematic and universal prognosis evaluation in patients with chronic liver disease.

Nutrition in Chronic Liver Disease: Consensus Statement of the Indian National Association for Study of the Liver

Malnutrition and sarcopenia are common in patients with chronic liver disease and are associated with increased risk of decompensation, infections, wait-list mortality and poorer outcomes after liver transplantation. Assessment of nutritional status and management of malnutrition are therefore essential to improve outcomes in patients with chronic liver disease. This consensus statement of the Indian National Association for Study of the Liver provides a comprehensive review of nutrition in chronic liver disease and gives recommendations for nutritional screening and treatment in specific clinical scenarios of malnutrition in cirrhosis in adults as well as children with chronic liver disease and metabolic disorders.

The inter- and intrarater reliability and feasibility of dietetic assessment of sarcopenia and frailty in potential liver transplant recipients: A mixed-methods study

Sarcopenia and frailty are associated with poorer outcomes in potential liver transplant (LT) recipients. We examined the reliability and feasibility of dietitians assessing sarcopenia and frailty. Seventy-five adults referred for LT underwent assessments of muscle mass (abdominal CTs), physical function (handgrip strength; HGS, short physical performance battery; SPPB), and frailty (Liver Frailty Index; LFI). Inter- and intrarater reliability and agreement were assessed in subsets of patients using intraclass correlation coefficients (ICCs) and Bland-Altman plots. CTs were analyzed by a dietitian and two independent experts, two dietitians assessed function and frailty. Feasibility assessed system, patient, and profession factors (staff survey). Inter- and intrarater reliability for CT-defined low muscle were excellent (ICCs > 0.97). Reliability between dietitians was excellent for HGS (0.968, 95% CI, 0.928-0.986), SPPB (0.932, 95% CI, 0.798-0.973), and LFI (0.938, 95% CI 0.861-0.973). Bland-Altman analysis indicated excellent agreement for HGS. All transplant clinicians valued sarcopenia and frailty in LT assessments and considered the dietitian appropriate to perform them. Seven saw no barriers to implementation into practice, while five queried test standardization, learning from repeat testing, and resource cost. Dietetic assessments of sarcopenia and frailty are reliable, feasible, and valued measures in the assessment of potential LT recipients.

New anthropometric and biochemical models for estimating appendicular skeletal muscle mass in male patients with cirrhosis

OBJECTIVES

The use of easily accessible methods to estimate skeletal muscle mass (SMM) in patients with cirrhosis is often limited by the presence of edema and ascites, precluding a reliable diagnosis of sarcopenia. The aim of this study was to design predictive models using variables derived from anthropometric and/or biochemical measures to estimate SMM; and to validate their applicability in diagnosing sarcopenia in patients with cirrhosis.

METHODS

Anthropometric and biochemical data were obtained from 124 male patients (18-76 y of age) with cirrhosis who also underwent dual-energy x-ray absorptiometry (DXA) and handgrip strength (HGS) assessments to identify low SMM and diagnose sarcopenia using reference cutoff values. Univariate analyses for variable selection were applied to generate predictive decision tree models for low SMM. Model accuracy for the prediction of low SMM and sarcopenia (when associated with HGS) was tested by comparison with reference cutoff values (appendicular SMM index, obtained by DXA) and clinical sarcopenia diagnoses. The prognostic value of the models for the prediction of sarcopenia and mortality at 104 wk of follow up was further tested using Kaplan-Meier graphics and Cox models.

RESULTS

The models with anthropometric variables, alone and combined with biochemical variables, showed good accuracy (0.89 [0.83; 0.94] and 0.90 [0.84; 0.95], respectively) and sensitivity (0.72 [0.56; 0.85] and 0.74 [0.59; 0.86], respectively) and excellent specificity (0.96 [0.90; 0.99] and 0.97 [0.92; 0.99], respectively) in predicting SMM. Both models showed excellent accuracy (0.94 [0.89; 0.98], good sensitivity (0.68 [0.45; 0.86]), and excellent specificity (1.00 [0.96; 1.00]) in predicting sarcopenia. The models predicted mortality in patients with sarcopenia, with the likelihood of death sixfold greater relative to patients not predicted to have sarcopenia.

CONCLUSIONS

Our simple and inexpensive models provided a practical and safe approach to diagnosing sarcopenia patients with cirrhosis along with an estimate of their mortality risk when other reference methods are unavailable.