The Long Winding Road to Transplant: How Sarcopenia and Debility Impact Morbidity and Mortality on the Waitlist

Comparing the performance of 3 sarcopenia definitions for predicting adverse events prior to liver transplant

BACKGROUND

Sarcopenia is a syndrome of severe muscle wasting, associated with adverse outcomes related to liver transplantation (LT). There are several approaches used to identify sarcopenia. We aimed to investigate the prevalence of sarcopenia using 3 different criteria and determine how these performed in relation to clinical outcomes.

METHODS

The cohort study included 237 adults with cirrhosis referred for LT. Sarcopenia was identified using (1) CT-defined; and the (2) original and (3) updated European Working Group on Sarcopenia in Older People criteria (EWGSOP1 and 2). Logistic regression was used to estimate OR and 95% CI for the relationships between sarcopenia and receiving an LT, unplanned admissions pre-LT, surgical complications, and length of stay for the LT admission. Fine-Gray competing risk analysis explored the impact of sarcopenia on receiving an LT and unplanned admissions. The AUC determined the predictive utility of the criteria.

RESULTS

The prevalence of CT-defined sarcopenia (52%) was more than twice and 4-fold that of EWGSOP1-defined (22%) and EWGSOP2-defined (11%) sarcopenia, respectively. No criteria demonstrated a significant association with time to LT nor the time to unplanned admissions pre-LT. Similarly, none of the 3 criteria had superior predictive utility for the clinical outcomes for unplanned hospital admissions pre-LT of receiving an LT, with all 3 criteria having identical moderate AUCs for unplanned admissions (0.70) and similar weak AUCs (≤0.55) for the likelihood of receiving an LT.

CONCLUSIONS

Sarcopenia in patients undergoing LT evaluation is prevalent. EWGSOP criteria appear to offer no advantage over CT-only criteria in identifying patients at increased risk of adverse LT outcomes. Bedside measures of muscle function may be of benefit in tracking the effectiveness of interventions targeting sarcopenia.

Cardiorespiratory Fitness From Cardiopulmonary Exercise Testing Is a Comprehensive Risk-stratifying Tool in Liver Transplant Candidates

Background

Cardiovascular disease and physical decline are prevalent and associated with morbidity/mortality in liver transplant (LT) patients. Cardiopulmonary exercise testing (CPX) provides comprehensive cardiopulmonary and exercise response assessments. We investigated cardiorespiratory fitness (CRF) and cardiac stress generated during CPX in LT candidates.

Methods

LT candidates at 2 centers underwent CPX. Standard-of-care cardiac stress testing (dobutamine stress echocardiography, DSE) results were recorded. Physical function was assessed with liver frailty index and 6-min walk test. CPX/DSE double products were calculated to quantify cardiac stress. To better study the association of CPX-derived metrics with physical function, the cohort was divided into 2 groups based on 6-min walk test median (372 m).

Results

Fifty-four participants (62 ± 8 y; 65% men, Model for End-Stage Liver Disease-Na 14 [10-18]) underwent CPX. Peak oxygen consumption was 14.1 mL/kg/min for an anerobic threshold of 10.2 mL/kg/min, with further CRF decline in the lower 6MWT cohort despite lack of liver frailty index-frailty in 90%. DSE was nondiagnostic in 18% versus 4% of CPX (P = 0.058). All CPX were negative for ischemia. A double product of ≥25 000 was observed in 32% of CPX and 11% of DSE (P = 0.020). Respiratory function testing was normal. No patient presented major cardiovascular events at 30 d post-LT.

Conclusions

CPX provided efficient and effective combined cardiopulmonary risk and frailty assessments of LT candidates in a 1-stop test. The CRF was found to be very low despite preserved physical function or lack of frailty.

The relationship between imaging-based body composition abnormalities and long-term mortality in patients with liver cirrhosis

BACKGROUND

Emerging evidence on cirrhosis suggests a close correlation between abnormality in body composition characteristics and poor prognosis. This study aimed to evaluate the impact of dynamic changes in body composition on the prognostic outcomes in patients with cirrhosis.

METHODS

This retrospective analysis included 158 patients diagnosed as cirrhosis from January 2018 to August 2023. Skeletal muscle mass, muscle quality, visceral and subcutaneous adiposity were evaluated using computed tomography (CT) imaging at the third lumbar vertebra level. Competing risk model was performed four different body composition status (i.e., normal, only sarcopenia, only myosteatosis, and combined status) for liver-related mortality. We also explored the relationship between the dynamic change in body composition and long-term prognosis by applying Gray's test.

RESULTS

Of the 158 cirrhotic patients (mean [SD] age, 57.1 [12.6] years), sarcopenia was present in 85 (60.1 %) patients, while 22 (13.9 %) patients had sarcopenic obesity and 68 (43.0 %) had myosteatosis. Patients solely diagnosed with sarcopenia exhibited a higher mortality rate compared to those with normal body composition (Gray's test, P=0.006), while patients solely diagnosed with myosteatosis or with a combination of sarcopenia and myosteatosis did not reach statistical significance (Gray's test, P=0.076; P=0.140). Multivariable analysis also revealed that VSR (HR=1.10 [1.01∼1.20]; P=0.028), sarcopenia (HR=2.73 [1.20∼6.22], P=0.017) and myosteatosis (HR=2.39 [1.10∼5.18], P=0.028) were significant independent predictors of liver-related deaths. Otherwise, patients exhibiting aggravating body composition during follow-up period were associated with a significantly higher mortality risk compared to those with normal or remission body composition status (HR=7.63 [1.12∼51.14]; P=0.036).

CONCLUSION

Progressive alterations in body composition status appears to be associated with liver-related mortality in individuals with liver cirrhosis. Focusing on the management of skeletal muscle, along with visceral and subcutaneous adiposity, may contribute to improving the prognosis of cirrhotic patients.

Continuous home terlipressin infusion increases handgrip strength and reduces ascites-A prospective randomized crossover study

BACKGROUND AND AIMS

Observational studies suggest a beneficial effect of continuous terlipressin infusion (CTI) on ascites and sarcopenia in decompensated cirrhosis with portal hypertension.

APPROACH AND RESULTS

This single-center, prospective, cross-over study randomized 30 patients with cirrhosis, ascites, and sarcopenia to commence on 12 weeks of home CTI or 12 weeks of observation prior to cross-over. The co-primary outcomes were change in handgrip strength and paracentesis volume. Secondary outcomes included quality of life, sarcopenia measures, renal function, safety, and hospitalization. The median age of participants was 62 years (IQR: 57-64), the median Model for End-Stage Liver Disease-Sodium was 16 (12.3-20.8), and 22 (73%) were male. Handgrip strength increased by a mean adjusted difference (MAD) of 3.09 kg (95% CI: 1.11-5.08 kg) between CTI and observation ( p =0.006); an 11.8% increase from baseline. The total volume of ascites drained decreased by a MAD of 11.39L (2.99-19.85, p =0.01), with 1.75 fewer episodes of paracentesis (0.925-2.59, p <0.001) on CTI. Serum creatinine decreased, urinary sodium excretion increased, and quality of life was significantly higher on CTI (all p <0.001), with an increase in Chronic Liver Disease Questionnaire score of 0.41 points (0.23-0.59). There were 7 minor line-related complications but no cardiac events or pulmonary edema.

CONCLUSIONS

This novel study demonstrates a significant increase in handgrip strength, reduction in paracentesis volume, and improved quality of life in patients with decompensated cirrhosis treated with continuous terlipressin infusion. These findings provide a strong rationale for the use of ambulatory CTI in appropriately selected patients with cirrhosis.

Systemic impacts of metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction-associated steatohepatitis (MASH) on heart, muscle, and kidney related diseases

Metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as non-alcoholic fatty liver disease (NAFLD), is the most common liver disorder worldwide, with an estimated global prevalence of more than 31%. Metabolic dysfunction-associated steatohepatitis (MASH), formerly known as non-alcoholic steatohepatitis (NASH), is a progressive form of MASLD characterized by hepatic steatosis, inflammation, and fibrosis. This review aims to provide a comprehensive analysis of the extrahepatic manifestations of MASH, focusing on chronic diseases related to the cardiovascular, muscular, and renal systems. A systematic review of published studies and literature was conducted to summarize the findings related to the systemic impacts of MASLD and MASH. The review focused on the association of MASLD and MASH with metabolic comorbidities, cardiovascular mortality, sarcopenia, and chronic kidney disease. Mechanistic insights into the concept of lipotoxic inflammatory "spill over" from the MASH-affected liver were also explored. MASLD and MASH are highly associated (50%-80%) with other metabolic comorbidities such as impaired insulin response, type 2 diabetes, dyslipidemia, hypertriglyceridemia, and hypertension. Furthermore, more than 90% of obese patients with type 2 diabetes have MASH. Data suggest that in middle-aged individuals (especially those aged 45-54), MASLD is an independent risk factor for cardiovascular mortality, sarcopenia, and chronic kidney disease. The concept of lipotoxic inflammatory "spill over" from the MASH-affected liver plays a crucial role in mediating the systemic pathological effects observed. Understanding the multifaceted impact of MASH on the heart, muscle, and kidney is crucial for early detection and risk stratification. This knowledge is also timely for implementing comprehensive disease management strategies addressing multi-organ involvement in MASH pathogenesis.

Validation of the Minnesota Pectoralis Risk Score to predict mortality in the HeartMate 3 population

BACKGROUND

The Minnesota Pectoralis Risk Score (MPRS) utilizes computed tomography-quantified thoracic muscle and clinical variables to predict survival after left ventricular assist device (LVAD) implantation. The model has not been prospectively tested in HeartMate 3 recipients.

METHODS

A single-center HeartMate 3 cohort from July 2016 to July 2021 (n = 108) was utilized for this analysis. Cohort subjects with complete covariates for MPRS calculation (pectoralis muscle measures, Black race, creatinine, total bilirubin, body mass index, bridge to transplant status, and presence/absence of contrast) implanted after MPRS development were included. MPRS were calculated on each subject. Receiver operating characteristic curves were generated to test model discrimination at 30-day, 90-day, and 1-year mortality post-LVAD. Next, the performance of the 1-year post-LVAD outcome was compared to the HeartMate 3 survival risk score (HM3RS).

RESULTS

The mean age was 58 (15 years), 80% (86/108) were male, and 26% (28/108) were destination therapy. The area under the curve (AUC) for the MPRS model to predict post-LVAD mortality was 0.73 at 30 days, 0.78 at 90 days, and 0.81 at 1 year. The AUC for the HM3RS for the 1-year outcome was 0.693. Each 1-unit point of the MPRS was associated with a significant increase in the hazard rate of death after LVAD (hazard ratio 2.1, 95% confidence interval 1.5-3.0, p < 0.0001).

CONCLUSIONS

The MPRS had high performance in this prospective validation, particularly with respect to 90-day and 1-year post-LVAD mortality. Such a tool can provide additional information regarding risk stratification to aid informed decision-making.

Nutrition support management of organ transplant recipients in the acute posttransplant phase

Patients who undergo solid organ transplant can have an extensive and challenging postoperative course. The chronicity of the disease state prior to transplant in combination with transplant-specific complications and immunosuppressant medications can lead to distinct challenges that are not observed in other critically ill patients. Although the manifestation of posttransplant complications may be specific to the organ being transplanted, there are common transplant challenges that affect nutrition therapy in these patients. Effects of malnutrition, metabolic aberrations, and posttransplant organ dysfunction should be considered when developing a nutrition care plan for patients in the immediate posttransplant phase. This article addresses the various complications that can arise in the immediate posttransplant phase among patients undergoing solid organ transplant and the appropriate nutrition interventions or considerations for this specialized patient population.

'Effects of a home-based bimodal lifestyle intervention in frail patients with end-stage liver disease awaiting orthotopic liver transplantation': study protocol of a non-randomised clinical trial

INTRODUCTION

Patients with end-stage liver disease awaiting orthotopic liver transplantation (OLT) are generally classified as frail due to disease-related malnutrition and a progressive decline in musculoskeletal and aerobic fitness, which is associated with poor pre-OLT, peri-OLT and post-OLT outcomes. However, frailty in these patients may be reversable with adequate exercise and nutritional interventions.

METHODS AND ANALYSIS

Non-randomised clinical trial evaluating the effect of a home-based bimodal lifestyle programme in unfit patients with a preoperative oxygen uptake (VO2) at the ventilatory anaerobic threshold ≤13 mL/kg/min and/or VO2 at peak exercise ≤18 mL/kg/min listed for OLT at the University Medical Center Groningen (UMCG). The programme is patient tailored and comprises high-intensity interval and endurance training, and functional exercises three times per week, combined with nutritional support. Patients will go through two training periods, each lasting 6 weeks.The primary outcome of this study is the impact of the programme on patients' aerobic fitness after the first study period. Secondary outcomes include aerobic capacity after the second study period, changes in sarcopenia, anthropometry, functional mobility, perceived quality of life and fatigue, incidence of hepatic encephalopathy and microbiome composition. Moreover, number and reasons of intercurrent hospitalisations during the study and postoperative outcomes up to 12 months post OLT will be recorded. Finally, feasibility of the programme will be assessed by monitoring the participation rate and reasons for non-participation, number and severity of adverse events, and dropout rate and reasons for dropout.

ETHICS AND DISSEMINATION

This study was approved by the Medical Research Ethics Committee of the UMCG (registration number NL83612.042.23, August 2023) and is registered in the Clinicaltrials.gov register (NCT05853484). Good Clinical Practice guidelines and the principles of the Declaration of Helsinki will be applied. Results of this study will be submitted for presentation at (inter)national congresses and publication in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT05853484.

The aspartate aminotransferase to alanine aminotransferase ratio: A novel indicator for skeletal muscle mass in Chinese community adults

OBJECTIVES

The aspartate aminotransferase to alanine aminotransferase (AST/ALT) ratio, an indicator for liver fibrosis, could be easily detected in clinical practice. The aim of this study was to examine the association between the AST/ALT ratio and skeletal muscle mass among Chinese community adult residents.

METHODS

We enrolled 2644 participants, age ≥18 y, undergoing bioelectrical impedance analysis and liver function test. Univariate and multivariate logistic regression models were used to analyze the effect of the AST/ALT ratio on the presence of low muscle mass (LMM). Multiple linear regression analysis was used to assess the factors associated with the skeletal muscle mass index (SMI) and to construct a formula to calculate the SMI.

RESULTS

When the AST/ALT ratio was regarded as a categorical variable, AST/ALT quartiles 9-2.19) kept independent effects on the presence of LMM status. When it was regarded as a continuous variable, each unit of the AST/ALT ratio was significantly associated with a 49% (P < 0.01) augment of the prevalence of LMM. By multiple general linear regression analysis, the formula was constructed with an adjusted R2 of 0.72: SMI (kg/m2) = -0.14 AST/ALT ratio + 1.35 sex (male: 1; female: 0) + 0.72 overweight status (yes: 1; no: 0) - 0.14 age (≤65: 0; >65: 1) + 6.26.

CONCLUSION

In general, the high AST/ALT ratio was an independent adverse indicator of the presence of LMM.

What Does Sarcopenia Have to Do with Nonalcoholic Fatty Liver Disease?

Nonalcoholic fatty liver disease (NAFLD) is one of the most common causes of chronic liver disease. As the second stage of developing steatosis, nonalcoholic hepatitis (NASH) carries the risk of fibrosis, cirrhosis, and hepatocellular carcinoma. Sarcopenia is defined as a condition characterized by a decrease in muscle mass and functional decline. Both NAFLD and sarcopenia are global problems. The pathophysiological mechanisms that link the two entities of the disease are insulin resistance, inflammation, nutritional deficiencies, impairment of myostatin and adiponectin, or physical inactivity. Furthermore, disorders of the gut-liver axis appear to induce the process of developing NAFLD and sarcopenia. The correlations between NAFLD and sarcopenia appear to be bidirectional, so the main objective of the review was to determine the cause-and-effect relationship between the two diseases.

Frailty and sarcopenia: A bibliometric analysis of their association and potential targets for intervention

Frailty and sarcopenia are age-related diseases, and exhibit a concomitant relationship, as they share many common clinical features and etiological factors. Transitions within frailty status would be influenced by the presence of sarcopenia. Investigating their association to devise efficacious intervention and management strategies for geriatric patients is imperative, given their potentially unfavorable outcomes. In this study, the literature on sarcopenia and frailty was screened in the Web of Science core collection database over the past 30 years to ascertain the link between them through bibliometric analysis and the exploration of disease-related molecular pathways within the GeneCards and OMIM databases was conducted. Per inclusion and exclusion criteria, 3889 literature sources were selected for subsequent analysis. Keywords, including "cirrhosis" and "postoperative complications," represent the current and potential future research trends and focal points in this field. Moreover, 63 common potential targets between the two diseases were identified. Their pathogenesis involved cellular aging and endocrine metabolism regulation pathways, including AMPK, cell senescence, and the endocrine resistance pathway. This study identified an intimate correlation between frailty and sarcopenia in pathogenesis, prevention, and treatment measures, establishing a foundation for exploring shared prevention and treatment strategies for these two disorders.

Associations of Skeletal Muscle Mass, Muscle Fat Infiltration, Mitochondrial Energetics, and Cardiorespiratory Fitness with Liver Fat Among Older Adults

Background

Muscle mass loss may be associated with liver fat accumulation, yet scientific consensus is lacking and evidence in older adults is scant. It is unclear which muscle characteristics might contribute to this association in older adults.

Methods

We associated comprehensive muscle-related phenotypes including muscle mass normalized to body weight (D 3 -creatine dilution), muscle fat infiltration (MRI), carbohydrate-supported muscle mitochondrial maximal oxidative phosphorylation (respirometry), and cardiorespiratory fitness (VO 2 peak) with liver fat among older adults. Linear regression models adjusted for age, gender, technician (respirometry only), daily minutes of moderate to vigorous physical activity, and prediabetes/diabetes status tested main effects and interactions of each independent variable with waist circumference (high: women-≥88 cm, men-≥102 cm) and gender.

Results

Among older adults aged 75 (IQR 73, 79 years; 59.8% women), muscle mass and liver fat were not associated overall but were positively associated among participants with a high waist circumference (β: 25.2; 95%CI 11.7, 40.4; p =.0002; N=362). Muscle fat infiltration and liver fat were positively associated (β: 15.2; 95%CI 6.8, 24.3; p =.0003; N=378). Carbohydrate-supported maximum oxidative phosphorylation and VO 2 peak (adjusted β: -12.9; 95%CI -20.3, -4.8; p =0.003; N=361) were inversely associated with liver fat; adjustment attenuated the estimate for maximum oxidative phosphorylation although the point estimate remained negative (β: -4.0; 95%CI -11.6, 4.2; p =0.32; N=321).

Conclusions

Skeletal muscle-related characteristics are metabolically relevant factors linked to liver fat in older adults. Future research should confirm our results to determine whether trials targeting mechanisms common to liver and muscle fat accumulation are warranted.

Nutritional Support for Liver Diseases

The liver is a key organ that is responsible for the metabolism of proteins, fats, and carbohydrates and the absorption and storage of micronutrients. Unfortunately, the prevalence of chronic liver diseases at various stages of advancement in the world population is significant. Due to the physiological function of the liver, its dysfunction can lead to malnutrition and sarcopenia, and the patient's nutritional status is an important prognostic factor. This review discusses key issues related to the diet therapy of patients with chronic liver diseases, as well as those qualified for liver transplantation and in the postoperative period.

Low back pain in patients hospitalised with liver cirrhosis- a retrospective study

BACKGROUND

Lower back pain is a common issue, but little is known about the prevalence of pain in patients with liver cirrhosis during hospitalisation. Therefore, the objective of this study was to determine lower back pain in patients with liver cirrhosis.

METHODS

The sample consisted of patients with liver cirrhosis (n = 79; men n = 55; women n = 24; mean age = 55.79 ± 12.52 years). The hospitalised patients were mobile. The presence and intensity of pain were assessed in the lumbar spine during hospitalisation. The presence of pain was assessed using the visual analogue pain scale (0-10). The range of motion of the lower spine was assessed using the Schober and Stibor tests. Frailty was measured by Liver Frailty Index (LFI). The condition of liver disease was evaluated using The Model For the End-Stage Liver Disease (MELD) and Child-Pugh score (CPS) and ascites classification. Student's t test and Mann-Whitney test were used for analysis of the difference of group. Analysis of variance (ANOVA) with the Tukey post hoc test was used to test differences between categories of liver frailty index. The Kruskal-Wallis test was used to test pain distribution. Statistical significance was determined at the α-0.05 significance level.

RESULT

The prevalence of pain in patients with liver cirrhosis was 13.92% (n = 11), and the mean intensity of pain according to the visual analogue scale was 3.73 (± 1.90). Lower back pain was present in patients with ascites (15.91%; n = 7) and without ascites (11.43%; n = 4). The prevalence of lower back pain was not statistically significant between patients with and without ascites (p = 0,426). The base of Schober's assessment mean score was 3.74 cm (± 1.81), and based on Stibor's assessment mean score was 5.84 cm (± 2.23).

CONCLUSION

Lower back pain in patients with liver cirrhosis is a problem that requires attention. Restricted spinal mobility has been reported in patients with back pain, according to Stibor, compared to patients without pain. There was no difference in the incidence of pain in patients with and without ascites.

Review of Sarcopenia and Testosterone Deficiency With Chronic Liver Disease and Postoperative Liver Transplant Utility of Short-Term Testosterone Replacement Therapy

OBJECTIVES

Chronic liver disease is often associated with testosterone deficiency. However, testosterone replacement does not improve hepatic function or survival with diseased liver. So far, to our knowledge, testosterone replacement therapy after successful livertransplantforfunctional sarcopenia has not been studied. We had 3 goals: (1) define postoperative functional sarcopenia afterlivertransplant with serum testosterone level; (2) examine the role of short-term testosterone replacement therapy with active in-bed exercise of upper and lower extremity joints; and (3) correlate functional sarcopenia with skeletal muscle index and skeletal muscle density in relation to ascites, pleural effusion subtracted body mass index.

MATERIALS AND METHODS

We evaluated 16 liver transplant recipients who had been receiving posttransplanttestosterone replacementtherapy with functional sarcopenia. Preoperative and postoperative demographics and laboratory and radiological data were retrieved; body mass index, skeletal muscle index, and skeletal muscle density were calculated. For this retrospective study, institutional review board approval was obtained before the electronic database was reviewed and analyzed.

RESULTS

Mean testosterone level was 28.3 ng/dL (<5% of expected). Twelve patients received 1 dose, and the remaining 4 patients received >1 dose oftestosterone cypionate, 200 mg. Mean hospital stay was 26 days. Seven patients were discharged home, with the remaining patients to a rehabilitation facility or nursing home. One patient died from a cardiac event, and another patient died from recurrent metastatic malignancy. The 1-year and 5-year actuarial patient and graft survival rates were 93.8% and 87.5%, respectively. Overall, 5 patients were sarcopenic by skeletal muscle index, and 6 patients had poor muscle quality by skeletal muscle density.

CONCLUSIONS

Testosterone deficiency after liver transplant exists with functional sarcopenia. Two- thirds of such recipients have low skeletal muscle index and/or have low skeletal muscle density. Short- term testosterone replacement therapy with in-bed active exercise provides 5-year patient and graft survival of 87.5%.

Muscle strength, but not body mass index, is associated with mortality in patients with non-alcoholic fatty liver disease

BACKGROUND

Whether adiposity and muscle function are associated with mortality risk in patients with non-alcoholic fatty liver disease (NAFLD) remains unknown. We examine the independent and combined associations of body mass index (BMI) and muscle strength with overall mortality in individuals with NAFLD.

METHODS

We analysed data from 7083 participants with NAFLD in the Thai National Health Examination Survey and their linked mortality. NAFLD was defined using a lipid accumulation product in participants without significant alcohol intake. Poor muscle strength was defined by handgrip strength of <28 kg for men and <18 kg for women, according to the Asian Working Group on Sarcopenia. The Cox proportional-hazards model was constructed to estimate the adjusted hazard ratio (aHR) for overall mortality.

RESULTS

The mean age was 49.3 ± 13.2 years, and 69.4% of subjects were women. According to the Asian-specific criteria, 1276 individuals (18.0%) were classified as lean NAFLD (BMI 18.5-22.9 kg/m2 ), 1465 (20.7%) were overweight NAFLD (BMI 23-24.9 kg/m2 ), and 4342 (61.3%) were obese NAFLD (BMI ≥ 25 kg/m2 ). Over 60 432 person-years, 843 participants died. In Cox models adjusted for physiologic, lifestyle, and comorbid factors, individuals with lean NAFLD [aHR 1.18, 95% confidence interval (CI): 0.95-1.48; P = 0.138] and subjects with overweight NAFLD (aHR 1.28, 95% CI: 0.89-1.84; P = 0.158) had mortality risk estimates similar to their obese counterparts, whereas participants with lower handgrip strength had significantly higher mortality risk than those with higher handgrip strength in men and women. Compared with obese individuals with the highest handgrip strength, elevated mortality risk was observed among men (aHR 3.21, 95% CI: 1.35-7.62, P = 0.011) and women (aHR 2.22, 95% CI, 1.25-3.93, P = 0.009) with poor muscle strength. Among men, poor muscle strength was associated with increased risk of mortality with obese NAFLD (aHR 3.94, 95% CI, 1.38-11.3, P = 0.013), overweight NAFLD (aHR 2.93, 95% CI, 1.19-7.19, P = 0.021), and lean NAFLD (aHR 2.78, 95% CI, 0.93-8.32, P = 0.065). Among women, poor muscle strength was associated with increased mortality risk with obese NAFLD (aHR 2.25, 95% CI, 1.06-4.76, P = 0.036), overweight NAFLD (aHR 1.69, 95% CI, 0.81-3.51, P = 0.153), and lean NAFLD (aHR 2.47, 95% CI, 1.06-5.73, P = 0.037).

CONCLUSIONS

In this nationwide cohort of individuals with NAFLD, muscle strength, but not BMI, was independently associated with long-term overall mortality. Measuring handgrip strength can be a simple, non-invasive risk stratification approach for overall mortality in patients with NAFLD.

The Effect of Diet and Exercise Interventions on Body Composition in Liver Cirrhosis: A Systematic Review

Alterations in body composition, in particular sarcopenia and sarcopenic obesity, are complications of liver cirrhosis associated with adverse outcomes. This systematic review aimed to evaluate the effect of diet and/or exercise interventions on body composition (muscle or fat) in adults with cirrhosis. Five databases were searched from inception to November 2021. Controlled trials of diet and/or exercise reporting at least one body composition measure were included. Single-arm interventions were included if guideline-recommended measures were used (computed tomography/magnetic resonance imaging, dual-energy X-ray absorptiometry, bioelectrical impedance analysis, or ultrasound). A total of 22 controlled trials and 5 single-arm interventions were included. Study quality varied (moderate to high risk of bias), mainly due to lack of blinding. Generally, sample sizes were small (n = 6–120). Only one study targeted weight loss in an overweight population. When guideline-recommended measures of body composition were used, the largest improvements occurred with combined diet and exercise interventions. These mostly employed high protein diets with aerobic and or resistance exercises for at least 8 weeks. Benefits were also observed with supplementary branched-chain amino acids. While body composition in cirrhosis may improve with diet and exercise prescription, suitably powered RCTs of combined interventions, targeting overweight/obese populations, and using guideline-recommended body composition measures are needed to clarify if sarcopenia/sarcopenic obesity is modifiable in patients with cirrhosis.

Recent Epidemiology and Risk Factors of Nonalcoholic Fatty Liver Disease

Because of the global obesity epidemic, the incidence and prevalence of nonalcoholic fatty liver disease (NAFLD) have increased worldwide, including among Koreans. Recently, the incidence rate of NAFLD in Korea was reported to be 45.1 per 1,000 person-years, and the prevalence as approximately 30% depending on the diagnostic methods used. The incidence of advanced fibrosis and hepatocellular carcinoma, as well as all-cause and liver-related mortality in NAFLD patients has increased substantially, imposing considerable public health costs in Korea. Genetic, demographic, environmental, and clinical factors are involved in the pathogenesis of NAFLD. Some genetic variants, such as patatin-like phospholipase domain-containing 3 (PNPLA-3) and sorting and assembly machinery component 50 (SAMM-50), play a major role in the occurrence of NAFLD. The risk of NAFLD and fibrosis increases with advancing age and in men. Nutritional factors, inadequate exercise, and sleep duration are also associated with increased risk of NAFLD. Obesity is a major risk factor for NAFLD; however, NAFLD in lean individuals has been noted in recent studies. Insulin resistance, type 2 diabetes, and metabolic syndrome and its components are closely associated with NAFLD development and liver fibrosis with various underlying mechanisms. Sarcopenia likely shares a common pathophysiology with NAFLD. The rapidly increasing incidence and prevalence of NAFLD and its complications, as well as the associated healthcare burden, warrant early assessment of NAFLD and its risk factors to prevent NAFLD-related complications in high risk groups.

Impact of Sarcopenia on the Severity of the Liver Damage in Patients With Non-alcoholic Fatty Liver Disease

An extensive body of the literature shows a strong interrelationship between the pathogenic pathways of non-alcoholic fatty liver disease (NAFLD) and sarcopenia through the muscle-liver-adipose tissue axis. NAFLD is one of the leading causes of chronic liver diseases (CLD) affecting more than one-quarter of the general population worldwide. The disease severity spectrum ranges from simple steatosis to non-alcoholic steatohepatitis (NASH), cirrhosis, and its complications: end-stage chronic liver disease and hepatocellular carcinoma. Sarcopenia, defined as a progressive loss of the skeletal muscle mass, reduces physical performances, is associated with metabolic dysfunction and, possibly, has a causative role in NAFLD pathogenesis. Muscle mass is a key determinant of the whole-body insulin-mediated glucose metabolism and impacts fatty liver oxidation and energy homeostasis. These mechanisms drive the accumulation of ectopic fat both in the liver (steatosis, fatty liver) and in the muscle (myosteatosis). Myosteatosis rather than the muscle mass per se, seems to be closely associated with the severity of the liver injury. Sarcopenic obesity is a recently described entity which associates both sarcopenia and obesity and may trigger worse clinical outcomes including hepatic fibrosis progression and musculoskeletal disabilities. Furthermore, the muscle-liver-adipose tissue axis has a pivotal role in changes of the body composition, resulting in a distinct clinical phenotype that enables the identification of the "sarcopenic NAFLD phenotype." This review aims to bring some light into the complex relationship between sarcopenia and NAFLD and critically discuss the key mechanisms linking NAFLD to sarcopenia, as well as some of the clinical consequences associated with the coexistence of these two entities: the impact of body composition phenotypes on muscle morphology, the concept of sarcopenic obesity, the relationship between sarcopenia and the severity of the liver damage and finally, the future directions and the existing gaps in the knowledge.

Skeletal muscle loss is associated with diabetes in middle-aged and older Chinese men without non-alcoholic fatty liver disease

BACKGROUND

Skeletal muscle, a key insulin target organ, has been reported to be associated with diabetes mellitus (DM). Compared to non-diabetic patients, diabetic patients have decreased muscle mass and a higher prevalence of sarcopenia, and patients with sarcopenia may be at increased risk of developing diabetes. In individuals with nonalcoholic fatty liver disease (NAFLD), sarcopenia is associated with the severity of fibrosis and steatosis. Previous studies have demonstrated that NAFLD is strongly associated with DM and sarcopenia.

AIM

To determine the relationship between skeletal muscle mass and DM in Chinese middle-aged and elderly men, and whether the association is affected by NAFLD.

METHODS

Skeletal muscle mass was calculated as appendicular skeletal muscle mass (ASM) in kg/body weight × 100%. Liver fat content (LFC) was measured using a quantitative ultrasound method.

RESULTS

As the ASM decreased, fasting blood glucose (FBG), 2-h postprandial blood glucose (2hBG), and LFC increased in both genders, as did the prevalence of DM and NAFLD. Spearman analysis showed that the ASM was negatively correlated with the FBG, 2hBG, and LFC. Stepwise logistic regression analysis showed that after adjustments, the ASM quartile was negatively associated with the presence of DM in males, but not in females. Subgroup analysis showed that the ASM quartiles remained negatively correlated with the presence of DM in the non-NAFLD population (including males and females), but no correlation was found between ASM quartiles and the presence of DM in the NAFLD population. When stratified by LFC quartiles, ASM was negatively correlated with the presence of DM in the first and second LFC quartiles in males.

CONCLUSION

Skeletal muscle mass loss was shown to be associated with the presence of DM in males, but not in females; NAFLD weakens this association. The results suggested that the stratified management of diabetes mellitus should be considered according to skeletal muscle mass and NAFLD.

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.

Binge-eating disorder is associated with an unfavorable body mass composition in patients with non-alcoholic fatty liver disease

The interaction between eating disorders and non-alcoholic fatty liver disease (NAFLD) remains unexplored, especially with regards to binge-eating disorder (BED). Our team conducted a service evaluation project in order to assess risk factors for the presence of BED among patients with NAFLD and the impact of BED on body mass composition. The overall prevalence of patients screening positive to BED Screener-7 (BEDS-7) was 28.4%, while a previous diagnosis of depression and marital status (as single or separated) were independently associated with positive BED. Furthermore, patients with positive BEDS-7 had higher BMI, with greater visceral component and overall lower muscle mass. There was no difference in terms of liver disease severity as assessed by noninvasive markers of fibrosis. However, as body mass composition and sarcopenia have been shown to be associated to disease progression in patients with NAFLD, further studies are required to ascertain the long-term impact of BED in these patients. Moreover, further work is warranted to identify to implement multidisciplinary approach within clinical psychology for the management of patients with BED, who may be particularly challenging in terms of achieving lifestyle modifications. As a hepatology community, we should address NAFLD with a more holistic approach.

Serum testosterone levels and testosterone supplementation in cirrhosis: A systematic review

BACKGROUND & AIMS

Cirrhosis disrupts the hypothalamic-pituitary-gonadal axis causing low testosterone. Testosterone deficiency is associated with sarcopenia and osteopenia, leading to a state of frailty and worse clinical outcomes, morbidity and mortality. We aimed to conduct a systematic review on the relationship between serum testosterone and laboratory, anthropometric and clinical outcomes in observational and interventional studies in cirrhosis.

METHODS

PubMed and EMBASE were searched from inception through 27 August 2020 and reviewed independently by two investigators; a third reviewer solved disagreement. A qualitative summary of relevant findings was done. Methodological quality was assessed using the Newcastle Ottawa Scale for non-interventional studies and the Cochrane Risk of Bias for interventional studies.

RESULTS

Out of 3569 articles, 15 met inclusion criteria with six observational studies of 1267 patients and nine interventional studies of 580 patients. In observational studies, low serum testosterone level was associated with sarcopenia, shorter median time to hepatic decompensation, transplant requirement, higher model for end-stage liver disease (MELD) scores, and death in cirrhotic patients. Nine interventional studies (361 treated with testosterone vs 219 placebo, 1-36 months) showed that testosterone supplementation improved serum testosterone, appendicular mass and bone mineral density. However, no trial reported improvement in liver-related scores, complications, readmission rates or death.

CONCLUSIONS

Low serum testosterone is associated with increased morbidity and mortality in cirrhosis patients. Testosterone supplementation improved intermediate endpoints, but there was no conclusive data on clinical outcomes. Testosterone supplementation may be a promising strategy to improve frailty and decrease significant clinical complications in cirrhosis.

Sarcopenia in nonalcoholic fatty liver disease and all-cause and cause-specific mortality in the United States

BACKGROUND & AIMS

Nonalcoholic fatty liver disease (NAFLD) has been associated with sarcopenia. However, mortality in the setting of NAFLD-related sarcopenia remains undefined. We aim to determine the all-cause and cause-specific mortality from sarcopenia among adults with NAFLD in the USA.

METHODS

11 065 individuals in the Third National Health and Nutrition Examination Survey were studied and linked mortality through 2015 was analysed. NAFLD was diagnosed based on presence of ultrasonographic hepatic steatosis without other known liver diseases. Sarcopenia was defined as skeletal muscle index determined by bioelectrical impedance analysis. The Cox proportional hazard model was used to assess all-cause mortality and cause-specific mortality, and hazard ratio (HR) adjusted for known risk factors.

RESULTS

During a median follow-up of 23 years or more, sarcopenia was associated with increased all-cause mortality (HR 1.27, 95% confidence interval [CI] 1.11-1.44). Only in individuals with NAFLD, sarcopenia was associated with a higher risk for all-cause mortality, while this association was absent in those without NAFLD. Individuals with both sarcopenia and NAFLD had a higher risk for all-cause mortality (HR 1.28 95% CI 1.06-1.55) compared with those without sarcopenia and NAFLD. Furthermore, sarcopenia was associated with a higher risk for cancer- and diabetes-related mortality among those with NAFLD. This association was not noted in those without NAFLD.

CONCLUSION

In this nationally representative sample of US adults, sarcopenia was associated with a higher risk for all-cause, cancer- and diabetes-related mortality in individuals with NAFLD.

Physiologic Reserve Assessment and Application in Clinical and Research Settings in Liver Transplantation

Physiologic reserve is an important prognostic indicator. Because of its complexity, no single test can measure an individual's physiologic reserve. Frailty is the phenotypic expression of decreased reserve and portends poor prognosis. Both subjective and objective tools have been used to measure one or more components of physiologic reserve. Most of these tools appear to predict pretransplant mortality, but only some predict posttransplant survival. Incorporation of these measures of physiologic reserve in the clinical and research settings including prediction models are reviewed, and the applicability to patient-related outcomes are discussed. Commonly used tools, in patients with cirrhosis, that have been associated with clinical outcomes were reviewed. The strength of subjective tools lies in low-cost, wide availability, and quick assessments at the bedside. A disadvantage of these tools is the manipulative capacity, restricting their value in allocation processes. The strength of objective tests lies in objective measurements and the ability to measure change. The disadvantages include complexity, increased cost, and limited accessibility. Heterogeneity in the definitions and tools used has prevented further advancement or a clear role in transplant assessment. Consistent use of objective tools, including the 6-minute walk test, gait speed, Liver Frailty Index, or Short Physical Performance Battery, are recommended in clinical and research settings.

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.

Frailty and Sarcopenia in Patients Pre- and Post-Liver Transplant

Greater than half of patients with decompensated liver disease suffer from frailty and/or sarcopenia, which can lead to increased pre- and post-liver transplant morbidity and mortality. Although frailty and sarcopenia can impact patients with end-stage liver disease in similar ways, they are unique clinical entities with differing underlying etiologies. Early assessment and identification of frailty and sarcopenia in patients is critical to guide clinical decision-making regarding transplantation and to implement nutritional and exercise-based treatment regiments. Nonetheless, accurate diagnosis and, in particular, predicting patients that will develop frailty and/or sarcopenia remains challenging, and the success of clinical interventions is limited.

Sarcopenia is associated with the presence of nonalcoholic fatty liver disease in Zhejiang Province, China: a cross-sectional observational study

Background

Currently, both non-alcoholic fatty liver disease (NAFLD) and sarcopenia have attracted extensive attention in public health. However, the relationship between NAFLD and sarcopenia remains unclear. This study aimed to clarify the sex-specific association between sarcopenia and NAFLD according to the Asian Working Group for Sarcopenia (AWGS).

Methods

Dual-energy X-ray absorptiometry (DXA) and hepatic ultrasonography were measured in 578 participants (92 men and 486 women) during their annual health examinations. Multivariate logistic regression models were used to explore the association between NAFLD and sarcopenia with its two components.

Results

A total of 154 participants (30 men and 124 women) had NAFLD. The prevalence of sarcopenia was higher among the participants with NAFLD than among those without NAFLD (men: 20.0% vs. 9.7%, P = 0.295, women: 15.3% vs. 8.0%, P = 0.019). Low muscle mass (LMM) was independently associated with NAFLD in both men and women (men: odds ratio [OR], 2.88; 95% confidence interval [CI] 1.52–5.46; women: OR, 2.08; 95% CI 1.63–2.67). However, low muscle strength (LMS) was independently associated with NAFLD only in male participants, with an OR of 1.15 (95% CI 1.02–1.28).

Conclusion

The occurrence of sarcopenia was associated with a higher risk of NAFLD, especially in men, as demonstrated by lower muscle mass and lower muscle strength.

Endpoints and design of clinical trials in patients with decompensated cirrhosis: Position paper of the LiverHope Consortium

Management of decompensated cirrhosis is currently geared towards the treatment of complications once they occur. To date there is no established disease-modifying therapy aimed at halting progression of the disease and preventing the development of complications in patients with decompensated cirrhosis. The design of clinical trials to investigate new therapies for patients with decompensated cirrhosis is complex. The population of patients with decompensated cirrhosis is heterogeneous (i.e., different etiologies, comorbidities and disease severity), leading to the inclusion of diverse populations in clinical trials. In addition, primary endpoints selected for trials that include patients with decompensated cirrhosis are not homogeneous and at times may not be appropriate. This leads to difficulties in comparing results obtained from different trials. Against this background, the LiverHope Consortium organized a meeting of experts, the goal of which was to develop recommendations for the design of clinical trials and to define appropriate endpoints, both for trials aimed at modifying the natural history and preventing progression of decompensated cirrhosis, as well as for trials aimed at managing the individual complications of cirrhosis.

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.

Adverse muscle composition is linked to poor functional performance and metabolic comorbidities in NAFLD

Background & Aims

Sarcopenia and frailty are recognised as important factors in later stages of liver disease. However, their role in non-alcoholic fatty liver disease (NAFLD) is not yet fully understood. In this study we investigate the associations of MRI-measured adverse muscle composition (AMC: low muscle volume and high muscle fat) with poor function, sarcopenia, and metabolic comorbidity within NAFLD in the large UK Biobank imaging study.

Methods

A total of 9,545 participants were included. Liver fat, fat-tissue free muscle volume, and muscle fat infiltration were quantified using a rapid MRI protocol and automated image analysis (AMRA® Researcher). For each participant, a personalised muscle volume z-score (sex- and body size-specific) was calculated and combined with muscle fat infiltration for AMC detection. The following outcomes were investigated: functional performance (hand grip strength, walking pace, stair climbing, falls) and metabolic comorbidities (coronary heart disease, type 2 diabetes). Sarcopenia was detected by combining MRI thresholds for low muscle quantity and low hand grip strength according to the European working group definition.

Results

The prevalence of sarcopenia in NAFLD (1.6%) was significantly lower (p <0.05) compared with controls without fatty liver (3.4%), whereas the prevalence of poor function and metabolic comorbidity was similar or higher. Of the 1,204 participants with NAFLD, 169 (14%) had AMC and showed 1.7–2.4× higher prevalence of poor function (all p <0.05) as well as 2.1× and 3.3× higher prevalence of type 2 diabetes and coronary heart disease (p <0.001), respectively, compared with those without AMC.

Conclusions

AMC is a prevalent and highly vulnerable NAFLD phenotype displaying poor function and high prevalence of metabolic comorbidity. Sarcopenia guidelines can be strengthened by including cut-offs for muscle fat, enabling AMC detection.

Lay summary

Today, it is hard to predict whether a patient with fatty liver disease will progress to more severe liver disease. This study shows that measuring muscle health (the patient's muscle volume and how much fat they have in their muscles) could help identify the more vulnerable patients and enable early prevention of severe liver disease.

•

The role of sarcopenia and frailty in NAFLD is not yet fully understood.

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Magnetic resonance imaging enables quantification of muscle composition.

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Myosteatosis in combination with low muscle volume characterises an adverse muscle composition.

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Adverse muscle composition is a novel NAFLD phenotype associated with poor function and metabolic comorbidity.

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Sarcopenia guidelines can be strengthened by including cut-offs for muscle fat.

Physical Function Measured Prior to Lung Transplantation Is Associated With Posttransplant Patient Outcomes

INTRODUCTION

The primary objective of this study was to determine whether pretransplant physical function is correlated with posttransplantation outcomes.

METHODS

We performed a retrospective study of patients that participated in pretransplantation screening and subsequently underwent lung transplantation. Pretransplant variables of interest included demographics, muscle mass, body composition, physical function, and physical frailty. Correlation tests were performed to assess relationships with significance set at 0.05.

RESULTS

Twenty-five patients with a mean age of 57 ± 13 years (68% male) with pretransplant lung allocation score of 45 ± 14 were included. This cohort had a 3-year mortality rate of 32% (n = 8). Pretransplant 4-m gait speed was significantly related to performance on the Short Physical Performance Battery (r = 0.74, P = .02) and distance ambulated on the 6-minute walk test (r = 0.62, P = .07) at hospital discharge. Older age was associated with slower gait speed and worse performance on sit-to-stand testing at hospital discharge (r = -0.76, P = .01 and r = -0.75, P = .01, respectively). Statistically, only diagnosis of cystic fibrosis was associated with 3-year mortality.

DISCUSSION

Our study demonstrates that demographic, clinical, and physical function assessed prior to lung transplantation may be indicators of functional recovery.

Optimizing patients with non-alcoholic fatty liver disease pre-transplant

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in Western countries. Non-alcoholic steatohepatitis (NASH), which is the progressive counterpart of the disease, is becoming the leading indication for liver transplantation in North America. Owing to the lack of symptoms, NASH is often an incidental diagnosis, resulting in a significant proportion of patients being diagnosed when advanced liver disease has already developed. NAFLD has recently been characterized as the hepatic manifestation of metabolic syndrome. Consequently, it is a multisystem disease that often co-exists with several other conditions, such as obesity, diabetes, cardiovascular diseases, and extra-hepatic malignancy, which have an impact on selection of transplant recipients. The complexity of diagnostic approach, need for multidisciplinary clinical management, and lack of a specific treatment further complicate the picture of this extremely prevalent liver condition. NAFLD patients with advanced liver disease should be considered for early referral to liver transplant clinics for careful metabolic and cardiovascular risk stratification because they have worse survival rates after liver transplantation than other patients with chronic liver disease. Early referral will also facilitate optimization of metabolic comorbidities before proceeding with transplantation. This review provides an overview of strategies to identify patients with advanced NAFLD, with an emphasis on the management of associated comorbidities and optimal timing of pre-transplant evaluation. Other topics that have been shown to affect recipient optimization, such as the role of lifestyle changes and bariatric surgery in the management of obesity, as well as sarcopenia in decompensated NASH-related cirrhosis, are addressed.

Intra-Aortic Balloon Pump Bridging to Heart Transplantation: Impact of the 2018 Allocation Change

BACKGROUND

This study evaluates the impact of the 2018 allocation policy change on outcomes of orthotopic heart transplantation (OHT) in patients bridged with intra-aortic balloon pumps (IABPs).

METHODS

Adult (≥18 years) patients undergoing OHT between 2013 and 2019 who were bridged with an IABP were stratified based on temporal relation to the policy change. Univariate analysis was used to compare baseline characteristics and postoperative outcomes. Multivariate Cox regression analysis was used to estimate risk-adjusted predictors of post-transplant mortality.

RESULTS

A total of 1342 (8.6%) OHT patients were bridged with an IABP during the study period. Rates of bridging with IABP to OHT increased significantly after the policy change (7.0% versus 24.9%, P<0.001). The mean recipient age was 54.1±12.1 years with 981 (73.1%) patients being male. Baseline characteristics were similar between the 2 groups whereas post-policy change patients spent fewer days on the waitlist (15 versus 35 days, P<0.001), had longer ischemic times (3.5 versus 3.0 hours, P<0.001), and received organs from a greater distance (301 versus 105 miles, P<0.001). By multivariable analysis, days on the waitlist (for every 30 days; odds ratio, 1.01 [95% CI, 1.00-1.02], P=0.031) and diabetes mellitus (odds ratio, 1.87 [95% CI, 1.16-3.02], P=0.011) emerged as significant predictors of post-transplant mortality. After the policy change, waitlisted patients requiring IABP support were more likely to survive to transplant (76.4 versus 89.8%, P<0.001).

CONCLUSIONS

IABP utilization has increased over 3-fold since the 2018 policy change with improved waitlist outcomes and comparable post-OHT survival. Thus, bridging patients to OHT with IABPs appears to be an effective strategy in the current era.

Nonalcoholic Fatty Liver Disease Is Associated With Low Skeletal Muscle Mass in Overweight/Obese Youths

Background: Recent studies in adult non-elderly and elderly individuals have reported a link between nonalcoholic fatty liver disease (NAFLD) and sarcopenia. Nonetheless, whether this relationship would be found outside these populations it is still unknown. Hence, we evaluated the relationship between NAFLD and skeletal muscle mass in children and adolescents with overweight/obesity. Methods: Two-hundred and thirty-four overweight/obese youths were enrolled. NAFLD was diagnosed by ultrasononography, after exclusion of infectious and metabolic disorders. Forty of the patients with NAFLD had also liver biopsy. Total and regional lean body mass and total fat mass measurements were obtained by dual-energy X-ray absorptiometry. The relative muscle mass (RMM) was defined as the percent of muscle mass (kg) relative to the sum of muscle and fat (kg) mass. Appendicular skeletal muscle mass (ASM) was calculated by the sum of muscle masses of the four limbs (kg), and expressed as percent of body weight. Results: Subjects were stratified according to tertiles of RMM. The prevalence of abdominal obesity, dyslipidemia, insulin resistance, metabolic syndrome, NAFLD as well as biopsy-proven nonalcoholic steatohepatitis (NASH) was significantly increased in the lowest tertile of RMM. After controlling for age, sex and Tanner stage, children in the lowest tertile of RMM had an increased risk for NAFLD (OR= 2.80, 95% CI=1.57-5.02) compared to those in the other two tertiles. This association persisted after additional adjustments for clinical and metabolic variables. Similarly, the risk of NAFLD in the lowest tertile of ASM/weight index was significantly higher compared to those in the other two tertiles after adjustment for the above confounders. Conclusions: This is the first study to establish an independent association between low muscle mass and NAFLD/NASH in overweight/obese youths. Considering the worldwide increase of pediatric obesity, measurements of muscle mass may serve as useful method of identifying among obese children those at high metabolic risk who may need intensive lifestyle interventions to prevent NAFLD and its progression.

Sarcopenia in nonalcoholic fatty liver disease: new challenges for clinical practice

Introduction: Sarcopenia is increasingly recognized in patients with nonalcoholic liver disease (NAFLD). Initially recognized as a consequence of advanced liver disease, there is now emerging evidence that sarcopenia may be a novel risk factor for the development of NAFLD, with a role in fibrosis and disease progression.Areas covered: This review examines the epidemiology, pathogenesis, and complex interplay between NAFLD and sarcopenia. Furthermore, the authors discuss the challenges with diagnosis of sarcopenia in the clinic and the evidence-based management of sarcopenia in patients with NAFLD. A MEDLINE and PubMed search was undertaken using the terms; 'sarcopenia,' 'frailty,' 'muscle,' 'obesity,' 'non-alcoholic fatty liver disease,' 'non-alcoholic steatohepatitis', and 'cirrhosis' up to 31 September 2019.Expert opinion: Sarcopenia may be masked by the co-existence of morbid obesity, which is most notable in patients with NAFLD. Sarcopenia is a key indicator of adverse outcomes in patients with cirrhosis, such as hepatic decompensation, poor quality of life and premature mortality. Patients with NAFLD and advanced fibrosis/cirrhosis should undergo anthropometric measures (handgrip strength), dry body mass index, and measures of physical frailty (including muscle function, not just mass) to enable targeted early interventions of nutrition (low fat, 1.5 g/kg/day protein intake, 2-3 hourly food intake) and exercise (combined resistance and aerobic).

Cirrhosis and frailty assessment in elderly patients: A paradoxical result

The frailty represents a key determinant of elderly clinical assessment, especially because it allows the identification of risk factors potentially modifiable by clinical and therapeutic interventions. The frailty assessment in elderly patients usually is made by using of Fried criteria. However, to assess the frailty in cirrhotic patients, multiple but different tools are used by researchers. Thus, we aimed to compare frailty prevalence in elderly patients with well-compensated liver cirrhosis and without cirrhosis, according to Fried criteria.Among 205 elderly patients screened, a total of 148 patients were enrolled. The patients were divided into 2 groups according to the presence/absence of well-compensated liver cirrhosis.After clinical examination with conventional scores of cirrhosis, all patients underwent anthropometric measurements, nutritional, biochemical, comorbidity, and cognitive performances. Frailty assessment was evaluated according to Fried frailty criteria.Unexpectedly, according to the Fried criteria, non-cirrhotic patients were frailer (14.2%) than well-compensated liver cirrhotic patients (7.5%). The most represented Fried criterion was the unintentional weight loss in non-cirrhotic patients (10.1%) compared to well-compensated liver cirrhotic patients (1.4%). Moreover, cumulative illness rating scale -G severity score was significantly and positively associated with frailty status (r = 0.234, P < .004). In a multivariate linear regression model, only female gender, body mass index and mini nutritional assessment resulted associated with frailty status, independently of other confounding variables.Despite the fact that elderly cirrhotic patients are considered to be frailer than the non-cirrhotic elderly patient, relying solely on "mere visual appearance," our data show that paradoxically non-cirrhotic elderly patients are frailer than elderly well-compensated liver cirrhotic patients. Thus, clinical implication of this finding is that frailty assessment performed in the well-compensated liver cirrhotic patient can identify those cirrhotic patients who may benefit from tailored interventions similarly to non-cirrhotic elderly patients.

Sarcopenia in Cirrhosis: Looking Beyond the Skeletal Muscle Loss to See the Systemic Disease

Sarcopenia is a common complication of cirrhosis and is defined as a progressive and generalized loss of skeletal muscle mass, strength, and function. Sarcopenia is associated with poor prognosis and increased mortality. How sarcopenia and muscle wasting relate to such poor outcomes requires looking beyond the overt muscle loss and at this entity as a systemic disease that affects muscles of vital organs including cardiac and respiratory muscles. This review explores the pathophysiological pathways and mechanisms that culminate in poor outcomes associated with sarcopenia. This provides a launching pad to identify potential targets for therapeutic intervention and optimization to improve patient outcomes.

Frailty, Sarcopenia, and Malnutrition in Cirrhotic Patients

Sarcopenia, frailty, and malnutrition are prevalent complications in patients with end-stage liver disease (ESLD) and are associated with increased risk of morbidity and mortality. It is valuable to measure nutritional status, sarcopenia, and frailty over time in order to create interventions tailored to individuals with ESLD. Evaluating sarcopenia and frailty in patients with ESLD is challenging. Further work is needed to perfect these assessments so that clinicians can incorporate these assessments into their decision-making and management plans for cirrhotic patients.

Clinical and pathological features of sarcopenia-related indices in patients with non-alcoholic fatty liver disease

BACKGROUND

Sarcopenia is diagnosed with the skeletal muscle index (SMI) or the sarcopenia index (SI). We previously reported that the ratio of skeletal muscle mass to body fat mass (SF ratio) was a novel index of sarcopenia in patients with non-alcoholic fatty liver disease (NAFLD). The aim of this retrospective study was to evaluate sarcopenia with these indices in patients with NAFLD.

METHODS

One hundred and fifty-six consecutive patients with biopsy-proven NAFLD and alanine aminotransferase (ALT) >40 IU/L were enrolled. Liver function and body composition were evaluated in 121 patients after 12 months. We evaluated the relationship between histological findings, changes in liver function, and the SMI, SI, and SF ratio.

RESULTS

Of the 156 patients enrolled, 13.5% and 26.3% were diagnosed with sarcopenia with the SMI and SI. In patients with hepatic fibrosis stage <2, the SI and the SF ratio were significantly greater than in patients with fibrosis stage ≥2. There was no difference in SMI between groups. In the cohort assessed at baseline and 12 months later, transaminase activity and SMI decreased significantly, and the SF ratio increased over time. A multivariate analysis revealed the presence of the PNPLA3 G allele and an increase in SF ratio (odds ratio, 7.406) as predictive factors of ALT reduction >30% from baseline.

CONCLUSIONS

Due to the high prevalence of obesity, we should consider both skeletal muscle mass and body fat mass in the diagnosis and treatment of NAFLD. The SF ratio could be a useful index in sarcopenic NAFLD.

Hyperammonemia and proteostasis in cirrhosis

PURPOSE OF REVIEW

Skeletal muscle loss or sarcopenia is a frequent complication of cirrhosis that adversely affects clinical outcomes. As skeletal muscle is the largest store of proteins in the body, proteostasis or protein homeostasis is required for maintenance of muscle mass. This review will focus on disordered skeletal muscle proteostasis in liver disease.

RECENT FINDINGS

Increased skeletal muscle uptake of ammonia initiates responses that result in disordered proteostasis including impaired protein synthesis and increased autophagy. The cellular response to the stress of hyperammonemia (hyperammonemic stress response, HASR) involves the coordinated action of diverse signaling pathways targeting the molecular mechanisms of regulation of protein synthesis. Transcriptional upregulation of myostatin, a TGFβ superfamily member, results in impaired mTORC1 signaling. Phosphorylation of the eukaryotic translation initiation factor 2α (eIF2α) also relates to decreased global protein synthesis rates and mTORC1 signaling. Ammonia also causes mitochondrial and bioenergetic dysfunction because of cataplerosis of α-ketoglutarate. Lowering ammonia, targeting components of HASR and regulating cellular amino acid levels can potentially restore proteostasis.

SUMMARY

Signaling via myostatin and eIF2α phosphorylation causes decreases in protein synthesis and mTORC1 activity with a parallel mitochondrial dysfunction and increased autophagy contributing to proteostasis perturbations during skeletal muscle hyperammonemia of liver disease.

Sarcopenia in hiding: The risk and consequence of underestimating muscle dysfunction in nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide. Up to one third of individuals with NAFLD will develop nonalcoholic steatohepatitis (NASH), which is associated with progression to cirrhosis and is rapidly becoming the leading indication for liver transplantation. Sarcopenia is defined as a progressive and generalized loss of skeletal muscle mass, strength, and function. It is observed in up to 60% of patients with end-stage liver disease and portends a poor prognosis. Recent studies have shown that sarcopenia is a novel risk factor for developing NAFLD. Pathophysiological mechanisms relating sarcopenia and NASH may include insulin resistance (IR) and increased inflammation. IR leads to accumulation of triglycerides in both muscle tissue and the liver. It also exacerbates proteolysis and leads to muscle depletion. Chronic inflammation leads to liver injury and progression of fibrosis. The inflammatory milieu also stimulates protein catabolism. Viewing skeletal muscle as an endocrine organ that secretes various salutary myokines may help us understand its role in the development of steatosis. A better understanding of the pathophysiology will aid in developing physical and pharmacological therapeutic interventions. In this review, we will explore the complex inter-relationships between sarcopenia and NASH. We will discuss the impact of sarcopenia in patients with NASH and therapeutic options for the management of sarcopenia. (Hepatology 2017;66:2055-2065).