Assessment and significance of sarcopenia in liver transplantation

Sarcopenic obesity is significantly associated with poorer overall survival after liver transplantation: a systematic review and meta-analysis

Background

Sarcopenia has been shown to worsen survival after liver transplantation. However, it remains unclear whether coexisting sarcopenia and obesity, so-called sarcopenic obesity (SO), may also synergistically increase their adverse effects. This meta-analysis aimed to evaluate whether pre-transplant SO independently predicts survival in this population.

Methods

We conducted this study according to the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. The PubMed, Embase, Web of Science, Wanfang, CNKI, and Cochrane databases were searched up to 15 October 2023, for studies with any study design evaluating the relationship between SO and post-transplant survival in patients undergoing liver transplantation. We used ROBINS-E to assess the study quality. The primary outcome was all-cause mortality at any length of follow-up. We calculated pooled odds risks (ORs) or hazard risks (HRs) with 95% confidence intervals (CIs). Heterogeneity was quantified with I 2 statistics. Subgroup analyses and publication bias evaluations were also conducted.

Results

We included nine cohort studies with 2,416 patients. These studies were moderate to high quality. Pre-liver transplant patients commonly experience SO, with a mean prevalence as high as 34%. Overall, patients with SO exhibited a significantly higher overall mortality than patients without SO, as demonstrated by pooled studies using both univariate analysis [HR = 1.76, 95%C 1.33-2.33, p < 0.0001] and multivariate analysis (HR = 2.33, 95%CI 1.34-4.04, p = 0.003). Similar results were also found when comparing patients with or without SO at 1, 3, and 5 years of follow-up (OR = 1.86, 95%CI 1.22-2.83; OR = 1.83, 95%CI: 1.27-2.64; and OR = 1.54, 95% CI 1.02-2.34, respectively). In addition, subgroup analysis based on studies that reported HRs of both sarcopenia and SO indicated both had independent negative effects on post-transplant survival.

Conclusion

Our meta-analysis showed that SO occurs frequently in liver transplant patients. SO is associated with an increased risk of mortality in such patient populations.

Systematic review registration

https://doi.org/10.37766/inplasy2024.2.0069 [inplasy2024.2.0069].

Frailty after Liver Transplantation: A Complex Unexplored Issue

Frailty is a multidimensional syndrome predominantly studied in the elderly, characterized by reduced resistance to stressors due to diminished physiological reserve and resilience. Advances in surgical techniques and immunosuppressive drugs have improved long-term survival rates in solid organ transplant recipients, yet the 10-year survival is satisfying. However, liver transplant recipients have a noteworthy risk of developing frailty status. After liver transplant, frailty can be favored by socioeconomic, cultural, and health-related factors, leading to increased risks of hospitalization, morbidity, and mortality. Various tools for frailty assessment exist, but none are universally validated for post-transplant patients. The integration of socioeconomic and psychological factors into frailty evaluation could improve quality of life and long-term outcomes for transplant recipients. Multidisciplinary approaches, including psychosocial support, are essential for managing frailty and enhancing the overall care of transplanted patients. This narrative review aims to comprehensively address the principal frailty risk factors associated with liver transplantation.

Effect of pretransplant sarcopenia on patient and graft outcomes in solid organ transplant recipients: A systematic review and meta-analysis

The relationship between sarcopenia and prognosis in solid organ transplantation recipients (SOTr) remains unverified. We aimed to quantify the prevalence of pretransplant sarcopenia and its effect on patient and graft survival in SOTr. We used PubMed, EMBASE, Cochrane Library and Web of Science to search relevant studies published in English (from inception to December 31, 2021). Prospective and retrospective cohort studies that reported the prevalence of sarcopenia before transplant or the association between sarcopenia and clinical outcomes in SOTr were included. Primary outcomes were the prevalence of sarcopenia and its impact on patient and graft survival. Secondary outcomes included perioperative complications, acute rejection, length of hospital stay, length of intensive care unit stay (ICU LOS) and early readmission. Thirty-nine studies involving 5792 patients were included. Pooled prevalence of sarcopenia amongst SOTr candidates was 40 % (95 % confidence interval [CI]: 34%-47 % and I2 = 97 %). Sarcopenia was associated with increased risk of death (hazard ratio [HR] = 1.87, 95 % CI: 1.46-2.41 and I2 = 60 %), poor graft survival (HR = 1.71, 95 % CI: 1.16-2.54 and I2 = 57 %) and increased liver graft loss (HR = 1.43, 95 % CI: 1.03-1.99 and I2 = 38 %). Patients with sarcopenia demonstrated increased incidence of perioperative complications (risk ratio [RR] = 1.34, 95 % CI: 1.17-1.53 and I2 = 40 %), long ICU LOS (mean difference = 2.31 days, 95 % CI: 0.58-4.04 and I2 = 97 %) and decreased risk of acute rejection (RR = 0.61, 95 % CI: 0.42-0.89 and I2 = 0 %). In Conclusion, sarcopenia is prevalent in SOTr candidates and associated with death and graft loss. Identifying sarcopenia before transplantation and intervening may improve long-term outcomes.

Post Living Donor Liver Transplantation Small-for-size Syndrome: Definitions, Timelines, Biochemical, and Clinical Factors for Diagnosis: Guidelines From the ILTS-iLDLT-LTSI Consensus Conference

BACKGROUND

When a partial liver graft is unable to meet the demands of the recipient, a clinical phenomenon, small-for-size syndrome (SFSS), may ensue. Clear definition, diagnosis, and management are needed to optimize transplant outcomes.

METHODS

A Consensus Scientific committee (106 members from 21 countries) performed an extensive literature review on specific aspects of SFSS, recommendations underwent blinded review by an independent panel, and discussion/voting on the recommendations occurred at the Consensus Conference.

RESULTS

The ideal graft-to-recipient weight ratio of ≥0.8% (or graft volume standard liver volume ratio of ≥40%) is recommended. It is also recommended to measure portal pressure or portal blood flow during living donor liver transplantation and maintain a postreperfusion portal pressure of <15 mm Hg and/or portal blood flow of <250 mL/min/100 g graft weight to optimize outcomes. The typical time point to diagnose SFSS is the postoperative day 7 to facilitate treatment and intervention. An objective 3-grade stratification of severity for protocolized management of SFSS is proposed.

CONCLUSIONS

The proposed grading system based on clinical and biochemical factors will help clinicians in the early identification of patients at risk of developing SFSS and institute timely therapeutic measures. The validity of this newly created grading system should be evaluated in future prospective studies.

CT-derived psoas muscle area and density are associated with length of stay and discharge disposition after liver transplantation

BACKGROUND & AIMS

Prolonged length of stay (LOS) and discharge disposition following liver transplantation are associated with postoperative complications and increased healthcare utilization. This study evaluated the relationship between CT-derived psoas muscle measurements and hospital LOS, intensive care unit (ICU) LOS, and discharge disposition after liver transplant. The psoas muscle was chosen given its ease of measurement with any radiological software. A secondary analysis assessed the relationship between the American Society for Parenteral and Enteral Nutrition and the Academy of Nutrition and Dietetics (ASPEN/AND) malnutrition diagnosis criteria and CT-derived psoas muscle measures.

METHODS

CT-derived measures of psoas muscle density (mHU) and cross-sectional area at the level of the third lumbar vertebrae were obtained from preoperative CT scans of liver transplant recipients. Cross-sectional area measures were corrected for body size to generate a psoas area index variable (cm²/m²; PAI).

RESULTS

Each 1-unit increase in PAI was associated with a reduced hospital LOS of 4 days (R² = 0.07). Each 5-unit increase in mean Hounsfield units (mHU) was associated with a reduced hospital and ICU LOS of 5 and 1.6 days, respectively (R² = 0.22 and 0.14, respectively). Mean PAI and mHU were higher in patients who discharged to home. PAI was reasonably identified through ASPEN/AND malnutrition criteria, but there was no difference in mHU between those with and without malnutrition.

CONCLUSION

Measures of psoas density were associated with both hospital and ICU LOS and discharge disposition. PAI was associated with hospital LOS and discharge disposition. CT-derived measures of psoas density may be a valuable complement to preoperative liver transplant nutrition assessment using traditional ASPEN/AND malnutrition criteria.

Effect of Preoperative Sarcopenia, Malnutrition and Functional status on Postoperative Morbidity Following Liver Transplantation

INTRODUCTION

The effect of sarcopenia, malnutrition, and functional status on immediate post liver transplantation outcome is not well established. Most studies on sarcopenia are related to 1 and 3-year mortality. Studies evaluating the effect of malnutrition are at least a decade old.

PROJECT AIMS

We evaluated the effect of preoperative sarcopenia, malnutrition, and functional status on postoperative length of hospital and ICU stay, incidence of complications, and mortality.

DESIGN

In this prospective study conducted on living donor liver transplant recipients, sarcopenia and malnutrition were identified using the psoas muscle thickness to height and the Royal Free Hospital- Nutritional Prioritizing Tool respectively. The Eastern Cooperative Oncology Group performance status score was noted. Postoperatively, length-of-hospital stay, ICU stay, duration of mechanical ventilation and incidence of postoperative complications were noted.

RESULTS

Hospital and ICU length of stay, and duration of mechanical ventilation were greater in sarcopenic versus non-sarcopenic patients (35.9 (14.6) versus 26.7 (10.7) days, P  =  0.02; 12.9 (4.8) versus 9.6 (3.8) days, P  =  0.02 and 8 [5,23] versus 5 [4,7] days, P  =  0.01 respectively). The incidence of acute kidney injury was higher in patients with sarcopenia (53.3% vs 19.4%, P  =  0.02). Patients with malnutrition and repeated hospitalizations had higher ICU stays but hospital length of stay duration of mechanical ventilation or the incidence of postoperative complications were not affected. The Eastern Cooperative Oncology Group score did not affect postoperative outcome.

CONCLUSION

In living donor liver transplant recipients, sarcopenia increased hospital and ICU stays, and duration of mechanical ventilation postoperatively. Malnutrition increased ICU stays.

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%.

Body composition and the skeletal muscle compartment in liver transplantation: Turning challenges into opportunities

Frailty, nutritional status, and body composition are increasingly under the spotlight of interest in various clinical scenarios including liver transplantation. To address the rapidly accumulating evidence in this field, recent European and North American practice guidelines have clearly underlined the clinical importance of nutritional status and body composition with adopting their assessment in patients with liver disease and in transplant candidates into their recommendations. While earlier reports, and therefore present guidelines, were focusing predominantly on quantitative alterations of the skeletal muscle mass (sarcopenia), recent studies have identified qualitative alterations such as intramuscular fat accumulation (myosteatosis) and sarcopenic obesity as emerging risk factors for poor clinical outcomes. In this review, the role of body composition in the context of liver transplantation will be discussed with a focus on the skeletal muscle compartment. A brief overview of current assessment modalities including their limitations, diagnostic challenges, prognostic significance, and pathophysiology are included. Possibilities to incorporate body composition parameters into clinical decision making are discussed. In addition, novel trends and remaining challenges in the therapeutic targeting of body composition and the skeletal muscle compartment are highlighted.

A Sarcopenia-Based Prediction Model for Postoperative Complications of ex vivo Liver Resection and Autotransplantation to Treat End-Stage Hepatic Alveolar Echinococcosis

Background

Sarcopenia and visceral adiposity have been shown to be associated with postoperative complications in numerous diseases. However, their effects on the postoperative complications of end-stage hepatic alveolar echinococcosis (HAE) patients undergoing ex vivo liver resection and autotransplantation (ELRA) remain unclear.

Methods

This retrospective study included 101 end-stage HAE patients who underwent ELRA from January 2014 to August 2020. We measured the skeletal muscle and adipose tissue of all patients at the level of the third lumbar vertebra on plain abdominal computed tomography (CT) images and subsequently derived an equation via least absolute shrinkage and selection operator (LASSO) regression analysis to calculate the sarcopenia score. Univariate and multivariate regression were performed to reveal the relationship between major postoperative complications and perioperative clinical data, and the obtained nomogram was validated with the bootstrapping method.

Results

The sarcopenia score was constructed as a personalized indicator to evaluate sarcopenia and visceral adiposity in each patient. Logistic regression analysis finally selected duration from primary diagnosis to obvious symptoms (OR=1.024, 95% CI, 1.007-1.042), surgical time (OR=1.003, 95% CI, 0.999-1.007) and sarcopenia score (OR=4.283, 95% CI, 1.739-10.551) as independent risk factors for predicting major postoperative complications following ELRA for end-stage HAE patients. The area under the receiver operating characteristic curve (AUROC) of 0.807 (95% CI, 0.720-0.895) and the calibration curve for this prediction model were satisfactory.

Conclusion

The sarcopenia score, which systematically evaluates the skeletal muscle and adipose tissue of end-stage HAE patients, was a significant predictive factor for major postoperative complications of ELRA. Relevant interventions should be conducted for those who have a high risk of postoperative complications according to the nomogram.

Pre-transplant Psoas Muscle Density as a Ready-to-Use and Low-cost Predictor of Patient Survival After Liver Transplant

Background: Sarcopenia, defined as low muscle mass with reduced function, is frequently encountered in cirrhotic patients and is a major predictor of adverse events, including post-liver transplant (LT) outcome. Objectives: This study assessed the impact of sarcopenia using computed tomography (CT)-based measurements on post-LT mortality and complications. Methods: From January 2008 to June 2016, 646 adult patients underwent 613 LTs at our institution. We analyzed the postoperative outcome of 287 patients who had pathologically proven cirrhosis on the explanted liver and who had performed a CT examination three months before LT. Psoas muscle density (PMD) was detected for every patient using standard instruments present in the radiological workstation and was related to postoperative survival rates and complications. Statistical analysis was carried out using the appropriate tests. Results: Postoperative mortality was 6.3%. At least one grade III-IV postoperative complication was experienced by 121 patients. Respiratory and infective complications occurred in 30 and 32 patients, respectively. Also, PMD was an independent predictor of postoperative mortality (P = 0.021), respiratory complications (P = 0.015), and infections (P = 0.010). The ROC analysis identified a PMD ≤ 43.72 HU as the best cutoff value for predicting 90-day mortality after LT. Conclusions: Psoas muscle density accurately predicted post-LT mortality and complications. Its ease and low-cost determination can allow widespread use of this parameter to improve clinical care and help with the decision to give these patients some priority on the transplant waiting list.

Association of Sarcopenia and Body Composition With Short-term Outcomes After Liver Resection for Malignant Tumors

IMPORTANCE

Previous retrospective studies have shown that sarcopenia substantially alters the postoperative and oncological outcomes after liver resection for malignant tumors. However, the evidence is limited to small retrospective studies with heterogeneous results and the lack of standardized measurements of sarcopenia.

OBJECTIVE

To investigate the role of sarcopenia as a risk factor associated with 90-day morbidity after liver resection for malignant tumors.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study included 234 consecutive patients undergoing liver resection for malignant tumors at San Camillo Forlanini Hospital, Rome, Italy, between June 1, 2018, and December 15, 2019. Muscle mass and strength were assessed using the skeletal muscle index (SMI) on preoperative computed tomographic scans and the handgrip strength test, respectively. Patients were then divided into the following 4 groups: group A (normal muscle mass and strength), group B (reduced muscle strength), group C (reduced muscle mass), and group D (reduced muscle mass and strength).

MAIN OUTCOMES AND MEASURES

The primary outcome of the study was 90-day morbidity. The following secondary outcomes were investigated: 90-day mortality, hospital stay, and readmission rate.

RESULTS

Sixty-four major and 170 minor hepatectomies were performed in 234 patients (median age, 66.50 [interquartile range, 58.00-74.25] years; 158 men [67.5%]). The median SMI of the entire population was 46.22 (interquartile range, 38.60-58.20) cm/m2. The median handgrip strength was 30.80 (interquartile range, 22.30-36.90) kg. Patients in group D had a statistically significantly higher rate of 90-day morbidity than patients in the other groups (51.5% [35 of 68] vs 38.7% [29 of 75] in group C, 23.1% [3 of 13] in group B, and 6.4% [5 of 78] in group A; P < .001). Compared with patients in the other groups, those in group D had a longer hospital stay (10 days vs 8 days in group C, 9 days in group B, and 6 days in group A; P < .001), and more patients in this group were readmitted to the hospital (8.8% [6 of 68] vs 5.3% [4 of 75] in group C, 7.7% [1 of 13] in group B, and 0% [0 of 78] in group A; P = .02). Sarcopenia, portal hypertension, liver cirrhosis, and biliary reconstruction were independent risk factors associated with 90-day morbidity.

CONCLUSIONS AND RELEVANCE

Sarcopenia appears to be associated with adverse outcomes after liver resection for malignant tumors. Both muscle mass measurements on computed tomographic scans and muscle strength assessments with the handgrip strength test should be performed at the first clinical encounter to better classify patients and to minimize the risk of morbidity.

Impact of Preoperative Low Prognostic Nutritional Index and High Intramuscular Adipose Tissue Content on Outcomes of Patients with Oral Squamous Cell Carcinoma

The impact of preoperative malnutrition and sarcopenia on survival in oral squamous cell carcinoma (OSCC) patients remains controversial. We investigated the effects of the preoperative nutritional status and abnormalities in body composition on the mortality of OSCC patients. A retrospective study involving 103 patients with OSCC was conducted. Disease-specific survival (DSS) according to the preoperative psoas muscle mass index (PMI) and intramuscular adipose tissue content (IMAC) was evaluated. Univariate and multivariate analyses were performed to determine the predictive performance of the covariates with respect to DSS. The DSS rate in patients with high IMAC and low PMI was significantly lower than that in controls. Multivariate analysis revealed that a low preoperative Prognostic Nutritional Index (PNI) and high IMAC were independent risk factors. We demonstrated that preoperative malnutrition and abnormal body composition, such as preoperative skeletal muscle quality, are associated with DSS in OSCC patients. Our study suggests that the evaluation of preoperative malnutrition and skeletal muscle quality would be useful for predicting mortality in patients with OSCC.