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

Frailty in liver transplantation: Exploring prescribing exercise as medicine to improve patient outcomes

Liver transplantation (LT) represents a curative avenue for individuals with advanced chronic liver disease. Given the inherent illness severity of LT candidates, identifying patients at greater risk for adverse outcomes before and after transplantation is paramount. Approximately 50% of cirrhotic patients are frail and have considerable functional impairment. Various measures have been used to assess frailty, including performance-based tests and functional status evaluations. Frailty carries significant prognostic implications and predicts both mortality and pre- and post-LT complications. Contributing factors to frailty in this population include sarcopenia, malnutrition, inflammation, and psychosocial factors. Recognizing the prevalence of frailty among LT candidates, exercise interventions have been developed to improve physical frailty and offer potential to improve patient outcomes. While many interventions have demonstrated efficacy without notable adverse events, the absence of a universally accepted standard for exercise prescription underscores the variability in intervention elements and patient adherence. Given the safety profile of exercise interventions, there remains a critical need for standardized protocols and guidelines to optimize exercise regimens for LT candidates. This review delves into the landscape of frailty among LT candidates, elucidating its etiological underpinnings, impact on outcomes, utilization of exercise interventions, and the efficacy of exercise programs in reducing the burden frailty in those awaiting LT.

The Impact of Metabolic Health and Obesity on Liver Transplant Candidates and Recipients

Poor metabolic health and obesity have significant impacts on the outcomes of patients suffering from chronic liver disease, particularly those with metabolic dysfunction-associated steatotic liver disease. Patients with such comorbidities who require liver transplant evaluation for advancing liver disease or liver failure require special consideration due to increased risk of cardiovascular disease, renal dysfunction, sarcopenic obesity, and cancer. Those who have had a history of prior bariatric surgery pose specific anatomical constraints and may also be at increased risk of alcohol use disorder. Pre-operative risk assessment as well as strict control of metabolic risk factors are essential to reduce intra-operative and post-liver transplant complications. As immunosuppressive therapy exacerbates metabolic dysfunction and risk for cancer, post-liver transplant care must focus on balancing the need to prevent rejection and the impact of progressive metabolic dysfunction in this unique, but growing, patient population.

Frailty in end-stage liver disease: Understanding pathophysiology, tools for assessment, and strategies for management

Frailty and sarcopenia are frequently observed in patients with end-stage liver disease. Frailty is a complex condition that arises from deteriorations across various physiological systems, including the musculoskeletal, cardiovascular, and immune systems, resulting in a reduced ability of the body to withstand stressors. This condition is associated with declined resilience and increased vulnerability to negative outcomes, including disability, hospitalization, and mortality. In cirrhotic patients, frailty is influenced by multiple factors, such as hyperammonemia, hormonal imbalance, malnutrition, ascites, hepatic encephalopathy, and alcohol intake. Assessing frailty is crucial in predicting morbidity and mortality in cirrhotic patients. It can aid in making critical decisions regarding patients' eligibility for critical care and transplantation. This, in turn, can guide the development of an individualized treatment plan for each patient with cirrhosis, with a focus on prioritizing exercise, proper nutrition, and appropriate treatment of hepatic complications as the primary lines of treatment. In this review, we aim to explore the topic of frailty in liver diseases, with a particular emphasis on pathophysiology, clinical assessment, and discuss strategies for preventing frailty through effective treatment of hepatic complications. Furthermore, we explore novel assessment and management strategies that have emerged in recent years, including the use of wearable technology and telemedicine.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Cellular Senescence and Frailty in Transplantation

Purpose of review

To summarizes the literature on cellular senescence and frailty in solid-organ transplantation and highlight the emerging role of senotherapeutics as a treatment for cellular senescence.

Recent findings

Solid-organ transplant patients are aging. Many factors contribute to aging acceleration in this population, including cellular senescence. Senescent cells accumulate in tissues and secrete proinflammatory and profibrotic proteins which result in tissue damage. Cellular senescence contributes to age-related diseases and frailty. Our understanding of the role cellular senescence plays in transplant-specific complications such as allograft immunogenicity and infections is expanding. Promising treatments, including senolytics, senomorphics, cell-based regenerative therapies, and behavioral interventions, may reduce cellular senescence abundance and frailty in patients with solid-organ transplants.

Summary

Cellular senescence and frailty contribute to adverse outcomes in solid-organ transplantation. Continued pursuit of understanding the role cellular senescence plays in transplantation may lead to improved senotherapeutic approaches and better graft and patient outcomes.

Nutrition in intestinal transplantation: centre stage or supporting act?

PURPOSE OF REVIEW

Intestinal transplantation (ITx), whether isolated or combined with other organs, is now a valid treatment option in some patients with chronic intestinal failure or extensive venous mesenteric thrombosis. The aim in these patients is not only to restore nutritional autonomy, but also to minimize the risk of complications, both short and long term. Despite parenteral nutrition playing a central part in the management of intestinal failure patients, there are little data about the perioperative and postoperative nutritional management of ITx patients, due to small patient populations per centre. In this review, we collected the scientific data available to date.

RECENT FINDINGS

In this review, we will bundle the limited scientific information about diet after intestinal and multivisceral transplantation combined with recommendations from our own clinical practice in 28 ITx patients in University Hospitals Leuven, Belgium. We will discuss the immediate preoperative period, surgical complications necessitating dietary interventions and the late postoperative phase in a stable outpatient transplant recipient.

SUMMARY

Although no specific research has been done in the field of ITx, we can extrapolate some findings from other solid organ transplants. Prehabilitation might prove to be of importance; Preserving kidney and liver function in the pretransplant period should be pursued. Transition from parenteral to enteral and oral nutrition can be complex due to inherent surgical procedures and possible complications. Ultimately, the goal is to give patients nutritional autonomy, while also minimizing the risk of foodborne infections by teaching patients well tolerated food practices.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Association of myosteatosis with various body composition abnormalities and longer length of hospitalization in patients with decompensated cirrhosis

Background

Myosteatosis is linked to dismal outcomes in the context of cirrhosis. However, the association of myosteatosis with various body composition abnormalities remains enigmatic. We aimed to clarify the determinants of myosteatosis and its relationship with other body composition profiles and length of hospitalization (LOH).

Methods

We retrospectively analyzed the data of 473 consecutive patients with cirrhosis hospitalized for decompensation. Computed tomography-based segmentation of the cross-sectional area at the third lumbar vertebra was used to evaluate body composition abnormalities. The categories of myosteatosis were built according to our previously outcome-based cutoffs for each gender.

Results

Totally, 83 patients (17.55%) were stratified as myosteatosis, of whom 85.54% had concomitant high visceral adiposity indicative of increased visceral adipose tissue index (VATI). The prevalence of sarcopenia showed no significant difference between the groups with and without myosteatosis. Multivariate analysis showed that advanced age [odds ratio (OR) = 1.097, p < 0.001], higher visceral to subcutaneous ratio of adipose tissue area (VSR; OR = 1.574, p = 0.032), and higher VATI (OR = 1.026, p < 0.001) are independently associated with myosteatosis. Correlation analyses revealed a positive relationship between intramuscular adipose tissue content (IMAC) and VATI (ρ = 0.48, p < 0.001), subcutaneous adipose tissue index (SATI) (ρ = 0.36, p < 0.001), and age (ρ = 0.36, p < 0.001). None of the skeletal muscle or adipose tissue indicators were significantly related to longer LOH.

Conclusion

Higher VSR, higher VATI, and advanced age are associated with myosteatosis among patients with cirrhosis at the decompensation phase. It is tempting to target divergent adipose tissue depots aimed at timely intervention/prevention of myosteatosis.