Factors associated with nutritional status in liver transplant patients who survived the first year after transplantation

Nutritional Intake after Liver Transplant: Systematic Review and Meta-Analysis

Cardiovascular disease and its concurrent risk factors are prevalent after liver transplant (LT). Most of these risk factors are modifiable by diet. We aimed to synthesise the literature reporting the nutritional intake of liver transplant recipients (LTR) and the potential determinants of intake. We performed a systematic review and meta-analyses of studies published up until July 2021 reporting the nutritional intake of LTR. The pooled daily mean intakes were recorded as 1998 (95% CI 1889, 2108) kcal, 17 (17, 18)% energy from protein, 49 (48, 51)% energy from carbohydrates, 34 (33, 35)% energy from total fat, 10 (7, 13)% energy from saturated fat, and 20 (18, 21) g of fibre. The average fruit and vegetable intake ranged from 105 to 418 g/day. The length of time post-LT and the age and sex of the cohorts, as well as the continent and year of publication of each study, were sources of heterogeneity. Nine studies investigated the potential determinants of intake, time post-LT, gender and immunosuppression medication, with inconclusive results. Energy and protein requirements were not met in the first month post-transplant. After this point, energy intake was significantly higher and remained stable over time, with a high fat intake and low intake of fibre, fruits and vegetables. This suggests that LTR consume a high-energy, low-quality diet in the long term and do not adhere to the dietary guidelines for cardiovascular disease prevention.

Main factors influencing long-term outcomes of liver transplantation in 2022

Liver transplant (LT) outcomes have markedly improved in the recent decades, even if long-term morbidity and mortality are still considerable. Most of late deaths are independent from graft function and different comorbidities, including complications of metabolic syndrome and de novo neoplasms, seem to play a key role in determining long-term outcomes in LT recipients. This review discusses the main factors associated with late mortality and suggests possible strategies to improve long-term management and follow-up after liver transplantation. In particular, the reduction of drug toxicity, the use of tools to identify high-risk patients, and setting up a multidisciplinary team also for long-term management of LT recipients may further improve survival after liver transplantation.

Predictors of solid extra-hepatic non-skin cancer in liver transplant recipients and analysis of survival: A long-term follow-up study

INTRODUCTION AND OBJECTIVES

De novo malignancies represent an important cause of death for liver transplant recipients. Our aim was to analyze predictors of extra-hepatic non-skin cancer (ESNSC) and the impact of ESNSC on the long-term outcome.

PATIENTS

We examined data from patients transplanted between 2000 and 2005 and followed-up in five Italian transplant clinics with a retrospective observational cohort study. Cox Regression was performed to identify predictors of ESNSC. A 1:2 cohort sub-study was developed to analyze the impact of ESNSC on 10-year survival.

RESULTS

We analyzed data from 367 subjects (median follow-up: 15 years). Patients with ESNSC (n = 47) more often developed post-LT diabetes mellitus (DM) (57.4% versus 35,9%, p = 0.004). At multivariate analysis, post-LT DM independently predicted ESNSC (HR 1.929, CI 1.029-3.616, p = 0.040). Recipients with ESNSC showed a lower 10-year survival than matched controls (46,8% versus 68,1%, p = 0.023).

CONCLUSIONS

Post-LT DM seems to be a relevant risk factor for post-LT ESNSC. ESNSC could have a noteworthy impact on the long-term survival of LT recipients.

Metabolic Disorders After Liver Transplantation

Early after surgery, liver transplant (LT) recipients often develop weight gain due to an increase of caloric intake and fat mass (without recovery of muscle frame). This modification of body composition together with a negative metabolic impact of immunosuppressive drugs leads to a high prevalence of all the main metabolic disorders. Indeed, as expected, transplanted patients show a higher cardiovascular risk in comparison with general population. Notably, seeing the increase of mean age of transplanted population, metabolic disorders represent the true challenge for the transplant community. Considering the lack of evidences or clear indications about prevention, early diagnosis and treatment of metabolic disorders after LT, it would be mandatory to develop targeted further studies on this matter.

Pre-transplant diabetes predicts atherosclerotic vascular events and cardiovascular mortality in liver transplant recipients: a long-term follow-up study

Background Early after surgery, liver transplant (LT) recipients often develop weight gain. Metabolic disorders and cardiovascular disease represent main drivers of morbidity and mortality. Our aim was to identify predictors of atherosclerotic vascular events (AVE) and to assess the impact of AVE on the long-term outcome. Methods We retrospectively analyzed data from patients transplanted between 2000 and 2005 and followed-up in five Italian transplant clinics. Cox Regression analysis was performed to identify predictors of AVE, global mortality, and cardiovascular mortality. Survival analysis was performed using the Kaplan-Meier method. Results We analyzed data from 367 subjects during a median follow-up of 14 years. Thirty-seven post-LT AVE were registered. Patients with AVE more frequently showed pre-LT diabetes mellitus (DM) (48.6 vs 13.9%, p=0.000). In the post-LT period, patients with AVE satisfied criteria of metabolic syndrome in 83.8% vs. 36.7% of subjects without AVE (p=0.000). At multivariate analysis, pre-LT DM independently predicted AVE (HR 2.250, CI 4.848-10.440, p=0.038). Moreover, both pre-LT DM and AVE strongly predicted cardiovascular mortality (HR 5.418, CI 1.060-29.183, p=0.049, and HR 86.097, CI 9.510-779.480, p=0.000, respectively). Conclusions Pre-LT DM is the main risk factor for post-LT AVE. Pre-LT DM and post-LT AVE are strong, long-term predictors of cardiovascular mortality. Patients with pre-LT DM should obtain a personalized follow-up for prevention or early diagnosis of AVE.

[Nutritional Status of Liver Transplantation Recipients and Factors Influencing Nutritional Status]

PURPOSE

This study aimed to investigate the nutritional status of liver transplantation (LT) recipients and explore certain factors that influence nutritional status, including dietary patterns and physical activities.

METHODS

This was a cross-sectional, descriptive study. The subjects included 211 LT recipients at a medical center outpatient clinic located in Seoul, Korea. The nutritional status, dietary patterns, and physical activities of each subject were measured using the body mass index (BMI), Mini Dietary Assessment (MDA), and Global Physical Activity Questionnaire. Independent t-test, one-way analysis of variance, and multiple linear regression analysis were used to analyze the data.

RESULTS

The percentages of living and deceased donor LTs were 81.0% and 19.0%, respectively. The mean BMIs pre- and post-LT were 23.88 and 23.16 kg/m², respectively, and the average MDA score was 36.55. More than 60.0% of the subjects had a moderate or high level of physical activity. In multivariate analysis, a higher BMI before LT (β=.72, p<.001), a lower Model for End-stage Liver Disease (MELD) score (β=-.18, p<.001), and being male (β=-.10, p=.024) contributed to better nutritional status post-LT. Patients within six months of LT were less engaged in muscle exercises than those post six months of LT (p=.020).

CONCLUSION

LT recipients in Korea have good nutritional status and a good level of physical activity. To improve recipients' post-LT nutritional status, the pre-LT nutritional status should be considered, particularly in those with a higher MELD score. In addition, physical activity including muscle-strengthening exercises should be encouraged from an earlier stage.

De-novo nonalcoholic steatohepatitis is associated with long-term increased mortality in liver transplant recipients

OBJECTIVE

Patients who have undergone transplantation often develop metabolic syndrome (MetS) and de-novo nonalcoholic fatty liver disease (NAFLD). Our aim was to evaluate the impact of metabolic disease on cardiovascular and neoplastic risk and survival.

PATIENTS AND METHODS

Data from patients who underwent transplantation between 2000 and 2005 in two Italian transplant centers were analyzed. Cox regression analysis was carried out for predictors of de-novo NAFLD and nonalcoholic steatohepatitis (NASH), cardiovascular events, de-novo extrahepatic cancers, and survival. Survival analysis was completed using the Kaplan-Meier method. A P value less than 0.05 was considered significant for all tests.

RESULTS

De-novo NAFLD was found in one-fifth of 194 patients. Patients with de-novo NAFLD fulfilled the criteria of MetS in 74.4% of cases, while patients without de-novo NAFLD in 29.8% (P=0.000). On multivariate analysis, MetS correlated independently with de-novo NAFLD and this emerged as an independent predictor of cardiovascular events and as a relevant risk factor for solid extrahepatic cancer. Data on smoking habits, which represent a consolidated risk factor for cardiovascular events and cancer in both the general population and patients who have undergone transplantation, are not available. In the subset of histologically proven NASH, it was the strongest predictor of long-term survival (hazard ratio=4.133, 95% confidence interval: 1.385-12.331, P=0.011).

CONCLUSION

Post-transplant NAFLD represented a strong risk factor for cardiovascular atherosclerotic disease and solid extrahepatic cancer, whereas de novo histologically proven NASH was an independent predictor of long-term mortality.

Nutrition and Muscle in Cirrhosis

As the cirrhosis progresses, development of complication like ascites, hepatic encephalopathy, variceal bleeding, kidney dysfunction, and hepatocellular carcinoma signify increasing risk of short term mortality. Malnutrition and muscle wasting (sarcopenia) is yet other complications that negatively impact survival, quality of life, and response to stressors, such as infection and surgery in patients with cirrhosis. Conventionally, these are not routinely looked for, because nutritional assessment can be a difficult especially if there is associated fluid retention and/or obesity. Patients with cirrhosis may have a combination of loss of skeletal muscle and gain of adipose tissue, culminating in the condition of "sarcopenic obesity." Sarcopenia in cirrhotic patients has been associated with increased mortality, sepsis complications, hyperammonemia, overt hepatic encephalopathy, and increased length of stay after liver transplantation. Assessment of muscles with cross-sectional imaging studies has become an attractive index of nutritional status evaluation in cirrhosis, as sarcopenia, the major component of malnutrition, is primarily responsible for the adverse clinical consequences seen in patients with liver disease. Cirrhosis is a state of accelerated starvation, with increased gluconeogenesis that requires amino acid diversion from other metabolic functions. Protein homeostasis is disturbed in cirrhosis due to several factors such as hyperammonemia, hormonal, and cytokine abnormalities, physical inactivity and direct effects of ethanol and its metabolites. New approaches to manage sarcopenia are being evolved. Branched chain amino acid supplementation, Myostatin inhibitors, and mitochondrial protective agents are currently in various stages of evaluation in preclinical studies to prevent and reverse sarcopenia, in cirrhosis.

The importance of nutrition for pediatric liver transplant patients

Pediatric liver transplantation has changed the poor prognosis for children with liver failure, some metabolic diseases and liver tumors. With the increase of survival, long-term maintenance has become a priority. Therefore, obtaining appropriate nutrition, physical growth, bone metabolism, endocrine function and psychosocial development has become one of the most important long-term objectives. This article presents an up-to-date review and recommendation of nutrition assessment, both before and after liver transplantation.

Evaluation of Malnutrition Risk after Liver Transplantation Using the Nutritional Screening Tools

Malnutrition is a common problem in patients with end-stage liver disease requiring liver transplantation. The aim of this study was to evaluate nutritional status by using nutritional screening tools [Nutritional Risk Screening (NRS) 2002, Malnutrition Universal Screening Tool (MUST) and Subjective Global Assessment (SGA)] in patients before and after liver transplantation. We analyzed medical record, blood test, nutrient intake and malnutrition rate just before transplantation and at discharge, and at 3, 6, 12 months after transplantation respectively. Initially 33 patients enrolled as study subjects and finally 28 patients completed the study. Nutrients intake such as energy, fiber, calcium, potassium, vitamin C, and folate were insufficient at 12 months after transplantation. The rates of malnutrition before transplantation were very high, reported at 81.8% for the NRS 2002, 87.9% for the MUST, and 84.8% for the SGA. By 12 months after operation, malnutrition rates reported at NRS, MUST and SGA had decreased to 6.1%, 10.7%, and 10.7%, respectively. Sensitivity was 87.1% for the NRS 2002, 82.0% for the MUST, and 92.0% for the SGA. Of these screening tools the SGA was the highest sensitive tool that predict the risk of mortality in malnutrition patients who received transplantation. Further studies on nutritional status of patients and proper tools for nutrition intervention are needed to provide adequate nutritional care for patients.

Changes in nutritional status after liver transplantation

Chronic liver disease has an important effect on nutritional status, and malnourishment is almost universally present in patients with end-stage liver disease who undergo liver transplantation. During recent decades, a trend has been reported that shows an increase in number of patients with end-stage liver disease and obesity in developed countries. The importance of carefully assessing the nutritional status during the work-up of patients who are candidates for liver replacement is widely recognised. Cirrhotic patients with depleted lean body mass (sarcopenia) and fat deposits have an increased surgical risk; malnutrition may further impact morbidity, mortality and costs in the post-transplantation setting. After transplantation and liver function is restored, many metabolic alterations are corrected, dietary intake is progressively normalised, and lifestyle changes may improve physical activity. Few studies have examined the modifications in body composition that occur in liver recipients. During the first 12 mo, the fat mass progressively increases in those patients who had previously depleted body mass, and the muscle mass recovery is subtle and non-significant by the end of the first year. In some patients, unregulated weight gain may lead to obesity and may promote metabolic disorders in the long term. Careful monitoring of nutritional changes will help identify the patients who are at risk for malnutrition or over-weight after liver transplantation. Physical and nutritional interventions must be investigated to evaluate their potential beneficial effect on body composition and muscle function after liver transplantation.

Posttransplant sarcopenia: an underrecognized early consequence of liver transplantation

Liver transplantation is believed to reverse the clinical and metabolic abnormalities of cirrhosis. Reduced skeletal muscle mass or sarcopenia contributes to increased mortality and adverse consequences of cirrhosis. Failure of reversal of sarcopenia of cirrhosis after liver transplantation is not well recognized. Six temporally, geographically, and methodologically distinct follow-up studies in 304 cirrhotics reported conflicting data on changes in indirect measures of skeletal muscle mass after transplantation. Distinct measures of body composition but not skeletal muscle mass were used and did not focus on the clinical consequences of sarcopenia after transplantation. A number of studies reported an initial rapid postoperative loss of lean mass followed by incomplete recovery with a maximum follow-up of 2 years. Posttransplant sarcopenia may be responsible for metabolic syndrome and impaired quality of life after liver transplantation. Potential reasons for failure to reverse sarcopenia after liver transplantation include use of immunosuppressive agents [mammalian target of rapamycin (mTOR) and calcineurin inhibitors] that impair skeletal muscle growth and protein accretion. Repeated hospitalizations, posttransplant infections, and renal failure also contribute to posttransplant sarcopenia. Finally, recovery from muscle deconditioning is limited by lack of systematic nutritional and physical-activity-based interventions to improve muscle mass. Despite the compelling data on sarcopenia before liver transplantation, the impact of posttransplant sarcopenia on clinical outcomes is not known. There is a compelling need for studies to examine the mechanisms and consequences of sarcopenia post liver transplantation to permit development of therapies to prevent and reverse this disorder.

Malnutrition in cirrhosis: contribution and consequences of sarcopenia on metabolic and clinical responses

Malnutrition is the most common, reversible complication of cirrhosis that adversely affects survival, response to other complications, and quality of life. Sarcopenia, or loss of skeletal muscle mass, and loss of adipose tissue and altered substrate use as a source of energy are the 2 major components of malnutrition in cirrhosis. Current therapies include high protein supplementation especially as a late evening snack. Exercise protocols have the potential of aggravating hyperammonemia and portal hypertension. Recent advances in understanding the molecular regulation of muscle mass has helped identify potential novel therapeutic targets including myostatin antagonists, and mTOR resistance.

Nutritional status and liver transplantation

Chronic liver disease has a profound effect on nutritional status and undernourishment is almost universally present in patients with end-stage liver disease undergoing liver transplantation. In the last decades, due to epidemiological changes, a trend showing an increase in patients with end-stage liver disease and associated obesity has also been reported in developed countries. Nutrition abnormalities may influence the outcome after transplantation therefore, the importance to carefully assess the nutritional status in the work-up of patients candidates for liver transplantation is widely accepted. More attention has been given to malnourished patients as they represent the greater number. The subjective global nutritional assessment and anthropometric measurements are recognized in current guidelines to be adequate in identifying those patients at risk of malnutrition. Cirrhotic patients with a depletion in lean body mass and fat deposits have an increased surgical risk and malnutrition may impact on morbidity, mortality and costs in the post-transplantation setting. For this reason an adequate calorie and protein intake should always be ensured to malnourished cirrhotic patient either through the diet, or using oral nutritional supplements or by enteral or parenteral nutrition although studies supporting the efficacy of nutritional supplementation in improving the clinical outcomes after transplantation are still scarce. When liver function is restored, an amelioration in the nutritional status is expected. After liver transplantation in fact dietary intake rapidly normalizes and fat mass is progressively regained while the recovery of muscle mass can be slower. In some patients unregulated weight gain may lead to over-nutrition and may favor metabolic disorders (hypertension, hyperglycemia, hyperlipidemia). This condition, defined as 'metabolic syndrome', may play a negative role on the overall survival of liver transplant patients. In this report we review data on nutrition and liver transplantation.

Contribution of anorexia to tissue wasting in cachexia

PURPOSE OF REVIEW

Anorexia is a severe debilitating symptom characterizing the clinical course of several chronic diseases. It negatively impacts on patient outcome by contributing to weight loss, lean body mass catabolism and adipose tissue wasting. Although disease-associated anorexia may stand alone as a clinically relevant symptom, it is now considered as a component of the cachexia syndrome. The present review discusses experimental and clinical data indicating that the pathogenic mechanisms of anorexia may also suggest a neural control of tissue wasting in cachexia.

RECENT FINDINGS

Consistent data show that selective melanocortin receptor antagonism modulates food intake and reduces wasting in experimental models of chronic disease. Consequently, ghrelin administration, whose prophagic effects are related to melanocortin antagonism, has been tested both in animal studies and human trials, with promising effects, although restoration of lean body mass has been not achieved. More interest is driven by the use of small molecules selectively antagonising hypothalamic melanocortin receptors.

SUMMARY

The 'brain-muscle axis' coordinated by the hypothalamus seems to mediate the onset of not only anorexia but also tissue wasting in cachexia, by centrally influencing energy homeostasis and the balance between anabolism and catabolism.