Short-Term Effects of Branched-Chain Amino Acids–Enriched Dialysis Fluid on Branched-Chain Amino Acids Plasma Level and Mass Balance: A Randomized Cross-Over Study

Nutritional outcomes between different techniques of intradialytic amino acid replacement: a randomized controlled trial

Background

Amino acid (AA) depletion during dialysis deteriorates the protein-energy status of haemodialysis (HD) patients. This study aimed to determine whether intradialytic amino acid (IDAA) replacement by continuous infusion versus acute load could provide better nutritional outcomes.

Methods

HD patients with mild protein-energy wasting, defined as a serum albumin level of 3.5-3.9 mg/dl despite 7-point subjective global assessment in category A or a malnutrition inflammation score ≤5, were randomly assigned to receive IDAA by continuous infusion or acute load for 3 months. In continuous infusion (n = 24), 50% glucose followed by 7.2% branched-chain enriched AA solution were instilled in the first 15 minutes after HD initiation with high-flux dialyser through the end of the session. Similar parenteral nutrition compositions containing the same total amount of glucose and AA were rapidly added into the venous drip chamber within the last hour of HD in the acute load group (n = 24). The primary outcome was the change in serum albumin level. Secondary outcomes were changes in muscle parameters and plasma as well as dialysate AA concentrations.

Results

The mean age of patients was 68.9 ± 12.7 years and the average body mass index was 22.8 ± 4.4 kg/m2 with 45.8% being men. After 3 months, serum albumin levels were significantly elevated in continuous infusion (P = .001) whereas it was unchanged in the acute load (P = .13). Despite comparable energy and protein intake, total body muscle mass was also increased in the continuous infusion group at 3 months (P = .03) compared with no significant change in the acute load group (P = .45). The amount of AA loss into the dialysate was similar between the two groups (P = .17). At post-dialysis, most plasma essential and non-essential AA levels were significantly lower in patients receiving continuous infusion than acute load, while branched-chain AA concentrations including leucine (P = .61) and valine (P = .09) were comparable between the two groups. Despite enhancing muscle mass in continuous infusion, handgrip strength and gait speed were unaltered in both techniques of IDAA replacement.

Conclusions

IDAA using continuous infusion appears to be superior to acute load in terms of serum albumin and muscle mass improvement. The impact of IDAA on hard clinical outcomes may require larger scale with a longer period of study (TCTR20230401003).

Diagnostic and prognostic value of parameters of erector spinae in patients with uremic sarcopenia

AIM

This study aimed to investigate whether computed tomography (CT)-measured erector spinae parameters (ESPs) have diagnostic, severity assessment, and prognostic predictive value in uremic sarcopenia (US).

MATERIALS AND METHODS

A total of 202 uremic patients were enrolled and divided into two groups: a control group and a sarcopenia group. Sarcopenia was classified into two types: severe and nonsevere. The area, volume, and density of the erector spinae (ES) were measured using chest CT images, and the relevant ESP, including the erector spinae index (ESI), total erector spinae volume (TESV), erector spinae density (ESD), and erector spinae gauge (ESG) were calculated. The occurrence of adverse events was followed-up for 36 months. The diagnostic value and severity of US were determined using the receiver operating characteristic (ROC) curve. Survival curves diagnosed using CT were plotted and compared with the curve drawn using the gold standard. Cox regression analysis was used to identify independent risk factors associated with survival in US.

RESULTS

With an area under the curve (AUC) of 0.840 and 0.739, the combined ESP has diagnostic value and the ability to assess the severity of US. There was no significant difference in the survival curve between the combined ESP for the diagnosis of US and the gold standard (P > 0.05). ESI is a standalone predictor of survival in patients with US.

CONCLUSION

ESP measured by CT has diagnostic values for US and its severity, as well as being a predictive value for the prognosis of US.

Nutritional Strategies to Prevent Muscle Loss and Sarcopenia in Chronic Kidney Disease: What Do We Currently Know?

Loss of muscle mass is an extremely frequent complication in patients with chronic kidney disease (CKD). The etiology of muscle loss in CKD is multifactorial and may depend on kidney disease itself, dialysis, the typical chronic low-grade inflammation present in patients with chronic kidney disease, but also metabolic acidosis, insulin resistance, vitamin D deficiency, hormonal imbalances, amino acid loss during dialysis, and reduced dietary intake. All these conditions together increase protein degradation, decrease protein synthesis, and lead to negative protein balance. Aging further exacerbates sarcopenia in CKD patients. Nutritional therapy, such as protein restriction, aims to manage uremic toxins and slow down the progression of CKD. Low-protein diets (LPDs) and very low-protein diets (VLPDs) supplemented with amino acids or ketoacids are commonly prescribed. Energy intake is crucial, with a higher intake associated with maintaining a neutral or positive nitrogen balance. Adequate nutritional and dietary support are fundamental in preventing nutritional inadequacies and, consequently, muscle wasting, which can occur in CKD patients. This review explores the causes of muscle loss in CKD and how it can be influenced by nutritional strategies aimed at improving muscle mass and muscle strength.

The Potential Modulatory Effects of Exercise on Skeletal Muscle Redox Status in Chronic Kidney Disease

Chronic Kidney Disease (CKD) is a global health burden with high mortality and health costs. CKD patients exhibit lower cardiorespiratory and muscular fitness, strongly associated with morbidity/mortality, which is exacerbated when they reach the need for renal replacement therapies (RRT). Muscle wasting in CKD has been associated with an inflammatory/oxidative status affecting the resident cells' microenvironment, decreasing repair capacity and leading to atrophy. Exercise may help counteracting such effects; however, the molecular mechanisms remain uncertain. Thus, trying to pinpoint and understand these mechanisms is of particular interest. This review will start with a general background about myogenesis, followed by an overview of the impact of redox imbalance as a mechanism of muscle wasting in CKD, with focus on the modulatory effect of exercise on the skeletal muscle microenvironment.

Rehabilitation Nutrition in Patients with Chronic Kidney Disease and Cachexia

Rehabilitation nutrition is a proposed intervention strategy to improve nutritional status and physical function. However, rehabilitation nutrition in patients with cachexia and protein-energy wasting (PEW), which are the main nutrition-related problems in patients with chronic kidney disease (CKD), has not been fully clarified. Therefore, this review aimed to summarize the current evidence and interventions related to rehabilitation nutrition for cachexia and PEW in patients with CKD. CKD is a serious condition worldwide, with a significant impact on patient prognosis. In addition, CKD is easily complicated by nutrition-related problems such as cachexia and PEW owing to disease background- and treatment-related factors, which can further worsen the prognosis. Although nutritional management and exercise therapy are reportedly effective for cachexia and PEW, the effectiveness of combined nutrition and exercise interventions is less clear. In the future, rehabilitation nutrition addressing the nutritional problems associated with CKD will become more widespread as more scientific evidence accumulates. In clinical practice, early intervention in patients with CKD involving both nutrition and exercise after appropriate assessment may be necessary to improve patient outcomes.

Analysis of the Effect of Branched Chain Amino Acids on Muscle Health Information of Swimmers Based on Multisensor Fusion and Deep Learning

Swimmers must fully mobilize the muscles of the whole body during exercise, and it is necessary to study the protection of swimmers from muscle damage. Now, muscle damage is increasing year by year, and more athletes are affected. Therefore, studying the causes of muscle injuries and exploring more effective treatments have become important research topics in the field of sports medicine. This study is mainly based on deep learning to analyze the protective effect of branched-chain amino acids on swimming athletes' muscle injury. Due to the complex and changeable environment and the interference of unknown factors, a single sensor cannot meet the needs of obtaining information. Therefore, people have developed the technology of multisensor information fusion to obtain enough information. Multisensor data fusion technology can synthesize the information of each sensor and then obtain more comprehensive and accurate decision-making information. This study is mainly based on multisensor fusion and deep learning to analyze the impact of branched chain amino acids on Swimmers' muscle health information. Finally, two experiments were designed in this article. The first experimental result showed that the pain level of the experimental group who took BCAA supplements was 19% lower than that of the control group that did not take the BCAA supplement within three days after exercise. The results of the second experiment show the following: after exercise, the creatine kinase activity value of the experimental group taking BCAA supplement was 4.38 ± 1.45, and the creatine kinase activity value of the control group taking placebo was 5.42 ± 2.12. It proves that BBCA can protect muscle damage by reducing the activity of creatine kinase.

Effect of Branched-Chain Amino Acid Infusion on In-Hospital Mortality of Patients With Hepatic Encephalopathy and End-Stage Kidney Disease: A Retrospective Cohort Study Using a National Inpatient Database

OBJECTIVES

Renal failure and hepatic cirrhosis are mutually aggravating factors. However, no specific therapeutic strategies for hepatic encephalopathy (HE) and end-stage kidney disease have been established. The coexistence, with an extremely poor prognosis, makes randomized controlled trials unfeasible. We evaluated whether an infusion of branched-chain amino acids was associated with mortality in patients hospitalized for HE and end-stage kidney disease.

DESIGN AND METHODS

Using the Japanese Diagnosis Procedure Combination database, we retrospectively identified patients with HE and end-stage kidney disease who received hemodialysis within 2 days of admission from July 2011 to March 2017. We divided the patients into those who received branched-chain amino acid infusion within 2 days of admission and those who did not. We conducted analyses using overlap weights based on propensity scores to compare in-hospital mortality between the groups. Sub-group analysis was conducted by stratifying patients by Child-Pugh class.

RESULTS

We identified 553 eligible patients, including 503 patients who received branched-chain amino acid infusion and 50 who did not. The patients who received branched-chain amino acid infusion had lower mortality than those who did not (10.2% vs. 20.1%, relative risk 0.51, 95% confidence interval 0.27-0.95). Sub-group analysis showed that branched-chain amino acid infusion was associated with decreased in-hospital mortality in patients with Child-Pugh class C (16.2% vs. 39.0%, relative risk 0.41, 95% confidence interval 0.23-0.76).

CONCLUSIONS

Branched-chain amino acid infusion may improve the prognosis of HE in patients with end-stage kidney disease, particularly those with lower liver function. Further research is necessary to provide a suitable treatment for HE in patients with end-stage kidney disease.

How to Overcome Anabolic Resistance in Dialysis-Treated Patients?

A current hypothesis is that dialysis-treated patients are "anabolic resistant" i. e., their muscle protein synthesis (MPS) response to anabolic stimuli is blunted, an effect which leads to muscle wasting and poor physical performance in aging and in several chronic diseases. The importance of maintaining muscle mass and MPS is often neglected in dialysis-treated patients; better than to describe mechanisms leading to energy-protein wasting, the aim of this narrative review is to suggest possible strategies to overcome anabolic resistance in this patient's category. Food intake, in particular dietary protein, and physical activity, are the two major anabolic stimuli. Unfortunately, dialysis patients are often aged and have a sedentary behavior, all conditions which per se may induce a state of "anabolic resistance." In addition, patients on dialysis are exposed to amino acid or protein deprivation during the dialysis sessions. Unfortunately, the optimal amount and formula of protein/amino acid composition in supplements to maximixe MPS is still unknown in dialysis patients. In young healthy subjects, 20 g whey protein maximally stimulate MPS. However, recent observations suggest that dialysis patients need greater amounts of proteins than healthy subjects to maximally stimulate MPS. Since unneccesary amounts of amino acids could stimulate ureagenesis, toxins and acid production, it is urgent to obtain information on the optimal dose of proteins or amino acids/ketoacids to maximize MPS in this patients' population. In the meantime, the issue of maintaining muscle mass and function in dialysis-treated CKD patients needs not to be overlooked by the kidney community.

Uremic Sarcopenia and Its Possible Nutritional Approach

Uremic sarcopenia is a frequent condition present in chronic kidney disease (CKD) patients and is characterized by reduced muscle mass, muscle strength and physical performance. Uremic sarcopenia is related to an increased risk of hospitalization and all-causes mortality. This pathological condition is caused not only by advanced age but also by others factors typical of CKD patients such as metabolic acidosis, hemodialysis therapy, low-grade inflammatory status and inadequate protein-energy intake. Currently, treatments available to ameliorate uremic sarcopenia include nutritional therapy (oral nutritional supplement, inter/intradialytic parenteral nutrition, enteral nutrition, high protein and fiber diet and percutaneous endoscopic gastrectomy) and a personalized program of physical activity. The aim of this review is to analyze the possible benefits induced by nutritional therapy alone or in combination with a personalized program of physical activity, on onset and/or progression of uremic sarcopenia.

Dietary protein interventions to improve nutritional status in end-stage renal disease patients undergoing hemodialysis

PURPOSE OF REVIEW

Poor nutritional status is prevalent among end-stage renal disease patients undergoing hemodialysis. Chronic hemodialysis patients show an accelerated decline in skeletal muscle mass and strength, which is associated with higher mortality rates and a reduced quality of life. The current review aims to summarize recent advances regarding underlying causes of muscle loss and interventions that support muscle mass maintenance in patients with chronic hemodialysis.

RECENT FINDINGS

Muscle maintenance in chronic hemodialysis patients is compromised by low dietary protein intake levels, anabolic resistance of skeletal muscle tissue, sedentary behavior, and amino acid removal during hemodialysis. Studies assessing the effect of increased protein intake on nutritional status generally show beneficial results, especially in hypoalbuminemic chronic hemodialysis patients. The muscle protein synthetic response following protein ingestion in chronic hemodialysis patients may be enhanced through incorporation of structured physical activity and/or concurrent ketoacid ingestion.

SUMMARY

A coordinated program that combines nutritional and physical activity interventions is likely required to attenuate the decline in muscle mass and strength of chronic hemodialysis patients. Nephrologists, dieticians, and exercise specialists should collaborate closely to establish guidelines regarding the appropriate quantity and timing of protein ingestion. In addition, they should provide tailored nutritional and physical activity interventions for chronic hemodialysis patients (see video, Supplemental Digital Content 1, Video abstract, http://links.lww.com/COCN/A14).

Sarcopenia in chronic kidney disease: what have we learned so far?

The term sarcopenia was first introduced in 1988 by Irwin Rosenberg to define a condition of muscle loss that occurs in the elderly. Since then, a broader definition comprising not only loss of muscle mass, but also loss of muscle strength and low physical performance due to ageing or other conditions, was developed and published in consensus papers from geriatric societies. Sarcopenia was proposed to be diagnosed based on operational criteria using two components of muscle abnormalities, low muscle mass and low muscle function. This brought awareness of an important nutritional derangement with adverse outcomes for the overall health. In parallel, many studies in patients with chronic kidney disease (CKD) have shown that sarcopenia is a prevalent condition, mainly among patients with end stage kidney disease (ESKD) on hemodialysis (HD). In CKD, sarcopenia is not necessarily age-related as it occurs as a result of the accelerated protein catabolism from the disease and from the dialysis procedure per se combined with low energy and protein intakes. Observational studies showed that sarcopenia and especially low muscle strength is associated with worse clinical outcomes, including worse quality of life (QoL) and higher hospitalization and mortality rates. This review aims to discuss the differences in conceptual definition of sarcopenia in the elderly and in CKD, as well as to describe etiology of sarcopenia, prevalence, outcome, and interventions that attempted to reverse the loss of muscle mass, strength and mobility in CKD and ESKD patients.