How to cultivate sustainable physical health and wellness in transplant recipients: the emerging and enduring role of exercise scientists.

PURPOSE OF REVIEW: The aim of the current review is to highlight the importance of exercise training as an important section of transplant recipient rehabilitation process and explain the role of the exercise scientist in the development, implementation, and assessment of the exercise regime. RECENT FINDINGS: Transplant patients face a unique set of challenges in their recovery and rehabilitation process, often requiring a multifaceted approach to address the physical, emotional, and psychological aspects of their condition. Exercise training has emerged as a crucial component in the care of these patients, providing a means to improve functional capacity, enhance quality of life, and mitigate the adverse effects of transplant-related complications. Exercise scientists who are trained to assess patient's physical limitations, develop and deliver personalized exercise programs, and monitor their progress are uniquely positioned to play a crucial role in the treatment of patients with chronic conditions that require exercise training as a mean of improving and maintaining health and quality of life. SUMMARY: Exercise scientists are the appropriate professionals for providing transplant recipients with the recommended exercise training for maintaining and improving their health status as part of the overall plan of long-term care and support.

Subjective Thirst in Relation to Interdialytic Weight Gain: A Systematic Review of Observational Studies.

INTRODUCTION: Hemodialysis (HD) patients are often prescribed salt and fluid-restricted diets to reduce their interdialytic weight gain (IDWG) and prevent chronic volume overload and hypertension. However, adherence to fluid restrictions is poor, which may be due to HD patients' excessive thirst. The purpose of the review is to explore the association between HD patients' subjective thirst and IDWG, which may inform strategies to manage chronic volume overload. METHODS: We conducted the literature search in Web of Science, Cumulative Index to Nursing and Allied Health Literature, PubMed, and the Cochrane Library, until February 25, 2019. Studies performing statistical tests to assess the association between patients' subjective thirst and IDWG were included. RESULTS: A total of eighteen studies were included in the systematic review, which measured the relationship between patients' subjective thirst and IDWG. Among them, 14 studies found that different domains of thirst and different units of IDWG are positively associated. Therefore, there is a positive association between the patients' subjective thirst and IDWG. However, the findings should be interpreted cautiously as there was variability in thirst and IDWG measurement techniques, which might influence the estimated relationship in these studies. DISCUSSION/CONCLUSION: These data suggest that strategies are needed to reduce thirst to control IDWG in HD patients.

The effect of intradialytic exercise on calcium, phosphorus and parathyroid hormone: a randomized controlled trial.

BACKGROUND: Patients with kidney failure experience derangements of circulating markers of mineral metabolism and dysregulation of skeletal and cardiovascular physiology which results in high mortality rate in these patients. This study aimed to evaluate the effect of intradialytic exercise on regulation of these abnormalities in patients receiving chronic hemodialysis (HD). METHODS: In this randomized controlled trial conducted in an HD center in Iran, adult patients receiving chronic HD were randomized to intradialytic exercise (60 min) in the second hour of thrice weekly dialysis for 6 months (intervention) or no intradialytic exercise (control). The primary outcomes were serum calcium, serum phosphorous and parathyroid hormone levels. Secondary outcomes were serum alkaline phosphatase and calcium-phosphorous product. RESULTS: The study included 44 participants randomized to intervention (n = 22) or control (n = 22). During the 6-month intervention period, significant between-group changes were observed in all primary and secondary outcomes between the intervention and control groups. Statistical analyses reveal a significant increase in serum calcium (P < 0.05) as well as a significant decrease in serum phosphorous, parathyroid hormone, alkaline phosphatase and calcium-phosphorous product (P < 0.05). CONCLUSION: Intradialytic exercise performed for at least 60 min during thrice weekly dialysis sessions improves bone mineral metabolism in adult patients receiving HD. Further studies should focus on observing and comparing the effect of different types of exercise on bone mineral disorders and all-cause mortality in HD patients. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04916743, Registered on 08/06/2021. Registered trial name: The Effect of Intradialytic Exercise on Calcium, Phosphorous and Parathyroid Hormone: A Randomized Controlled Trial.

Muscle Sodium Accumulation in Kidney Failure: Physiological Impact and Mitigation Strategies.

Skeletal muscle has recently been recognized as a nonosmotic sodium reservoir that buffers dietary sodium. The in-vivo quantification of muscle sodium is based on a novel technology, sodium magnetic resonance imaging. Studies using this technology have shown that muscle sodium accumulation may be a clinical complication of chronic kidney disease (CKD). This review aims to summarize existing evidence on muscle sodium accumulation in patients with CKD and to identify knowledge gaps and topics for further research. The literature examined in this review suggests that muscle sodium accumulation is associated with CKD progression and pathological conditions. However, the causalities between muscle sodium accumulation and its related pathological changes are still elusive mainly because it is still uncertain where and how sodium accumulates in the muscle. More research is needed to address these gaps and determine if muscle sodium is a new intervention target in CKD.

Advanced Glycation End Products and Inflammatory Cytokine Profiles in Maintenance Hemodialysis Patients After the Ingestion of a Protein-Dense Meal.

OBJECTIVE: The goal of this investigation was to evaluate circulating and skeletal muscle inflammatory biomarkers between maintenance hemodialysis (MHD) and demographic-matched control subjects (CON) before and after ingestion of a protein-rich meal. DESIGN AND METHODS: CON (n = 8; 50 ± 2 years; 31 ± 1 kg/m2) and MHD patients (n = 8; 56 ± 5 years; 32 ± 2 kg/m2) underwent a basal blood draw and muscle biopsy and serial blood draws after the ingestion of a mixed meal on a nondialysis day. Plasma advanced glycation end products (AGEs) and markers of oxidation were assessed via liquid chromatography-tandem mass spectrometry before and after the meal (+240 min). Circulating inflammatory cytokines and soluble receptors for AGE (sRAGE) isoforms (endogenous secretory RAGEs and cleaved RAGEs) were determined before and after the meal (+240 min). Basal muscle was probed for inflammatory cytokines and protein expression of related signaling components (RAGE, Toll-like receptor 4, oligosaccharyltransferase subunit 48, TIR-domain-containing adapter-inducing interferon-ß, total IκBα, and pIκBα). RESULTS: Basal circulating AGEs were 7- to 343-fold higher (P < .001) in MHD than those in CON, but only MG-H1 increased in CON after the meal (P < .001). There was a group effect (MHD > CON) for total sRAGEs (P = .02) and endogenous secretory RAGEs (P < .001) and a trend for cleaved RAGEs (P=.09), with no meal effect. In addition, there was a group effect (MHD < CON; P < .05) for circulating fractalkine, interleukin (IL)10, IL17A, and IL1ß and a trend (P < .10) for IL6 and macrophage inflammatory protein 1 alpha, whereas tumor necrosis factor alpha was higher in MHD (P < .001). In muscle, Toll-like receptor 4 (P = .03), TIR-domain-containing adapter-inducing interferon-ß (P = .002), and oligosaccharyltransferase subunit 48 (P = .02) expression was lower in MHD than that in CON, whereas IL6 was higher (P = .01) and IL8 (P = .08) tended to be higher in MHD. CONCLUSION: Overall, MHD exhibited an exaggerated, circulating, and skeletal muscle inflammatory biomarker environment, and the meal did not appreciably affect the inflammatory status.

Exercise in Dialysis: Ready for Prime Time?

It is widely acknowledged that patients with end-stage kidney disease receiving maintenance hemodialysis (HD) may benefit from increasing their physical activity levels. Decades of exercise-related clinical trials have demonstrated improvements in various metrics related to dialysis patient's health and quality of life. Yet, the implementation of exercise programs in dialysis clinics today is scarce, and physical inactivity and dysfunction remain a hallmark of the disease. To address this issue, many groups worldwide are beginning to rethink how physical activity and exercise are prescribed in HD patients, as well as how to evaluate the efficacy of these programs. The vast majority of exercise interventions in HD patients have included intradialytic cycling as the predominant or only exercise prescription. Moreover, efficacy has most often been evaluated using standard measures of strength, physical function, and/or traditional cardiovascular disease risk factors (e.g., blood pressure, lipids, etc.). More recently, there has been a greater emphasis on novel intervention approaches that are focused on providing patients with a greater variety of options for exercise and enhanced motivational tools. The benefits of exercise on patient reported outcome measures (PROMs) and other clinically important outcomes are also becoming more prevalent. The purpose of this review was to: (1) critically review the data from several recently published large randomized clinical trials of exercise in HD patients, (2) discuss some of the novel approaches that groups across the world are taking to improve implementation and efficacy of exercise-related interventions in HD, and (3) discuss policy prescriptions that may be needed to continue improving exercise prescriptions for this critically ill patient population. While it may be too early to declare that exercise in dialysis is ready for prime time, exciting advances have been made in recent years, yet more work is needed to realize its full potential.

A Comparison of Dietary Intake Between Individuals Undergoing Maintenance Hemodialysis in the United Kingdom and China.

OBJECTIVE: Protein-energy wasting is highly prevalent in people with end-stage kidney disease receiving regular hemodialysis. Currently, it is unclear what the optimal nutritional recommendations are, which is further complicated by differences in dietary patterns between countries. The aim of the study was to understand and compare dietary intake between individuals receiving hemodialysis in Leicester, UK and Nantong, China. METHODS: The study assessed 40 UK and 44 Chinese participants' dietary intake over a period of 14 days using 24-hour diet recall interviews. Nutritional blood parameters were obtained from medical records. Food consumed by participants in the UK and China was analyzed using the Nutritics and Nutrition calculator to quantify nutritional intake. RESULTS: Energy and protein intake were comparable between UK and Chinese participants, but with both below the recommended daily intake. Potassium intake was higher in UK participants compared to Chinese participants (2,115 [888] versus 1,159 [861] mg/d; P < .001), as was calcium (618 [257] versus 360 [312] mg/d; P < .001) and phosphate intake (927 [485] versus 697 [434] mg/d; P = .007). Vitamin C intake was lower in UK participants compared to their Chinese counterparts (39 [51] versus 64 [42] mg/d; P = .024). Data are reported here as median (interquartile range). CONCLUSION: Both UK and Chinese hemodialysis participants have insufficient protein and energy in their diet. New strategies are required to increase protein and energy intakes. All participants had inadequate daily intake of vitamins C and D; there may well be a role in the oral supplementation of these vitamins, and further studies are urgently needed.

Global Policy Barriers and Enablers to Exercise and Physical Activity in Kidney Care.

OBJECTIVE: Impairment in physical function and physical performance leads to decreased independence and health-related quality of life in people living with chronic kidney disease and end-stage kidney disease. Physical activity and exercise in kidney care are not priorities in policy development. We aimed to identify global policy-related enablers, barriers, and strategies to increase exercise participation and physical activity behavior for people living with kidney disease. DESIGN AND METHODS: Guided by the Behavior Change Wheel theoretical framework, 50 global renal exercise experts developed policy barriers and enablers to exercise program implementation and physical activity promotion in kidney care. The consensus process consisted of developing themes from renal experts from North America, South America, Continental Europe, United Kingdom, Asia, and Oceania. Strategies to address enablers and barriers were identified by the group, and consensus was achieved. RESULTS: We found that policies addressing funding, service provision, legislation, regulations, guidelines, the environment, communication, and marketing are required to support people with kidney disease to be physically active, participate in exercise, and improve health-related quality of life. We provide a global perspective and highlight Japanese, Canadian, and other regional examples where policies have been developed to increase renal physical activity and rehabilitation. We present recommendations targeting multiple stakeholders including nephrologists, nurses, allied health clinicians, organizations providing renal care and education, and renal program funders. CONCLUSIONS: We strongly recommend the nephrology community and people living with kidney disease take action to change policy now, rather than idly waiting for indisputable clinical trial evidence that increasing physical activity, strength, fitness, and function improves the lives of people living with kidney disease.

Depressive Disorders Are Associated With Risk of Falls in People With Chronic Kidney Disease.

OBJECTIVES: People with chronic kidney disease (CKD) are at increased risk for falls and fall-related injuries. Depressive disorders (DEP) are common in individuals with CKD and may increase the risk of falls and fall-related injuries. However, not much is known about the relationship between DEP and falls in people with CKD. The purpose of this study was to determine the influence of DEP on the relationship between CKD, falls, and fall-related injuries. METHOD: Using the Behavioral Risk Factor Surveillance System, we identified 16,574 adults with CKD. Patients with CKD were stratified by history of self-reported DEP (SRDEP), and multivariate logistic regression was conducted to determine the odds for falls and fall-related injuries among those with and without SRDEP. RESULTS: In unadjusted regression analysis, falls (OR = 2.40, 95% CI = 2.08-2.76) and fall-related injuries (OR = 2.12, 95% CI = 1.72-2.59) were higher in individuals with CKD and history of SRDEP compared to those with CKD and no history of SRDEP. Adjustment for confounders had little effect on the relationship between a history of SRDEP and either falls (AOR = 1.87, 95% CI = 1.60-2.19) or fall-related injuries (AOR = 1.58, 95% CI = 1.26-1.97). CONCLUSIONS: People with CKD and DEP are at increased odds for falls and fall-related injuries even after adjustment for sociodemographic, lifestyle factors, and comorbidities. Prospective studies are warranted to further understand this relationship, but it may be prudent for clinicians, in particular nurses, to consider fall risk when treating DEP in patients with CKD.

Muscle-Bone Crosstalk in Chronic Kidney Disease: The Potential Modulatory Effects of Exercise.

Chronic kidney disease (CKD) is a prevalent worldwide public burden that increasingly compromises overall health as the disease progresses. Two of the most negatively affected tissues are bone and skeletal muscle, with CKD negatively impacting their structure, function and activity, impairing the quality of life of these patients and contributing to morbidity and mortality. Whereas skeletal health in this population has conventionally been associated with bone and mineral disorders, sarcopenia has been observed to impact skeletal muscle health in CKD. Indeed, bone and muscle tissues are linked anatomically and physiologically, and together regulate functional and metabolic mechanisms. With the initial crosstalk between the skeleton and muscle proposed to explain bone formation through muscle contraction, it is now understood that this communication occurs through the interaction of myokines and osteokines, with the skeletal muscle secretome playing a pivotal role in the regulation of bone activity. Regular exercise has been reported to be beneficial to overall health. Also, the positive regulatory effect that exercise has been proposed to have on bone and muscle anatomical, functional, and metabolic activity has led to the proposal of regular physical exercise as a therapeutic strategy for muscle and bone-related disorders. The detection of bone- and muscle-derived cytokine secretion following physical exercise has strengthened the idea of a cross communication between these organs. Hence, this review presents an overview of the impact of CKD in bone and skeletal muscle, and narrates how these tissues intrinsically communicate with each other, with focus on the potential effect of exercise in the modulation of this intercommunication.

Association between physical activity and mortality in end-stage kidney disease: a systematic review of observational studies.

BACKGROUND: End-stage Kidney Disease patients have a high mortality and hospitalization risk. The association of these outcomes with physical activity is described in the general population and in other chronic diseases. However, few studies examining this association have been completed in end-stage Kidney Disease patients, raising the need to systematically review the evidence on the association of physical activity with mortality and hospitalization in this population. METHODS: Electronic databases (EBSCO, Scopus and Web of Science) and hand search were performed until March 2020 for observational studies reporting the association of physical activity with mortality or hospitalization in adult end-stage Kidney Disease patients on renal replacement therapy (hemodialysis, peritoneal dialysis and kidney transplant). Methodological quality of the included studies was assessed using the Quality in Prognosis Studies tool. The review protocol was registered in PROSPERO (CRD42020155591). RESULTS: Eleven studies were included: six in hemodialysis, three in kidney transplant, and two in hemodialysis and peritoneal dialysis patients. Physical activity was self-reported, except in one study that used accelerometers. All-cause mortality was addressed in all studies and cardiovascular mortality in three studies. Nine studies reported a significant reduction in all-cause mortality with increased levels of physical activity. Evidence of a dose-response relationship was found. For cardiovascular mortality, a significant reduction was observed in two of the three studies. Only one study investigated the association of physical activity with hospitalization. CONCLUSIONS: Higher physical activity was associated with reduced mortality in end-stage Kidney Disease patients. Future studies using objective physical activity measures could strengthen these findings. The association of physical activity with hospitalization should be explored in future investigations.

Effect of Dietary Inulin Supplementation on the Gut Microbiota Composition and Derived Metabolites of Individuals Undergoing Hemodialysis: A Pilot Study.

OBJECTIVE: The prebiotic fiber inulin has been studied in individuals undergoing hemodialysis (HD) due to its ability to reduce gut microbiota-derived uremic toxins. However, studies examining the effects of inulin on the gut microbiota and derived metabolites are limited in these patients. We aimed to assess the impact of a 4-week supplementation of inulin on the gut microbiota composition and microbial metabolites of patients on HD. DESIGN AND METHODS: In a randomized, double-blind, placebo-controlled, crossover study, twelve HD patients (55 ± 10 y, 50% male, 58% Black American, BMI 31.6 ± 8.9 kg/m2, 33% diabetes mellitus) were randomized to consume inulin [10 g/d for females; 15 g/d for males] or maltodextrin [6 g/d for females; 9 g/d for males] for 4 weeks, with a 4-week washout period. We assessed the fecal microbiota composition, fecal metabolites (short-chain fatty acids (SCFA), phenols, and indoles), and plasma indoxyl sulfate and p-cresyl sulfate. RESULTS: At baseline, factors that explained the gut microbiota variability included BMI category and type of phosphate binder prescribed. Inulin increased the relative abundance of the phylum Verrucomicrobia and its genus Akkermansia (P interaction = 0.045). Inulin and maltodextrin resulted in an increased relative abundance of the phylum Bacteroidetes and its genus Bacteroides (P time = 0.04 and 0.03, respectively). Both treatments increased the fecal acetate and propionate (P time = 0.032 and 0.027, respectively), and there was a trend toward increased fecal butyrate (P time = 0.06). Inulin did not reduce fecal p-cresol or indoles, or plasma concentrations of p-cresyl sulfate or indoxyl sulfate. CONCLUSIONS: A 4-week supplementation of inulin did not lead to major shifts in the fecal microbiota and gut microbiota-derived metabolites. This may be due to high variability among participants and an unexpected increase in fecal excretion of SCFA with maltodextrin. Larger studies are needed to determine the effects of prebiotic fibers on the gut microbiota and clinical outcomes to justify their use in patients on HD.

Working on Wellness: Impact of a Pilot Workplace Wellness Program in a Hemodialysis Center.

This article describes the impact of a 12-week workplace wellness program on staff (n = 14) of an outpatient hemodialysis center. The program focused on decreasing dietary sodium and increasing habitual physical activity. The average systolic and diastolic blood pressure of participants decreased by 16.9±21.6 mmHg (p < 0.05) and 4.1±14.0 mmHg (p < 0.05), and body weight decreased by 2.7±1.9kg (p < 0.05). The mean step count at baseline was 7,052±3,278 but increased to 10,388±2,882 (p < 0.05) during a walking challenge. There was a reduction in self-reported barriers to making healthy nutritional changes (p < 0.05) and engaging in habitual physical activity (p < 0.05). Our pilot findings suggest that workplace wellness programs in hemodialysis centers are feasible and effective.

Integrin-associated ILK and PINCH1 protein content are reduced in skeletal muscle of maintenance haemodialysis patients.

KEY POINTS: Patients with renal failure undergoing maintenance haemodialysis are associated with insulin resistance and protein metabolism dysfunction. Novel research suggests that disruption to the transmembrane protein linkage between the cytoskeleton and the extracellular matrix in skeletal muscle may contribute to reduced amino acid metabolism and insulin resistance in haemodialysis. ILK, PINCH1 and pFAKTyr397 were significantly decreased in haemodialysis compared to controls, whereas Rac1 and Akt2 showed no different between groups. Rac1 deletion in the Rac1 knockout model did not alter the expression of integrin-associated proteins. Phenylalanine kinetics were reduced in the haemodialysis group at 30 and 60 min post meal ingestion compared to controls; both groups showed similar levels of insulin sensitivity and ß-cell function. Key proteins in the integrin-cytoskeleton linkage are reduced in haemodialysis patients, suggesting for the first time that integrin-associated proteins dysfunction may contribute to reduced phenylalanine flux without affecting insulin resistance in haemodialysis patients. ABSTRACT: Muscle atrophy, insulin resistance and reduced muscle phosphoinositide 3-kinase-Akt signalling are common characteristics of patients undergoing maintenance haemodialysis (MHD). Disruption to the transmembrane protein linkage between the cytoskeleton and the extracellular matrix in skeletal muscle may contribute to reduced amino acid metabolism and insulin resistance in MHD patients. Eight MHD patients (age: 56 ± 5 years: body mass index: 32 ± 2 kg m-2 ) and non-diseased controls (age: 50 ± 2 years: body mass index: 31 ± 1 kg m-2 ) received primed continuous l-[ring-2 H5 ]phenylalanine before consuming a mixed meal. Phenylalanine metabolism was determined using two-compartment modelling. Muscle biopsies were collected prior to the meal and at 300 min postprandially. In a separate experiment, skeletal muscle tissue from muscle-specific Rac1 knockout (Rac1 mKO) was harvested to investigate whether Rac1 depletion disrupted the cytoskeleton-integrin linkage, allowing for cross-model examination of proteins of interest. ILK, PINCH1 and pFAKTyr397 were significantly lower in MHD (P < 0.01). Rac1 and Akt showed no difference between groups for the human trial. Rac1 deletion in the Rac1 mKO model did not alter the expression of integrin-associated proteins. Phenylalanine rates of appearance and disappearance, as well as metabolic clearance rates, were lower in the MHD group at 30 and 60 min post meal ingestion compared to controls (P < 0.05). Both groups showed similar levels of insulin sensitivity and ß-cell function. Key proteins in the integrin-cytoskeleton linkage are reduced in MHD patients, suggesting for the first time that integrin-associated proteins dysfunction may contribute to reduced phenylalanine flux without affecting insulin resistance in haemodialysis patients.

A Critical Review of Exercise Training in Hemodialysis Patients: Personalized Activity Prescriptions Are Needed.

Exercise training appears to have modest or inconsistent benefits in hemodialysis patients. This may be due to the low volume and intensity of exercise often prescribed. To address this, research is needed to evaluate the efficacy of individualized exercise prescriptions as a component of a comprehensive lifestyle intervention strategy that gives patients more autonomy to choose preferred types of physical activity.

A Comparison of Intradialytic versus Out-of-Clinic Exercise Training Programs for Hemodialysis Patients.

BACKGROUND: Physical inactivity is prevalent and linked with a variety of unfavorable clinical outcomes in hemodialysis patients. To increase physical activity (PA) and improve quality of life in this population, intradialytic and out-of-clinic exercise interventions have been implemented in many studies. However, there is still a lack of consensus in the literature on which type of exercise intervention is more feasible and effective. SUMMARY: This review provides a brief overview of intradialytic and out-of-clinic exercise protocols utilized in previous studies. We also examine data related to the feasibility of each approach, and their efficacy for improving cardiovascular health, muscle mass, strength, and physical function. Key Messages: The benefits from most intradialytic and out-of-center exercise training interventions published to date have been modest or inconsistent. Furthermore, neither appears to provide a significant advantage over the other in terms of benefits for cardiovascular health, muscle mass, strength, and physical function. A significant concern is that most intradialytic and out-of-center exercise interventions are mandated exercise prescriptions that include either endurance or resistance training exercises, performed at low-moderate intensities, for a total of 60-135 min of exercise/week. This volume, intensity, and variety of exercise are far less than what is recommended in most PA guidelines. This type of structured activity is also boring for most patients. To enhance the effectiveness of exercise interventions, we suggest using the intradialytic period to provide patients guidance on how they can best incorporate more activity into their lives, based on their individual needs and barriers.

Managing Hyperkalemia: Another Benefit of Exercise in People With Chronic Kidney Disease?

People with chronic kidney disease (CKD) are at increased risk of hyperkalemia, an electrolyte abnormality that can cause serious, sometimes fatal, cardiac arrhythmias. Muscle contraction causes potassium to be released from cells, increasing serum potassium concentrations. However, these effects are transient, and the long-term impact of exercise training on hyperkalemia risk in CKD patients is largely unknown. In this review, we examine the effects of exercise on factors affecting potassium balance in people with CKD, highlighting the potential benefits of regular exercise on hyperkalemia risk in this population. Although regular exercise is already recommended for people with CKD, research examining this hypothesis may lead to novel therapeutic treatments for this life-threatening condition.

Effect of Oral Nutritional Supplementation With and Without Exercise on Nutritional Status and Physical Function of Adult Hemodialysis Patients: A Parallel Controlled Clinical Trial (AVANTE-HEMO Study).

OBJECTIVE: Protein energy wasting affects the nutritional status (NS) and physical function (PF) of dialysis patients. Among the different anabolic strategies to improve NS and PF, oral nutritional supplementation (ONS) and resistance exercise (RE) or aerobic exercise (AE) have been shown to be effective. Nevertheless, the combination of both anabolic strategies has not been completely evaluated. The aim of this study is to assess the effect of exercise combined with ONS versus ONS without exercise during hemodialysis sessions on PF and NS indicators. METHODS: Young hemodialysis patients (29 ± 9.3 years) with predominantly unknown causes of renal disease (80%) were divided into the following 3 groups during a period of 12 weeks: (1) ONS (n = 15), (2) ONS + RE (n = 15), and (3) ONS + AE (n = 15). Anthropometric, biochemical, PF, and quality of life measurements were recorded at baseline and after 3 months. Repeated measures analysis of variance and effect sizes (Cohen's d) were used to assess the effect of exercise and nutrition (ISRCTN registry 10251828). RESULTS: At the completion of the study, the ONS and ONS + RE groups exhibited statistically significant increases in body weight, body mass index, and in the percentage of fat mass (P < .05); the greatest effect sizes were observed in the ONS + RE group (d = 0.30 for body weight, d = 0.63 for body mass index, and d = 0.90 for the percentage of fat mass). Groups with RE and AE had statistically significant increases and large effect sizes in the six-minute walk test (RE: d = 0.94, P = .02; AE: d = 1.11, P = .03), sit-to-stand test (RE: d = 0.81, P = .041; AE: d = 1.20, P = .002), timed up and go test (RE: d = 1.04, P = .036; AE: d = 1.6, P = .000), and muscle strength (RE: d = 1.01, P = .000; AE: d = 0.60, P = .003). Regarding quality of life, the ONS + RE group had more areas of improvement at the end of the study, followed by the ONS + AE group. No statistically significant differences were found in the repeated measures ANOVA. CONCLUSIONS: The combination of exercise with ONS had larger effects on PF than on ONS alone. Further studies to examine the impact of exercise on the effect of oral nutritional supplementation in dialysis patients are indicated.

Reply to Comments: Comparison of Methods Study between a Photonic Crystal Biosensor and Certified ELISA to Measure Biomarkers of Iron Deficiency in Chronic Kidney Disease Patients.

In this brief note, we respond to the comments made by Dr [...].

Results from the randomized controlled IHOPE trial suggest no effects of oral protein supplementation and exercise training on physical function in hemodialysis patients.

Few long-term studies have assessed whether changes in both diet and exercise can improve the health and quality of life (QOL) of hemodialysis (HD) patients. Here we examined whether 12 months of intradialytic protein supplementation and endurance exercise improves physical function, risk of cardiovascular disease (CVD), and QOL in HD patients in a randomized controlled trial (RCT). A total of 138 HD patients (average age 58 years) were assigned for 12 months to control, intradialytic protein, or protein plus exercise groups. The protein and protein plus exercise groups consumed an oral protein supplement (30 grams of whey) three days/week during dialysis. The protein plus exercise group cycled for 30-45 minutes during dialysis treatment. The primary outcome was change in physical function at 12 months, assessed by a shuttle walk test. Secondary outcomes included arterial stiffness, blood pressure, body composition, muscle strength, markers of nutritional status, and QOL. Assessments were conducted at baseline, 6 and 12 months. In total, 101 patients completed the intervention. There were no significant differences between groups in shuttle walk test performance from baseline to 12 months. There were trends for improvements in some secondary measures of physical function and strength in the protein and protein plus exercise groups at six or 12 months, but these did not reach statistical significance. Thus, our trial did not demonstrate significant improvements in markers of physical function, risk of CVD or QOL after one year of intradialytic oral OPS and aerobic exercise training. More comprehensive lifestyle management may be needed to uncover robust improvements in the health and QOL of HD patients.