Multinutrient Oral Supplements and Tube Feeding in Maintenance Dialysis: A Systematic Review and Meta-Analysis

Effects of oral nutritional supplements on the nutritional status and inflammatory markers in patients on maintenance dialysis: a systematic review and meta-analysis of randomized clinical trials

Background and aims

Patients on hemodialysis (HD) or peritoneal dialysis (PD) often have insufficient energy and protein intake, resulting in poor nutritional status and adverse outcomes. Oral nutritional supplements (ONSs) are the most commonly used to increase such patients' energy and protein intakes.

Methods

In this systematic review and meta-analysis, we analyzed studies on nutritional status, inflammatory markers, and electrolyte levels in patients on dialysis receiving ONSs. We searched four electronic databases from inception until 31 December 2022, for randomized controlled trials comparing ONS treatment versus placebo or routine care.

Results

22 studies with 1185 patients on dialysis were included in our meta-analysis. Compared with the control group, the ONS group exhibited significantly increased serum albumin levels [1.26 g/l (95%CI, 0.50-2.02, P < 0.0001; I2 = 80.4%)], body mass indexes (BMIs) [0.30 kg/m2 (95%CI, 0.09-0.52, P = 0.005; I2 = 41.4%)], and handgrip strength (HGS) [0.96 kg (95%CI, 0.07-1.84, P = 0.034; I2 = 41.4%)] from baseline to the end of intervention. No significant differences were observed between the groups in lean body mass, phase angle, C-reactive protein, and serum phosphorus and potassium levels. In terms of improving albumin, the subgroup analyses show that ONS use seems to be more inclined to three variations: HD patients, short-term use, and non-intradialytic supplementation.

Conclusion

In conclusion, ONS use can improve the nutritional status of patients on dialysis in terms of their serum albumin, BMI, and HGS without significant effects on serum phosphorus, potassium, and C-reactive protein levels. However, it remains uncertain whether these results translate to improvement in clinically relevant outcomes. Large-scale high-quality studies are still required in this population.

Effect on nutritional status and biomarkers of inflammation and oxidation of an oral nutritional supplement (with or without probiotics) in malnourished hemodialysis patients. A multicenter randomized clinical trial "Renacare Trial"

Background

Malnutrition in patients undergoing hemodialysis is frequent and associated with a reduction in muscular mass and strength, with an increment in biomarkers of inflammation and oxidation.

Materials and methods

Randomized, multicenter, parallel-group trial in malnourished hemodialysis patients with three groups [(1) control (C) individualized diet, (2) oral nutritional supplement-ONS- + placebo-SU- PL-, and (3) ONS + probiotics-SU-PR]; the trial was open regarding the intake of ONS or individualized diet recommendations, but double-blind for the intake of probiotics. We obtained, at baseline and after 3 and 6 months, anthropometric measurements, handgrip strength, bioelectrical impedance analysis (BIA), dietary records, and routine biochemical parameters. Inflammation and oxidation were determined using ELISA techniques (Versamax and ProcartaPlex multiplex Immunoassay). Results were analyzed by intention to treat.

Results

A total of 31 patients (11 corresponding to group C, 10 to SU-PL, and 10 to SU-PR) completed the 6-months trial. The two groups that took supplements significantly increased their protein calorie, fat (total and n-3), and fiber intake. Weight and fat-free mass (FFM) also increased significantly in the groups on supplements, both at 3 and 6 months, and dynamometry did so in the SU-PL group. At month 3, prealbumin and vitamin D were significantly increased in the SU-TOT (SU-PL + SU-PR) group. No changes were observed regarding levels of phosphorus and potassium in any of the groups. Urea increased significantly at 6 months in the SU-PL group. There were significant changes in some inflammation biomarkers in the groups on supplements during the intervention (brain-derived neurotrophic factor, bone morphogenetic protein-2, MCP-1, IL-1-beta, IL-10, IL-4, and IL-8). The total antioxidant capacity (TAC) increased significantly in the supplemented patients, with no significant changes observed in isoprostanes.

Conclusion

The specific ONS improved protein-calorie intake, nutritional status (mainly FFM), and some biomarkers of inflammation/oxidation. The addition of probiotics could have a synergistic effect with ONS in such biomarkers.

Clinical trail registration

https://clinicaltrials.gov/ct2/show/, identifier NCT03924089.

Assessing Global Kidney Nutrition Care

BACKGROUND AND OBJECTIVES

Nutrition intervention is an essential component of kidney disease management. This study aimed to understand current global availability and capacity of kidney nutrition care services, interdisciplinary communication, and availability of oral nutrition supplements.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The International Society of Renal Nutrition and Metabolism (ISRNM), working in partnership with the International Society of Nephrology (ISN) Global Kidney Health Atlas Committee, developed this Global Kidney Nutrition Care Atlas. An electronic survey was administered among key kidney care stakeholders through 182 ISN-affiliated countries between July and September 2018.

RESULTS

Overall, 160 of 182 countries (88%) responded, of which 155 countries (97%) answered the survey items related to kidney nutrition care. Only 48% of the 155 countries have dietitians/renal dietitians to provide this specialized service. Dietary counseling, provided by a person trained in nutrition, was generally not available in 65% of low-/lower middle-income countries and "never" available in 23% of low-income countries. Forty-one percent of the countries did not provide formal assessment of nutrition status for kidney nutrition care. The availability of oral nutrition supplements varied globally and, mostly, were not freely available in low-/lower middle-income countries for both inpatient and outpatient settings. Dietitians and nephrologists only communicated "sometimes" on kidney nutrition care in ≥60% of countries globally.

CONCLUSIONS

This survey reveals significant gaps in global kidney nutrition care service capacity, availability, cost coverage, and deficiencies in interdisciplinary communication on kidney nutrition care delivery, especially in lower-income countries.

A Low-Protein Diet with a Renal-Specific Oral Nutrition Supplement Helps Maintain Nutritional Status in Patients with Advanced Chronic Kidney Disease

A low-protein diet (LPD) is recommended to patients with non-dialysis advanced chronic kidney disease (CKD) for delaying renal function decline. However, this approach potentially prevents an adequate calorie and micronutrient intake. We examined the influence of an LPD including a renal-specific oral nutrition supplement (RONS) on the nutrition status of patients with stage 3b–5 CKD. This multicenter, open-label study prospectively enrolled patients over 18 years of age, with an estimated glomerular filtration rate (eGFR) between 10 and 45 mL/min/1.73 m², serum albumin ≥3.0 g/dL, and body mass index ≤30 kg/m². All participants implemented the LPD with one serving of RONS daily for 6 months. Daily energy intake, nutrition status, renal function, and quality of life were assessed before and after the intervention. Of 53 enrolled patients, 35 (66.0%) completed the study. We found that RONS use increased patients’ energy intake and maintained their serum albumin, nutritional status, and quality of life. Body weight and handgrip strength increased significantly at 6 months after enrollment (p = 0.0357); eGFR slightly decreased at 3 and 6 months after enrollment, suggesting that patients’ residual renal function was preserved. Our findings support the conclusion that patients with non-dialysis advanced CKD may benefit from additional RONS besides their regular diet. Patients with advanced CKD receiving RONS might achieve better nutrition and delay renal function decline.

The Effects of Oral Energy-Dense Supplements on Nutritional Status in Nondiabetic Maintenance Hemodialysis Patients: A Randomized Controlled Trial

BACKGROUND AND OBJECTIVES

Fat-based energy-dense nutritional supplements may offer benefits over protein- or carbohydrate-dense supplements for patients receiving dialysis because of the adverse metabolic consequences of the latter. We conducted a randomized controlled trial to assess the effects of the short-term use of a fat-based nutritional supplement on various measures of nutritional status in patients receiving maintenance hemodialysis who have low dietary energy intake.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We enrolled nondiabetic patients receiving hemodialysis for >3 months who had inadequate dietary energy intake (<30 kcal/kg per day). The participants were randomly assigned in a 1:1 ratio to receive an oral fat-based energy-dense supplement (300 kcal daily) or routine care for 12 weeks (n=120 per group). The primary outcome was the change in phase angle measured by bioelectrical impedance analysis, a marker of cell integrity and body cell mass, from the baseline to week 12. The secondary outcomes were changes in quality of life. Other outcomes included laboratory nutritional indicators and physical examinations.

RESULTS

The average age of the total population was 47 (SD: 12) years, and 55% were men. The median of dialysis vintage was 43.4 (22.5-76.3) months; 240 participants were randomly assigned to the intervention (n=120) or control group (n=120). In total, 228 (95%) participants completed the trial. The change in phase angle did not differ significantly between the intervention and control groups (estimate, 0.0; 95% confidence interval, -0.1 to 0.1 versus estimate, 0.0; 95% confidence interval, -0.1 to 0.1; estimated difference, 0.0; 95% confidence interval -0.2 to 0.2; P=0.99). None of the 19 domains of quality of life differed between the groups. Adverse events were reported in 23 (19%) participants in the control group and 40 (33%) participants in the intervention group.

CONCLUSIONS

In nondiabetic patients on maintenance hemodialysis, short-term administration of fat-based energy-dense nutritional supplement has no clinically significant effect on nutritional status as measured by phase angle.

PODCAST

This article contains a podcast at https://https://www.asn-online.org/media/podcast/CJASN/2021_08_03_CJN16821020.mp3.

ESPEN guideline on clinical nutrition in hospitalized patients with acute or chronic kidney disease

Acute kidney disease (AKD) - which includes acute kidney injury (AKI) - and chronic kidney disease (CKD) are highly prevalent among hospitalized patients, including those in nephrology and medicine wards, surgical wards, and intensive care units (ICU), and they have important metabolic and nutritional consequences. Moreover, in case kidney replacement therapy (KRT) is started, whatever is the modality used, the possible impact on nutritional profiles, substrate balance, and nutritional treatment processes cannot be neglected. The present guideline is aimed at providing evidence-based recommendations for clinical nutrition in hospitalized patients with AKD and CKD. Due to the significant heterogeneity of this patient population as well as the paucity of high-quality evidence data, the present guideline is to be intended as a basic framework of both evidence and - in most cases - expert opinions, aggregated in a structured consensus process, in order to update the two previous ESPEN Guidelines on Enteral (2006) and Parenteral (2009) Nutrition in Adult Renal Failure. Nutritional care for patients with stable CKD (i.e., controlled protein content diets/low protein diets with or without amino acid/ketoanalogue integration in outpatients up to CKD stages four and five), nutrition in kidney transplantation, and pediatric kidney disease will not be addressed in the present guideline.

Effectiveness of renal-specific oral nutritional supplements compared with diet counseling in malnourished hemodialysis patients

BACKGROUND

Malnutrition is highly prevalent and a consequence of inflammation and related comorbidities among patients on maintenance hemodialysis. Oral nutritional supplementation (ONS) is recommended for malnourished patients with kidney failure. The study aimed to evaluate renal-specific oral nutrition (ONCE dialyze) supplement on nutritional status in patients on hemodialysis.

METHODS

Patients were randomized into 3 groups; treatment groups received 370 kcal/day of ONCE Dialyze (N = 26) or 370 kcal/day of NEPRO (N = 30) for 30 days. The control group (N = 24) received no intervention. All patients were counseled by the same registered dietitian during the study. The nutritional status was evaluated using malnutrition inflammation score (MIS) assessment, body compositions, serum albumin and pre-albumin levels at baseline and 30 days.

RESULTS

Eighty patients were analyzed with mean age of 57.2 ± 15.9 years. The intervention group exhibited significant improvements in energy, protein, fat, fiber and magnesium intake by dietary interview compared with the control group. Percentage of changes in MIS was - 29.0% (95% CI - 40.5 to - 17.4), - 23.9% (95% CI - 37.2 to - 10.6) and 12.1% (95% CI - 19.2 to 43.4) for the ONCE dialyze, NEPRO and control groups, respectively (overall P = 0.006). Percentage of changes in serum albumin was 5.3% (95% CI 1.9-8.7), 3.3% (95% CI - 0.1 to 6.7) and - 0.8% (95% CI - 4.3 to 2.7) for the ONCE dialyze, NEPRO, and control groups, respectively (overall P = 0.039; P = 0.043 for ONCE dialyze vs. control). No serious adverse effects were reported in any group.

CONCLUSION

Dietary advice combined with ONS especially ONCE dialyze was associated with improved MIS, serum albumin, dietary energy and macronutrient intake among patients with kidney failure on maintenance hemodialysis.

CLINICAL TRIAL REGISTRATION

TCTR20200801001.

Dietary Assessment of Korean Non-dialysis Chronic Kidney Disease Patients with or without Diabetes

BACKGROUND

Dietary intervention at the early stage of chronic kidney disease (CKD) is important for preventing progression to the end-stage renal disease (ESRD). However, few studies have investigated dietary intake of CKD patients in non-dialysis stage. Therefore, we investigated the dietary intake of Korean non-dialysis CKD patients and aimed to establish baseline data for the development of dietary education and intervention strategies for CKD patients.

METHODS

Three hundred fifty CKD patients who visited Seoul National University Hospital outpatient clinic from February 2016 to January 2017 were recruited for this cross-sectional study. Subjects on dialysis and those who had undergone kidney transplantation were excluded. Dietary intake, demographic information, and biochemical characteristics of 256 subjects who completed three-day dietary records were analyzed. Subjects were divided into four groups based on diabetes mellitus (DM) (DM-CKD and Non-DM-CKD groups) and kidney function (Early-CKD and Late-CKD groups).

RESULTS

Total energy intake was lower in the Late-CKD group compared with the Early-CKD group. In men, carbohydrate intake was higher and protein and fat intakes tended to be lower in the Late-CKD group compared with the Early-CKD group. In women, carbohydrate intake tended to be lower in the DM-CKD group than the Non-DM-CKD group. Protein intake tended to be higher in the DM-CKD groups. Phosphorus and sodium intakes were higher in the DM-CKD groups compared with the Non-DM-CKD groups in women, and tended to be higher in the DM-CKD groups in men.

CONCLUSION

DM and kidney function affected energy and nutrient intakes. Subjects in the Late-CKD group consumed less energy than those in the Early-CKD group. Non-DM subjects seemed to restrict protein intake starting from the Early-CKD stage than subjects with DM. Subjects in this study had low energy and high sodium intakes compared with recommended levels. Protein intake was lower in advanced CKD patients, but their intake level was still higher than the recommendation. Dietary intervention strategies for non-dialysis CKD patients need to be customized depending on the presence of DM and kidney function.

Oral protein-based supplements versus placebo or no treatment for people with chronic kidney disease requiring dialysis

BACKGROUND

Malnutrition is common in patients with chronic kidney disease (CKD) on dialysis. Oral protein-based nutritional supplements are often provided to patients whose oral intake is otherwise insufficient to meet their energy and protein needs. Evidence for the effectiveness of oral protein-based nutritional supplements in this population is limited.

OBJECTIVES

The aims of this review were to determine the benefits and harms of using oral protein-based nutritional supplements to improve the nutritional state of patients with CKD requiring dialysis.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 12 December 2019 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of patients with CKD requiring dialysis that compared oral protein-based nutritional supplements to no oral protein-based nutritional supplements or placebo.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed studies for eligibility, risk of bias, and extracted data from individual studies. Summary estimates of effect were obtained using a random-effects model, and results were expressed as risk ratios and their 95% confidence intervals (CI) for dichotomous outcomes, and mean difference and 95% CI for continuous outcomes.

MAIN RESULTS

Twenty-two studies (1278 participants) were included in this review. All participants were adults on maintenance dialysis of whom 79% were on haemodialysis (HD) and 21% peritoneal dialysis. The follow-up period ranged from one to 12 months. The majority of studies were at unclear risk of selection, performance, and reporting bias. The detection bias was high for self-reported outcomes. Oral protein-based nutritional supplements probably lead to a higher mean change in serum albumin compared to the control group (16 studies, 790 participants: MD 0.19 g/dL, 95% CI 0.05 to 0.33; moderate certainty evidence), although there was considerable heterogeneity in the combined analysis (I² = 84%). The increase was more evident in HD participants (10 studies, 526 participants: MD 0.28 g/dL, 95% CI 0.11 to 0.46; P = 0.001 for overall effect) and malnourished participants (8 studies, 405 participants: MD 0.31 g/dL, 95% CI 0.10 to 0.52, P = 0.003 for overall effect). Oral protein-based nutritional supplements also probably leads to a higher mean serum albumin at the end of the intervention (14 studies, 715 participants: MD 0.14 g/dL, 95% CI 0 to 0.27; moderate certainty evidence), however heterogeneity was again high (I² = 80%). Again the increase was more evident in HD participants (9 studies, 498 participants: MD 0.21 g/dL, 95% CI 0.03 to 0.38; P = 0.02 for overall effect) and malnourished participants (7 studies, 377 participants: MD 0.25 g/dL, 95% CI 0.02 to 0.47; P = 0.03 for overall effect). Compared to placebo or no supplement, low certainty evidence showed oral protein-based nutritional supplements may result in a higher serum prealbumin (4 studies, 225 participants: MD 2.81 mg/dL, 95% CI 2.19 to 3.43), and mid-arm muscle circumference (4 studies, 216 participants: MD 1.33 cm, 95% CI 0.24 to 2.43) at the end of the intervention. Compared to placebo or no supplement, oral protein-based nutritional supplements may make little or no difference to weight (8 studies, 365 participants: MD 2.83 kg, 95% CI -0.43 to 6.09; low certainty evidence), body mass index (9 studies, 368 participants: MD -0.04 kg/m², 95% CI -0.74 to 0.66; moderate certainty evidence) and lean mass (5 studies, 189 participants: MD 1.27 kg, 95% CI -1.61 to 4.51; low certainty evidence). Due to very low quality of evidence, it is uncertain whether oral protein-based nutritional supplements affect triceps skinfold thickness, mid-arm circumference, C-reactive protein, Interleukin 6, serum potassium, or serum phosphate. There may be little or no difference in the risk of developing gastrointestinal intolerance between participants who received oral protein-based nutritional supplements compared with placebo or no supplement (6 studies, 426 participants: RR 2.81, 95% CI 0.58 to 13.65, low certainty evidence). It was not possible to draw conclusions about cost or quality of life, and deaths were not reported as a study outcome in any of the included studies.

AUTHORS' CONCLUSIONS

Overall, it is likely that oral protein-based nutritional supplements increase both mean change in serum albumin and serum albumin at end of intervention and may improve serum prealbumin and mid-arm muscle circumference. The improvement in serum albumin was more evident in haemodialysis and malnourished participants. However, it remains uncertain whether these results translate to improvement in nutritional status and clinically relevant outcomes such as death. Large well-designed RCTs in this population are required.

Classifying Enteral Nutrition: Tailored for Clinical Practice

PURPOSE OF REVIEW

To discuss the different forms of enteral nutrition, while outlining available evidence for its use in specific conditions and how enteral nutrition composition may or may not influence relevant outcomes.

RECENT FINDINGS

Enteral nutrition formulas were originally conceived as a liquid form of nutrition for individuals who otherwise could not consume adequate calories through solid food. Over time, the emergence of specialty formulas marketed to benefit specific diseases or conditions has led to a broad range of potentially confusing options. While most options have theoretical benefit for their marketed conditions, the evidence demonstrating practical benefit is not consistent. Overall, the certainty of evidence for specialty formulas remains low or very low. In most instances, one could begin with standard polymeric formula, except in cases where disease-specific formulas are recommended. Much research is nonetheless still needed to clarify whether some disease-specific formulas are truly beneficial or merely theoretical features.

Cachexia/Protein energy wasting syndrome in CKD: Causation and treatment

Cachexia is a multifactorial syndrome defined by significant body weight loss, fat and muscle mass reduction, and increased protein catabolism. Protein energy wasting (PEW) is characterized as a syndrome of adverse changes in nutrition and body composition being highly prevalent in patients with CKD, especially in those undergoing dialysis, and it is associated with high morbidity and mortality in this population. Multiple mechanisms are involved in the genesis of these adverse nutritional changes in CKD patients. There is no obvious distinction between PEW and cachexia from a pathophysiologic standpoint and should be considered as part of the spectrum of the same nutritional disorder in CKD with similar management approaches for prevention and treatment based on current understanding. A plethora of factors can affect the nutritional status of CKD patients requiring a combination of therapeutic approaches to prevent or reverse protein and energy depletion. At present, there is no effective pharmacologic intervention that prevents or attenuates muscle atrophy in catabolic conditions like CKD. Prevention and treatment of uremic muscle wasting involve optimal nutritional support, correction of acidosis, and physical exercise. There has been emerging consistent evidence that active treatment, perhaps by combining nutritional interventions and resistance exercise, may be able to improve but not totally reverse or prevent the supervening muscle wasting and weakness. Active research into more direct pharmacological treatment based on basic mechanistic research is much needed for this unmet medical need in patients with CKD.

The effects of oral nutritional supplements in patients with maintenance dialysis therapy: A systematic review and meta-analysis of randomized clinical trials

Background/objective

This systematic review aims to determine the potential effects of oral nutritional supplements (ONS) in patients receiving maintenance dialysis therapy (MDT).

Methods

Electronic databases were searched without language limits through to July 2018. Randomized controlled trials (RCTs) that involved comparisons of ONS versus placebo or routine care are included in this meta-analysis. RevMan 5.3 statistical software was used for meta-analysis.

Results

15 articles with 589 subjects were included in our study. There are insufficient comparable data of randomized trials to allow meta-analysis of mortality. Albumin levels may be improved by the macronutrient blends or protein/amino acid supplements in MDT patients. Compared with the control group, serum albumin levels and BMI in the ONS group were increased by 1.58 g/L (95% CI, 0.52–2.63, P = 0.003; I² = 85%) and 0.40 kg/m² (95% CI, 0.10–0.71, P = 0.01; I² = 49%), respectively. In the subgroup analysis of patients receiving hemodialysis, albumin levels in ONS group were increased by 2.17 g/L (95% CI, 0.89–3.45, P<0.001; I² = 90%). ONS may not influence serum phosphorus and potassium levels.

Conclusions

Very low-quality evidence suggests that Short-term oral energy or protein/amino acid supplements may improve nutritional status by increasing serum albumin levels and BMI in MDT patients, without influence on serum potassium levels. High-quality and large RCTs, particularly regarding the effects of ONS on mortality and quality of life, are needed to further validate our findings.

Sex Differences in Muscle Wasting

With aging and other muscle wasting diseases, men and women undergo similar pathological changes in skeletal muscle: increased inflammation, enhanced oxidative stress, mitochondrial dysfunction, satellite cell senescence, elevated apoptosis and proteasome activity, and suppressed protein synthesis and myocyte regeneration. Decreased food intake and physical activity also indirectly contribute to muscle wasting. Sex hormones also play important roles in maintaining skeletal muscle homeostasis. Testosterone is a potent anabolic factor promoting muscle protein synthesis and muscular regeneration. Estrogens have a protective effect on skeletal muscle by attenuating inflammation; however, the mechanisms of estrogen action in skeletal muscle are less well characterized than those of testosterone. Age- and/or disease-induced alterations in sex hormones are major contributors to muscle wasting. Hence, men and women may respond differently to catabolic conditions because of their hormonal profiles. Here we review the similarities and differences between men and women with common wasting conditions including sarcopenia and cachexia due to cancer, end-stage renal disease/chronic kidney disease, liver disease, chronic heart failure, and chronic obstructive pulmonary disease based on the literature in clinical studies. In addition, the responses in men and women to the commonly used therapeutic agents and their efficacy to improve muscle mass and function are also reviewed.

Malnutrition in Dialysis Patients--The Need for Intervention Despite Uncertain Benefits

We are in the midst of an epidemic of overnutrition which has resulted in a widespread increase in obesity rates in modern societies. Yet for patients suffering from serious chronic illnesses such as end stage renal disease (ESRD), malnutrition (encompassing both inadequate quantity and quality of nutrient intake) represents a far more significant danger. Protein-energy wasting has been identified as one of the strongest risk factor for adverse outcomes in ESRD patients, and modeling studies have suggested that improving nutrition could result in substantial lowering of mortality rates and other benefits. To date there is ample evidence that various interventions can have a positive impact on the nutritional status of ESRD patients, yet we still lack randomized controlled clinical trials showing that the same interventions could indeed lead to better survival or other clinical benefits. This knowledge gap, which is all too common for clinical problems encountered in nephrology, should not act as a deterrent, but it should rather incentivize us to continue exploring novel interventions aimed at improving malnutrition in ESRD.

Muscle wasting in end-stage renal disease promulgates premature death: established, emerging and potential novel treatment strategies

Muscle wasting (or sarcopenia) is a common feature of the uremic phenotype and predisposes this vulnerable patient population to increased risk of comorbid complications, poor quality of life, frailty and premature death. The old age of dialysis patients is in addition a likely contributor to loss of muscle mass. As recent evidence suggests that assessment of muscle strength (i.e. function) is a better predictor of outcome and comorbidities than muscle mass, this opens new screening, assessment and therapeutic opportunities. Among established treatment strategies, the benefit of resistance exercise and endurance training are increasingly recognized among nephrologists as being effective and should be promoted in sedentary chronic kidney disease patients. Testosterone and growth hormone replacement appear as the most promising among emerging treatments strategies for muscle wasting. As treatment of muscle wasting is difficult and seldom successful in this often old, frail, sedentary and exercise-hesitant patient group, novel treatment strategies are urgently needed. In this review, we summarize recent studies on stimulation of mitochondrial biogenesis, myogenic stem (satellite) cells and manipulation of transforming growth factor family members, all of which hold promise for more effective therapies to target muscle mass loss and function in the future.

NOURISH, Nutritional OUtcomes from a Randomised Investigation of Intradialytic oral nutritional Supplements in patients receiving Haemodialysis: a pilot randomised controlled trial

Background

The study was done to assess the feasibility of conducting a trial evaluating the use of an intradialytic oral nutritional supplement (ONS) on nutritional status.

Methods

The study design is a single centre, parallel group, external pilot randomised controlled trial (RCT). The setting was at a haemodialysis unit in Sheffield, UK. The aim was to recruit 30 trial participants to allow at least 12 evaluable patients per arm, but the actual study sample consisted of 10 adults with a body mass index (BMI) ≤22 kg/m², receiving thrice weekly haemodialysis. All participants received nutritional advice from a renal dietitian as per usual practice. The intervention included the provision of an intradialytic ONS. Feasibility outcomes included recruitment to time and retention of participants along with palatability of ONS. Secondary outcomes were clinical parameters to obtain variance and estimates of effect size to inform the sample size calculation for a definitive trial.

Results

Recruitment was undertaken for a fixed period of 6 weeks. Rates were lower than expected mainly due to ineligibility with only 7% of screened patients (19/265) being eligible and 4% (10/265) of these being recruited. Due to the small proportion of patients eligible for the trial, all haemodialysis patients at the specified unit were assessed for eligibility. Data completion rates were low for session questionnaires (23%). Sample sizes derived from variance in secondary outcome measure of handgrip strength and adjusted for a dropout rate of 20% indicate that 189 patients would be required for a definitive RCT, requiring 19 UK haemodialysis units to participate.

Conclusions

A definitive RCT is feasible with some adaptation to exclusion criteria and methodology. The exclusion criteria could be adapted to include an increase in upper limit for BMI. The use of questionnaires at each dialysis session may not be feasible but the inclusion of appetite and supplement consumption data collection at the main assessments would provide similar outcome data. Quality of life assessment using SF-12 would be acceptable.

Trial registration

ISRCTN37431579.

Enteral nutrition formula selection: current evidence and implications for practice

Many new enteral nutrition (EN) formulas have been created over the past several decades with a variety of intended uses. Although each is intended to promote improved outcomes, research is often unclear and, in many cases, conflicting. It is important to note that EN products are considered medical foods by the U.S. Food and Drug Administration and therefore do not have to complete premarket review or approval and are not regulated to the same extent as pharmaceuticals. While standard EN formulas are designed to meet the basic macro- and micronutrient requirements of individuals who cannot meet nutrition needs orally, specialty EN products have been developed to exhibit pharmacologic properties, such as immune-enhancing formulas containing arginine, glutamine, nucleotides, and ω-3 fatty acids. With the vast number of products available, rising costs of healthcare, and the drive toward evidence-based practice, it is imperative that clinicians carefully consider research regarding use of specialty formulas, paying close attention to the quality, patient population, clinical end points, and cost to patient and/or facility.

Nutrition prescription to achieve positive outcomes in chronic kidney disease: a systematic review

In Chronic Kidney Disease (CKD), management of diet is important in prevention of disease progression and symptom management, however evidence on nutrition prescription is limited. Recent international CKD guidelines and literature was reviewed to address the following question “What is the appropriate nutrition prescription to achieve positive outcomes in adult patients with chronic kidney disease?” Databases included in the search were Medline and CINAHL using EBSCOhost search engine, Embase and the Cochrane Database of Systematic Reviews published from 2000 to 2009. International guidelines pertaining to nutrition prescription in CKD were also reviewed from 2000 to 2013. Three hundred and eleven papers and eight guidelines were reviewed by three reviewers. Evidence was graded as per the National Health and Medical Research Council of Australia criteria. The evidence from thirty six papers was tabulated under the following headings: protein, weight loss, enteral support, vitamin D, sodium, fat, fibre, oral nutrition supplements, nutrition counselling, including protein and phosphate, nutrients in peritoneal dialysis solution and intradialytic parenteral nutrition, and was compared to international guidelines. While more evidence based studies are warranted, the customary nutrition prescription remains satisfactory with the exception of Vitamin D and phosphate. In these two areas, additional research is urgently needed given the potential of adverse outcomes for the CKD patient.

Muscle wasting in hemodialysis patients: new therapeutic strategies for resolving an old problem

Muscle wasting has long been recognized as a major clinical problem in hemodialysis (HD) patients. In addition to its impact on quality of life, muscle wasting has been proven to be associated with increased mortality rates. Identification of the molecular mechanisms underlying muscle wasting in HD patients provides opportunities to resolve this clinical problem. Several signaling pathways and humeral factors have been reported to be involved in the pathogenic mechanisms of muscle wasting in HD patients, including ubiquitin-proteasome system, caspase-3, insulin/insulin-like growth factor-1 (IGF-1) signaling, endogenous glucocorticoids, metabolic acidosis, inflammation, and sex hormones. Targeting the aforementioned crucial signaling and molecules to suppress protein degradation and augment muscle strength has been extensively investigated in HD patients. In addition to exercise training, administration of megestrol acetate has been proven to be effective in improving anorexia and muscle wasting in HD patients. Correction of metabolic acidosis through sodium bicarbonate supplements can decrease muscle protein degradation and hormone therapy with nandrolone decanoate has been reported to increase muscle mass. Although thiazolidinedione has been shown to improve insulin sensitivity, its role in the treatment of muscle wasting remains unclear. This review paper focuses on the molecular pathways and potential new therapeutic approaches to muscle wasting in HD patients.

Anti-Inflammatory and Anti-Oxidative Nutrition in Hypoalbuminemic Dialysis Patients (AIONID) study: results of the pilot-feasibility, double-blind, randomized, placebo-controlled trial

BACKGROUND

Low serum albumin is common and associated with protein-energy wasting, inflammation, and poor outcomes in maintenance hemodialysis (MHD) patients. We hypothesized that in-center (in dialysis clinic) provision of high-protein oral nutrition supplements (ONS) tailored for MHD patients combined with anti-oxidants and anti-inflammatory ingredients with or without an anti-inflammatory appetite stimulator (pentoxifylline, PTX) is well tolerated and can improve serum albumin concentration.

METHODS

Between January 2008 and June 2010, 84 adult hypoalbuminemic (albumin <4.0 g/dL) MHD outpatients were double-blindly randomized to receive 16 weeks of interventions including ONS, PTX, ONS with PTX, or placebos. Nutritional and inflammatory markers were compared between the four groups.

RESULTS

Out of 84 subjects (mean ± SD; age, 59 ± 12 years; vintage, 34 ± 34 months), 32 % were Blacks, 54 % females, and 68 % diabetics. ONS, PTX, ONS plus PTX, and placebo were associated with an average change in serum albumin of +0.21 (P = 0.004), +0.14 (P = 0.008), +0.18 (P = 0.001), and +0.03 g/dL (P = 0.59), respectively. No related serious adverse events were observed. In a predetermined intention-to-treat regression analysis modeling post-trial serum albumin as a function of pre-trial albumin and the three different interventions (ref = placebo), only ONS without PTX was associated with a significant albumin rise (+0.17 ± 0.07 g/dL, P = 0.018).

CONCLUSIONS

In this pilot-feasibility, 2 × 2 factorial, placebo-controlled trial, daily intake of a CKD-specific high-protein ONS with anti-inflammatory and anti-oxidative ingredients for up to 16 weeks was well tolerated and associated with slight but significant increase in serum albumin levels. Larger long-term controlled trials to examine hard outcomes are indicated.

Nutritional outcomes from a randomised investigation of intradialytic oral nutritional supplements in patients receiving haemodialysis, (NOURISH): a protocol for a pilot randomised controlled trial

Abstract

Haemodialysis is a form of renal replacement therapy but is a catabolic process that not only filters toxins but is also known to lead to amino acid losses. Patients with chronic kidney disease often have a poor appetite and this in combination with limited dietary intake and the detrimental effects of haemodialysis can lead to the development of malnutrition. Between 20% and 50% of haemodialysis patients are thought to be malnourished. Malnutrition can worsen clinical outcomes and increase the risk of hospitalisation. We hypothesise that a nutritional supplement taken during haemodialysis may help to improve nutritional status.

The aim of this study is to conduct a pilot randomised controlled trial to assess the use of an intradialytic nutritional supplement on nutritional status. The objectives are to assess the feasibility of the trial including: recruitment and retention of participants; preference of nutritional supplements; compliance with the intervention; ease of completion of the questionnaires and appropriateness of the tools used. Secondary outcomes include clinical outcomes to obtain variance in the patient population and estimates of effect size to inform the sample size for a future definitive trial.

The trial is a single centre, randomised, parallel-group, two armed external pilot with an intervention and control group. The intervention group will take a nutritional supplement each dialysis session from a choice of prescribable drink or pudding style supplements. The control group will receive standard care.

Recruitment and feasibility elements are the primary outcomes. Recruitment will be to time (t = 6 weeks). In order to collect sufficient data to inform a future sample size calculation, we will aim to recruit 30 participants to obtain 12 evaluable per arm anticipating some drop out. Secondary outcome measures include clinical variables; hand grip strength, quality of life, weight and biochemistry completed at baseline, 1 and 2 months.

Descriptive statistics will be used to analyse the baseline characteristics of the recruited participants. Means, confidence intervals and standard deviations will be reported for the outcome measures of handgrip strength, dietary intake, quality of life and weight.

Trial registration

ISRCTN37431579.

Prevention and treatment of protein energy wasting in chronic kidney disease patients: a consensus statement by the International Society of Renal Nutrition and Metabolism

Protein energy wasting (PEW) is common in patients with chronic kidney disease (CKD) and is associated with adverse clinical outcomes, especially in individuals receiving maintenance dialysis therapy. A multitude of factors can affect the nutritional and metabolic status of CKD patients requiring a combination of therapeutic maneuvers to prevent or reverse protein and energy depletion. These include optimizing dietary nutrient intake, appropriate treatment of metabolic disturbances such as metabolic acidosis, systemic inflammation, and hormonal deficiencies, and prescribing optimized dialytic regimens. In patients where oral dietary intake from regular meals cannot maintain adequate nutritional status, nutritional supplementation, administered orally, enterally, or parenterally, is shown to be effective in replenishing protein and energy stores. In clinical practice, the advantages of oral nutritional supplements include proven efficacy, safety, and compliance. Anabolic strategies such as anabolic steroids, growth hormone, and exercise, in combination with nutritional supplementation or alone, have been shown to improve protein stores and represent potential additional approaches for the treatment of PEW. Appetite stimulants, anti-inflammatory interventions, and newer anabolic agents are emerging as novel therapies. While numerous epidemiological data suggest that an improvement in biomarkers of nutritional status is associated with improved survival, there are no large randomized clinical trials that have tested the effectiveness of nutritional interventions on mortality and morbidity.

Optimal nutrition in hemodialysis patients

Protein-energy wasting (PEW) is highly prevalent in patients undergoing maintenance hemodialysis (MHD). It is important to note that there is a robust association between the extent of PEW and the risk of hospitalization and death in these patients, regardless of the nutritional marker used. The multiple etiologies of PEW in advanced kidney disease are still being elucidated. Apart from the multiple mechanisms that might lead to PEW, it appears that the common pathway for all of the derangements is related to exaggerated protein degradation along with decreased protein synthesis. The hemodialysis procedure per se is an important contributor to this process. Metabolic and hormonal derangements such as acidosis, inflammation, and resistance to anabolic properties of insulin resistance and growth hormone are all implicated for the development of PEW in MHD patients. Appropriate management of MHD patients at risk for PEW requires a comprehensive combination of strategies to diminish protein and energy depletion and to institute therapies that will avoid further losses. The mainstay of nutritional treatment in MHD patients is provision of an adequate amount of protein and energy, using oral supplementation as needed. Intradialytic parenteral nutrition should be attempted in patients who cannot efficiently use the gastrointestinal tract. Other anabolic strategies such as exercise, anabolic hormones, anti-inflammatory therapies, and appetite stimulants can be considered as complementary therapies in suitable patients.

Frailty and protein-energy wasting in elderly patients with end stage kidney disease

Older people constitute an increasingly greater proportion of patients with advanced CKD, including those patients undergoing maintenance dialysis treatment. Frailty is a biologic syndrome of decreased reserve and resistance to stressors that results from cumulative declines across multiple physiologic systems and causes vulnerability to adverse outcomes. Frailty is common in elderly CKD patients, and it may be associated with protein-energy wasting (PEW), sarcopenia, dynapenia, and other complications of CKD. Causes of frailty with or without PEW in the elderly with CKD can be classified into three categories: causes primarily caused by aging per se, advanced CKD per se, or a combination of both conditions. Frailty and PEW in elderly CKD patients are associated with impaired physical performance, disability, poorer quality of life, and reduced survival. Prevention and treatment of these conditions in the elderly CKD patients often require a multifaceted approach. Here, we examine the causes and consequences of these conditions and examine the interplay between frailty and PEW in elderly CKD patients.

Association between oral nutritional supplementation and clinical outcomes among patients with ESRD

BACKGROUND AND OBJECTIVES

Oral nutritional supplementation (ONS) was provided to ESRD patients with hypoalbuminemia as part of Fresenius Medical Care Health Plan's (FMCHP) disease management. This study evaluated the association between FMCHP's ONS program and clinical outcomes.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Analyses included FMCHP patients with ONS indication (n=470) defined as 2-month mean albumin <3.8 g/dl until reaching a 3-month mean ≥3.8 g/dl from February 1, 2006 to December 31, 2008. Patients did not receive ONS if deemed inappropriate or refused. Patients on ONS were compared with patients who were not, despite meeting ONS indication. Patients with ONS indication regardless of use were compared with Medicare patients with similar serum albumin levels from the 2007 Centers for Medicare and Medicaid Services Clinical Performance Measures Project (CPM). Cox models calculated adjusted hospitalization and mortality risks at 1 year.

RESULTS

Among patients with indication for ONS, 276 received supplements and 194 did not. ONS use was associated with 0.058 g/dl higher serum albumin overall (P=0.02); this difference decreased by 0.001 g/dl each month (P=0.05) such that the difference was 0.052 g/dl (P=0.04) in month 6 and the difference was no longer significant in month 12 . In analyses based on ONS use, ONS patients had lower hospitalization at 1 year (68.4%; P<0.01) versus patients without ONS (88.7%), but there was no significant reduction in mortality risk (P=0.29). In analyses based on ONS indication, patients with indication had lower mortality at 1 year (16.2%) compared with CPM patients (23.4%; P<0.01).

CONCLUSIONS

These findings suggest that ONS use was associated with significantly lower hospitalization rates but had no significant effect on mortality in a disease management setting.

Outcomes associated with intradialytic oral nutritional supplements in patients undergoing maintenance hemodialysis: a quality improvement report

BACKGROUND

Insufficient clinical data exist to determine whether provision of oral nutritional supplements during dialysis can improve survival in hypoalbuminemic maintenance hemodialysis patients.

STUDY DESIGN

Retrospective matched-cohort study.

SETTING & PARTICIPANTS

All oral nutritional supplement program-eligible in-center maintenance hemodialysis patients with albumin level ≤3.5 g/dL in quarter 4 of 2009 without oral nutritional supplements in the prior 90 days at Fresenius Medical Care, North America facilities.

QUALITY IMPROVEMENT PLAN

Monitored intradialytic oral nutritional supplements were provided to eligible maintenance hemodialysis patients upon physician order, to continue for a year or until serum albumin level was ≥4.0 g/dL.

OUTCOME

Mortality (including deaths and withdrawals), followed up until December 31, 2010.

MEASUREMENTS

Both an intention-to-treat (ITT) and an as-treated analysis was performed using a 1:1 geographic region and propensity score-matched study population (using case-mix, laboratory test, access type, 30-day prior hospitalization, and incident patient status) comparing patients treated with intradialytic oral nutritional supplements with usual-care patients. Cox models were constructed, unadjusted and adjusted for facility standardized mortality ratio and case-mix and laboratory variables.

RESULTS

The ITT and as-treated analyses both showed lower mortality in the oral nutritional supplement group. The conservative ITT models with 5,227 matched pairs had 40% of controls subsequently receiving oral nutritional supplements after January 1, 2010 (because many physicians delayed participation), with comparative death rates of 30.1% versus 30.4%. The corresponding as-treated (excluding crossovers) death rates for 4,289 matched pairs were 30.9% versus 37.3%. The unadjusted ITT mortality HR for oral nutritional supplement use was 0.95 (95% CI, 0.88-1.01), and the adjusted HR was 0.91 (95% CI, 0.85-0.98); the corresponding as-treated HRs were 0.71 (95% CI, 0.66-0.76) and 0.66 (95% CI, 0.61-0.71) before and after adjustment, respectively.

LIMITATIONS

Limited capture of oral nutritional supplement intake outside the facility and potential residual confounding from unmeasured variables, such as dietary intake.

CONCLUSIONS

Maintenance hemodialysis patients with albumin levels ≤3.5 g/dL who received monitored intradialytic oral nutritional supplements showed survival significantly better than similar matched patient controls, with the as-treated analysis highlighting the potentially large effect of this strategy in clinical practice.

Intensity of care and better outcomes among hemodialysis patients: a role for the Medical Director

The Medical Director is responsible for all levels of quality patient care in the facility as mandated by the 2008 revision of the Medicare Conditions for Coverage of dialysis facilities. He/she is the leader and primary individual tasked with ensuring that facility processes are in place to meet or exceed key quality goals or adopt new ones and prioritize them appropriately-all to drive improved facility performance, particularly the ultimate outcomes of morbidity and mortality rates. Management of vascular access, dialysis dose, mineral metabolism, acid-base balance, sodium and fluid management, anemia, among other aspects of care, have representative intermediate clinical outcomes that are often called "surrogate" or "process" measures-because they may reflect the quality of care delivery while impacting "primary" outcomes such as death and hospitalization. The proportion of dialysis patients within a dialysis facility meeting a selected group among these goals has become the standard "care process" metric since the 1990s. Evidence supports its use, in that graded improvements in the facility patients' primary outcomes have been documented as more patients in a facility achieved a greater number of these "process" goals. A caveat: these process measures do not represent overall quality by themselves because nonclinical processes also influence primary outcomes. Nevertheless, process improvement in meeting facility goals should be led by the Medical Director, particularly those with the strongest links to primary outcomes such as reduction of hemodialysis catheter exposure, forming the cornerstone of quality improvement efforts. Specific recommendations on how to effectively lead a care team to achieve these goals are discussed.

Effects of protein and omega-3 supplementation, provided during regular dialysis sessions, on nutritional and inflammatory indices in hemodialysis patients

Purpose

Malnutrition and chronic inflammation in dialysis patients negatively impacts prognosis. However, intervening to correct this problem (through nutritional supplementation) is often hampered by poor compliance due to both medical and socioeconomic barriers. We have therefore performed a pilot study to investigate the technical feasibility of “directly observed treatment” of nutritional supplementation (protein and omega-3 fatty acids), administered during regular dialysis sessions. Secondary end points included observation of nutritional and inflammatory status of hypoalbuminemic patients undergoing hemodialysis.

Methods

Main inclusion criteria were serum albumin ≤ 3.9 g/dL (3 months prior to the study). Sixty-three eligible patients agreed to participate. Two intervention groups received 30 mL of a liquid protein supplement plus either 2.4 g omega-3 (1800 mg eicosapentaenoic acid + 600 mg docosahexaenoic acid) or a placebo, three times per week after their routine dialysis session for 6 months. Serum albumin, plasma lipids, and other indicators of nutritional and inflammatory status were measured.

Results

Directly observed nutritional supplementation resulted in a significant improvement in the low density lipoprotein cholesterol/high density lipoprotein cholesterol ratio in the omega-3 group as compared to the placebo group (P = 0.043). For the omega-3 group, serum albumin was also marginally higher after 6 months as compared to baseline (P = 0.07). The observed increase in C-reactive protein in the placebo group over 6 months was not apparent in the omega-3 group, although there was no significant difference between groups. Nuclear factor kappa B, malnutrition-inflammation score, normalized protein nitrogen appearance, body mass index, and hemoglobin were unaffected by the intervention.

Conclusion

“Directly observed treatment” with an omega-3 based supplement (as opposed to a pure protein supplement) showed beneficial effects on the lipid profile, and C-reactive protein levels. Further studies using a combination of outpatient and inpatient “directly observed treatment” of omega-3 based supplementation is warranted.

Multivariate meta-analysis: a robust approach based on the theory of U-statistic

Meta-analysis is the methodology for combining findings from similar research studies asking the same question. When the question of interest involves multiple outcomes, multivariate meta-analysis is used to synthesize the outcomes simultaneously taking into account the correlation between the outcomes. Likelihood-based approaches, in particular restricted maximum likelihood (REML) method, are commonly utilized in this context. REML assumes a multivariate normal distribution for the random-effects model. This assumption is difficult to verify, especially for meta-analysis with small number of component studies. The use of REML also requires iterative estimation between parameters, needing moderately high computation time, especially when the dimension of outcomes is large. A multivariate method of moments (MMM) is available and is shown to perform equally well to REML. However, there is a lack of information on the performance of these two methods when the true data distribution is far from normality. In this paper, we propose a new nonparametric and non-iterative method for multivariate meta-analysis on the basis of the theory of U-statistic and compare the properties of these three procedures under both normal and skewed data through simulation studies. It is shown that the effect on estimates from REML because of non-normal data distribution is marginal and that the estimates from MMM and U-statistic-based approaches are very similar. Therefore, we conclude that for performing multivariate meta-analysis, the U-statistic estimation procedure is a viable alternative to REML and MMM. Easy implementation of all three methods are illustrated by their application to data from two published meta-analysis from the fields of hip fracture and periodontal disease. We discuss ideas for future research based on U-statistic for testing significance of between-study heterogeneity and for extending the work to meta-regression setting.

[Efficacy of oral supplementation during dialysis in patients with chronic renal failure]

Protein-calorie malnutrition is common in hemodialysis patients and is a powerful predictor of morbidity and mortality. Nutritional supplementation, administered orally or parenterally, especially during dialysis, may compensate for the relatively inadequate protein and energy intake and improves net protein anabolism in chronic hemodialysis patients. Intradialytic oral nutrition seems preferable to intradialytic parenteral nutrition (IDPN) due to its lower cost and persistence of its anabolic effects after infusion is stopped, and because IDPN induces a higher increase in serum glucose and insulin levels and a greater reduction in serum ghrelin concentrations. Further larger scale randomized, controlled trials of nutritional interventions should be performed in maintenance dialysis patients to assess their efficacy regarding quality of life, morbidity, and mortality.

Practical management of diet and lifestyle interventions for people with diabetes or cardiovascular disease

Increased collaboration between the vascular specialities is clearly leading to increased understanding of the interrelationships between the different disease states and how each impacts and influences the other. This advantage will be reflected in improved patient care if the practical outputs of this growing knowledge are carefully implemented at service level. This article outlines how the aspects of diet and lifestyle associated with vascular-related disease complement, contrast and in some cases contradict each other. It gives information and guidelines as to how the expertise of dietitians working in the different specialist areas might usefully be shared to be of maximum advantage to all patients.

The effect of resistance exercise to augment long-term benefits of intradialytic oral nutritional supplementation in chronic hemodialysis patients

BACKGROUND

Resistance exercise combined with intradialytic oral nutrition (IDON) supplementation improves net protein balance in the acute setting in chronic hemodialysis patients. We hypothesized that combination of long-term resistance exercise and IDON would improve markers of muscle mass and strength further compared with IDON alone.

METHODS

Thirty-two participants (21 male; mean age, 43 ± 13 years) on chronic hemodialysis were randomly assigned to IDON plus resistance exercise (NS + EX), or IDON (NS) alone for 6 months. IDON consisted of a lactose-free formula consisting of protein, carbohydrate, and fat. Three sets of 12 repetitions of leg-press were completed before each dialysis session in the NS + EX arm. Primary outcome measurement was lean body mass. Muscle strength and other nutritional parameters were measured as secondary outcomes.

RESULTS

Of 32 participants, 22 completed the 6-month intervention. There were no statistically significant differences between the study interventions with respect to changes in lean body mass and body weight, when comparing NS + EX to NS. There were also no statistically significant differences in any of the secondary outcomes measured in the study. Body weight (80.3 ± 16.6 kg, 81.1 ± 17.5 kg, and 80.9 ± 18.2 kg at baseline, month 3, and month 6, respectively; P = .02) and 1-repetition maximum (468 ± 148 lb, 535 ± 144 lb, and 552 ± 142 lb, respectively; P = .001) increased statistically significantly during the study for all patients combined.

CONCLUSION

This study did not show further benefits of additional resistance exercise on long-term somatic protein accretion above and beyond nutritional supplementation alone. When both treatments groups were combined, body weight and muscle strength improved during the study.