Is There a Role for Intradialytic Parenteral Nutrition? A Review of the Evidence

Research progress on influencing factors and intervention methods of protein-energy wasting in maintenance hemodialysis patients: A literature review

Protein-energy wasting (PEW) has high incidence in hemodialysis patients and refers to a state of decreased protein and energy substance. With the extensive development of hemodialysis in patients with end-stage kidney disease, most patients with maintenance hemodialysis have the problem of PEW, which is one of the common complications of maintenance hemodialysis patients, resulting in decreased quality of life and increased mortality. This article searches and analyzes the literature in recent years to summarize the current influencing factors and common interventions of PEW in maintenance hemodialysis patients, which will provide reference for subsequent nutritional management of maintenance hemodialysis patients.

Managing Zinc Supplementation in Hemodialysis Patients: Balancing and Preventing Deficiencies in Serum Copper and Zinc Levels with and Without HIF-PH Inhibitors

BACKGROUND/OBJECTIVES

Zinc supplementation induces metallothionein, leading to reduced serum copper levels. Conversely, serum copper concentrations tend to rise with the use of HIF-PH inhibitors.

METHODS

To establish a safe level of zinc supplementation that avoids copper deficiency, serum copper and zinc concentrations measured every three months were retrospectively analyzed over five years in 50 patients undergoing hemodialysis.

RESULTS

At the initiation of the study, the median (IQR) concentrations were 100 (84.25-109) µg/dL for serum copper and 60.5 (50.5-70) µg/dL for serum zinc. All participants without zinc supplementation exhibited zinc deficiency (<80 µg/dL). After three months, copper deficiency (<71 µg/dL) was observed when serum copper concentrations were <98.6 µg/dL for patients with HIF-PH inhibitors and <90.3 µg/dL for patients without them. Reduced zinc supplementation may be necessary when serum copper falls below 90 µg/dL. Zinc levels remained deficient because supplementation was limited due to concerns about copper deficiency. Lowering the target zinc level to around 80 µg/dL instead of the conventional 80-120 µg/dL may be safer.

CONCLUSIONS

Regular monitoring of both copper and zinc levels, taking place at least every three months, is recommended to adjust zinc supplementation, especially in patients on HIF-PH inhibitors. Copper supplementation should also be considered alongside zinc supplementation to effectively treat hypozincemia.

Intradialytic Parenteral Nutrition in Patients on Hemodialysis: A Multicenter Retrospective Study

BACKGROUND AND OBJECTIVE

To evaluate the effectiveness and safety of intradialytic parenteral nutrition (IDPN) on different nutritional outcomes.

METHODS

This was a retrospective analysis for a "routinely collected data bank" in a multicenter cohort, conducted on consecutive malnourished or at-risk of malnutrition patients with chronic kidney disease on hemodialysis who underwent IDPN with a three-in-one parenteral nutrition formula for a period ≥ 2 weeks. The primary endpoint was the mean change in the malnutrition inflammation score (MIS) score between baseline and the last follow-up visit on IDPN.

RESULTS

Fifty-six patients were included. The mean age was 72.4 ± 12.0 years, and 24 (42.9%) were women. In the overall study sample, MIS significantly decreased from 16.4 (95%CI: 15.3-17.65) at baseline to 14.3 (95%CI: 12.8-15.8) at the last follow-up visit on IDPN (p = 0.0019). Fifteen (26.8%) patients achieved a MIS reduction ≥ 5 points after IDPN. As compared to baseline, IDPN significantly reduced the proportion of patients with protein-energy wasting (PEW) (89.3% versus 66.1%, respectively, p = 0.0023). Regarding analytical parameters, serum albumin (p = 0.0003) and total proteins (p = 0.0024) significantly increased after IDPN administration. Throughout the study's follow-up period, 45 (80.4%) patients reported experiencing some type of adverse event.

CONCLUSIONS

IDPN was associated with a significant improvement in the nutritional profile. Notably, our research found that the administration of IDPN over a duration > 3 months significantly improved the nutritional status of patients evaluated by the MIS test.

Revisiting Intradialytic Parenteral Nutrition: How Can We Apply the Evidence in Clinical Practice?

Intradialytic parenteral nutrition (IDPN) remains a controversial nutrition support practice in hemodialysis. Multiple reviews and evidence-based clinical practice guidelines have been published in the past 20 years. Despite essentially looking at the same evidence, conclusions and recommendations vary significantly, leading to widespread uncertainty among clinicians on the value of and indications for IDPN. This paper aims to bring a clinical perspective to the current state of evidence and clinical practice, recognizing the strengths and weaknesses of current evidence and the clinical questions that remain unanswered, as well as providing guidance for using IDPN in clinical practice. IDPN should be considered a strategy to complement spontaneous oral intake in clinically stable patients receiving maintenance hemodialysis or who have or are at risk of malnutrition and who have substantial but not adequate protein and/or energy intake. There is a clear need for robust randomized controlled trials evaluating the impact of IDPN in appropriately selected patients. Additionally, future trials should include patient-centered outcome measures such as appetite, spontaneous oral intake, quality of life, and reliable measures of nutritional status.

Intradialytic parenteral nutrition for patients on hemodialysis: when, how and to whom?

Hemodialysis is associated with high morbidity and mortality rates as well as low quality of life. Altered nutritional status and protein-energy wasting are important indicators of these risks. Maintaining optimal nutritional status in patients with hemodialysis is a critical but sometimes overlooked aspect of care. Nutritional support strategies usually begin with dietary counseling and oral nutritional supplements. Patients may not comply with this advice or oral nutritional supplements, however , or compliance may be affected by other complications of progressive chronic kidney disease. Intradialytic parenteral nutrition (IDPN) may be a possibility in these cases, but lack of knowledge on practical aspects of IDPN delivery are seldom discussed and may represent a barrier. In this review, we, as a consensus panel of clinicians experienced with IDPN, survey existing literature and summarize our views on when to use IDPN, which patients may be best suited for IDPN, and how to effectively deliver and monitor this strategy for nutritional support.

The beneficial effects of intradialytic parenteral nutrition in hemodialysis patients with protein energy wasting: a prospective randomized controlled trial

In hemodialysis (HD) patients, protein-energy wasting (PEW) is highly prevalent and firstly treated with oral nutritional supplements (ONS). The extent to which intradialytic parenteral nutrition (IDPN) contributes to improve PEW status in HD patients intolerable to ONS remains unclear. Maintenance PEW HD patients being unable to tolerate ONS adverse effects, and having spontaneous energy and protein intake of ≥ 20 kcal/kg/day and ≥ 0.8 g/kg/day, respectively were randomly assigned 1:1 into IDPN and control groups. In IDPN group, most concentrated 3-in-1, fish-oil based parenteral nutrition was infused during HD for 3 months. The control group received intensive dietary counselling once weekly for 3 months. Both groups were then followed for additional 3 months after intervention. A total of 38 patients were randomized (mean age 67.6 years). After 3 months, serum albumin was significantly higher in the IDPN (n = 18) compared with control group (from 3.5 ± 0.3 to 3.8 ± 0.2 vs from 3.6 ± 0.3 to 3.5 ± 0.3 g/dL, respectively, p = 0.01). Spontaneous dietary intake (p = 0.04), body weight (p = 0.01), and malnutrition inflammation score (MIS, p = 0.01) were improved in the IDPN, but not in the control group. Muscle mass, strength, serum prealbumin, interleukin-6, high sensitivity-c reactive protein, and acylated ghrelin were not significantly different but leptin levels increased in the control group after 3 months (p = 0.03). At 6 months, serum albumin in the IDPN group was persistently higher than baseline (p = 0.04). Neither volume overload nor uncontrolled hyperglycemia was found throughout the study. In conclusion, a 3-month IDPN supplementation demonstrated a significant increase in serum albumin, body weight, spontaneous oral intake, and MIS; and appeared to be superior to continuing intensive dietary counselling among HD patients intolerable to ONS. The impacts of IDPN therapy on clinical outcomes may require larger scale with longer period of study.

Meal timing and frequency implications in the development and prognosis of chronic kidney disease

Patients with chronic kidney disease (CKD) have a higher risk of death than the general population, the main cause being cardiovascular disease (CVD). Nutrition plays a key role in the prevention and treatment of CVD and kidney diseases. Currently, new evidence reinforces the importance of specific foods and general dietary patterns rather than isolated nutrients for cardiovascular risk. In addition, dietary patterns and healthy eating habits seem extremely relevant in decreasing risk factors. Epidemiologic and clinical intervention studies have suggested that late-night dinner and skipping breakfast are associated with an increased risk of obesity, insulin resistance, and CVD. In CKD, despite important changes in nutritional counseling in recent decades, less attention has been paid to meal timing and frequency. Therefore, the purpose of this review is to discuss the evidence of meal timing and frequency in CKD development and prognosis, presented under three main topics: risk of developing CKD, importance of dietary habits, and implications of fasting.

Associations Between Blood Trace Element Levels and Nutritional Status in Maintenance Hemodialysis

OBJECTIVE(S)

We aimed to investigate the associations between blood trace element levels and nutritional status in patients undergoing maintenance hemodialysis (MHD).

METHODS

This cross-sectional study included patients undergoing MHD who were treated at our center in September 2019. Clinical and demographic data and blood samples were collected before hemodialysis sessions, and the levels of manganese, lead, selenium, zinc, and copper were measured by inductively coupled plasma mass spectrometry. The Simplified Nutritional Appetite Questionnaire scale was used to assess patient appetite. Skinfold thickness, bicep circumference, upper arm muscle circumference, 7-point Subjective Global Assessment, Nutritional Risk Screening 2002 (NRS 2002), and Geriatric Nutritional Risk Index (GNRI) were used to assess patient nutritional status. Univariate and multivariate logistic regression analyses were performed to study the relationship between trace elements and nutritional indicators.

RESULTS

In total, 118 patients (64 males and 54 females) were included, with a median dialysis vintage of 34.0 months (16.0-54.5 months) and an average age of 63.20 ± 14.26 years. Malnourished patients, as defined by the GNRI, Subjective Global Assessment, and NRS 2002, accounted for 28.0%, 49.2%, and 26.3% of enrolled patients, respectively. The multivariate binary logistic regression showed that higher blood copper levels were independently associated with nutritional risk defined as GNRI ≤91.2 (odds ratio [OR] = 1.003, 95% confidence interval [CI] = 1.000-1.006; P = .020), whereas lower blood zinc levels (OR = 0.634, 95% CI = 0.439-0.916; P = .015), blood zinc < 4.220 mg/L (OR = 3.723, 95% CI = 1.274-10.879; P = .016), lower blood selenium levels (OR = 0.959, 95% CI = 0.929-0.990; P = .010), and blood selenium < 85 μg/L (OR = 5.568, 95% CI = 1.039-29.840; P = .045) were independently associated with a nutritional risk defined as NRS 2002 ≥ 3.

CONCLUSION(S)

Higher levels of blood copper and lower levels of blood zinc and selenium were independently associated with higher nutritional risk in MHD patients.

Impact of health-related quality of life on survival after dialysis initiation: a prospective cohort study in Korea

Background

The effect of each health-related quality of life (HRQOL) component on hemodialysis prognosis has not been well studied. We aimed to investigate the clinical factors associated with HRQOL and the effect of HRQOL after dialysis initiation on long-term survival in an Asian population.

Methods

A total of 568 hemodialysis patients were included from a nationwide prospective cohort study. HRQOL was evaluated using the Kidney Disease Quality of Life (KDQOL) Short FormTM 1.3 at 3 months after dialysis initiation. The effect of each KDQOL item score on mortality was analyzed. Multivariable Cox analysis was performed after adjusting for age, sex, modified Charlson comorbidity index, and causes of primary kidney disease.

Results

Old age, diabetes mellitus, high comorbidities, and low serum albumin levels were associated with poor physical health status. Decreased urine output was associated with both poor physical and mental health status. The scores of 3 indices in the kidney disease domain (effect of kidney disease, social support, and dialysis staff encouragement) showed significant associations with mortality, as did the 3 indices (physical function, physical role limitation, and body pain) in the physical health domain. Neither the 4 indices in the mental health domain nor the mental composite score showed a significant association with mortality. However, a high physical composite score was associated with decreased overall patient mortality (P = 0.003). The effect of physical composite score on survival was prominent among young or middle-aged groups.

Conclusion

Poor physical health status 3 months after hemodialysis start correlates significantly with overall mortality.

Eating during the Hemodialysis Session: A Practice Improving Nutritional Status or a Risk Factor for Intradialytic Hypotension and Reduced Dialysis Adequacy?

Historically, eating during the hemodialysis treatment has been associated with increased risk for adverse intradialytic symptoms and events, risks that have resulted in the implementation of restrictive in-center nutrition policies. Recent studies, however, have recorded a shift in clinical practice with a higher proportion of physicians following the view that administration of intradialytic meals and supplements represents a simple and effective approach to enhance caloric intake and improve nutritional status among patients on hemodialysis. This shift towards less restrictive in-center nutrition practices is mainly supported by evidence from observational studies associating intradialytic nutritional supplementation with improvements in protein-energy wasting, inflammatory state, and health-related quality of life. In sharp contrast, earlier and recent interventional studies have documented that feeding during the hemodialysis treatment provokes a rapid postprandial decline in blood pressure and raises the incidence of symptomatic intradialytic hypotension. Furthermore, other studies have shown that postprandial redistribution in intravascular volume and enhanced blood supply to the gastrointestinal circulation may interfere with the adequacy of the delivered hemodialysis. Those who defend the position that intradialytic nutritional support is beneficial do not dispute the physiology of postprandial hemodynamic response, but they argue against its clinical significance. In this article, we provide an overview of studies that explored the effect of eating during the hemodialysis treatment on intradialytic hemodynamic stability and adequacy of the delivered hemodialysis. We reason that these risks have important clinical implications that are not counteracted by anticipated benefits of this strategy on caloric intake and nutritional status.

Intradialytic Nutrition and Hemodialysis Prescriptions: A Personalized Stepwise Approach

Dialysis and nutrition are two sides of the same coin—dialysis depurates metabolic waste that is typically produced by food intake. Hence, dietetic restrictions are commonly imposed in order to limit potassium and phosphate and avoid fluid overload. Conversely, malnutrition is a major challenge and, albeit to differing degrees, all nutritional markers are associated with survival. Dialysis-related malnutrition has a multifactorial origin related to uremic syndrome and comorbidities but also to dialysis treatment. Both an insufficient dialysis dose and excessive removal are contributing factors. It is thus not surprising that dialysis alone, without proper nutritional management, often fails to be effective in combatting malnutrition. While composite indexes can be used to identify patients with poor prognosis, none is fully satisfactory, and the definitions of malnutrition and protein energy wasting are still controversial. Furthermore, most nutritional markers and interventions were assessed in hemodialysis patients, while hemodiafiltration and peritoneal dialysis have been less extensively studied. The significant loss of albumin in these two dialysis modalities makes it extremely difficult to interpret common markers and scores. Despite these problems, hemodialysis sessions represent a valuable opportunity to monitor nutritional status and prescribe nutritional interventions, and several approaches have been tried. In this concept paper, we review the current evidence on intradialytic nutrition and propose an algorithm for adapting nutritional interventions to individual patients.

[Nutrition in chronic kidney disease]

INTRODUCTION

Chronic kidney disease patients often also present protein-calorie malnutrition, and it is a powerful predictor of morbidity and mortality. In this article, causes and management are shown, highlighting oral and parenteral nutritional supplementation, especially during dialysis process.

Use of Intradialytic Parenteral Nutrition in Patients Undergoing Hemodialysis

Intradialytic parenteral nutrition (IDPN) is a form of supplemental nutrition used to treat patients with malnutrition who receive hemodialysis. Once the diagnosis of malnutrition is made in such patients, encouragement of oral intake is the first-line treatment. If this fails, then enteral or parenteral nutrition may be needed. This review examines the literature on the use of IDPN and summarizes the current recommendations. There is considerable controversy over indications and benefits of IDPN, and well-controlled, long-term studies are needed to help tease out these issues. In the interim, clinical judgment should be used when considering IDPN for individual patients.

Frailty and chronic kidney disease: current evidence and continuing uncertainties

Frailty, the state of increased vulnerability to physical stressors as a result of progressive and sustained degeneration in multiple physiological systems, is common in those with chronic kidney disease (CKD). In fact, the prevalence of frailty in the older adult population is reported to be 11%, whereas the prevalence of frailty has been reported to be greater than 60% in dialysis-dependent CKD patients. Frailty is independently linked with adverse clinical outcomes in all stages of CKD and has been repeatedly shown to be associated with an increased risk of mortality and hospitalization. In recent years there have been efforts to create an operationalized definition of frailty to aid its diagnosis and to categorize its severity. Two principal concepts are described, namely the Fried Phenotype Model of Physical Frailty and the Cumulative Deficit Model of Frailty. There is no agreement on which frailty assessment approach is superior, therefore, for the time being, emphasis should be placed on any efforts to identify frailty. Recognizing frailty should prompt a holistic assessment of the patient to address risk factors that may exacerbate its progression and to ensure that the patient has appropriate psychological and social support. Adequate nutritional intake is essential and individualized exercise programmes should be offered. The acknowledgement of frailty should prompt discussions that explore the future care wishes of these vulnerable patients. With further study, nephrologists may be able to use frailty assessments to inform discussions with patients about the initiation of renal replacement therapy.

Intradialytic Parenteral Nutrition in Pediatrics

Children with end-stage renal disease (ESRD) on hemodialysis are at increased risk for malnutrition. Aggressive nutrition intervention such as intradialytic parenteral nutrition (IDPN) should be considered to prevent further co-morbidities and mortality associated with malnutrition when other interventions fail. IDPN is a non-invasive method of providing nutrition to malnourished hemodialysis (HD) patients via the HD access throughout the HD treatment. Although the evidence on the long-term benefits of IDPN is scant in pediatrics, there is evidence that it improves metabolic parameters and nutritional status. In this paper, therapy with IDPN including indications, goals of therapy, and elements to monitor will be described. In addition, a practice guideline for prescribing IDPN is provided.

Could intradialytic nutrition improve refractory anaemia in patients undergoing haemodialysis?

BACKGROUND

This prospective randomised study was designed to evaluate the efficacy of intradialytic parenteral nutrition (IDPN) therapy in malnourished patients with refractory anaemia.

METHODS

Forty patients who were malnourished with a BMI not greater than 23 (17-23) kg/m² , undergoing regular HD were included. Of those, 20 patients received 500-1000 ml of IDPN at a rate of 250-300 ml/h at each HD session three days per week for six consecutive months. The other 20 patients did not receive IDPN infusion. The malnutrition inflammation score (MIS) and haematological parameters were recorded at baseline and after three and six months.

RESULTS

Mean haemoglobin levels, BMI and serum albumin were significantly increased while MIS was significantly decreased after the 3rd and 6th months of IDPN.

CONCLUSION

IDPN has a good role in improving refractory anaemia by significantly increasing haemoglobin levels, body weight, and serum albumin levels. The intervention also significantly decreases the MIS of patients.

The Diet and Haemodialysis Dyad: Three Eras, Four Open Questions and Four Paradoxes. A Narrative Review, Towards a Personalized, Patient-Centered Approach

The history of dialysis and diet can be viewed as a series of battles waged against potential threats to patients' lives. In the early years of dialysis, potassium was identified as "the killer", and the lists patients were given of forbidden foods included most plant-derived nourishment. As soon as dialysis became more efficient and survival increased, hyperphosphatemia, was identified as the enemy, generating an even longer list of banned aliments. Conversely, the "third era" finds us combating protein-energy wasting. This review discusses four questions and four paradoxes, regarding the diet-dialysis dyad: are the "magic numbers" of nutritional requirements (calories: 30-35 kcal/kg; proteins > 1.2 g/kg) still valid? Are the guidelines based on the metabolic needs of patients on "conventional" thrice-weekly bicarbonate dialysis applicable to different dialysis schedules, including daily dialysis or haemodiafiltration? The quantity of phosphate and potassium contained in processed and preserved foods may be significantly different from those in untreated foods: what are we eating? Is malnutrition one condition or a combination of conditions? The paradoxes: obesity is associated with higher survival in dialysis, losing weight is associated with mortality, but high BMI is a contraindication for kidney transplantation; it is difficult to limit phosphate intake when a patient is on a high-protein diet, such as the ones usually prescribed on dialysis; low serum albumin is associated with low dialysis efficiency and reduced survival, but on haemodiafiltration, high efficiency is coupled with albumin losses; banning plant derived food may limit consumption of "vascular healthy" food in a vulnerable population. Tailored approaches and agreed practices are needed so that we can identify attainable goals and pursue them in our fragile haemodialysis populations.

When Is Parenteral Nutrition Appropriate?

Parenteral nutrition (PN) represents one of the most notable achievements of modern medicine, serving as a therapeutic modality for all age groups across the healthcare continuum. PN offers a life-sustaining option when intestinal failure prevents adequate oral or enteral nutrition. However, providing nutrients by vein is an expensive form of nutrition support, and serious adverse events can occur. In an effort to provide clinical guidance regarding PN therapy, the Board of Directors of the American Society for Parenteral and Enteral Nutrition (ASPEN) convened a task force to develop consensus recommendations regarding appropriate PN use. The recommendations contained in this document aim to delineate appropriate PN use and promote clinical benefits while minimizing the risks associated with the therapy. These consensus recommendations build on previous ASPEN clinical guidelines and consensus recommendations for PN safety. They are intended to guide evidence-based decisions regarding appropriate PN use for organizations and individual professionals, including physicians, nurses, dietitians, pharmacists, and other clinicians involved in providing PN. They not only support decisions related to initiating and managing PN but also serve as a guide for developing quality monitoring tools for PN and for identifying areas for further research. Finally, the recommendations contained within the document are also designed to inform decisions made by additional stakeholders, such as policy makers and third-party payers, by providing current perspectives regarding the use of PN in a variety of healthcare settings.

The Effect of Intradialytic Intralipid Therapy in Pediatric Hemodialysis Patients

OBJECTIVE

Growth of children on maintenance hemodialysis is poor. Oral nutritional supplements are the preferred way to augment nutrition; however, many children have difficulties adhering to prescribed oral supplements. In our unit, we have been utilizing intralipid (IL) therapy as nutritional supplement during hemodialysis sessions. The aim of this study was to assess the safety, efficacy, and benefits of intradialytic IL therapy.

DESIGN

A retrospective chart review.

SUBJECTS

Fifteen pediatric hemodialysis patients receiving intradialytic IL therapy for at least 3 months from July 2011 through July 2014.

MAIN OUTCOME MEASURE

For each patient, anthropometric measurements and laboratory nutritional parameters were compared prior to and at the end of IL therapy. Anthropometric measurements evaluated were dry weight, height, body mass index (BMI), and BMI corrected for height age. Laboratory nutritional parameters evaluated were albumin, normalized protein catabolic rate, predialysis blood urea nitrogen, transferrin, cholesterol, and triglyceride levels. Adverse events during therapy were also noted.

RESULTS

Significant improvement was noted in albumin levels, predialysis blood urea nitrogen, and normalized protein catabolic rate during therapy (P = .02; P = .03; P = .03, respectively). Six patients (37.5%) improved their weight standard deviation score, and eight patients (50%) improved their BMI standard deviation score though not statistically significant (P = .59; P = .9, respectively). No significant side effects were noted.

CONCLUSIONS

Administration of IL alone during hemodialysis is well tolerated with beneficial effects on nutritional parameters. The provision of IL alone is relatively cheap and does not require additional resources. In conjunction with other measures of nutritional support, it can help improve nutritional status of pediatric hemodialysis patients.

Effect of Mealtime During Hemodialysis on Patients' Complications

Introduction: Food intake during hemodialysis increases the risk of problems such as hypotension, nausea, and vomiting in patients undergoing hemodialysis. This study aimed to determine the effect of mealtime during dialysis on the patients' complications. Methods: This is a quasi-experimental study consisted of all eligible hemodialysis patients in Hamadan teaching hospitals. All of 48 patients were selected through census method. The research was conducted in two sessions. At both sessions, patients were kept fasting prior to hemodialysis. In the first session, after one hour and in the second session after two hours of hemodialysis, a meal containing 350 kcal of energy was given to the patients. Blood pressure and intensity of nausea and vomiting was measured and recorded immediately before the start of hemodialysis, and then every half an hour before the termination of the hemodialysis. Results: The results showed that in both sessions, food intake caused a drop in the systolic and diastolic blood pressure, but changes in the mealtime had no effect on the systolic and diastolic blood pressure. Also, statistical test showed that changes in the mealtime had no significant impact on the intensity of nausea and vomiting. Conclusion: Food intake during hemodialysis had no effect on the nausea and vomiting, but caused a drop in the systolic and diastolic blood pressure, the drop continued for one hour and one and a half hour after the meal. It is suggested, mealtime in the early hours of hemodialysis could be better managed during the hemodialysis process.

ESPEN guidelines on definitions and terminology of clinical nutrition

BACKGROUND

A lack of agreement on definitions and terminology used for nutrition-related concepts and procedures limits the development of clinical nutrition practice and research.

OBJECTIVE

This initiative aimed to reach a consensus for terminology for core nutritional concepts and procedures.

METHODS

The European Society of Clinical Nutrition and Metabolism (ESPEN) appointed a consensus group of clinical scientists to perform a modified Delphi process that encompassed e-mail communication, face-to-face meetings, in-group ballots and an electronic ESPEN membership Delphi round.

RESULTS

Five key areas related to clinical nutrition were identified: concepts; procedures; organisation; delivery; and products. One core concept of clinical nutrition is malnutrition/undernutrition, which includes disease-related malnutrition (DRM) with (eq. cachexia) and without inflammation, and malnutrition/undernutrition without disease, e.g. hunger-related malnutrition. Over-nutrition (overweight and obesity) is another core concept. Sarcopenia and frailty were agreed to be separate conditions often associated with malnutrition. Examples of nutritional procedures identified include screening for subjects at nutritional risk followed by a complete nutritional assessment. Hospital and care facility catering are the basic organizational forms for providing nutrition. Oral nutritional supplementation is the preferred way of nutrition therapy but if inadequate then other forms of medical nutrition therapy, i.e. enteral tube feeding and parenteral (intravenous) nutrition, becomes the major way of nutrient delivery.

CONCLUSION

An agreement of basic nutritional terminology to be used in clinical practice, research, and the ESPEN guideline developments has been established. This terminology consensus may help to support future global consensus efforts and updates of classification systems such as the International Classification of Disease (ICD). The continuous growth of knowledge in all areas addressed in this statement will provide the foundation for future revisions.

Nutrition, vitamin D, and health outcomes in hemodialysis: time for a feeding frenzy?

PURPOSE OF REVIEW

The role of nutrition and nutritional supplementation in dialysis recently has been reinvigorated, with small clinical trials exploring surrogate outcomes and larger epidemiologic studies generating treatment hypotheses requiring further study. The present review focuses on major aspects of nutrition and outcomes in hemodialysis patients: protein and calorie intake and nutritional vitamin D supplementation.

RECENT FINDINGS

Building on data from small studies, two large, quasi-experimental cohort studies showed significant mortality benefits associated with oral nutritional supplements provided during dialysis, suggesting potential options for ameliorating the protein-energy wasting that is common in dialysis patients and associated with poor outcomes. Multiple cohort studies suggest, both in the general population and in dialysis, that higher 25(OH) vitamin D levels are associated with improved outcomes; however, no major mortality trials exist in dialysis, and the smaller, surrogate studies conducted to date have been disappointing, showing no consistent benefits in surrogate outcomes including inflammation and anemia, despite appropriate responses of vitamin D levels to repletion.

SUMMARY

Nutritional interventions are attractive options for improving outcomes in dialysis patients. Nutritional protein supplements have considerable promise, but require further study, preferably in a large, generalizable pragmatic trial. Small nutritional vitamin D supplementation trials in dialysis have had disappointing results. In the absence of new data, there appears to be no role for routine assessment or repletion of 25(OH) vitamin D deficiency or insufficiency in dialysis.

The Effects of Parenteral Amino Acid Therapy on Protein Carbamylation in Maintenance Hemodialysis Patients

OBJECTIVE

Protein carbamylation is a urea-driven post-translational protein modification associated with mortality in dialysis patients. Free amino acids (AAs) are competitive inhibitors of protein carbamylation and animal studies suggest increasing AA concentrations reduces carbamylation burden. We hypothesized that AA therapy in maintenance hemodialysis patients would reduce carbamylation, carrying the potential to improve clinical outcomes.

DESIGN

Prospective pilot clinical trial (NCT1612429).

SETTING

The study was conducted from March 2013 to March 2014 in outpatient dialysis facilities in the Boston metropolitan area.

SUBJECTS AND INTERVENTION

We enrolled 23 consecutively consenting hemodialysis subjects, infusing the first 12 individuals with 250 cc of AAs 3 times per week postdialysis over 8 weeks. The remaining 11 subjects served as controls.

MAIN OUTCOME MEASURE

Change in carbamylated albumin (C-Alb), a measure of total body carbamylation burden, between baseline and 8 weeks was the primary outcome.

RESULTS

The treated and control groups had similar clinical characteristics and similar baseline C-Alb levels (mean ± SE 9.5 ± 2.4 and 9.3 ± 1.3 mmol/mol, respectively; P = .61). The treated arm showed a significant reduction in C-Alb compared with controls at 4 weeks (8.4% reduction in the treated arm vs. 4.3% increase in controls; P = .03) and the effect was greater by 8 weeks (15% reduction in the treated vs. 1% decrease in controls; P = .01).

CONCLUSION

In this pilot study, AA therapy appeared safe and effective at reducing C-Alb levels in hemodialysis patients compared with no treatment. The impact of reduced protein carbamylation on clinical outcomes should be further investigated.

Nutritional predictors of early mortality in incident hemodialysis patients

PURPOSE

Low serum albumin concentration and low dietary protein intake are associated with protein-energy wasting (PEW) and higher mortality in maintenance hemodialysis patients. The role of these nutritional markers is less clear in clinical outcomes of the first several months of dialysis therapy, where mortality is exceptionally high.

METHODS

In a cohort of 17,445 incident hemodialysis patients, we examined variation in serum albumin and the normalized protein catabolic rate (nPCR), a surrogate of dietary intake, and quarterly mortality in the first 2 years of dialysis therapy. Cox proportional hazard models were fitted to estimate the association between mortality and combined albumin/nPCR categories for eight quarters. We investigated the associations between mortality and baseline and subsequent serum albumin levels per cohort quarter as well as changes in albumin and nPCR over time.

RESULTS

Patients were 64 ± 15 years old (mean ± SD) and included 45 % women, 24 % African Americans and 58 % diabetics. Correlations between quarterly serum albumin and nPCR varied from 0.18 to 0.25. Serum albumin <3.5 g/dL was consistently associated with high mortality as was nPCR <1 g/kg/day (except for qtr1). Low serum albumin and nPCR greater than 0.2 g/dLg/dL or g/kg/day, respectively, were associated with increased risk of death. Quarterly rise in nPCR (>+0.2 g/kg/day) showed reverse effect on mortality from the 2nd to the last quarter.

CONCLUSIONS

Low serum albumin and nPCR are associated with mortality. A rapid rise in nPCR by the end of the second year may indicate pre-existing PEW.

Let them eat during dialysis: an overlooked opportunity to improve outcomes in maintenance hemodialysis patients

In individuals with chronic kidney disease, surrogates of protein-energy wasting, including a relatively low serum albumin and fat or muscle wasting, are by far the strongest death risk factor compared with any other condition. There are data to indicate that hypoalbuminemia responds to nutritional interventions, which may save lives in the long run. Monitored, in-center provision of high-protein meals and/or oral nutritional supplements during hemodialysis is a feasible, inexpensive, and patient-friendly strategy despite concerns such as postprandial hypotension, aspiration risk, infection control and hygiene, dialysis staff burden, diabetes and phosphorus control, and financial constraints. Adjunct pharmacologic therapies can be added, including appetite stimulators (megesterol, ghrelin, and mirtazapine), anabolic hormones (testosterone and growth factors), antimyostatin agents, and antioxidative and anti-inflammatory agents (pentoxiphylline and cytokine modulators), to increase efficiency of intradialytic food and oral supplementation, although adequate evidence is still lacking. If more severe hypoalbuminemia (<3.0 g/dL) not amenable to oral interventions prevails, or if a patient is not capable of enteral interventions (e.g., because of swallowing problems), then parenteral interventions such as intradialytic parenteral nutrition can be considered. Given the fact that meals and supplements during hemodialysis would require only a small fraction of the funds currently used for dialysis patients this is also an economically feasible strategy.

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.

Effects of a new mixture of essential amino acids (Aminotrofic(®)) in malnourished haemodialysis patients

The aim of this study was to verify the clinical efficacy of a diet associated with already commercially available oral amino acid functional cluster (AFC) compared to the administration of a diet associated with a nitrogen protein-based supplement (casein) in antagonizing malnutrition in patients with Chronic renal failure (CRF) undergoing haemodialysis. The secondary aim was to assess the changes in protein levels during the acute phase such as the expression of inflammatory cytokines. Twenty patients in haemodialysis aged between 18 and 85 of both genders (13 m, 7f) were recruited, randomized and divided into two groups and treated for 4 months respectively with: (1) oral AFC supplement (*)8 g/die: group A, and (2) oral supplementation of a protein nitrogenous mixture compared to AFC with a casein protein source) of 6.6 g: group P. During the initial assessment and thereafter on a monthly basis all patients underwent the following: Dietary recall 24 h; Anthropometric: Weight, height, BMI, expected dry weight, actual weight; Biochemical: Albumin, transferrin, Na, K, Cl, Ca, P, Mg, long-interval creatinine (Aminotrofic(®): Errekappa Euroterapici, Milano) pre-albumin, α1 acid glycoprotein, C reactive protein (CRP), protein nitrogen appearance (PNA); Instrumental: Handgrip strength evaluation, Calorimetry by means of Armband, Bio-impedance analysis (BIA), Spitzer Index (quality of life), Subjective Global Assessment Generated by the patient (PG SGA). Considering the nutritional parameters, no significant differences concerning dry weight emerged between the beginning (T0) and the end (T4) (weight A to T0: kg 64.41 ± 6.34; weight A to T4: kg 64.51 ± 7.05: P = NS; weight P to T0: kg 60.17 ± 11.94; weight P to T4: kg 59.86 ± 11.43: P = NS); biochemical parameters, significant differences were observed only for two parameters: pre-albumin (Pre-albumin A to T0 30.12 ± 7.23; Pre-albumin A to T4: 28.91 ± 5.8; Pre-albumin P to T0 22.51 ± 6.04; Pre-albumin P to T4: 26.10 ± 9.82), and Transferrin (Transferrin A to T0 171.77 ± 28.87 mg/dL, Transferrin A to T4: 181.44 ± 38.83 mg/dL: P < 0.005; Transferrin P to T0 160.29 ± 27.46 mg/dL, Transferrin P to T4: 146.57 ± 24.96 mg/dL: P < 0.005), but not in other parameters. From a nutritional perspective, after 4 months of treatment an increase in protein synthesis was noted in group A compared to group P which was proved by the significant increase of transferrin. This pilot study suggests the AFC oral supplementation may represent a valid alternative to intradialytic parenteral treatment and may also allow for an improvement in blood chemical values and nutritional status.

Modifiable risk factors for early mortality on hemodialysis

Data of incident hemodialysis patients from 2001 to 2007 were abstracted from The Renal Disease Registry (TRDR) from central Ontario, Canada and followed until December 2008 to determine 90-day mortality rates for incident hemodialysis patients. Modifiable risk factors of early mortality were determined by a Cox model. In total, 876 of 4807 incident patients died during their first year on dialysis; 304 (34.7%) deaths occurred within the first 90 days of dialysis initiation. The majority of deaths were attributed to a cardiovascular event or infection and more likely occurred in older patients and those with cardiovascular co-morbidities. Of potentially modifiable risk factors, low body mass index (<18.5), a surrogate for malnutrition, was a strong predictor of early mortality [adjusted hazard ratio (HR) 4.22 (CI: 3.12–5.17)]. Also, central venous catheter use was associated with a 2.40 fold increase risk of death (CI: 1.4–3.90). Patients who attended a multidisciplinary pre-dialysis clinic were less likely to die (HR: 0.60, CI: 0.47–0.78). The first 90 days after initiation of dialysis is a period of especially high risk of death. We have identified potentially modifiable risk factors in vascular access type, pre-dialysis care and nutritional status.

Diets and enteral supplements for improving outcomes in chronic kidney disease

Protein-energy wasting (PEW), which is manifested by low serum levels of albumin or prealbumin, sarcopenia and weight loss, is one of the strongest predictors of mortality in patients with chronic kidney disease (CKD). Although PEW might be engendered by non-nutritional conditions, such as inflammation or other comorbidities, the question of causality does not refute the effectiveness of dietary interventions and nutritional support in improving outcomes in patients with CKD. The literature indicates that PEW can be mitigated or corrected with an appropriate diet and enteral nutritional support that targets dietary protein intake. In-center meals or oral supplements provided during dialysis therapy are feasible and inexpensive interventions that might improve survival and quality of life in patients with CKD. Dietary requirements and enteral nutritional support must also be considered in patients with CKD and diabetes mellitus, in patients undergoing peritoneal dialysis, renal transplant recipients, and in children with CKD. Adjunctive pharmacological therapies, such as appetite stimulants, anabolic hormones, and antioxidative or anti-inflammatory agents, might augment dietary interventions. Intraperitoneal or intradialytic parenteral nutrition should be considered for patients with PEW whenever enteral interventions are not possible or are ineffective. Controlled trials are needed to better assess the effectiveness of in-center meals and oral supplements.

Quality-of-life and mortality in hemodialysis patients: roles of race and nutritional status

BACKGROUND AND OBJECTIVES

Maintenance hemodialysis (MHD) patients often have protein-energy wasting, poor health-related quality of life (QoL), and high premature death rates, whereas African-American MHD patients have greater survival than non-African-American patients. We hypothesized that poor QoL scores and their nutritional correlates have a bearing on racial survival disparities of MHD patients.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We examined associations between baseline self-administered SF36 questionnaire-derived QoL scores with nutritional markers by multivariate linear regression and with survival by Cox models and cubic splines in the 6-year cohort of 705 MHD patients, including 223 African Americans.

RESULTS

Worse SF36 mental and physical health scores were associated with lower serum albumin and creatinine levels but higher total body fat percentage. Spline analyses confirmed mortality predictability of worse QoL, with an almost strictly linear association for mental health score in African Americans, although the race-QoL interaction was not statistically significant. In fully adjusted analyses, the mental health score showed a more robust and linear association with mortality than the physical health score in all MHD patients and both races: death hazard ratios for (95% confidence interval) each 10 unit lower mental health score were 1.12 (1.05-1.19) and 1.10 (1.03-1.18) for all and African American patients, respectively.

CONCLUSIONS

MHD patients with higher percentage body fat or lower serum albumin or creatinine concentration perceive a poorer QoL. Poor mental health in all and poor physical health in non-African American patients correlate with mortality. Improving QoL by interventions that can improve the nutritional status without increasing body fat warrants clinical trials.

[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.