Malnutrition in Hemodialysis Patients: What Therapy?

Association between oral frailty and nutritional status among hemodialysis patients aged ≥50 years

AIM

Malnutrition is a prevalent health issue among hemodialysis patients. Oral frailty, a condition characterized by impairments in multiple oral health aspects and functions, has been associated with nutritional status in the general population. We aimed to determine whether oral frailty was associated with nutritional status in hemodialysis patients aged ≥50 years. Our secondary aim was to determine the prevalence of oral frailty in this population.

METHODS

This cross-sectional study included hemodialysis patients who were admitted to a single medical center. According to the Oral Frailty 5-item Checklist, oral frailty is characterized by the presence of two or more of the following criteria: (i) fewer teeth, (ii) difficulty in chewing, (iii) difficulty in swallowing, (iv) dry mouth, and (v) low articulatory oral motor skills. Patients' nutritional status was assessed using the Geriatric Nutritional Risk Index (GNRI). Multivariable ordinal logistic regression analysis was performed to assess the association between oral frailty and nutritional status (classified into three categories according to the GNRI: >98, 92-98, and <92).

RESULTS

In total, 152 hemodialysis patients (55 women and 97 men) with a mean age of 70.4 years were included. The prevalence of oral frailty was 61.2%. After adjusting for health characteristics and sociodemographic background, oral frailty was associated with poor nutritional status according to the GNRI (odds ratio = 2.04, 95% confidence interval = 1.02-4.09).

CONCLUSIONS

In this study, approximately 60% of hemodialysis patients aged ≥50 years exhibited oral frailty, and hemodialysis patients with oral frailty had poor nutritional status according to the GNRI. Geriatr Gerontol Int 2024; ••: ••-••.

The triglyceride-glucose index as a novel marker associated with sarcopenia in non-diabetic patients on maintenance hemodialysis

Objective

Sarcopenia is a common complication in patients with end-stage kidney disease. Insulin resistance is present in non-diabetic patients undergoing maintenance hemodialysis (MHD) and is an important factor leading to sarcopenia. The triglyceride–glucose (TyG) index, a reliable indicator for evaluating insulin resistance, is widely used in clinical practice. The present study investigated the association between the TyG index and sarcopenia in non-diabetic patients undergoing MHD.

Methods

Relevant clinical data of non-diabetic patients undergoing MHD at our center were collected. The TyG index was calculated using the following formula: ln(fasting triglycerides(mg/dL)×fasting blood glucose(mg/dL)/2). Multivariate logistic regression analyses were used to evaluate the associations. The receiver-operating characteristic curve was used to analyze the predictive value of the TyG index in sarcopenia.

Results

Of the 142 patients undergoing MHD who were included, 75 (52.82%) were men, the mean age was 54.05 ± 13.97 years, and 40 (28.17%) patients satisfied the diagnostic criteria for sarcopenia. The TyG index of participants with sarcopenia was higher compared with those without sarcopenia (8.83 ± 0.45 vs. 8.49 ± 0.50, p < 0.001). The prevalence of sarcopenia increased with increasing TyG index tertile (T1, 8.51%; T2, 31.91%; T3, 43.75%; p = 0.001). Logistic regression analysis indicated that the TyG index was an independent risk factor for sarcopenia (odds ratio, 4.21 [95% confidence interval, 1.85–9.59], p = 0.001).

Conclusion

A higher TyG index was associated with an increased risk of sarcopenia in non-diabetic patients undergoing MHD; it may be used as a novel marker to reflect the presence of sarcopenia.

Total body water/fat-free mass ratio as a valuable predictive parameter for mortality in maintenance hemodialysis patients

Hydration of fat-free mass (FFM), defined as the ratio of total body water (TBW) to FFM (TBW/FFM), is stable at 0.739 in adult mammals. However, an increase in the TBW/FFM ratio is common in hemodialysis (HD) patients. This study aimed to evaluate the determinants of TBW/FFM and investigate its predictive value for the prognosis of all-cause mortality in HD patients. We enrolled patients undergoing maintenance HD between July 2020 and May 2021. All patients were prospectively followed until death, HD dropout, or until the end of the study (November 1, 2021). A forward stepwise multivariable linear regression analyses was performed to test the independent relationship between TBW/FMM and other clinical variables. Receiver operating characteristic (ROC) analysis was used to discriminate the TBW/FFM with respect to 180-day mortality. Of the 106 patients, 42 had elevated TBW/FFM levels. Multiple linear regression analysis revealed that the TBW/FFM ratio was significantly associated with extracellular water (ECW)/TBW (standardized regression coefficient [β = 1.131, P < .001], phase angle (PhA) [β = 0.453, P < .001], and sex (β = 0.440, P < .001). We calculated the ROC curve (AUC) of TBW/FFM, ECW, ECW/TBW, and intracellular water (ICW) to compare the discriminatory capacities of these parameters in predicting 180-day mortality. The AUC for TBW/FFM (AUC = 0.849; 95% CI, 0.745-0.953) exhibited better discriminatory potential than ECW (AUC = 0.562; 0.410-0.714), although it had a similar predictive potential as the ECW/TBW ratio (AUC = 0.831; 0.731-0.932). High TBW/FFM can be used as a valuable prognostic index for predicting all-cause mortality in patients on HD.

Mammalian Target of Rapamycin Inhibitors and Wound Healing Complications in Kidney Transplantation: Old Myths and New Realities

Mammalian target of rapamycin inhibitors (mTOR-I) lacks nephrotoxicity, has antineoplastic effects, and reduces viral infections in kidney transplant recipients. Earlier studies reported a significant incidence of wound healing complications and lymphocele. This resulted in the uncomfortable willingness of transplant clinicians to use these agents in the immediate posttransplant period. As evidence and experience evolved over time, much useful information became available about the optimal use of these agents. Understandably, mTOR-I effects wound healing through their antiproliferative properties. However, there are a lot of other immunological and nonimmunological factors which can also contribute to wound healing complications. These risk factors include obesity, uremia, increasing age, diabetes, smoking, alcoholism, and protein-energy malnutrition. Except for age, the rest of all these risk factors are modifiable. At the same time, mycophenolic acid derivatives, steroids, and antithymocyte globulin (ATG) have also been implicated in wound healing complications. A lot has been learnt about the optimal dose of mTOR-I and their trough levels, its combinations with other immunosuppressive medications, and patients' profile, enabling clinicians to use these agents appropriately for maximum benefits. Recent randomized control trials have further increased the confidence of clinicians to use these agents in immediate posttransplant periods.

Refeeding syndrome in haemodialysis patients

Nutritional therapies have shown to be efficacious and efficient, despite the overall low level of evidence. It however hides the risk of refeeding syndrome in catabolic malnourished patients. Refeeding syndrome is the metabolic response due to the switch from a starvation to a fed state in the initial phase of nutritional therapy in patients who were severely malnourished or metabolically stressed due to severe illness. Here we describe two cases of chronic kidney disease patients on maintenance haemodialysis, who developed refeeding syndrome. Both the patients had tuberculosis and were severely malnourished with subjective global Assessment (SGA) of grade C. Timely diagnosis and proper management leads to good outcome.

Significance of nutrition in hemodialysis patients with peripheral arterial disease evaluated by skin perfusion pressure

Background

Peripheral artery disease (PAD) is a serious complication in hemodialysis (HD) patients. Low skin perfusion pressure (SPP) is a useful marker for detecting PAD. Malnutrition is an important cause of intractable complications. We examined the relationship between low SPP and various indicators of nutritional status.

Methods

A total of 120 patients on maintenance HD were enrolled for SPP measurement. SPP was measured at the soles of both feet during HD, and patients were divided into low SPP (L-SPP) and normal SPP (N-SPP) groups by 50 mmHg. The following values were determined by averaging four blood samples taken before SPP measurements every 3 months for one year: hemoglobin, total protein, albumin (Alb), total cholesterol, urea nitrogen, creatinine (Cr), potassium, calcium, phosphate, intact parathyroid hormone, iron (Fe), transferrin saturation (T-SAT), and C-reactive protein (CRP). We calculated the percent Cr production rate, dialysis index (Kt/V), normalized protein catabolic rate (nPCR), geriatric nutritional risk index (GNRI), and estimated salt intake using the required formulas. In addition, the age, body mass index, and presence of diabetes mellitus (DM) were compared between both groups along with all other measurements. Data were expressed as the mean ± standard deviation or median with interquartile range as appropriate. Differences in continuous variables between the two groups were analyzed by Student’s t-test or Wilcoxon’s rank-sum test, as appropriate. Multivariate logistic analysis and receiver operating curve (ROC) analysis were performed for significant variables. The results were expressed as odds ratios with respective 95% confidence intervals (CIs).

Results

The enrolled patients were 82 men and 38 women, with a mean age of 66.9 ± 13.3 years and HD duration of 4.76 (2.13–12.28) years (median interquartile range). Twenty patients belonged to the L-SPP group, suggesting PAD. Comparison between the L-SPP and N-SPP groups showed significant differences in age, Cr, Fe, T-SAT, CRP, nPCR, GNRI, DM, and estimated salt intake. When the GNRI, estimated salt intake, CRP, and DM were applied as independent variables for multiple logistic regression analysis, the GNRI (odds ratio: 0.857, 95% CI 0.781–0.941, p = 0.001), CRP (2.406, 1.051–3.980, p = 0.035), and DM (9.194, 2.497–33.853, p = 0.001) were found to be significant for L-SPP, and a cutoff level of 92.1 (sensitivity 80%, specificity 72%, AUC: 0.742, 95% CI 0.626–0.858, p = 0.001) in the GNRI obtained by ROC was consistent with the risk index in the elderly presented previously.

Conclusions

SPP measurement is an essential tool for detecting high-risk PAD in maintenance HD, which is affected by malnutrition, DM, and inflammation. The GNRI is important for the determination of malnutrition.

Gastrointestinal symptom burden and dietary intake in patients with chronic kidney disease

BACKGROUND

Gastrointestinal (GI) symptoms can present a significant burden to patients with chronic kidney disease (CKD) but the reported prevalence is inconsistent.

OBJECTIVE

To examine the GI burden and dietary intake in patients with CKD with or without dialysis.

METHODS

This was a cross-sectional study of 216 adults, recruited from outpatient and dialysis clinics, with CKD stage 4 or 5 not receiving dialysis (CKD-ND), or receiving haemodialysis (HD) or peritoneal dialysis (PD). Three questionnaires were administered: the Bristol Stool Form Scale (BSFS); a modified Gastrointestinal Symptom Rating Scale and a short Food Frequency Questionnaire. Outcomes were stool frequency and consistency, GI symptoms and dietary intake.

RESULTS

Data were collected from 216 patients (mean age, 63 years [95% CI: 61, 65]; 63% males; CKD-ND: n = 134; HD: n = 67; PD: n = 15). Mean stool frequency for all groups was one bowel action per day (p = .45) and consistency was normal (BSFS type 4, p = .95). Overall GI symptom burden was low but several symptoms occurred at least "most of the time" including "tiredness/lethargy" (54% of participants), "reduced appetite" (29%), "early satiety" (25%) and "change in taste" (15%). Low intakes of fresh fruit, vegetables, whole-grains and legumes were found. No associations were observed between diet and GI symptoms.

CONCLUSION

The overall GI symptom burden was low, but >15% of participants reported several symptoms as occurring most to all of the time. Low intakes of fresh fruit, vegetables, whole-grains and legumes were observed in all CKD patients.

[Refeeding syndrome : Pathophysiology, treatment and which rheumatic patients are particularly at risk]

Rheumatische Krankheiten können über verschiedene Mechanismen zu einer Mangelernährung, also einer nicht ausreichenden Deckung des Bedarfs an Energie, Proteinen, Elektrolyten oder anderen Nährstoffen, führen. Bei Wiederbeginn mit vollwertiger Ernährung nach einer Phase einer solchen katabolen Stoffwechsellage kommt es zu metabolischen Veränderungen, die in einen akuten Mangel an verfügbaren Elektrolyten und anderen Mikronährstoffen führen und dann lebensbedrohliche Komplikationen auslösen können. Das Auftreten solcher Komplikationen nach Wiederbeginn der Ernährung wird als Refeeding-Syndrom bezeichnet. Mit Wissen um diese Komplikationen, dem adäquaten Wiederbeginn der Ernährung und ggf. einer Überwachung der relevanten Parameter sowie gezielter Supplementierung kann das Refeeding-Syndrom vermieden werden. In dieser Übersichtsarbeit werden die Pathomechanismen des Refeeding-Syndroms erklärt, die Risikofaktoren für das Auftreten des Refeeding-Syndroms – insbesondere unter Betrachtung von rheumatologischen Patienten – identifiziert und die nötige Therapie zur Vermeidung eines Refeeding-Syndroms bei Wiederbeginn der Ernährung dargestellt.

Understanding Development of Malnutrition in Hemodialysis Patients: A Narrative Review

Hemodialysis (HD) majorly represents the global treatment option for patients with chronic kidney disease stage 5, and, despite advances in dialysis technology, these patients face a high risk of morbidity and mortality from malnutrition. We aimed to provide a novel view that malnutrition susceptibility in the global HD community is either or both of iatrogenic and of non-iatrogenic origins. This categorization of malnutrition origin clearly describes the role of each factor in contributing to malnutrition. Low dialysis adequacy resulting in uremia and metabolic acidosis and dialysis membranes and techniques, which incur greater amino-acid losses, are identified modifiable iatrogenic factors of malnutrition. Dietary inadequacy as per suboptimal energy and protein intakes due to poor appetite status, low diet quality, high diet monotony index, and/or psychosocial and financial barriers are modifiable non-iatrogenic factors implicated in malnutrition in these patients. These factors should be included in a comprehensive nutritional assessment for malnutrition risk. Leveraging the point of origin of malnutrition in dialysis patients is crucial for healthcare practitioners to enable personalized patient care, as well as determine country-specific malnutrition treatment strategies.

Association Between Comprehensive Nutritional Scoring System (CNSS) and Outcomes of Continuous Ambulatory Peritoneal Dialysis Patients

BACKGROUND/AIMS

The presence of protein-energy wasting (PEW) among dialysis patients is a crucial risk factor for outcomes. The complicated pathogenesis of PEW makes it difficult to assess and treat. This single-center retrospective study focuses on the association between nutritional markers and the outcomes of continuous ambulatory peritoneal dialysis(CAPD) patients, aiming to establish a practical comprehensive nutritional scoring system for CAPD patients.

METHODS

924 patients who initiated peritoneal dialysis in our center from January 1st,2005 to December 31st,2015 were enrolled. Comprehensive nutritional scoring system(CNSS) was based on items including SGA, BMI, ALB, TC, MAC and TSF. We divide patients into 3 groups according to their CNSS score. Outcomes including mortality, hospitalization days and hospitalization frequency were compared between 3 grades.

RESULTS

The CNSS grade correlated significantly with hospitalization days (P<0.05). Both categorized CNSS grade (HR:0.56; 95% CI:0.41-0.78; P = 0.001) and continuous CNSS score (HR:0.87; 95% CI: 0.80-0.94; P = 0.001) independently protect PD patients from all-cause mortality.

CONCLUSION

CNSS provides an integrated scoring system with significant associations with hospitalization and mortality in PD patients. The CNSS grade differentiates patients with malnutritional risk and independently predicts high risk of morbidity and mortality.

Effect of Personalized Nutritional Counseling on the Nutritional Status of Hemodialysis Patients

This study set out to evaluate the impact of personalized nutritional counseling (PNC) on the nutritional status of hemodialysis (HD) patients. This was an intervention study for 10 months at 2 hospitals. Anthropometric, biochemical, dietary, and body composition parameters were measured at baseline and after 3 and 6 months of PNC. A total of 42 patients (23 men and 19 women) were included. Intake of dietary protein, serum albumin, and cholesterol levels had increased significantly from baseline to month 6 (p < 0.05). Among the bioelectrical impedance analysis (BIA) parameters, both the body cell mass (BCM) and the fat free mass (FFM) had significantly reduced at month 3 compared to baseline (p < 0.05). However, there was no difference between baseline and month 6. We assessed the nutritional status of the subjects using the malnutrition inflammation score (MIS), and divided them into an adequately nourished (AN) and a malnourished (MN) group at baseline. In the subgroup analysis, serum levels of albumin and cholesterol had increased significantly, particularly from baseline to month 6 in the MN group (p < 0.05). This study suggests that consecutive PNC contributed to the improvement of the protein intake, serum levels of albumin, cholesterol and to the delay of muscle wasting, which could also have a positive impact on the nutritional status, particularly in malnourished patients receiving HD treatment.

Assessment of Severity of Malnutrition in Peritoneal Dialysis Patients via Malnutrition: Inflammatory Score

Background

Regarding to the complications of malnutrition in dialysis patients, using an easy and reliable method for evaluating of malnutrition is important in patients with the end-stage renal disease. Based on the effect of inflammatory factors in malnutrition, A new scale has been designed which is called malnutrition-inflammatory scale (MIS). We designed current study to assess the severity of malnutrition in peritoneal dialysis patients in Isfahan via MIS.

Materials and Methods

In this cross-sectional MIS was used for evaluation of malnutrition. MIS includes 10 components: dry weight changes, dietary intake, functional capacity, comorbidity, muscle wasting and loss of subcutaneous fat as well as body mass index (BMI), serum albumin level and total iron binding capacity (TIBC). Each component has four levels of severity from 0 (normal) to 3 (severely abnormal). All analyses were performed using Statistical Package for Social Sciences version 20 (SPSS 20) and P < 0.05 were considered statistically significant.

Results

Results showed no significant difference in MIS between male and female participants. Mean of minimum inhibitory concentration in this study was calculated about 4.1 (MIS <9) which means no or mild malnutrition. Significant correlation between MIS and weight (P < 0.001), BMI (P < 0.001), TIBC (P < 0.001), triglyseride (P = 0.04) and arm circumference (P < 0.001) was seen.

Conclusion

We suggest That MIS is being used as a valuable tool for prevention of fatal outcomes in chronic dialysis patients.

Comparison of malnutrition in hemodialysis and peritoneal dialysis patients and its relationship with echocardiographic findings

Background:

Malnutrition is common in patients with end-stage renal disease (ESRD) who on peritoneal dialysis (PD) or hemodialysis (HD). This study aimed to compare the frequency distribution of malnutrition in HD and PD patients and its relationship with echocardiographic findings.

Materials and Methods:

This is a case–control study. Using the simple random sampling, 109 patients were selected among HD and PD patients based on the inclusion criteria. HD and PD groups included 55 and 54 patients, respectively. The malnutrition-inflammation score (MIS) index was used to assess malnutrition. Echocardiography was performed by a cardiologist. All the data were analyzed by SPSS version 18.

Results:

In this study, 79.6% (43 patients) were in the PD group with MIS <9 (no malnutrition to mild malnutrition) and 20.4% (11 patients) with 9 ≤ MIS ≤ 18 suffered from moderate malnutrition. In the HD group, 72.7% (forty patients) had MIS < 9, 25.5% (14) had 9 ≤ MIS ≤ 18, and 1.8% (one patient) with MIS > 18 suffered from severe malnutrition (P = 0.74). There was no significant relationship between MIS and echocardiographic findings in PD patients (P > 0.05). In the HD group, there was no significant relationship between MIS and echocardiographic findings (P > 0.05), except for aortic and mitral valve insufficiencies (P < 0.05).

Conclusion:

The findings of this study show 27.3% of HD patients had moderate to severe malnutrition. There was a statistically significant relationship between MIS index and aortic and mitral valve insufficiencies in HD patients.

Effect of the omega-3 fatty acid plus vitamin E supplementation on subjective global assessment score, glucose metabolism, and lipid concentrations in chronic hemodialysis patients

SCOPE

This study was conducted to determine the effects of omega-3 fatty acid plus vitamin E supplementation on subjective global assessment (SGA) score and metabolic profiles in chronic hemodialysis (HD) patients.

METHODS AND RESULTS

This randomized double-blind placebo-controlled clinical trial was conducted among 120 chronic HD patients. Participants were randomly divided into four groups to receive: (i) 1250 mg/day omega-3 fatty acid containing 600 mg eicosapentaenoic acid and 300 mg docosahexaenoic acid + vitamin E placebo (n = 30), (ii) 400 IU/day vitamin E + omega-3 fatty acids placebo (n = 30), (iii) 1250 mg omega-3 fatty acids/day + 400 IU/day vitamin E (n = 30), and (iv) omega-3 fatty acids placebo + vitamin E placebo (n = 30) for 12 wk. Fasting blood samples were taken at baseline and after 12-wk intervention to measure metabolic profiles. Patients who received combined omega-3 fatty acids and vitamin E supplements compared with vitamin E, omega-3 fatty acids, and placebo had significantly decreased SGA score (p < 0.001), fasting plasma glucose (p = 0.01), serum insulin levels (p = 0.001), homeostasis model of assessment insulin resistance (p = 0.002), and improved quantitative insulin sensitivity check index (p = 0.006).

CONCLUSION

Omega-3 fatty acids plus vitamin E supplementation for 12 wk among HD patients had beneficial effects on SGA score and metabolic profiles.

Nutrition assessment and risk prediction in dialysis patients-a new integrative score

OBJECTIVE

We developed a quantitative nutritional score, based on biochemical measures, taken as part of monthly routine care. The score can be accomplished within a short time after routine laboratory results completion and identify a monthly change in nutritional status.

DESIGN

A longitudinal observational cohort study

SETTING

The Institute of Nephrology, Wolfson Medical Center, Holon, Israel.

SUBJECTS

A total of 179 hemodialysis patients were followed up for up to 2.5 years after study baseline.

INTERVENTION

The Integrative Clinical Nutrition Dialysis Score (ICNDS) is based on the biochemical measures of albumin, creatinine, urea, cholesterol, C-reactive protein, dialysis adequacy, and weight change. Each parameter is ranked between 1 and 5, with the higher rank derived from recommended National Kidney Foundation Kidney Disease/Dialysis Outcomes and Quality Initiative values and the lower rank indicating deviation from those values. The final ICNDS is the sum of ranks over 7 parameters.

MAIN OUTCOME MEASURE

The Pearson correlation coefficient was calculated for association between subjective global assessment and ICNDS in 63 randomly selected patients. In 179 dialysis patients, the baseline ICNDS, the slope of 3 subsequent monthly ICNDS values, were tested for their correlation with odds of all-cause mortality, hospitalization frequency, length of stay, after 31 months. Spline Cox regression was used to select the best cutoff point, associated with severe mortality risk.

RESULTS

Score results were significantly correlated with nutrition evaluation by subjective global assessment (r = 0.842, P < .01). For a unit increase in baseline score, death odds were significantly decreased (hazard ratio [HR] = 0.929, 95% confidence interval [CI] 0.88-0.974, P < .002). Each unit increase in slope significantly reduced mortality risk (HR = 0.485, 95% CI 0.278-0.847, P < .011). Hospitalization frequency was significantly increased across worsening baseline score (HR = 0.935, 95% CI 0.906-0.964, P < .0001). A 1-unit increase in slope significantly decreased hospitalization (HR = 0.799, 95% CI 0.726-0.881, P < .0001).

CONCLUSIONS

Results confirm that ICNDS is a useful prognostic tool that serves to detect nutrition deterioration at its very beginning.

Comparison of bioimpedance and dual-energy x-ray absorptiometry for measurement of fat mass in hemodialysis patients

BACKGROUND

Fat mass (FM) is measured with dual-energy X-ray absorptiometry (DXA), but is expensive and not portable. Multifrequency bioimpedance spectroscopy (BIS) measures total body water (TBW), intracellular water (ICW) and extracellular water (ECW). FM is calculated by subtracting fat-free mass (FFM) from weight assuming a fractional hydration of FFM of 0.73. Hemodialysis (HD) patients, however, have nonphysiologic expansion of ECW. Our aim was to apply a model to estimate FM in HD patients and controls.

METHODS

We estimated the hydration of FFM in healthy subjects and HD patients with BIS (Impedimed multifrequency) assuming a hydration of 0.73 or using a model allowing ECW and ICW to vary, deriving a value for FM accounting for variances in ECW and ICW. FM was measured by DXA (Hologic Discovery W) in 25 controls and in 11 HD patients. We measured TBW, ECW and ICW with BIS and calculated FM using either weight - TBW/0.73 or with a model accounting for variations in ECW/ICW to estimate FM.

RESULTS

ECW/ICW was greater in HD patients than in controls (0.83 ± 0.08 vs. 0.76 ± 0.04; p = 0.001). FM (kg) measured by DXA or estimated from TBW using constant hydration or accounting for variations in ECW/ICW was not significantly different in controls or in HD patients. Values obtained by all methods correlated (p < 0.001) and none of the Bland-Altman plots regressed (r(2) = 0.00). FM measured by DXA and by BIS in both controls and HD patients combined correlated (r(2) = 0.871).

CONCLUSION

Expansion of ECW in HD patients is statistically significant; however, the effect on hydration of FFM was insufficient to cause significant deviation from values derived using a hydration value of 0.73 within the range of expansion of ECW in the HD patient population studied here.

Nutrition in infants and very young children with chronic kidney disease

Provision of adequate nutrition is a cornerstone of the management of infants and very young children with chronic kidney disease (CKD). Very young children with CKD frequently have poor spontaneous nutritional intake. Because growth depends strongly on nutrition during early childhood, growth in very young children with CKD is often suboptimal. In this review we will consider the mechanisms and manifestations of inadequate nutritional status in very young children with CKD, mechanisms mediating inadequate nutritional intake, and the optimal nutritional management of this special population. In addition, we suggest an approach to the assessment of nutritional status, including the use of body mass index in infants. Five major nutritional components are considered: energy, macronutrients, fluids and electrolytes, micronutrients, and calcium/phosphorus/vitamin D. The use of adjunctive therapies, including appetite stimulants, treatment of gastroesophageal reflux and gastric dysmotility, enhanced dialytic clearance, and growth hormone, is also briefly discussed.

Effects of Oral L-Carnitine Supplementation on Lipid Profile, Anemia, and Quality of Life in Chronic Renal Disease Patients under Hemodialysis: A Randomized, Double-Blinded, Placebo-Controlled Trial

In patients on maintenance hemodialysis several factors reduce the body stored carnitine which could lead to dyslipidemia, anemia, and general health in these patients. We evaluated the effect of oral L-carnitine supplementation on lipid profiles, anemia, and quality of life (QOL) in hemodialysis patients. In a randomized, double-blinded, placebo-controlled trial, end-stage renal disease (ESRD) patients on hemodialysis received either L-carnitine 1 g/d (n = 24) or placebo (27 patients) for 16 weeks. At the end of the study, there was a significant decrease in triglyceride (-31.1 ± 38.7 mg/dL, P = 0.001) and a significant increase in HDL (3.7 ± 2.8 mg/dL, P < 0.001) levels in the carnitine group. Decrease in total cholesterol (-6.6 ± 16.0 mg/dL, P = 0.075) and increase in hemoglobin (0.7 ± 1.7 g/dL, P = 0.081) concentrations in the carnitine group were not significant. There was no statistically significant changes in LDL in any group (P > 0.05). Erythropoietin dose was significantly decreased in both the carnitine (-4750 ± 5772 mg, P = 0.001) and the placebo group (-2000 ± 4296 mg, P < 0.05). No improvement was observed in QOL scores of two groups. In ESRD patients under maintenance hemodialysis, oral L-carnitine supplementation may reduce triglyceride and cholesterol and increase HDL and hemoglobin and subsequently reduce needed erythropoietin dose without effect on QOL.

Moving the issue of renal dietitian staffing forward

The day-to-day pragmatic work realities of dietitians who cover dialysis clinics are rarely the focus of discussion. This article highlights the points of convergence between these realities and the research literature. Focusing on the National Kidney Foundation Kidney Disease Outcomes Quality Initiative clinical practice guidelines for nutrition and the difficulties encountered with their full implementation, a seemingly pervasive problem of limited time is revealed. Given the evidence that renal dietitians can positively impact morbidity and mortality risks, when protein-energy malnutrition is primarily the byproduct of insufficient nutrient intake, it suggests that progress with enhancing the nutritional status of patients may be fundamentally contingent on increasing the time they have available, through improved staffing.

Nutrition in patients on peritoneal dialysis

Protein-energy wasting (PEW) is prevalent among patients on dialysis and has emerged as an important risk factor for morbidity and mortality in these patients. Numerous factors, including inflammation, inadequate dialysis, insufficient nutrient intake, loss of protein during dialysis, chronic acidosis, hypercatabolic illness and comorbid conditions, are involved in the development of PEW. The causes and clinical features of PEW in patients on peritoneal dialysis and hemodialysis are comparable; assessment of the factors that lead to PEW in patients receiving peritoneal dialysis is important to ensure that PEW is managed correctly in these patients. For the past 20 years, much progress has been made in the prevention and treatment of PEW. However, the results of most nutritional intervention studies are inconclusive. In addition, the multifactorial and complicated pathogenesis of PEW makes it difficult to assess and treat. This Review summarizes the nutritional issues regarding the causes, assessment and treatment of PEW, with a focus on patients receiving peritoneal dialysis. In addition, an in-depth overview of the results of nutritional intervention studies is provided.

Marked reductions in bioactive insulin-like growth factor I (IGF-I) during hemodialysis

OBJECTIVE

Hemodialysis (HD) patients lose lean body mass, even when they are adequately dialysed. One reason may be a decreased activity of the IGF-system. However, data on changes in bioactive IGF-I during HD are sparse.

DESIGN

Ten stable, non-diabetic HD patients were studied with 30 min intervals during a scheduled HD, with blood sampling before (-15 and 0 min), during (4 h) and after (1 h) the session. Patients were fasted for at least 6 h before and during the study. Arterial and venous blood was sampled for determination of IGF-I bioactivity, free and total IGF-I and IGF-II, IGF binding protein-1 (IGFBP-1), IGFBP-1 complexed IGF-I and IGFBP-2.

RESULTS

Total IGF-I and -II decreased marginally (<12%) at the very end of the study (P<0.05). By contrast, at 3 h free and bioactive IGF-I had declined by approximately 35% and 50%, respectively, and levels remained suppressed for the rest of the study (P<0.05). Concomitantly, IGFBP-1 and IGFBP-1:IGF-I complex formation increased 5.0-fold and 2.6-fold, respectively (P<0.05). By contrast, IGFBP-2 did not increase as a result of HD. No major differences between arterial and venous concentrations were observed.

CONCLUSION

Despite marginal reductions in total IGF-I and -II, bioactive and free IGF-I declined markedly during and after HD. This is likely a consequence of the increase in IGFBP-1, sequestering free IGF-I, and reducing bioactive IGF-I. Based on the present data we hypothesize that the catabolism induced by HD is in part related to the observed reductions in bioactive IGF-I.

[Assessment and follow-up of nutritional status in hemodialysis patients]

Malnutrition is common among hemodialysis patients and is associated with increased risk of morbidity and mortality. Early recognition and treatment of malnutrition is essential to improve the outcome of these patients. Nutritional status may be assessed by several clinical markers including dietary records, anthropometric measurements and subjective global assessment. Among biochemical parameters, albumin is the most commonly used and prealbumin the most useful. Protein catabolic rate reflects dietary protein intake. Body composition analysis by bioelectrical impedance analysis or better by dual energy X-ray absorptiometry offers a reasonable estimation of body compartments such as total body water, fat mass and lean body mass. Periodic assessment of nutritional status must take into account the limitations of each criteria used.

Population pharmacokinetic model for human growth hormone in adult patients in chronic dialysis compared with healthy subjects

OBJECTIVE

To develop a population pharmacokinetic (PK) model of recombinant human growth hormone (rhGH) treatment in patients with end-stage renal disease (ESRD) and healthy volunteers (HVs), to support future study design.

DESIGN

This was an open, non-randomized, single-centre parallel-group study lasting 8-9 days. Various compartment models with first-order and Michaëlis-Menten absorption and elimination were explored. Eleven adult ESRD patients and 10 matched HVs received 50 microg/kg/day rhGH (subcutaneous (s.c.) injection) for 8 or 7 days, respectively. Blood samples were drawn every 30 min for 24h following dosing on Days 0, 7 and 8 (ESRD patients). Influence of the covariates subject group (ESRD/HV), gender, weight, and dialysis flow-rate on model parameters was examined.

RESULTS

The final model was one-compartmental with Michaëlis-Menten absorption and elimination. The following estimates were obtained: maximum absorption rate (VMA) - 11.3 microg/kg/h (both groups); amount of drug corresponding to half-maximum absorption rate (KMA) - 1.06 and 18.8 microg/kg (ESRD patients and HVs, respectively; P<0.001); maximum elimination rate (VM) - 9.37 and 13.0 microg/kg/h (ESRD patients and HVs, respectively; P<0.001); amount of drug corresponding to half-maximum elimination rate - 18.9 microg/kg (both groups). Significant differences in KMA and VM between HVs and ESRD patients corresponded to higher absorption and lower elimination rates in ESRD, but all GH profiles were back to baseline by 20-22h and no overall accumulation occurred. Simplified posterior predictive checks indicated that the model satisfactorily captured PK. All non-compartmental estimates for AUC(0-24h) and C(max) lay within 95% confidence limits of the simulated distributions.

CONCLUSIONS

A population PK model was established, which showed acceptable performance for trial-simulation purposes.

Malnutrition and wasting in renal disease

PURPOSE OF REVIEW

Malnutrition and accelerated catabolism frequently complicate chronic kidney disease and end-stage renal disease. This review provides an update on the recent advances in the understanding of the mechanisms underlying protein-energy wasting, both in experimental and human models, and on the currently available therapeutic approaches.

RECENT FINDINGS

Increased levels of circulating cytokines, metabolic acidosis, oxidative stress and insulin resistance all appear to be variably implicated in muscle protein breakdown during end-stage renal disease and dialysis. The individual role of each component in the pathogenesis of chronic kidney disease-related wasting is still unclear, but recent clinical data show a positive relationship between inflammation and muscle protein catabolism as a major contributing factor.

SUMMARY

The basis for appropriate therapeutic approaches to protein-energy wasting in chronic kidney disease and end-stage renal disease relies entirely on the understanding of its pathophysiology. Our knowledge of the pathogenesis of malnutrition and hypercatabolism in renal disease is still limited and mostly based on experimental data, but the currently available evidence suggests that multimodal preventive and therapeutic strategies should be entertained.

Serial monitoring of nutritional status in Chinese peritoneal dialysis patients by Subjective Global Assessment and comprehensive Malnutrition Inflammation Score

AIM

The Malnutrition Inflammation Score (MIS) has been proposed for the assessment of nutritional status in peritoneal dialysis (PD) patients. The MIS and the Subjective Global Assessment (SGA) for serial monitoring of nutritional status in PD patients were compared.

METHODS

The change in the MIS and SGA overall score of 59 PD patients (28 male) over 12 months was studied. Clinical factors relating to the discrepancy between the two instruments were explored.

RESULTS

The average patient age was 55.8+/-9.7 years. Thirty of the 59 patients (50.8%) had exact agreement in the changed MIS and SGA scores. Cohen's kappa score was 0.274, indicating a modest degree of agreement. For the detection of deterioration in nutritional status and using the MIS as the reference measure, the SGA had a sensitivity of 61.9% and specificity of 86.8%; serum ferritin level was substantially higher in the ones whose SGA did not detect a deterioration in nutrition (1464.1+/-873.3 vs 800.5+/-561.6 pmol/L, P=0.046). For the detection of improvement in nutritional status, the SGA had a sensitivity of 45.8% and specificity of 82.9%; patients whose SGA did not detect an improvement in nutrition were dialyzed longer (53.8+/-35.3 vs 27.6+/-18.9 months, P=0.038), had higher total iron binding capacity (TIBC) (45.6+/-5.5 vs 38.2+/-8.1 micromol/L, P=0.015), had higher total Kt/V (2.02+/-0.36 vs 1.75+/-0.23, P=0.048) and higher normalized protein nitrogen appearance (1.16+/-0.25 vs 0.95+/-0.23 g/kg per day, P=0.048).

CONCLUSION

The longitudinal changes in the MIS and SGA score have modest agreement with each other. However, PD patients with a longer duration of dialysis, higher serum ferritin, TIBC, total Kt/V or normalized protein nitrogen appearance tend to have discrepancies between the longitudinal changes in the MIS and SGA overall score.

Nutrition aspects in children receiving maintenance hemodialysis: impact on outcome

Children with end-stage renal disease (ESRD) have rates of mortality estimated to be 30-times higher than expected for age compared with those of healthy children. Physical manifestations of under-nutrition, such as body mass index (BMI) and low height standard deviation score (SDS), have been associated with increased risk of mortality. Traditional measures, such as height, weight and serum albumin concentration, may not be accurate indicators to assess the nutritional status of children receiving maintenance hemodialysis. Normalized protein catabolic rate (nPCR) has emerged as a better marker of nutritional status of such children. Meeting the special nutritional needs of these children often requires nutritional supplementation, by either the enteral or the parenteral route. Recently, in children receiving maintenance hemodialysis who are malnourished, intradialytic parenteral nutrition (IDPN) has been utilized as a means to provide additional protein and calories. This article is a state-of-the-art review of malnutrition in children receiving maintenance hemodialysis, with special focus on outcome, nPCR and IDPN.

Nutritional status and the role of diabetes mellitus in hemodialysis patients

This study was aimed to investigate the nutritional status and the role of diabetes mellitus in hemodialysis (HD) patients. Anthropometric, biochemical, and dietary assessments for HD 110 patients (46 males and 64 females) were conducted. Mean body mass index (BMI) was 22.1 kg/m(2) and prevalence of underweight (BMI<18.5 kg/m(2)) was 12%. The hypoalbuminemia (<3.5 g/dl) was found in 15.5% of the subject, and hypocholesterolemia (<150 mg/dl) in 46.4%. About half (50.9%) patients had anemia (hemoglobin: <11.0 g/dL). High prevalence of hyperphosphatemia (66.4%) and hyperkalemia (43.5%) was also observed. More than 60 percent of subjects were below the recommended intake levels of energy (30-35 kcal/kg IBW) and protein (1.2 g/kg IBW). The proportions of subjects taking less than estimated average requirements for calcium, vitamin B(1), vitamin B(2), vitamin C, and folate were more than 50%, whereas, about 20% of the subjects were above the recommended intake of phosphorus and potassium. Diabetes mellitus was the main cause of ESRD (45.5%). The diabetic ESRD patients showed higher BMI and less HD adequacy than nondiabetic patients. Diabetic patients also showed lower HDL-cholesterol levels. Diabetic ESRD patients had less energy from fat and a greater percentage of calories from carbohydrates. In conclusion, active nutrition monitoring is needed to improve the nutritional status of HD patients. A follow-up study is needed to document a causal relation between diabetes and its impact on morbidity and mortality in ESRD patients.