Dietary Quality and Adherence to Dietary Recommendations in Patients Undergoing Hemodialysis

"I have to pick my battles": a mixed-methods study exploring food insecurity and dietary restrictions in pediatric kidney disease

BACKGROUND

Food insecurity (FI) is prevalent among children with chronic kidney disease (CKD), but its impact on health outcomes, and feasibility of prescribed diet restrictions is unknown. Accordingly, this study aims to explore associations of FI and CKD outcomes, and understand its role in following prescribed kidney diet recommendations.

METHODS

We performed a mixed-methods single-center cohort study of children with advanced CKD or kidney failure. Demographics, socioeconomic status, and health outcomes were compared across FI status; associations between FI and CKD outcomes were explored using multivariable regression. A qualitative sub-analysis of de-identified caregiver interview transcripts was analyzed for themes around diet restrictions.

RESULTS

There was a trend that FI patients were more likely to be of Black race (33% vs. 20%); have public insurance (67% vs. 48%); need more blood pressure medications (2 [0.75,3] vs. 1 [0,3]); and have a higher likelihood of emergency department (42% vs. 25%) or intensive care unit encounters (25% vs. 14%). There were no associations of FI and outcomes of interest. Major themes that emerged from caregiver interviews include (1) understanding of the kidney diet focuses on foods to avoid; (2) adapting to suggested dietary restrictions requires changes in meal preparation; and (3) challenges to adherence include social stigma, growth, budget, and time.

CONCLUSIONS

The impact of FI on children's medical needs with CKD remains inconclusive but trends suggest a higher risk. Regardless of FI status, adhering to prescribed diet restrictions in kidney disease involves significant dedication. Challenges involve food availability, a child's response to restrictions, and social stigma.

Feeling gutted in chronic kidney disease (CKD): Gastrointestinal disorders and therapies to improve gastrointestinal health in individuals CKD, including those undergoing dialysis

Chronic kidney disease (CKD) affects 9.1% of the population worldwide. CKD may lead to structural and functional gastrointestinal alterations, including impairment in the intestinal barrier, digestion and absorption of nutrients, motility, and changes to the gut microbiome. These changes can lead to increased gastrointestinal symptoms in people with CKD, even in early grades of kidney dysfunction. Gastrointestinal symptoms have been associated with lower quality of life and reduced nutritional status. Therefore, there has been considerable interest in improving gastrointestinal health in this clinical population. Gastrointestinal health can be influenced by lifestyle and medications, particularly in advanced grades of kidney dysfunction. Therapies focused on gastrointestinal health have been studied, including the use of probiotics, prebiotics, and synbiotics, yielding limited and conflicting results. This review summarizes the alterations in the gastrointestinal tract structure and function and provides an overview of potential nutritional interventions that kidney disease professionals can provide to improve gastrointestinal health in individuals with CKD.

Dieta de la Milpa: A Culturally-Concordant Plant-Based Dietary Pattern for Hispanic/Latine People with Chronic Kidney Disease

Chronic kidney disease (CKD) disproportionately affects minorities in the United States, including the Hispanic/Latine population, and is a public health concern in Latin American countries. An emphasis on healthy dietary patterns, including the Mediterranean and the Dietary Approaches to Stop Hypertension (DASH) diets, has been suggested as they are associated with a lower incidence of CKD, slower CKD progression, and lower mortality in kidney failure. However, their applicability may be limited in people from Latin America. The Dieta de la Milpa (Diet of the Cornfield) was recently described as the dietary pattern of choice for people from Mesoamerica (Central Mexico and Central America). This dietary pattern highlights the intake of four plant-based staple foods from this geographical region, corn/maize, common beans, pumpkins/squashes, and chilies, complemented with seasonal and local intake of plant-based foods and a lower intake of animal-based foods, collectively classified into ten food groups. Limited preclinical and clinical studies suggest several health benefits, including cardiometabolic health, but there is currently no data concerning CKD. In this narrative review, we describe and highlight the potential benefits of the Dieta de la Milpa in CKD, including acid-base balance, protein source, potassium and phosphorus management, impact on the gut microbiota, inflammation, and cultural appropriateness. Despite these potential benefits, this dietary pattern has not been tested in people with CKD. Therefore, we suggest key research questions targeting measurement of adherence, feasibility, and effectiveness of the Dieta de la Milpa in people with CKD.

Muscle Strength and Biochemical Markers as Predictors of Depression in Hemodialysis Patients: A Cross-Sectional Study

Patients with chronic renal failure, many of which treated with hemodialysis, present a high prevalence of impaired muscle strength which suggest that muscle mass parameters may be used as markers for changes in muscle in these patients. Measurement of handgrip strength (HGS) is a common, simple, and quick measure of muscle function an indicator of overall muscle strength which has been associated with physical activity and several anthropometric traits. Intercellular adhesion molecule-1 (ICAM-1) and insulin-like growth factor-1 (IGF-1) are biochemical markers associated with inflammatory processes which are a common consequence of dialysis. Additionally, hemodialysis patients frequently present signs of malnutrition and depression. This cross-sectional study aimed to evaluate if muscle and biochemical markers could be used to predict the risk of depression in hemodialysis patients. Several anthropometric parameters, nutrient intake, depression state and the serum levels of ICAM-1 and IGF-1 were determined and Pearson's correlation coefficient and/or Spearman's correlation coefficient were used to test the correlation between them. Our results do not show a correlation between HGF, IGF-1 and ICAM-1 with the depression status of the patients, but mid-arm muscle circumference (MAMC) was statistically and positively correlated with depression. Additionally, ICAM-1 levels were negatively correlated with HGS, MAMC, and IGF-1. Overall, the results of the present study suggest that HGS may be used as an indicator of cardiovascular diseases and MAMC may be a good predictor of the level of depression in hemodialysis patients, although further studies are required.

Dietary Intake Correlated to Waist-To-Hip Ratio in Patients on Maintenance Hemodialysis

OBJECTIVE

Individuals with end-stage kidney disease (ESKD) receiving maintenance hemodialysis (MHD) are at risk for protein-energy wasting (PEW). Inadequate dietary intake and altered anthropometrics are two criteria of the PEW diagnosis. This study explored whether individuals with ESKD on MHD meet the National Kidney Foundation Kidney Disease Outcome Quality Initiative (NKF-KDOQI) 2020 guidelines for nutritional adequacy on a dialysis treatment day (DD) and explored the relationship between dietary energy [DEI] and protein [DPI] intake and anthropometrics.

METHODS

This was a secondary analysis of clinical and demographic data for 142 adults from the Rutgers Nutrition and Kidney Disease database. The study assessed the relationships between DEI, DPI, and anthropometrics, including body mass index (BMI), BMI category, waist circumference, and waist-to-hip ratio (WHR) using Pearson's or Spearman's correlation and one-way ANOVA.

RESULTS

The sample had a median age of 55.7 years; 58% were male, 83.8% were Black/African American, with a median dialysis vintage of 42.0 months (e.g., 3.5 years). Seventy-five percent of the data sample were overweight or obese. The WHR was 1.0 ± 0.8 cm for males and 0.9 ± 0.1 for females. DEI and DPI on a DD did not meet the NKF-KDOQI 2020 guidelines. Median DEI was 17.6 ± 8.4 kcal/kg and DPI was 0.7 ± 0.4 g/kg. In the total sample, significant positive correlations were found between DEI (r = 0.74, P = 0.03) and DPI (r = 0.18, P = 0.037) and WHR. In females, a significant positive correlation was identified between DPI and WHR (r = 0.26, P = 0.046).

CONCLUSIONS

These findings suggest that the nutritional intake of individuals with ESKD receiving MHD is inadequate to meet NKF-KDOQI 2020 guidelines on a DD. WHR may be a useful tool to assess alterations in anthropometrics related to DEI or DPI in this population, but more research is warranted.

Magnesium and Fracture Risk in the General Population and Patients Receiving Dialysis: A Narrative Review

Purpose of Review

Magnesium is an essential mineral for bone metabolism, but little is known about how magnesium intake alters fracture risk. We conducted a narrative review to better understand how magnesium intake, through supplementation, diet, or altering the concentration of dialysate magnesium, affects mineral bone disease and the risk of fracture in individuals across the spectrum of kidney disease.

Sources of Information

Peer-reviewed clinical trials and observational studies.

Methods

We searched for relevant articles in MEDLINE and EMBASE databases. The methodologic quality of clinical trials was assessed using a modified version of the Downs and Black criteria checklist.

Key Findings

The role of magnesium intake in fracture prevention is unclear in both the general population and in patients receiving maintenance dialysis. In those with normal kidney function, 2 meta-analyses showed higher bone mineral density in those with higher dietary magnesium, whereas 1 systematic review showed no effect on fracture risk. In patients receiving maintenance hemodialysis or peritoneal dialysis, a higher concentration of dialysate magnesium is associated with a lower concentration of parathyroid hormone, but little is known about other bone-related outcomes. In 2 observational studies of patients receiving hemodialysis, a higher concentration of serum magnesium was associated with a lower risk of hip fracture.

Limitations

This narrative review included only articles written in English. Observed effects of magnesium intake in the general population may not be applicable to those with chronic kidney disease particularly in those receiving dialysis.

Activity and Profile of the Users of a Novel Mobile Application Supporting Proper Diet Among Maintenance Hemodialysis Patients

OBJECTIVE

Diet plays a key role in the management of chronic kidney disease. The aim of our study was to evaluate the usage of a self-developed mobile application supporting proper dietary choices among maintenance hemodialysis (HD) patients.

METHODS

The primary functions of the application are to provide databases of products and recipes. Data on user activity recorded using Internet solutions were collected for 12 months from April 2021. The application was promoted both via the Internet and directly to patients. Additionally, a questionnaire was employed to evaluate the usage of the software.

RESULTS

The application was downloaded by 841 smartphone users, 44.4% of whom were from 2 regions of Poland with the largest populations of HD patients. Residents of cities with a population above 250,000 accounted for 86.0% of users. Sixty HD patients (32 males, 28 females; age 56.2 ± 14.8 years) filled the questionnaire. All features of the application scored a median of 4.0 points or higher on a 5-point Likert scale; however, 63.3% of respondents indicated the need to improve particular functions of the application. There was a significant difference in dialysis vintage between respondents who used the application for less than 1 month and others (1.0 vs. 3.3 years; P = .02). The positive perception of its influence on diet adherence was significantly higher among younger (<50 years) compared to older users (5.0 vs. 4.0; P = .03) and among women compared to men (5.0 vs. 4.0; P = .01).

CONCLUSION

HD patients showed interest in dietary mobile applications, and Internet channels were effective in promoting the software. Place of residency, age, gender, and dialysis vintage are factors that influence patient satisfaction with and the time of using the mobile application.

Dietary protection against the visual and motor deficits induced by experimental autoimmune encephalomyelitis

Introduction

Five to eight percent of the world population currently suffers from at least one autoimmune disorder. Despite multiple immune modulatory therapies for autoimmune demyelinating diseases of the central nervous system, these treatments can be limiting for subsets of patients due to adverse effects and expense. To circumvent these barriers, we investigated a nutritional intervention in mice undergoing experimental autoimmune encephalomyelitis (EAE), a model of autoimmune-mediated demyelination that induces visual and motor pathologies similar to those experienced by people with multiple sclerosis (MS).

Methods

EAE was induced in female and male mice and the impact of limiting dietary carbohydrates by feeding a ketogenic diet (KD) enriched in medium chain triglycerides (MCTs), alpha-linolenic acid (an omega-3 fatty acid), and fiber was evaluated in both a preventive regimen (prior to immunization with MOG antigen) and an interventional regimen (following the onset of symptoms). Motor scores were assigned daily and visual acuity was measured using optokinetic tracking. Immunohistochemical analyses of optic nerves were done to assess inflammatory infiltrates and myelination status. Fatty acid and cytokine profiling from blood were performed to evaluate systemic inflammatory status.

Results

The KD was efficacious when fed as a preventive regimen as well as when initiated as an interventional regimen following symptom onset. The KD minimally impacted body weight during the experimental time course, increased circulating ketones, prevented motor and ocular deficits, preserved myelination of the optic nerve, and reduced infiltration of immune cells to optic nerves. The KD also increased anti-inflammatory-associated omega-3 fatty acids in the plasma and reduced select cytokines in the circulation associated with EAE-mediated pathological inflammation.

Discussion

In light of ongoing clinical trials using dietary strategies to treat people with MS, these findings support that a KD enriched in MCTs, omega-3 fatty acids, and fiber promotes a systemic anti-inflammatory milieu and ameliorates autoimmune-induced demyelinating visual and motor deficits.

Nutritional and Hydration Status and Adherence to Dietary Recommendations in Dalmatian Dialysis Patients

Protein-energy wasting (PEW) is considered one of the major complications of chronic kidney disease (CKD), particularly in dialysis patients. Insufficient energy and protein intake, together with clinical complications, may contribute to the onset and severity of PEW. Therefore, the aim of the study was to analyze the differences in nutritional and hydration status and dietary intake among Dalmatian dialysis patients. Fifty-five hemodialysis (HD) and twenty peritoneal dialysis (PD) participants were included. For each study participant, data about body composition, anthropometric, laboratory, and clinical parameters were obtained. The Malnutrition Inflammation Score (MIS) and two separate 24-h dietary recalls were used to assess nutritional status and dietary intake. The Nutrient Adequacy Ratio (NAR) and Mean Adequacy Ratio (MAR) were calculated to compare actual dietary intake with recommended intake. Additionally, the estimated 10-year survival was calculated using the Charlson Comorbidity Index. The prevalence of malnutrition according to MIS was 47.3% in HD and 45% in PD participants. Significant differences in fat tissue parameters were found between HD and PD participants, whereas significant differences in hydration status and muscle mass parameters were not found. A significant difference in NAR between HD and PD participants was noticed for potassium and phosphorus intake, but not for MAR. MIS correlated negatively with anthropometric parameters, fat mass, visceral fat level and trunk fat mass, and iron and uric acid in HD participants, whereas no significant correlations were found in PD participants. The estimated 10-year survival correlated with several parameters of nutritional status in HD and PD participants, as well as nutrient intake in HD participants. These results indicate a high prevalence of malnutrition and inadequate dietary intake in the Dalmatian dialysis population which, furthermore, highlights the urgent need for individualized and structural nutritional support.

Protein/Fiber Index Modulates Uremic Toxin Concentrations in Hemodialysis Patients

Background: Indoxyl sulfate (IS) and p-cresyl sulfate (PCS), two uremic toxins (UTs), are associated with increased mortality in patients with chronic kidney disease (CKD). These toxins are produced by the microbiota from the diet and excreted by the kidney. The purpose of this study was to analyze the effect of diet on IS and PCS concentration in hemodialysis (HD) patients. Methods: We performed a prospective monocentric study using a seven-day diet record and determination of serum IS and PCS levels in HD patients. We tested the association between toxin concentrations and nutritional data. Results: A total of 58/75 patients (77%) completed the diet record. Mean caloric intake was 22 ± 9.2 kcal/kg/day. The protein/fiber index was 4.9 ± 1.8. No correlation between IS or PCS concentration and protein/fiber index was highlighted. In the 18 anuric patients (31%) in whom residual renal function could not affect toxin concentrations, IS and PCS concentrations were negatively correlated with fiber intake and positively correlated with the protein/fiber index. In a multivariate analysis, IS serum concentration was positively associated with the protein/fiber index (p = 0.03). Conclusions: A low protein/fiber index is associated with low concentrations of uremic toxins in anuric HD patients. Diets with an increased fiber intake must be tested to determine whether they reduce PCS and IS serum concentrations.

The "FIFTY SHADOWS" of the RALES Trial: Lessons about the Potential Risk of Dietary Potassium Supplementation in Patients with Chronic Kidney Disease

Hyperkalaemia (HK) is one of the most common electrolyte disorders and a frequent reason for nephrological consultations. High serum potassium (K+) levels are associated with elevated morbidity and mortality, mainly due to life-threatening arrhythmias. In the majority of cases, HK is associated with chronic kidney disease (CKD), or with the use of renin-angiotensin-aldosterone system inhibitors (RAASis) and/or mineral corticoid antagonists (MRAs). These drugs represent the mainstays of treatment in CKD, HF, diabetes, hypertension, and even glomerular diseases, in consideration of their beneficial effect on hard outcomes related to cardiovascular events and CKD progression. However, experiences in relation to the Randomised Aldactone Evaluation Study (RALES) cast a long shadow that extends to the present day, since the increased risk for HK remains a major concern. In this article, we summarise the physiology of K+ homeostasis, and we review the effects of dietary K+ on blood pressure and cardiovascular risk in the general population and in patients with early CKD, who are often not aware of this disease. We conclude with a note of caution regarding the recent publication of the SSaSS trial and the use of salt substitutes, particularly in patients with a limited capacity to increase K+ secretion in response to an exogenous load, particularly in the context of "occult" CKD, HF, and in patients taking RAASis and/or MRAs.

Correlations among lean tissue index, physical activity, clinical parameters, diet quality, and nutritional status in patients receiving haemodialyses

INTRODUCTION

Poor diet quality and malnutrition accelerate protein and energy depletion. This can result in a diminished lean tissue index (LTI) and an inability to perform daily activities, both of which increase the risk of falls and affect the quality of life.

OBJECTIVE

This study investigated the correlations among LTI, physical activity (PA), clinical parameters, diet quality, and nutritional status.

METHODS

A cross-sectional study design was employed. Participants in stable conditions receiving haemodialyses were enroled. LTI was measured using a body composition monitor. Three-day dietary records and demographic and clinical parameters were collected.

RESULTS

In total, 104 patients receiving haemodialyses were recruited (53.8% men, aged 57.7 ± 11.78 years; dialysis duration, 7.3 ± 6.04 years). LTI was not associated with diet quality; LTI was positively correlated with sex and negatively correlated with age, dialysis duration, and fat tissue index (FTI); and lean tissue index was positively correlated with PA. Among patients with a normal LTI, the odds ratio for low-FTI was 31.04 times higher than that for high-FTI. In total, 80.8% of the participants had poor diet quality, which was mainly attributed to their excessive intake of saturated fatty acids and insufficient fruit intake.

CONCLUSIONS

Although diet quality was unrelated to the LTI, the results indicated that most patients receiving haemodialyses had poor diet quality. Therefore, this topic merits further investigation.

Liposoluble vitamins A and E in kidney disease

Kidney disease (KD) is characterized by the presence of elevated oxidative stress, and this is postulated as contributing to the high cardiovascular morbidity and mortality in these individuals. Chronic KD (CKD) is related to high grade inflammatory condition and pro-oxidative state that aggravates the progression of the disease by damaging primary podocytes. Liposoluble vitamins (vitamin A and E) are potent dietary antioxidants that have also anti-inflammatory and antiapoptotic functions. Vitamin deficits in CKD patients are a common issue, and multiple causes are related to them: Anorexia, dietary restrictions, food cooking methods, dialysis losses, gastrointestinal malabsorption, etc. The potential benefit of retinoic acid (RA) and α-tocopherol have been described in animal models and in some human clinical trials. This review provides an overview of RA and α tocopherol in KD.

Potential Benefits of Pila ampullacea, Tempeh, Moringa oleifera Leaves as Nutritional Support for Hemodialysis

Background:

Hemodialysis patients can experience problems, including protein-energy malnutrition, infection, disorders of the immune system, and inflammation. One etiology of malnutrition in hemodialysis is inadequate energy and protein intake, making patients need nutritional support, which can be fulfilled by local Indonesian foodstuffs.

Objective:

This paper aimed to review the potential health benefits of snails (Pila ampullacea), tempeh, and Moringa oleifera leaves as nutritional support for hemodialysis patients.

Methods:

In this review, the methodology used was based on comprehensive data searched from PubMed for literature review and technology benchmarking in making nutritional support for hemodialysis patients. An in-depth discussion, including the advantages and drawbacks of each foodstuff, is presented and outlined. Furthermore, key solutions are proposed and presented to overcome hemodialysis issues.

Results:

The mixture of snail, tempeh, and moringa leaves as nutritional support for hemodialysis patients shows a good combination of natural ingredients from animals and plants. The nutritional content of the three mixed ingredients is found to meet the dietary requirements of hemodialysis, which are high protein, calcium and antioxidants, low phosphorus, and a phosphorus-to-protein ratio of <16.

Conclusion:

The combination of snails, tempeh, and moringa leaves provides several potential health benefits in overcoming nutritional problems, decreased immune status, and inflammation of hemodialysis patients.

Benchmarking Diet Quality to Assess Nutritional Risk in Hemodialysis Patients: Applying Adequacy and Moderation Metrics of the Hemodialysis-Healthy Eating Index

OBJECTIVES

This study modified Healthy Eating Index (HEI) based on hemodialysis (HD) specific guidelines and investigated associations between the diet quality (DQ) and nutritional risk in HD patients.

METHODS

The HD-HEI tool adapted the XXX Dietary Guidelines 2010 framework according to HD-specific nutrition guidelines. This HD-HEI was applied to 3-day dietary records of 382 HD patients. Relationships between HD-HEI scores and nutritional parameters were tested by partial correlations. Binary logistic regression models adjusted with confounders were used to determine adjusted odds ratio (_adjOR) with 95% confidence interval (CI) for nutritional risk based on HD-HEI scores categorization.

RESULTS

The total HD-HEI score (51.3 ± 10.2) for this study population was affected by ethnicity (P_trend<0.001) and sex (P=0.003). No patient achieved "good" DQ (score: 81-100), while DQ of 54.5% patients were classified as "needs improvement" (score: 51-80) and remaining as "poor" (score: 0-51). Total HD-HEI scores were positively associated with dietary energy intake (DEI) and dietary protein intakes (DPI), dry weight and handgrip strength, but inversely associated with Dietary Monotony Index (DMI) (all P<0.05). Individually, scores for refined grain, total protein, and animal protein were positively associated with DEI (all P< 0.05), whilst total, animal, fish and vegetable proteins indicated positive associations with DPI (all P< 0.05). Moderating metrics for convenience meals, saturated fats, sodium, and fluid negatively correlated towards DEI with similar trends for DPI excepting convenience meals and fluids. "Poor" DQ was associated with DMI ≥ 29.2 (_adjOR: 18.83, 95% CI: 9.36-37.86, P<0.001), Malnutrition Inflammation Score (MIS) ≥ 5 (_adjOR: 1.78, 95% CI: 1.01-3.15, P=0.045), and Protein Energy Wasting (PEW) (_adjOR: 1.96, 95% CI: 1.14-3.34, P=0.031), but became nullified with covariate adjustments. "Poor" DQ was also associated with low lean tissue mass (< 32.6 kg) in men (_adjOR: 2.38, 95% CI: 1.01-5.58, P=0.046) but not women.

CONCLUSIONS

"Poor" DQ was associated with poor nutritional status in XXX HD patients, who should be targeted for nutritional counselling.

Nutrition, Immunology, and Kidney: Looking Beyond the Horizons

PURPOSE OF REVIEW

Chronic kidney disease (CKD) is epidemic throughout the word. Despite various novel therapeutic opportunities, CKD is still associated with high morbidity and mortality. In CKD, patient's chronic inflammation is frequent and related with adverse outcomes. Both innate and adaptive immunity are dysfunctional in CKD. Therefore, it is plausible to interfere with dysfunctional immunity in these patients. In the current review, we present the updated experimental and clinical data summarizing the effects of nutritional interventions including natural products and dietary supplements on immune dysfunction in the context of CKD.

RECENT FINDINGS

Nutritional interventions including natural products and dietary supplements (e.g., curcumin, sulforaphane, resistant starch, anthocyanin, chrysin, short chain fatty acids, fish oil resistant starch) slow down the inflammation by at least 6 mechanisms: (i) decrease nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB); (ii) decrease NLR family pyrin domain containing 3 (NLRP3); (iii) decrease interleukin-1 (IL-1), decrease interleukin-6 (IL-6) secretion; (iv) decrease polymorphonuclear priming); (v) promote anti-inflammatory pathways (nuclear factor-erythroid factor 2-related factor 2 (NFR2); (vi) increase T regulatory (Tregs) cells). Natural products and dietary supplements may provide benefit in terms of kidney health. By modulation of nutritional intake, progression of CKD may be delayed.

Higher dietary fibre intake is associated with lower CVD mortality risk among maintenance haemodialysis patients: a multicentre prospective cohort study

High fibre intake is associated with reduced mortality risk in both general and chronic kidney disease populations. However, in dialysis patients, such data are limited. Therefore, the association between dietary fibre intake (DFI) and the risk of all-cause and CVD mortality was examined in this study. A total of 1044 maintenance haemodialysis (MHD) patients from eight outpatient dialysis centres in China were included in this study. Data on DFI were collected using 24-h dietary recalls for 3 d in a week and were normalised to actual dry weight. The study outcomes included all-cause and CVD mortality. Over a median of 46 months of follow-up, 354 deaths were recorded, of which 210 (59 %) were due to CVD. On assessing DFI as tertiles, the CVD mortality risk was significantly lower in patients in tertiles 2-3 (≥0·13 g/kg per d; hazard ratio (HR) 0·71; 95 % CI 0·51, 0·97) compared with those in tertile 1 (<0·13 g/kg per d). A similar but non-significant trend was found for the association between DFI (tertiles 2-3 v. tertile 1; HR 0·83; 95 % CI 0·64, 1·07) and all-cause mortality. In summary, higher DFI was associated with lower CVD mortality risk among Chinese MHD patients. This study emphasises the significance of DFI in MHD patients and provides information that is critical for the improvement of dietary guidelines for dialysis patients.

Magnesium intake by enteral formulation affects serum magnesium concentration in patients undergoing hemodialysis

Decreased serum magnesium levels are associated with mortality and fractures in patients with chronic kidney disease; however, there is no recommendation for Mg intake in these populations. This study used cross-sectional analysis to examine the association between Mg intake and serum Mg levels in patients undergoing hemodialysis. Sixty-one patients were included. The daily Mg intake was 185 mg (IQR: 151-203 mg), and serum Mg level was 2.4 mg/dL (IQR: 2.2-2.7 mg/dL). Multiple regression analysis showed that intake of enteral formulation by tube feeding was an independent factor associated with serum Mg level (B = 0.90 [95% confidence interval: 0.61-1.20], p < 0.01). These findings may aid in serum Mg level management through diet and enteral formulation in patients undergoing hemodialysis.

Low adherence to CKD-specific dietary recommendations associates with impaired kidney function, dyslipidemia, and inflammation

BACKGROUND/OBJECTIVES

A diet following chronic kidney disease (CKD)-specific recommendations is considered essential for optimal management of patients with CKD. However, data on the adherence to these recommendations and its implications for health-relevant biomarkers are lacking. The objectives were to estimate adherence to CKD-specific dietary recommendations, to identify characteristics and lifestyle variables associated with poor adherence, and to investigate the relationship of adherence with biomarkers.

METHODS

In this cross-sectional analysis, average dietary intake was estimated in 3193 participants with moderately severe CKD enrolled into the observational multicenter German CKD study using a food frequency questionnaire. A CKD diet score was developed to assess adherence to CKD-specific dietary recommendations based on intake of sodium, potassium, fiber, protein, sugar, and cholesterol. The associations of dietary adherence with characteristics, lifestyle variables, and biomarker levels were determined.

RESULTS

Logistic regression analysis revealed younger age, higher body mass index, male gender, lower educational attainment, various lifestyle variables (cigarette smoking, infrequent alcohol consumption, low physical activity), and lower estimated glomerular filtrate rate associated with lower adherence to dietary recommendations. Low adherence to dietary recommendations was further associated with dyslipidemia, higher uric acid, and C-reactive protein levels. Associations between low dietary adherence and biomarkers were mostly driven by low intake of fiber and potassium, and high intake of sugar and cholesterol.

CONCLUSIONS

This study revealed differential characteristics and biomarkers associated with lower adherence to CKD-specific dietary recommendations. Promotion of CKD-specific dietary recommendations may help to mitigate the adverse prognosis in CKD patients.

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

OBJECTIVE

The prebiotic fiber inulin has been studied in individuals undergoing hemodialysis (HD) due to its ability to reduce gut microbiota-derived uremic toxins. However, studies examining the effects of inulin on the gut microbiota and derived metabolites are limited in these patients. We aimed to assess the impact of a 4-week supplementation of inulin on the gut microbiota composition and microbial metabolites of patients on HD.

DESIGN AND METHODS

In a randomized, double-blind, placebo-controlled, crossover study, twelve HD patients (55 ± 10 y, 50% male, 58% Black American, BMI 31.6 ± 8.9 kg/m2, 33% diabetes mellitus) were randomized to consume inulin [10 g/d for females; 15 g/d for males] or maltodextrin [6 g/d for females; 9 g/d for males] for 4 weeks, with a 4-week washout period. We assessed the fecal microbiota composition, fecal metabolites (short-chain fatty acids (SCFA), phenols, and indoles), and plasma indoxyl sulfate and p-cresyl sulfate.

RESULTS

At baseline, factors that explained the gut microbiota variability included BMI category and type of phosphate binder prescribed. Inulin increased the relative abundance of the phylum Verrucomicrobia and its genus Akkermansia (P interaction = 0.045). Inulin and maltodextrin resulted in an increased relative abundance of the phylum Bacteroidetes and its genus Bacteroides (P time = 0.04 and 0.03, respectively). Both treatments increased the fecal acetate and propionate (P time = 0.032 and 0.027, respectively), and there was a trend toward increased fecal butyrate (P time = 0.06). Inulin did not reduce fecal p-cresol or indoles, or plasma concentrations of p-cresyl sulfate or indoxyl sulfate.

CONCLUSIONS

A 4-week supplementation of inulin did not lead to major shifts in the fecal microbiota and gut microbiota-derived metabolites. This may be due to high variability among participants and an unexpected increase in fecal excretion of SCFA with maltodextrin. Larger studies are needed to determine the effects of prebiotic fibers on the gut microbiota and clinical outcomes to justify their use in patients on HD.

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.

Nutritional status, hyperkalaemia and attainment of energy/protein intake targets in haemodialysis patients following plant-based diets: a longitudinal cohort study

Background

Patients undergoing haemodialysis (HD) are often discouraged from eating fruits and vegetables because of fears of hyperkalaemia and undernutrition, yet evidence to support these claims is scarce. We here explore the association between adherence to a healthy plant-based diet with serum potassium, surrogates of nutritional status and attainment of energy/protein intake targets in HD patients.

Methods

We performed an observational single-centre study of stable patients undergoing HD with repeated dietary assessment every 3 months. Patients were provided with personalized nutritional counselling according to current guidelines. The diet was evaluated by 3-day food records and characterized by a healthy plant-based diet score (HPDS), which scores positively the intake of plant foods and negatively animal foods and sugar. The malnutrition inflammation score (MIS) and serum potassium were also assessed at each visit. We used mixed-effects models to evaluate the association of the HPDS with markers of nutritional status, serum potassium levels and attainment of energy/protein intake targets.

Results

After applying inclusion and exclusion criteria, a total of 150 patients contributing to 470 trimestral observations were included. Their mean age was 42 years [standard deviation (SD) 18] and 59% were women. In multivariable models, a higher HPDS was not associated with serum potassium levels or odds of hyperkalaemia {potassium >5.5 mEq/L; odds ratio [OR] 1.00 [95% confidence interval (CI) 0.94–1.07] per HPDS unit higher}. Patients with a higher HPDS did not differ in terms of energy intake [OR for consuming <30 kcal/kg day 1.05 (95% CI 0.97–1.13)] but were at risk of low protein intake [OR for consuming <1.1 g of protein/kg/day 1.11 (95% CI 1.04–1.19)]. A higher HPDS was associated with a lower MIS, indicating better nutritional status.

Conclusions

In patients undergoing HD, adherence to a healthy plant-based diet was not associated with serum potassium, hyperkalaemia or differences in energy intake. Although these patients were less likely to reach daily protein intake targets, they appeared to associate with better nutritional status over time.

Assessment of Factors Related to Diminished Appetite in Hemodialysis Patients with a New Adapted and Validated Questionnaire

Appetite loss is a common phenomenon in end-stage renal disease (ESRD) patients undergoing maintenance hemodialysis (HD). We aimed to (i) adapt and validate a Spanish language version of the Council on Nutrition Appetite Questionnaire (CNAQ) and (ii) to identify psychological and biological factors associated with diminished appetite. We recruited 242 patients undergoing HD from four hemodialysis centers to validate the Spanish-translated version of the CNAQ. In another set of 182 patients from three HD centers, the Appetite and Diet Assessment Tool (ADAT) was used as the gold standard to identify a cut-off value for diminished appetite in our adapted questionnaire. The Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), Distorted Thoughts Scale (DTS), Dialysis Malnutrition Score (DMS), anthropometric, values and laboratory values were also measured. Seven items were preserved in the adapted appetite questionnaire, with two factors associated with flavor and gastric fullness (Cronbach’s alpha = 0.758). Diminished appetite was identified with a cut-off value ≤25 points (sensitivity 73%, specificity 77%). Patients with diminished appetite had a higher proportion of females and DMS punctuation, lower plasmatic level of creatinine, blood urea nitrogen, and phosphorus. Appetite score correlated with BDI score, BAI score and DTS. Conclusions: This simple but robust appetite score adequately discriminates against patients with diminished appetite. Screening and treatment of psychological conditions may be useful to increase appetite and the nutritional status of these patients.

Modelling the Cost-Effectiveness of Implementing a Dietary Intervention in Renal Transplant Recipients

Background: The Dietary Approach to Stop Hypertension (DASH) and potassium supplementation have been shown to reduce the risk of death with a functioning graft (DWFG) and renal graft failure in renal transplant recipients (RTR). Unfortunately, a key problem for patients is the adherence to these diets. The aim of this study is to evaluate the cost-effectiveness and budget impact of higher adherence to either the DASH or potassium supplementation. Methods: A Markov model was used to simulate the life course of 1000 RTR in the Netherlands. A societal perspective with a lifetime time horizon was used. The potential effect of improvement of dietary adherence was modelled in different scenarios. The primary outcomes are the incremental cost-effectiveness ratio (ICER) and the budget impact. Results: In the base case, improved adherence to the DASH diet saved 27,934,786 and gained 1880 quality-adjusted life years (QALYs). Improved adherence to potassium supplementation saved €1,217,803 and gained 2901 QALYs. Both resulted in dominant ICERs. The budget impact over a five-year period for the entire Dutch RTR population was €8,144,693. Conclusion: Improving dietary adherence in RTR is likely to be cost-saving and highly likely to be cost-effective compared to the current standard of care in the Netherlands.

Dietary intake in adults on hemodialysis compared with guideline recommendations

Background

Clinical practice guidelines of dietary management are designed to promote a balanced diet and maintain health in patients undergoing haemodialysis but they may not reflect patients’ preferences. We aimed to investigate the consistency between the dietary intake of patients on maintenance haemodialysis and guideline recommendations.

Methods

Cross-sectional analysis of the DIET-HD study, which included 6,906 adults undergoing haemodialysis in 10 European countries. Dietary intake was determined using the Global Allergy and Asthma European Network (GA²LEN) Food Frequency Questionnaire (FFQ), and compared with the European Best Practice Guidelines. Consistency with guidelines was defined as achieving the minimum daily recommended intake for energy (≥ 30 kcal/kg) and protein (≥ 1.1 g/kg), and not exceeding the maximum recommended daily intake for phosphate (≤ 1000 mg), potassium (≤ 2730 mg), sodium (≤ 2300 mg) and calcium (≤ 800 mg).

Results

Overall, patients’ dietary intakes of phosphate and potassium were infrequently consistent with guidelines (consistent in 25% and 25% of patients, respectively). Almost half of the patients reported that energy (45%) and calcium intake (53%) was consistent with the guidelines, while the recommended intake of sodium and protein was consistent in 85% and 67% of patients, respectively. Results were similar across all participating countries. Intake was consistent with all six guideline recommendations in only 1% of patients.

Conclusion

Patients on maintenance haemodialysis usually have a dietary intake which is inconsistent with current recommendations, especially for phosphate and potassium.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40620-020-00962-3.

Medical Foods: Science, Regulation, and Practical Aspects. Summary of a Workshop

On August 13-14, 2019, the Healthcare Nutrition Council and the ASN held the Medical Foods Workshop: Science, Regulation, and Practical Aspects. Medical food products help patients manage their disease and improve their quality of life. Yet many hurdles exist to getting patients new products. In this workshop, participants addressed some of these hurdles, with specific emphasis on topics like the statutory term distinctive nutritional requirements, the regulatory term modification of the diet alone, the role of clinical guidelines, the requirement that medical foods be used under medical supervision, and differentiation of foods for special dietary use from medical foods, as well as product innovation and future research. Real-world examples were discussed for intractable epilepsy, diabetes, end-stage renal disease, and inflammatory bowel disease.

Chronic Kidney Disease, Gut Dysbiosis, and Constipation: A Burdensome Triplet

Gut dysbiosis has been implicated in the progression of chronic kidney disease (CKD). Alterations in the gut environment induced by uremic toxins, the dietary restriction of fiber-rich foods, and multiple drugs may be involved in CKD-related gut dysbiosis. CKD-related gut dysbiosis is considered to be characterized by the expansion of bacterial species producing precursors of harmful uremic toxins, such as indoxyl sulfate and p-cresyl sulfate, and the contraction of species generating beneficial short-chain fatty acids, such as butyrate. Gut-derived uremic toxins cause oxidative stress and pro-inflammatory responses, whereas butyrate exerts anti-inflammatory effects and contributes to gut epithelial integrity. Gut dysbiosis is associated with the disruption of the gut epithelial barrier, which leads to the translocation of endotoxins. Research on CKD-related gut dysbiosis has mainly focused on chronic inflammation and consequent cardiovascular and renal damage. The pathogenic relationship between CKD-related gut dysbiosis and constipation has not yet been investigated in detail. Constipation is highly prevalent in CKD and affects the quality of life of these patients. Under the pathophysiological state of gut dysbiosis, altered bacterial fermentation products may play a prominent role in intestinal dysmotility. In this review, we outline the factors contributing to constipation, such as the gut microbiota and bacterial fermentation; introduce recent findings on the pathogenic link between CKD-related gut dysbiosis and constipation; and discuss potential interventions. This pathogenic link needs to be elucidated in more detail and may contribute to the development of novel treatment options not only for constipation, but also cardiovascular disease in CKD.

Association between Serum Uric Acid Levels, Nutritional and Antioxidant Status in Patients on Hemodialysis

Purpose: To determine the relationship between uric acid (UA) and nutritional and antioxidant status in hemodialysis (HD) patients, given that hyperuricemia could be an indicator of good nutritional status possibly because of the antioxidant properties of UA. Methods: Cross-sectional study with 93 patients on HD. Hyperuricemia was considered as UA ≥6.0 mg/dL in females and ≥7.0 mg/dL in males. Nutritional variables were registered. Blood samples were taken before the dialysis session to determine oxidative damage as plasma malondialdehyde (MDA) content, and antioxidant capacity measuring 2,2-diphenyl-piclrylhidrazil radical (DPPH^●) scavenging activity and oxygen radical absorbance capacity (ORAC) value. Results: Patients with hyperuricemia had higher creatinine (11.9 vs. 10.5 mg/dL; p = 0.004), potassium (5.5 vs. 5.0 mg/dL; p = 0.014) levels; phase angle (5.8 vs. 4.9; p = 0.005), protein consumption (normalized protein nitrogen appearance, nPNA, 1.03 vs. 0.83; p = 0.013) than normouricemic patients. DPPH^● scavenging activity was higher in hyperuricemic subjects (1.139 vs. 1.049 mM Trolox equivalents; p = 0.007); likewise, hyperuricemic subjects had less oxidant damage measured by MDA (10.6 vs. 12.7 nmol/mL; p = 0.020). Subjects with normouricemia were at higher risk of having a reactance to height (Xc/H) ratio less than 35 (OR 2.79; 95% CI, 1.1–7.017, p = 0.028); nPNA < 1.0 (OR 3.78; 95% CI, 1.4–10.2, p = 0.007), diagnosis of cachexia (OR 2.95; 95% CI, 1156–7.518, p = 0.021), potassium levels <5 (OR 2.97; 95% CI, 1.136–7.772, p = 0.023) and PA < 5.5° (OR 3.38; 95% CI, 1.309–8.749, p = 0.012.) Conclusions: Patients with hyperuricemia had higher antioxidant capacity and better nutritional status. Purines and protein restrictions in HD patients with hyperuricemia need to be reviewed individually for each patient. More studies are needed to stablish a cut point of UA levels in renal population.

A Dietary Mobile App for Patients Undergoing Hemodialysis: Prospective Pilot Study to Improve Dietary Intakes

Background

Mobile technology has an impact on the health care sector, also within dietetics. Mobile health (mHealth) apps may be used for dietary assessment and self-monitoring, allowing for real-time reporting of food intakes. Changing eating behaviors is quite challenging, and patients undergoing hemodialysis, particularly, struggle to meet the target intakes set by dietary guidelines. Usage of mobile apps that are developed in a person-centered approach and in line with recommendations may support both patients and health care practitioners.

Objective

This study is a pilot that aims at estimating the potential efficacy of a dietary intervention using a theory-based, person-centered smartphone app. Results will be used to improve both the app and a planned large-scale trial intended to assess app efficacy thoroughly.

Methods

A prospective pilot study was performed at the hemodialysis unit of Al Qassimi Hospital (The Emirate of Sharjah). All patients that fulfilled the study inclusion criteria were considered eligible to be enrolled in the pilot study. Upon successful installation of the app, users met with a dietitian once a week. Outcomes were measured at baseline (T0) and 2 weeks post app usage (T1). This pilot is reported as per guidelines for nonrandomized pilot and feasibility studies and in line with the CONSORT 2010 checklist for reporting pilot or feasibility trials.

Results

A total of 23 patients completed the pilot intervention. Mean energy intakes increased from 24.4 kcal/kg/day (SD 8.0) to 29.1 kcal/kg/day (SD 7.8) with a medium effect size (d=0.6, 95% CI 0.0-1.2). Mean protein intakes increased from 0.9 g/kg/day (SD 0.3) to 1.3 g/kg/day (SD 0.5) with a large effect size (d=1.0, 95% CI 0.4-1.6); mean intake of high biological value (%HBV) proteins also increased from 58.6% (SD 10.1) to 70.1% (SD 10.7) with a large effect size (d=1.1, 95% CI 0.5-1.7). Dietary intakes of minerals did not change, apart from sodium which decreased from a mean intake of 2218.8 mg/day (SD 631.6) to 1895.3 mg/day (SD 581.0) with a medium effect size (d=0.5, 95% CI 0.1-1.1). Mean serum phosphorus, potassium, and albumin levels did not change relevantly. Mean serum iron increased from 7.9 mg/dL (SD 2.8) to 11.5 mg/dL (SD 7.9) postintervention with a medium effect size (d=0.6, 95% CI 0.0-1.2).

Conclusions

This pilot study showed that the KELA.AE app has the potential to improve dietary intakes. Processes related to procedure, resources, tools, and app improvement for a future trial were assessed. A more extended intervention using a randomized controlled trial is required to estimate parameters concerning app efficacy accurately.

Healthy Eating Index of Living Donor Renal Transplantation Recipients During the First Year Posttransplant

BACKGROUND

The aim of this study was to examine the relationship between diet quality and weight gain in kidney transplant recipients from pretransplant baseline through posttransplant at 3 months and 1 year.

METHODS

Data from a prospective, observational cohort study of kidney transplant patients (n = 26) were analyzed. Participants were adult (aged 18-65 years), living donor kidney transplant recipients who were participating in a prospective body composition study. Body weight, body mass index, dietary intake, and Healthy Eating Index scores were used to assess changes in weight, nutrient intake, and diet quality.

FINDINGS

At the time of kidney transplantation, 42% (n = 11) were obese and 27% (n = 7) were overweight. Weight significantly increased from transplantation to 12 months (mean [SD]: 83 [18] kg and 90 [18] kg, respectively; mean change 8.4%, P = .002). At 12 months posttransplant, dietary fat intake significantly increased (P = .033). Body weight was strongly correlated with total dietary fat intake (r = 0.56, P = .003). The Healthy Eating Index total scores at baseline and 1-year posttransplant were not significantly different (45.75 [14.99] and 42.59 [12.70]). Likewise, component scores did not change from pretransplant to posttransplant.

DISCUSSION

Diet quality of transplant recipients was poor both before and after transplantation. Using the Healthy Eating Index confirmed that improvements in food intake are needed. Further research is warranted to identify dietary recommendations for the prevention of excessive weight gain and the potential adverse health complications following kidney transplantation.

Plant-based diets to manage the risks and complications of chronic kidney disease

Traditional dietary recommendations for patients with chronic kidney disease (CKD) focus on the quantity of nutrients consumed. Without appropriate dietary counselling, these restrictions can result in a low intake of fruits and vegetables and a lack of diversity in the diet. Plant nutrients and plant-based diets could have beneficial effects in patients with CKD: increased fibre intake shifts the gut microbiota towards reduced production of uraemic toxins; plant fats, particularly olive oil, have anti-atherogenic effects; plant anions might mitigate metabolic acidosis and slow CKD progression; and as plant phosphorus has a lower bioavailability than animal phosphorus, plant-based diets might enable better control of hyperphosphataemia. Current evidence suggests that promoting the adoption of plant-based diets has few risks but potential benefits for the primary prevention of CKD, as well as for delaying progression in patients with CKD G3-5. These diets might also help to manage and prevent some of the symptoms and metabolic complications of CKD. We suggest that restriction of plant foods as a strategy to prevent hyperkalaemia or undernutrition should be individualized to avoid depriving patients with CKD of these potential beneficial effects of plant-based diets. However, research is needed to address knowledge gaps, particularly regarding the relevance and extent of diet-induced hyperkalaemia in patients undergoing dialysis.

Effect of a Nutritional Intervention, Based on Transtheoretical Model, on Metabolic Markers and Food Consumption of Individuals Undergoing Hemodialysis

OBJECTIVE

This study aimed to evaluate the effect of a nutritional intervention, based on the transtheoretical model, on the metabolic markers and dietary intake of individuals undergoing hemodialysis (HD).

METHODS

Intervention study at a nephrology clinic includes 83 individuals undergoing HD, over a period of 4 months. The nutritional intervention based on the transtheoretical model was composed of two group meetings and three individual ones, with delivery of personalized food plans and nutritional education activities. Anthropometry, dietary intake, metabolic markers, and stage of behavior change were evaluated before and after nutritional intervention.

RESULTS

There was a significant change from the stage of contemplation to the stage of action, after the intervention (P < .001). There was a significant reduction in serum concentrations of creatinine and predialysis and postdialysis urea (P < .001). Hyperphosphataemia and hyperkalemia in the group were also significantly reduced as were markers related to bone metabolism (P < .001). The markers of iron metabolism (P < .001), protein (P = .042), and globulin (P < .001) showed a significant increase. Regarding food consumption, the caloric intakes (P = .034), cholesterol (P = .034), protein, and lipid as well as intake of iron, phosphorus, potassium, copper, and vitamin C (P < .001) were significantly higher after intervention.

CONCLUSIONS

The nutritional intervention based on the transtheoretical model promoted a change in the behavior of individuals undergoing HD, with an important improvement in their metabolic control. This can be explained by the significant change in the intake of calories, macronutrients, and micronutrients, as well as adequate use of phosphorus binders, indicating the crucial role of nutrition in this group.

Dietary Daily Sodium Intake Lower than 1500 mg Is Associated with Inadequately Low Intake of Calorie, Protein, Iron, Zinc and Vitamin B1 in Patients on Chronic Hemodialysis

Background: To measure daily sodium intake in patients on chronic hemodialysis and to compare the intake of nutrients, minerals, trace elements, and vitamins in patients who had a daily sodium intake below or above the value of 1500 mg recommended by the American Heart Association. Methods: Dietary intake was recorded for 3 days by means of 3-day diet diaries in prevalent patients on chronic hemodialysis. Each patient was instructed by a dietitian on how to fill the diary, which was subsequently signed by a next of kin. Results: We studied 127 patients. Mean sodium intake (mg) was 1295.9 ± 812.3. Eighty-seven (68.5%) patients had a daily sodium intake <1500 mg (group 1) and 40 (31.5%) ≥ 1500 mg (group 2). Correlation between daily sodium intake and daily calorie intake was significant (r = 0.474 [0.327 to 0.599]; p < 0.0001). Daily calorie intake (kcal/kg/day) was lower in group 1 (21.1 ± 6.6; p = 0.0001) than in group 2 (27.1 ± 10.4). Correlation between daily sodium intake and daily protein intake was significant (r = 0.530 [0.392 to 0.644]; p < 0.0001). The daily protein intake (grams/kg/day) was lower in group 1 (0.823 ± 0.275; p = 0.0003) than in group 2 (1.061 ± 0.419). Daily intake of magnesium, copper, iron, zinc, and selenium was significantly lower in group 1 than in group 2. Daily intake of vitamin A, B2, B3, and C did not differ significantly between group 1 and group 2. Daily intake of vitamin B1 was significantly lower in group 1 than in group 2. Significantly lower was, in group 1 than in group 2, the percentage of patients within the target value with regard to intake of calories (11.5% vs. 37.5%; p = 0.001) and proteins (9.2% vs. 27.5%; p = 0.015) as well as of iron (23% vs. 45%; p = 0.020), zinc (13.8% vs. 53.8%; p = 0.008) and vitamin B1 (8.1% vs. 50%; p < 0.001). Conclusion: A low daily intake of sodium is associated with an inadequately low intake of calorie, proteins, minerals, trace elements, and vitamin B1. Nutritional counselling aimed to reduce the intake of sodium in patients on chronic hemodialysis should not disregard an adequate intake of macro- and micronutrients, otherwise the risk of malnutrition is high.

A Renal Clinician's Guide to the Gut Microbiota

It is increasingly recognized that the gut microbiota plays a role in the progression of chronic diseases and that diet may confer health benefits by altering the gut microbiota composition. This is of particular relevance for chronic kidney disease (CKD), as the gut is a source of uremic retention solutes, which accumulate as a result of impaired kidney function and can exert nephrotoxic and other harmful effects. Kidney dysfunction is also associated with changes in the composition of the gut microbiota and the gastrointestinal tract. Diet modulates the gut microbiota, and there is much interest in the use of prebiotics, probiotics, and synbiotics as dietary therapies in CKD, as well as dietary patterns that beneficially alter the microbiota. This review provides an overview of the gut microbiota and its measurement, its relevance in the context of CKD, and the current state of knowledge regarding dietary manipulation of the microbiota.

Constipation in chronic kidney disease: it is time to reconsider

Constipation is highly prevalent in patients with chronic kidney disease (CKD) and is primarily characterized by decreased intestinal motility. This chronic disorder affects the quality of life of patients. However, nephrologist and dialysis clinicians have long had a disproportionately limited understanding of constipation. Accumulating evidence has revealed a relationship between constipation and cardiovascular disease and CKD. The pathogenesis of constipation in CKD patients is multifactorial: decreased physical activity, comorbidities affecting bowel movement, such as diabetes mellitus, cerebrovascular disease, and hyperparathyroidism, a restricted dietary intake of plant-based fiber-rich foods, and multiple medications, including phosphate binders and potassium-binding resins, have all been implicated. CKD is associated with alterations in the composition and function of the gut microbiota, so-called gut dysbiosis. Recent studies showed that CKD-related gut dysbiosis decreased intestinal motility via intestinal inflammation or the increased generation of gut-derived uremic toxins, such as indoxyl sulfate and p-cresyl sulfate. Furthermore, the gastrointestinal secretion of mucin was found to be decreased in CKD animal models, which may delay colonic transit by diminished lubrication in the alimentary tract. Thus, CKD-related gut dysbiosis may play a role in constipation, but limited information is currently available. Since constipation is often intractable, particularly in CKD patients, every available means needs to be employed in its treatment. The effects of probiotics, prebiotics, and synbiotics on the composition of the gut microbiota and gut-derived uremic toxins have been increasingly reported. However, their effects on stool consistency or frequency in CKD patients remain unclear. Some laxatives may be beneficial for improving not only bowel habits but also gut dysbiosis. Further studies are required to elucidate the CKD-specific pathogenesis of constipation and develop novel effective treatment options.

Factors associated with adherence to dietary prescription among adult patients with chronic kidney disease on hemodialysis in national referral hospitals in Kenya: a mixed-methods survey

Introduction

Adherence to dietary prescriptions among patients with chronic kidney disease is known to prevent deterioration of kidney functions and slow down the risk for morbidity and mortality. This study determined factors associated with adherence to dietary prescription among adult patients with chronic kidney disease on hemodialysis.

Methods

A mixed-methods study, using parallel mixed design, was conducted at the renal clinics and dialysis units at the national teaching and referral hospitals in Kenya from September 2018 to January 2019. The study followed a QUAN + qual paradigm, with quantitative survey as the primary method. Adult patients with chronic kidney disease on hemodialysis without kidney transplant were purposively sampled for the quantitative survey. A sub-sample of adult patients and their caregivers were purposively sampled for the qualitative survey. Numeric data were collected using a structured, self-reported questionnaire using Open Data Kit “Collect software” while qualitative data were collected using in-depth interview guides and voice recording. Analysis on STATA software for quantitative and NVIV0 12 for qualitative data was conducted. The dependent variable, “adherence to diet prescription” was analyzed as a binary variable. P values < 0.1 and < 0.05 were considered as statistically significant in univariate and multivariate logistic regression models respectively. Qualitative data were thematically analyzed.

Results

Only 36.3% of the study population adhered to their dietary prescriptions. Factors that were independently associated with adherence to diet prescriptions were “flexibility in the diets” (AOR 2.65, 95% CI 1.11–6.30, P 0.028), “difficulties in following diet recommendations” (AOR 0.24, 95% CI 0.13–0.46, P < 001), and “adherence to limiting fluid intake” (AOR 9.74, 95% CI 4.90–19.38, P < 0.001).

Conclusions

For patients with chronic kidney disease on hemodialysis, diet prescriptions with less restrictions and requiring minimal extra efforts and resources are more likely to be adhered to than the restrictive ones. Patients who adhere to their fluid intake restrictions easily follow their diet prescriptions. Prescribed diets should be based on the individual patient’s usual dietary habits and assessed levels of challenges in using such diets. Additionally, diet adherence messages should be integrated with fluid limitation messages. Further research on understanding patients’ adherence to fluid restriction is also suggested.

Baseline Serum Magnesium Level and Its Variability in Maintenance Hemodialysis Patients: Associations with Mortality

BACKGROUND/AIMS

The study aimed at investigating the impact of serum magnesium (Mg) baseline level and its variability on mortality in maintenance hemodialysis (MHD) patients.

METHODS

Eligible patients receiving regular MHD at Ningbo No. 2 Hospital between January 2009 and August 2016 were enrolled and follow-ups were conducted afterwards until death or transplantation. General information, laboratory results, and outcomes of subjects were collected. The relationship between baseline serum Mg level, its coefficient of variation (CV), and all-cause mortality and cardiovascular disease mortality were assessed, respectively. Subjects were divided into groups in 2 manners: by serum Mg level (lower Mg group: serum Mg <1.00 mmol/L, higher Mg group: serum Mg ≥1.00 mmol/L) and by serum Mg CV (high variation group: CV ≥0.149 mmol/L, middle variation group: 0.114 mmol/L ≤ CV < 0.149 mmol/L, and low variation group: CV <0.114 mmol/L).

RESULTS

169 MHD patients were recruited in the study, with mean serum Mg 1.00 ± 0.18 mmol/L, average age 60.20 ± 15.64 years, and median dialysis duration 37.00 (18.30, 77.97) months. During the follow-up, 69 (40.83%) patients died, 24 (34.78%) of which died due to cardiovascular disease. Comparing the two groups, patients in the lower Mg group had a higher all-cause mortality (50.00 vs. 29.33%, p = 0.007). The multivariate Cox regression analysis suggested that lower Mg level was an independent factor for all-cause mortality as well as cardiovascular mortality (HR = 13.268, 95% CI 6.234-28.237, p < 0.001; HR = 12.702, 95% CI 3.737-43.174, p < 0.001, respectively). However, there were no significant statistical differences of all-cause and cardiovascular mortality among these three groups concerning Mg variation. And in the univariate and multivariate Cox regression analysis, serum magnesium CV was not the independent factor for all-cause mortality and cardiovascular mortality.

CONCLUSIONS

The lower baseline serum magnesium level was associated with all-cause and cardiovascular mortality in MHD patients. However, the variability of magnesium level was not independently associated with the risk of death and further studies need to be conducted.

Dietary fatty acid intake in hemodialysis patients and associations with circulating fatty acid profiles: A cross-sectional study

OBJECTIVES

The aims of this study were threefold: first, to assess the dietary fatty acid (FA) intake and blood FA status in Malaysian patients on hemodialysis (HD); second, to examine the association between dietary FA intakes and blood FA profiles in patients on HD; and third, to determine whether blood FAs could serve as a biomarker of dietary fat intake quality in these patients.

METHODS

Using 3 d of dietary records, FA intakes of 333 recruited patients were calculated using a food database built from laboratory analyses of commonly consumed Malaysian foods. Plasma triacylglycerol (TG) and erythrocyte FAs were determined by gas chromatography.

RESULTS

High dietary saturated fatty acid (SFA) and monounsaturated fatty acid (MUFA) consumption trends were observed. Patients on HD also reported low dietary ω-3 and ω-6 polyunsaturated fatty acid (PUFA) consumptions and low levels of TG and erythrocyte FAs. TG and dietary FAs were significantly associated respective to total PUFA, total ω-6 PUFA, 18:2 ω-6, total ω-3 PUFA, 18:3 ω-3, 22:6 ω-3, and trans 18:2 isomers (P < 0.05). Contrarily, only dietary total ω-3 PUFA and 22:6 ω-3 were significantly associated with erythrocyte FAs (P < 0.01). The highest tertile of fish and shellfish consumption reflected a significantly higher proportion of TG 22:6 ω-3. Dietary SFAs were directly associated with TG and erythrocyte MUFA, whereas dietary PUFAs were not.

CONCLUSION

TG and erythrocyte FAs serve as biomarkers of dietary PUFA intake in patients on HD. Elevation of circulating MUFA may be attributed to inadequate intake of PUFAs.

Apple intake improves antioxidant parameters in hemodialysis patients without affecting serum potassium levels

Oxidative stress (OS) is associated with increased morbidity and mortality in hemodialysis (HD) patients, and the consumption of fruits seems to improve OS due to their antioxidant properties. Therefore, we hypothesized that Fuji apple intake improves OS markers in HD patients due to its polyphenolic compounds without increasing serum potassium levels. This trial was a 1-group, pre- and posttest comparison between 16 patients who had been on hemodialysis for at least 3 months without any acute illness or hyperkalemia. Each volunteer consumed 2 Fuji apples (~360 g) per day for 1 week. Blood samples were collected at the baseline period and after 8 days for the measurement of total antioxidant status, ascorbic acid, catalase, glutathione peroxidase, superoxide dismutase, reduced glutathione, total oxidant status, oxidative stress index, potassium, phosphorus, uric acid, glucose, and fructosamine. For tolerance evaluation, participants were asked about their bowel habits. Apple intake increased glutathione peroxidase (P = .006) and superoxide dismutase activities (P = .006) and ascorbic acid levels (P = .002). No significant changes were observed in uric acid, potassium, phosphorus, glucose, and fructosamine levels. Additionally, there was a decrease in the catalase activity (P = .021) and in the total antioxidant status values (P = .004). However, increased total oxidant status (P = .003) and oxidative stress index (P = .033) levels were observed after apple intake. In conclusion, the intake of 2 Fuji apples per day for 1 week was well tolerated and improved antioxidant parameters in HD patients without affecting serum potassium levels.

Pruritus in hemodialysis patients: association with phosphorus intake and serum calcium level

OBJECTIVE

To analyze the association between the occurrence of pruritus and adherence to the prescribed diet, biochemical indicators of renal function and the quality of hemodialysis in chronic renal patients.

METHOD

A cross-sectional study performed at a dialysis clinic in the Northeast of Brazil, with 200 patients undergoing hemodialysis in the first half of 2015.To analyze the data, inferential statistics were used, using Chi-Square and Fisher's Exact tests; and Mann Whitney U test.

RESULTS

The pruritus was present in 51% of the sample, being associated statistically with phosphorus consumption (P = 0.024) and elevation of serum calcium (P = 0.009).

CONCLUSION

Pruritus in chronic renal patients undergoing hemodialysis is influenced by adequate nonadherence to the prescribed diet, in addition to the elevation of biochemical indicators of renal function.

Associations of dietary macronutrients and micronutrients with the traditional and nontraditional risk factors for cardiovascular disease among hemodialysis patients: A clinical cross-sectional study

The current study was to examine the association of adequate intake of macronutrients and micronutrients with traditional and nontraditional cardiovascular risk factors in hemodialysis patients.A clinical cross-sectional study was conducted between September 2013 and April 2017 on 492 hemodialysis patients aged 20 years and above, received thrice-weekly hemodialysis treatment for at least 3 months, adequate dialysis quality (equilibrated Kt/V ≥ 1.2 g/kg/d) from 7 hospital-based hemodialysis centers in Taiwan. The dietary intake was evaluated by the 3-day dietary record, and a 24-hour dietary recall. Biochemical parameters were archived from laboratory tests. The cardiovascular disease (CVD) risk factors were defined by the Kidney Disease Outcomes Quality Initiative (K/DOQI) Clinical Practice Guidelines. The adequate dietary intake of macronutrients and micronutrients was recommended by the European Best Practice Guidelines, K/DOQI, and Institute of Medicine guidelines. Logistic regression analysis was used.All hemodialysis patients had CVD risks, the lowest proportion of patients with adequate intake of macronutrients and micronutrients were 8.7% and 1.8%, respectively. The adequate dietary intake associated with lower likelihood of having CVD risks in hemodialysis patient by 47% to 84%, including 39% to 58% lower hypertension, 37% to 50% lower dyslipidemia, 42% to 63% diabetes mellitus, 44% to 84% lower obesity, 58% lower low calcium, 38% lower hyperparathyroidism, 47% to 64% lower hyperhomocysteinemia, and 41% to 67% lower inflammation, 63% to 74% lower hypoalbumin, 73% lower inadequate normalized protein nitrogen appearance.Adequate dietary nutrients intake may reduce the cardiovascular risks factors, in turn, to prevent the cardiovascular morbidity and mortality.