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

The association between a low-carbohydrate diet score and the risk of diabetic nephropathy in women: A case-control study

OBJECTIVES

Because evidence linking carbohydrate consumption to diabetic nephropathy (DN) is scarce, and the association between a low-carbohydrate diet (LCD) and DN has not been investigated, we sought to investigate whether a higher LCD score is associated with DN among women.

METHODS

In a case-control study, 105 women with type 2 diabetes mellitus and DN and 105 controls with type 2 diabetes mellitus and without DN who attended Kowsar Diabetes Clinic in Semnan, Iran, were matched for age and diabetes duration. The data related to anthropometric and biochemical measures were collected and a food frequency questionnaire with 147 items was used to assess dietary intake. Based on the food frequency questionnaire, we calculated an LCD score for each study participant. Multivariate logistic regression was performed to examine the association between an LCD score and the odds of developing DN.

RESULTS

The results of the study demonstrated that the LCD score was not significantly associated with DN in the crude model (odds ratio = 0.39; 95% confidence interval, 0.14-1.07; P = 0.06). However, after adjusting for several confounders, subjects in the top quartile of the LCD score were associated with a 71% lower risk of DN (odds ratio [OR] = 0.29; 95% confidence interval, 0.10-0.86; P = 0.02). A significant trend toward decreased urinary albumin excretion was found with an increase in the LCD score (P = 0.005).

CONCLUSIONS

A diet low in carbohydrates was inversely associated with risk of DN. Further observational studies, and preferably randomized controlled trials, are needed to confirm the present results.

Exploring stakeholder experiences of dietetic service and care delivery: A systematic qualitative review

BACKGROUND

There is limited understanding of patients' and healthcare professionals' perceptions and experiences of receiving and delivering dietetic care, respectively. This systematic review of the literature used qualitative synthesis to explore the perceptions and experiences of multiple stakeholders involved in the delivery of nutrition care and dietetic service.

METHODS

MEDLINE, Embase, CINAHL, Cochrane Library, Scopus, ISI Web of Science, PsycINFO and ProQuest were systematically searched. Study characteristics and perceptions of stakeholders regarding nutrition care services were extracted. Qualitative synthesis was employed and thematic analysis conducted.

RESULTS

Five themes were identified from 44 studies related to stakeholders' perceptions of dietetic services. Studies included quantitative, qualitative and mixed methods involving patients, families, dietitians and other healthcare professionals. The themes were (1) patients desiring a personalised approach to nutrition care; (2) accessing dietetic service; (3) perceived impact of nutrition care on the patient; (4) relationships between stakeholders; and (5) beliefs about nutrition expertise. Two themes were specific to patients; these were the desire for individualised care and the impact of nutrition care. Within each theme perceptions varied with patients' views often contrasting with those of dietetic service providers.

CONCLUSIONS

Experiences of dietetic service do not always meet stakeholder expectations which impacts on patient engagement. Seeking stakeholder input is imperative to design dietetic services that engage patients in positive and supportive clinical partnerships.

Sesamolin Attenuates Kidney Injury, Intestinal Barrier Dysfunction, and Gut Microbiota Imbalance in High-Fat and High-Fructose Diet-Fed Mice

This study investigated the effects of sesamolin on kidney injury, intestinal barrier dysfunction, and gut microbiota imbalance in high-fat and high-fructose (HF-HF) diet-fed mice and explored the underlying correlations among them. The results indicated that sesamolin suppressed metabolic disorders and increased renal function parameters. Histological evaluation showed that sesamolin mitigated renal epithelial cell degeneration and brush border damage. Meanwhile, sesamolin inhibited the endotoxin-mediated induction of the Toll-like receptor 4-related IKKα/NF-κB p65 pathway activation. Additionally, sesamolin mitigated intestinal barrier dysfunction and improved the composition of gut microbiota. The correlation results further indicated that changes in the dominant phyla, including Firmicutes, Deferribacterota, Desulfobacterota, and Bacteroidota, were more highly correlated with a reduction in endotoxemia and metabolic disorders, as well as decreases in intestinal proinflammatory response and related renal risk biomarkers. The results of this study suggest that sesamolin attenuates kidney injuries, which might be associated with its effects on the reduction of endotoxemia and related metabolic disorders through the restoration of the intestinal barrier and the modulation of gut microbiota. Thus, sesamolin may be a potential dietary supplement for protection against obesity-associated kidney injury.

Effects of Mediterranean Diet, DASH Diet, and Plant-Based Diet on Outcomes among End Stage Kidney Disease Patients: A Systematic Review and Meta-Analysis

BACKGROUND

The Mediterranean, Dietary Approach to Stop Hypertension (DASH), and plant-based diets may provide cardiovascular benefit to the general population. However, data on their effect on end stage kidney disease (ESKD) patients are limited. This systematic review aims to assess the impact of Mediterranean, DASH, and plant-based diets on outcomes among ESKD patients.

METHODS

A literature review was conducted in EMBASE, MEDLINE, and Cochrane databases from inception through September 2022 to identify studies that assess the clinical outcomes of Mediterranean, DASH, or plant-based diets on ESKD patients on hemodialysis (HD) or peritoneal dialysis (PD). Effect estimates from the individual studies were derived utilizing the random-effect, generic inverse variance approach of DerSimonian and Laird.

RESULTS

Seven studies with 9400 ESKD patients (8395 HD and 1005 PD) met the eligibility criteria and were included in the data analysis. Pooled odds ratios (ORs) of mortality for ESKD patients who adhered to the Mediterranean versus plant-based diet were 0.49 (95% CI: 0.07-3.54; two studies, I² = 67%) and 0.87 (95% CI: 0.75-1.01; two studies, I² = 0%), respectively. Data on mortality for ESKD patients on a DASH diet were limited to one study with an OR of 1.00 (95% CI: 0.89-1.12). The pooled OR of cardiovascular mortality among ESKD patients who adhered to a plant-based diet was 0.86 (95% CI: 0.68-1.08; two studies, I² = 0%), compared to those who did not. Data on cardiovascular mortality among those with Mediterranean and DASH diet were limited to one study with ORs of 1.14 (95% CI: 0.90-1.43) and 1.19 (95% CI: 0.99-1.43), respectively. Mediterranean diet adherence was found to be associated with reduced risk of left ventricular hypertrophy (LVH) with an OR of 0.82 (95% CI: 0.68-0.99) in a study including 127 ESKD patients. The risk of hyperkalemia was not significant among those with a plant-based diet with an OR of 1.00 (95% CI: 0.94-1.07) in a study including 150 ESKD patients.

CONCLUSIONS

While our systematic review demonstrated no significant associations of Mediterranean, DASH, and plant-based diets with reduced all-cause mortality or cardiovascular mortality, there was also no evidence that suggested harmful effects of these diets to ESKD patients.

The Impact of a Mediterranean-like Diet with Controlled Protein Intake on the Onco-Nephrological Scenario: Time for a New Perspective

Chronic kidney disease (CKD) represents a frequent comorbidity in cancer patients, especially for patients affected by urological cancers. Unfortunately, impaired kidney function may limit the choice of adequate oncological treatments for their potential nephrotoxicity or due to contraindications in case of a low glomerular filtration rate. For these patients, tailored nephrological and nutritional management is mandatory. The K-DIGO guidelines do not define whether the nutritional management of CKD could be useful also in CKD patients affected by urological cancer. In fact, in clinical practice, oncological patients often receive high-protein diets to avoid malnutrition. In our study, we investigated the nutritional and nephrological impact of a Mediterranean-like diet with a controlled protein intake (MCPD) on a cohort of 82 stage III-IV CKD patients. We compared two cohorts: one of 31 non-oncological CKD patients and the other of 51 oncological patients with CKD. The use of an MCPD had a favorable impact on both the oncological and non-oncological CKD patients with an amelioration in all the investigated parameters and with a better quality of life, with no cases of malnutrition or AKI.

Hypercaloric Diet Promotes Metabolic Disorders and Impaired Kidney Function

Poor dietary habits such as overconsumption of hypercaloric diets characterized by a high content of fructose and fat are related to metabolic abnormalities development such as obesity, diabetes, and dyslipidemia. Accumulating evidence supports the hypothesis that if energy intake gradually exceeds the body's ability to store fat in adipose tissue, the prolonged metabolic imbalance of circulating lipids from endogenous and exogenous sources leads to ectopic fat distribution in the peripheral organs, especially in the heart, liver, and kidney. The kidney is easily affected by dyslipidemia, which induces lipid accumulation and reflects an imbalance between fatty acid supply and fatty acid utilization. This derives from tissue lipotoxicity, oxidative stress, fibrosis, and inflammation, resulting in structural and functional changes that lead to glomerular and tubule-interstitial damage. Some authors indicate that a lipid-lowering pharmacological approach combined with a substantial lifestyle change should be considered to treat chronic kidney disease (CKD). Also, the new therapeutic target identification and the development of new drugs targeting metabolic pathways involved with kidney lipotoxicity could constitute an additional alternative to combat the complex mechanisms involved in impaired kidney function. In this review article, we first provide the pathophysiological evidence regarding the impact of hypercaloric diets, such as high-fat diets and high-fructose diets, on the development of metabolic disorders associated with impaired renal function and the molecular mechanisms underlying tissue lipid deposition. In addition, we present the current progress regarding translational strategies to prevent and/or treat kidney injury related to the consumption of hypercaloric diets.

Using a Short Food Frequency Questionnaire to Evaluate Macronutrients, Fiber, Phosphorus, Potassium, and Calcium in Adults with Stages 3-5 Chronic Kidney Disease

The progression of chronic kidney disease (CKD) can be directly or indirectly accelerated by a poor diet and the diet's influence on risk factors for this disease. There have been no food frequency questionnaires (FFQs) developed for the assessment of diet in patients with CKD in Taiwan. This study analyzed the validity of a short FFQ (SFFQ) with 42 items for estimating patient intake of macronutrients, fiber, phosphorus, potassium, and calcium against 3-day dietary records (3-day DRs) in Taiwanese patients with stages 3-5 CKD. In an interview, 107 participants with the help of a dietician filled out an SFFQ and reviewed a 3-day DR the patients had filled out prior to the interview. Partial Pearson correlation coefficients between SFFQ and 3-day DR were 0.722, 0.619, 0.593, 0.572, 0.450, 0.611 and 0.410 for protein, fat, carbohydrate, fiber, phosphorus, potassium, and calcium, respectively, after adjusting for energy intake. Cross-classification analysis revealed 63.5-83.2% similarity in cross-tool estimated intakes of macronutrients, fiber, phosphorus, potassium, and calcium in the same quartiles or adjacent ones. Bland-Altman plots revealed good agreement between the two tools along different intake levels. In conclusion, the newly developed SFFQ had moderate relative validity in estimating the usual intake of key nutrients related to nutrition management of patients with late-stage CKD, suggesting it can be used to assess dietary intakes in a population with CKD, especially in those residing in an Asian region.

Associations of Physical Activity, Kidney Function, Diet, and Inflammatory Markers in High-Risk Type-2 Diabetes With Early-Stage Chronic Kidney Disease (CKD)

OBJECTIVES Quantitative information and associations of physical activity, kidney function, diet, and inflammation are dearth in high-risk diabetes. Yet could delay type-2 diabetes, late-stage chronic kidney disease (CKD) and could be useful in designing effective interventions. The study aims to quantify the associations of physical activity, kidney function, diet and inflammation in adults with high-risk type-2 diabetes (and early CKD) recruited to a lifestyle education programme.METHODS Baseline, 12-month dietary, accelerometery, and circulating inflammatory markers, Interleukin-6 (IL-6) and C-reactive protein (CRP) data were assessed from 159 (104 male) high-risk diabetes with stage 2 CKD (mean (SD) estimated glomerular filteration rate (eGFR); 77.5(7.6) ml/min/1.73m2, age; 66(6) years, BMI; 31.8(4.2) kg/m2) who were recruited to a lifestyle education programme. Linear regression examined the effects and associations of the outcome measures.RESULTS eGFR decreased by -2.0 (1.7) ml/min/1.73 m2 (P = 0.04) after 12-months, but mean daily steps, moderate to vigorous physical activity (MVPA) levels, intakes of fibre, total and unsaturated fat, and circulating IL-6 and CRP did not change. However, inter-individual responses were highly variable. eGFR correlated positively with baseline IL-6 (r = 0.17, P = 0.02). Unadjusted, there were no associations between change in eGFR (12_0) and change in any of the activity, inflammatory or dietary outcomes. However, the regression models of these outcomes for change in eGFR (12_0) became significant with multiple covariates.CONCLUSION A combination of healthy lifestyle behaviours should be encouraged for a positive effect on future kidney function.

Acceptability of Plant-Based Diets for People with Chronic Kidney Disease: Perspectives of Renal Dietitians

The purpose of this study was to explore the perspective of renal dietitians regarding plant-based diets for chronic kidney disease (CKD) management and evaluate the acceptability of a hypothetical plant-based dietary prescription aiming for the consumption of 30 unique plant foods per week. This study used an exploratory mixed methods design. Forty-six renal dietitians participated in either an online survey (n = 35) or an in-depth interview (n = 11). Dietitians perceived that plant-based diets could address multiple clinical concerns relevant to CKD. Forty percent of survey respondents reported the hypothetical dietary prescription was realistic for people with CKD, 34.3% were unsure, and 25.7% perceived it as unrealistic. Strengths of the hypothetical prescription included shifting the focus to whole foods and using practical resources like recipes. Limited staffing, time, and follow-up opportunities with patients, as well as differing nutrition philosophies were the most commonly reported challenges to implementation; while a supportive multidisciplinary team was identified as an important enabler. To increase patient acceptance of plant-based dietary approaches, education about plant food benefits was recommended, as was implementing small, incremental dietary changes. Successful implementation of plant-based diets is perceived to require frequent patient contact and ongoing education and support by a dietitian. Buy-in from the multidisciplinary team was also considered imperative.

Nutritional Status, Nutritional Phenotypes, and Oral Nutritional Supplement Prescription Patterns Among Patients With Non-Dialysis Chronic Kidney Disease in British Columbia

OBJECTIVES

Management of protein-energy wasting and undernutrition with oral nutritional supplements (ONS) has not been systematically studied in the non-dialysis chronic kidney disease (CKD-ND) population. We aimed to describe nutritional status, identify phenotypes of patients prescribed ONS, and evaluate ONS prescription patterns among CKD-ND patients in British Columbia.

DESIGN AND METHODS

This observational study assessed adult CKD-ND patients who entered multidisciplinary CKD clinics during 2013-2018 in British Columbia. Descriptive statistics were used to describe baseline nutrition and inflammation parameters among patients prescribed ONS versus patients not prescribed ONS within 1 year of clinic entry. Hierarchical clustering method with consensus clustering was applied to identify phenotypes of patients prescribed ONS. Multivariable logistic regression was used to assess the associations between ONS prescription and health region/dietitian full-time equivalents per 1,000 CKD patients.

RESULTS

Of 15,859 CKD-ND patients, 9% of patients entering CKD clinics were prescribed ONS within 1 year of clinic entry, and these patients demonstrated lower baseline estimated glomerular filtration rate, body mass index (BMI), serum albumin, bicarbonate, as well as greater age, serum phosphate, and neutrophil-to-lymphocyte ratio compared with those not receiving ONS. Cluster analysis revealed 5 phenotypes of ONS users: cluster 1 had the highest mean neutrophil-to-lymphocyte ratio; cluster 2 had the lowest mean albumin; cluster 3 had the lowest mean BMI; cluster 4 had the highest mean BMI; and cluster 5 had the lowest mean bicarbonate. There was regional variability in ONS prescription, and an odds ratio for ONS prescription of 1.32 (95% confidence interval 1.16-1.50) for every 1-unit increase in dietitian full-time equivalents per 1,000 patients. Over 3 years of follow-up, overall ONS use among CKD-ND patients remained stable.

CONCLUSIONS

This study demonstrates appropriate prescribing of ONS to patients with suboptimal nutritional status, although regional variation exists. Patients receiving ONS represent a heterogenous group with phenotypes reflecting several clinical and biochemical features of the protein-energy wasting syndrome. These findings will assist with updating ONS policy, planning quality improvement initiatives, and informing dietitian resource allocation.

The dietary intake of chronic kidney disease according to stages: Findings from the Korean National Health and Nutritional Examination Survey

Appropriate dietary adjustment in patients with chronic kidney disease (CKD) is important, and nutritional guidelines recommend different dietary management depending on the CKD stage. However, there is no study, to our knowledge, of the characteristics of dietary intake according to CKD stages. We tried to assess the comparison of nutritional intake according to CKD stages. A cross-sectional study was conducted to reveal the characteristics of dietary intake among patients with CKD based on the Korean National Health and Nutritional Examination Survey between 2011 and 2014. Of 16,878 participants, we classified non-CKD (n = 14,952) and CKD (n = 1,926), which was stratified into five groups (I, II, IIIa, IIIb, and IV–V). We investigated the characteristics of dietary intake, such as energy, water, protein, fat, carbohydrate, sodium, potassium, calcium, and phosphorus, according to stage of CKD. We also explored nutritional intake according to CKD stage among patients with early CKD (stage I and II) and advanced CKD (stage IIIa, IIIb, and IV–V). Intake of majority of nutrients and energy tended to be decreased as CKD progressed. In early CKD stage, intake of energy, water, protein, fat, carbohydrate, potassium, calcium and phosphorus seemed to be statistically significant decreased as CKD progressed. In advanced CKD stage, intake of potassium and calcium seemed to be decreased as CKD progressed, but the intake of energy was about to be lower limit. Appropriate dietary education and CKD recognition are needed to improve nutritional intake depending on the CKD stage.

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.

Nephroprotective activity of Vetiveria zizanioides (L.) Nash supplement in doxorubicin-induced nephrotoxicity model of Wistar rats

The nephroprotective effect of standardized aqueous root extract of Vetiveria zizanioides (L.) Nash (Family: Poaceae) was investigated in doxorubicin-induced (20 mg/kg, ip) experimental nephrotoxicity model of Wistar rats. The freeze-dried aqueous refluxed (4 hr) root extract of V. zizanioides (25, 50; equivalent human therapeutic dose and 100 mg/kg) was administered separately to nephrotoxic Wistar rats (n = 6/group). Supplement of V. zizanioides resulted a dose-dependent reduction in raised serum creatinine, β₂ -microglobulin, and blood urea nitrogen and a subsequent increase in serum total protein and albumin in nephrotoxic rats (p < .05). An attenuation of the doxorubicin-induced features of renal parenchymal injury was observed on H- and E-stained sections of the kidney tissues. Nootkatone, dehydroaromadendrene, isokhusenic acid, α-vetivone, and isolongifolene were identified in the methanol extract of V. zizanioides based on the GC-MS chromatogram analysis. The findings revealed that the supplement of standardized aqueous root extract of V. zizanioides had a significant dose-dependent nephroprotective activity against doxorubicin-induced experimental nephrotoxicity. PRACTICAL APPLICATIONS: Vetiveria zizanioides is a medicinal plant with a variety of therapeutic applications in kidney-related diseases. Apparently, it is used as a food ingredient due to its fresh and elegant scent and potential bioactivities. The aqueous root extract of V. zizanioides exerted relatively high antioxidant potential in vitro, substantiating the health effects of the plant pertaining to kidney diseases as a potential source of dietary antioxidant. The administration of the plant extract resulted in significant nephroprotection against doxorubicin-induced experimental nephrotoxicity revealing the significance of V. zizanioides as a promising dietary supplement in the management of kidney disease.

Dietary Modelling to Explore the Impact of Potassium Chloride Replacement for Sodium in Bread for Adults with Chronic Kidney Disease

Food manufacturers are increasingly substituting potassium chloride (KCl) in food products so as to reduce the sodium chloride content. Bread and bread products are common staple foods in many Western households and are a target for recipe reformulation using KCl. Given that chronic kidney disease (CKD) is a medical condition of global importance that requires dietary potassium restriction in the later stages, we sought to evaluate the impact and safety of varying levels of KCl substitution in bread products. We undertook a secondary analysis of dietary data from the National Nutrition and Physical Activity Survey 2011–2012 for 12,152 participants (154 participants with CKD). The sodium chloride content in bread and bread-based products was substituted with 20%, 30%, and 40% of KCl. The contribution of these alterations in the dietary potassium intake to the total daily potassium intake were then examined. The replacement of sodium in bread with varying amounts of KCl (20%, 30%, and 40%) resulted in one third of people with CKD exceeding the safe limits for dietary potassium consumption (31.8%, 32.6%, and 33%, respectively). KCl substitution in staple foods such as bread and bread products have serious and potentially fatal consequences for people who need to restrict dietary potassium. Improved food labelling is required for consumers to avoid excessive consumption.

Peritoneal Dialysis Guidelines 2019 Part 1 (Position paper of the Japanese Society for Dialysis Therapy)

Approximately 10 years have passed since the Peritoneal Dialysis Guidelines were formulated in 2009. Much evidence has been reported during the succeeding years, which were not taken into consideration in the previous guidelines, e.g., the next peritoneal dialysis PD trial of encapsulating peritoneal sclerosis (EPS) in Japan, the significance of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs), the effects of icodextrin solution, new developments in peritoneal pathology, and a new international recommendation on a proposal for exit-site management. It is essential to incorporate these new developments into the new clinical practice guidelines. Meanwhile, the process of creating such guidelines has changed dramatically worldwide and differs from the process of creating what were “clinical practice guides.” For this revision, we not only conducted systematic reviews using global standard methods but also decided to adopt a two-part structure to create a reference tool, which could be used widely by the society’s members attending a variety of patients. Through a working group consensus, it was decided that Part 1 would present conventional descriptions and Part 2 would pose clinical questions (CQs) in a systematic review format. Thus, Part 1 vastly covers PD that would satisfy the requirements of the members of the Japanese Society for Dialysis Therapy (JSDT). This article is the duplicated publication from the Japanese version of the guidelines and has been reproduced with permission from the JSDT.

Optimizing Diet to Slow CKD Progression

Due to the unique role of the kidney in the metabolism of nutrients, patients with chronic kidney disease (CKD) lose the ability to excrete solutes and maintain homeostasis. Nutrient intake modifications and monitoring of nutritional status in this population becomes critical, since it can affect important health outcomes, including progression to kidney failure, quality of life, morbidity, and mortality. Although there are multiple hemodynamic and metabolic factors involved in the progression and prognosis of CKD, nutritional interventions are a central component of the care of patients with non-dialysis CKD (ND-CKD) and of the prevention of overweight and possible protein energy-wasting. Here, we review the reno-protective effects of diet in adults with ND-CKD stages 3-5, including transplant patients.

Protein energy wasting and long-term outcomes in nondialysis dependent chronic kidney disease

BACKGROUND

Nutritional status and protein energy wasting (PEW) is prevalent in patients with nondialysis-dependent chronic kidney disease (CKD). The relationship between PEW and long-term development of clinically important outcomes remains to be examined.

OBJECTIVES

To investigate the relationships between PEW, as measured by Subjective Global Assessment (SGA 1-7), and progression to important clinical outcomes: mortality and/or kidney failure.

DESIGN

Prospective cohort design.

PARTICIPANTS

One hundred and thirty-nine participants were well-nourished and 37 moderately malnourished patients with CKD 3-5.

MEASUREMENTS

The outcomes were 2, 5, and 10-year progression to kidney failure (dialysis or transplant) or mortality, kidney failure alone, and mortality alone. SGA was determined by a registered renal dietitian. Food frequency questionnaires were used to assess dietary intake. Clinical and laboratory baseline characteristics were collected. Multivariable regression models and Cox models were created to examine the relationship between SGA and outcomes.

RESULTS

PEW was associated with the combined outcome of kidney failure or mortality at 2 (p = 0.003), 5 (p = 0.004), but not at 10 (p = 0.73) years. This relationship was primarily driven by the relationship between PEW and kidney failure. In Cox models, the relationship between PEW and kidney failure remained after adjusting for Kidney Failure Risk Equation scores. The multivariable modeling revealed that PEW remained a statistically significant predictor of the combined outcome and ESKD after adjustment for age, estimated glomerular filtration rate (eGFR), sex, albumin-to-creatinine ratio, diabetes, albumin, and protein intake.

CONCLUSIONS

PEW, determined by the SGA 1-7, is an important prognostic tool. Further research looking at clinically important outcomes are needed to implement nutritional interventions for nondialysis-dependent CKD patients.

Dietary patterns and chronic kidney disease risk: a systematic review and updated meta-analysis of observational studies

BACKGROUND

A number of studies have reported the association between dietary patterns and the risk of chronic kidney disease (CKD), however a consistent perspective hasn't been established to date. Herein, we conducted this systematic review and meta-analysis of observational studies to assess the association between dietary patterns and CKD.

METHODS

MEDLINE, EBSCO and references from eligible studies were searched for relevant articles published up to 9 May 2020 that examined the association of common dietary patterns and CKD. The heterogeneity among studies was assessed by Cochran's Q test and I² methods.

RESULTS

Seventeen eligible studies, involving 149,958 participants, were included in our systematic review and meta-analysis. The highest compared with the lowest category of healthy dietary pattern was significantly associated with a lower risk of CKD (OR=0.69; CI: 0.57, 0.84; P=0.0001). A higher risk of CKD was shown for the highest compared with the lowest categories of Western-type dietary pattern (OR=1.86; CI: 1.21, 2.86; P=0.005). There were evidence of a lower risk of CKD in the highest compared with the lowest categories of light-moderate drinking pattern (OR=0.76; CI: 0.71, 0.81; P< 0.0001) and heavy drinking pattern (OR=0.67; CI: 0.56, 0.80; P< 0.0001).

CONCLUSIONS

The results of this systematic review and meta-analysis show that a healthy dietary pattern and alcohol drinking were associated with lower risk of CKD, whereas a Western-type dietary pattern was associated with higher risk of CKD.

Recent Progress on Lipid Intake and Chronic Kidney Disease

The incidence of chronic kidney disease (CKD) is associated with major abnormalities in circulating lipoproteins and renal lipid metabolism. This article elaborates on the mechanisms of CKD and lipid uptake abnormalities. The viewpoint we supported is that lipid abnormalities directly cause CKD, resulting in forming a vicious cycle. On the theoretical and experiment fronts, this inference has been verified by elaborately elucidating the role of lipid intake and accumulation as well as their influences on CKD. Taken together, these findings suggest that further understanding of lipid metabolism in CKD may lead to novel therapeutic approaches.

Intradialytic Nutrition and Hemodialysis Prescriptions: A Personalized Stepwise Approach

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

Safety and Efficacy of Using Nuts to Improve Bowel Health in Hemodialysis Patients

OBJECTIVE

Constipation is common in patients with end-stage kidney disease. Nondrug strategies to manage constipation are challenging because of dietary potassium, phosphate, and fluid restrictions. Nuts are a high-fiber food but are excluded from the diet because of the high potassium and phosphate content. The aim of this study was to examine the safety and efficacy of using nuts to improve constipation in adults undertaking hemodialysis (HD).

DESIGN AND METHODS

Adult patients undertaking HD were recruited to this nonrandomized, 10-week repeated measures, within-subject, pragmatic clinical trial, conducted in two HD units. The intervention consisted of consumption of 40g of raw almonds daily for four weeks, followed by a two-week washout and four-week control period. The primary safety outcome measures were change in predialysis serum potassium and phosphate levels. The primary efficacy outcome was reduction in constipation, measured using the Bristol Stool Form Scale and Palliative Care Outcome Scale (POS-S) renal symptom score. Secondary outcomes included quality of life, selected uremic toxins, cognition, gut microbiota profile, and symptom burden.

RESULTS

Twenty patients completed the trial (median age: 67 [interquartile range: 57.5-77.8] years, 51% male). After controlling for dialysis adequacy, anuria, dietary intake, bicarbonate, and parathyroid hormone, there were no statistically significant changes in serum potassium (P = 0.21) or phosphate (P = 0.16) associated with daily consumption of almonds. However, statistically significant improvements in constipation were seen at weeks 2, 3, 4, and 10. There were statistically significant improvements in quality of life (P = 0.030), overall symptom burden (P = 0.002), vomiting (P = 0.020), itching (P = 0.006), and skin changes (P = 0.002).

CONCLUSION

Daily consumption of almonds for four weeks was safe, effective, and well tolerated. Improvements in quality of life and symptom burden warrant further research to elucidate potential mechanisms. The findings support the potential reinclusion of foods such as nuts into the diet of patients who underwent HD.

A practical guide for the use of very low calorie diets in adults with chronic kidney disease

Obesity is increasingly common in individuals with chronic kidney disease (CKD). Being overweight or obese is associated with both the development and progression of kidney disease. Lifestyle interventions such as the use of very low-calorie diets (VLCD) are being used increasingly for patients with CKD despite warnings from manufacturers that they should be avoided or used with caution. Whilst these diets are effective and can induce rapid weight loss and suppress appetite, their use in patients with chronic and end stage kidney disease is more complex than in the general population. VLCD use in adults with kidney disease requires a more nuanced approach to prescription and closer monitoring for unintended side effects. This review describes the indications and clinical management of patients with CKD undertaking a very low-calorie diet and provides practical guidance regarding how to manage a VLCD, particularly for the latter stages of CKD.

Association Between Dietary Patterns and Kidney Function in Patients With Chronic Kidney Disease: A Cross-Sectional Analysis of the German Chronic Kidney Disease Study

OBJECTIVE

In the general population, "healthy" dietary patterns are associated with improved health outcomes, but data on associations between observance of specific dietary patterns and kidney function in patients with chronic kidney disease (CKD) are sparse.

METHODS

Dietary intake was evaluated using food frequency questionnaires in patients with moderately severe CKD under nephrology care enrolled into the observational multicenter German CKD study. The Dietary Approaches to Stop Hypertension (DASH) diet score, Mediterranean diet score, and German Food Pyramid Index (GFPI) were calculated and their association with estimated glomerular filtration rate (eGFR) and albuminuria was assessed by multivariable linear regression analysis, adjusted for gender, age, body mass index, energy intake, smoking status, alcohol intake, education, high-density lipoprotein-cholesterol (HDL- cholesterol), low-density lipoprotein-cholesterol (LDL-cholesterol), hypertension, and diabetes mellitus.

RESULTS

A total of 2,813 patients (41% women; age 60.1 ± 11.6 years) were included in the analysis. High DASH diet score and GFPI were associated with lower systolic blood pressure and lower intake of antihypertensive medication, higher HDL, and lower uric acid levels. Mediterranean-style diet was associated with lower prevalence of diabetes mellitus. Higher DASH and Mediterranean diet scores were associated with higher eGFR (β-coefficient = 1.226, P < .001; β-coefficient = 0.932, P = .007, respectively). In contrast, GFPI was not associated with eGFR. For the individual components of the dietary patterns, higher intake of nuts and legumes, cereals, fish, and polyunsaturated fats was associated with higher eGFR and higher intake of dairy, composed of low- and whole-fat dairy, was associated with lower eGFR. No association was found between dietary patterns and albuminuria.

CONCLUSION

Higher observance of the DASH or Mediterranean diet, but not German food pyramid recommendations, was associated with higher eGFR among patients with CKD. Improving dietary habits may offer an opportunity to better control comorbidities and kidney function decline in patients with CKD.

Education and Protein Supplementation Improve Nutritional Biomarkers among Hypoalbuminemic Peritoneal Dialysis Patients: A Quasi-Experimental Design

Protein-energy wasting is prevalent in peritoneal dialysis patients, which causes a heavy burden for individuals and healthcare systems. We aimed to investigate the effect of nutritional education, and/or protein supplementation on nutritional biomarkers in hypoalbuminemic peritoneal dialysis patients. A quasi-experimental study was conducted in two dialysis centers at Taipei Tzu Chi Hospital and Shin Kong Wu Ho-Su Memorial Hospital. Patients were allocated in three groups including control (n = 12), milk protein (n = 21) and soy protein (n = 20). All patients received dietary guidelines from dietitians and completed 3-day dietary records during monthly visits for consecutive three months. Nutrients were analyzed using Nutritionist Professional software. Blood urea nitrogen (BUN), creatinine, albumin, total protein, hemoglobin, serum calcium, phosphorus, sodium, and potassium were assessed monthly. Total cholesterol and triglycerides were measured every three months. After three-month intervention, protein intake (percent of total calories), and serum albumin were significantly increased in three groups. Protein, phosphorus intake, and BUN were increased in two intervention groups. Total serum protein increased in control and milk protein groups, and creatinine increased the control group. Serum phosphorus was not significantly changed. Nutritional education alone, or combined with protein supplementation, significantly improve protein intake, and nutritional status by increasing serum albumin, but not serum phosphorus in hypoalbuminemic peritoneal dialysis patients.

Is Health Literacy of Dialyzed Patients Related to Their Adherence to Dietary and Fluid Intake Recommendations?

Non-adherence to dietary and fluid intake recommendations (NADFIR) is an important factor for the effective treatment of dialyzed patients and may be hindered by low health literacy (HL). Therefore, we assessed whether low HL of dialyzed patients is associated with their NADFIR. We performed a multicentric cross-sectional study in 20 dialysis clinics in Slovakia (n = 452; response rate: 70.1%; mean age = 63.6 years; males: 60.7%). We assessed the association between nine domains of HL and non-adherence (high serum potassium, high serum phosphate, relative overhydration, and self-reported NADFIR) using general linear models adjusted for age and gender. Moreover, we assessed the moderation by socioeconomic status (SES). We found higher NADFIR among patients with less sufficient information for health management (high serum phosphate level; odds ratio (OR): 0.77; 95% confidence interval (CI): 0.63-0.94), with a lower ability to actively manage their health (self-reported diet non-adherence; OR: 0.74; 95% CI: 0.62-0.89), and those less able to actively engage with healthcare providers (overhydrated; OR: 0.78; 95% CI: 0.65-0.94). Moreover, SES modified this relation. Low HL affects the adherence of dialyzed patients. This shows a need to support patients with low HL and to train healthcare providers to work with these patients, taking into account their SES.

Dietary Patterns and Mortality in a Multinational Cohort of Adults Receiving Hemodialysis

RATIONALE & OBJECTIVE

Clinical practice guidelines for dietary intake in hemodialysis focus on individual nutrients. Little is known about associations of dietary patterns with survival. We evaluated the associations of dietary patterns with cardiovascular and all-cause mortality among adults treated by hemodialysis.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

8,110 of 9,757 consecutive adults on hemodialysis (January 2014 to June 2017) treated in a multinational private dialysis network and with analyzable dietary data.

EXPOSURES

Data-driven dietary patterns based on the GA²LEN food frequency questionnaire. Participants received a score for each identified pattern, with higher scores indicating closer resemblance of their diet to the identified pattern. Quartiles of standardized pattern scores were used as primary exposures.

OUTCOMES

Cardiovascular and all-cause mortality.

ANALYTICAL APPROACH

Principal components analysis with varimax rotation to identify common dietary patterns. Adjusted proportional hazards regression analyses with country as a random effect to estimate the associations between dietary pattern scores and mortality. Associations were expressed as adjusted HRs with 95% CIs, using the lowest quartile score as reference.

RESULTS

During a median follow-up of 2.7 years (18,666 person-years), there were 2,087 deaths (958 cardiovascular). 2 dietary patterns, "fruit and vegetable" and "Western," were identified. For the fruit and vegetable dietary pattern score, adjusted HRs, in ascending quartiles, were 0.94 (95% CI, 0.76-1.15), 0.83 (95% CI, 0.66-1.06), and 0.91 (95% CI, 0.69-1.21) for cardiovascular mortality and 0.95 (95% CI, 0.83-1.09), 0.84 (95% CI, 0.71-0.99), and 0.87 (95% CI, 0.72-1.05) for all-cause mortality. For the Western dietary pattern score, the corresponding estimates were 1.10 (95% CI, 0.90-1.35), 1.11 (95% CI, 0.87-1.41), and 1.09 (95% CI, 0.80-1.49) for cardiovascular mortality and 1.01 (95% CI, 0.88-1.16), 1.00 (95% CI, 0.85-1.18), and 1.14 (95% CI, 0.93-1.41) for all-cause mortality.

LIMITATIONS

Self-reported food frequency questionnaire, data-driven approach.

CONCLUSIONS

These findings did not confirm an association between mortality among patients receiving long-term hemodialysis and the extent to which dietary patterns were either high in fruit and vegetables or consistent with a Western diet.

Targeted, structured text messaging to improve dietary and lifestyle behaviours for people on maintenance haemodialysis (KIDNEYTEXT): study protocol for a randomised controlled trial

INTRODUCTION

Managing nutrition is critical for reducing morbidity and mortality in patients on haemodialysis but adherence to the complex dietary restrictions remains problematic. Innovative interventions to enhance the delivery of nutritional care are needed. The aim of this phase II trial is to evaluate the feasibility and effectiveness of a targeted mobile phone text messaging system to improve dietary and lifestyle behaviours in patients on long-term haemodialysis.

METHODS AND ANALYSIS

Single-blinded randomised controlled trial with 6 months of follow-up in 130 patients on haemodialysis who will be randomised to either standard care or KIDNEYTEXT. The KIDNEYTEXT intervention group will receive three text messages per week for 6 months. The text messages provide customised dietary information and advice based on renal dietary guidelines and general healthy eating dietary guidelines, and motivation and support to improve behaviours. The primary outcome is feasibility including recruitment rate, drop-out rate, adherence to renal dietary recommendations, participant satisfaction and a process evaluation using semistructured interviews with a subset of purposively sampled participants. Secondary and exploratory outcomes include a range of clinical and behavioural outcomes and a healthcare utilisation cost analysis will be undertaken.

ETHICS AND DISSEMINATION

The study has been approved by the Western Sydney Local Health District Human Research Ethics Committee-Westmead. Results will be presented at scientific meetings and published in peer-reviewed publications.

TRIAL REGISTRATION NUMBER

ACTRN12617001084370; Pre-results.

Patients' Experiences and Perspectives of Telehealth Coaching with a Dietitian to Improve Diet Quality in Chronic Kidney Disease: A Qualitative Interview Study

BACKGROUND

Dietary behavior change interventions for the self-management of chronic kidney disease (CKD) have the potential to slow disease progression and reduce metabolic complications. Telehealth-delivered dietary interventions may assist in the self-management of CKD, although their acceptability by patients is unknown.

OBJECTIVE

This study aims to describe the acceptability and experiences of a telehealth coaching intervention that utilized telephone calls and tailored text messages to improve diet quality in patients with stage 3 to 4 CKD.

DESIGN

Semistructured interview study of adults with CKD.

PARTICIPANTS/SETTING

Adults with stage 3 to 4 CKD (n=21) aged 28 to 78 (mean 62) years, who completed a 12-week telehealth-delivered dietary intervention in Queensland, Australia, were interviewed from March to July 2017.

DATA ANALYSIS

Interviews were transcribed verbatim and analyzed thematically.

RESULTS

Five themes were identified: valuing relationships (receiving tangible and perceptible support, building trust and rapport remotely, motivated by accountability, readily responding to a personalized approach, reassured by health professional expertise); appreciating convenience (integrating easily into lifestyle, talking comfortably in a familiar environment, minimizing travel and wait time burden); empowered with actionable knowledge (comprehending diet-disease mechanisms, practical problem solving for sustainable dietary behavior); increasing diet consciousness (learning from recurrent feedback, prompted by reiteration of messages); making sense of complexity (contextualizing and prioritizing comorbidities, gaining confidence to make dietary decisions, setting and achieving realistic goals).

CONCLUSIONS

Among adults with stage 3 to 4 CKD, individualized telehealth coaching for improving diet quality was convenient for patients, and they felt supported and empowered to navigate recommendations and prioritize dietary behavior changes. Telehealth-delivered dietary interventions appear to be well accepted by patients as a way of providing regular, tailored contact with a health professional to support dietary management in CKD.

Weight management strategies for those with chronic kidney disease: A consensus report from the Asia Pacific Society of Nephrology and Australia and New Zealand Society of Nephrology 2016 renal dietitians meeting

AIM

The aim of the present study was to develop a consensus report to guide dietetic management of overweight or obese individuals with chronic kidney disease (CKD).

METHODS

Six statements relating to weight management in CKD guided a comprehensive review of the literature. A summary of the evidence was then presented at the renal nutrition meeting of the 2016 Asia Pacific Society of Nephrology and Australia and New Zealand Society of Nephrology. Majority agreement was defined as group agreement on a statement of between 50-74%, and consensus was considered ≥75% agreement. The recommendations were developed via a mini Delphi process.

RESULTS

Two statements achieved group consensus: the current guidelines used by dietitians to estimate energy requirements for overweight and obese people with CKD are not relevant and weight loss medications may be unsafe or ineffective in isolation for those with CKD. One statement achieved group agreement: Meal replacement formulas are safe and efficacious in those with CKD. No agreement was achieved on the statements of whether there is strong evidence of benefit for weight loss prior to kidney transplantation; whether traditional weight loss strategies can be used in those with CKD and if bariatric surgery in those with end stage kidney disease is feasible and effective.

CONCLUSION

There is a limited evidence base to guide the dietetic management of overweight and obese individuals with CKD. Medical or surgical strategies to facilitate weight loss are not recommended in isolation and require a multidisciplinary approach with the involvement of a skilled renal dietitian.

Fruit and Vegetable Intake and Mortality in Adults undergoing Maintenance Hemodialysis

BACKGROUND AND OBJECTIVES

Higher fruit and vegetable intake is associated with lower cardiovascular and all-cause mortality in the general population. It is unclear whether this association occurs in patients on hemodialysis, in whom high fruit and vegetable intake is generally discouraged because of a potential risk of hyperkalemia. We aimed to evaluate the association between fruit and vegetable intake and mortality in hemodialysis.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Fruit and vegetable intake was ascertained by the Global Allergy and Asthma European Network food frequency questionnaire within the Dietary Intake, Death and Hospitalization in Adults with ESKD Treated with Hemodialysis study, a multinational cohort study of 9757 adults on hemodialysis, of whom 8078 (83%) had analyzable dietary data. Adjusted Cox regression analyses clustered by country were conducted to evaluate the association between tertiles of fruit and vegetable intake with all-cause, cardiovascular, and noncardiovascular mortality. Estimates were calculated as hazard ratios with 95% confidence intervals (95% CIs).

RESULTS

During a median follow up of 2.7 years (18,586 person-years), there were 2082 deaths (954 cardiovascular). The median (interquartile range) number of servings of fruit and vegetables was 8 (4-14) per week; only 4% of the study population consumed at least four servings per day as recommended in the general population. Compared with the lowest tertile of servings per week (0-5.5, median 2), the adjusted hazard ratios for the middle (5.6-10, median 8) and highest (>10, median 17) tertiles were 0.90 (95% CI, 0.81 to 1.00) and 0.80 (95% CI, 0.71 to 0.91) for all-cause mortality, 0.88 (95% CI, 0.76 to 1.02) and 0.77 (95% CI, 0.66 to 0.91) for noncardiovascular mortality and 0.95 (95% CI, 0.81 to 1.11) and 0.84 (95% CI, 0.70 to 1.00) for cardiovascular mortality, respectively.

CONCLUSIONS

Fruit and vegetable intake in the hemodialysis population is low and a higher consumption is associated with lower all-cause and noncardiovascular death.

Feasibility and acceptability of telehealth coaching to promote healthy eating in chronic kidney disease: a mixed-methods process evaluation

OBJECTIVE

To evaluate the feasibility and acceptability of a personalised telehealth intervention to support dietary self-management in adults with stage 3-4 chronic kidney disease (CKD).

DESIGN

Mixed-methods process evaluation embedded in a randomised controlled trial.

PARTICIPANTS

People with stage 3-4 CKD (estimated glomerular filtration rate [eGFR]15-60 mL/min/1.73 m²).

SETTING

Participants were recruited from three hospitals in Australia and completed the intervention in ambulatory community settings.

INTERVENTION

The intervention group received one telephone call per fortnight and 2-8 tailored text messages for 3 months, and then 4-12 tailored text messages for 3 months without telephone calls. The control group received usual care for 3 months then non-tailored education-only text messages for 3 months.

MAIN OUTCOME MEASURES

Feasibility (recruitment, non-participation and retention rates, intervention fidelity and participant adherence) and acceptability (questionnaire and semistructured interviews).

STATISTICAL ANALYSES PERFORMED

Descriptive statistics and qualitative content analysis.

RESULTS

Overall, 80/230 (35%) eligible patients who were approached consented to participate (mean±SD age 61.5±12.6 years). Retention was 93% and 98% in the intervention and control groups, respectively, and 96% of all planned intervention calls were completed. All participants in the intervention arm identified the tailored text messages as useful in supporting dietary self-management. In the control group, 27 (69%) reported the non-tailored text messages were useful in supporting change. Intervention group participants reported that the telehealth programme delivery methods were practical and able to be integrated into their lifestyle. Participants viewed the intervention as an acceptable, personalised alternative to face-face clinic consultations, and were satisfied with the frequency of contact.

CONCLUSIONS

This telehealth-delivered dietary coaching programme is an acceptable intervention which appears feasible for supporting dietary self-management in stage 3-4 CKD. A larger-scale randomised controlled trial is needed to evaluate the efficacy of the coaching programme on clinical and patient-reported outcomes.

TRIAL REGISTRATION NUMBER

ACTRN12616001212448; Results.

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

Background/objective

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

Methods

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

Results

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

Conclusions

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

Should We Recommend Renal Diet-Related Apps to Our Patients? An Evaluation of the Quality and Health Literacy Demand of Renal Diet-Related Mobile Applications

OBJECTIVE

Mobile phone applications (apps) are increasingly being used by patients with chronic kidney disease (CKD). We sought to describe the main purpose of commonly available renal diet apps and to quantify the accuracy of information, technical quality, and health literacy demand of renal diet apps.

DESIGN

The design was content analysis. All eligible renal diet apps in the Australian Apple App Store, Google Play, Windows Phone, and Blackberry App World were evaluated.

SUBJECTS

Eligible apps were in English and were related to kidney disease in humans (of any type or stage). Exclusion criteria included apps which were prohibited because of password protection.

MAIN OUTCOME MEASURE

Renal diet information in the apps was compared with evidence-based guidelines for the management of kidney disease to quantify information accuracy. App information was evaluated using the Silberg Scale. Technical quality and health literacy demand were evaluated using the Mobile Application Rating Scale.

RESULTS

A total of 21 apps were eligible for evaluation. The main purpose of these apps was to provide food and nutrition information (57.1%) or for educative purposes for CKD patients (38.1%). Only 47.6% (10/21) of apps contained accurate evidence-based information. Overall, app technical quality was considered acceptable (mean Mobile Application Rating Scale score 3.19 ± 0.35 out of 5), with 80.9% of apps scoring acceptable or greater for app technical quality. Scores for health literacy demand also indicated that most apps (15/21, 71.4%) were acceptable.

CONCLUSIONS

A range of apps currently exist that may provide individuals with CKD with useful food and nutrition information or increase their knowledge of the renal diet. These apps are also mainly of acceptable technical quality and health literacy demand. However, caution is required when using renal diet apps because more than half of the apps evaluated were not accurate and evidence based.

Effects of Low-Protein Diet on lipid and anthropometric profiles of patients with chronic kidney disease on conservative management

INTRODUCTION

Chronic Kidney disease (CKD) patients have a high prevalence of cardiovascular mortality, and among the risk factors are dyslipidemia and obesity, common findings in the early stages of CKD. The aim of this study was to evaluate the effects of low protein diet (LPD) on the lipid and anthropometric profile in non-dialysis CKD patients.

METHODS

Forty CKD patients were studied (20 men, 62.7 ± 15.2 years, glomerular filtration rate (GFR) 26.16 ± 9.4 mL/min/1.73m2). LPD (0.6g/kg/d) was prescribed for six months and, biochemical and anthropometric parameters like body mass index (BMI), waist circumference and body fat mass (assessed by dual X-ray absorptiometry - DXA) were evaluated before and after six months with LPD.

RESULTS

After six months of nutritional intervention, patients presented reduction on BMI (from 28.1 ± 5.6 to 27.0 ± 5.3 Kg/m2, p = 0.001), total cholesterol (from 199.7 ± 57.1 to 176.0 ± 43.6mg/dL, p = 0.0001), LDL (from 116.2 ± 48.1 to 97.4 ± 39.1 mg/dL, p = 0,001) and uric acid (from 6.8 ± 1.4 to 6.2 ± 1.3 mg/dL, p = 0.004). In addition, GFR values were increased from 26.2 ± 9.5 to 28.9 ± 12.7mL/min (p = 0.02). The energy, proteins, cholesterol and fiber intake were reduced significantly.

CONCLUSION

LPD prescribe to non-dialysis CKD patients for six months was able to improve some cardiovascular risk factors as overweight and plasma lipid profile, suggesting that LPD can be also an important tool for protection against cardiovascular diseases in these patients.

The Association of Mediterranean and DASH Diets with Mortality in Adults on Hemodialysis: The DIET-HD Multinational Cohort Study

Background Mediterranean and Dietary Approaches to Stop Hypertension (DASH) diets associate with lower cardiovascular and all-cause mortality in the general population, but the benefits for patients on hemodialysis are uncertain.Methods Mediterranean and DASH diet scores were derived from the GA²LEN Food Frequency Questionnaire within the DIET-HD Study, a multinational cohort study of 9757 adults on hemodialysis. We conducted adjusted Cox regression analyses clustered by country to evaluate the association between diet score tertiles and all-cause and cardiovascular mortality (the lowest tertile was the reference category).Results During the median 2.7-year follow-up, 2087 deaths (829 cardiovascular deaths) occurred. The adjusted hazard ratios (95% confidence intervals) for the middle and highest Mediterranean diet score tertiles were 1.20 (1.01 to 1.41) and 1.14 (0.90 to 1.43), respectively, for cardiovascular mortality and 1.10 (0.99 to 1.22) and 1.01 (0.88 to 1.17), respectively, for all-cause mortality. Corresponding estimates for the same DASH diet score tertiles were 1.01 (0.85 to 1.21) and 1.19 (0.99 to 1.43), respectively, for cardiovascular mortality and 1.03 (0.92 to 1.15) and 1.00 (0.89 to 1.12), respectively, for all-cause mortality. The association between DASH diet score and all-cause death was modified by age (P=0.03); adjusted hazard ratios for the middle and highest DASH diet score tertiles were 1.02 (0.81 to 1.29) and 0.70 (0.53 to 0.94), respectively, for younger patients (≤60 years old) and 1.05 (0.93 to 1.19) and 1.08 (0.95 to 1.23), respectively, for older patients.Conclusions Mediterranean and DASH diets did not associate with cardiovascular or total mortality in hemodialysis.

Dietary Sodium and Other Nutrient Intakes among Patients Undergoing Hemodialysis in New Zealand

This study describes baseline intakes of sodium and other nutrients in a multi-ethnic sample of hemodialysis patients in New Zealand participating in the SoLID Trial between May/2013 to May/2016. Baseline 3-day weighed food record collections were analyzed using Foodworks 8 Professional food composition database, supplemented by other sources of nutrient information. Intakes of dietary sodium and other nutrients were compared with relevant guidelines and clinical recommendations. Eighty-five participants completed a 3-day weighed food record. The mean (SD) sodium intake was 2502 (957) mg/day at and more than half of the participants exceeded recommended intake levels. Sodium intake was positively associated with energy intake. Only 5% of participants met the recommended calorie density; nine percent of participants ate the recommended minimum of 1.2 g/kg of protein per day; 68% of participants were consuming inadequate fiber at baseline. A high proportion of dialysis patients in SoLID Trial did not meet current renal-specific dietary recommendations. The data show excess sodium intake. It is also evident that there was poor adherence to dietary guidelines for a range of other nutrients. A total diet approach is needed to lower sodium intake and improve total diet quality among hemodialysis patients in New Zealand.

DIETOS: A dietary recommender system for chronic diseases monitoring and management

BACKGROUND AND OBJECTIVE

Use of mobile and web-based applications for diet and weight management is currently increasing. However, the impact of known apps on clinical outcomes is not well-characterized so far. Moreover, availability of food recommender systems providing high quality nutritional advices to both healthy and diet-related chronic diseases users is very limited. In addition, the potentiality of nutraceutical properties of typical regional foods for improving app utility has not been exerted to this end. We present DIETOS, a recommender system for the adaptive delivery of nutrition contents to improve the quality of life of both healthy subjects and patients with diet-related chronic diseases. DIETOS provides highly specialized nutritional advices in different health conditions.

METHODS

DIETOS was projected to provide users with health profile and individual nutritional recommendation. Health profiling was based on user answers to dynamic real-time medical questionnaires. Furthermore, DIETOS contains catalogs of typical foods from Calabria, a southern Italian region. Several Calabrian foods have been inserted because of their nutraceutical properties widely reported in several quality studies. DIETOS includes some well known methods for user profiling (overlay profiling) and content adaptation (content selection) coming from general purpose adaptive web systems.

RESULTS

DIETOS has been validated for usability for both patients and specialists and for assessing the correctness of the profiling and recommendation, by enrolling 20 chronic kidney disease (CKD) patients at the Department of Nephrology and Dialysis, University Hospital, Catanzaro (Italy) and 20 age-matched healthy controls. Recruited subjects were invited to register to DIETOS and answer to medical questions to determine their health status. Based on our results, DIETOS has high specificity and sensitivity, allowing to determine a medical-controlled user's health profile and to perform a fine-grained recommendation that is better adapted to each user health status. The current version of DIETOS, available online at http://www.easyanalysis.it/dietos is not intended to be used by general users, but only for review purpose.

CONCLUSIONS

DIETOS is a novel food recommender system for healthy people and individuals affected by diet-related chronic diseases. The proposed system builds a users health profile and, accordingly, provides individualized nutritional recommendations, also with attention to food geographical origin.

An integrative review of the methodology and findings regarding dietary adherence in end stage kidney disease

BACKGROUND

Dietary modification is an important component of the management of end stage kidney disease (ESKD). The diet for ESKD involves modifying energy and protein intake, and altering sodium, phosphate, potassium and fluid intake. There have been no comprehensive reviews to date on this topic. The aims of this integrative review were to (i) describe the methods used to measure dietary adherence (ii) determine the rate of dietary adherence and (iii) describe factors associated with dietary adherence in ESKD.

METHODS

The Web of Science and Scopus databases were searched using the search terms 'adherence' and 'end stage kidney disease'. Of the 787 potentially eligible papers retrieved, 60 papers of 24,743 patients were included in this review. Of these papers, 44 reported the rate of dietary adherence and 44 papers described factors associated with adherence.

RESULTS

Most of the evidence regarding dietary adherence is derived from studies of hemodialysis patients (72% of patients). The most common method of measuring dietary adherence in ESKD was subjective techniques (e.g. food diaries or adherence questionnaires). This was followed by indirect methods (e.g. serum potassium, phosphate or interdialytic weight gain). The weighted mean adherence rate to ESKD dietary recommendations was 31.5% and 68.5% for fluid recommendations. Adherence to protein, sodium, phosphate, and potassium recommendations were highly variable due to differences in measurement methods used, and were often derived from a limited evidence base. Socioeconomic status, age, social support and self-efficacy were associated with dietary adherence. However, factors such as taste, the impact of the diet on social eating occasions; and dietetic staffing also appear to play a role in dietary adherence.

CONCLUSION

Dietary adherence rates in people with ESKD are suboptimal. Further research is required on dietary adherence in patients with ESKD from different social, educational, economic and ethnic groups. This research may identify other factors which may impact upon adherence, and could be used to inform the design of future strategies to improve dietary adherence. Future research that reports not just the rate of adherence to individual components of the nutrient prescription but also the overall quality of the diet would be useful.

Diet quality in patients with end-stage kidney disease undergoing dialysis

BACKGROUND

People on haemodialysis (HD) are at risk of consuming a poor quality diet. This includes inadequate intake of omega-3 long chain polyunsaturated fatty acids (n-3 LCPUFA).

OBJECTIVE

This study aims to investigate diet quality, with a particular focus on n-3 LCPUFA intake, in a population of incentre HD patients.

DESIGN

Dietary intake was measured using three 24 hour recalls; the Polyunsaturated food frequency questionnaire (PUFA FFQ) and the Total Diet Score (TDS). Dietary intake was also compared to evidence based practice guidelines (EBPG). Nutritional status was assessed using the Patient Generated Subjective Global Assessment (PG SGA).

SUBJECTS

A total of 32 dialysis patients were recruited, from two regional HD centres in New South Wales, Australia.

MAIN OUTCOME MEASURE

Diet quality was the main outcome measure.

RESULTS

Diet quality of study participants was poor, with the majority not meeting the EBPG for energy, protein and potassium. All participants exceeded the recommended amount of saturated fat. The mean TDS of the dialysis cohort was 10.2, which was significantly higher than the TDS of 9.3 of a healthy disease free cohort (p < 0.05). Positive correlations were found between TDS and LC omega-3 intake (r = 0.392) and TDS and total omega-6 intake (r = 0.363). Only 22% of participants met the suggested dietary target for n-3 LCPUFA intake.

CONCLUSION

Dialysis patients in this study had suboptimal diet quality. Improvements are required for better adherence to the EBPG. Increased consumption of n-3 LCPUFA fatty acids may also be of benefit.

Validity and reproducibility of a short food frequency questionnaire among patients with chronic kidney disease

BACKGROUND

A balanced diet is essential to slowing the progression of chronic kidney disease (CKD) and managing the symptoms. Currently, no tool is available to easily and quickly assess energy and macronutrient intake in patients with non end-stage CKD. We aimed to develop and evaluate the validity and reproducibility of a new short 49-item food frequency questionnaire (SFFQ) adapted to patients with CKD.

METHODS

The CKD-REIN study is a prospective cohort that enrolled 3033 patients with moderate or advanced CKD from a national sample of nephrology clinics. A sub-sample of 201 patients completed the SFFQ twice, at a one-year interval and were included in the reproducibility study. During this interval, 127 patients also completed six 24-h recalls and were included in the validity study. Main nutrient and dietary intakes were computed. Validity was evaluated by calculating crude, energy-adjusted and de-attenuated correlation coefficients (CC) between FFQ and the mean of the 24-h recall results. Bland-Altman plots were performed and cross-classification into quintiles of consumption of each nutrient and food group was computed. Reproducibility between the two SFFQs was evaluated by intraclass CC (ICC).

RESULTS

Regarding validity, CC ranged from 0.05 to 0.79 (unadjusted CC, median: 0.40) and 0.10 to 0.59 (de-attenuated CC, median: 0.35) for food group and nutrient intakes, respectively. Five of the most important nutrients of interest in CKD, i.e. protein, calcium, phosphorus, potassium, and sodium had de-attenuated CC of 0.46, 0.43, 0.39, 0.32, and 0.12, respectively. The median of classification into the same or adjacent quintiles was 68% and 65% for food and nutrient intakes, respectively, and ranged from 63% to 69% for the five nutrients mentioned before. Bland-Altman plots showed good agreement across the range of intakes. ICC ranged from 0.18 to 0.66 (median: 0.46).

CONCLUSIONS

The CKD-REIN SFFQ showed acceptable validity and reproducibility in a sample of patients with CKD, notably for CKD nutrients of importance. It can now be used in large-scale epidemiological studies to easily assess the relations between diet and CKD outcomes as well as in clinical routine. It may also serve as a basis for the development of FFQs in international CKD cohort networks.

Effectiveness of educational or behavioral interventions on adherence to phosphate control in adults receiving hemodialysis: a systematic review

BACKGROUND

People with end-stage kidney disease (ESKD) develop impaired excretion of phosphate. Hyperphosphatemia develops in ESKD as a result of the kidney's reduced ability to excrete ingested phosphate load and is characterized by high bone turnover and increased musculoskeletal morbidity including bone pain and muscle weakness. Increased serum phosphate levels are also associated with cardiovascular disease and associated mortality. These effects are significant considering that cardiovascular disease is the leading cause of death in ESKD, making phosphate control a crucial treatment goal.

OBJECTIVES

To determine the effectiveness of education or behavioral interventions on adherence to phosphate control in adults with ESKD receiving hemodialysis (HD).

INCLUSION CRITERIA TYPES OF PARTICIPANTS

Adults aged over 18 years with ESKD undergoing HD, attending dialysis facilities regardless of frequency and duration of treatment sessions per week. Studies with participants receiving hemodiafiltration were excluded.

TYPES OF INTERVENTION(S)/PHENOMENA OF INTEREST

All types of educational and behavioral interventions aimed at improving adherence to dietary phosphate restriction, phosphate binder medication and HD.

TYPES OF STUDIES

Randomized controlled trials (RCTs), non-RCTs, before and after and cohort studies.

OUTCOMES

Outcome measures included serum phosphate levels, patient knowledge and adherence to phosphate control methods, chronic kidney disease (CKD) self-management behavior and perceived self-efficacy for CKD related to phosphate control.

SEARCH STRATEGY

A search was conducted in CINAHL, MEDLINE, The Cochrane Library, Embase, Web of Science, PsycINFO and ProQuest Dissertations and Theses Global to find published studies between January 2005 and December 2015.

METHODOLOGICAL QUALITY

Risk of bias was assessed by three reviewers prior to inclusion in the review using standardized critical appraisal instruments from the Joanna Briggs Institute Meta-Analysis of Statistics Assessment and Review Instrument (JBI-MAStARI).

DATA EXTRACTION

Data were extracted using the standardized data extraction tool from JBI-MAStARI.

DATA SYNTHESIS

Data were pooled using JBI software. Mean differences (95% confidence interval [CI]) and effect size estimates were calculated for continuous outcomes. Meta-analysis using a random-effects model was performed for serum phosphate levels, and where the findings could not be pooled using meta-analysis, results have been presented in a narrative form. Standard GRADE (Grading of Recommendations Assessment, Development and Evaluation) evidence assessment of outcomes has been reported.

RESULTS

A total of 18 studies were included in the review: seven studies focused on dietary phosphate, four studies focused on medications (phosphate binders) and six studies focused on dietary phosphate and medications. Only one study taught patients about diet, medications and HD to control phosphate. Sixteen studies showed significant improvements in phosphate levels. Meta-analysis of eight RCTs favored educational or behavioral interventions over standard care for serum phosphate control, with a weighted mean reduction of -0.23 mmol/l (95% CI -0.37, -0.08) in treatment groups.

CONCLUSION

Overall, educational or behavioral interventions increase adherence to phosphate control. Studies in this systematic review revealed improved outcomes on serum phosphate levels, patient knowledge and adherence to phosphate control methods, CKD self-management behavior and perceived self-efficacy for CKD related to phosphate control. However, there is a lack of sufficient data on how some of the studies implemented their interventions, suggesting that further research is required. Successful strategies that improve and optimize long-term adherence to phosphate control still need to be formulated.

Stirring the Pot: Can Dietary Modification Alleviate the Burden of CKD?

Diet is one of the largest modifiable risk factors for chronic kidney disease (CKD)-related death and disability. CKD is largely a progressive disease; however, it is increasingly appreciated that hallmarks of chronic kidney disease such as albuminuria can regress over time. The factors driving albuminuria resolution remain elusive. Since albuminuria is a strong risk factor for GFR loss, modifiable lifestyle factors that lead to an improvement in albuminuria would likely reduce the burden of CKD in high-risk individuals, such as patients with diabetes. Dietary therapy such as protein and sodium restriction has historically been used in the management of CKD. Evidence is emerging to indicate that other nutrients may influence kidney health, either through metabolic or haemodynamic pathways or via the modification of gut homeostasis. This review focuses on the role of diet in the pathogenesis and progression of CKD and discusses the latest findings related to the mechanisms of diet-induced kidney disease. It is possible that optimizing diet quality or restricting dietary intake could be harnessed as an adjunct therapy for CKD prevention or progression in susceptible individuals, thereby reducing the burden of CKD.