Low protein diets in patients with chronic kidney disease: a bridge between mainstream and complementary-alternative medicines?

Association of carbohydrate intake from different sources with all-cause and cardiovascular mortality among chronic kidney disease populations: assessment of 1999-2018 National Health and Nutrition Examination Survey participation

This study analysed the data from the NHANES (1999-2018) to examine how different sources of carbohydrate intake affected the all-cause and cardiovascular mortality of 11,302 chronic kidney disease (CKD) patients. The data were adjusted for other factors using various methods. The results showed that CKD patients (stages 1-2 and 3-5) who consumed more carbohydrates from whole grains, fruits, vegetables and less carbohydrates from fruit juice or sauces had lower mortality rates. Replacing fat intake with carbohydrates from whole grains (HR = 0.86[0.78-0.95]), fruits (raw) (HR = 0.79[0.70-0.88]) and non-starchy vegetables (HR = 0.82[0.70-0.96]), but not protein intake, was linked to lower all-cause mortality. The fibre content in carbohydrates might partly account for the benefits of selected carbohydrate intake. This study provided practical recommendations for optimising the carbohydrate sources in CKD patients.

Personalized Medicine in Kidney Disease

The Special Issue "Personalized Medicine in Kidney Disease" is focused on the importance of customized medicine in nephrology as it represents one of the main characteristics of successful therapeutic results [...].

Nutrition in Conservative Kidney Management: From Evidence to Practice

Conservative kidney management (CKM) is a treatment option for kidney failure, particularly for the elderly and those with co-morbidities. Dietitians can play an important role in the provision of CKM by enhancing patients' quality of life through the management of nutrition impact symptoms (symptoms that result in decreased eating, including anorexia, nausea, dry mouth, and taste changes), as well as symptoms that result from malnutrition, including fatigue, weakness, activity intolerance, slow wound healing, and low mood. There are many gaps in the literature regarding optimal nutritional recommendations for patients on CKM. More research is needed on symptom management and interventions to delay or slow the progression of malnutrition and frailty. This article provides an overview of important nutritional considerations, a synthesis of the current literature, and recommendations for application of evidence into the practice of CKM.

[Soy protein as part of a low-protein diet is a new direction in cardio- and nephroprotection in patients with 3B-4 stages of chronic kidney disease: prospective, randomized, controlled clinical study]

BACKGROUND

It has been established that the use of a low-protein diet (LPD) in combination with ketoanalogues (KA) of essential amino acids can contribute to cardio- and nephroprotection in chronic kidney disease (CKD). Moreover, it has been shown that replacing part of the animal protein with soy protein (SP) in the diet contributed to more pronounced nephro- and cardioprotection in CKD, however, the data, available in the literature, are mainly represented by experimental studies.

AIM

To compare the effects of 2 types of diets on the main parameters of nephro- and cardioprotection in patients with CKD.

MATERIALS AND METHODS

We have conducted a prospective, randomized, controlled clinical study which included 85 patients with 3B4 stages of CKD, compliant to LPD (0.6 g of protein/kg body weight) + KA (1 tablet/5 kg body weight). 43 patients (Group 1) received LPD with replacing animal protein with soy (60% soy protein + 40% another vegetable proteins) + KA, and 42 patients (control group, Group 2) received LPD (60% animal protein + 40% vegetable protein) + KA, within 12 months.

RESULTS

The dietary substitution of animal protein with SP to a greater extent delayed the decrease in glomerular filtration rate (-5.9% vs -13.3%; p=0.048), the increase in left ventricular hypertrophy (+4.7% vs +12.3%; p=0.042), as well as the increase in central systolic blood pressure (+2.6% vs +13.0%; p=0.021), augmentation index (+7.6% vs +23.3%; p=0.010), slowed down the decrease in lean body mass in men (+0.9% vs -11.2%; p=0.017) and women (-1.8% vs -10.3%; p=0.024), increase in phosphorus (-10.3% vs +13.0%; p=0.029), cholesterol (-10.7% vs -3.4%; p=0.047) and urea (+6.3% vs +19.6%; p=0.035) serum levels.

CONCLUSION

The use of LPD with substitution of animal protein with soy protein + KA provides a more pronounced effect on nephro- and cardioprotection as well as maintenance of nutritional status, than conventional LPD + KA in patients with 3B4 stages of CKD.

Renal health benefits of sustainable diets in Japan: a review

Global warming may reduce food production and force people to adopt dietary habits of inadequate quantity or quality. Such dietary habits could trigger chronic kidney disease through inappropriate nutrition or lifestyle diseases. Livestock farming and other types of food production are responsible for many greenhouse gases. These problems are being emphasized as a diet-environment-health trilemma to be addressed on a global scale, with various methods being proposed toward its resolution. Diets like plant-based and low-protein diets not only potentially prevent the progression of chronic kidney disease, but are also rational from an environmental preservation perspective. Evidence from Japan on resolutions for this trilemma is sparse, but one concrete proposal is the use of traditional Japanese diets like washoku, the Okinawa diet, and the traditional Buddhist diet. However, traditional Japanese diets also have several problems, such as excessive salt content and caloric deficiencies, and need to be modified and incorporated into the current lifestyle. The progression of chronic kidney disease needs to be prevented with appropriate dietary treatment and environmental friendly manner.

Predialysis Urea Nitrogen Is a Nutritional Marker of Hemodialysis Patients

End-stage renal disease (ESRD) patients on hemodialysis have poor nutritional status and associated problems such as inflammation and sarcopenia. Blood urea nitrogen (BUN) is an important measure of uremic toxins, and urea reduction is a marker of hemodialysis efficacy. However, a low protein diet for lower BUN could aggravate malnutrition in patients, and optimal pre-dialysis BUN is not defined. We investigated the association of pre-dialysis BUN with patients' comorbidities and the relationship between pre-dialysis BUN and serum albumin as a nutrient marker. Among the 67 patients, the average pre- and post-dialysis BUN were 59.2 and 15.0 mg/dL, respectively, serum creatinine was 10.1 mg/dL, and the average serum albumin was 4.0 g/dL. Patients' age was negatively correlated with serum creatinine (r=-0.277, p<0.05) and albumin (r=-0.453, p<0.001). Predialysis BUN showed a significant positive correlation with serum albumin (r=0.287, p<0.05) and creatinine (r=0.454, p<0.001). However, the predialysis BUN was not significantly related to diabetes, coronary artery disease, congestive heart failure, or cerebrovascular disease. Hemodialysis patients with high pre-dialysis BUN and high serum creatinine could be regarded as having good nutritional status. The significance of this study lies in the potential utility of pre-dialysis blood urea nitrogen as an indicator of the nutritional status of patients. Liberal protein intake might be recommended to adequately dialyzed patients.

The association between low protein diet and body composition, muscle function, inflammation, and amino acid-based metabolic profile in chronic kidney disease stage 3-5 patients

BACKGROUND

Chronic kidney disease (CKD) is a global burden in the world. Low protein diet (LPD) recommendation is suggested in CKD patients to avoid or defer dialysis initiation and slow down CKD progression. However, nutritional imbalance and protein energy wasting represent key worries. The amino acid-based metabolic profile may provide a sensitive biomarker to evaluate CKD patients' nutrition status with LPD recommendations.

METHODS

We conducted a cross-sectional study in CKD stage 3-5 patients who had received LPD recommendation to evaluate the association between LPD and traditional markers (including plasma levels of albumin, pre-albumin, transferrin, total iron-binding capacity), inflammation markers (including peripheral leukocyte count and plasma levels of high-sensitivity C-reactive protein), body composition, muscle strength, and physical function, and novel nutrition markers (including amino acid-based metabolic profile) in CKD stage 3-5 patients.

RESULTS

In our study CKD stage 3-5 patients with the total number of 73, the mean age was around 71 ± 10 years old. The mean daily protein intake (DPI) was around 0.9 ± 0.3 g/kg/day and 25 (34%) patients met the recommended goal of DPI <0.8 g/kg/day. The mean daily calorie intake (DCI) was around 23 ± 6 kcal/kg/day, with only 11 (15%) patients met the recommend DCI with 30-35 kcal/kg/day. Compared to CKD patients with non-LPD, patients with LPD had significantly lower hemoglobin and albumin levels, shorter 6-min walking distance (6MWD), and lower leucine levels. Multivariable analysis found that lower hemoglobin and leucine levels, and shorter 6MWD were negatively and independently associated with LPD (all p < 0.05). Then ROC curve analysis found that the optimal cut-off value of leucine plasma levels was 95.5 μM with 60% sensitivity and 71% specificity to predict those CKD patients with LPD with the area under the curve of 0.646 (95% CI: 0.512-0.780).

CONCLUSION

LPD attainment was noted in 34% patients and most of CKD stage 3-5 patients (around 85%) had inadequate daily calorie intake although receiving standard dietary counseling routinely. A low protein diet and inadequate daily calorie intake in CKD patients were associated with shorter 6MWD, and lower hemoglobin and leucine levels. Plasma leucine levels lower than 95.5 μM may be a herald for muscle wasting and malnutrition in these CKD stage 3-5 patients with inadequate calorie intake.

Supplemented Low-Protein Diet May Delay the Need for Preemptive Kidney Transplantation: A Nationwide Population-Based Cohort Study

BACKGROUND

Although several studies suggest the benefit of a low-protein diet supplemented with amino acids and keto acids (sLPD) in delaying the initiation of hemodialysis, evidence on whether these nutritional approaches could delay the timing of preemptive transplantation is lacking.

METHODS

Retrospective nationwide cohort study, from Taiwan's National Health Insurance Research Database. Patients having undergone a first preemptive kidney transplantation between 2001 and 2017 were identified and divided into two groups according to the presence of sLPD treatment or not. The primary outcome was the time between the diagnosis of advanced CKD and transplantation. Secondary outcomes were post-transplantation adverse events.

RESULTS

A total of 245 patients who received their first preemptive kidney transplantation were identified from the nationwide database; 63 of them had been on an sLPD prior to transplantation (sLPD group). The duration between the day of advanced CKD diagnosis and the day of transplantation was significantly longer in the sLPD group compared with the non-sLPD group (median duration: 345 vs. 220 days, p = 0.001). The risk of post-transplantation adverse events did not differ between the two groups.

CONCLUSIONS

Within the limits of its observational, retrospective design, this is the first study to suggest that nutritional management with sLPDs can safely delay the timing of preemptive kidney transplantation.

Quality of Life in CKD Patients on Low-Protein Diets in a Multiple-Choice Diet System. Comparison between a French and an Italian Experience

Prescribing a low-protein diet (LPD) is part of the standard management of patients in advanced stages of chronic kidney disease (CKD). However, studies on the quality of life (QoL) of patients on LPDs are lacking, and the impact these diets have on their QoL is often given as a reason for not prescribing one. We, therefore, decided to assess the QoL in a cohort of CKD stage 3–5 patients followed up by a multiple-choice diet approach in an outpatient nephrology clinic in France. To do so, we used the short version of the World Health Organization’s quality of life questionnaire and compared the results with a historical cohort of Italian patients. We enrolled 153 patients, managed with tailored protein restriction in Le Mans, and compared them with 128 patients on similar diets who had been followed in Turin (Italy). We found there were no significant differences in terms of age (median 73 vs. 74 years, respectively), gender, CKD stage, and comorbidities (Charlson’s Comorbidity Index 7 vs. 6). French patients displayed a greater body mass index (29.0 vs. 25.4, p < 0.001) and prevalence of obesity (41.2 vs. 15.0%, p < 0.001). Baseline protein intake was over the target in France (1.2 g/kg of real body weight/day). In both cohorts, the burden of comorbidities was associated with poorer physical health perception while kidney function was inversely correlated to satisfaction with social life, independently of the type of diet. Our study suggests that the type of LPD they follow does not influence QoL in CKD patients and that a personalized approach towards protein restriction is feasible, even in elderly patients.

Ketoanalogs' Effects on Intestinal Microbiota Modulation and Uremic Toxins Serum Levels in Chronic Kidney Disease (Medika2 Study)

Nutritional therapy (NT) is a therapeutic option in the conservative treatment of chronic kidney disease (CKD) patients to delay the start of dialysis. The aim of this study was to evaluate the specific effect of ketoanalogs (KA)-supplemented diets for gut microbiota modulation. In a previous study we observed that the Mediterranean diet (MD) and a KA-supplemented very-low-protein diet (VLPD) modulated beneficially gut microbiota, reducing indoxyl- and p-cresyl-sulfate (IS, PCS) serum levels, and ameliorating the intestinal permeability in CKD patients. In the current study, we added a third diet regimen consisting of KA-supplemented MD. Forty-three patients with CKD grades 3B–4 continuing the crossover clinical trial were assigned to six months of KA-supplemented MD (MD + KA). Compared to MD, KA-supplementation in MD + KA determined (i) a decrease of Clostridiaceae, Methanobacteriaceae, Prevotellaceae, and Lactobacillaceae while Bacteroidaceae and Lachnospiraceae increased; (ii) a reduction of total and free IS and PCS compared to a free diet (FD)—more than the MD, but not as effectively as the VLPD. These results further clarify the driving role of urea levels in regulating gut integrity status and demonstrating that the reduction of azotemia produced by KA-supplemented VLPD was more effective than KA-supplemented MD in gut microbiota modulation mainly due to the effect of the drastic reduction of protein intake rather than the effect of KA.

Nutritional status improvement in elderly CKD patients: a systematic review

PURPOSE

Almost all CKD patients have a poor nutritional status, while elderly CKD patients are specifically frail and malnourished. Our aim is to conduct a systematic review of the up to date primary studies that look at methods of improving nutritional status in CKD patients in the elderly demographic.

METHODS

A focussed and sensitive search strategy was applied to the PUBMED database to identify relevant English language articles. Once articles were identified a detailed quality and bias assessment was performed. Two independent researchers (MZ and SM) then subsequently carried out detailed data extraction and analysis and this was subsequently verified by a third researcher (IN).

RESULTS

A total of 19 studies were included in our systematic review which included 7 non-randomised control trials and 15 randomised controlled trials. The outcomes that we considered to be most relevant for our subject title were: mortality data, SGA, albumin, total protein, isoleucine, leucine, prealbumin, transferrin, leptin, valine, TAG, HDL, LDL and total amino acids. Detailed bias analysis of the different studies was also conducted.

CONCLUSION

This is the first systematic review of the literature, so far, on the subject, involving elderly CKD patients. The quality of trials is low, very heterogenic in patients, methods and outcomes. However, we found a positive effect of dietary interventions on the nutritional status of most patients studied, highlighted by improvement in serum albumin and SGA, the most measured outcomes.

Low protein diets for non-diabetic adults with chronic kidney disease

BACKGROUND

Chronic kidney disease (CKD) is defined as reduced function of the kidneys present for 3 months or longer with adverse implications for health and survival. For several decades low protein diets have been proposed for participants with CKD with the aim of slowing the progression to end-stage kidney disease (ESKD) and delaying the onset of renal replacement therapy. However the relative benefits and harms of dietary protein restriction for preventing progression of CKD have not been resolved. This is an update of a systematic review first published in 2000 and updated in 2006, 2009 and 2018.

OBJECTIVES

To determine the efficacy of low protein diets in preventing the natural progression of CKD towards ESKD and in delaying the need for commencing dialysis treatment in non-diabetic adults.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 7 September 2020 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) or quasi RCTs in which adults with non-diabetic CKD (stages 3 to 5) not on dialysis were randomised to receive a very low protein intake (0.3 to 0.4 g/kg/day) compared with a low protein intake (0.5 to 0.6 g/kg/day) or a low protein intake compared with a normal protein intake (≥ 0.8 g/kg/day) for 12 months or more.

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies and extracted data. For dichotomous outcomes (death, all causes), requirement for dialysis, adverse effects) the risk ratios (RR) with 95% confidence intervals (CI) were calculated and summary statistics estimated using the random effects model. Where continuous scales of measurement were used (glomerular filtration rate (GFR), weight), these data were analysed as the mean difference (MD) or standardised mean difference (SMD) if different scales had been used. The certainty of the evidence was assessed using GRADE.

MAIN RESULTS

We identified 17 studies with 2996 analysed participants (range 19 to 840). Four larger multicentre studies were subdivided according to interventions so that the review included 21 separate data sets. Mean duration of participant follow-up ranged from 12 to 50 months. Random sequence generation and allocation concealment were considered at low risk of bias in eleven and nine studies respectively. All studies were considered at high risk for performance bias as they were open-label studies. We assessed detection bias for outcome assessment for GFR and ESKD separately. As GFR measurement was a laboratory outcome all studies were assessed at low risk of detection bias. For ESKD, nine studies were at low risk of detection bias as the need to commence dialysis was determined by personnel independent of the study investigators. Five studies were assessed at high risk of attrition bias with eleven studies at low risk. Ten studies were at high risk for reporting bias as they did not include data which could be included in a meta-analysis. Eight studies reported funding from government bodies while the remainder did not report on funding. Ten studies compared a low protein diet with a normal protein diet in participants with CKD categories 3a and b (9 studies) or 4 (one study). There was probably little or no difference in the numbers of participants who died (5 studies 1680 participants: RR 0.77, 95% CI 0.51 to 1.18; 13 fewer deaths per 1000; moderate certainty evidence). A low protein diet may make little or no difference in the number of participants who reached ESKD compared with a normal protein diet (6 studies, 1814 participants: RR 1.05, 95% CI 0.73 to 1.53; 7 more per 1000 reached ESKD; low certainty evidence). It remains uncertain whether a low protein diet compared with a normal protein intake impacts on the outcome of final or change in GFR (8 studies, 1680 participants: SMD -0.18, 95% CI -0.75 to 0.38; very low certainty evidence). Eight studies compared a very low protein diet with a low protein diet and two studies compared a very low protein diet with a normal protein diet. A very low protein intake compared with a low protein intake probably made little or no difference to death (6 studies, 681 participants: RR 1.26, 95% CI 0.62 to 2.54; 10 more deaths per 1000; moderate certainty evidence). However it probably reduces the number who reach ESKD (10 studies, 1010 participants: RR 0.65, 95% CI 0.49 to 0.85; 165 per 1000 fewer reached ESKD; moderate certainty evidence). It remains uncertain whether a very low protein diet compared with a low or normal protein intake influences the final or change in GFR (6 studies, 456 participants: SMD 0.12, 95% CI -0.27 to 0.52; very low certainty evidence). Final body weight was reported in only three studies. It is uncertain whether the intervention alters final body weight (3 studies, 89 participants: MD -0.40 kg, 95% CI -6.33 to 5.52; very low certainty evidence).Twelve studies reported no evidence of protein energy wasting (malnutrition) in their study participants while three studies reported small numbers of participants in each group with protein energy wasting. Most studies reported that adherence to diet was satisfactory. Quality of life was not formally assessed in any studies.

AUTHORS' CONCLUSIONS

This review found that very low protein diets probably reduce the number of people with CKD 4 or 5, who progress to ESKD. In contrast low protein diets may make little difference to the number of people who progress to ESKD. Low or very low protein diets probably do not influence death. However there are limited data on adverse effects such as weight differences and protein energy wasting. There are no data on whether quality of life is impacted by difficulties in adhering to protein restriction. Studies evaluating the adverse effects and the impact on quality of life of dietary protein restriction are required before these dietary approaches can be recommended for widespread use.

Green nephrology and eco-dialysis: a position statement by the Italian Society of Nephrology

High-technology medicine saves lives and produces waste; this is the case of dialysis. The increasing amounts of waste products can be biologically dangerous in different ways: some represent a direct infectious or toxic danger for other living creatures (potentially contaminated or hazardous waste), while others are harmful for the planet (plastic and non-recycled waste). With the aim of increasing awareness, proposing joint actions and coordinating industrial and social interactions, the Italian Society of Nephrology is presenting this position statement on ways in which the environmental impact of caring for patients with kidney diseases can be reduced. Due to the particular relevance in waste management of dialysis, which produces up to 2 kg of potentially contaminated waste per session and about the same weight of potentially recyclable materials, together with technological waste (dialysis machines), and involves high water and electricity consumption, the position statement mainly focuses on dialysis management, identifying ten first affordable actions: (1) reducing the burden of dialysis (whenever possible adopting an intent to delay strategy, with wide use of incremental schedules); (2) limiting drugs and favouring "natural" medicine focussing on lifestyle and diet; (3) encouraging the reuse of "household" hospital material; (4) recycling paper and glass; (5) recycling non-contaminated plastic; (6) reducing water consumption; (7) reducing energy consumption; (8) introducing environmental-impact criteria in checklists for evaluating dialysis machines and supplies; (9) encouraging well-planned triage of contaminated and non-contaminated materials; (10) demanding planet-friendly approaches in the building of new facilities.

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.

Intestinal microbiota alterations in chronic kidney disease and the influence of dietary components

In chronic kidney disease, as in many other diseases, dysbiosis of intestinal microbiota has been reported as a disturbance or imbalance of the normal microbiome content that could disrupt the symbiotic relationship between the host and associated microbes, a disruption that can result in diseases. The disruption of gut barrier function allows the translocation of endotoxins and bacterial metabolites to the organism, thus contributing to uremic toxicity, inflammation and progression of chronic kidney disease. Increased intake of some nutrients and different nutritional strategies have been proposed to modulate gut microbiota, thus offering the opportunity for therapeutic interventions modifying the diet, decreasing uremic toxins production, increasing toxin excretion and finally modifying the normal microbiome content. The use of probiotics, prebiotics and low protein diets, among other approaches, could also improve this imbalance and/or decrease permeability of the intestinal barrier. In this review, the link between nutrients, microbiota and uremic toxins with chronic kidney disease progression has been studied thoroughly. Furthermore, this review outlines potential mechanisms of action and efficacy of probiotics, prebiotics and low protein diets as a new chronic kidney disease management tool.

Green nephrology

Clear evidence indicates that the health of the natural world is declining globally at rates that are unprecedented in human history. This decline represents a major threat to the health and wellbeing of human populations worldwide. Environmental change, particularly climate change, is already having and will increasingly have an impact on the incidence and distribution of kidney diseases. Increases in extreme weather events owing to climate change are likely to have a destabilizing effect on the provision of care to patients with kidney disease. Ironically, health care is part of the problem, contributing substantially to resource depletion and greenhouse gas emissions. Among medical therapies, the environmental impact of dialysis seems to be particularly high, suggesting that the nephrology community has an important role to play in exploring environmentally responsible health-care practices. There is a need for increased monitoring of resource usage and waste generation by kidney care facilities. Opportunities to reduce the environmental impact of haemodialysis include capturing and reusing reverse osmosis reject water, utilizing renewable energy, improving waste management and potentially reducing dialysate flow rates. In peritoneal dialysis, consideration should be given to improving packaging materials and point-of-care dialysate generation.

Nutritional Therapy Modulates Intestinal Microbiota and Reduces Serum Levels of Total and Free Indoxyl Sulfate and P-Cresyl Sulfate in Chronic Kidney Disease (Medika Study)

In chronic kidney disease (CKD), the gut-microbiota metabolites indoxyl sulfate (IS) and p-cresyl sulfate (PCS) progressively accumulate due to their high albumin-binding capacity, leading to clinical complications. In a prospective crossover controlled trial, 60 patients with CKD grades 3B–4 (GFR = 21.6 ± 13.2 mL/min) were randomly assigned to two dietary regimens: (i) 3 months of free diet (FD) (FD is the diet usually used by the patient before being enrolled in the Medika study), 6 months of very low protein diet (VLPD), 3 months of FD and 6 months of Mediterranean diet (MD); (ii) 3 months of FD, 6 months of MD, 3 months of FD, and 6 months of VLPD. VLPD reduced inflammatory Proteobacteria and increased Actinobacteria phyla. MD and VLPD increased some butyrate-forming species of Lachnospiraceae, Ruminococcaceae, Prevotellaceae, Bifidobacteriaceae, and decrease the pathobionts Enterobacteriaceae. The increased level of potential anti-inflammatory Blautia and Faecalibacterium, as well as butyrate-forming Coprococcus and Roseburia species in VLPD was positively associated with dietary intakes and it was negatively correlated with IS and PCS. Compared to FD and MD, VLPD showed a lower amount of some Lactobacillus, Akkermansia, Streptococcus, and Escherichia species. MD and VLPD reduced both the total and free serum IS (MD −36%, −40% and VLPD −69%, −73%, respectively) and PCS (MD −38%, −44% and VLPD −58%, −71%, respectively) compared to FD. VLPD reduced serum D-lactate compared to MD and FD. MD and, to a greater extent, VLPD are effective in the beneficial modulation of gut microbiota, reducing IS and PCS serum levels, and restoring intestinal permeability in CKD patients.

Low protein diet with essential amino acids ketoanalogues combination can affect serum FGF-23 and Klotho levels in chronic kidney disease 3b-4 stages patients: randomized pilot study

Protein restriction diet (PRD) with ketoanalagues of essential amino acids (KA) combination can improve of chronic kidney disease (CKD) course while, the precise mechanisms of PRD + KAA action in CKD are not known yet. We have conducted a prospective, randomized, controlled study of PRD and KAA patient’s group in compare with PRD without KAA group in regarding to serum Klotho and FGF-23 levels in patients with CKD. Materials and methods. The study included 79 CKD 3b-4 stages patients, non - diabetic etiology, used PRD (0.6 g/kg/day). The patients were randomized in two groups: 42 patients, received PRD + KAA (Group 1) and 37 patients continued the PRD without KAA (Group 2). Serum FGF-23 (Human FGF-23 ELISA kit with antibodies to native FGF-23 molecule, Merk Millipore MILLENZFGF-23-32K), Klotho (Human soluble Klotho with antiKlotho monoclonal antibodies, IBL-Takara 27998-96Well) levels, as well as instrumental examination: bioimpedance analysis [assess of muscle body mass (MBM), fat body mass (FBM), body mass index (BMI) and others]; sphygmography [assess of augmentation (stiffness) indices (AI), central (aortal) blood pressure (CBP) by «Sphygmacor» device]; as well as echocardiography [assess of cardiac (valvular) calcification score (CCS) and left ventricular myocardium mass index (LVMMI)], were studded in addition to conventional examination. Results and discussion. To the end of 14th month of the study the PRD group reached a body mass index (BMI) decrease (p=0.046), including MBM in men (p=0.027) and woman (p=0.044). In addition, higher FGF-23 (p=0.029), and lower Klotho (p=0.037) serum levels were revealed in the PRD group compared to the PRD+KAA group as well as the increase in AI (p=0.034), CCS (p=0.048), and LVMMI (p=0.023). Conclusion. Use of PRD + KAA provides adequate nutrition status and more efficient correction of FGF-23 and Klotho imbalance in CKD progression that may contribute to alleviation of both cardiovascular calcification and cardiac remodeling in CKD. Importantly, a prolonged PRD use without supplementation of KAA may lead to malnutrition signs.

Vegetable-Based Diets for Chronic Kidney Disease? It Is Time to Reconsider

Traditional dietary recommendations to renal patients limited the intake of fruits and vegetables because of their high potassium content. However, this paradigm is rapidly changing due to the multiple benefits derived from a fundamentally vegetarian diet such as, improvement in gut dysbiosis, reducing the number of pathobionts and protein-fermenting species leading to a decreased production of the most harmful uremic toxins, while the high fiber content of these diets enhances intestinal motility and short-chain fatty acid production. Metabolic acidosis in chronic kidney disease (CKD) is aggravated by the high consumption of meat and refined cereals, increasing the dietary acid load, while the intake of fruit and vegetables is able to neutralize the acidosis and its deleterious consequences. Phosphorus absorption and bioavailability is also lower in a vegetarian diet, reducing hyperphosphatemia, a known cause of cardiovascular mortality in CKD. The richness of multiple plants in magnesium and vitamin K avoids their deficiency, which is common in these patients. These beneficial effects, together with the reduction of inflammation and oxidative stress observed with these diets, may explain the reduction in renal patients' complications and mortality, and may slow CKD progression. Finally, although hyperkalemia is the main concern of these diets, the use of adequate cooking techniques can minimize the amount absorbed.

Phase resetting of circadian peripheral clocks using human and rodent diets in mouse models of type 2 diabetes and chronic kidney disease

The expression rhythms of clock genes, such as Per1, Per2, Bmal1, and Rev-erb α, in mouse peripheral clocks, are entrained by a scheduled feeding paradigm. In terms of food composition, a carbohydrate-containing diet is reported to cause strong entrainment through insulin secretion. However, it is unknown whether human diets entrain peripheral circadian clocks. In this study, we used freeze-dried diets for type 2 diabetes (DB) and chronic kidney disease (CKD), as well as low-carbohydrate diets. After 24 h of fasting, PER2::LUC knock-in mice were given access to food for 2 days during inactive periods, and bioluminescence rhythm was then measured using an in vivo imaging system. AIN-93M, the control mouse diet with a protein:fat:carbohydrate (PFC) ratio of 14.7:9.5:75.8, caused a significant phase advance (7.3 h) in the liver clock compared with that in 24 h fasted mice, whereas human diets caused significant but smaller phase advances (4.7-6.2 h). Compared with healthy and high fat/sucrose-induced DB mice, adenine-induced CKD mice showed attenuation of a phase-advance with a normal diet. There were no significant differences in phase-advance values between human diets (normal, DB, and CKD). In addition, a normal-carbohydrate diet (PFC ratio of 20.3:23.3:56.4) and a low-carbohydrate diet (PFC ratio of 36.4:42.9:20.7) caused similar phase advances in peripheral clocks. The present results strongly suggest that scheduled feeding with human diets can cause phase advances in the peripheral clocks of not only healthy, but also DB and CKD mice. This discovery provides support to the food-induced entrainment of peripheral clocks in human clinical trials.

Psychosocial Issues and Lifestyle Changes for the Renal Patient

This article provides an overview of the psychosocial issues faced by those with renal disease. The article discusses the physiologic connection between anxiety, depression, and pain-symptoms commonly seen in renal disease and other chronic illnesses. The application of integrative medicine or nonallopathic medicine and its role in the management of anxiety, depression, and pain are presented. Also presented is evidence surrounding several frequently used nonallopathic modalities appropriate for incorporation into a comprehensive management regimen for renal patients to reduce symptom burden. The article concludes with a discussion on the role of palliative care in treatment decisions for renal patients.

Low protein diets for non-diabetic adults with chronic kidney disease

BACKGROUND

Chronic kidney disease (CKD) is defined as reduced function of the kidneys present for 3 months or longer with adverse implications for health and survival. For several decades low protein diets have been proposed for participants with CKD with the aim of slowing the progression to end-stage kidney disease (ESKD) and delaying the onset of renal replacement therapy. However the relative benefits and harms of dietary protein restriction for preventing progression of CKD have not been resolved. This is an update of a systematic review first published in 2000 and updated in 2006 and 2009.

OBJECTIVES

To determine the efficacy of low protein diets in preventing the natural progression of CKD towards ESKD and in delaying the need for commencing dialysis treatment in non-diabetic adults.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 2 March 2018 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) or quasi RCTs in which adults with non-diabetic chronic kidney disease (stages 3 to 5) not on dialysis were randomised to receive a very low protein intake (0.3 to 0.4 g/kg/d) compared with a low protein intake (0.5 to 0.6 g/kg/d) or a low protein intake compared with a normal protein intake (≥ 0.8 g/kg/d) for 12 months or more.

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies and extracted data. For dichotomous outcomes (death, all causes), requirement for dialysis, adverse effects) the risk ratios (RR) with 95% confidence intervals (CI) were calculated and summary statistics estimated using the random effects model. Where continuous scales of measurement were used (glomerular filtration rate (GFR), weight), these data were analysed as the mean difference (MD) or standardised mean difference (SMD) if different scales had been used. The certainty of the evidence was assessed using GRADE.

MAIN RESULTS

We identified an additional six studies to include 17 studies with 2996 analysed participants (range 19 to 840). Four larger multicentre studies were subdivided according to interventions so that the review included 21 separate data sets. Mean duration of participant follow-up ranged from 12 to 50 months.Random sequence generation and allocation concealment were considered at low risk of bias in eleven and nine studies respectively. All studies were considered at high risk for performance bias as they were open-label studies. We assessed detection bias for outcome assessment for GFR and ESKD separately. As GFR measurement was a laboratory outcome all studies were assessed at low risk of detection bias. For ESKD, nine studies were at low risk of detection bias as the need to commence dialysis was determined by personnel independent of the study investigators. Five studies were assessed at high risk of attrition bias with eleven studies at low risk. Ten studies were at high risk for reporting bias as they did not include data which could be included in a meta-analysis. Eight studies reported funding from government bodies while the remainder did not report on funding.Ten studies compared a low protein diet with a normal protein diet in participants with CKD categories 3a and b (9 studies) or 4 (one study). There was probably little or no difference in the numbers of participants who died (5 studies 1680 participants: RR 0.77, 95% CI 0.51 to 1.18; 13 fewer deaths per 1000; moderate certainty evidence). A low protein diet may make little or no difference in the number of participants who reached ESKD compared with a normal protein diet (6 studies, 1814 participants: RR 1.05, 95% CI 0.73 to 1.53; 7 more per 1000 reached ESKD; low certainty evidence). It remains uncertain whether a low protein diet compared with a normal protein intake impacts on the outcome of final or change in GFR (8 studies, 1680 participants: SMD -0.18, 95% CI -0.75 to 0.38; very low certainty evidence).Eight studies compared a very low protein diet with a low protein diet and two studies compared a very low protein diet with a normal protein diet. A very low protein intake compared with a low protein intake probably made little or no difference to death (6 studies, 681 participants: RR 1.26, 95% CI 0.62 to 2.54; 10 more deaths per 1000; moderate certainty evidence). However it probably reduces the number who reach ESKD (10 studies, 1010 participants: RR 0.65, 95% CI 0.49 to 0.85; 165 per 1000 fewer reached ESKD; moderate certainty evidence). It remains uncertain whether a very low protein diet compared with a low or normal protein intake influences the final or change in GFR (6 studies, 456 participants: SMD 0.12, 95% CI -0.27 to 0.52; very low certainty evidence).Final body weight was reported in only three studies. It is uncertain whether the intervention alters final body weight (3 studies, 89 participants: MD -0.40 kg, 95% CI -6.33 to 5.52; very low certainty evidence).Twelve studies reported no evidence of protein energy wasting (malnutrition) in their study participants while three studies reported small numbers of participants in each group with protein energy wasting. Most studies reported that adherence to diet was satisfactory. Quality of life was not formally assessed in any studies.

AUTHORS' CONCLUSIONS

This review found that very low protein diets probably reduce the number of people with CKD 4 or 5, who progress to ESKD. In contrast low protein diets may make little difference to the number of people who progress to ESKD. Low or very low protein diets probably do not influence death. However there are limited data on adverse effects such as weight differences and protein energy wasting. There are no data on whether quality of life is impacted by difficulties in adhering to protein restriction. Studies evaluating the adverse effects and the impact on quality of life of dietary protein restriction are required before these dietary approaches can be recommended for widespread use.

Adequacy of Plant-Based Proteins in Chronic Kidney Disease

Concerns regarding protein and amino acid deficiencies with plant-based proteins have precluded their use in chronic kidney disease (CKD) patients. Many of these concerns were debunked years ago, but recommendations persist regarding the use of "high-biological value" (animal-based) proteins in CKD patients, which may contribute to worsening of other parameters such as blood pressure, metabolic acidosis, and hyperphosphatemia. Plant-based proteins are sufficient in meeting both quantity and quality requirements. Those eating primarily plant-based diets have been observed to consume approximately 1.0 g/kg/day of protein, or more. CKD patients have been seen to consume 0.7-0.9 g/kg/day of mostly plant-based protein without any negative effects. Furthermore, those substituting animal-based proteins for plant-based proteins have shown reductions in severity of hypertension, hyperphosphatemia, and metabolic acidosis. Plant-based proteins, when consumed in a varied diet, are not only nutritionally adequate but have pleiotropic effects which may favor their use in CKD patients.

Microbiota issue in CKD: how promising are gut-targeted approaches?

In chronic kidney disease (CKD), the progressive decline in the renal excretory function leads to accumulation of urea and toxins in the blood. The CKD-associated dysbiosis of gut microbiota further contributes to uremia by increasing intestinal toxins production. Gut microbiota is involved in a complex network of human organs, mediated by microbial metabolites: in CKD, gut-heart and gut-brain axes may have a role in increased cardiovascular risk and neuropsychiatric disorders. While the cardiovascular toxicity of some microbial molecules is well known, their presumptive neurotoxicity needs to be confirmed by specific studies. In this review, we describe gut-heart and gut-brain axes in CKD, with an overview of the experimental and human studies characterizing CKD-associated gut microbiota, and we discuss the benefits coming from new approaches aimed at gut manipulation. Microbiota metabolism is emerging as a modifiable non-traditional risk factor in nephrology. In order to take advantage of this issue, it is necessary to consider the microbiota manipulation as part of the nutritional management of CKD. Integrating the low-protein nutritional approach with prebiotic, probiotic and synbiotic supplementation is a promising tool to control disease progression and comorbidities, though an extensive validation in large-scale clinical trials is still required.

Effect of essential amino acid кetoanalogues and protein restriction diet on morphogenetic proteins (FGF-23 and Кlotho) in 3b-4 stages chronic кidney disease patients: a randomized pilot study

BACKGROUND

A low protein diet (LPD) with essential amino acid ketoanalogue supplementation (KA) may contribute in improving of chronic kidney disease (CKD), while the exact mechanisms of KA's effect are not established yet. We have conducted a prospective, randomized, controlled comparative study of LPD + KA and LPD alone in relation to serum Klotho, FGF-23 levels in CKD patients.

METHODS

79 non-diabetic CKD 3b-4 stage patients, compliant with LPD diet (0.6 g/kg of body weight/day), had been selected. The patients were randomized into two groups. The first group (42 patients) received LPD + КA. The second group (37 patients) continued the LРD alone. In addition to routine tests, serum Klotho, FGF-23 levels, as well as bioimpedance analysis, sphygmography (stiffness (augmentation) indices (AI), central (aortal) blood pressure) with a «SphygmaCor» device; echocardiography (valvular calcification score (VCS) and LVMMI), were performed.

RESULTS

There were body mass indices' decrease (p = 0.046), including muscle body mass in men (p = 0.027) and woman (p = 0.044) in the LPD group to the end of study (14th month). In addition, lower FGF-23 (p = 0.029), and higher sKlotho (p = 0.037) were detected in the LPD + KA group compared to the LPD one. The increase in AI (p = 0.034), VCS (p = 0.048), and LVMMI (p = 0.023) was detected more often in the LPD group at the end of study.

CONCLUSION

LPD + KA provides support for nutrition status and contributes to more efficient correction of FGF-23 and Klotho abnormalities that may result in cardiovascular calcification and cardiac remodeling decreasing in CKD. At the same time, a prolonged LPD alone may lead to malnutrition.

The strange case of Mr. H. Starting dialysis at 90 years of age: clinical choices impact on ethical decisions

Background

Starting dialysis at an advanced age is a clinical challenge and an ethical dilemma. The advantages of starting dialysis at “extreme” ages are questionable as high dialysis-related morbidity induces a reflection on the cost- benefit ratio of this demanding and expensive treatment in a person that has a short life expectancy. Where clinical advantages are doubtful, ethical analysis can help us reach decisions and find adapted solutions.

Case presentation

Mr. H is a ninety-year-old patient with end-stage kidney disease that is no longer manageable with conservative care, in spite of optimal nutritional management, good blood pressure control and strict clinical and metabolic evaluations; dialysis is the next step, but its morbidity is challenging. The case is analysed according to principlism (beneficence, non-maleficence, justice and respect for autonomy).

In the setting of care, dialysis is available without restriction; therefore the principle of justice only partially applied, in the absence of restraints on health-care expenditure. The final decision on whether or not to start dialysis rested with Mr. H (respect for autonomy). However, his choice depended on the balance between beneficence and non-maleficence. The advantages of dialysis in restoring metabolic equilibrium were clear, and the expected negative effects of dialysis were therefore decisive. Mr. H has a contraindication to peritoneal dialysis (severe arthritis impairing self-performance) and felt performing it with nursing help would be intrusive. Post dialysis fatigue, poor tolerance, hypotension and intrusiveness in daily life of haemodialysis patients are closely linked to the classic thrice-weekly, four-hour schedule. A personalized incremental dialysis approach, starting with one session per week, adapting the timing to the patient’s daily life, can limit side effects and “dialysis shock”.

Conclusions

An individualized approach to complex decisions such as dialysis start can alter the delicate benefit/side-effect balance, ultimately affecting the patient’s choice, and points to a narrative, tailor-made approach as an alternative to therapeutic nihilism, in very old and fragile patients.

Chronic kidney disease progression: a retrospective analysis of 3-year adherence to a low protein diet

The potential benefits and dangers of dietary protein restriction in chronic kidney disease (CKD) are still controversial. Thus, the aim of this study is to evaluate the effect of low protein diet (LPD) on the renal function in nondialysis CKD patients. A retrospective study was conducted from 321 nondialysis CKD patient's medical files (65.1 ± 12.7 yrs, 58.2% men). These patients received individualized dietary protein prescription (0.6-0.8 g protein/kg/day). Protein intake was evaluated by food diary and 24 h-food recall. Adherence to the LPD was considered when patients intake from 90 to 110% of the prescribed amount of protein. The patients were divided into 4 groups: (G1) adherent diabetes mellitus (DM) patients (n = 83); (G2) non-adherent DM patients (n = 106); (G3) adherent non-DM patients (n = 75); (G4) non-adherent non-DM patients (n = 57). Renal function was assessed by estimated glomerular filtration rate (eGFR). Both groups of patients (DM and non-DM) that adhered to the LPD showed significant improvement in eGFR (G1: 38.7 ± 13.2 mL/min to 51.1 ± 17.0 mL/min (p < 0.001); G3: 35.1 ± 16.8 mL/min to 46.8 ± 21.4 mL/min (p < 0.001)). In adherent patients, no differences in albumin and BMI were observed at the end of follow up. In non-adherent patients, eGFR significantly decreased in DM group (G2: 44.2 ± 18.5 mL/min to 38.2 ± 15.8 mL/min (p = 0.003)). According to multivariate analysis, annual changes in eGFR were not independent associated with age, gender, BMI, lipid profile, bicarbonate or smoking status. In summary, adherence to low protein diet could be able to improve serum creatinine and eGFR, well-known markers of renal function. However, prospective studies are needed to control confounders which affect renal function and CKD progression.

Dietary Phosphorus Intake and the Kidney

Although phosphorus is an essential nutrient required for multiple physiological functions, recent research raises concerns that high phosphorus intake could have detrimental effects on health. Phosphorus is abundant in the food supply of developed countries, occurring naturally in protein-rich foods and as an additive in processed foods. High phosphorus intake can cause vascular and renal calcification, renal tubular injury, and premature death in multiple animal models. Small studies in human suggest that high phosphorus intake may result in positive phosphorus balance and correlate with renal calcification and albuminuria. Although serum phosphorus is strongly associated with cardiovascular disease, progression of kidney disease, and death, limited data exist linking high phosphorus intake directly to adverse clinical outcomes. Further prospective studies are needed to determine whether phosphorus intake is a modifiable risk factor for kidney disease.

The systemic nature of CKD

The accurate definition and staging of chronic kidney disease (CKD) is one of the major achievements of modern nephrology. Intensive research is now being undertaken to unravel the risk factors and pathophysiologic underpinnings of this disease. In particular, the relationships between the kidney and other organs have been comprehensively investigated in experimental and clinical studies in the last two decades. Owing to technological and analytical limitations, these links have been studied with a reductionist approach focusing on two organs at a time, such as the heart and the kidney or the bone and the kidney. Here, we discuss studies that highlight the complex and systemic nature of CKD. Energy balance, innate immunity and neuroendocrine signalling are highly integrated biological phenomena. The diseased kidney disrupts such integration and generates a high-risk phenotype with a clinical profile encompassing inflammation, protein-energy wasting, altered function of the autonomic and central nervous systems and cardiopulmonary, vascular and bone diseases. A systems biology approach to CKD using omics techniques will hopefully enable in-depth study of the pathophysiology of this systemic disease, and has the potential to unravel critical pathways that can be targeted for CKD prevention and therapy.

Low-protein diet for the prevention of renal failure

The prevalence of chronic kidney disease (CKD) is estimated to be 8-16% worldwide, and it is increasing. CKD is a risk factor for heart attack and stroke, and it can progress to kidney failure requiring dialysis or transplantation. Recently, diabetic nephropathy has become the most common cause of CKD. In Japan, the cumulative probability of requiring hemodialysis by the age 80 years is 1/50 in males and 1/100 in females. The number of patients under hemodialysis in Japan exceeded 320,000 in 2014, among which 38,000 were newcomers and 27,000 died.The annual medical costs of hemodialysis are 1.25 trillion yen in Japan, representing 4% of the total national medical expenditures in 2014. A low-protein diet (less than 0.5 g/kg b.wt.) is a very effective intervention. Low-protein rice (1/10 to 1/25 of the normal protein contents) is helpful to control the consumption of proteins, decreasing at the same time the intake of potassium and phosphate.Protein restriction is indicated as soon as the eGFR becomes lower than 60 ml/min/1.73 m² body surface, in order, to slow disease progression. The newly developed low-protein Indica rice is expected to help many CKD patients in China and Southeast Asia.

Dietary protein intake and chronic kidney disease

PURPOSE OF REVIEW

High-protein intake may lead to increased intraglomerular pressure and glomerular hyperfiltration. This can cause damage to glomerular structure leading to or aggravating chronic kidney disease (CKD). Hence, a low-protein diet (LPD) of 0.6-0.8 g/kg/day is often recommended for the management of CKD. We reviewed the effect of protein intake on incidence and progression of CKD and the role of LPD in the CKD management.

RECENT FINDINGS

Actual dietary protein consumption in CKD patients remains substantially higher than the recommendations for LPD. Notwithstanding the inconclusive results of the 'Modification of Diet in Renal Disease' (MDRD) study, the largest randomized controlled trial to examine protein restriction in CKD, several prior and subsequent studies and meta-analyses appear to support the role of LPD on retarding progression of CKD and delaying initiation of maintenance dialysis therapy. LPD can also be used to control metabolic derangements in CKD. Supplemented LPD with essential amino acids or their ketoanalogs may be used for incremental transition to dialysis especially on nondialysis days. The LPD management in lieu of dialysis therapy can reduce costs, enhance psychological adaptation, and preserve residual renal function upon transition to dialysis. Adherence and adequate protein and energy intake should be ensured to avoid protein-energy wasting.

SUMMARY

A balanced and individualized dietary approach based on LPD should be elaborated with periodic dietitian counseling and surveillance to optimize management of CKD, to assure adequate protein and energy intake, and to avoid or correct protein-energy wasting.

Kidney Disease: Personalized Lifestyle Health Care Makes a Big Difference

We cannot solve the kidney disease problem through the building of more dialysis centers or by providing a greater number of kidney transplants. We must find a way to implement effective lifestyle management programs if we truly want to bend the curve and decrease the prevalence of kidney disease. The solution to the chronic kidney disease challenge lies in the skilled application of personalized lifestyle health care. Achieving this goal represents a tremendous opportunity for multidisciplinary collaboration and integration.

Retarding Chronic Kidney Disease (CKD) Progression: A Practical Nutritional Approach for Non-Dialysis CKD

This is a case report on a patient with non-dialysis chronic kidney disease (CKD) in whom several nutritional issues are briefly discussed from a practical point of view. The article is accompanied by an editorial published in this Journal in relation to the 2nd International Conference of the European Renal Nutrition working group at ERA-EDTA—“Retarding CKD progression: readily available through comprehensive nutritional management?”— and focuses on several practical topics associated with the nutritional approach for the conservative treatment of non-dialysis CKD. The article is divided into 3 sections—basic nutritional assessment, nutritional targets, and nutritional follow-up in non-dialysis CKD—linked to 3 consecutive steps of the clinical follow-up of the patient and the related nutritional concerns and intervention.

First visit: Baseline nutritional assessment and basic nutritional considerations in non-dialysis chronic kidney disease (CKD) • What nutritional assessment/monitoring for protein-energy wasting (PEW) should be employed? • Is a body mass index (BMI) of 21 kg/m2 adequate? • What phosphate target should be pursued? • What are the nutritional habits in patients with incident CKD? • What protein needs and amount of dietary protein should be pursued? • Does the quality of protein matter? • What amount of dietary salt should be employed? How should this be obtained? • How should normal serum phosphate be achieved? • What diet should be recommended? Is a vegetarian diet an option?

Second visit: Major nutritional targets in non-dialysis CKD • Consequences of unintentional weight loss • What is the role of the renal dietitian in helping the patient adhere to a renal diet?

Intermediate visits: Nutritional follow-up in non-dialysis CKD • What treatment for calcium/parathyroid hormone (PTH) will affect CKD progression? Final visits: • Would a dietary recall/intensive dietary education improve adherence with the diet? • Would a very-low-protein diet (VLPD)/ketodiet be indicated for this patient?