Plant-Dominant Low-Protein Diet for Conservative Management of Chronic Kidney Disease

Sustainability and role of plant-based diets in chronic kidney disease prevention and treatment

Chronic kidney disease (CKD) affects 10% of the world's population (namely, 800 million of people) and an increase in CKD prevalence has been observed over the years. This phenomenon in developed countries is related to the spread of chronic degenerative non-communicable diseases (CDNCDs), such as diabetes mellitus, arterial hypertension, obesity, etc., while in low-income to middle-income countries, the CKD prevalence is attributable not only to CDNCDs, but also to infection conditions (like HIV, hepatitis, etc.). Another important difference lies in the age of onset of CKD, which is about 20 years lower in developing countries compared to developed ones. Therefore, CKD is becoming a public health problem, requiring preventive and treatment strategies to counteract its spread and to slow its progression. Moreover, the healthcare costs for the CKD management increase as the disease progresses. In this regard, the approach to prevent and reduce the CKD progression involves pharmacological and nutritional treatments (like Mediterranean Diet, MedRen diet, Flexitarian Diet, Vegetarian Diet and Plant-dominant Low Protein Diet) in order to improve the patients' quality of life and, at the same time, promote the environmental sustainability. Recent studies have highlighted the benefits of these diets not only for individuals, but also for environment. In particular, plant-based diets have increasingly gained an important role in the prevention and management of chronic diseases, including CKD. In fact, recent scientific studies have highlighted how a greater adherence to predominantly plant-based diets, is associated with a lower risk in developing CKD and also in slowing its progression. With regard to environmental sustainability, it is known how our food choices influence the climate crisis, since the food sector contributes for the 25% to the greenhouse gas emissions. Therefore, to reduce the consumption of animal proteins and to replace them with plant-based proteins are key strategies for sustainability and health, also supported by the European policies. In this context, food industries are starting to increase the offer of plant-based products that have similar characteristics, both sensorial and nutritional, to those of animal origin. This innovation, in fact, presents difficulties due to the perception of taste and the organoleptic appearance of these products. An additional challenge concerns the resistance of the traditional food industry and the lack of awareness of the consumer. The paradigm shift is dictated by the obtained benefits for health and for environment. Life cycle assessment studies have compared the land footprint, carbon footprint and blue water footprint of plant-based products with those of animal origin and pointed out the lower environmental impact of the former. In conclusion, the adoption of sustainable food models will slow down the spread of CDNCDs, such as CKD, positively impacting both on human health and on planet, significantly reducing the costs and resources of the National Health Systems, since they absorb up to 70%-80% of the healthcare costs.

Global, regional, and National Burden of chronic kidney disease attributable to dietary risks from 1990 to 2021

Background

Dietary risks are increasingly reported as a cause of chronic kidney disease (CKD). However, the trends in the burden of CKD attributable to dietary risks have yet to be fully elucidated.

Methods

This study extracted two major indicators related to CKD caused by dietary risks from the Global Burden of Disease (GBD) database for the years 1990 to 2021, including deaths and disability-adjusted life years (DALYs). It used estimated annual percentage change (EAPC) and percentage change to assess the trends in the burden of CKD caused by dietary risks. The relationship between Socio-demographic Index (SDI) and disease burden was also further analyzed. Additionally, we utilized the contemporary age-period-cohort model from NORDPRED to project future burden of CKD attributable to dietary risks.

Results

In 2021, globally, the number of deaths due to CKD caused by dietary risks was 317,010, and the number of DALYs was 7,971,281, approximately 2-3 times that of 1990, and it was expected to continue to rise before 2040. The global death rates and DALY rates of CKD related to dietary risks had increased, with EAPCs of 0.63 (95% CI: 0.57 to 0.69) and 0.39 (95% CI: 0.35 to 0.42), respectively. From a gender perspective, men were more likely to suffer from CKD due to dietary risks. From an age pattern perspective, in 2021, the number of deaths due to CKD caused by dietary risks peaked among men aged 70-74 and women aged 85-89. Additionally, the highest number of DALYs due to CKD caused by dietary risks was observed among men and women aged 65-69. In terms of socioeconomic factors, from 1990 to 2021, as the SDI increased, the age-standardized death rates and DALY rates due to CKD caused by dietary risks generally decreased. Among the seven dietary habits related to dietary risks, low vegetable intake, low fruit intake, and high sodium intake had the greatest impact.

Conclusion

In summary, over the past 32 years, the burden of CKD attributable to dietary risks has rapidly increased globally, and it is expected to continue rising until 2040. Therefore, interdisciplinary actions involving education, policy, and healthcare should be taken to mitigate this growing trend.

Nutritional counseling's impact on muscle mass and quality of life in stage 4 chronic kidney disease malnourished patients

BackgroundChronic Kidney Disease (CKD) is a significant public health issue, affecting 37 million people in the United States. CKD often leads to malnutrition, particularly in advanced stages, contributing to muscle wasting, reduced quality of life, and increased healthcare costs.ObjectiveThis retrospective study aimed to investigate the impact of early nutritional intervention and counseling on muscle mass and quality of life in malnourished stage 4 chronic kidney disease (CKD) patients.MethodsClinical data from stage 4 CKD patients with concomitant malnutrition admitted to a single center from January 2023 to December 2023 were retrospectively analyzed. Patients were divided into a standard intervention group and an early nutritional intervention and counseling group. Baseline characteristics, muscle mass parameters, quality of life assessments, nutritional parameters, and adverse events were compared between the two groups.ResultsThe baseline characteristics of the study participants were well-balanced between the two groups. The early nutrition intervention group demonstrated significant improvements in muscle mass parameters, including grip strength, skeletal muscle mass, muscle strength, calf circumference, and handgrip measurement, compared to the standard intervention group. Additionally, the early nutrition intervention group showed significant enhancements in several aspects of quality of life, including physical functioning, mental health, energy/fatigue, and general health scores. Improvements in nutritional parameters, such as protein intake, caloric intake, vitamin D levels, iron levels, and zinc levels, were also observed in the early nutrition intervention group. Notably, no significant differences in adverse events were found between the two groups.ConclusionThe study highlights the significant benefits of early nutritional intervention and counseling for malnourished stage 4 CKD patients. Early nutritional support positively impacts muscle mass, quality of life, and nutritional parameters. These findings emphasize the importance of nutrition in CKD management and the need for comprehensive nutritional support as a key component of care. This research paves the way for further studies and clinical initiatives to enhance nutritional care and improve the standard of care for CKD patients.

Association Between Potential Renal Acid Load and 10-Year Mortality in Patients on Hemodialysis

OBJECTIVES

Higher dietary acid load (DAL) has been linked to elevated incidence and progression of chronic kidney disease. However, the association between DAL and mortality in patients on maintenance hemodialysis (MHD) has not been evaluated.

METHODS

We retrospectively analyzed baseline laboratory data, self-administered diet history questionnaire results, and 10-year mortality rates in 44 patients (26 men, 67.9 ± 10.4 years) on MHD who participated in a randomized, double-blind, crossover pilot trial of rice endosperm protein supplementation, which was conducted in 2013. DAL was estimated from nutrition intake using potential renal acid load (PRAL), and patients were divided into tertiles using this score.

RESULTS

During the 10-year observation period, 19 patients (43%) died. A higher PRAL score was significantly associated with higher all-cause mortality. The multivariable-adjusted hazard ratio for all-cause mortality in the highest tertile of PRAL versus the lowest tertile was 3.88 (95% confidence interval [CI], 1.10-13.61). Multiple logistic regression analysis showed a significant association between higher PRAL and lower intake of green and yellow vegetables (odds ratio, 5.40; 95% CI, 1.37-21.26) and fruits (odds ratio, 4.76; 95% CI, 1.30-16.76).

CONCLUSIONS

Higher PRAL is positively associated with all-cause mortality, and these associations might be affected by a lower intake of fruits and vegetables in Japanese patients on MHD.

Baseline renal function modified the association between total, plant or animal protein intake and the risk of developing renal composite outcome in people with type 2 diabetes: a prospective cohort study [diabetes distress and care registry at Tenri (DDCRT25)]

AIMS

This study aimed to identify the longitudinal associations between protein intake, and composite renal outcomes in people with type 2 diabetes.

METHODS

To examine the association between baseline total, animal, and plant protein intake and the risk of developing a composite renal outcome in 3,109 Japanese people with type 2 diabetes who participated in a cohort study at a tertiary care hospital, we used a Cox proportional hazards model.

RESULTS

During a median follow-up of 6.0 years, we observed 185 renal outcomes. Compared with the 1st quintile, the multivariable-adjusted HRs for outcome were 1.13 (p = 0.440), 1.04 (pp= 0.874), 1.40 (p = 0.215), and 2.16 (p = 0.001), respectively for the 2nd to 5th quintile of total protein intake, and 0.93 (p = 0.681), 1.1 (p= 0.596), 1.1 (p = 0.607), and 2.02 (p < 0.001), respectively for the 2nd to 5th quintile of animal protein intake. However, a significant association of total plant intake was not observed. In the analysis evaluating the joint association between protein intake and composite renal outcome with baseline estimated glomerular filtration ratio (eGFR), total protein and animal protein intake were substantially associated with a higher risk of composite renal outcome when the baseline eGFR was below approximately 60 mL/min/1.732.

CONCLUSIONS

Baseline total protein intake is associated with a higher risk of developing a composite renal outcome during follow-up in people with type 2 diabetes and low baseline eGFR, and this association may be elucidated by a higher animal protein intake. Plant protein was not associated with renal outcome.

Dietary Fiber Intake and Clinical Outcomes in Chronic Kidney Disease: A Report From the Chronic Renal Insufficiency Cohort Study

OBJECTIVE

Dietary interventions are the mainstay of chronic diseases prevention in general population, but the evidence to support such therapeutic approaches in patients with chronic kidney disease (CKD) is less robust. The objective of this study is to examine the association between dietary fiber intake and adverse cardiovascular and kidney outcomes and all-cause mortality in participants with CKD enrolled in the Chronic Renal Insufficiency Cohort study.

DESIGN AND METHODS

A total of 3791 Chronic Renal Insufficiency Cohort participants with self-reported dietary fiber intake were included in the analyses stratified by tertiles of dietary fiber at study baseline. Hazard ratios for occurrence of all-cause mortality, composite cardiovascular events and composite kidney events were calculated using Cox Proportional Hazards models adjusted for demographic, clinical, and laboratory characteristics, including levels of inflammatory markers, C-reactive protein and interleukin-6.

RESULTS

Mean daily dietary fiber intake was 15.2 g/day. During a median (standard deviation) follow up of 14.6 (4.4) years, 1074 deaths from any cause occurred. In multivariable adjusted models, participants in the middle and low dietary fiber tertiles had a 19% (hazard ratio [95% CI]), 1.19 [1.02, 1.39]) and 11% (1.11 [0.95, 1.31]) greater risk of death respectively, compared to those in the highest fiber intake tertile. No statistically significant associations were observed between dietary fiber intake and adverse cardiovascular and kidney outcomes. Higher dietary fiber intake was not significantly associated with lower levels of C-reactive protein and interleukin-6.

CONCLUSION

A lower intake of dietary fiber was not associated with all-cause mortality in participants with CKD after adjustments for kidney function and inflammatory biomarkers. There was no significant association between dietary fiber intake and adverse kidney and cardiovascular outcomes. Future randomized intervention trials are needed to identify whether a high dietary fiber intake translates into improved clinical outcomes in CKD.

Should a low-protein diet and ketoanalogue supplementation be part of the management of advanced chronic kidney disease?

The vast majority of patients with advanced chronic kidney disease (CKD) who transition to end-stage kidney disease (ESKD) are treated with dialysis. Given that dialysis does not always have the intended effects of increasing longevity and/or improving health, particularly in those with high comorbidity burden and/or older age groups, there has been increasing emphasis on interventions that delay or avert the need for renal replacement therapy. Among the multi-disciplinary approaches used to reduce CKD progression, dietary interventions are a major cornerstone. Current guidelines support the role of a low-protein diet in patients with moderate to advanced CKD who are metabolically stable. In addition to dietary protein amount, there is evidence that dietary protein sources as well as nutrients in plant-based foods have an important impact on kidney health outcomes. Clinical practice guidelines, including the 2020 National Kidney Foundation and Academy of Nutrition and Dietetics Kidney Disease Outcomes Quality Initiative Clinical Practice Guidelines for Nutrition in CKD, recommend a low protein diet for patients with moderate to advanced non-dialysis dependent (NDD)-CKD who are metabolically stable to reduce risk of ESKD and death. In addition to recommending lower protein intake, the recent 2024 Kidney Disease Improving Global Outcomes CKD Guidelines include a Practice Point advising that people with CKD eat more plant-based foods than animal-based foods. Increasing data also show that plant-based diets are associated with lower risk of progression of CKD and its complications including cardiovascular disease (cardio-kidney-metabolic syndrome), acid-base balance disorders, mineral bone disease, and dysglycemia.

Consensus Report on the Use of Continuous Glucose Monitoring in Chronic Kidney Disease and Diabetes

This report represents the conclusions of 15 experts in nephrology and endocrinology, based on their knowledge of key studies and evidence in the field, on the role of continuous glucose monitors (CGMs) in patients with diabetes and chronic kidney disease (CKD), including those receiving dialysis. The experts discussed issues related to CGM accuracy, indications, education, clinical outcomes, quality of life, research gaps, and barriers to dissemination. Three main goals of management for patients with CKD and diabetes were identified: (1) greater use of CGMs for better glycemic monitoring and management, (2) further research evaluating the accuracy, feasibility, outcomes, and potential value of CGMs in patients with end-stage kidney disease (ESKD) on hemodialysis, and (3) equitable access to CGM technology for patients with CKD. The experts also developed 15 conclusions regarding the use of CGMs in this population related to CGMs' unique delivery of both real-time information that can guide monitoring and management of glycemia and continuous and predictive data in this population, which is at higher risk for hypoglycemia and hyperglycemia. The group noted three major clinical gaps: (1) CGMs are not routinely prescribed for patients with diabetes and CKD; (2) CGMs are not approved by the United States Food and Drug Administration (FDA) for patients with diabetes who are on dialysis; and (3) CGMs are not routinely available to all of those who need them because of structural barriers in the health care system. These gaps can be improved with greater stakeholder collaboration, education, and awareness brought to the use of CGM technology in CKD.

Why protein-energy wasting leads to faster progression of chronic kidney disease

PURPOSE OF REVIEW

Protein-energy wasting (PEW) is increasingly more prevalent as chronic kidney disease (CKD) progresses to more advanced stages. There is a global recognition of the importance of preventing and mitigating PEW in the CKD population not on dialysis given the goal of extending dialysis-free time and delaying dialysis initiation and growing evidence of the clinical consequences of PEW which include the risk of death, hospitalization and clinical conditions such as infections. We reviewed the association of PEW and the malnutrition characteristics indicative of PEW on CKD progression.

RECENT FINDINGS

Studies show the association between low serum albumin levels, low BMI, and diets with inadequate dietary energy and protein intake and CKD progression. Limited studies suggest low muscle mass impacts CKD progression. Optimizing nutrition by dietary management, including a moderately low protein (0.6-0.8 g/kg/day) and plant-based (>50% of protein source, known as PLADO) diet and as needed with supplementation [e.g. during acute kidney injury (AKI) event] administrated orally, enterally, or parenterally are the basis for the prevention and treatment of PEW in CKD and delaying CKD progression. Furthermore, other therapeutic methods such as treating or avoiding comorbidities and AKI, ensuring appropriate exercise and incremental transition to dialysis treatment may help ameliorate and prevent PEW development in CKD patients.

SUMMARY

Using tailored precision nutrition approaches and nutritional supplementation with or without other beneficial strategies may help prevent and treat PEW and its consequent occurrence of CKD progression.

MyPlate Awareness and Engagement and Perceived and Objective Diet Quality in US Adults With Chronic Kidney Disease

OBJECTIVE

Awareness of federal dietary guidelines has been associated with better perceived and objective diet quality. Little is known about the awareness of federal dietary recommendations among persons with chronic kidney disease (CKD) and the associations between recognition of guidelines, perception of diet quality, and objective quality of the diet in this population.

DESIGN AND METHODS

We compared awareness of, and engagement with, MyPlate (a representation of 5 food groups from the US Department of Agriculture) along with perceived and objective diet quality, the latter assessed via Dietary Approaches to Stop Hypertension index scores, among US adults with and without CKD during 2017-2020.

RESULTS

Among noninstitutionalized adults in the United States, 8.3% had albuminuria with normal or near-normal kidney function, 4.0% had estimated glomerular filtration rate 45-59 mL/minute/1.73 m2 (CKD stage G3a) and 1.6% had estimated glomerular filtration rate <45 mL/minute/1.73 m2 (CKD stages G3b/G4/G5). MyPlate awareness was lower among persons with CKD compared with those without CKD (19.6% vs. 26.4%, P < .001) and was lower among persons with more advanced CKD stages: 20.8%, 18.2%, and 16.3% in persons with CKD stages G1/G2, G3a, and G3b/G4/G5, respectively (trend P < .001). Among persons aware of MyPlate, a numerically higher proportion with CKD attempted to follow MyPlate recommendations (43.9% vs. 32.3%, P = .10); the proportion was highest among persons with moderate-to-advanced CKD (41.9%, 42.9%, and 56.9% among persons with CKD stages G1/G2, G3a, and G3b/G4/G5, respectively (trend P < .001)). Perceived and objective dietary quality (the latter based on concordance with the Dietary Approaches to Stop Hypertension diet) were slightly higher among persons with CKD relative to those without CKD.

CONCLUSIONS

Adults with CKD have lower MyPlate awareness than adults without CKD. Enhancing diet education to persons with CKD could improve diet quality and potentially ameliorate CKD-associated complications.

A kidney-specific fasting-mimicking diet induces podocyte reprogramming and restores renal function in glomerulopathy

Cycles of a fasting-mimicking diet (FMD) promote regeneration and reduce damage in the pancreases, blood, guts, and nervous systems of mice, but their effect on kidney disease is unknown. In addition, a FMD has not been tested in rats. Here, we show that cycles of a newly developed low-salt FMD (LS-FMD) restored normal proteinuria and nephron structure and function in rats with puromycin-induced nephrosis compared with that in animals with renal damage that did not receive the dietary intervention. LS-FMD induced modulation of a nephrogenic gene program, resembling renal developmental processes in multiple kidney structures. LS-FMD also activated podocyte-lineage reprogramming pathways and promoted a quiescent state in mature podocytes in the rat kidney damage model. In a pilot clinical study in patients with chronic kidney disease, FMD cycles of 5 days each month for 3 months promoted renoprotection, including reduction of proteinuria and improved endothelial function, compared with that in patients who did not receive the FMD cycles. These results show that FMD cycles, which promote the reprogramming of multiple renal cell types and lead to glomerular damage reversal in rats, should be tested further for the treatment of progressive kidney diseases.

The Relevance of Phytate for the Treatment of Chronic Kidney Disease

Diets high in plant-based foods are commonly recommended for people with CKD. One putative advantage of these diets is reduced intestinal phosphate absorption. This effect has been ascribed to phytic acid (myoinositol hexaphosphoric acid) and its anion, phytate, that are present in many plant foods, particularly in the seeds, nuts, grains, and fruits of plants. This article reviews the structure and many actions of phytate with particular reference to its potential effects on people with CKD. Phytate binds avidly to and can reduce gastrointestinal absorption of the phosphate anion and many macrominerals and trace elements including iron, zinc, calcium, and magnesium. This has led some opinion leaders to label phytate as an anti-nutrient. The human intestine lacks phytase; hence, phytate is essentially not degraded in the small intestine. A small amount of phytate is absorbed from the small intestine, although phytate bound to phosphate is poorly absorbed. Clinical trials in maintenance hemodialysis patients indicate that intravenously administered phytate may decrease hydroxyapatite formation, vascular calcification, and calciphylaxis. Orally administered phytate or in vitro studies indicate that phytate may also reduce osteoporosis, urinary calcium calculi formation, and dental plaque formation. Phytate seems to have anti-inflammatory and antioxidant effects, at least partly because of its ability to chelate iron. Other potential therapeutic roles for phytate, not definitively established, include suppression of cancer formation, reduction in cognitive decline that occurs with aging, and amelioration of certain neurodegenerative diseases and several gastrointestinal and metabolic disorders. These latter potential benefits of phytate are supported by cell or animal research or observational studies in humans. Many of the above disorders are particularly common in patients with CKD. Definitive clinical trials to identify potential therapeutic benefits of phytate in patients with CKD are clearly warranted.

Personalized nutritional management in the transition from non-dialysis dependent chronic kidney disease to dialysis

Dialysis has been the dominant treatment regimen in end-stage kidney disease as a means to remove uremic waste products and to maintain electrolyte, acid base, and fluid balance. However, given that dialysis may not always provide a survival benefit nor improved quality of life in certain subpopulations, there is growing recognition of the need for conservative and preservative management as an alternative treatment strategy for advanced chronic kidney disease (CKD). Personalized nutritional management tailored to patient's sociodemographics, social needs, psychological status, health literacy level, and preferences is a key component of conservative and preservative care, as well as in the management of patients transitioning from non-dialysis dependent CKD to dialysis. In this review, we discuss the nutritional and metabolic alterations that ensue in CKD; the rationale for low-protein diets in the conservative and preservative management of advanced CKD; the role of plant-based diets in kidney health; emerging data on dietary potassium and sodium intake on CKD outcomes; and the practical implementation of dietary interventions in advanced kidney disease.

Precision nutrition-based strategy for management of human diseases and healthy aging: current progress and challenges forward

Currently, the treatment of various human ailments is based on different therapeutic approaches including traditional and modern medicine systems. Precision nutrition has come into existence as an emerging approach considering the diverse aspects such as age, sex, genetic and epigenetic makeup, apart from the pathophysiological conditions. The continuously and gradually evolving disciplines of genomics about nutrition have elucidated the importance of genetic variations, epigenetic information, and expression of myriads of genes in disease progression apart from the involvement in modulating therapeutic responses. Further, the investigations have presented the considerable role of gut microbiota comprising of commensal and symbionts performing innumerable activities such as release of bioactive molecules, defense against pathogenic microbes, and regulation of immunity. Noteworthy, the characteristics of the microbiome change depending on host attributes, environmental factors, and habitat, in addition to diet, and therefore can be employed as a biomarker to unravel the response to given food. The specific diet and the components thereof can be suggested for supporting the enrichment of the desired microbial community to some extent as an important part of precision nutrition to achieve not only the goal of human health but also of healthy aging.

Causal factors of cardiovascular disease in end-stage renal disease with maintenance hemodialysis: a longitudinal and Mendelian randomization study

Background

The risk factors of cardiovascular disease (CVD) in end-stage renal disease (ESRD) with hemodialysis remain not fully understood. In this study, we developed and validated a clinical-longitudinal model for predicting CVD in patients with hemodialysis, and employed Mendelian randomization to evaluate the causal 6study included 468 hemodialysis patients, and biochemical parameters were evaluated every three months. A generalized linear mixed (GLM) predictive model was applied to longitudinal clinical data. Calibration curves and area under the receiver operating characteristic curves (AUCs) were used to evaluate the performance of the model. Kaplan-Meier curves were applied to verify the effect of selected risk factors on the probability of CVD. Genome-wide association study (GWAS) data for CVD (n = 218,792,101,866 cases), end-stage renal disease (ESRD, n = 16,405, 326 cases), diabetes (n = 202,046, 9,889 cases), creatinine (n = 7,810), and uric acid (UA, n = 109,029) were obtained from the large-open GWAS project. The inverse-variance weighted MR was used as the main analysis to estimate the causal associations, and several sensitivity analyses were performed to assess pleiotropy and exclude variants with potential pleiotropic effects.

Results

The AUCs of the GLM model was 0.93 (with accuracy rates of 93.9% and 93.1% for the training set and validation set, sensitivity of 0.95 and 0.94, specificity of 0.87 and 0.86). The final clinical-longitudinal model consisted of 5 risk factors, including age, diabetes, ipth, creatinine, and UA. Furthermore, the predicted CVD response also allowed for significant (p < 0.05) discrimination between the Kaplan-Meier curves of each age, diabetes, ipth, and creatinine subclassification. MR analysis indicated that diabetes had a causal role in risk of CVD (β = 0.088, p < 0.0001) and ESRD (β = 0.26, p = 0.007). In turn, ESRD was found to have a causal role in risk of diabetes (β = 0.027, p = 0.013). Additionally, creatinine exhibited a causal role in the risk of ESRD (β = 4.42, p = 0.01).

Conclusions

The results showed that old age, diabetes, and low level of ipth, creatinine, and UA were important risk factors for CVD in hemodialysis patients, and diabetes played an important bridging role in the link between ESRD and CVD.

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

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

Workforce needs and estimated costs/savings for nutrition care in chronic kidney disease-stage 3 through maintenance dialysis

The role of nutrition in chronic kidney disease (CKD) is well known. However, controversies, misconceptions, and gaps in the literature exist regarding the workforce required to provide nutrition care in CKD. This paper reviews the existing literature on this topic, focusing primarily on the United States. Topics covered in this review include the qualifications and services of the registered dietitian nutritionist (RDN), to which specific patients nutrition care should be provided in CKD and on dialysis, barriers to the utilization of nutrition services, the quantity of nutrition care needed to improve patient outcomes, and the risks of provider burnout. Controversies include whether more staffing is associated with better care and the best measures of staffing. The topics are supported with estimations for the economic impact and practicality of workforce decisions.

Preventing potential pitfalls of a liberalized potassium diet in the hemodialysis population

Emerging research suggests that a more liberalized diet, specifically a more plant-based diet resulting in liberalization of potassium intake, for people receiving hemodialysis is necessary and the benefits outweigh previously thought risks. If the prescribed hemodialysis diet is to be liberalized, the need to illuminate and prevent potential pitfalls of a liberalized potassium diet is warranted. This paper explores such topics as partial to full adherence to a liberalized diet and its consequences if any, the advantages of a high-fiber intake, the theoretical risk of anemia when consuming a more plant-dominant diet, the potential benefits against renal acid load and effect on metabolic acidosis with increased fruit and vegetable intake, the putative change in serum potassium levels, carbohydrate quality, and the healthfulness of meat substitutes. The benefits of a more plant-based diet for the hemodialysis population are multifold; however, the possible pitfalls of this type of diet must be reviewed and addressed upon meal planning in order to be avoided.

A study of the low-protein diet in delaying the course of chronic kidney disease

A low-protein diet (LPD) has become an important way to delay the progression of chronic kidney disease (CKD) and to delay the need for dialysis. A review of the literature reveals the low-protein diet's influence on the course of chronic kidney disease. An artificial low-protein food, wheat starch, for example, can not only increase the high-quality protein intake ratio, but can ensure adequate energy intake on a low-protein diet while meeting the nutritional needs of the body, effectively reducing the burden on the damaged kidneys. The purpose of this review is to provide a reference for the clinical implementation of diet and nutrition therapy in patients with chronic kidney disease.

Metabolomic and Physiological Effects of a Cardiorenal Protective Diet Intervention in African American Adults with Chronic Kidney Disease

Chronic kidney disease (CKD) impacts 14% of adults in the United States, and African American (AA) individuals are disproportionately affected, with more than 3 times higher risk of kidney failure as compared to White individuals. This study evaluated the effects of base-producing fruit and vegetables (FVs) on cardiorenal outcomes in AA persons with CKD and hypertension (HTN) in a low socioeconomic area. The "Cardiorenal Protective Diet" prospective randomized trial evaluated the effects of a 6-week, community-based FV intervention compared to a waitlist control (WL) in 91 AA adults (age = 58.3 ± 10.1 years, 66% female, 48% income ≤ USD 25K). Biometric and metabolomic variables were collected at baseline and 6 weeks post-intervention. The change in health outcomes for both groups was statistically insignificant (p > 0.05), though small reductions in albumin to creatinine ratio, body mass index, total cholesterol, and systolic blood pressure were observed in the FV group. Metabolomic profiling identified key markers (p < 0.05), including C3, C5, 1-Met-His, kynurenine, PC ae 38:5, and choline, indicating kidney function decline in the WL group. Overall, delivering a directed cardiorenal protective diet intervention improved cardiorenal outcomes in AA adults with CKD and HTN. Additionally, metabolomic profiling may serve as a prognostic technique for the early identification of biomarkers as indicators for worsening CKD and increased CVD risk.

Effects of Cranberry Extract (Vaccinium macrocarpon) Supplementation on Lipid Peroxidation and Inflammation in Patients with Chronic Kidney Disease (Stages 3-4): A Randomized Controlled Trial

Background

Growing evidence suggests that bioactive compounds in berry fruits may mitigate inflammation in patients with chronic kidney disease (CKD).

Objectives

To evaluate cranberry (Vaccinium macrocarpon) supplementation effects on modulation of transcription factors involved in inflammation and oxidative stress in nondialysis (stages 3 and 4) patients with CKD. Design/Participants. A randomized, double-blind, placebo-controlled study was performed with 30 patients to receive capsules containing cranberry extract (1000 mg/day) or placebo (1000 mg/day of corn starch) for two months. Measurements. The mRNA expression of nuclear factor-erythroid 2-related factor-2 (Nrf2) and nuclear factor-kB (NF-kB) was evaluated in peripheral blood mononuclear cells (PBMCs) by quantitative real-time polymerase chain reaction. Thiobarbituric acid reactive substances (TBARS) were measured in the plasma to assess oxidative stress. Interleukin-6 (IL-6) plasma levels were assessed by enzyme-linked immunosorbent assay and C-reactive protein (CRP) by immunoturbidimetric method.

Results

Twenty-five patients completed the study: 12 in the cranberry group (56.7 ± 7.5 years and body mass index (BMI) of 29.6 ± 5.5 kg/m2) and 13 in the placebo group (58.8 ± 5.1 years and BMI 29.8 ± 5.4 kg/m2). There were no differences in NF-kB or Nrf2 mRNA expressions (p = 0.99 and p = 0.89) or TBARS, CRP, and IL-6 plasma levels after cranberry supplementation.

Conclusions

The cranberry extract administration (1000 mg/day) did not affect Nrf2 and NF-kB mRNA expression, oxidative stress, or inflammatory markers levels in nondialysis CKD patients. This trial is registered with NCT04377919.

A Therapeutic Approach in the Management of Chronic Kidney Disease: Plant-Based Dietary Models and Associated Parameters

PURPOSE OF REVIEW

Chronic kidney disease is one of the leading causes of death worldwide today. Nutrition and nutrition-related factors have a very important role in both the prevention and management of the disease. Plant-based dietary practices are one of the promising approaches to chronic kidney disease. This review aims to examine the potential benefits and risks of plant-based diet models on symptoms and indices used in diet quality in chronic kidney disease.

RECENT FINDINGS

Recently, a growing body of evidence has shown that, unlike animal-based diets, diets rich in plant-based nutrients may play an active role in the incidence of chronic kidney disease in many ways and the management of common symptoms, such as metabolic acidosis, uremic toxicity, and hyperphosphatemia. Implementation of existing plant-based dietary patterns in patients with chronic kidney disease may increase the efficacy of the diet and improve patients' quality of life by expanding their food choices. While there are concerns about creatine deficiency, dietary adequacy, and accessibility regarding plant-based diets, available information is limited.

Current perspective on circadian function of the kidney

Behavior and function of living systems are synchronized by the 24-h rotation of the Earth that guides physiology according to time of day. However, when behavior becomes misaligned from the light-dark cycle, such as in rotating shift work, jet lag, and even unusual eating patterns, adverse health consequences such as cardiovascular or cardiometabolic disease can arise. The discovery of cell-autonomous molecular clocks expanded interest in regulatory systems that control circadian physiology including within the kidney, where function varies along a 24-h cycle. Our understanding of the mechanisms for circadian control of physiology is in the early stages, and so the present review provides an overview of what is known and the many gaps in our current understanding. We include a particular focus on the impact of eating behaviors, especially meal timing. A better understanding of the mechanisms guiding circadian function of the kidney is expected to reveal new insights into causes and consequences of a wide range of disorders involving the kidney, including hypertension, obesity, and chronic kidney disease.

Plant-based diets in patients with chronic kidney disease

Dietary protein restriction has been considered to be a nutritional-related strategy to reduce risk for end-stage kidney disease among patients with non-dialysis-dependent chronic kidney disease (CKD). However, there is insufficient evidence to recommend a particular type of protein to slow down the CKD progression. Recently, various plant-based diets could demonstrate some additional benefits such as a blood pressure-lowering effect, a reduction of metabolic acidosis as well as hyperphosphatemia, and gut-derived uremic toxins. Furthermore, the former concerns about the risk of undernutrition and hyperkalemia observed with plant-based diets may be inconsistent in real clinical practice. In this review, we summarize the current evidence of the proposed pleiotropic effects of plant-based diets and their associations with clinical outcomes among pre-dialysis CKD patients.

Ketogenic metabolic therapy for chronic kidney disease - the pro part

Ketogenic metabolic therapy (KMT) is a medical nutrition therapy to address certain health and disease conditions. It is increasingly used for many non-communicable diseases that are rooted in abnormal metabolic health. Since chronic kidney disease (CKD) is commonly caused by overnutrition leading to hyperglycemia, insulin resistance and diabetes mellitus, the carbohydrate restriction inherent in KMT may offer a therapeutic option. Numerous studies have found that various forms of KMT are safe for individuals with CKD and may lead to improvement of renal function. This is in contrast to the current standard pharmacological approach to CKD that only slows the relentless progression towards renal failure. Kidney care providers, including physicians and dietitians, are usually not aware of non-standard dietary interventions, including KMT, and often criticize KMT due to common misconceptions and uncertainty about the underlying science, including the common misconception that KMT must involve high protein or meat consumption. This review article discusses the rationales for using KMT, including plant-dominant KMT, for treatment of CKD, clarifies common misconceptions, summarizes the results of clinical studies and discusses why KMT is emerging as an effective medical nutrition therapy (MNT) to consider for patients with kidney disease. KMT, including its plant-dominant versions, can expand a practitioner's kidney health toolbox and will likely become a first-line therapy for CKD in certain CKD-associated conditions such as obesity, metabolic syndrome and polycystic kidney disease.

Dietary protein intake and plant-dominant diets to mitigate risk of allograft dysfunction progression in kidney transplant recipients

PURPOSE OF REVIEW

There are limited studies on the benefits of low dietary protein intake (DPI) and plant-dominant diets to delay kidney allograft dysfunction. We evaluate evidence regarding the association or effects of the amount and type of DPI on allograft function.

RECENT FINDINGS

There is conflicting evidence regarding the benefits of low DPI and plant-dominant diet including PLADO and PLAFOND on kidney allograft function. Taking the strength of evidence including study design, sample size, and time to follow-up, the proposed amount of DPI to slow the progression of allograft dysfunction, avoid negative nitrogen balance, and skeletal muscle mass loss is 1.0-1.3 g/kg/day during an immediate posttransplant period or when high protein catabolic rate exists. The DPI may be 0.8-1.0 g/kg/day in patients with stable allograft function. Patients with chronic allograft rejection or estimated glomerular filtration rate <25 ml/min may benefit from the DPI of 0.55-0.60 g/kg/day, while those with failed allograft requiring transition to dialysis including incremental (twice-weekly) hemodialysis should consider increasing DPI to 1.0-1.2 g/kg/day.

SUMMARY

While there is a lack of strong evidence, individualized approaches based on the patient's comorbidities, net state of immunosuppression, and periods posttransplant may guide the appropriate amount and type of DPI to slow allograft dysfunction.

Climate crisis and nephrology: a review of climate change's impact on nephrology and how to combat it

Climate change is worsening with tangible effects on our healthcare system. This review aims to examine the repercussions of the climate change on nephrology and explore potential strategies to mitigate its impact. This review examines dialysis's environmental impact, resource recycling methods, and plant-based diets for kidney health. Recent research highlights the advantages of plant-based diets in managing and preventing chronic kidney disease (CKD) and its complications. Integrating these practices can significantly lessen the environmental impact of nephrology.

PURPOSE OF REVIEW

The aim of this study is to discuss the bidirectional relationship of climate change and kidney disease and the impact of nephrology on climate change and to discuss potential solutions.

RECENT FINDINGS

Each dialysis session consumes significant amounts of resource; reusing them will aid the environment. Plant-based diets slow renal disease and have a lower carbon footprint, making them ecologically friendly.

SUMMARY

Climate change is a growing threat to population health and healthcare. Rising temperatures raise the risk of kidney problems. Dialysis treatments also impact the environment through its high resource requirements while generating high volumes of waste and greenhouse gases. Opportunities exist to reduce the environmental impact of dialysis treatments. Plant-based diets serve to benefit both kidney disease and the environment.

Risks of the ketogenic diet in CKD - the con part

The ketogenic diet is a very low carbohydrate diet that has received a lot of attention for its role in the treatment of type 2 diabetes and obesity. For patients with chronic kidney disease, there is limited evidence on the risks and/or benefits of this diet. However, from the limited evidence that does exist, there are several inferences that can be drawn regarding this diet for patients with kidney disease. The ketogenic diet may not be better than comparator higher carbohydrate diets over the long term. The diet also has low adherence levels in studies lasting ≥12 months. The diet's emphasis on fat, which often comes from animal fat, increases the consumption of saturated fat, which may increase the risk of heart disease. It has the potential to worsen metabolic acidosis by increasing dietary acid load and endogenous acid production through the oxidation of fatty acids. In addition, the diet has been associated with an increased risk of kidney stones in patients using it for the treatment of refractory epilepsy. For these reasons, and for the lack of safety data on it, it is reasonable for patients with kidney disease to avoid utilizing the ketogenic diet as a first-line option given alternative dietary patterns (like the plant-dominant diet) with less theoretical risk for harm. For those adopting the ketogenic diet in kidney disease, a plant-based version of the ketogenic diet may mitigate some of the concerns with animal-based versions of the ketogenic diet.

Cystatin C as a GFR Estimation Marker in Acute and Chronic Illness: A Systematic Review

Rationale & Objective

Creatinine-based GFR estimating (eGFRcr) equations may be inaccurate in populations with acute or chronic illness. The accuracy of GFR equations that use cystatin C (eGFRcys) or creatinine-cystatin C (eGFRcr-cys) is not well studied in these populations.

Study Design

A systematic review of original articles identified from PubMed and expert sources. Two reviewers screened articles independently and identified those meeting inclusion criteria.

Setting & Study Populations

Adults and children with acute or chronic illness.

Selection Criteria for Studies

Studies published since 2011 that compared performance of eGFRcr, eGFRcys, and eGFRcr-cys relative to measured GFR (mGFR), used standardized assays for creatinine or cystatin C, and used eGFR equations developed using such assays. Studies of ambulatory clinical populations or research studies in populations with only CKD, kidney transplant recipients, only diabetes, kidney donor candidates, and community-based cohorts were excluded.

Data Extraction

Data extracted from full text.

Analytical Approach

Bias and percentages of estimates within 30% of mGFR (P30) of eGFR compared with mGFR were evaluated.

Results

Of the 179 citations, 26 studies met the inclusion criteria: 24 in adults and 2 in children in clinical populations with cancer (n=5), HIV (n=5), cirrhosis (n=3), liver transplant (n=3), heart failure (n=2), neuromuscular diseases (n=1) critical illness (n=5), and obesity (n=2). In general, eGFRcr-cys had greater accuracy than eGFRcr or eGFRcys equations among study populations with cancer, HIV, and obesity, but did not perform consistently better in cirrhosis, liver transplant, heart failure, neuromuscular disease, and critical illness.

Limitations

Participants were selected because of concern for inaccurate eGFRcr, which may bias results. Most studies had small sample sizes, limiting generalizability.

Conclusions

eGFRcr-cys improves GFR estimation in populations with a variety of acute and chronic illnesses, providing indications for cystatin C measurement. Performance was poor in many studies, suggesting the need for more frequent mGFR.

Plain-Language Summary

Kidney function, specifically glomerular filtration rate (GFR), estimated using creatinine (eGFRcr) is often inaccurate in people with acute and chronic illness. The accuracy of estimates using cystatin C alone (eGFRcys) or together with creatinine (eGFRcr-cys) is not well studied in these populations. We conducted a systematic review to address the knowledge gap. Of the 179 papers reviewed, we identified 26 studies in clinical populations with cancer (n=5); HIV (n=5); cirrhosis (n=3); liver transplant (n=3); heart failure (n=2); neuromuscular disease (n=1); critical illness (n=5); and obesity (n=2). In general, eGFRcr-cys improved the GFR estimation in HIV, cancer, and obesity, providing indications for cystatin C measurement. Performance was poor in many studies, suggesting the need for more frequent measured GFR.

Overview of research progress on the association of dietary potassium intake with serum potassium and survival in hemodialysis patients, does dietary potassium restriction really benefit hemodialysis patients?

For the general population, increasing potassium intake can reduce the incidence of cardiovascular and cerebrovascular diseases. However, since hyperkalemia is a common and life-threatening complication in maintenance hemodialysis patients, which can increase the risk of malignant arrhythmia and sudden death, the current mainstream of management for hemodialysis patients is dietary potassium restriction in order to prevent hyperkalemia. Hemodialysis patients are usually advised to reduce dietary potassium intake and limit potassium-rich fruits and vegetables, but there is limited evidence to support this approach can reduce mortality and improve quality of life. There is still no consistent conclusion on the association between dietary potassium intake and serum potassium and survival in hemodialysis patients. According to the current small observational studies, there was little or even no association between dietary potassium intake and serum potassium in hemodialysis patients when assurance of adequate dialysis and specific dietary patterns (such as the plant-based diet mentioned in the article) are being followed, and excessive dietary potassium restriction may not benefit the survival of hemodialysis patients. Additionally, when assessing the effect of diet on serum potassium, researchers should not only focus on the potassium content of foods, but also consider the type of food and the content of other nutrients. However, more large-scale, multi-center clinical trials are required to provide high-quality evidence support. Besides, further research is also needed to determine the optimal daily potassium intake and beneficial dietary patterns for hemodialysis patients.

Plant-based diets: a fad or the future of medical nutrition therapy for children with chronic kidney disease?

Plant-based diets are growing in popularity worldwide due to the importance of reducing the population's ecological footprint as well as an emerging role in the prevention and treatment of chronic human diseases. In adults, plant-based diets have been shown to be beneficial for preventing and controlling conditions that are common in patients with chronic kidney disease (CKD), such as obesity, hypertension, type 2 diabetes, dyslipidemia, and metabolic acidosis. Emerging evidence suggests that the higher fiber content of plant-based diets may help to modulate production of uremic toxins through beneficial shifts in the gut microbiome. The effects of the plant-based diet on progression of CKD remain controversial, and there are no data to support this in children. However, knowledge that the bioavailability of potassium and phosphorus from plant-based foods is reduced has led to recent changes in international kidney-friendly diet recommendations for children with CKD. The new guidelines advise that high potassium fruits and vegetables should no longer be automatically excluded from the kidney-friendly diet. In fact, a plant-based diet can be safely implemented in children with CKD through building the diet around whole, high fiber foods, avoiding processed foods and using recommended cooking methods to control potassium. The health benefits of the plant-based diet compared to omnivorous diets in children with CKD need investigation.

Effects of Plant-Based Protein Consumption on Kidney Function and Mineral Bone Disorder Outcomes in Adults With Stage 3-5 Chronic Kidney Disease: A Systematic Review

INTRODUCTION

Plant-based protein is of growing interest for dietary management of chronic kidney disease (CKD) and is hypothesized to preserve kidney function and reduce CKD-mineral bone disorder (MBD) complications, among other benefits. This systematic review aimed to summarize the available clinical trial evidence for the effect of plant-based protein on kidney function and CKD-MBD outcomes in adults with stage 3-5 CKD not on dialysis.

METHODS

Searches of Medline, Embase, Agricola, CAB abstracts, Web of Science, Scopus, and hand searching were performed. Clinical trials with ≥8 participants ≥18 years of age with an estimated glomerular filtration rate <60 mL/min/1.73 m2 but not on dialysis were included. Additionally, only clinical trials with ≥1-week interventions with ≥50% dietary protein from plant-based sources and reported at least one outcome for both kidney function and CKD-MBD outcomes were included. Of the 10,962 identified abstracts, 32 met inclusion criteria and were assessed for risk of bias.

RESULTS

Results for kidney function and CKD-MBD outcomes were heterogenous, with most studies having suboptimal methodological quality. In most of the studies (27/32), protein source was altered only secondarily to low-protein diet interventions. Thus, data synthesis and interpretation were focused on a subset of five studies that investigated a change in protein source only (i.e., animal vs. plant). Of this subset, four studies reported no change in kidney function, while one study reported a decrease. Three studies reported no change in serum phosphorus, and one study reported lower serum phosphorus following a vegetarian diet. Further, limited data and inconclusive results were observed for phosphaturic hormones, parathyroid hormone, and fibroblast growth factor-23.

CONCLUSION

Current clinical trial evidence on plant-based protein interventions for preserving kidney function and preventing CKD-MBD is limited to inform clinical guidelines at this time. This systematic review emphasizes the ongoing need to research the effects of plant-based protein on kidney function and CKD-MBD outcomes.

A Low-Protein, Plant-Dominant Gluten-Free Diet for Immunoglobulin A Nephropathy and Focal Segmental Glomerulosclerosis

Immunoglobulin A nephropathy is the most common glomerulonephritis syndrome in the world, yet there is currently no cure. While blood pressure control, renin-angiotensin-aldosterone system inhibition, and immunosuppression may slow disease progression, low-protein diets, defined as a daily dietary protein intake of 0.6 to 0.8 g/kg body weight, may also decrease immune complex deposition and disease severity, as evidenced in animal models. The link between secondary immunoglobulin A nephropathy and celiac disease has also led to the rise of gluten-free diets and zinc supplementation as potential lifestyle modifications to help manage common immunoglobulin A nephropathy symptoms such as proteinuria and hematuria. In addition, case reports and prospective studies suggest that patients with focal segmental glomerulosclerosis, which manifests as steroid-resistant nephrotic syndrome may also benefit from a gluten-free diet. We highlight the example of a gluten-free, plant-dominant low-protein diet (a different type of low-protein diet that addresses both protein quantity and quality) for patients with immunoglobulin A nephropathy or focal segmental glomerulosclerosis.

Management of traditional risk factors for the development and progression of chronic kidney disease

Chronic kidney disease (CKD) and its downstream complications (i.e. cardiovascular) are a major source of morbidity worldwide. Additionally, deaths due to CKD or CKD-attributable cardiovascular disease account for a sizeable proportion of global mortality. However, the advent of new pharmacotherapies, diagnostic tools, and global initiatives are directing greater attention to kidney health in the public health agenda, including the implementation of effective strategies that (i) prevent kidney disease, (ii) provide early CKD detection, and (iii) ameliorate CKD progression and its related complications. In this Review, we discuss major risk factors for incident CKD and CKD progression categorized across cardiovascular (i.e. hypertension, dyslipidemia, cardiorenal syndrome), endocrine (i.e. diabetes mellitus, hypothyroidism, testosterone), lifestyle (i.e. obesity, dietary factors, smoking), and genetic/environmental (i.e. CKDu/Mesoamerican nephropathy, APOL1, herbal nephropathy) domains, as well as scope, mechanistic underpinnings, and management.

Association of Plant-Based Protein Intake with Cognitive Function in Adults with CKD

Key Points

Higher plant protein intake was associated with higher cognitive scores in people with kidney disease. Future trials are needed to determine whether increasing plant protein intake improves measures of cognition in patients with kidney disease.

Background

Patients with CKD have accelerated cardiovascular and cognitive aging when compared with the non-CKD population. This cognitive decline contributes to excessive rates of physical and functional decline, reduced quality of life, and mortality in the CKD population. Mediterranean diets, a plant-forward diet, have been associated with positive cognitive performance in the general non-CKD population and with some beneficial outcomes in CKD. However, it is still unclear whether plant-based diets are associated with cognitive decline in patients with CKD.

Methods

Using the National Health and Nutrition Examination Survey 2011–2012 and 2013–14 data, we conducted a secondary analysis evaluating the relationship of plant-based and unprocessed plant protein with cognitive outcome measures in eligible participants aged 60 years and older. All data were extracted from the available National Health and Nutrition Examination Survey demographic, questionnaire, examination, and laboratory data. CKD was calculated and defined in participants as urine albumin to creatinine ratio ≥30 mg/g and/or eGFR <60 ml/min. In incremental models, we adjusted for total energy intake, age, sex, race/ethnicity, body mass index, total energy intake, diabetes, hypertension, education, smoking, and alcohol.

Results

Higher plant-based protein above median dietary intakes was significantly associated with higher executive function scores in participants with CKD (P < 0.05). For all patients and in those with CKD, plant-based protein was significantly associated (P < 0.05) with higher composite cognitive scores in nearly all statistical models. Higher unprocessed plant protein was significantly associated (P < 0.05) with higher composite cognitive scores in all categorical models.

Conclusions

Higher plant protein intake was a significant predictor of certain individual and composite cognitive score measures within the general and in the CKD population. Future interventional trials are needed to determine whether increasing plant-based protein intake improves measures of cognition in patients with CKD.

Low-Protein Diets and Its Synergistic Role in the SGLT2 Inhibitor Era

Low-protein diets (LPDs), usually defined as a daily dietary protein intake of 0.6 to 0.8 g/kg body weight, have been recommended for decades as a safe and effective lifestyle modification to ameliorate inflammatory damage and proteinuria, reduce glomerular hyperfiltration, and improve metabolic acidosis control in patients with chronic kidney disease (CKD). The mechanism for this is largely attributed to altered tubuloglomerular feedback and afferent arteriole contraction leading to decreased glomerular pressure. Additionally, low protein intake reduces urea generation, which can help delay dialysis initiation in advanced CKD. LPDs have different types including plant-dominant LPDs that can exert additional kidney protective effects as a result of dietary protein quality in addition to quantity. In addition, strong clinical evidence shows that a new class of diabetes mellitus medications, the sodium-glucose cotransporter 2 inhibitors, reduces albuminuria and slows the estimated glomerular filtration rate decline in CKD, even in patients without diabetes mellitus, especially if significant proteinuria is present. Given prior studies investigating the effect of LPDs used in conjunction with angiotensin pathway modulators, we argue that LPDs have a synergistic role in disease management and are expected to display additive effects when combined with sodium-glucose cotransporter 2 inhibitor usage or other pharmacologic agents. Even with medical therapy, it is prudent to implement tailored LPDs for different types of CKD.

Easy Kidney-Healthy Recipes

As the diet for people with CKD changes based on new clinical trials, patients are not clear on how to accurately use their diet to protect their kidneys or best manage their electrolytes if they are on dialysis. They often make restrictions where they shouldn't and miss the dietary interventions that could actually make a difference. In this article, I present four recipes that can be tailored to any stage of kidney disease. They are low in sodium, easy to make at home, and can be adapted to low phosphorus, low protein, or low potassium diets as needed.

Nutritional and Dietary Management of Chronic Kidney Disease Under Conservative and Preservative Kidney Care Without Dialysis

While dialysis has been the prevailing treatment paradigm for patients with advanced chronic kidney disease (CKD), emphasis on conservative and preservative management in which dietary interventions are a major cornerstone have emerged. Based on high-quality evidence, international guidelines support the utilization of low-protein diets as an intervention to reduce CKD progression and mortality risk, although the precise thresholds (if any) for dietary protein intake vary across recommendations. There is also increasing evidence demonstrating that plant-dominant low-protein diets reduce the risk of developing incident CKD, CKD progression, and its related complications including cardiometabolic disease, metabolic acidosis, mineral and bone disorders, and uremic toxin generation. In this review, we discuss the premise for conservative and preservative dietary interventions, specific dietary approaches used in conservative and preservative care, potential benefits of a plant-dominant low-protein diet, and practical implementation of these nutritional strategies without dialysis.

Food Insecurity and Chronic Kidney Disease: Considerations for Practitioners

The coronavirus disease 2019 pandemic has exacerbated existing health disparities related to food security status. Emerging literature suggests individuals with Chronic Kidney Disease (CKD) who are also food insecure have a greater likelihood of disease progression compared to food secure individuals. However, the complex relationship between CKD and food insecurity (FI) is understudied relative to other chronic conditions. The purpose of this practical application article is to summarize the recent literature on the social-economic, nutritional, to care through which FI may negatively impact health outcomes in individuals with CKD. While several studies have reported on the cross-sectional prevalence of FI among persons with CKD, literature is lacking about the severity and duration of exposure to FI on CKD outcomes. Future research is needed to better understand how FI impairs CKD care, nutritional and structural barriers that impact disease prevention and disease progression, and effective strategies to support patients.

Derivation and elimination of uremic toxins from kidney-gut axis

Uremic toxins are chemicals, organic or inorganic, that accumulate in the body fluids of individuals with acute or chronic kidney disease and impaired renal function. More than 130 uremic solutions are included in the most comprehensive reviews to date by the European Uremic Toxins Work Group, and novel investigations are ongoing to increase this number. Although approaches to remove uremic toxins have emerged, recalcitrant toxins that injure the human body remain a difficult problem. Herein, we review the derivation and elimination of uremic toxins, outline kidney-gut axis function and relative toxin removal methods, and elucidate promising approaches to effectively remove toxins.

Personalized Flexible Meal Planning for Individuals With Diet-Related Health Concerns: System Design and Feasibility Validation Study

BACKGROUND

Chronic diseases such as heart disease, stroke, diabetes, and hypertension are major global health challenges. Healthy eating can help people with chronic diseases manage their condition and prevent complications. However, making healthy meal plans is not easy, as it requires the consideration of various factors such as health concerns, nutritional requirements, tastes, economic status, and time limits. Therefore, there is a need for effective, affordable, and personalized meal planning that can assist people in choosing food that suits their individual needs and preferences.

OBJECTIVE

This study aimed to design an artificial intelligence (AI)-powered meal planner that can generate personalized healthy meal plans based on the user's specific health conditions, personal preferences, and status.

METHODS

We proposed a system that integrates semantic reasoning, fuzzy logic, heuristic search, and multicriteria analysis to produce flexible, optimized meal plans based on the user's health concerns, nutrition needs, as well as food restrictions or constraints, along with other personal preferences. Specifically, we constructed an ontology-based knowledge base to model knowledge about food and nutrition. We defined semantic rules to represent dietary guidelines for different health concerns and built a fuzzy membership of food nutrition based on the experience of experts to handle vague and uncertain nutritional data. We applied a semantic rule-based filtering mechanism to filter out food that violate mandatory health guidelines and constraints, such as allergies and religion. We designed a novel, heuristic search method that identifies the best meals among several candidates and evaluates them based on their fuzzy nutritional score. To select nutritious meals that also satisfy the user's other preferences, we proposed a multicriteria decision-making approach.

RESULTS

We implemented a mobile app prototype system and evaluated its effectiveness through a use case study and user study. The results showed that the system generated healthy and personalized meal plans that considered the user's health concerns, optimized nutrition values, respected dietary restrictions and constraints, and met the user's preferences. The users were generally satisfied with the system and its features.

CONCLUSIONS

We designed an AI-powered meal planner that helps people create healthy and personalized meal plans based on their health conditions, preferences, and status. Our system uses multiple techniques to create optimized meal plans that consider multiple factors that affect food choice. Our evaluation tests confirmed the usability and feasibility of the proposed system. However, some limitations such as the lack of dynamic and real-time updates should be addressed in future studies. This study contributes to the development of AI-powered personalized meal planning systems that can support people's health and nutrition goals.

Should Men Eat More Plants? A Systematic Review of the Literature on the Effect of Plant-Forward Diets on Men's Health

OBJECTIVE

To perform a systematic review of the literature on plant-based and plant-forward diets and the prevention/treatment of the following common men's health conditions: prostate cancer (PCa), erectile dysfunction (ED), and benign prostatic hyperplasia (BPH).

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses system criteria were utilized to search PubMed and Medline databases for the following search terms: "Diet (Mesh)" OR "Diet Therapy (Mesh)" AND "Prostatic Hyperplasia (Mesh)" OR "Prostatic Neoplasm (Mesh)" OR "Erectile Dysfunction (Mesh)." Articles in English published from 1989 to 2022 using human participants were analyzed, data summarized, and assessed for bias.

RESULTS

Studies reporting on plant-based or vegetable-forward diets (Mediterranean) as an intervention were included. Cohort and cross-sectional studies using food frequency questionnaires or diet classification indices to quantify plant-based food intake patterns were included in the study. Ultimately, 12 PCa articles, 4 BPH articles, 6 ED articles, and 2 articles related to both BPH and ED were reviewed. Overall, the literature suggests plant-forward diets confer a protective effect on the men's health conditions reviewed.

CONCLUSIONS

Evaluation of the literature on the impact of plant-forward diets on urologic conditions includes a heterogenous range of dietary patterns and study designs. The greatest amount of research has evaluated the application of plant-forward diets for PCa. While there is currently a lack of high-quality evidence for the use of plant-forward diets as prevention and/or treatment for PCa, ED, or BPH, reported outcomes suggest a consistent small beneficial impact alongside well-established benefits for common chronic conditions.

Proteinuria Modifies the Relationship Between Urinary Sodium Excretion and Adverse Kidney Outcomes: Findings From KNOW-CKD

Introduction

High sodium intake is associated with increased proteinuria. Herein, we investigated whether proteinuria could modify the association between urinary sodium excretion and adverse kidney outcomes in patients with chronic kidney disease (CKD).

Methods

In this prospective observational cohort study, we included 967 participants with CKD stages G1 to G5 between 2011 and 2016, who measured 24-hour urinary sodium and protein excretion at baseline. The main predictors were urinary sodium and protein excretion levels. The primary outcome was CKD progression, which was defined as a ≥50% decline in the estimated glomerular filtration rate (eGFR) or the onset of kidney replacement therapy.

Results

During a median follow-up period of 4.1 years, the primary outcome events occurred in 287 participants (29.7%). There was a significant interaction between proteinuria and sodium excretion for the primary outcome (P = 0.006). In patients with proteinuria of <0.5 g/d, sodium excretion was not associated with the primary outcome. However, in patients with proteinuria of ≥0.5 g/d, a 1.0 g/d increase in sodium excretion was associated with a 29% higher risk of adverse kidney outcomes. Moreover, in patients with proteinuria of ≥0.5 g/d, the hazard ratios (HRs) (95% confidence intervals[CIs]) for sodium excretion of <3.4 and ≥3.4 g/d were 2.32 (1.50-3.58) and 5.71 (3.58-9.11), respectively, compared with HRs for patients with proteinuria of <0.5 g/d and sodium excretion of <3.4 g/d. In sensitivity analysis with 2 averaged values of sodium and protein excretion at baseline and third year, the results were similar.

Conclusion

Higher urinary sodium excretion was more strongly associated with an increased risk of adverse kidney outcomes in patients with higher proteinuria levels.

Low dietary sodium potentially mediates COVID-19 prevention associated with whole-food plant-based diets

Compared with an omnivorous Western diet, plant-based diets containing mostly fruits, vegetables, grains, legumes, nuts and seeds, with restricted amounts of foods of animal origin, are associated with reduced risk and severity of COVID-19. Additionally, inflammatory immune responses and severe acute respiratory symptoms of COVID-19, including pulmonary oedema, shortness of breath, fever and nasopharyngeal infections, are associated with Na toxicity from excessive dietary Na. High dietary Na is also associated with increased risks of diseases and conditions that are co-morbid with COVID-19, including chronic kidney disease, hypertension, stroke, diabetes and obesity. This article presents evidence that low dietary Na potentially mediates the association of plant-based diets with COVID-19 prevention. Processed meats and poultry injected with sodium chloride contribute considerable amounts of dietary Na in the Western diet, and the avoidance or reduction of these and other processed foods in whole-food plant-based (WFPB) diets could help lower overall dietary Na intake. Moreover, high amounts of K in plant-based diets increase urinary Na excretion, and preagricultural diets high in plant-based foods were estimated to contain much lower ratios of dietary Na to K compared with modern diets. Further research should investigate low Na in WFPB diets for protection against COVID-19 and co-morbid conditions.

Effect of nutritional supplementation on mortality in peritoneal dialysis patients: A meta-analysis

BACKGROUND

Malnutrition is a common clinical problem in peritoneal dialysis (PD) patients and is a predictor of mortality. This work analyzes the effect of nutritional supplementation for PD patients on all-cause and cardiovascular disease (CVD)-related deaths by meta-analysis.

METHODS

A study about nutritional interventions for PD patients on all-cause or CVD-related mortality is included.

RESULTS

Eight studies were included. The results showed that nutritional intervention can reduce all-cause mortality in PD patients (HR, 0.71; 95% confidence interval (CI), 0.64-0.79; p < 0.01). In CVD-related mortality, the results also showed that nutritional interventions significantly reduce CVD-related mortality (HR, 0.75; 95% CI, 0.64-0.87; p < 0.01). In exploratory analysis, vitamin D, folic acid, and high-plant-protein ratio intake have relative advantages.

CONCLUSION

Appropriate nutritional supplementation to PD patients can effectively reduce all-cause and CVD- related mortality in clinical practice, especially for vitamin D, folic acid, sodium supplements, and a high proportion of plant protein.

Plant or Animal-Based or PLADO Diets: Which Should Chronic Kidney Disease Patients Choose?

Nutrition therapy is the cornerstone treatment for chronic kidney disease (CKD). Although much attention has been given to dietary protein intake in CKD patients, many findings now demonstrate that the type of dietary protein intake may be more critical for CKD patients. In protein bioavailability and malnutrition prevention, many physicians recommend that CKD patients adhere to a low protein diet and restrict their plant foods, such as vegetables, fruits, and soybeans. However, nephrologists should not ignore the potential benefits of plant foods for CKD patients. It is not advisable to restrict the intake of plant foods in the later stage of CKD simply to prevent the development of hyperkalemia and malnutrition. This article highlights the benefits and possible problems of a plant-dominant low protein diet (PLADO) diet, defined as an LPD with dietary protein intake of 0.6-0.8 g/kg/day with at least 50% plant-based source for CKD patients. We hope to provide new opinions for clinical work and CKD patients.