Dietary interventions for adults with chronic kidney disease

A practical approach to nutritional intervention for people with chronic kidney disease in Vietnam

BACKGROUND AND OBJECTIVES

A comprehensive nutritional management is necessary for favourable outcomes in patients with chronic kidney disease (CKD). We aimed to assess the changes in nutritional status and disease progression with nutritional management where renal replacement therapy (RRT) was not in place.

METHODS AND STUDY DESIGN

A quasi-experiment intervention was conducted on 70 CKD patients at stages 3-5 from July to December 2022. Participants were excluded if they underwent RRT, including dialy-sis (hemodialysis or peritoneal dialysis), or kidney transplantation. The nutritional regimen covered nutrition-al counseling, samples of the dietary menu, and supplement products. We evaluated nutritional status using Subjective Global Assessment (SGA) scale and sub-clinical blood test at T0 (hospital admission) and T1 (two weeks after the admission or 24 hours before the discharge).

RESULTS

After the intervention, the number of patients classified as malnutrition or at risk of malnourished reduced significantly (65.7% to 54.3% and 25.7% and 5.7%, respectively). The serum concentration of urea, creatinine and parathyroid hormone decreased remarkably, especially in patients receiving nutritional management. In the intervention group, the dietary pattern provided increased intakes of calcium and iron at T1, while phosphorus, sodium and potassium decreased after follow-up. Nausea/vomiting, loss of appetite, tiredness and sleep disorders were improved in the intervention compared to the control group.

CONCLUSIONS

Nutritional therapy enhanced the nutritional sta-tus, and quality of dietary and renal function in CKD patients without RRT. Applying nutrition education and treatment at an early stage can slow CKD progression, which should be applicable elsewhere in Vietnam.

Impact of dietary carbohydrate, fat or protein restriction on the human gut microbiome: a systematic review

Restriction of dietary carbohydrates, fat and/or protein is often used to reduce body weight and/or treat (metabolic) diseases. Since diet is a key modulator of the human gut microbiome, which plays an important role in health and disease, this review aims to provide an overview of current knowledge of the effects of macronutrient-restricted diets on gut microbial composition and metabolites. A structured search strategy was performed in several databases. After screening for inclusion and exclusion criteria, thirty-six articles could be included. Data are included in the results only when supported by at least three independent studies to enhance the reliability of our conclusions. Low-carbohydrate (<30 energy%) diets tended to induce a decrease in the relative abundance of several health-promoting bacteria, including Bifidobacterium, as well as a reduction in short-chain fatty acid (SCFA) levels in faeces. In contrast, low-fat diets (<30 energy%) increased alpha diversity, faecal SCFA levels and abundance of some beneficial bacteria, including Faecalibacterium prausnitzii. There were insufficient data to draw conclusions concerning the effects of low-protein (<10 energy%) diets on gut microbiota. Although the data of included studies unveil possible benefits of low-fat and potential drawbacks of low-carbohydrate diets for human gut microbiota, the diversity in study designs made it difficult to draw firm conclusions. Using a more uniform methodology in design, sample processing and sharing raw sequence data could foster our understanding of the effects of macronutrient restriction on gut microbiota composition and metabolic dynamics relevant to health. This systematic review was registered at https://www.crd.york.ac.uk/prospero as CRD42020156929.

Estimated 24-h urinary sodium excretion and risk of end-stage kidney disease

The association between sodium intake and long-term kidney disease endpoints is debated and yet to be proven. We aimed to investigate the associations of estimated 24-h urinary sodium excretion, reflecting daily sodium intake, with the incidence of end-stage kidney disease (ESKD). In this prospective cohort study including 444,375 UK Biobank participant, 865 (0.2%) ESKD events occurred after median follow-up of 12.7 years. For every 1 g increment in estimated 24-h urinary sodium excretion, multivariable-adjusted hazard ratio for incident ESKD was 1.09 (95% confidence interval 0.94-1.26). Nonlinear associations were not detected with restricted cubic splines. The null findings were confirmed by a series of sensitivity analyses, which attenuated potential bias from measurement errors of the exposure, regression dilution, reverse causality, and competing risks. In conclusion, there is insufficient evidence that estimated 24-h urinary sodium excretion is associated with the incidence of ESKD.

An investigation of low-protein diets' qualification rates and an analysis of their short-term effects for patients with CKD stages 3-5: a single-center retrospective cohort study from China

BACKGROUND

The feasibility and efficacy of low-protein diets (LPD) treatment in chronic kidney disease (CKD) is controversial. Based on the characteristics of the Chinese diet, we observe the qualification rates and short-term clinical effects of LPD for CKD patients in our center.

METHODS

This is a retrospective cohort study. CKD stages 3-5 patients who were regularly followed up 5 times (over 2 years) and treated with LPD were included. We collected clinical data to observe the changes in LPD qualification rates and divided patients into LPD and non-LPD group according to the average dietary protein intake (DPI) of 5 follow-up time points and compared the changes in primary and secondary outcome measures between the two groups.

RESULTS

We analyzed data from 161 eligible CKD stages 3-5 patients. From baseline to the 5th follow-up time point, the LPD qualification rates of all patients were 11.80%, 35.40%, 47.82%, 53.43% and 54.04%, respectively. For primary outcome measures, the urine protein/creatinine ratio (UPCR) decreased more in the LPD group than in the non-LPD group [Median (interquartile range, IQR) of the difference between the 5th follow-up time point and baseline: 0.19 (- 0.01-0.73) vs. 0.10 (- 0.08-0.27), P < 0.001]. We constructed three classes of mixed linear models (model I, II, III). The UPCR slopes were all negative in the LPD group and positive in the non-LPD group (P < 0.001). Meanwhile, in model I, the estimate glomerular filtration rate(eGFR) decline slope in the LPD group was lower than that in the non-LPD group [slope (standard error): - 1.32 (0.37) vs. - 2.35 (0.33), P = 0.036]. For secondary outcome measures, body mass index (BMI) triglycerides (TG), body weight, and fat free mass (FFM) showed stable statistical differences in the comparison of LPD and non-LPD groups, with greater declines in the former.

CONCLUSION

The results of this study suggest that LPD treatment can reduce UPCR in patients with CKD stages 3-5, and may also delay the decline in eGFR. Meanwhile, it also reduces BMI, TG, body weight, and FFM, thus the need to prevent malnutrition in clinical implementation.

Quality of Life of Hemodialysis Patients in Greece: Associations with Socio-Economic, Anthropometric and Nutritional Factors

Chronic kidney disease (CKD) is a serious public health problem that, in recent decades, has taken on significant dimensions with serious effects on the quality of life (QoL) of patients. The purpose of this cross-sectional study is to evaluate the QoL of a sample of hemodialysis patients in Greece and the possible correlations with socio-economic and anthropometric factors, as well as with adherence to the Mediterranean Diet (MD). During September-November 2019, one-hundred and five (n = 105) patients with end-stage CKD (63.4 ± 13.09 years of age) who were regularly monitored in five public and private hemodialysis units in the region of Attica, completed a demographic questionnaire, the MedDietScore questionnaire, and the KDQOL-SF questionnaire. Females presented worse QoL than males (p < 0.05), and older patients presented worse QoL than younger patients (p < 0.01). Patients of higher educational status presented better QoL scores than those of lower educational status (p < 0.01), while those with low financial status presented lower QoL scores than patients of middle and high financial status (p < 0.01). Obese patients had lower QoL scores than overweight patients (p < 0.05), and overweight males scored higher than normal weight males (p < 0.05). Age was negatively correlated to the total and most of the scales of QoL (p < 0.01). A majority of the patients (90.5%) showed a moderate adherence to MD, although "work status" was the only QoL scale that was correlated to MD. Age, educational status and financial status accounted for 28.1% of the variance in the KDQOL-SF total score. Hemodialysis patients need support in various levels, such as social, financial and educational, as well as nutritional counseling to adopt a balanced diet and maintain a healthy weight, in order to achieve a better quality of life.

Effect of Uncertainty in Illness and Fatigue on Health-Related Quality of Life of Patients on Dialysis: A Cross-Sectional Correlation Study

This study aimed to determine the effect of uncertainty in illness and fatigue on the health-related quality of life of patients on dialysis. A community-based cross-sectional study was conducted among patients on hemodialysis (n = 80) and peritoneal dialysis (n = 81) in Korea. Data were collated using self-reported structured questionnaires. Multiple regression analysis was used to identify those factors affecting the physical and mental health-related quality of life of patients. Patients on peritoneal dialysis reported higher levels of fatigue (p < 0.001). Factors affecting the physical health-related quality of life of patients on dialysis were fatigue (p < 0.001), employment (p = 0.001), and exercise (p = 0.016), thus explaining the observed variance of 37%. Factors affecting mental health-related quality of life were fatigue (p < 0.001), uncertainty (p = 0.004), educational level (p = 0.005), and smoking (p = 0.035). To improve the health-related quality of life of patients on dialysis, clinicians should assess their fatigue levels and plan multidisciplinary interventions to manage it. In addition, education level and employment status should be considered, and tailored interventions should be provided to acquire positive coping strategies and health promotion behaviors to counter disease uncertainty.

Hypercaloric Diet Promotes Metabolic Disorders and Impaired Kidney Function

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

Dietary Risk Factors and Eating Behaviors in Peripheral Arterial Disease (PAD)

Dietary risk factors play a fundamental role in the prevention and progression of atherosclerosis and PAD (Peripheral Arterial Disease). The impact of nutrition, however, defined as the process of taking in food and using it for growth, metabolism and repair, remains undefined with regard to PAD. This article describes the interplay between nutrition and the development/progression of PAD. We reviewed 688 articles, including key articles, narrative and systematic reviews, meta-analyses and clinical studies. We analyzed the interaction between nutrition and PAD predictors, and subsequently created four descriptive tables to summarize the relationship between PAD, dietary risk factors and outcomes. We comprehensively reviewed the role of well-studied diets (Mediterranean, vegetarian/vegan, low-carbohydrate ketogenic and intermittent fasting diet) and prevalent eating behaviors (emotional and binge eating, night eating and sleeping disorders, anorexia, bulimia, skipping meals, home cooking and fast/ultra-processed food consumption) on the traditional risk factors of PAD. Moreover, we analyzed the interplay between PAD and nutritional status, nutrients, dietary patterns and eating habits. Dietary patterns and eating disorders affect the development and progression of PAD, as well as its disabling complications including major adverse cardiovascular events (MACE) and major adverse limb events (MALE). Nutrition and dietary risk factor modification are important targets to reduce the risk of PAD as well as the subsequent development of MACE and MALE.

Low-protein diet is inversely related to the incidence of chronic kidney disease in middle-aged and older adults: results from a community-based prospective cohort study

PURPOSE

Dietary protein intake can modulate renal health. However, the effect of dietary protein restriction on kidney function in the general population remains unclear. This study aimed to examine the association between total protein intake and new-onset chronic kidney disease (CKD) in Korean adults.

METHODS

We included 7339 participants from the Korean Genome and Epidemiology Study. Participants were divided into low-protein diet (LPD, < 0.8 g/kg/day), normal-protein diet (NPD, 0.8-1.3 g/kg/day), and high-protein diet (HPD, > 1.3 g/kg/day) groups. New-onset CKD was defined as two consecutive events of estimated glomerular filtration rate < 60 mL/min/1.73 m². Multivariable Cox hazard regression analysis was conducted to examine the association of total protein intake with new-onset CKD. Subgroup analyses according to diabetes mellitus (DM) status were performed. We performed the same analyses by dividing participants into total protein, plant protein, and animal protein intake tertiles.

RESULTS

During a median follow-up of 13.7 years, 633 (8.7%) participants newly developed CKD. The fully adjusted hazard ratios (HR) with 95% confidence interval (CI) for incident CKD of the LPD and HPD groups compared with the NPD group were 1.49 (1.18-1.87) and 0.63 (0.45-0.87), respectively. The HR (95% CI) of the highest tertile group of plant protein intake for incident CKD was 0.72 (0.54-0.93), compared with that of the lowest tertile group. Similar trends were observed only in the non-DM subgroup, not in the DM subgroup.

CONCLUSION

Protein intake, especially plant proteins, was negatively associated with the incidence of new-onset CKD in middle-aged and older Korean adults.

Assessment of visceral adiposity index and lipid accumulation product index as markers of chronic kidney disease among diabetic and hypertensive patients at the Bamenda Regional Hospital, Cameroon: a cross-sectional study

Introduction

very limited studies have emphasized the importance of visceral adiposity index (VAI) and lipid accumulation product index (LAPI) in the prevention and management of chronic kidney disease (CKD) especially in diabetic and hypertension patients in developing countries including Cameroon. This study aimed at assessing whether VAI and LAPI are markers of CKD among diabetic and hypertensive patients at the Bamenda Regional Hospital, Cameroon.

Methods

this analytical cross-sectional study was conducted at Bamenda Regional Hospital and involved 200 diabetic and/or hypertensive patients, including 77 males and 123 females. The participant´s anthropometric indices, biochemical parameters, VAI, LAPI, and glomerular filtration rate were investigated. A structured questionnaire was used to assess some risk factors of CKD and participant lifestyle.

Results

the overweight (41%) and obesity (34%) statuses were prevalent in the population. A considerable proportion of subjects had elevated total cholesterol (46%), low-density lipoprotein (LDL) cholesterol (37.50%), triglycerides (24.5%), urea (40.5%) and creatinine (53.5%) levels. Stage 1 to 3 CKD was largely present in the elderly (>54-year-old) affecting the majority of patients (57.5%). Low education level and lack of physical activity were significantly associated with the prevalence of CKD (p < 0.001). On the contrary to creatinine (unadjusted OR = 1.36; 95% CI: 1.13-1.62), urea (unadjusted OR = 1.02; 95% CI: 1.01-1.03), HDL (unadjusted OR = 0.87; 95% CI: 0.78-0.97), total cholesterol/HDL ratio (unadjusted OR = 1.38; 95% CI; 1.12-1.71), VAI (unadjusted OR = 1.13; 95% CI: 1.05-1.22) and LAPI (unadjusted OR = 1.00; 95% CI: 1.00-1.00) were significantly associated with CKD status of the patients while HDL was negatively associated (unadjusted OR = 0.87; 95% CI: 0.78-0.97). The 9.905 and 5679 cut-offs of VAI and LAPI respectively for CKD discrimination obtained high sensitivity (75.0%) and specificity (≥79.6%).

Conclusion

visceral adiposity index and LAPI were associated with CKD among diabetic and hypertensive patients. Visceral adiposity index and LAPI could be user-friendly tools for the early diagnosis of CKD among these categories of patients in Cameroon.

Investigation of the Renal Protective Effect of Combined Dietary Polyphenols in Streptozotocin-Induced Diabetic Aged Rats

Natural polyphenols are widely reported to have a large range of pharmacological properties, especially antioxidant activities and free radical scavenging capacities. In this study, we investigate the effects of naringin, chlorogenic acid, and quercetin mixtures (NCQ) on renal fibrosis in streptozotocin (STZ)-induced diabetic aged rats and its underlying mechanisms for ten consecutive weeks. The oxidative defense system in the kidneys of treated rats was found to be improved. Several biomarkers were investigated including the blood urea nitrogen, creatinine, and uric acid. Moreover, antioxidant parameters were evaluated and we found that superoxide dismutase, catalase, glutathione peroxidase, Na⁺-K⁺-ATPase activities, the nitric oxide production, the protein carbonyl, the advanced oxidation protein products, lipid peroxidation, and reduced glutathione levels were all significantly balanced and close to control values. In addition, NCQ restored renal injuries and fibrosis as assessed by histological method and molecular biology investigation of the matrix metalloproteinase, the transforming growth factor-beta TGF-β, the tumor necrosis factor TNFα, and p53 expression. Our study proposes the NCQ combination as potential plant-derived bioactive compounds to prevent diabetic nephropathy.

The Effect of Dietary Intervention on Autosomal-Dominant Polycystic Kidney Disease (ADPKD) Patients on Tolvaptan and Their Quality of Life

Background and objective

Autosomal-dominant polycystic kidney disease (ADPKD) is the most common inherited renal disorder; it affects people of all ethnic groups and is found in up to 10% of patients with end-stage renal disease (ESRD). Dietary intervention is important in people with renal disease, and it has been linked to greater estimated glomerular filtration rate (eGFR) preservation. Tolvaptan, an orally-active nonpeptide, selective arginine vasopressin (AVP) V2R antagonist, was recently licensed in numerous countries for the treatment of ADPKD. The aim of this study was to assess the role of dietary intervention in decreasing the osmotic load on the urine volume and its impact on the quality of life (QOL) of patients with ADPKD on tolvaptan.

Methods

This prospective cohort study was carried out at a Hamilton nephrology genetics clinic. ADPKD patients on well-tolerated doses of tolvaptan for three months were included in the study. Gitelman and Bartter Symptom Health-related QOL questionnaire was used among the study participants.

Results

Our study consisted of nine adult patients with ADPKD who were on a stable dose of tolvaptan therapy. Patients had laboratory values for urine volume, sodium (Na), and urea. No significant difference was found between pre- and post-diet intervention values in 24-hour urine volume (5.9 vs. 5.49 L/d; p=0.423), urine Na (p=0.174), and 24-hour urine urea (p=0.404).

Conclusion

Dietary intervention in ADPKD patients on tolvaptan therapy can play a vital role in improving their QOL. Further research including interventional studies and clinical trials with larger sample sizes is needed to gain deeper insight into the subject.

The Association Between Total Protein Intake and All-Cause Mortality in Middle Aged and Older Korean Adults With Chronic Kidney Disease

Background and Aims

Over the past decades, the optimum protein intake for patients with chronic kidney disease (CKD) has been an important, controversial issue. Dietary protein restriction has been commonly recommended for patients with CKD for preserving kidney function. However, evidence of the associations between long-term protein intake and mortality is not consistent in patients with CKD. Therefore, we aimed to examine the associations between total protein intake and all-cause mortality in Korean adults with CKD.

Methods

From three sub-cohorts of the Korean Genome and Epidemiology Study (KoGES) starting from 2001, total 3,892 participants with eGFR < 60 mL/min/1.73 m² (CKD stage 3–5) were included in this study. Dietary data were collected using food-frequency questionnaires at baseline. Deaths were followed from 2001 to 2019. Cox proportional hazards regression model was used to evaluate the association between protein intake and all-cause mortality.

Results

During a median follow-up (min-max) of 11.1 years (0.3–15.1), 602 deaths due to all causes of mortality were documented. After adjustment for covariates, higher total protein intake was not associated with all-cause mortality [highest vs. lowest quintile of total protein intake (g/kg/day) and proportion (%) (Q5 vs. Q1), HR = 1.14 (0.75–1.72), and HR = 0.87 (0.67–1.13)] in CKD stage 3–5 patients.

Conclusion

Dietary protein intake was not associated with mortality from all causes in patients with CKD. Further research is needed to establish optimal protein intake levels and examine the impact of the dietary source of protein on various health outcomes and mortality in CKD.

Polyphenols and Their Metabolites in Renal Diseases: An Overview

Kidney diseases constitute a worldwide public health problem, contributing to morbidity and mortality. The present study aimed to provide an overview of the published data regarding the potential beneficial effects of polyphenols on major kidney diseases, namely acute kidney injury, chronic kidney disease, diabetic nephropathy, renal cancer, and drug-induced nephrotoxicity. This study consists of a bibliographical review including in vitro and in vivo studies dealing with the effects of individual compounds. An analysis of the polyphenol metabolome in human urine was also conducted to estimate those compounds that are most likely to be responsible for the kidney protective effects of polyphenols. The biological effects of polyphenols can be highly attributed to the modulation of specific signaling cascades including those involved in oxidative stress responses, anti-inflammation processes, and apoptosis. There is increasing evidence that polyphenols afford great potential in renal disease protection. However, this evidence (especially when in vitro studies are involved) should be considered with caution before its clinical translation, particularly due to the unfavorable pharmacokinetics and extensive metabolization that polyphenols undergo in the human body. Future research should consider polyphenols and their metabolites that indeed reach kidney tissues.

Diet-Related Inflammation is Associated with Malnutrition-Inflammation Markers in Maintenance Hemodialysis Patients: Results of a Cross-Sectional Study in China Using Dietary Inflammatory Index

Purpose

This cross-sectional study aimed to explore the association between the inflammation potential of the diet and malnutrition-inflammation status in Chinese maintenance hemodialysis (MHD) patients.

Methods

Dietary Inflammatory Index (DII) was computed based on a semi-quantitative food frequency questionnaire. Malnutrition-inflammation status was assessed by six indexes, including C-reactive protein (CRP), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), hemoglobin (HB), albumin (ALB) and malnutrition-inflammation score (MIS). Multivariable linear regression and logistic regression were employed adjusting for covariables including age, gender, body mass index and dialysis vintage.

Results

A total of 161 Chinese MHD patients with an average age of 60.0 ± 13.6 years were enrolled. The median (IQR) DII score among participants was 0.60 (−0.80, 2.32), revealing a generally pro-inflammatory diet. DII was positively associated with MIS score (β= 0.61, 95% CI: 0.51, 0.69, p < 0.0001) and CRP (β = 0.54, 95% CI: 0.46, 0.63, p < 0.0001). A negative relationship between DII and NLR (β = −0.37, 95% CI: −0.61, −0.13, p = 0.008) was found in the most anti-inflammatory diet. Multivariable logistic regression showed that each unit increase in DII was linked with 3.06 (95% CI: 1.39, 6.69, p = 0.005) times increased odds of MIS.

Conclusion

Diet with a higher DII score may act as a potential trigger contributing to the development of malnutrition-inflammation status. Further studies for verification and for developing strategies to decrease the dietary inflammation burden are warranted.

Relationship between modifiable lifestyle factors and chronic kidney disease: a bibliometric analysis of top-cited publications from 2011 to 2020

BACKGROUND

Chronic kidney disease (CKD) affects 8 to 16% of the world's population and is one of the top ten important drivers of increasing disease burden. Apart from genetic predisposition, lifestyle factors greatly contribute to the incidence and progression of CKD. The current bibliometric analysis aims to characterize the current focus and emerging trends of the research about the impact of modifiable lifestyle factors on CKD.

METHODS

We searched articles addressing the impact of modifiable lifestyle factors on the incidence and/or progression of CKD, published between 2011 and 2020, from the Science Citation Index Expanded (SCIE) database. An adjusted citation index, which considered both the original citation count and publication year, was derived for the selection of most-cited publications. Publishing trends, co-authorship network, keywords, and research hotspots were analyzed and visualized.

RESULTS

Among the top 100 most influential articles, 32 were narrative reviews, 16 systematic reviews and/or meta-analysis, 44 clinical research, and 8 basic research. The United States occupied a dominant position in the perspective of article numbers and international partnerships, followed by European countries. The modifiable factors that drew the most and constant attention over the decade were diet or nutrition management reported in 63 papers, followed by obesity or body mass index (n = 27), and physical activity or exercises (n = 8). Alcohol consumption, fish oil, chain fatty-acids, and water-soluble vitamins were emerging hotspots identified in the recent most cited publications.

CONCLUSIONS

Based on the bibliometric analysis of the most influential articles, our study provides a comprehensive description of publishing trends and research focus over a decade in the field of lifestyle factors' impact on CKD. Diet, obesity, and physical activity were factors receiving the most attention in this topic.

Food Literacy and Its Associated Factors in Non-Dialysis Patients with Chronic Kidney Disease in China: A Cross-Sectional Study

PURPOSE

Nephrology professionals' understanding of food literacy (FL) and influencing factors is significant for nutrition management, which is key to controlling disease progress among non-dialysis patients with chronic kidney disease (CKD). However, few studies have explored FL in CKD patients. Hence, this study aimed to investigate the level of FL of non-dialysis patients with CKD and to analyze influencing factors in China.

PATIENTS AND METHODS

A total of 203 CKD patients without dialysis were recruited from August to December 2020 to participate in a cross-sectional study. Food literacy was assessed by a modified short food literacy questionnaire for adults. Related influencing factors were measured by the motivation for dietary self-control scale and the satisfaction with dietary behavior scale. Data were also collected regarding patients' health information-seeking behavior (four items), satisfaction and compliance with dietary advice from healthcare professionals (two items), and demographics and clinical diagnoses.

RESULTS

The mean age of patients was 44.5 years (range 18 to 75), and 42.5% were male. Most (50.2%) were in stages 1-2 of CKD. The mean FL score of these patients was 38.75±0.38. The multivariable linear regression analysis shows that secondary educational level (β=0.221, p=0.004), motivation for controlling diet (β=0.198, p=0.003), satisfaction with dietary behaviors (β=0.319, p<0.001), and health information-seeking behavior (β=0.146, p=0.019) were significant influencing factors.

CONCLUSION

Food literacy of Chinese CKD patients without dialysis should be improved. Patients with higher education levels exhibit more active information-seeking behaviors, have greater satisfaction with dietary behaviors, and their motivation for dietary self-control is more likely to be associated with better FL. Healthcare workers should be aware of factors influencing FL and attempt to integrate assessment of FL into routine food-related education for CKD patients.

Assessment and management of obesity and metabolic syndrome in children with CKD stages 2-5 on dialysis and after kidney transplantation-clinical practice recommendations from the Pediatric Renal Nutrition Taskforce

Obesity and metabolic syndrome (O&MS) due to the worldwide obesity epidemic affects children at all stages of chronic kidney disease (CKD) including dialysis and after kidney transplantation. The presence of O&MS in the pediatric CKD population may augment the already increased cardiovascular risk and contribute to the loss of kidney function. The Pediatric Renal Nutrition Taskforce (PRNT) is an international team of pediatric renal dietitians and pediatric nephrologists who develop clinical practice recommendations (CPRs) for the nutritional management of children with kidney diseases. We present CPRs for the assessment and management of O&MS in children with CKD stages 2-5, on dialysis and after kidney transplantation. We address the risk factors and diagnostic criteria for O&MS and discuss their management focusing on non-pharmacological treatment management, including diet, physical activity, and behavior modification in the context of age and CKD stage. The statements have been graded using the American Academy of Pediatrics grading matrix. Statements with a low grade or those that are opinion-based must be carefully considered and adapted to individual patient needs based on the clinical judgment of the treating physician and dietitian. Research recommendations are provided. The CPRs will be periodically audited and updated by the PRNT.

Intradialytic nutrition and quality of life in Chilean older patients in hemodialysis with protein-energy wasting

PURPOSE

The study assessed the impact of intradialytic oral nutritional supplementation on the quality of life in patients receiving hemodialysis and diagnosed with protein energy wasting.

METHODS

A pre-test post-test quasi-experimental study was conducted before and after 3 months of intradialytic oral nutritional supplementation on 109 older hemodialysis patients. We measured before and after 3 months of intradialytic oral nutritional supplementation, the quality of life score, the burden of kidney disease, three quality of life scales and the mental and physical health status using KDQoL-SF™ 1.3, body composition and biochemical parameters of nutritional condition.

RESULTS

The mean age of the patients was 69.4 ± 3.4 years, 59% were male, and the time on dialysis was 63.5 ± 52.6 months. Comparing the baseline with month 3 of intradialytic oral nutritional supplementation, we observed to better quality of life. In contrast to malnutrition, score, specifically increased significantly score of symptoms/problems list related to hemodialysis, sexual function, social and cognitive function, sleep, pain, energy/fatigue and general state of health. Significant changes were also found in nutritional status, energy intake and body composition indicators. After 3 months of intradialytic oral nutritional supplementation, we observed a nutritional status recovery in one or more indicators in 92% of the patients.

CONCLUSION

Our findings indicate that 3 months of intradialysis oral nutritional supplementation improves the components of physical and mental quality of life and nutritional status in older patients receiving hemodialysis diagnosed with loss of protein energy. These results are relevant to improve the experience of patients with protein energy loss receiving hemodialysis.

Development and Relative Validity of the Chronic Kidney Disease Short Food Frequency Questionnaire (CKD SFFQ) to Determine Diet Quality and Dietary Habits among Adults with Chronic Kidney Disease

Limited instruments are available to determine diet quality among US adults with chronic kidney disease (CKD). The purpose of this study was two-fold: (1) to develop a food frequency questionnaire, CKD SFFQ, for adults with CKD and (2) to validate the CKD SFFQ against two 24-h recalls in determining diet quality (DQ). A 57-item CKD SFFQ was developed through a content validation method. Adults with CKD (n = 46) completed the CKD SFFQ and 2-24-h recalls. Statistical analyses included descriptive statistics, frequencies, t-tests, Pearson correlations, and Bland-Altman plots. All data were analyzed using JMP SAS v15 with statistical significance detected at p < 0.05. Results showed no differences for the overall DQ (p = 0.11) and the nine whole-food components (p = 0.07 to p = 0.44) when comparing the CKD SFFQ to the 2-24-h recalls. Pearson correlation coefficients ranged from -0.39 (refined grains) to 0.60 (greens and beans). Bland-Altman plots showed overall good agreement and there was a systematic trend towards higher estimates with the CKD SFFQ, particularly for overall DQ, total proteins, and dairy. The majority of participants rarely or never consumed grains, fruits, vegetables, seafood, and plant proteins. The CKD SFFQ was demonstrated to be an acceptable method to determine DQ for adults with CKD.

Serum phosphate and chronic kidney and cardiovascular disease: Phosphorus potential implications in general population

It has already been established that in end-stage renal disease, hyperphosphatemia causes soft tissue calcification including vascular calcifications. It has also been supported that there is a connection between increased serum phosphate and morbidity in subjects, who suffer from renal disease. However, studies in these populations conferred mixed results. Several warnings are included in the role of serum phosphorus on cardiovascular disease in normal populations. Homeostasis of serum phosphate is obtained by the cooperation between regulatory hormones, cellular receptors and bone metabolic factors. There is the probability that one or more phosphate regulatory factors, rather than phosphate directly, may be responsible for observed associations with calcification and cardiovascular events in normal populations. Experimental studies have shown that the restriction of dietary phosphate prevents the progression of kidney dysfunction, although high dietary phosphate aggravates the renal function. In the current review, we discuss the role of serum phosphorus on progression of renal dysfunction and cardiovascular outcomes in chronic kidney disease patients and its involvement in important health risks in the general population.

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

BACKGROUND/OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

[Frailty in renal diseases]

Frailty beschreibt einen Zustand reduzierter Belastbarkeit gegenüber Stressfaktoren, welcher u. a. Folge altersbedingter Abbauprozesse verschiedener Organsysteme ist und mit einem erhöhten Risiko für Stürze, Hospitalisationen, funktionelle Einschränkung und Mortalität assoziiert ist. Frailty tritt bei Patienten mit CKD früher und häufiger auf als in der Allgemeinbevölkerung und ist ein wichtiger und potenziell modifizierbarer Risikofaktor für eine erhöhte Sterblichkeit und Hospitalisationsrate sowie eine reduzierte Lebensqualität. Die Erkennung von Frailty bei Patienten mit CKD ermöglicht eine Identifikation von wichtigen und potenziell modifizierbaren Risikofaktoren.

Eine frühzeitige nephrologische Beurteilung sowie eine interdisziplinäre Zusammenarbeit mit Geriatern, Allgemeinmedizinern, Physiotherapeuten, Ergotherapeuten und Ernährungsberatung sind essenzielle Bausteine in der Prävention und Therapie von Frailty.

Zur Messung von Frailty existieren verschiedene Instrumente, wobei keines in der Erkennung von Frailty bei CKD-Patienten als überlegen identifiziert wurde. Die Auswahl des Screeninginstruments sollte daher unter Berücksichtigung der klinischen Rahmenbedingungen und der verfügbaren Ressourcen erfolgen. In diesem Artikel wird eine Strategie zur frühen Identifikation von gebrechlichen Patienten mit CKD vorgeschlagen, welche auf einer multidiemensionalen und interdisziplinären Einschätzung beruht. Wichtiger als die Methode ist jedoch die Notwendigkeit, Patienten mit Frailty zu identifizieren.

Dietary Restriction for Kidney Protection: Decline in Nephroprotective Mechanisms During Aging

Dietary restriction (DR) is believed to be one of the most promising approaches to extend life span of different animal species and to delay deleterious age-related physiological alterations and diseases. Among others, DR was shown to ameliorate acute kidney injury (AKI) and chronic kidney disease (CKD). However, to date, a comprehensive analysis of the mechanisms of the protective effect of DR specifically in kidney pathologies has not been carried out. The protective properties of DR are mediated by a range of signaling pathways associated with adaptation to reduced nutrient intake. The adaptation is accompanied by a number of metabolic changes, such as autophagy activation, metabolic shifts toward lipid utilization and ketone bodies production, improvement of mitochondria functioning, and decreased oxidative stress. However, some studies indicated that with age, the gain of DR-mediated positive remodeling gradually decreases. This may be an obstacle if we seek to translate the DR approach into a clinic for the treatment of kidney diseases as most patients with AKI and CKD are elderly. It is well known that aging is accompanied by impairments in a huge variety of organs and systems, such as hormonal regulation, stress sensing, autophagy and proteasomal activity, gene expression, and epigenome profile, increased damage to macromolecules and organelles including mitochondria. All these age-associated changes might be the reasons for the reduced protective potential of the DR during aging. We summarized the available mechanisms of DR-mediated nephroprotection and described ways to improve the effectiveness of this approach for an aged kidney.

Optimizing Diet to Slow CKD Progression

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

A Mediterranean lifestyle is associated with favourable cardiometabolic markers in people with non-dialysis dependent chronic kidney disease

Adherence to a Mediterranean lifestyle may be a useful primary and secondary prevention strategy for chronic kidney disease (CKD). This cross-sectional study aimed to explore adherence to a Mediterranean lifestyle and its association with cardiometabolic markers and kidney function in 99 people aged 73⋅2 ± 10⋅5 years with non-dialysis dependant CKD (stages 3-5) at a single Australian centre. Adherence was assessed using an a priori index, the Mediterranean Lifestyle (MEDLIFE) index. Cardiometabolic markers (total cholesterol, LDL-cholesterol, HbA1c and random blood glucose) and kidney function (estimated GFR) were sourced from medical records and blood pressure measured upon recruitment. Overall, adherence to a Mediterranean lifestyle was moderate to low with an average MEDLIFE index score of 11⋅33 ± 3⋅31. Adherence to a Mediterranean lifestyle was associated with employment (r 0⋅30, P = 0⋅004). Mediterranean dietary habits were associated with cardiometabolic markers, such as limiting sugar in beverages was associated with lower diastolic blood pressure (r 0⋅32, P = 0⋅002), eating in moderation with favourable random blood glucose (r 0⋅21, P = 0⋅043), having more than two snack foods per week with HbA1c (r 0⋅29, P = 0⋅037) and LDL-cholesterol (r 0⋅41, P = 0⋅002). Interestingly, eating in company was associated with a lower frequency of depression (χ ² 5⋅975, P = 0⋅015). To conclude, Mediterranean dietary habits were favourably associated with cardiometabolic markers and management of some comorbidities in this group of people with non-dialysis dependent CKD.

Adequate Management of Phosphorus in Patients Undergoing Hemodialysis Using a Dietary Smartphone App: Prospective Pilot Study

Background

The renal diet is complex and requires alterations of the diet and careful monitoring of various nutrients. Elevated serum phosphorus is common among patients undergoing hemodialysis, and it is associated with many complications. Smartphone technology could be used to support both dietitians and patients by providing a source of accessible and reliable information.

Objective

The aim of this pilot is to assess the potential efficacy of an intervention using the educational and self-monitoring mobile app KELA.AE on the phosphorous management in hemodialysis patients. Results will be used to improve both the app and a planned, rigorous large-scale trial intended to assess app efficacy.

Methods

This is a prospective pilot study performed at the hemodialysis unit of Al Qassimi Hospital (Emirate of Sharjah, United Arab Emirates). All patients were assessed for eligibility and, based on inclusion criteria, considered for enrollment. Participants met with a dietitian once a week and used the mobile app regularly for 2 weeks. Outcomes (knowledge, self-reported nonadherence, dietary intake, anthropometry, and biochemical data) were measured. This pilot is reported as per guidelines for nonrandomized pilot and feasibility studies and in line with the CONSORT (Consolidated Standards of Reporting Trials) 2010 checklist for reporting pilot or feasibility trials.

Results

Of 26 subjects, 23 successfully completed the pilot. Patient dietary knowledge about phosphorous management improved from 51.4% (SD 13.9) to 68.1% (SD 13.3) after intervention with a large effect size (d=1.22, 95% CI 0.59 to 1.85). Dietary protein intake increased from a mean of 0.9 g/kg (SD 0.3) per day to a mean of 1.3 g/kg (SD 0.5) per day with a large effect size (d=1.07, 95% CI 0.45 to 1.69). Phosphorus to protein ratio dropped from a mean of 18.4 mg/g protein to 13.5 mg/g protein with a large effect size (d=0.83, 95% CI 0.22 to 1.43). There was no evidence of change in phosphorous intake, self-reported nonadherence, and serum phosphorus.

Conclusions

The findings of this prospective pilot reveal the potential efficacy of a smartphone app as a supportive nutrition education tool for phosphorus management in patients undergoing hemodialysis. This pilot study showed that the KELA.AE app has the potential to improve knowledge and dietary choices. A rigorous randomized controlled trial should be performed to evaluate the efficacy, assessing app use of a long-term intervention.

Nutrition in Chronic Kidney Disease-The Role of Proteins and Specific Diets

Chronic kidney disease (CKD) is a global public health burden, needing comprehensive management for preventing and delaying the progression to advanced CKD. The role of nutritional therapy as a strategy to slow CKD progression and uremia has been recommended for more than a century. Although a consistent body of evidence suggest a benefit of protein restriction therapy, patients' adherence and compliance have to be considered when prescribing nutritional therapy in advanced CKD patients. Therefore, these prescriptions need to be individualized since some patients may prefer to enjoy their food without restriction, despite knowing the potential importance of dietary therapy in reducing uremic manifestations, maintaining protein-energy status.

Dietary interventions with dietitian involvement in adults with chronic kidney disease: A systematic review

BACKGROUND

A comprehensive evidence base is needed to support recommendations for the dietetic management of adults with chronic kidney disease (CKD). The present study aimed to determine the effect of dietary interventions with dietitian involvement on nutritional status, well-being, kidney risk factors and clinical outcomes in adults with CKD.

METHODS

Cochrane Central Register of Controlled Trials, CINAHL, MEDLINE, PsycINFO and EMBASE.com were searched from January 2000 to November 2019. Intentional weight loss and single nutrient studies were excluded. Risk of bias was assessed using the Cochrane risk-of-bias tool. Effectiveness was summarised using the mean difference between groups for each outcome per study.

RESULTS

Twelve controlled trials (1906 participants) were included. High fruit and vegetable intake, as well as a multidisciplinary hospital and community care programme, slowed the decline in glomerular filtration rate in adults with stage 3-4 CKD. Interventions addressing nutrition-related barriers increased protein and energy intake in haemodialysis patients. A Mediterranean diet and a diet with high n-3 polyunsaturated fatty acids improved the lipid profile in kidney transplant recipients.

CONCLUSIONS

A limited number of studies suggest benefits as a result of dietary interventions that are delivered by dietitians and focus on diet quality. We did not identify any studies that focussed on our primary outcome of nutritional status or studies that examined the timing or frequency of the nutritional assessment. This review emphasises the need for a wider body of high-quality evidence to support recommendations on what and how dietetic interventions are delivered by dietitians for adults with CKD.

AGREEing on Nutritional Management of Patients with CKD-A Quality Appraisal of the Available Guidelines

Chronic kidney disease (CKD) is an important public health issue with increasing prevalence worldwide. Several clinical practice guidelines have been recently published regarding the nutritional management of CKD patients. The purpose of the present study is to evaluate the quality of the published guidelines and provide recommendation for future updates. PubMed, Scopus and Google Scholar were searched for relevant guidelines and 11 clinical practice guidelines were finally included. Guidelines developed by the American Society for Parenteral and Enteral nutrition (ASPEN), the Dietitians Association of Australia (DAA), the German Society for Nutritional Medicine (DGEM), the European Best Practice Guidelines (EBPG), the European Dialysis and Transplantation Nurses Association-European Renal Care Association (EDTNA-ERCA), the European Society for Clinical Nutrition and Metabolism (ESPEN), the Andalusian Group for Nutrition Reflection and Investigation (GARIN) group, the National Kidney foundation-Kidney Disease Outcomes Quality Initiative (KDOQI), the Italian Society of Nephrology-Association of Dieticians-Italian Association of Hemodialysis, Dialysis and Transplant (SIN-ANDID-ANED), and the Renal Association were assessed using the Appraisal of Guidelines for Research and Evaluation (AGREE) II tool. Guidelines by KDOQI, ESPEN, and DAA were of moderate quality and the rest of them were low-quality guidelines. Our study demonstrates gaps related to the development of guidelines and therefore greater emphasis on methodological approaches is recommended. AGREE II tool can be useful to improve quality of guidelines.

Adherence to Healthy Dietary Patterns and Risk of CKD Progression and All-Cause Mortality: Findings From the CRIC (Chronic Renal Insufficiency Cohort) Study

RATIONALE & OBJECTIVE

Current dietary guidelines recommend that patients with chronic kidney disease (CKD) restrict individual nutrients, such as sodium, potassium, phosphorus, and protein. This approach can be difficult for patients to implement and ignores important nutrient interactions. Dietary patterns are an alternative method to intervene on diet. Our objective was to define the associations of 4 healthy dietary patterns with risk for CKD progression and all-cause mortality among people with CKD.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

2,403 participants aged 21 to 74 years with estimated glomerular filtration rates of 20 to 70mL/min/1.73m2 and dietary data in the Chronic Renal Insufficiency Cohort (CRIC) Study.

EXPOSURES

Healthy Eating Index-2015, Alternative Healthy Eating Index-2010, alternate Mediterranean diet (aMed), and Dietary Approaches to Stop Hypertension (DASH) diet scores were calculated from food frequency questionnaires.

OUTCOMES

(1) CKD progression defined as≥50% estimated glomerular filtration rate decline, kidney transplantation, or dialysis and (2) all-cause mortality.

ANALYTICAL APPROACH

Cox proportional hazards regression models adjusted for demographic, lifestyle, and clinical covariates to estimate hazard ratios (HRs) and 95% CIs.

RESULTS

There were 855 cases of CKD progression and 773 deaths during a maximum of 14 years. Compared with participants with the lowest adherence, the most highly adherent tertile of Alternative Healthy Eating Index-2010, aMed, and DASH had lower adjusted risk for CKD progression, with the strongest results for aMed (HR, 0.75; 95% CI, 0.62-0.90). Compared with participants with the lowest adherence, the highest adherence tertiles for all scores had lower adjusted risk for all-cause mortality for each index (24%-31% lower risk).

LIMITATIONS

Self-reported dietary intake.

CONCLUSIONS

Greater adherence to several healthy dietary patterns is associated with lower risk for CKD progression and all-cause mortality among people with CKD. Guidance to adopt healthy dietary patterns can be considered as a strategy for managing CKD.

High salt aggravates renal inflammation via promoting pro-inflammatory macrophage in 5/6-nephrectomized rat

The increasing incident of chronic kidney disease (CKD) in recent years might be related to a change in dietary habits, known as excessive salt intake. Given excessive salt promotes pathogenic T cells responses. Since the importance of macrophage in the development of CKD, we addressed the effect of high salt loading on in a rat CKD model. We observed that 5/6Nx rats receiving a high salt diet showed strongly enhanced macrophage infiltration and activation in the renal tissue accompanied by deteriorated renal inflammation. Then we used the microarray expression profiling to detect the effect of additional Nacl on peritoneal macrophage derived from 5/6Nx. The NaCl treatment of macrophage extracted from 5/6Nx rat elicited a strong pro-inflammatory phenotype characterized by enhanced proinflammatory cytokine production, increased expression of molecules mainly involved in immune response process. This NaCl-induced pro-inflammatory macrophage phenotype was accompanied by increased phosphorylation of STAT1. Taken together, our study demonstrated that high salt intake promotes immune activation of macrophages through the STAT1 independently and exacerbates the kidney accompanied by promotion of inflammation. Thus, changes in diet may provide a novel strategy for the prevention or amelioration of CKD.

Health-related quality of life in patients with chronic kidney disease

Introduction: In the last three decades, health systems have continued to pay increasing attention to the quality of life (QOL) due to definitional changes in the concept of health and disease. The health-related quality of life (HRQOL) in patients with chronic kidney disease (CKD) is significantly affected, regardless of the stage of CKD. Areas covered: We attempt to thoroughly explore how CKD affects HRQOL domains with a quick primer on HRQOL assessment instruments in patients with CKD. Also, we pointed out the factors affecting HRQOL in patients with CKD as well as the clinical application of HRQOL in CKD management. Expert opinion: The general population enjoys higher HRQOL than patients with CKD in all domains. Similarly, pre-dialysis and kidney-transplant patients have better HRQOL than dialysis population. There are many factors which negatively impact HRQOL in CKD which include for example depression, anxiety, and cognitive impairment for the social domain, inactivity, and frailty for the physical domain as well as lack of social support and extroversion in the social domain. Additionally, social disparities and CKD-related factors would influence HRQOL. Of note, there is no global standard HRQOL assessment tool. Finally, HRQOL should be included in future CKD management guidelines.

'A sword of Damocles': patient and caregiver beliefs, attitudes and perspectives on presymptomatic testing for autosomal dominant polycystic kidney disease: a focus group study

BACKGROUND AND OBJECTIVES

Presymptomatic testing is available for early diagnosis of hereditary autosomal dominant polycystic kidney disease (ADPKD). However, the complex ethical and psychosocial implications can make decision-making challenging and require an understanding of patients' values, goals and priorities. This study aims to describe patient and caregiver beliefs and expectations regarding presymptomatic testing for ADPKD.

DESIGN, SETTING AND PARTICIPANTS

154 participants (120 patients and 34 caregivers) aged 18 years and over from eight centres in Australia, France and Korea participated in 17 focus groups. Transcripts were analysed thematically.

RESULTS

We identified five themes: avoiding financial disadvantage (insecurity in the inability to obtain life insurance, limited work opportunities, financial burden); futility in uncertainty (erratic and diverse manifestations of disease limiting utility, taking preventive actions in vain, daunted by perplexity of results, unaware of risk of inheriting ADPKD); lacking autonomy and support in decisions (overwhelmed by ambiguous information, medicalising family planning, family pressures); seizing control of well-being (gaining confidence in early detection, allowing preparation for the future, reassurance in family resilience); and anticipating impact on quality of life (reassured by lack of symptoms, judging value of life with ADPKD).

CONCLUSIONS

For patients with ADPKD, presymptomatic testing provides an opportunity to take ownership of their health through family planning and preventive measures. However, these decisions can be wrought with tensions and uncertainty about prognostic implications, and the psychosocial and financial burden of testing. Healthcare professionals should focus on genetic counselling, mental health and providing education to patients' families to support informed decision-making. Policymakers should consider the cost burden and risk of discrimination when informing government policies. Finally, patients are recommended to focus on self-care from an early age.

Body mass index change and estimated glomerular filtration rate decline in a middle-aged population: health check-based cohort in Japan

BACKGROUND

Obesity is a growing public health problem worldwide. We evaluated the mediators and association between changes in obesity metrics and renal outcomes in the general population.

METHODS

Using the Japanese nationwide health check-based cohort from April 2011 to March 2019, we selected individuals aged 40-74 years, with a baseline estimated glomerular filtration rate (eGFR) ≥45 mL/min/1.73 m², whose body mass index (BMI) change was assessed. The primary outcome was combined 30% decline in eGFR, eGFR <15 mL/min/1.73 m² and end-stage renal disease.

RESULTS

During 245 147 person-years' follow-up among 50 604 participants (mean eGFR, 83.7 mL/min/1.73 m²; mean BMI, 24.1 kg/m²), 645 demonstrated eGFR decline (incidence rate 2.6/1000 person-years, 95% CI: 2.4 to 2.8). We observed continued initial changes in BMI for over 6 years and a U-shaped association between BMI change and eGFR decline. Compared with 0% change in BMI, adjusted HRs for changes of -10%, -4%, 4% and 10% were 1.53 (95% CI: 1.15 to 2.04), 1.14 (95% CI: 1.01 to 1.30), 1.16 (95% CI: 1.02 to 1.32) and 1.87 (95% CI: 1.25 to 2.80), respectively. The percentage of excess risk of BMI increase (>4%) mediated by three risk factors (blood pressure, haemoglobin A1c and total cholesterol), was 13.3%.

CONCLUSION

In the middle-aged Japanese population, both, increase and decrease in BMI were associated with subsequent eGFR decline. Changes in risk factors mediated a small proportion of the association between BMI increase and eGFR decline. Our findings support the clinical significance of monitoring BMI as a renal risk factor.

Perceptions on Adherence to Dietary Prescriptions for Adults with Chronic Kidney Disease on Hemodialysis: A Qualitative Study

Diet is one of the modifiable lifestyle factors in management of kidney disease. We explored perceptions on adherence to dietary prescriptions for adults with chronic kidney disease on hemodialysis. This was a qualitative descriptive study. Participants were purposively selected at renal clinics/dialysis units at national referral hospitals in Kenya. Data were collected using in-depth interviews, note-taking and voice-recording. The data were managed and analyzed thematically in NVIV0-12 computer software. Study participants were 52 patients and 40 family caregivers (42 males and 50 females) aged 20 to 69 years. Six sub-themes emerged in this study: “perceived health benefits”; “ease in implementing prescribed diets”; “cost of prescribed renal diets”; “nutrition information and messages”; “transition to new diets” and “fear of complications/severity of disease”. Both patients and caregivers acknowledged the health benefits of adherence to diet prescriptions. However, there are mixed messages to the patients and caregivers who have challenges with management and acceptability of the prescriptions. Most of them make un-informed dietary decisions that lead to consumption of unhealthy foods with negative outcomes such as metabolic waste accumulation in the patients’ bodies negating the effects of dialysis and undermining the efforts of healthcare system in management of patients with chronic kidney disease.

Impact of Dietary Potassium Restrictions in CKD on Clinical Outcomes: Benefits of a Plant-Based Diet

In patients with advanced-stage chronic kidney disease (CKD), progressive kidney function decline leads to increased risk for hyperkalemia (serum potassium > 5.0 or >5.5 mEq/L). Medications such as renin-angiotensin-aldosterone system inhibitors pose an additional hyperkalemia risk, especially in patients with CKD. When hyperkalemia develops, clinicians often recommend a diet that is lower in potassium content. This review discusses the barriers to adherence to a low-potassium diet and the impact of dietary restrictions on adverse clinical outcomes. Accumulating evidence indicates that a diet that incorporates potassium-rich foods has multiple health benefits, which may also be attributable to the other vitamin, mineral, and fiber content of potassium-rich foods. These benefits include blood pressure reductions and reduced risks for cardiovascular disease and stroke. High-potassium foods may also prevent CKD progression and reduce mortality risk in patients with CKD. Adjunctive treatment with the newer potassium-binding agents, patiromer and sodium zirconium cyclosilicate, may allow for optimal renin-angiotensin-aldosterone system inhibitor therapy in patients with CKD and hyperkalemia, potentially making it possible for patients with CKD and hyperkalemia to liberalize their diet. This may allow them the health benefits of a high-potassium diet without the increased risk for hyperkalemia, although further studies are needed.

Reno-protective effects of oral alkalizing agents in chronic kidney disease with aciduria: protocol for a randomized cohort study

Background

Aciduria caused by urinary excretion of acidic metabolic wastes produced in daily life is known to be augmented in patients with chronic kidney disease (CKD). To evaluate the reno-protective effect of oral alkalizing agents for the improvement of metabolic acidosis and neutralization of intratubular pH in the patients with mild stages of CKD. Also, to identify reno-protective surrogate markers in the serum and urine that can closely associate the effect of urine alkalization.

Methods

In this single-centered, open-labeled, randomized cohort study, patients with CKD stages G2, G3a and G3b, who visited and were treated at Tohoku University Hospital during the enrollment period were registered. We administered sodium bicarbonate or sodium-potassium citrate as the oral alkalinizing agents. A total of 150 patients with CKD will be randomly allocated into the following three groups: sodium bicarbonate, sodium-potassium citrate and standard therapy group without any alkalinizing agents. The data of performance status, venous blood test, spot urine test, venous blood-gas test, electrocardiogram, renal arterial ultrasonography and chest X-ray will be collected at 0, 6, 12 and 24 weeks (short-term study) from starting the interventions. These data will be also collected at 1 and 2 years (long-term study). The samples of plasma and serum and early-morning urine at every visit will be acquired for the analysis of renal function and surrogate uremic biomarkers.

The recruitment for this cohort study terminated in March, 2018, and the follow-up period for all the enrolled subjects will be terminated in December, 2020. The primary endpoint will be the development of originally-defined significant renal dysfunction or the occurrence of any cerebrovascular disease in the short-term study. The secondary endpoint will be the same endpoints as in the long-term study, or the patients with significant changes in the suggested the surrogate biomarkers.

Discussion

The findings of this study will address the importance of taking oral alkalizing agents in the patients with early stages of CKD, furthermore they could address any new surrogate biomarkers that can be useful from early stage CKD.

Trial registration

Registered Report Identifier: UMIN000010059 and jRCT021180043.

The trial registration number; 150.

Date of registration; 2013/02/26.

Adverse Effects of Autoclaved Diets on the Progression of Chronic Kidney Disease and Chronic Kidney Disease-Mineral Bone Disorder in Rats

BACKGROUND

Autoclaving rodent diets is common in laboratory animals, but autoclaving increases the formation of dietary advanced glycation end-products (AGE). We studied the effect of autoclaved (AC) diet alone or in combination with a diet high in bioavailable phosphorus on biochemistries of chronic kidney disease-mineral and bone disorder (CKD-MBD), intestinal gene expression, and oxidative stress.

METHODS

Male CKD rats (Cy/+) and normal littermates were fed 1 of 3 diets: AC 0.7% phosphorus grain-based diet for 28 weeks (AC); AC diet for 17 weeks followed by non-autoclaved (Non-AC) 0.7% phosphorus casein diet until 28 weeks (AC + Casein); or Non-AC diet for 16 weeks followed by a Non-AC purified diet until 30 weeks (Non-AC + Casein).

RESULTS

AC diets contained ~3× higher AGEs and levels varied depending on the location within the autoclave. Rats fed the AC and AC + Casein diets had higher total AGEs and oxidative stress, irrespective of kidney function. Kidney function was more severely compromised in CKD rats fed AC or AC + Casein compared to Non-AC + Casein. There was a disease-by-diet interaction for plasma phosphorus, parathyroid hormone, and c-terminal fibroblast growth factor-23, driven by high values in the CKD rats fed the AC + Casein diet. Compared to Non-AC + Casein, AC and AC + Casein-fed groups had increased expression of receptor of AGEs and intestinal NADPH oxidase dual oxidase-2, independent of kidney function.

CONCLUSIONS

Autoclaving rodent diets impacts the progression of CKD and CKD-MBD, highlighting the critical importance of standardizing diets in experiments.

Serum xanthophyll carotenoids are associated with estimated glomerular filtration rate in an aged cohort

Progressive renal decline is associated with increasing oxidative stress. However, the majority of studies have investigated endogenous antioxidants in predominantly advanced stages of kidney disease. Many traditional risk factors associated with renal dysfunction have been linked with cognitive decline as the kidneys and brain share comparable anatomic and haemodynamic characteristics that leave them susceptible to common pathogenic mechanisms. The objective of this study was to examine serum dietary antioxidants and their association with renal function characterised by estimated glomerular filtration rate (eGFR) in a cross-sectional analysis of 570 participants. High performance liquid chromatography quantified serum levels of retinol, α-tocopherol, γ-tocopherol and six carotenoids (α-carotene, β-carotene, β-cryptoxanthin, lutein, lycopene and zeaxanthin) in participants. Multiple regression analyses were used to evaluate associations while adjusting for potential confounders. A sensitivity analysis was performed in cognitively-intact participants only. Serum levels of the xanthophyll carotenoid lutein were positively associated with eGFR in analyses adjusted for age (years), gender, smoking, APOE4 status and Alzheimer’s disease. Retinol was inversely associated with eGFR, although was no longer significant in the smaller sensitivity analysis. Our findings identify significant associations between the xanthophyll carotenoids and eGFR. Further investigations are required to confirm these findings.

Cholesterol Disturbances and the Role of Proper Nutrition in CKD Patients

Chronic kidney disease (CKD) is a widespread disease with increasing prevalence in the modern society. Lipid disturbances are common in this group of patients. In most patients with CKD atherogenic dyslipidemia is observed. Dyslipidemia in patients with renal diseases increases the risk of cardiovascular diseases and it accelerates the progression of chronic kidney disease to its end stage. The amelioration of dyslipidemia and the lowering of oxidative stress, inflammatory processes, insulin sensitivity and remnant lipoproteins levels may lead to the reduction in cardiovascular burden. Nutritional interventions can strengthen the beneficial effect of treatment and they play an important role in the preservation of overall well-being of the patients with CKD since the aim of appropriate diet is to reduce the risk of cardiovascular events, prevent malnutrition, and hamper the progression of kidney disease. The management of dyslipidemia, regardless of the presence of chronic kidney disease, should be initiated by the introduction of therapeutic lifestyle changes. The introduction of diet change was shown to exert beneficial effect on the lipid level lowering that reaches beyond pharmacological therapy. Currently available evidence give the impression that data on dietary interventions in CKD patients is not sufficient to make any clinical practice guidelines and is of low quality.

Diet and Chronic Kidney Disease

Kidney disease affects almost 15% of the US population, and prevalence is anticipated to grow as the population ages and the obesity epidemic continues due to Western dietary practices. The densely caloric Western diet, characterized by high animal protein and low fruit and vegetable content, has fueled the growth of chronic diseases, including chronic kidney disease. The glomerulus or filtering unit of the kidney is very susceptible to barotrauma, and diets high in animal protein impede the glomerulus' ability to protect itself from hemodynamic injury. High animal protein intake combined with low intake of fruits and vegetables also leads to a high net endogenous acid production requiring augmentation of ammonium excretion in order to prevent acidosis. This higher workload of the kidney to maintain a normal serum bicarbonate level may further exacerbate kidney disease progression. This article reviews the potential mechanisms whereby several key characteristics of the typical Western diet may impact kidney disease incidence and progression. Reducing animal protein intake and egg yolk and increasing intake of fruits and vegetables and fiber may prevent or delay end-stage renal disease, but few clinical trials have examined vegetarian diets for management of chronic kidney disease. More research is needed to determine optimal dietary patterns for the prevention of kidney disease and its progression.

Multidisciplinary Chronic Kidney Disease Clinic Practices: A Scoping Review

Background:

Multidisciplinary chronic kidney disease (CKD) clinics improve patient outcomes but their optimal design is unclear.

Objective:

To perform a scoping review to identify and describe current practices (structure, function) associated with multidisciplinary CKD clinics.

Design:

Scoping review.

Setting:

Databases included Medline, EMBASE, Cochrane, and CINAHL.

Patients:

Patients followed in multidisciplinary CKD clinics globally.

Measurements:

Multidisciplinary CKD clinic composition, entry criteria, follow-up, and outcomes.

Methods:

We systematically searched the literature to identify randomized controlled trials, non-randomized interventional studies, or observational studies of multidisciplinary CKD clinics defined by an outpatient setting where two or more allied health members (with or without a nephrologist) provided longitudinal care to 50 or more adult or pediatric patients with CKD. Included studies were from 2002 to present. Searches were completed on August 10, 2018. Title, abstracts, and full texts were screened independently by two reviewers with disagreements resolved by a third. We abstracted data from included studies to summarize multidisciplinary CKD clinic team composition, entry criteria, follow-up, and processes.

Results:

40 studies (8 randomized controlled trials and 32 non-randomized interventional studies or observational studies) involving 23 230 individuals receiving multidisciplinary CKD care in 12 countries were included. Thirty-eight focused on adults (27 with CKD, 10 incident dialysis patients, one conservative therapy) while two studies focused on adolescents or children with CKD. The multidisciplinary team included a mean of 4.6 (SD 1.5) members consisting of a nephrologist, nurse, dietician, social worker, and pharmacist in 97.4%, 86.8%, 84.2%, 57.9%, and 42.1% of studies respectively. Entry criteria to multidisciplinary CKD clinics ranged from glomerular filtration rates of 20 to 70 mL/min/1.73m² or CKD stages 1 to 5 without any proteinuria or risk equation-based criteria. Frequency of follow-up was variable by severity of kidney disease. Team member roles and standardized operating procedures were infrequently reported.

Limitations:

Unstandardized definition of multidisciplinary CKD care, studies limited to CKD defined by glomerular filtration rate, and lack of representation from countries other than Canada, Taiwan, the United States, and the United Kingdom.

Conclusions:

There is heterogeneity in multidisciplinary CKD team composition, entry criteria, follow-up, and processes with inadequate reporting of this complex intervention. Additional research is needed to determine the best model for multidisciplinary CKD clinics.

Trial registration:

Not applicable.

Serum albumin and hospitalization among pediatric patients with end-stage renal disease who started dialysis therapy

BACKGROUND

Hypoalbuminemia is a strong predictor of hospitalization and mortality among adult dialysis patients. However, data are scant on the association between serum albumin and hospitalization among children new to dialysis.

METHODS

In a retrospective cohort study of children 1-17 years old with end-stage renal disease receiving dialysis therapy in a large US dialysis organization 2007-2011, we examined the association of serum albumin with hospitalization frequency and total hospitalization days using a negative binomial regression model.

RESULTS

Among 416 eligible patients, median (interquartile range) age was 14 (10-16) years and mean ± SD baseline serum albumin level was 3.7 ± 0.8 g/dL. Two hundred sixty-six patients (64%) were hospitalized during follow-up with an incidence rate of 2.2 (95%CI, 1.9-2.4) admissions per patient-year. There was a U-shaped association between serum albumin and hospitalization frequency; hospitalization rates (95%CI) were 2.7 (2.2-3.2), 1.9 (1.5-2.4), 1.6 (1.3-1.9), and 2.7 (1.7-3.6) per patient-year among patients with serum albumin levels < 3.5, 3.5- < 4.0, 4.0- < 4.5, and ≥ 4.5 g/dL, respectively. Case mix-adjusted hospitalization incidence rate ratios (IRRs) (95%CI) were 1.63 (1.24-2.13), 1.32 (1.10-1.58), and 1.25 (1.06-1.49) at serum albumin levels 3.0, 3.5, and 4.5 g/dL, respectively (reference: 4.0 g/dL). Similar trends were observed in hospitalization days. These associations remained robust against further adjustment for laboratory variables associated with malnutrition and inflammation.

CONCLUSIONS

Both high and low serum albumin were associated with higher hospitalization in children starting dialysis. Because the observed association is novel and not fully explainable especially for high serum albumin levels, interpreting the results requires caution and further studies are needed to confirm and elucidate this association before clinical recommendations are made.

European ADPKD Forum multidisciplinary position statement on autosomal dominant polycystic kidney disease care: European ADPKD Forum and Multispecialist Roundtable participants

Autosomal dominant polycystic kidney disease (ADPKD) is a chronic, progressive condition characterized by the development and growth of cysts in the kidneys and other organs and by additional systemic manifestations. Individuals with ADPKD should have access to lifelong, multidisciplinary, specialist and patient-centred care involving: (i) a holistic and comprehensive assessment of the manifestations, complications, prognosis and impact of the disease (in physical, psychological and social terms) on the patient and their family; (ii) access to treatment to relieve symptoms, manage complications, preserve kidney function, lower the risk of cardiovascular disease and maintain quality of life; and (iii) information and support to help patients and their families act as fully informed and active partners in care, i.e. to maintain self-management approaches, deal with the impact of the condition and participate in decision-making regarding healthcare policies, services and research. Building on discussions at an international roundtable of specialists and patient advocates involved in ADPKD care, this article sets out (i) the principles for a patient-centred, holistic approach to the organization and delivery of ADPKD care in practice, with a focus on multispecialist collaboration and shared-decision making, and (ii) the rationale and knowledge base for a route map for ADPKD care intended to help patients navigate the services available to them and to help stakeholders and decision-makers take practical steps to ensure that all patients with ADPKD can access the comprehensive multispecialist care to which they are entitled. Further multispecialty collaboration is encouraged to design and implement these services, and to work with patient organizations to promote awareness building, education and research.

Dietary Care for ADPKD Patients: Current Status and Future Directions

Autosomal dominant polycystic kidney disease (ADPKD) is the most common genetic nephropathy, and tolvaptan is the only therapy available. However, tolvaptan slows but does not stop disease progression, is marred by polyuria, and most patients worldwide lack access. This and recent preclinical research findings on the glucose-dependency of cyst-lining cells have renewed interest in the dietary management of ADPKD. We now review the current dietary recommendations for ADPKD patients according to clinical guidelines, the evidence base for those, and the potential impact of preclinical studies addressing the impact of diet on ADPKD progression. The clinical efficacy of tolvaptan has put the focus on water intake and solute ingestion as modifiable factors that may impact tolvaptan tolerance and ADPKD progression. By contrast, dietary modifications suggested to ADPKD patients, such as avoiding caffeine, are not well supported and their impact is unknown. Recent studies have identified a chronic shift in energy production from mitochondrial oxidative phosphorylation to aerobic glycolysis (Warburg effect) as a contributor to cyst growth, rendering cyst cells exquisitely sensitive to glucose availability. Therefore, low calorie or ketogenic diets have delayed preclinical ADPKD progression. Additional preclinical data warn of potential negative impact of excess dietary phosphate or oxalate in ADPKD progression.