Chronic kidney disease (CKD) and low bone mineral density (BMD) are highly prevalent and can co-exist. Parameters of mineral metabolism are associated with BMD in CKD, but other contributing factors may contribute. The aim of this study was to assess changes in BMD and its determinants in patients with non-dialysis-dependent CKD (NDD-CKD). Body composition and biochemical profiles were assessed in a retrospective hospital-based cohort study of patients with NDD-CKD. BMD, lean soft tissue (LST), appendicular LST (ALST), and percentage fat mass were assessed by dual-energy X-ray absorptiometry (DXA). ALST index (ALSTI, ALST/height2) and load-capacity index (LCI, fat mass/LST) were calculated. Low BMD was defined as t-score ≤-1.0. Mean time between assessments was 2.8±1.3 years, 46 patients were included. A reduction in renal function was observed. Changes in body composition included reductions in ALST (p=0.031), ALSTI (p=0.021) and a trend for BMD (p=0.053); and an increase in percentage fat mass (p=0.044) and LCI (p=0.032). Females had a reduction in BMD (p=0.034), ALST (p=0.026), and ALSTI (p=0.037). Patients with low BMD at baseline had lower LST (p=0.013), ALST (p=0.023), and percentage fat mass (p=0.037) than those with normal BMD. Additionally, reductions in LST (p=0.041), ALST (p=0.006), and ALSTI (p=0.008) were observed in patients who had low BMD at baseline, while no significant changes in body composition were observed in those with normal BMD at baseline. The following body composition parameters at baseline were determinants of BMD status at follow-up: LST (OR:0.899, 95%CI:0.829-0.976, p=0.010), ALST (OR:0.825, 95%CI:0.704-0.967, p=0.017), and ALSTI (OR:0.586, 95%CI:0.354-0.968, p=0.037), independent of fat mass, and LCI. Detrimental body composition changes were observed without changes in body weight; these were more significant in females. Moreover, this is the first longitudinal study showing a protective effect of LST against BMD loss in patients with NDD-CKD.

ObjectiveThe clinical impact of malnutrition based on the Global Leadership Initiative on Malnutrition (GLIM) criteria in patients with kidney dysfunction remains poorly understood. This study investigated the usefulness of GLIM criteria for malnutrition predicting mortality in patients with kidney dysfunction and different clinical renal states, including no kidney disease (NKD), acute kidney injury (AKI), and chronic kidney disease (CKD). MethodsThis single-center retrospective cohort study included 6,712 patients aged ≥18 admitted between 2018 and 2019. The relationship between the estimated glomerular filtration rate (eGFR) groups, nutritional status based on the GLIM criteria, and incidence of all-cause mortality was evaluated using multivariate Cox proportional hazards (CPH) models. Malnutrition was defined as at least one phenotype (weight loss, low body mass index (BMI), or reduced muscle mass) and one etiological criterion (reduced intake/assimilation or disease burden/inflammation). ResultsMultivariate CPH models showed that eGFR ≤29 (vs. eGFR: 60–89, adjusted HR = 1.84, 95% CI: 1.52–2.22), 30–59 (vs. eGFR: 60–89, adjusted HR = 1.40, 95% CI: 1.20–1.64), and ≥90 (vs. eGFR: 60–89, adjusted HR = 1.40, 95% CI: 1.14–1.71), moderate and severe malnutrition (vs. without malnutrition, adjusted HR = 1.38 [1.18–1.62] and 2.18 [1.86–2.54], respectively) were independently associated with the incidence of death. The all-cause mortality rate was higher in patients with malnutrition or eGFR ≤29 (adjusted HR, 3.31; 95% CI: 2.51–4.35) than in patients without malnutrition or eGFR 60–89. Furthermore, moderate and severe malnutrition (vs. no malnutrition) was independently associated with death in patients with NKD, AKI, and CKD. ConclusionMalnutrition based on the GLIM criteria was associated with increased all-cause mortality in inpatients, and malnutrition combined with kidney dysfunction was associated with a higher risk of mortality. Furthermore, patients with NKD, AKI, and CKD showed an association between malnutrition based on GLIM criteria and mortality.

Trimethylamine N-oxide (TMAO) is a gut bacteria mediated liver metabolite of dietary betaine, choline, and carnitine which is excreted by glomerular filtration. We studied whether TMAO is associated with cardiovascular disease (CVD) in patients with chronic kidney disease (CKD). Among 478 patients with CKD stage G2 (n = 104), G3a (n = 163), G3b (n = 123), and G4 (n = 88), we studied the association between fasting plasma concentrations of TMAO, choline or betaine at baseline and kidney function, prevalent CVD and future renal outcomes during a mean follow-up of 5.1 years. Decreased glomerular filtration rate was associated with higher plasma concentrations of TMAO, choline and betaine. Baseline concentrations of TMAO were higher in participants with preexisting CVD compared to those without CVD (8.4 [10.1] vs. 7.8 [8.0] μmol/L; p = 0.047), but the difference was not significant after adjusting for confounders. During the follow up, 147 participants experienced CVD or died and 144 reached the predefined renal endpoint. In the adjusted regression analyses, TMAO or choline concentrations in the upper three quartiles (versus the lowest quartile) were not associated with any of the study clinical endpoints. In contrast, the adjusted hazard ratio of plasma betaine in the highest quartile versus the lowest quartile was 2.14 (1.32, 3.47) for the CVD endpoint and 1.64 (1.00, 2.67) for the renal endpoint. Elevated plasma TMAO concentrations were explained by impaired kidney function. Elevated plasma concentrations of betaine, but not that of TMAO or choline predicted adverse outcomes. TMAO might not be an appropriate target to reduce CVD or renal outcomes in patients with preexisting CKD.

ObjectiveThe Subjective Global Assessment (SGA) is a validated tool for identifying nutritional status in patients receiving maintenance dialysis (MHD), but it is not without limitations. Current research identifies additional clinical characteristics such as phase angle (PhA) associated with SGA. This study aimed to assess the overall correlation between PhA and SGA; associations between PhA and SGA by body mass index (BMI), and to identify clinical characteristics associated with SGA. Design and MethodsThis is a secondary analysis of the Rutgers Nutrition & Kidney Database, which enrolled participants from four primary studies that included adults diagnosed with chronic kidney disease who were receiving MHD. Multivariable binary logistic regression analyses were conducted to estimate odds ratio (OR) and corresponding 95% confidence intervals. ResultsThe study sample included 60.0% males with 81.1% of the sample identifying as African American. Additionally, 38.9% were obese according to the BMI classification, and 57.0% were moderately malnourished. Patients with obesity had 44% lower odds of being moderately malnourished (OR=0.56, 95% CI= 0.37, 0.85). In the model adjusted for age and ethnicity and other clinical characteristics, increasing PhA values by one unit was associated with 28% lower odds (OR= 0.72, 95% CI= 0.53, 0.97) of being moderately malnourished while increasing waist circumference (WC) values by one unit was associated with 12% higher odds (OR= 1.12; 95% CI= 1.06, 1.19) of being moderately malnourished than well-nourished. In this fully adjusted model, increasing FFM (OR= 0.95, 95% CI=0.91, 0.99) and FM (OR = 0.92, 95% CI= 0.87, 0.97) by 1 kg was also associated with a 5% and 8% lower odds of being moderately malnourished, respectively. ConclusionPhA and SGA were significantly associated only among patients classified as obese. PhA, WC, FM, and FFM were identified as potential clinical determinants of SGA. Patients receiving MHD and who have obesity may benefit from utilizing SGA along with WC, PhA, FM, and FFM to assess nutritional status.

ObjectivePrevious studies reported mixed results on associations between dietary potassium intake and hyperkalemia in patients with chronic kidney disease (CKD). This study investigated the association between potassium intake from different food sources and hyperkalemia in patients with non-dialysis-dependent CKD. MethodsA total of 285 patients were recruited at a university hospital and two city hospitals in Tokyo. Dietary potassium intake was estimated by a validated diet history questionnaire. Associations of potassium intake from all foods and individual food groups with serum potassium were examined by multivariable linear regression among potassium binder non-users. An association between tertile groups of potassium intake and hyperkalemia, defined as serum potassium ≥5.0 mEq/L, was evaluated by multivariable logistic regression. ResultsAmong 245 potassium binder non-users, total potassium intake was weakly associated with serum potassium (regression coefficient = 0.147, 95% confidence interval (CI): 0.018–0.277), while an association with hyperkalemia was not observed (first vs third tertile: adjusted odds ratio (aOR) = 0.98, 95% CI: 0.29–3.26). As for food groups, potassium intakes from potatoes, pulses, and green/yellow vegetables were positively associated with serum potassium. Patients in the highest tertile of potassium intake from potatoes had higher odds of hyperkalemia as compared to those in the lowest tertile (aOR = 4.12, 95% CI: 1.19–14.34). ConclusionTotal potassium intake was weakly associated with serum potassium, but not with hyperkalemia. Potassium intake from potatoes was associated with hyperkalemia. These findings highlight the importance of considering food sources of potassium in the management of hyperkalemia in CKD.

ObjectiveDespite adequate dialysis, the prevalence of hyperkalemia in Chinese hemodialysis(HD) patients remains elevated. This study aims to evaluate the effectiveness of a dietary recommendation system driven by Generative Pre-trained Transformers (GPTs) in managing potassium levels in HD patients. MethodsWe implemented a bespoke dietary guidance tool utilizing GPTs technology. Patients undergoing HD at our center were enrolled for the study from October 2023 to November 2023. The intervention comprised two distinct phases. Initially, patients were provided with conventional dietary education focused on potassium management in HD. Subsequently, in the second phase, they were introduced to a novel GPT-based dietary guidance tool. This AI-powered tool offered real-time insights into the potassium content of various foods and personalized dietary suggestions. The effectiveness of the AI tool was evaluated by assessing the precision of its dietary recommendations. Additionally, we compared pre-dialysis serum potassium levels and the proportion of patients with hyperkalemia among patients before and after the implementation of the GPT-based dietary guidance system. ResultsIn our analysis of 324 food photographs uploaded by 88 HD patients, the GPTs system evaluated potassium content with an overall accuracy of 65%. Notably, the accuracy was higher for high-potassium foods at 85%, while it stood at 48% for low-potassium foods. Furthermore, the study examined the effect of GPTs-based dietary advice on patients' serum potassium levels, revealing a significant reduction in those adhering to GPTs recommendations compared to recipients of traditional dietary guidance (4.57±0.76 mmol/L vs. 4.84±0.94 mmol/L, p = 0.004). Importantly, Compared to traditional dietary education, dietary education based on the GPTs tool reduced the proportion of hyperkalemia in HD patients from 39.8% to 25%(p=0.036). ConclusionThese results underscore the promising role of AI in improving dietary management for HD patients. Nonetheless, the study also points out the need for enhanced accuracy in identifying low potassium foods. It paves the way for future research, suggesting the incorporation of extensive nutritional databases and the assessment of long-term outcomes. This could potentially lead to more refined and effective dietary management strategies in HD care.

The rising global incidence of chronic inflammatory diseases calls for innovative and sustainable medical solutions. Brewers’ spent grain (BSG), a byproduct of beer production, presents a unique opportunity in this regard. This review explores the multifaceted health benefits of BSG, with a focus on managing chronic kidney disease (CKD). BSG is identified as a potent prebiotic with potential as a therapeutic agent in CKD. We emphasize the role of gut dysbiosis in CKD and discuss how BSG could help mitigate metabolic derangements resulting from dysbiosis and CKD. Fermentation of BSG further enhances its positive impact on gut health. Incorporating fermented BSG as a key component in preventive healthcare could promote a more sustainable and healthier future. By optimizing the use of this typically discarded byproduct, we can align proactive healthcare strategies with responsible resource management, benefiting both people and the environment.

ObjectiveInternet search engines and social media websites are prominent and growing sources of dietary information for people with chronic kidney disease (CKD) and their healthcare providers. However, nutrition therapy for CKD is undergoing a paradigm shift, which may lead to inconsistent advice for managing hyperphosphatemia. The aim of this study was to summarize and evaluate online resources for phosphorus-specific nutrition therapy. Design and MethodsPatient-facing resources were collected from Google, Yahoo, and Facebook in June-July 2021. Using nine independent search terms, the first 100 hits were reviewed. Dietary advice for food types, food groups, food sub-groups, and individual food items was categorized as “restricted,” “recommended,” “mixed,” and “not mentioned”. Information on publication date, source, and author(s), phosphorus bioavailability and demineralization were also collected. ResultsAfter removing duplicates, 199 resources from Google and Yahoo, and 33 from Facebook were reviewed. Resources ranged from 2005 to 2021, and were primarily authored by registered dietitians and medical doctors (65% and 31%, respectively). Dietary advice mostly focused on restricting high-phosphorus foods, and phosphorus additive-based processed foods. Dietary restrictions were generally consistent with the traditional low-phosphorus diet, which targets whole grains, Dairy, and plant-based Protein Foods, although major inconsistencies were noted. Phosphorus bioavailability and demineralization were rarely mentioned (16% and 8%, respectively). Similar findings were found on Facebook, but the limited number of resources limited meaningful comparisons. ConclusionResults showed that online resources for phosphorus-specific nutrition therapy are highly restrictive of heart healthy food items. and contain significant inconsistencies. Given the widespread and increasing use of online resources by people with CKD and healthcare professionals to inform dietary choices, efforts are urgently needed to establish consensus for phosphorus-specific nutrition therapy. Until then, the findings of this study provide a basis for increasing awareness of the potential for confusion arising from online resources.

ObjectiveThis study aimed to review the quality and content of phosphate educational materials used in pediatric chronic kidney disease. MethodsThe quality of text-based pediatric phosphate educational materials was assessed using validated instruments for health literacy demands (Suitability Assessment of Materials [SAM] and Patient Education Material Assessment Tool [PEMAT-P]) and readability (Flesch Reading Ease [FRE] and Flesch-Kincaid [FK] Grade Level). Codes were inductively derived to analyse format, appearance, target audience, resource type and content, aiming for an intercoder reliability (ICR) >80%. The content was compared to Paediatric Renal Nutrition Taskforce (PRNT) recommendations. ResultsSixty-five phosphate educational materials were obtained, 37 were pediatric-focused including 28 text-based. Thirty-two percent of text-based materials were directed at caregivers, 25% children and 43% unspecified. Most (75%) included a production date with 75% produced >2 years ago. The median FRE test-score was 68.2 (interquartile range [IQR] 61.1-75.3) and FK Grade Level 5.6 (IQR 4.5-7.7). Using SAM, 54% rated “superior” (≥70), 38% “adequate” (40-69) and 8% “not suitable” (≤39). Low scoring materials lacked a summary (12%), cover graphics (35%) or included irrelevant illustrations (50%). PEMAT-P scores were 70% (IQR 50-82) for understandability and 50% (IQR 33-67) for actionability. An ICR of 87% was achieved. Over half limited foods in agreement with PRNT (including 89% suggesting avoiding phosphate additives). Recommendations conflicting with PRNT included reducing legumes and wholegrains. Over a third contained inaccuracies and over two thirds included no practical advice. ConclusionsText-based pediatric phosphate educational materials are pitched at an appropriate level for caregivers, but this may be too high for children under 10 years. The inclusion of relevant illustrations may improve this. Three quarters of materials scored low for actionability. The advice does not always align with the PRNT, which (together with the inaccuracies reported) could result in conflicting messages to patients and their families.

ObjectiveHyperphosphatemia is a common complication in patients with kidney failure, despite the use of phosphate binders (PBs). Vitamin B3, either in the form of niacin or niacinamide (NAM), shows potential as “add-on” treatment to reduce serum phosphate concentrations in this population. NAM seems to lack many of the side-effects that are observed with niacin. The aim of this study was to investigate whether NAM is an effective and acceptable treatment in reducing serum phosphate concentrations in patients with kidney failure. MethodsDiaNia was a double-blind placebo-controlled randomised crossover trial, comparing NAM (250-500 mg/day) to placebo as “add-on” treatment to an individual treatment with approved PBs for 12 weeks in patients receiving hemodialysis. The primary outcome was serum phosphate concentrations, and the secondary outcomes were platelet counts as well as drop-outs due to side-effects. Data was analysed using both per-protocol (PP) and intention-to-treat (ITT) analyses. ResultsMean age of the PP population (n=26) was 63.6 ± 17.2 years and 53.8% were men. NAM treatment significantly reduced serum phosphate with 0.59 mg/dL (p=0.03). Linear mixed models (LMMs) demonstrated superiority of 12 weeks NAM over 12 weeks placebo with a between-treatment difference of 0.77 mg/dL (95% CI 0.010, 1.43; p=0.03). Similar results, although not significant, were found in the ITT population. We found no between-treatment differences in platelet counts and during the NAM treatment we observed three drop-outs due to side effects (8.6%). ConclusionNAM is effective in reducing serum phosphate concentrations in patients with kidney failure receiving hemodialysis. In addition, NAM is well-tolerated and seems not to increase the risk of thrombocytopenia. Thus, NAM can be valuable as “add-on” treatment to combat hyperphosphatemia in patients with kidney failure. However, more research in larger populations is needed to confirm this.