The role of residual renal function on potassium intake and excretion in patients on peritoneal dialysis.

BACKGROUND: Patients on chronic dialysis are at increased risk of developing disorders in potassium balance. The preservation of residual renal function (RRF), frequently observed in patients on peritoneal dialysis (PD), may contribute to better control of serum potassium. This study aimed to investigate the role residual renal function on potassium intake and excretion in PD patients. METHODS: In this cross-sectional study, dietary potassium was evaluated by the 3-day food record. Potassium concentration was determined in serum, 24 h dialysate, stool ample, and 24 h urine of patients with diuresis > 200 mL/day, who were considered non-anuric. RESULTS: Fifty-two patients, 50% men, 52.6 ± 14.0 years, and PD vintage 19.5 [7.0-44.2] months, were enrolled. Compared to the anuric group (n = 17, 33%), the non-anuric group (n = 35, 67%) had lower dialysate potassium excretion (24.8 ± 5.3 vs 30.9 ± 5.9 mEq/d; p = 0.001), higher total potassium intake (44.5 ± 16.7 vs 35.1 ± 8.1 mEq/d; p = 0.009) and potassium intake from fruit (6.2 [2.4-14.7] vs 2.9 [0.0-6.0]mEq/d; p = 0.018), and no difference in serum potassium (4.8 ± 0.6 vs 4.8 ± 0.9 mEq/L; p = 0.799) and fecal potassium (2.2 ± 0.5 vs 2.1 ± 0.7 mEq/L; p = 0.712). In non-anuric patients, potassium intake correlated directly with urinary potassium (r = 0.40; p = 0.017), but not with serum, dialysate, or fecal potassium. In the anuric group, potassium intake tended to correlate positively with serum potassium (r = 0.48; p = 0.051) and there was no correlation with dialysate or fecal potassium. CONCLUSION: The presence of residual renal function constitutes an important factor in the excretion of potassium, which may allow the adoption of a less-restrictive diet.

Effect of a Nutritional Behavioral Intervention on Intuitive Eating in Overweight Women With Chronic Kidney Disease.

OBJECTIVES: This study aimed to evaluate the impact of a nutritional behavioral intervention on intuitive eating (IE) scores of overweight non-dialysis-dependent women with chronic kidney disease and to investigate the relationship of IE scores with demographic, nutritional, and quality of life parameters in this group. DESIGN AND METHODS: This is a prospective noncontrolled clinical trial of a behavioral multisession group intervention for dietary management. Each group comprised five to eight participants in 14 weekly or biweekly sessions lasting about 90 minutes each. The IE principles were discussed during the meetings. The IE scale 2, translated and adapted to the study population, with a four-factor model was applied to assess IE attitudes. The 36-Item Short-Form Health Survey questionnaire was applied to assess health-related quality of life. RESULTS: Of the 33 patients who began participation in the study, 23 patients (median [interquartile range]: age = 62.0 years [58.0-68.0]; 52.2% with diabetes; body mass index = 32.6 kg/m2 [30.2-39.3]; estimated glomerular filtration rate = 28.0 mL/min/1.73 m2 [22.0-31.0]) completed the intervention. Except for the IE subscale Body-Food Choice Congruence, the IE total score and all its subscales (Unconditional Permission to Eat, Eating for Physical Rather than Emotional Reasons, Reliance on Hunger and Satiety Cues, and Body-Food Choice Congruence) improved after the intervention. In a cross-sectional analysis, more intuitive eaters were older and had better scores for health-related quality of life. CONCLUSIONS: The nutritional behavioral intervention embracing IE principles was effective to improve IE attitudes for this group of chronic kidney disease patients. These results are promising and may contribute to a paradigm change in the strategies to enhance motivation and adherence to dietary recommendations in this population.

Gut microbiota profile of patients on peritoneal dialysis: comparison with household contacts.

BACKGROUND: Differences in patients gut microbiota composition with the potential for dysbiosis have been associated with chronic kidney disease (CKD). However, factors other than the disease itself, such as diet and cohabitation, have not been evaluated when gut microbiota of CKD patients was compared with that of healthy controls. The aim of this study was to compare the gut microbiota composition between patients on peritoneal dialysis (PD) and age-matched household contacts with normal renal function. METHODS: Fecal samples were collected from 20 patients [men: 70%; age: 53.5 years (48.2-66; median and interquartile range); length on PD: 14 months (5.2-43.5) and 20 controls. The region V4 of the 16S ribosomal RNA gene was PCR-amplified and sequenced on Illumina MiSeq platform. Dietary intake and diet quality were assessed by a 3-day food record and a diet quality index, respectively. RESULTS: No difference was found between the gut microbiota composition of patients and controls, assessed by alpha and beta diversities (p > 0.05) and genera differential abundance (p > 0.05). The most abundant phyla in both groups were Firmicutes (PD = 45%; Control: 47%; p = 0.65) and Bacteroidetes (PD = 41%; Control: 45%; p = 0.17). The phylum Proteobacteria, known as a potential marker of gut dysbiosis, was not different in proportions between groups (p > 0.05). No difference was observed regarding diet quality and dietary intake of fiber, protein and other nutrients (p > 0.05). CONCLUSION: Gut microbiota of patients on PD did not differ from household contacts. This result suggests that cohabitation and dietary intake might have outweighed the disease influence on gut microbiota composition of our PD patients.

Effect of Unripe Banana Flour on Gut-Derived Uremic Toxins in Individuals Undergoing Peritoneal Dialysis: A Randomized, Double-Blind, Placebo-Controlled, Crossover Trial.

In chronic kidney disease (CKD), the accumulation of gut-derived metabolites, such as indoxyl sulfate (IS), p-cresyl sulfate (pCS), and indole 3-acetic acid (IAA), has been associated with the burden of the disease. In this context, prebiotics emerge as a strategy to mitigate the accumulation of such compounds, by modulating the gut microbiota and production of their metabolites. The aim of this study was to evaluate the effect of unripe banana flour (UBF-48% resistant starch, a prebiotic) on serum concentrations of IS, pCS, and IAA in individuals undergoing peritoneal dialysis (PD). A randomized, double-blind, placebo-controlled, crossover trial was conducted. Forty-three individuals on PD were randomized to sequential treatment with UBF (21 g/day) and placebo (waxy corn starch-12 g/day) for 4 weeks, or vice versa (4-week washout). The primary outcomes were total and free serum levels of IS, pCS, and IAA. Secondary outcomes were 24 h urine excretion and dialysis removal of IS, pCS, and IAA, serum inflammatory markers [high-sensitivity C-reactive protein (hsCRP), interleukin-6 (IL-6), interleukin-10 (IL-10), and tumor necrosis factor-α (TNF-α)], serum lipopolysaccharide LPS, and dietary intake. Of the 43 individuals randomized, 26 completed the follow-up (age = 55 ± 12 years; 53.8% men). UBF did not promote changes in serum levels of IS (p = 0.70), pCS (p = 0.70), and IAA (p = 0.74). Total serum IS reduction was observed in a subgroup of participants (n = 11; placebo: median 79.5 µmol/L (31-142) versus UBF: 62.5 µmol/L (31-133), p = 0.009) who had a daily UBF intake closer to that proposed in the study. No changes were observed in other secondary outcomes. UBF did not promote changes in serum levels of IS or pCS and IAA; a decrease in IS was only found in the subgroup of participants who were able to take 21g/day of the UBF.

Influence of bowel habits on gut-derived toxins in peritoneal dialysis patients.

BACKGROUND: Gut-derived uremic toxins have been associated with adverse outcomes in chronic kidney disease (CKD). Alterations in bowel habits, including constipation, seem to play an additional role in uremic toxicity. The aim of this study is to investigate the association of bowel habits with gut-derived uremic toxins and intestinal permeability in patients on automated peritoneal dialysis (APD). METHODS: This cross-sectional study enrolled 58 APD patients (age 52.5 ± 15.1 years; dialysis vintage 14.1 (6.0-36.5) months). Constipation was defined according to the Rome IV criteria. Bowel habits were assessed by the Bristol Stool Scale (BSS < 3 characterized by hard consistency of stools and/or low frequency of evacuation, a surrogate of slow intestinal transit time, and BSS ≥ 3, defining regular bowel habit). The total and free serum concentration of p-cresyl sulfate (PCS), indoxyl sulfate (IS) and indole-3-acetic acid (IAA) were dosed by high-performance liquid chromatography. Lipopolysaccharide (LPS) and zonulin were assessed by ELISA and D(-)-lactate by colorimetric method. Dietary intake was assessed by the 3-day food records. RESULTS: No differences were observed in clinical, demographic, and dietary characteristics between constipated (n = 30) and non-constipated (n = 28) groups. A trend for higher total PCS (p = 0.07) and free PCS (p = 0.06) was found in constipated patients. Patients with BSS < 3 (n = 11) exhibited significantly higher levels of total and free PCS (p < 0.01) and total IAA (p = 0.04). Conversely, No difference was found in IS levels. Except for a lower serum level of D(-)-lactate in patients with BSS < 3 (p = 0.01), zonulin and LPS levels were not different. CONCLUSIONS: Disturbed bowel habits, mainly characterized by slow transit time, may play a role in the accumulation of uremic toxins, particularly PCS, in patients on automatized peritoneal dialysis.

Diet in Chronic Kidney Disease: an integrated approach to nutritional therapy.

A healthy diet is an essential requirement to promote and preserve health, even in the presence of diseases, such as chronic kidney disease (CKD). In this review, nutritional therapy for CKD will be addressed considering not only the main nutrients such as protein, phosphorus, potassium, and sodium, which require adjustments as a result of changes that accompany the reduction of renal functions, but also the benefits of adopting dietary patterns associated with better outcomes for both preventing and treating CKD. We will also emphasize that these aspects should also be combined with a process of giving new meaning to a healthy diet so that it can be promoted. Finally, we will present the perspective of an integrated approach to the individual with CKD, exploring the importance of considering biological, psychological, social, cultural, and economic aspects. This approach has the potential to contribute to better adherence to treatment, thus improving the patient's quality of life.

Diet in Chronic Kidney Disease: an integrated approach to nutritional therapy

SUMMARY A healthy diet is an essential requirement to promote and preserve health, even in the presence of diseases, such as chronic kidney disease (CKD). In this review, nutritional therapy for CKD will be addressed considering not only the main nutrients such as protein, phosphorus, potassium, and sodium, which require adjustments as a result of changes that accompany the reduction of renal functions, but also the benefits of adopting dietary patterns associated with better outcomes for both preventing and treating CKD. We will also emphasize that these aspects should also be combined with a process of giving new meaning to a healthy diet so that it can be promoted. Finally, we will present the perspective of an integrated approach to the individual with CKD, exploring the importance of considering biological, psychological, social, cultural, and economic aspects. This approach has the potential to contribute to better adherence to treatment, thus improving the patient's quality of life.

RESUMO Uma dieta saudável é essencial para promover e preservar a saúde, mesmo na presença de doenças como a Doença Renal Crônica (DRC). Nesta revisão, a terapia nutricional para pacientes de DRC será abordada levando em conta não só os principais nutrientes que precisam ser ajustados devido às alterações que acompanham a redução das funções renais, tais como proteínas, fósforo, potássio e sódio. Abordaremos também os benefícios da adoção de padrões alimentares associados a desfechos melhores tanto para a prevenção quanto para o tratamento da DRC. Também enfatizaremos que esses aspectos devem ser aliados a um processo de ressignificação do conceito de dieta saudável para que seja possível a sua promoção. Por último, apresentaremos a perspectiva de uma abordagem integrada para o indivíduo com DRC, explorando a importância de considerar aspectos biológicos, psicológicos, sociais, culturais e econômicos. Essa abordagem tem o potencial de contribuir para uma melhor adesão ao tratamento, melhorando assim a qualidade de vida do paciente.