RESUMO
BACKGROUND AND OBJECTIVES: Nutrition intervention is an essential component of kidney disease management. This study aimed to understand current global availability and capacity of kidney nutrition care services, interdisciplinary communication, and availability of oral nutrition supplements. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: The International Society of Renal Nutrition and Metabolism (ISRNM), working in partnership with the International Society of Nephrology (ISN) Global Kidney Health Atlas Committee, developed this Global Kidney Nutrition Care Atlas. An electronic survey was administered among key kidney care stakeholders through 182 ISN-affiliated countries between July and September 2018. RESULTS: Overall, 160 of 182 countries (88%) responded, of which 155 countries (97%) answered the survey items related to kidney nutrition care. Only 48% of the 155 countries have dietitians/renal dietitians to provide this specialized service. Dietary counseling, provided by a person trained in nutrition, was generally not available in 65% of low-/lower middle-income countries and "never" available in 23% of low-income countries. Forty-one percent of the countries did not provide formal assessment of nutrition status for kidney nutrition care. The availability of oral nutrition supplements varied globally and, mostly, were not freely available in low-/lower middle-income countries for both inpatient and outpatient settings. Dietitians and nephrologists only communicated "sometimes" on kidney nutrition care in ≥60% of countries globally. CONCLUSIONS: This survey reveals significant gaps in global kidney nutrition care service capacity, availability, cost coverage, and deficiencies in interdisciplinary communication on kidney nutrition care delivery, especially in lower-income countries.
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Suplementos Nutricionais , Nefropatias/terapia , Terapia Nutricional , Estudos Transversais , Saúde Global , Pesquisas sobre Atenção à Saúde , HumanosRESUMO
INTRODUCTION: The achievement of erythropoiesis in hemodialysis (HD) patients is typically managed with erythropoiesis-stimulating-agents (ESA's) and intravenous iron (IV-iron). Using this treatment strategy, HD patients frequently show an elevated fraction of red blood cells (RBC) with hemoglobin (Hb) content per cell that is below the normal range, called hypochromic RBC. The low Hb content per RBC is the result of the clinical challenge of providing sufficient iron content to the bone marrow during erythropoiesis. Vitamin C supplements have been used to increase Hb levels in HD patients with refractory anemia, which supports the hypothesis that vitamin C mobilizes iron needed for Hb synthesis. METHODS: We conducted a cross-sectional survey in 149 prevalent HD patients of the percent hypochromic RBC, defined as RBC with Hb < 300 ng/uL of packed RBC, in relation to plasma vitamin C levels. We also measured high-sensitivity CRP, (hs-CRP), iron, and ferritin levels. and calculated ESA dose. FINDINGS: High plasma levels of vitamin C were negatively associated with hypochromic RBC (P < 0.003), and high ESA doses were positively associated (P < 0.001). There was no significant association of hs-CRP with percent hypochromic RBC. DISCUSSION: This finding supports the hypothesis that vitamin C mobilizes iron stores, improves iron delivery to the bone marrow, and increase the fraction of RBC with normal Hb content. Further research is warranted on development of protocols for safe and effective use of supplemental vitamin C for management of renal anemia.
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Ácido Ascórbico/metabolismo , Eritrócitos/metabolismo , Hemoglobinas/análise , Falência Renal Crônica/sangue , Diálise Renal/métodos , Estudos Transversais , Humanos , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-IdadeRESUMO
Protein energy wasting (PEW) is common in patients with chronic kidney disease (CKD) and is associated with adverse clinical outcomes, especially in individuals receiving maintenance dialysis therapy. A multitude of factors can affect the nutritional and metabolic status of CKD patients requiring a combination of therapeutic maneuvers to prevent or reverse protein and energy depletion. These include optimizing dietary nutrient intake, appropriate treatment of metabolic disturbances such as metabolic acidosis, systemic inflammation, and hormonal deficiencies, and prescribing optimized dialytic regimens. In patients where oral dietary intake from regular meals cannot maintain adequate nutritional status, nutritional supplementation, administered orally, enterally, or parenterally, is shown to be effective in replenishing protein and energy stores. In clinical practice, the advantages of oral nutritional supplements include proven efficacy, safety, and compliance. Anabolic strategies such as anabolic steroids, growth hormone, and exercise, in combination with nutritional supplementation or alone, have been shown to improve protein stores and represent potential additional approaches for the treatment of PEW. Appetite stimulants, anti-inflammatory interventions, and newer anabolic agents are emerging as novel therapies. While numerous epidemiological data suggest that an improvement in biomarkers of nutritional status is associated with improved survival, there are no large randomized clinical trials that have tested the effectiveness of nutritional interventions on mortality and morbidity.
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Metabolismo Energético , Estado Nutricional , Apoio Nutricional , Desnutrição Proteico-Calórica/prevenção & controle , Desnutrição Proteico-Calórica/terapia , Diálise Renal , Insuficiência Renal Crônica/terapia , Anabolizantes/uso terapêutico , Estimulantes do Apetite/uso terapêutico , Terapia Combinada , Comorbidade , Suplementos Nutricionais , Metabolismo Energético/efeitos dos fármacos , Exercício Físico , Humanos , Desnutrição Proteico-Calórica/diagnóstico , Desnutrição Proteico-Calórica/etiologia , Diálise Renal/efeitos adversos , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/diagnóstico , Fatores de Risco , Resultado do TratamentoRESUMO
BACKGROUND: Hyperphosphatemia has been identified in the past decade as a strong predictor of mortality in advanced chronic kidney disease (CKD). For example, a study of patients in stage CKD 5 (with an annual mortality of about 20%) revealed that 12% of all deaths in this group were attributable to an elevated serum phosphate concentration. Recently, a high-normal serum phosphate concentration has also been found to be an independent predictor of cardiovascular events and mortality in the general population. Therefore, phosphate additives in food are a matter of concern, and their potential impact on health may well have been underappreciated. METHODS: We reviewed pertinent literature retrieved by a selective search of the PubMed and EU databases (www.zusatzstoffe-online.de, www.codexalimentarius.de), with the search terms "phosphate additives" and "hyperphosphatemia." RESULTS: There is no need to lower the content of natural phosphate, i.e. organic esters, in food, because this type of phosphate is incompletely absorbed; restricting its intake might even lead to protein malnutrition. On the other hand, inorganic phosphate in food additives is effectively absorbed and can measurably elevate the serum phosphate concentration in patients with advanced CKD. Foods with added phosphate tend to be eaten by persons at the lower end of the socioeconomic scale, who consume more processed and "fast" food. The main pathophysiological effect of phosphate is vascular damage, e.g. endothelial dysfunction and vascular calcification. Aside from the quality of phosphate in the diet (which also requires attention), the quantity of phosphate consumed by patients with advanced renal failure should not exceed 1000 mg per day, according to the guidelines. CONCLUSION: Prospective controlled trials are currently unavailable. In view of the high prevalence of CKD and the potential harm caused by phosphate additives to food, the public should be informed that added phosphate is damaging to health. Furthermore, calls for labeling the content of added phosphate in food are appropriate.
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Aditivos Alimentares/efeitos adversos , Hiperfosfatemia/induzido quimicamente , Fosfatos/efeitos adversos , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/mortalidade , Relação Dose-Resposta a Droga , Fast Foods/efeitos adversos , Rotulagem de Alimentos , Humanos , Hiperfosfatemia/sangue , Hiperfosfatemia/mortalidade , Absorção Intestinal/fisiologia , Falência Renal Crônica/sangue , Falência Renal Crônica/mortalidade , Expectativa de Vida , Taxa de Depuração Metabólica/fisiologia , Necessidades Nutricionais , Fosfatos/sangue , Fatores SocioeconômicosRESUMO
BACKGROUND: Maintenance haemodialysis patients often suffer from secondary hyperparathyroidism and serum parathyroid hormone levels may be influenced by nutritional variables. METHODS: We examined serum bio-intact parathyroid hormone (BiPTH) and plasma vitamin C in 117 chronic haemodialysis patients. Plasma vitamin C was measured by high-performance liquid chromatography with electrochemical detection, on samples collected before start of the dialysis treatment. RESULTS: Plasma vitamin C showed a significant positively skewed distribution, ranging from <2 microM to >300 microM. We found 15% (n = 17) of the patients with severe vitamin C deficiency (<10 microM), 66% (n = 77) in the range 10-80 microM, and 19% (n = 23) with plasma vitamin C >80 microM, the upper limit of normal for non-renal disease population. High plasma vitamin C was associated with lower plasma BiPTH (P = 0.005, one-way analysis of variance), and this association persisted after stepwise multiple regression for other factors known to influence PTH. Low vitamin C levels were also associated with increased serum alkaline phosphatase, a further indicator of the impact of vitamin C status on bone metabolism. Patients who reported dietary vitamin C intake of >or=100 mg/day had lower BiPTH (P = 0.015), consistent with findings from plasma measurements of vitamin C. This novel observation of the interaction between PTH and vitamin C may result from effects of vitamin C on cAMP-linked signalling pathways in bone and parathyroid gland. CONCLUSIONS: This finding does not yet warrant therapeutic intervention with supplemental vitamin C to remedy secondary hyperparathyroidism. However, further research may indicate a key interaction between vitamin C and the parathyroid hormone linked signalling pathways, and may uncover mechanisms of therapeutic importance.
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Deficiência de Ácido Ascórbico/epidemiologia , Distúrbio Mineral e Ósseo na Doença Renal Crônica/epidemiologia , Hiperparatireoidismo Secundário/epidemiologia , Diálise Renal/efeitos adversos , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Deficiência de Ácido Ascórbico/etiologia , Deficiência de Ácido Ascórbico/fisiopatologia , Distúrbio Mineral e Ósseo na Doença Renal Crônica/etiologia , Distúrbio Mineral e Ósseo na Doença Renal Crônica/fisiopatologia , Estudos Transversais , Feminino , Humanos , Hiperparatireoidismo Secundário/etiologia , Hiperparatireoidismo Secundário/fisiopatologia , Incidência , Modelos Lineares , Assistência de Longa Duração , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Probabilidade , Prognóstico , Diálise Renal/métodos , Medição de Risco , Índice de Gravidade de Doença , Distribuição por Sexo , Análise de SobrevidaRESUMO
BACKGROUND: Intravenous (IV) iron is widely prescribed for patients on haemodialysis, to replace iron losses during treatment. It releases labile iron, which can induce oxidation of vitamin C and trigger oxidant damage. We examined the stability of vitamin C in the presence of IV iron compounds. We further examined in the ability of vitamin C to release iron from these compounds. METHODS: Vitamin C was measured by high-performance liquid chromatography with electrochemical detection. Iron release from iron sucrose (FeSuc) and ferric gluconate (FeGlu) was determined with the ferrozine method. RESULTS: Vitamin C, in human plasma or fetal calf serum, was oxidized in this order of reactivity: FeSuc > FeGlu > blank reaction. FeSuc and FeGlu also oxidized vitamin C when added to freshly obtained whole human blood. During a 4 h incubation in buffer, vitamin C stimulated the release of 60% of the iron content of FeSuc at p 4, with lesser amounts at pH 3, 5 and 6, and 5% release at pH 7. Vitamin C also triggered the release of iron from FeGlu, but less release was observed than with FeSuc. Using ferrozine reagent, no iron release was detected to heparinized human plasma, following addition of 500 microM concentrations of iron compounds. CONCLUSION: Each IV-iron compound can oxidize substantial amounts of vitamin C when added to plasma or whole blood. The interaction of vitamin C is accompanied by release of iron from the particle at mildly acidic pH, which may explain the ability of high-dose vitamin C to mobilize iron from storage sites for erythropoiesis.
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Ácido Ascórbico/metabolismo , Ácido Ascórbico/farmacologia , Compostos Férricos/farmacologia , Animais , Bovinos , Interações Medicamentosas , Compostos Férricos/administração & dosagem , Óxido de Ferro Sacarado , Ácido Glucárico , Humanos , Injeções IntravenosasRESUMO
Despite advanced technology and regular and efficient dialysis treatment, the prevalence of hyperphosphatemia still is unacceptably high. Nevertheless, a neutral phosphorus balance level can generally be achieved by optimization of dialysis prescription in combination with individualized dietary and medical strategies. Besides increasing the fraction of inorganic phosphate (iP) removed by convection through the application of hemodiafiltration, extension of daily or weekly treatment time is the most promising way to neutralize phosphorus balance. Dietary phosphate restriction, the second corner stone of phosphate management, bears the risk of development of protein malnutrition. Phosphate binders (PBs) effectively reduce intestinal iP absorption, but are mostly dosed inadequately in relation to meal phosphorus content. Phosphate management may be substantially improved by enabling patients to self-adjust the PB dose to individual meal phosphate content, similar to self-adjusting insulin dose to carbohydrate intake by diabetics. A recently developed Phosphate Education Program (PEP) provides simple training tools to instruct patients to eye-estimate meal phosphorus content based on newly defined phosphorus units instead of milligrams. PEP is the first approach applying the concept of patient empowerment in the management of hyperphosphatemia in dialysis patients.
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Hemodiafiltração/métodos , Falência Renal Crônica/sangue , Distúrbios do Metabolismo do Fósforo/dietoterapia , Distúrbios do Metabolismo do Fósforo/tratamento farmacológico , Humanos , Educação de Pacientes como Assunto , Fosfatos/sangue , Fosfatos/química , Fosfatos/metabolismo , Fósforo/metabolismo , Fósforo na Dieta/farmacologia , AutocuidadoRESUMO
Hyperphosphatemia is a metabolic abnormality present in the majority of patients treated by dialysis. Inorganic phosphorus (iP) can be categorized as a true uremic toxin given its known in vivo and in vitro effects and the ability to reduce these effects by normalizing iP levels. However, despite regular and adequate dialysis treatment, the goal of normalization of phosphorus levels rarely is achieved. This article briefly evaluates the significance of hyperphosphatemia in hemodialysis patients, current therapeutic approaches, and describes a new model for evaluating the dialysis prescription for iP balance.