ABC de la diálisis peritoneal en pediatría / ABC of the peritoneal dialysis in pediatrics

Resumen: La enfermedad renal crónica terminal (ERCT) tiene una incidencia de 5,5 a 9 ppm, y una prevalencia de 23 a 65 ppm en menores de 15 años. La diálisis peritoneal (DP) crónica representa en pediatría la terapia de reemplazo renal más usada, previo al trasplante renal. Existen 2 tipos de DP crónicas, manual (DPCA) y automatizada (DPA), cuya elección se basa en las características del peritoneo eva luado mediante el test de equilibrio peritoneal (PET), que divide a los pacientes en transportadores altos (intercambio rápido), promedio alto, promedio bajo, y bajos (intercambio lento). Este test eva lúa básicamente el transporte de solutos, al cual se ha sumado el MiniPET, que evalúa el transporte peritoneal de agua libre. Se debe igualmente determinar la cuantía de diálisis (Kt/V), que representa la dosis de diálisis aplicada, con un valor mínimo sugerido de 1,7, relacionado a la morbimortalidad. Estos parámetros deben ser evaluados periódicamente para ajustar la DP, y cada vez que se sospeche una depuración o ultrafiltración inadecuadas. El objetivo de esta revisión es entregar conceptos bási cos sobre fisiología del transporte peritoneal, modalidades de DP, evaluación del transporte de agua y solutos peritoneal, y el cálculo de la dosis de diálisis para una diálisis ajustada a las necesidades de cada paciente, como también revisar los mecanismos de corrección y ajuste del procedimiento cada vez que se requiera.

Abstract: End-stage renal disease (ESRD) has an incidence of 5.5 to 9 pmp, and a prevalence of 23 to 65 pmp in children under 15 years of age. Chronic peritoneal dialysis (PD) represents the most widely used renal replacement therapy in children before kidney transplantation. There are two PD modalities, the manual one (CAPD) and the automated one (APD). The choice is based on the peritoneum characteristics, evaluated through the peritoneal equilibrium test (PET), which divides patients into high transporters (rapid exchange membrane), high average, low average, and low transporters (slow exchange membrane). This test basically evaluates the solutes transport rate, and the MiniPET has been added which evaluates peritoneal free water transport. The amount of dialysis (Kt/V), which represents the dose of dialysis administered also must be evaluated to assure a minimal value of 1.7 related to morbidity and mortality. These parameters should be evaluated periodically to ad just the PD and whenever suspected an inadequate clearance or ultrafiltration. The objective of this review is to provide basic concepts on peritoneal transport physiology, PD modalities, free water transport and peritoneal solute transport evaluation, and the dialysis dose to be applied according to the patient's needs, as well as reviewing the correction mechanisms and procedure adjustment whenever required.

Longitudinal changes in nutritional parameters and resting energy expenditure in end-stage renal disease / Alterações longitudinais nos parâmetros nutricionais e gasto energético de repouso na doença renal em estágio terminal

Abstract Aims: To evaluate the nutritional status, resting energy expenditure, caloric and protein intake, and evolution of biochemical parameters in three stages of chronic kidney disease: pre-dialytic, at the beginning of the dialysis treatment, and 30 days after starting treatment. Methods: The chi-square and Student's t tests were used to compare the variables, and analysis of repeated measurements was used to compare the data obtained in the three moments evaluated. The results were discussed at the 5% level of significance. Results: We evaluated 35 patients, 60% female and 60% with diabetes mellitus. There was a decrease in midarm circumference and serum albumin. Inflammatory state and caloric and protein intake increased. There was no significant difference in resting energy expenditure in the three moments. The serum urea and serum albumin, handgrip strength, and protein consumption after 30 days from the start of dialysis were greater in the peritoneal dialysis patients, when compared to the hemodialysis population. Conclusion: there was a decrease in midarm circumference and serum albumin and an increase in protein intake after dialysis. The peritoneal dialysis patients had higher muscle strength, even with lower protein intake. Resting energy expenditure was not different between dialysis methods and the moments evaluated.

Resumo Objetivos: Avaliar o estado nutricional, o gasto energético em repouso, o gasto calórico e proteico e a evolução dos parâmetros bioquímicos em três estágios da doença renal crônica: pré-dialítico, no início do tratamento dialítico e 30 dias após o início do tratamento. Métodos: O teste do qui-quadrado e o teste t de Student foram utilizados para comparar as variáveis, e a análise das medidas repetidas foi utilizada para comparar os dados obtidos nos três momentos avaliados. Os resultados foram discutidos ao nível de significância de 5%. Resultados: Foram avaliados 35 pacientes, 60% mulheres e 60% com diabetes mellitus. Houve uma diminuição na circunferência do terço médio do braço (CMB) e na albumina sérica. O estado inflamatório e a ingestão calórica e protéica aumentaram. Não houve diferença significativa no gasto energético em repouso nos três momentos. A ureia sérica e a albumina sérica, a força de preensão manual e o consumo de proteínas após 30 dias do início da diálise foram maiores nos pacientes em diálise peritoneal, quando comparados com a população em hemodiálise. Conclusão: houve diminuição da circunferência do terço médio do braço e na albumina sérica, e aumento da ingestão protéica após a diálise. Os pacientes em diálise peritoneal apresentaram maior força muscular, mesmo com menor consumo proteico. O gasto energético em repouso não foi diferente entre os métodos de diálise e os momentos avaliados.

Chronic Kidney Disease

SUMMARY Chronic kidney disease is highly prevalent (10-13% of the population), irreversible, progressive, and associated with higher cardiovascular risk. Patients with this pathology remain asymptomatic most of the time, presenting the complications typical of renal dysfunction only in more advanced stages. Its treatment can be conservative (patients without indication for dialysis, usually those with glomerular filtration rate above 15 ml/minute) or replacement therapy (hemodialysis, peritoneal dialysis, and kidney transplantation). The objectives of the conservative treatment for chronic kidney disease are to slow down the progression of kidney dysfunction, treat complications (anemia, bone diseases, cardiovascular diseases), vaccination for hepatitis B, and preparation for kidney replacement therapy.

Fluid and hemodynamic management in hemodialysis patients: challenges and opportunities / Manejo hídrico e hemodinâmico em pacientes em hemodiálise: desafios e oportunidades

Abstract Fluid volume and hemodynamic management in hemodialysis patients is an essential component of dialysis adequacy. Restoring salt and water homeostasis in hemodialysis patients has been a permanent quest by nephrologists summarized by the 'dry weight' probing approach. Although this clinical approach has been associated with benefits on cardiovascular outcome, it is now challenged by recent studies showing that intensity or aggressiveness to remove fluid during intermittent dialysis is associated with cardiovascular stress and potential organ damage. A more precise approach is required to improve cardiovascular outcome in this high-risk population. Fluid status assessment and monitoring rely on four components: clinical assessment, non-invasive instrumental tools (e.g., US, bioimpedance, blood volume monitoring), cardiac biomarkers (e.g. natriuretic peptides), and algorithm and sodium modeling to estimate mass transfer. Optimal management of fluid and sodium imbalance in dialysis patients consist in adjusting salt and fluid removal by dialysis (ultrafiltration, dialysate sodium) and by restricting salt intake and fluid gain between dialysis sessions. Modern technology using biosensors and feedback control tools embarked on dialysis machine, with sophisticated analytics will provide direct handling of sodium and water in a more precise and personalized way. It is envisaged in the near future that these tools will support physician decision making with high potential of improving cardiovascular outcome.

Resumo O volume de fluidos e o controle hemodinâmico em pacientes em hemodiálise é um componente essencial da adequação da diálise. A restauração da homeostase do sal e da água em pacientes em hemodiálise tem sido uma busca constante por parte dos nefrologistas, no que condiz à abordagem do "peso seco. Embora essa abordagem clínica tenha sido associada a benefícios no desfecho cardiovascular, recentemente tem sido questionada por estudos que mostram que a intensidade ou agressividade para remover fluidos durante a diálise intermitente está associada a estresse cardiovascular e dano potencial a órgãos.para remover fluidos durante a diálise intermitente está associada a estresse cardiovascular e dano potencial a órgãos. Uma abordagem mais precisa é necessária para melhorar o desfecho cardiovascular nessa população de alto risco. A avaliação e monitorização do estado hídrico baseiam-se em quatro componentes: avaliação clínica, ferramentas instrumentais não invasivas (por exemplo, US, bioimpedância, monitorização do volume sanguíneo), biomarcadores cardíacos (e.g. peptídeos natriuréticos), algoritmos e modelagem de sódio para estimar a transferência de massa. O manejo otimizado do desequilíbrio hídrico e de sódio em pacientes dialíticos consiste em ajustar a remoção de sal e líquido por diálise (ultrafiltração, dialisato de sódio), e restringir a ingestão de sal e o ganho de líquido entre as sessões de diálise. Tecnologia moderna que utiliza biosensores e ferramentas de controle de feedback, hoje parte da máquina de diálise, com análises sofisticadas, proporcionam o manejo direto sobre o sódio e a água de uma maneira mais precisa e personalizada. Prevê-se no futuro próximo que essas ferramentas poderão auxiliar na tomada de decisão do médico, com alto potencial para melhorar o resultado cardiovascular.

Effect of chronic renal dysfunction on the permeability of the colon to water and electrolytes: experimental study in rats / Efeito da disfunção renal crônica sobre a permeabilidade do cólon para água e eletrólitos: estudo experimental em ratos

ABSTRACT Background: Renal insufficiency is a disease that affects several organs by provoking hypervolemia and uremia. The disease reaches more than 500 million people worldwide and few studies bring their influence on the gastrointestinal tract. Aim: To evaluate the influence of 5/6 nephrectomy-induced hypervolemia on colonic permeability to water and electrolytes. Method: Sixty male Wistar rats weighing between 280-300 g were divided into three groups: 3, 7 and 14 days after nephrectomy, each one having a false-operated/control and partially nephrectomized. For colonic permeability they were submitted to colonic perfusion with a solution of Tyroad containing phenolphthalein. Differences among the concentrations of Na+, K+ and Cl- were used to calculate the rate of colonic permeability for the electrolytes. Phenolphthalein concentrations were used to evaluate the rate of secretion and water absorption. Results: The colonic secretion of water and electrolytes occurred expressively in the group seven days after nephrectomy. Hemodynamic and biochemical assessments determined the progression of renal failure in all three groups and polyethylene glycol was shown to be effective in reversing the secretory capacity of the colon. Conclusion: Hypervolemia established after 7 days post-nephrectomy 5/6 caused marked colonic secretion for water and electrolytes. The organism presents progressive colonic secretion as the blood volume increases; on the other hand, polyethylene glycol was able to revert this secretory framework of the colon to water and electrolytes by reversing the hypervolemia.

RESUMO Racional: A insuficiência renal é doença que afeta diversos órgãos por provocar hipervolemia e quadro urêmico ao organismo. A doença atinge mais de 500 milhões de pessoas em todo o mundo, e poucos estudos trazem sua influência sobre o trato gastrointestinal. Objetivo: Avaliar a influência da hipervolemia induzida pela nefrectomia 5/6 sobre a permeabilidade colônica para água e eletrólitos. Método: Foram utilizados 60 ratos machos Wistar, pesando entre 280-300 g divididos em três grupos: 3, 7 e 14 dias de pós-nefrectomia. Cada grupo foi formado por um controle e outro parcialmente nefrectomizado. Para os estudos de permeabilidade colônica, os animais foram submetidos à perfusão colônica com solução de Tyroad contendo fenolftaleína por 60 min. Diferenças entre as concentrações de Na+, K+, e Cl- foram utilizadas para calcular a taxa de permeabilidade colônica para os eletrólitos e as de fenolftaleína para avaliar a taxa de secreção e absorção de água. Resultados: A secreção colônica de água e eletrólitos ocorreu de forma expressiva no grupo 7 dias pós-nefrectomia. Avaliações hemodinâmicas e bioquímicas determinaram a evolução da insuficiência renal nos três grupos e o polietilenoglicol mostrou-se eficaz na reversão da capacidade secretora do cólon. Conclusão: O quadro de hipervolemia estabelecido a partir dos sete dias pós-nefrectomia 5/6 provocou acentuada secreção colônica para água e eletrólitos. O organismo apresenta secreção colônica progressiva a medida que aumenta a volemia sanguínea; por outro lado, o polietilenoglicol foi capaz de reverter esse quadro secretor do cólon para água e eletrólitos por reverter o quadro hipervolêmico.

The effect of hemodialysis on the body composition and cardiovascular disease markers in recently diagnosed end stage renal disease patients

SUMMARY AIM: Uremic toxins and excess fluid contributes to increased cardiovascular (CV) risk. We aimed to determine the body fluid status in patients who are just starting hemodialysis (HD) and to determine the effects of excess fluid removed by HD on the CV system. METHODS: A total of 52 patients with chronic kidney disease (CKD) who had just started HD were included. Before the HD, the left atrial diameter was measured, the volumes were calculated, the pulse wave velocity (PWV) and the augmentation index (AIx) were measured, the bioimpedance analysis (BIA) was performed, the blood was taken for brain natriuretic peptide (BNP). When patients reached their dry weight with HD, the same measurements were repeated. RESULTS: Measurements were made to determine the volume status, and all parameters except the fat tissue index decreased significantly after HD. With the removal of fluid by HD, there was an average weight reduction of 4.38 kilograms. Positive correlations between PWV and age and cardiothoracic ratio (CTR) before HD were determined. Negative correlations were found between PWV and lean tissue mass (LTM) and intracellular water (ICW) before HD. At the end of the last HD, PWV was positively correlated with age, CTR, central pulse pressure Correlation between pulse wave velocity and LTI was negative CONCLUSIONS: HD significantly improves PWV in patients reaching dry weight. Reduction of fluid excess by ultrafiltration in HD patients may reduce CV mortality by reducing arterial stiffness.

RESUMO INTRODUÇÃO: Em pacientes com doença renal crônica (DRC), toxinas urêmicas e hipervolemia contribuem para aumentar o risco cardiovascular. Nosso objetivo foi determinar o estado de hidratação em pacientes com DRC iniciando hemodiálise (HD) e avaliar os efeitos da correção da hipervolemia sobre o sistema cardiovascular. MÉTODOS: Foram incluídos 52 pacientes que haviam acabado de iniciar HD. Antes do início da sessão, foram determinados o diâmetro e o volume atrial esquerdo, a velocidade de onda de pulso (VOP) e o índice de amplificação sistólica ("augmentation index", AI). Além disso, realizamos análise da composição corporal por bioimpedância elétrica (BIA) e mensuramos os níveis plasmáticos de peptídeo natriurético tipo B. Os mesmos procedimentos foram repetidos após os pacientes alcançarem o "peso seco". RESULTADOS: O peso corporal dos pacientes foi reduzido, em média, em 4,38 kg. Na BIA, todos os parâmetros, exceto o índice de gordura corporal, foram significativamente reduzidos após a hemodiálise. Antes da HD, a VOP se correlacionou positivamente com idade e razão cardiotorácica (RCT), e negativamente com a massa magra e a água intracelular. Ao final da hemodiálise, a VOP se correlacionou positivamente com idade, RCTe pressão de pulso central, correlacionando-se negativamente com a Lean Tissue Index (LTI). CONCLUSÃO: A hemodiálise melhora a VOP por meio da redução da volemia. O controle da hipervolemia via ultrafiltração pode reduzir a mortalidade cardiovascular por meio da redução da rigidez arterial.

Association between syndecan-1 and renal function in adolescents with excess weight: evidence of subclinical kidney disease and endothelial dysfunction

Excess weight (overweight and obesity) is associated with kidney and cardiovascular disease. The aim of this study was to investigate the association between syndecan-1 and renal function among adolescents with excess weight. A total of 56 students from a public school at Fortaleza, CE, Brazil, were investigated. The adolescents were submitted to anthropometric evaluation, including weight, height, blood pressure and body mass index. Blood and urine samples were collected for the determination of serum lipids (total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, triglycerides), and the endothelial injury biomarker syndecan-1. Participants' mean age was 16±1 years (range 14-19 years), and 68% were females. Overweight was observed in 4 cases (7.1%) and obesity in 7 (12.5%). Changes in serum lipid levels were more frequent in the overweight group. A positive correlation between syndecan-1 and serum creatinine (r=0.5, P=0.001) and triglycerides (r=0.37, P=0.004), and a negative correlation with glomerular filtration rate (r=-0.33, P=0.02) were found. These findings suggest that adolescents with excess weight present incipient changes at the cellular level that make them more vulnerable to the development of kidney and cardiovascular diseases.

Clinical trial for the control of water intake of patients undergoing hemodialysis treatment / Ensaio clínico para o controle da ingestão hídrica de pacientes em tratamento hemodialítico * / Ensayo clínico para el control de la ingestión hídrica de pacientes en tratamiento hemodialítico

ABSTRACT Objective: to analyze the impact of an educational and motivational intervention for patients with a chronic kidney disease, undergoing hemodialysis treatment, on the control of fluid intake during interdialytic periods. Method: a quasi-experimental, non-randomized clinical trial with patients from a Nephrological Unit of the State of São Paulo. Participants were included in two groups: Control Group with 106 patients and Intervention Group with 86 patients, totaling 192 participants. The used intervention was an educational and motivational video to control liquid intake, based on the Bandura's Theory. The measure of control of water intake was the percentage of lost weight, also considered the variable outcome of the research. For the data analysis, descriptive analyses and regression analysis of the Inflated Beta Model were used. Results: patients who participated in the intervention had a decrease in the pattern of weight gain in interdialytic periods, with a 3.54 times more chance of reaching the goal of 100% of weight loss when compared to participants from the control group. Conclusion: the educational and motivational intervention was effective in reducing the percentage of weight loss in patients undergoing hemodialysis. Brazilian Clinical Trials Registry (ReBEC) under the opinion RBR-4XYTP6.

RESUMO Objetivo: analisar o impacto de uma intervenção educativa e motivacional para pacientes com doença renal crônica em tratamento hemodialítico, no controle do consumo de líquidos, nos períodos interdialíticos. Método: estudo quase experimental do tipo ensaio clínico não randomizado, com pacientes de uma Unidade Nefrológica no interior do Estado de São Paulo. Os participantes foram inseridos em dois grupos: Grupo Controle com 106 pacientes e Grupo Intervenção com 86 pacientes, totalizando 192 participantes do estudo. A intervenção utilizada tratou-se de um vídeo educativo e motivacional para controle do consumo de líquidos, baseado na Teoria de Bandura. A medida de controle da ingestão hídrica foi o percentual de peso perdido, também considerado a variável desfecho da pesquisa. Para a análise dos dados foram utilizadas análises descritivas e análise de regressão do Modelo Beta Inflacionado. Resultados: os pacientes que participaram da intervenção apresentaram diminuição no padrão de ganho de peso nos períodos interdialíticos, com 3,54 vezes mais chance de atingir a meta de 100% de perda de peso, comparados aos participantes do grupo controle. Conclusão: a intervenção educativa e motivacional mostrou-se efetiva na diminuição do porcentual de perda de peso dos pacientes em hemodiálise. Registro Brasileiro de Ensaios Clínicos (ReBEC), sob o parecer RBR-4XYTP6.

RESUMEN Objetivo: analizar el impacto de una intervención educativa y motivacional para pacientes con enfermedad renal crónica en tratamiento hemodialítico, en el control del consumo de líquidos, en los periodos interdialíticos. Método: estudio casi experimental del tipo ensayo clínico no aleatorio, con pacientes de una Unidad Nefrológica en el interior del Estado de São Paulo. Los participantes fueron inseridos en dos grupos: Grupo Control con 106 pacientes y Grupo Intervención con 86 pacientes, totalizando 192 participantes del estudio. La intervención utilizada se trató de un video educativo y motivacional para el control del consumo de líquidos, basado en la Teoría de Bandura. La medida de control de la ingestión hídrica fue el porcentaje de peso perdido, también considerado la variable de resultado de la investigación. Para el análisis de los datos fueron utilizados análisis descriptivos y análisis de regresión del Modelo Beta aumentado. Resultados: los pacientes que participaron de la intervención presentaron disminución en el patrón de ganancia de peso en los periodos interdialíticos, con 3,54 veces más chances de alcanzar la meta de 100% de pérdida de peso, comparados a los participantes del grupo de control. Conclusión: la intervención educativa y motivacional se mostró efectiva en la disminución del porcentaje de pérdida de peso de los pacientes en hemodiálisis. Registro Brasileño de Ensayos Clínicos (ReBEC), bajo el dictamen RBR-4XYTP6.

A study of pulmonary function in end-stage renal disease patients on hemodialysis: a cross-sectional study

ABSTRACT BACKGROUND: The aim here was to study acute effects of hemodialysis among end-stage renal disease (ESRD) patients. DESIGN AND SETTING: Prospective study in tertiary-level care center. METHODS: Fifty ESRD patients undergoing hemodialysis were studied. Spirometric pulmonary function tests were performed before and after four-hour hemodialysis sessions. RESULTS: The patients' average age was 45.8 ± 10.0 years; 64% were males and 64% had normal body mass index. Anemia (94%) and hypoalbuminemia (72%) were common. Diabetes mellitus (68%), hypertension (34%) and coronary artery disease (18%) were major comorbidities. Forty-five patients (90%) had been on hemodialysis for six months to three years. The patients' pre-dialysis mean forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1) were below normal: 45.8 ± 24.9% and 43.5 ± 25.9% of predicted, respectively. After hemodialysis, these increased significantly, to 51.1 ± 23.4% and 49.3 ± 25.5% of predicted, respectively (P < 0.01). The increase in mean FEV1/FVC, from 97.8 ± 20.8% to 99.3 ± 20.1% of predicted, was not significant (P > 0.05). The pre-dialysis mean forced expiratory flow 25-75% was 50.1 ± 31% and increased significantly, to 56.3 ± 31.6% of predicted (P < 0.05). The mean peak expiratory flow was below normal (43.8 ± 30.7%) and increased significantly, to 49.1 ± 29.9% of predicted (P < 0.05). Males and females showed similar directions of change after hemodialysis. CONCLUSIONS: Pulmonary function abnormalities are common among ESRD patients. Comparison of pre and post-hemodialysis parameters showed significant improvements, but normal predicted values were still not achieved.

Beneficial effects of intradialytic cardiopulmonary rehabilitation / Efeitos benéficos da reabilitação cardiopulmonar intradialítica

Abstract Introduction: Patients on hemodialysis (HD) present high mortality from cardiovascular complications and high morbidity, including decreasing functional capacity and quality of life. Objective: To analyze clinical and laboratory responses of patients in HD to intradialytic cardiopulmonary rehabilitation on an outpatient basis. Methods: We evaluated 14 patients in a prospective study for 8 months using cardiopulmonary rehabilitation protocol (CRehab) consisted of intradialytic aerobic exercise with a cycle ergometer. We analyzed heart rate (HR), systolic (SBP) and diastolic blood pressure (DBP), peripheral oxygen saturation (SpO2) and modified Borg scale. We evaluated cardiac function by echocardiogram, functional capacity by six minutes walk test (6MWT), and quality of life by SF-36 survey, before and after CRehab. Biochemical data and KT/Vsp were collected form medical records. Results: During CRehab, the results of HR, SBP, DBP, SpO2 and Borg scale showed no significant changes. 6MWT test showed progressive increase in the distance covered (p < 0.001) as well as a reduction in the scale of Borg post-6MWT (p = 0.009). There was no significant change in any biochemical data or in KT/Vsp. There was increase in left ventricular ejection from 65.7 ± 10.2% to 73.6 ± 10.1% (p = 0.028) and in left ventricular diastolic diameter (p = 0.027). According to SF-36 survey, patients showed improvement in three areas: physical role functioning (p = 0.012), bodily pain (p = 0.007) and vitality (p = 0.009). Conclusion: The intradialytic CRehab applied in this population was safe and allowed objective improvement of functional capacity and exercise tolerance, subjective improvement in the perception of effort, significant increase in cardiac function and better quality of life in different domains.

Resumo Introdução: Pacientes em hemodiálise (HD) têm alta mortalidade e morbidade por complicações cardiovasculares, inclusive por redução da capacidade funcional e qualidade de vida. Objetivo: Analisar a evolução clínica e laboratorial de pacientes em HD ambulatorial submetidos à reabilitação cardiopulmonar (RCP) intradialítica. Métodos: Avaliamos 14 pacientes em um estudo prospectivo por 8 meses, utilizando protocolo de RCP com exercícios aeróbicos intradialíticos. Analisamos frequência cardíaca (FC), pressão arterial sistólica (PAS) e diastólica (PAD), saturação periférica de oxigênio (SpO2) e escala de Borg modificada em todas as sessões de HD. Avaliamos função cardíaca por ecocardiograma, capacidade funcional (CF) pelo teste de caminhada de seis minutos (TC6M), e qualidade de vida pelo Questionário SF-36, antes e depois da RCP. Dados bioquímicos e de Kt/Vsp foram coletados dos prontuários. Resultados: Durante a RCP, os resultados de FC, PAS, PAD, SpO2 e escala de Borg não mostraram alterações significativas. No TC6M observamos aumento progressivo da distância percorrida (p < 0,001) e redução na escala de Borg pós-TC6M entre D0-D180 (p = 0,009). Não houve alteração significativa nos testes bioquímicos e no KT/Vsp. Houve aumento na fração de ejeção de 65,7 ± 10,2 para 73,6 ± 10,1% (p = 0,028) e no diâmetro diastólico do ventrículo esquerdo (p = 0,027). No questionário SF-36, houve melhora significativa nos domínios: limitação física (p = 0,012), dor (p = 0,007) e vitalidade (p = 0,009). Conclusão: A RCP intradialítica nesta população foi segura e permitiu melhora objetiva da CF e tolerância ao exercício, melhora subjetiva na percepção do esforço, aumento significativo da função cardíaca, bem como melhoria na qualidade de vida em diferentes domínios.

Effects of hemodialysis on corneal and anterior chamber morphometry and intraocular pressure in patients with end-stage renal disease / Efeitos da hemodiálise na morfometria da córnea e da câmara anterior, e na pressão intraocular em pacientes no estágio final da doença renal

ABSTRACT Purpose: To evaluate the effects of hemodialysis (HD) on corneal and anterior chamber morphometry, as well as intraocular pressure (IOP) in patients with end-stage renal disease. Methods: Fifty right eyes were examined 30 minutes before and after HD. IOP was measured with a Goldmann applanation tonometer, and Ehlers' formula was used to calculate the corrected IOP values. The central corneal thickness (CCT), corneal volume (CV), keratometric values, anterior chamber depth (ACD), aqueous depth (AQD), anterior chamber volume (ACV), and anterior chamber angle (ACA) in the nasal and temporal quadrants were measured with a Sirius anterior segment analysis system. Blood urea nitrogen levels, body mass, and systolic and diastolic arterial pressure were also measured before and after HD. Results: The mean age was 60.80 ± 13.38 (range: 35-80) years. The mean uncorrected and corrected IOP values decreased from 18.06 ± 3.91 and 18.31 ± 4.83 mmHg to 16.94 ± 3.87 and 16.95 ± 4.74 mmHg after HD, respectively (p=0.011 and p=0.003, respectively). The mean CCT decreased from 536.38 ± 24.73 to 533.18 ± 27.25 µm (p=0.002), and the mean CV decreased from 57.52 ± 3.15 to 55.68 ± 3.55 mm³ (p<0.001) after HD. There were no significant changes in ACD, AQD, ACV, ACA, or the keratometric values (p>0.05 for all values). There were no significant correlations between the ocular and systemic parameters (p>0.05 for all correlations). Conclusions: Uncorrected IOP, corrected IOP, CCT, and CV values decreased after HD, whereas the anterior chamber morphometry values remained similar between the measurements performed before and after HD.

RESUMO Objetivo: Avaliar os efeitos da hemodiálise (HD) na morfometria da córnea e da câmara anterior e da pressão intraocular (PIO) em pacientes com doença renal terminal. Métodos: Cinquenta olhos direitos foram examinados 30 minutos antes e após hemodiálise. A pressão intraocular foi medida com um tonômetro de aplanação de Goldmann, e a fórmula de Ehlers foi utilizada para calcular os valores de pressão in traocular corrigidos. Mediram-se a espessura corneana central (CCT), o volume corneano (CV), os valores ceratométricos, a profundidade da câmara anterior (ACD), a profundidade aquosa (AQD), o volume da câmara anterior (ACV) e o ângulo da câmara anterior (ACA) nos quadrantes nasais e temporais com um sistema de análise de segmento Sirius anterior. Os níveis de nitrogênio ureico no sangue (BUN), peso corporal e pressão arterial sistólica e diastólica também foram medidos antes e após a HD. Resultados: A média de idade foi de 60,80 ± 13,38 (35-80) anos. Os valores médios não corrigidos e corrigidos da pressão intraocular diminuíram de 18,06 ± 3,91 e 18,31 ± 4,83 mmHg para 16,94 ± 3,87 e 16,95 ± 4,74 mmHg após hemodiálise (p=0,011 e p=0,003, respectivamente). A espessura corneana central média diminuiu de 536,38 ± 24,73 para 533,18 ± 27,25 µm (p=0,002), e o volume corneano médio diminuiu de 57,52 ± 3,15 para 55,68 ± 3,55 mm³ (p<0,001) após hemodiálise. Não houve alteração significativa nos valores de profundidade da câmara anterior, profundidade aquosa, volume da câmara anterior, ângulo da câmara anterior e ceratométricos (p>0,05 para todos os valores). Não houve correlação significativa entre os parâmetros oculares e sistêmicos (p>0,05 para todas as correlações). Conclusão: A pressão intraocular não corrigida, a pressão intraocular corrigida, a espessura corneana central e os valores de volume corneano diminuíram após hemodiálise, enquanto os valores de morfometria da câmara anterior foram semelhantes entre as medidas realizadas antes e após a hemodiálise.

Interaction of Gender and Hepatitis C in Risk of Chronic Renal Failure After Liver Transplantation

ABSTRACT Background. Chronic renal failure (CRF) is a significant cause of morbidity and mortality in post-liver transplantation (LT) recipients. The risk factors associated with the development of renal dysfunction are not clearly elucidated. Objectives. To examine the risk factors in the development of CRF in these patients. Material and methods. Retrospective case-cohort of liver transplant patients without baseline kidney dysfunction who developed chronic renal failure during their follow-up. Results. Of 370 patients, 254 met the inclusion criteria. 30% (76) of these patients had CRF of which 57% (43) were male. Age, estimated glomerular filtration rate (eGFR) at discharge, and HCV infection were found to be risk factors for CRF post-LT. The odds ratio of developing CRF was 1.4 (0.6-3.3) in males with HCV, 1.6 (0.7-3.9) in females without HCV and 4.4 (1.5-13.2) among females with HCV when compared to men without HCV. Conclusions. In this cohort of LT receipients of a major Canadian city, age, eGFR, and HCV infection were risk factors for CRF. Female gender and HCV increased this odds by a factor of more than 4.

Ankle-Brachial Index as a Predictor of Mortality in Hemodialysis: A 5-Year Cohort Study / Índice Tornozelo-Braquial Como Preditor de Mortalidade em Hemodiálise: Um Estudo de Coorte de 5 Anos

Abstract Background: Abnormal ankle-brachial index (ABI) has been found to be a strong predictor of mortality in some hemodialysis populations in studies with relatively short periods of follow-up, lower than 2 years. Objective: This study aimed to assess the predictive value of abnormal ABI as a risk factor for death among patients on maintenance hemodialysis after a 5-year follow-up. Methods: A total of 478 patients on hemodialysis for at least 12 months were included in the study. ABI measurement was performed using a mercury column sphygmomanometer and portable Doppler. Patients were divided into 3 groups according to ABI (low: <0.9; normal: 0.9 to 1.3; and high: >1.3) and followed for a 60-month period. Results: The prevalence rates of low, normal and high ABI were 26.8%, 64.6% and 8.6%, respectively. The 5-year survival rate was lower in the groups with low ABI (44.1%, P<0.0001) and high ABI (60.8%, P= 0.025) than in the group with normal ABI (71.7%). Cox regression was used to evaluate the association between ABI and mortality, adjusting for potential confounders. Using normal ABI as reference, a low, but not a high ABI was found to be an independent risk factor for all-cause mortality (HR2.57; 95% CI, 1.84-3.57 and HR 1.62; 95% CI, 0.93-2.83, respectively). Conclusions: long-term survival rates of patients with either low or high ABI were lower than the one from those with normal ABI. However, after adjustment for potential confounders, only low ABI persisted as an independent risk factor for all-cause mortality among hemodialysis patients.

Resumo Fundamento: O índice tornozelo-braquial (ITB) foi apontado como um forte preditor de mortalidade em algumas populações de pacientes em hemodiálise em estudos com períodos relativamente curtos de acompanhamento (inferior a 2 anos). Objetivo: Avaliar o valor preditivo do ITB anormal como um fator de risco de morte em pacientes em hemodiálise após 5 anos de acompanhamento. Métodos: Um total de 478 pacientes em hemodiálise por pelo menos 12 meses foram incluídos no estudo. A medida de ITB foi realizada usando-se esfigmomanômetro com coluna de mercúrio e Doppler portátil. Os pacientes foram divididos em 3 grupos de acordo com o ITB (baixo: < 0,9; normal: 0,9 - 1,3; e alto: >1,3), e acompanhados por um período de 60 meses. Resultados: As prevalências de ITB baixo, normal e alto foram 26,8%, 64,6% e 8,6%, respectivamente. A taxa de sobrevida de 5 anos foi menor nos grupos com ITB baixo (44,1%, p <0,0001) e ITB alto (60,8%, p = 0,025) que no grupo com ITB normal (71,7%). A regressão de Cox foi usada para avaliar a associação entre ITB e mortalidade, ajustando para potenciais fatores de confusão. Usando o ITB normal como referência, um baixo ITB, mas não um alto ITB foi identificado como um fator de risco independente para mortalidade por todas as causas (HR2,57; IC95%, 1,84-3,57 e HR 1,62; 95% CI, 0,93-2,83, respectivamente). Conclusões: as taxas de sobrevida em longo prazo de pacientes com um ITB baixo ou alto foram menores que de pacientes com um ITB normal. No entanto, após ajuste por fatores de confusão, somente o ITB baixo manteve-se como um fator de risco independente para mortalidade por todas as causas entre pacientes em hemodiálise.

The Impact of Diabetes Mellitus on Vascular Biomarkers in Patients with End-Stage Renal Disease

PURPOSE: Diabetes mellitus (DM) is the most common cause of end-stage renal disease (ESRD) and an important risk factor for cardiovascular (CV) disease. We investigated the impact of DM on subclinical CV damage by comprehensive screening protocol in ESRD patients. MATERIALS AND METHODS: Echocardiography, coronary computed tomography angiogram, 24-h ambulatory blood pressure monitoring, and central blood pressure with pulse wave velocity (PWV) were performed in 91 ESRD patients from the Cardiovascular and Metabolic disease Etiology Research Center-HIgh risk cohort. RESULTS: The DM group (n=38) had higher systolic blood pressure than the non-DM group (n=53), however, other clinical CV risk factors were not different between two groups. Central aortic systolic pressure (148.7±29.8 mm Hg vs. 133.7±27.0 mm Hg, p= 0.014), PWV (12.1±2.7 m/s vs. 9.4±2.1 m/s, p<0.001), and early mitral inflow to early mitral annulus velocity (16.7±6.4 vs. 13.7±5.9, p=0.026) were higher in the DM group. Although the prevalence of coronary artery disease (CAD) was not different between the DM and the non-DM group (95% vs. 84.4%, p=0.471), the severity of CAD was higher in the DM group (p=0.01). In multivariate regression analysis, DM was an independent determinant for central systolic pressure (p=0.011), PWV (p<0.001) and the prevalence of CAD (p=0.046). CONCLUSION: Diabetic ESRD patients have higher central systolic pressure and more advanced arteriosclerosis than the non-DM control group. These findings suggest that screening for subclinical CV damage may be helpful for diabetic ESRD patients.

Analysis of the Use of Extracorporeal Circulation on the In-Hospital Outcomes of Dialytic Patients Who Underwent Myocardial Revascularization Surgery / Análise do Uso da Circulação Extracorpórea na Evolução Intra-Hospitalar de Pacientes Dialíticos Submetidos à Revascularização Cirúrgica do Miocárdio

Abstract Background: Myocardial revascularization surgery is the best treatment for dyalitic patients with multivessel coronary disease. However, the procedure still has high morbidity and mortality. The use of extracorporeal circulation (ECC) can have a negative impact on the in-hospital outcomes of these patients. Objectives: To evaluate the differences between the techniques with ECC and without ECC during the in-hospital course of dialytic patients who underwent surgical myocardial revascularization. Methods: Unicentric study on 102 consecutive, unselected dialytic patients, who underwent myocardial revascularization surgery in a tertiary university hospital from 2007 to 2014. Results: Sixty-three patients underwent surgery with ECC and 39 without ECC. A high prevalence of cardiovascular risk factors was found in both groups, without statistically significant difference between them. The group "without ECC" had greater number of revascularizations (2.4 vs. 1.7; p <0.0001) and increased need for blood components (77.7% vs. 25.6%; p <0.0001) and inotropic support (82.5% vs 35.8%; p <0.0001). In the postoperative course, the group "without ECC" required less vasoactive drugs, (61.5% vs. 82.5%; p = 0.0340) and shorter time of mechanical ventilation (13.0 hours vs. 36,3 hours, p = 0.0217), had higher extubation rates in the operating room (58.9% vs. 23.8%, p = 0.0006), lower infection rates (7.6% vs. 28.5%; p = 0.0120), and shorter ICU stay (5.2 days vs. 8.1 days; p = 0.0054) as compared with the group with ECC surgery. No difference in mortality was found between the groups. Conclusion: Myocardial revascularization with ECC in patients on dialysis resulted in higher morbidity in the perioperative period in comparison with the procedure without ECC, with no difference in mortality though.

Resumo Fundamento: A revascularização cirúrgica do miocárdio é o melhor tratamento para o paciente dialítico com doença coronariana multiarterial. Contudo, o procedimento ainda apresenta elevada morbimortalidade. O uso da circulação extracorpórea (CEC) pode impactar de maneira negativa na evolução intra-hospitalar desses pacientes. Objetivos: Avaliar a diferença entre as técnicas com ou sem CEC na evolução intra-hospitalar de pacientes dialíticos submetidos a cirurgia de revascularização do miocárdio. Métodos: Estudo unicêntrico de 102 pacientes dialíticos consecutivos e não selecionados, submetidos à revascularização cirúrgica do miocárdio em um hospital terciário universitário no período de 2007 a 2014. Resultados: 63 pacientes foram operados com CEC e 39 sem o uso de CEC. Foi observada alta prevalência de fatores de risco cardiovascular em ambos grupos, porém sem diferença estatisticamente significante entre eles. O grupo "com CEC" apresentou maior número de coronárias revascularizadas (2,4 vs 1,7; p <0,0001), maior necessidade de hemocomponentes (77,7% vs 25,6%; p <0,0001) e apoio inotrópico (82,5% vs 35,8%; p <0,0001). Na evolução pós-operatória, o grupo "sem CEC" apresentou menor necessidade de drogas vasoativas (61,5% vs 82,5%; p = 0,0340), maior taxa de extubação em sala cirúrgica (58,9% vs 23,8%, p = 0,0006), menor tempo de ventilação mecânica (13,0 horas vs 36,3 horas, p = 0,0217), menor taxa de infecções (7,6% vs 28,5%; p = 0,0120) e menor tempo de internação em UTI (5,2 dias vs 8,1 dias; p = 0,0054) em comparação ao grupo "com CEC". Não houve diferença de mortalidade entre os grupos. Conclusão: O uso da CEC na revascularização do miocárdio em pacientes dialíticos resultou em maior morbidade no período perioperatório em comparação ao procedimento realizado sem CEC, contudo, sem diferença de mortalidade.

Characterization of an experimental model of progressive renal disease in rats

ABSTRACT PURPOSE: To characterize an experimental model of progressive renal disease induced by different degrees of nephrectomy in rats. METHODS: Eighty male Wistar rats were divided into four experimental groups (n=20/group): sham surgery (control group), progressive degrees of nephrectomy leading to mild uremia (group 1), moderate uremia (group 2) and severe uremia (group 3). Ten animals of each group were followed for two or four weeks. At the end, blood and 24-hour urine samples were collected to determine renal function parameters. Urine output and water and food intake were daily monitored. RESULTS: In rats of group 1, serum levels of creatinine and urea and microalbuminuria were increased, while reduced creatinine clearance (p<0.05, compared with control group), without changing blood pressure. Animals of group 2 had more accentuated alterations: increases in urinary output, blood pressure, serum concentrations of urea, creatinine, sodium, potassium, and in microalbuminuria, and reduction of creatinine clearance (p<0.05). Group 3 exhibited even more increased serum concentrations of urea, creatinine, sodium and potassium, blood pressure and microalbuminuria, and decreased creatinine clearance (p<0.05) in comparison with control group and unilateral nephrectomy. CONCLUSION: Progressive nephrectomy in rats seems to be useful to study the physiopathology of chronic kidney disease and its mechanisms of progression.

Impact of neuromuscular electrical stimulation on functional capacity of patients with chronic kidney disease on hemodialysis / Impacto da estimulação elétrica neuromuscular na capacidade funcional de pacientes com doença renal crônica submetidos à hemodiálise

Abstract Introduction: Literature shows that patients undergoing hemodialysis present poor physical conditioning and low tolerance to exercise. They may also suffer from respiratory dysfunctions. The purpose of this study was to evaluate the effects of neuromuscular electrical stimulation on pulmonary function and functional capacity of patients with chronic kidney disease on hemodialysis. Methods: Forty adult patients with chronic kidney disease on hemodialysis were prospectively studied and randomized into two groups (control n = 20 and treatment n = 20). The treatment group underwent bilateral femoral quadriceps muscles electrical stimulation for 30 minutes during hemodialysis, three times per week, for two months. The patients were evaluated by pulmonary function test, maximum respiratory pressures, maximum one-repetition test, and six-minute walk test (6MWT), before and after the treatment protocol. Results: The treatment group presented increased maximum inspiratory (MIP) (p = 0.02) and expiratory pressures (MEP) (p < 0.0001), muscular strength in maximum one-repetition test (p < 0.001), and distance covered in the 6MWT (p = 0.03), and decreased systolic blood pressure (p < 0.001) and respiratory frequency (p < 0.001) when compared with the control group. Conclusion: Electrical neuromuscular stimulation had a positive impact on pulmonary function and functional capacity, leading to better physical performance in patients on hemodialysis.

Resumo Introdução: Pacientes submetidos à hemodiálise apresentam baixo condicionamento físico além de serem acometidos por disfunções respiratórias. Objetivamos avaliar os efeitos da estimulação elétrica neuromuscular na função pulmonar e capacidade funcional de pacientes com doença renal crônica em hemodiálise. Método: 40 adultos com doença renal crônica em hemodiálise foram estudados prospectivamente e randomizados em dois grupos (controle n = 20 e tratamento n = 20). O grupo tratamento realizou protocolo com estimulação elétrica neuromuscular em quadríceps femoral por 30 minutos durante a hemodiálise, três vezes por semana, durante dois meses. Todos pacientes realizaram espirometria, pressões respiratórias máximas, teste de uma repetição máxima e teste da caminhada dos seis minutos (TC6), antes e após o período de acompanhamento. Resultados: O grupo tratamento apresentou aumento da pressão inspiratória máxima com p = 0,02 na comparação entre grupos e p < 0,001 para a pressão máxima expiratória. O teste de uma repetição máxima e a distância percorrida no TC6 apresentaram-se maiores após o protocolo no grupo de tratamento com p < 0,001 e 0,03 respectivamente. Houve diminuição da pressão arterial sistólica (p < 0,001) e frequência respiratória (p < 0,001) após a estimulação elétrica quando comparado ao grupo controle. Conclusão: A estimulação elétrica neuromuscular teve impacto positivo sobre a função pulmonar e a capacidade funcional levando ao melhor desempenho físico em pacientes em hemodiálise.

Evaluation of choroidal and retinal thickness measurements in adult hemodialysis patients using spectral-domain optical coherence tomography / Avaliação de medidas de coroide e espessura da retina em pacientes em hemodiálise adultos usando tomografia de coerência óptica de domínio espectral

ABSTRACT Purpose: To assess the effect of hemodialysis on retinal and choroidal thicknesses using spectral-domain optical coherence tomography (SD-OCT). Methods: In this prospective interventional study, 25 hemodialysis patients (17 male, 8 female) were enrolled. All participants underwent high-speed, high-resolution SD-OCT (λ=840 mm; 26.000 A-scans/s; 5 µm resolution) before and after hemodialysis. Choroidal thickness was measured perpendicularly from the outer edge of the retinal pigment epithelium to the choroid-sclera boundary at the fovea and at five additional points: 500 µm and 1000 µm nasal to the fovea and 500 µm, 1000 µm, and 1500 µm temporal to the fovea. Two masked physicians performed the measurements. Choroidal and retinal thicknesses before and after hemodialysis were compared. Results: The median choroidal thicknesses before and after hemodialysis were 182 µm (range, 103-374 µm) and 161 µm (range, 90-353 µm), respectively (P<0.001). The median retinal thicknesses were 246 µm (range, 179-296 µm) before and 248 µm (range, 141-299 µm) after hemodialysis (P>0.05). Systolic arterial pressure, diastolic arterial pressure, mean arterial pressure, heart rate, and ocular perfusion pressure significantly decreased after hemodialysis (P<0.001). Intraocular pressure did not vary significantly (P=0.540). Conclusion: Hemodialysis seems to cause a significant decrease in choroidal thickness, whereas it has no effect on retinal thickness. This significant decrease in choroidal thickness might be due to the extensive fluid absorption in hemodialysis, which could result in decreased ocular blood flow.

RESUMO Objetivo: Avaliar o efeito da hemodiálise (HD) na espessura da retina (RT) e na espessura da coroide (CT) usando tomografia de coerência óptica de domínio espectral (SD-OCT). Método: Neste estudo prospectivo intervencionista foram incluídos 25 pacientes em HD (17 homens e 8 mulheres). Todos os participantes foram submetidos a SD-OCT com dispositivo de alta resolução (λ=840 mm; 26.000 A-scans/seg e resolução de 5 µm), antes e após HD. A CT foi medida perpendicularmente a partir da borda externa do epitélio pigmentar da retina até o limite coroide-esclera na fóvea e em mais de 5 pontos localizados 500 µm nasal à fóvea, 1.000 µm nasal à fóvea; 500 µm temporal à fóvea, 1.000 µm temporal à fóvea, e 1.500 µm temporal à fóvea. Dois médicos realizaram as medidas sem o conhecimento do diagnóstico. Os dados da CT e RT, antes e após a HD foram comparados. Resultados: As CTs medianas antes e após a HD foram 182 µm (variação de 103-374 µm) e 161 µm (variação de 90-353 µm), respectivamente (p<0,001). A RT foi 246 µm (variação de 179-296 µm) antes e 248 µm (variação de 141-299 µm) após a HD (p>0,05). A pressão arterial sistólica, pressão arterial diastólica, as médias de pressão arterial média, frequência cardíaca e pressão de perfusão ocular diminuíram significativamente após HD (p<0,001). A pressão intraocular não alterou significativamente (p=0,540). Conclusão: A HD parece causar uma redução significativa da CT, e não ter efeito sobre a RT. Esta redução significativa da CT pode ser devida à grande absorção de fluido durante a HD, o que pode resultar numa diminuição do fluxo sanguíneo ocular.

The Impact of Hemodialysis and Arteriovenous Access Flow on Extracranial Hemodynamic Changes in End-Stage Renal Disease Patients

In this study, we characterized cerebral blood flow changes by assessment of blood flow parameters in neck arteries using carotid duplex ultrasonography and predictive factors for these hemodynamic changes. Hemodynamic variables were measured before and during hemodialysis in 81 patients with an arteriovenous access in their arm. Hemodialysis produced significant lowering in peak systolic velocity and flow volume of neck arteries and calculated total cerebral blood flow (1,221.9 ± 344.9 [before hemodialysis] vs. 1,085.8 ± 319.2 [during hemodialysis], P < 0.001). Effects were greater in vessels on the same side as the arteriovenous access and these changes were influenced by arteriovenous access flow during hemodialysis, both in the CCA (r = -0.277, P = 0.015) and the VA (r = -0.239, P = 0.034). The change of total cerebral blood flow during hemodialysis was independently related with age, presence of diabetes, and systemic blood pressure.

The Impact of Hemodialysis and Arteriovenous Access Flow on Extracranial Hemodynamic Changes in End-Stage Renal Disease Patients

In this study, we characterized cerebral blood flow changes by assessment of blood flow parameters in neck arteries using carotid duplex ultrasonography and predictive factors for these hemodynamic changes. Hemodynamic variables were measured before and during hemodialysis in 81 patients with an arteriovenous access in their arm. Hemodialysis produced significant lowering in peak systolic velocity and flow volume of neck arteries and calculated total cerebral blood flow (1,221.9 ± 344.9 [before hemodialysis] vs. 1,085.8 ± 319.2 [during hemodialysis], P < 0.001). Effects were greater in vessels on the same side as the arteriovenous access and these changes were influenced by arteriovenous access flow during hemodialysis, both in the CCA (r = -0.277, P = 0.015) and the VA (r = -0.239, P = 0.034). The change of total cerebral blood flow during hemodialysis was independently related with age, presence of diabetes, and systemic blood pressure.