Effect of cholecalciferol on vitamin D-regulatory proteins in monocytes and on inflammatory markers in dialysis patients: A randomized controlled trial.

BACKGROUND & AIMS: Hypovitaminosis D and inflammation are highly prevalent among patients undergoing dialysis, and the association of both conditions with worse survival has been well recognized. Although a potential role for vitamin D in the immune system has been suggested, the effect of the treatment of hypovitaminosis D on the modulation of the inflammatory response remains unclear. The aim of this study was to investigate the effect of the restoration of the vitamin D status on the expression of vitamin D-regulatory proteins in monocytes and on circulating inflammatory markers in dialysis patients. METHODS: In this randomized double-blind placebo-controlled 12-week trial, 38 patients on dialysis with serum 25-hydroxyvitamin D [25(OH)D] <20 ng/mL were randomized either to the cholecalciferol group (n = 20; 50,000 IU of cholecalciferol twice weekly) or to the control group (n = 18; 50 drops of a placebo solution twice weekly). The expression of vitamin D receptor (VDR), CYP27B1, CYP24A1 and interleukin-6 (IL-6) in monocytes was determined by flow cytometry. Serum concentrations of 25(OH)D, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and C-reactive protein (CRP) were measured. The trial is registered at ClinicalTrials.gov #NCT01974245. RESULTS: After 12 weeks, the serum 25(OH)D increased from 14.3 ± 4.7 ng/mL to 43.1 ± 11.0 ng/mL (p < 0.05) in the cholecalciferol group and did not change in the control group (13.9 ± 4.2 ng/mL to 13.5 ± 4.3 ng/mL; p = 0.56). In monocytes, while CYP27B1 expression and VDR expression increased in the cholecalciferol group (p < 0.05), CYP27B1 expression did not change, and VDR expression decreased in the control group (p < 0.05). There were no changes in IL-6 and CYP24A1 expression in both groups. Serum concentration of IL-6 and CRP decreased from 8.1 ± 6.6 pg/mL to 4.6 ± 4.1 pg/mL (p < 0.05) and from 0.50 (0.10-1.27) mg/dL to 0.28 (0.09-0.62) mg/dL (p < 0.05), respectively only in the cholecalciferol group. Assessed overtime, the treatment group differences in 25(OH) D, PTH, CRP and IL-6, CYP27B1 and VDR remained significant. CONCLUSIONS: Restoration of vitamin D status of patients undergoing dialysis promoted upregulation of CYP27B1 and VDR expression in monocytes and a decrease in circulating inflammatory markers.

Impacto da sessão de hemodiálise na força de preensão manual / Impact of hemodialysis session on handgrip strength

Resumo Introdução: A força de preensão manual (FPM) é um método simples, confiável e com bom valor preditivo para avaliar a função muscular de pacientes submetidos à hemodiálise (HD). Porém, ainda não existe um consenso a respeito do momento mais apropriado para a aferição da medida, já que o desempenho da FPM pode ser influenciado pelas flutuações hidroeletrolíticas e de pressão arterial que acometem esses pacientes. Objetivo: Investigar o impacto da sessão de diálise sobre a FPM em pacientes submetidos à HD. Métodos: Trata-se de um estudo transversal com 156 pacientes [57,7% homens, idade mediana de 56,5 (42-67) anos, 28,8% diabéticos, IMC médio de 24,75 ± 4,5 kg/m2 e tempo em HD de 38 (19,25-72,75) meses]. Foram realizadas aferições da FPM com um dinamômetro nos minutos iniciais e ao término da sessão de HD. Os valores obtidos foram comparados com um padrão de referência nacional. Dados clínicos, demográficos e laboratoriais foram coletados do prontuário médico. Resultados: Foi observada uma redução significante da FPM após a sessão de HD (28,6 ± 11,4 kg para 27,7 ± 11,7 kg; p < 0,01). A prevalência de pacientes com FPM abaixo do percentil 30 aumentou de 44,9% para 55,1% (p < 0,01). A redução da pressão arterial durante a diálise foi o único fator que se associou com a redução da FPM. Conclusão: Os achados mostram que o processo de HD influencia negativamente a FPM.

Abstract Introduction: Handgrip strength (HGS) is a simple and reliable method with a good predictive clinical value for assessing muscle function of patients undergoing hemodialysis (HD). However, there is no consensus regarding the appropriate moment for performing the HGS measurement since the performance of the HGS can be influenced by fluid, electrolyte and blood pressure changes that affect patients on HD. Objective: To investigate the impact of the dialysis session on the HGS in patients undergoing HD. Methods: This is a cross-sectional study with 156 patients [57.7% male, median age of 56.5 (42-67) years old, 28.8% diabetes, mean BMI of 24.75 ± 4.5 kg/m2 and HD vintage of 38 (19.25 to 72.75) months]. Measures of HGS were performed with a dynamometer during the initial minutes of the HD session and at the end of the session. The values obtained were compared with a national standard reference. Clinical, demographic and laboratory data were collected from medical records. Results: A significant reduction of HGS was observed after the HD session (28.6 ± 11.4 kg to 27.7 ± 11.7 kg; p < 0.01). The prevalence of patients with HGS below the 30th percentile increased from 44.9% to 55.1% (p < 0.01). The decrease in blood pressure during dialysis was the only factor associated with the reduction of HGS. Conclusion: These findings show that the HD procedure affects negatively the HGS.

Pericardial fat is associated with coronary artery calcification in non-dialysis dependent chronic kidney disease patients.

Pericardial fat (PF) a component of visceral adipose tissue has been consistently related to coronary atherosclerosis in the general population. This study evaluated the association between PF and coronary artery calcification (CAC) in non-dialysis dependent chronic kidney disease (CKD) patients. This is a post-hoc cross sectional analysis of the baseline of a prospective cohort of 117 outward CKD patients without manifest coronary artery disease (age, 56.9 ± 11.0 years, 64.1% males, 95.1% hypertensives, 25.2% diabetics, 15.5% ever smokers, CKD stage 2 to 5 with estimated glomerular filtration rate 36.8 ± 18.1 ml/min). CAC scores, PF volume and abdominal visceral fat (AVF) areas were measured by computed tomography. The association of PF as a continuous variable with the presence of CAC was analyzed by multivariate logistic regression. CAC (calcium score > 0) was present in 59.2% patients. Those presenting CAC were on average 10 years older, had a higher proportion of male gender (78.7% vs. 42.9%, p < 0.001), and had higher values of waist circumference (95.9 ± 10.7 vs. 90.2 ± 13.2 cm, p = 0.02), PF volumes (224.8 ± 107.6 vs. 139.1 ± 85.0 cm3, p<0.01) and AVF areas (109.2 ± 81.5 vs. 70.2 ± 62.9 cm2, p = 0.01). In the multivariate analysis, adjusting for age, gender, diabetes, smoking and, left ventricular concentric hypertrophy, PF was significantly associated with the presence of CAC (OR: 1.88 95% CI: 1.03-3.43 per standard deviation). PF remained associated with CAC even with additional adjustments for estimated glomerular filtration rate or serum phosphorus (OR: 1.85 95% CI: 1.00-3.42, p = 0.05). PF is independently associated with CAC in non-dialysis dependent CKD patients.

Subjective global assessment for the diagnosis of protein-energy wasting in nondialysis-dependent chronic kidney disease patients.

OBJECTIVES: Subjective global assessment (SGA) has been demonstrated to be a reliable method for protein-energy wasting (PEW) evaluation in chronic kidney disease (CKD) patients on dialysis. Few data are available on PEW evaluation in nondialysis stages of CKD, and the validity of SGA has been scarcely investigated in this population. Herein, we aimed to evaluate in nondialysis-dependent CKD patients (NDD-CKD): (1) the prevalence of PEW by SGA; (2) the most common abnormalities of the SGA components; and (3) the agreement of SGA with the traditional anthropometric parameters. DESIGN AND SUBJECTS: This is a retrospective cross-sectional study including 922 NDD-CKD patients referred to the renal dietitians in the period of 2001 to 2012. Nutritional status was assessed by 7-point SGA. Body mass index (BMI), midarm circumference, midarm muscle circumference, and triceps skinfold thickness were available from 494 patients. RESULTS: From the 922 patients, 58.6% were men, mean age was 63.8 ± 13.6 years, BMI was 27.7 ± 5.3 kg/m(2). The majority of the patients were in CKD Stages 3 (48.9%) or 4 (40.3%). PEW (SGA ≤5) was present in 11% of the patients and 32% had signs of PEW (SGA 6). In the logistic regression analysis, the presence of comorbidities and worse renal function were independently associated with PEW. Among the SGA components, the most frequent abnormality in patients with PEW was muscle and fat wasting (88.6%). BMI, midarm circumference, midarm muscle circumference, and triceps skinfold thickness were lower across the worse SGA scores, and a moderate to good level of agreement was found between the anthropometric parameters and presence of PEW evaluated by SGA. CONCLUSIONS: The prevalence of PEW was 11% in our unselected cohort of NDD-CKD patients. The physical examination component (muscle/fat wasting) was the most frequent alteration found in those patients. When compared with anthropometric parameters, 7-point SGA has shown to be a valid tool to assess PEW in NDD-CKD population.

Espessura do músculo adutor do polegar como preditor da força de preensão manual nos pacientes em hemodiálise / Adductor pollicis muscle thickness as a predictor of handgrip strength in hemodialysis patients

INTODUÇÃO: A espessura do músculo adutor do polegar (EMAP) tem sido sugerida como um novo marcador de estado nutricional em diversas populações. OBJETIVO: Diante da escassez de dados sobre o uso desse marcador nos pacientes com doença renal crônica, o objetivo deste estudo foi avaliar a EMAP e sua associação com indicadores nutricionais em pacientes em hemodiálise. MÉTODOS: Foram avaliados 73 pacientes em hemodiálise (52,3 ± 17 anos, sem função renal residual). A EMAP foi aferida no braço sem o acesso vascular com o auxílio de um adipômetro. A composição corporal (bioimpedância elétrica), a força de preensão manual (dinamômetro), o estado nutricional (Avaliação Global Subjetiva) e os exames laboratoriais (creatinina, proteína total e albumina) também foram avaliados. RESULTADOS: Indivíduos com valores de EMAP acima da mediana eram em maior proporção negros/pardos, jovens e possuíam maior força de preensão manual. A EMAP correlacionou-se positivamente com a força de preensão manual, albumina sérica e massa celular (%), e negativamente com a idade. Na análise de regressão linear ajustada para sexo, idade e tempo em hemodiálise, a EMAP esteve independentemente associada com a força de preensão manual. CONCLUSÃO: A EMAP foi capaz de predizer a força de preensão manual nos pacientes em hemodiálise, o que sugere a EMAP como um marcador promissor de estado nutricional nessa população.

INTRODUCTION: Recently, the adductor pollicis muscle thickness (APMT) has been suggested as a new nutritional marker in several population. OBJECTIVE: In view of the scarce data regarding the use of this marker in CKD patients, we aimed to evaluate APMT and its association with nutritional parameters in patients on hemodialysis. METHODS: We evaluated 73 hemodialysis patients (52.3 ± 17 years, without residual renal function). The APMT was assessed in the non vascular access arm by means of skinfold caliper. Body composition (bioelectrical impedance), handgrip strength (HGS, dynamometer), nutritional status (subjective global assessment), and laboratory parameters (creatinine, total protein and albumin) were also evaluated. RESULTS: Subjects with APMT values above the median were in greater proportion black/ brown, younger and had higher HGS. The APMT correlated positively with HGS, albumin and body cell mass (%), and negatively with age. In the linear regression analysis adjusted for sex, age and length on hemodialysis, APMT was independently associated with HGS. CONCLUSION: APMT was able to predict HGS in hemodialysis patients, suggesting APMT as a promising nutritional marker in this population.

Variações nos níveis de adiponectina nos pacientes com doença renal crônica: um estudo prospectivo de 12 meses / Variations in adiponectin levels in patients with chronic kidney disease: a prospective study of 12 months

INTRODUÇÃO: As complicações cardiovasculares permanecem como a principal causa de mortalidade nos pacientes portadores de doença renal crônica (DRC). A adiponectina é uma proteína produzida pelo tecido adiposo que apresenta importante propriedade cardioprotetora. O nosso objetivo foi investigar os determinantes dos níveis de adiponectina nos pacientes com DRC. MÉTODOS: Este estudo prospectivo observacional incluiu 98 pacientes [taxa de filtração glomerular (TFG) 36,1+-14,4 ml/min; 56,5+-10,4 anos; 63% homens; 31% diabéticos e índice de massa corporal (IMC) 27,1+-5,2 kg/m²]. A avaliação da adiponectina (teste imunoenzimático), dos parâmetros laboratoriais, do estado nutricional (avaliação global subjetiva), da gordura corporal total (absortometria de raios-x de dupla energia) e da gordura abdominal visceral e subcutânea (tomografia computadorizada) foi realizada no início e após 12 meses. RESULTADOS: A adiponectina correlacionou-se com a TFG (r = -0,45; p < 0,001), a proteinúria (r = 0,21; p = 0,04), o IMC (r = -0,33; p < 0,01) e a gordura visceral (r = -0,49; p < 0,001). Na análise de regressão múltipla, os determinantes das concentrações de adiponectina foram o sexo (feminino β = 3,8; p < 0,01), a idade (β = 0,14; p = 0,03), a TFG (β = -0,15; p < 0,01) e a gordura visceral (β = -0,04; p < 0,001) (R² = 0,41). Após 12 meses, a progressão da DRC foi evidenciada pela diminuição da TFG (-1,6+-6,3 ml/min; p = 0,01) e aumento da proteinúria (0,3+-0,8 g/d; p < 0,01). Houve um aumento da gordura visceral de 97+-73 cm² para 111+-82 cm² (p < 0,001) e concomitante redução dos níveis de adiponectina, de 27,6+-7,5 mg/l para 22,2+-11,6 mg/l (p < 0,001). O peso corporal, o IMC, a gordura corporal total e a gordura abdominal subcutânea não se alteraram neste período. Ajustando pelos fatores associados à adiponectina, observamos que somente o acúmulo de gordura visceral ao longo do tempo determinou a redução nos níveis de adiponectina (β = -0,04; p = 0,025; R² = 0,21). CONCLUSÃO: A idade, o sexo, a função renal e a gordura visceral estiveram independentemente associados com os níveis de adiponectina nos pacientes com DRC na fase não dialítica. No entanto, a mudança da gordura visceral foi o único preditor das variações nos níveis de adiponectina ao longo de 12 meses.

BACKGROUND: Cardiovascular complications remain the main cause of mortality in patients with chronic kidney disease (CKD). Adiponectin is an adipose tissue-derived protein that carries important cardioprotective properties. We aimed at investigating the determinants of adiponectin levels in CKD patients. METHODS: This prospective observational study included 98 CKD patients [glomerular filtration rate (GFR) 36.1+-14.4 ml/min, 56.5+-10.4 y, 63% male, 31% diabetics, and body mass index (BMI) 27.1+-5.2 kg/m²]. Evaluation of adiponectin (imunoenzimatic assay), laboratory parameters, nutritional status (subjective global assessment), total body fat (dual x-ray energy absorptiometry), and visceral and subcutaneous abdominal fat (computed tomography) was performed at baseline and after 12 months. RESULTS: Adiponectin correlated with GFR (r = -0.45; p < 0.001), proteinuria (r = 0.21; p = 0.04), BMI (r = -0.33; p < 0.01), and visceral fat (r = -0.49; p < 0.001). In the linear regression analysis, the determinants of adiponectin levels were sex (female β = 3.8; p < 0.01), age (β = 0.14; p = 0.03), GFR (β = -0.15; p < 0.01) and visceral fat (β = -0.04; p < 0.001) (R² = 0.41). After 12 months, a progression of the disease was evidenced by the reduction of GFR (-1.6+-6.3 ml/min; p = 0.01) and increase of proteinuria (0.3+-0.8 g/d; p < 0.01). An accumulation of visceral fat was observed, from 97+-73 cm² to 111+-82 cm² (p < 0.001), with a concomitant reduction of adiponectin concentration, from 27.6+-7.5 mg/l to 22.2+-11.6 mg/l (p < 0.001). Body weight, BMI, total body fat, and subcutaneous abdominal fat remained unchanged. After adjustments for the baseline determinants of adiponectin, the increase in visceral fat was independently associated with overtime decrease in adiponectin levels (β = -0.04; p = 0.025; R² = 0.21). CONCLUSION: Age, sex, renal function and visceral fat were independently associated with adiponectin levels in nondialyzed CKD patients. However, variation in visceral fat was the only predictor of variation in adiponectin levels over 12 months.

Impact of training at ventilatory threshold on cardiopulmonary and functional capacity in overweight patients with chronic kidney disease / Exercício aeróbico baseado no primeiro limiar ventilatório em pacientes com excesso de peso e doença renal crônica: impacto sobre a capacidade cardiorrespiratória e funcional

INTRODUCTION: Chronic kidney disease (CKD) and obesity are both associated with reduced physical capacity. The potential benefit of aerobic training on physical capacity has been recognized. The exercise intensity can be established using different methods mostly subjective or indirect. Ventilatory threshold (VT) is a direct and objective method that allows prescribing exercise intensity according to individual capacity. OBJECTIVES: To evaluate the impact of aerobic training at VT intensity on cardiopulmonary and functional capacities in CKD patients with excess of body weight. METHODS: Ten CKD patients (eight men, 49.7 ± 10.1 years; BMI 30.4 ± 3.5 kg/m², creatinine clearance 39.4 ± 9.8 mL/min/1.73 m²) underwent training on a treadmill three times per week during 12 weeks. Cardiopulmonary capacity (ergoespirometry), functional capacity and clinical parameters were evaluated. RESULTS: At the end of 12 weeks, VO2PEAK increased by 20%, and the speed at VO2PEAK increased by 16%. The training resulted in improvement in functional capacity tests, such as six-minute walk test (9.2%), two-minute step test (20.3%), arm curl test (16.3%), sit and stand test (35.7%), and time up and go test (15.3%). In addition, a decrease in systolic and diastolic blood pressures was observed despite no change in body weight, sodium intake and antihypertensive medication. CONCLUSION: Aerobic exercise performed at VT intensity improved cardipulmonary and functional capacities of overweight CKD patients. Additional benefit on blood pressure was observed. These results suggest that VT can be effectively applied for prescribing exercise intensity in this particular group of patients.

INTRODUÇÃO: O excesso de peso e a doença renal crônica (DRC) estão associados à baixa capacidade cardiorrespiratória (CR) e funcional (CF). Já foi observado que o treinamento aeróbico (TA) melhora a CR e CF. Métodos indiretos e subjetivos são comumente empregados para a prescrição da intensidade do TA. O limiar ventilatório (LV) é um método direto e objetivo que permite prescrever a intensidade do TA de acordo com a capacidade física do paciente. OBJETIVOS: Avaliar o impacto do TA com base na intensidade do LV sobre a CR e CF de pacientes com excesso de peso e portadores de DRC na fase não dialítica. MÉTODOS: Dez pacientes (oito homens; 49 ± 10,1 anos, IMC 30,4 ± 3,5 kg/m² , depuração de creatinina 39,4 ± 9,8 mL/min/1,73m²) foram submetidos à TA 3 vezes por semana durante 12 semanas. CR (ergoespirometria), CF e parâmetros clínicos foram avaliados. RESULTADOS: O TA promoveu aumento de 20% no consumo pico de O2 (VO2PICO), 16% na velocidade alcançada no VO2PICO e melhora em 9,2% na caminhada de seis minutos, 20,3% na marcha estacionária, 35,7% no sentar e levantar, 16,3% na resistência muscular de membro superior e 15,3% no tempo de ir e voltar. A pressão arterial diminuiu sem modificação nos anti-hipertensivos, no peso ou no consumo de sódio. CONCLUSÃO: Os resultados indicam que o TA baseado na intensidade do LV melhora a CR, CF e pressão arterial de pacientes portadores de DRC com excesso de peso. Isso sugere que o TA baseado na intensidade LV é eficaz e pode ser empregado com segurança nesses pacientes.

Activity-related energy expenditure of patients undergoing hemodialysis.

OBJECTIVES: The aim of this study was to evaluate the activity-related energy expenditure (AEE) of patients undergoing hemodialysis (HD) and to compare it with that of healthy controls. DESIGN: This was a cross-sectional study. SETTING: This was an in-center study conducted at the Dialysis Unit, Nephrology Division, Federal University of São Paulo-Oswaldo Ramos Foundation, Brazil. PATIENTS AND METHODS: AEE was evaluated in 32 patients undergoing HD (20 men, aged: 46.3 ± 12.2 years). A subgroup consisting of 22 patients was pair-matched by gender and age with 22 sedentary, healthy individuals. AEE was measured over a period of 5 days using a portable physical activity monitor. Body fat and lean body mass were assessed by dual energy X-ray absorptiometry and body cell mass by bioelectrical impedance analysis. RESULTS: AEE correlated positively with lean body mass and body cell mass, and negatively with age, body fat, and body mass index. From the multiple regression analysis, it was found that age and lean body mass (r(2) = 0.32) or body cell mass (r(2) = 0.30) were the best among the variables that explained variations in AEE. AEE of HD patients in comparison with healthy controls was found to be lower on dialysis days (234 [9.5 to 1,145] kcal/day vs. 565 [214 to 1,319] kcal/day, median [range]; P < .01) as well as on nondialysis days (369 [89.5 to 1,242] kcal/day vs. 565 [214 to 1,319] kcal/day; P = .02). Total energy expenditure of the HD patients on dialysis days (2,051 ± 289 kcal/day) as well as nondialysis days (2,202 ± 283 kcal/day) was also found to be lower in comparison with controls (2,514 ± 307 kcal/day; P < .01). The average contribution of the AEE toward total energy expenditure in HD patients was 15%, whereas in controls it was 24% (P = .03). CONCLUSION: As compared with sedentary, healthy individuals, AEE was reported to be considerably lower in HD patients.

Gasto energético de repouso em pacientes com doença renal crônica / Resting energy expenditure in patients with chronic kidney disease

O conhecimento do gasto energético de repouso é de fundamental importância na determinação das necessidades energéticas e, conseqüentemente, no estabelecimento das recomendações de energia de um indivíduo. O elevado gasto energético, se não compensado por uma ingestão alimentar suficiente, poderá contribuir para a desnutrição e o maior risco de morbidade e mortalidade. Nos pacientes com doença renal crônica, a uremia per se e o tratamento de diálise estão, freqüentemente, associados a vários distúrbios, como a acidose metabólica, a resistência insulínica, o hiperparatireoidismo secundário e a inflamação, que podem aumentar o catabolismo protéico e, em parte, contribuir para o aumento do gasto energético de repouso. A presente revisão tem como objetivo descrever os estudos sobre o gasto energético de repouso nos pacientes com doença renal crônica e os aspectos que influenciam o gasto energético nesta população.

Knowledge of resting energy expenditure is of paramount importance for the determination of energy requirements and consequently for the establishment of energy recommendations of an individual. Elevated energy expenditure, if not supplied by enough food consumption, may contribute to malnutrition and higher risk of morbidity and mortality. In patients with chronic kidney disease, uremia per se and the dialysis treatment are frequently associated with several disturbances, such as metabolic acidosis, insulin resistance, secondary hyperparathyroidism and inflammation, that might in part contribute to the increase in resting energy expenditure. The present review aims to describe the studies on resting energy expenditure in patients with chronic kidney disease and the factors influencing energy expenditure in this population.

Estimativa de ingestão protéica de pacientes em hemodiálise comparação entre registro alimentar e equivalente protéico deaparecimento de nitrogênio (pna) / Estimation of protein intake of hemodialysis patients comparison between food record and protein equivalent ofnitrogen appearance (pna)

Introdução: A avaliação do consumo alimentar, particularmente da ingestão de proteínas, constitui uma ferramenta importante na prevenção, tratamento emonitoramento da desnutrição nos pacientes em hemodiálise. Para tanto, os métodos mais comumente utilizados na prática clínica são o registro alimentar eo equivalente protéico do aparecimento de nitrogênio (PNA). Objetivo: Avaliar a concordância entre o registro alimentar e o PNA para a estimativa da ingestãoprotéica nos pacientes em hemodiálise. Casuística e Métodos: Foram estudados 39 pacientes (67% homens, 46,8±14,7anos, IMC 23,5±4,6kg/m2) emtratamento hemodialítico. Os critérios de exclusão foram presença de doenças catabólicas, função renal residual e uso de glucocorticóides. O registro alimentarfoi preenchido durante três dias e o PNA foi calculado conforme recomendado pelo NKF-DOQI. Resultados: A ingestão protéica obtida pelo registro alimentarfoi menor que aquela obtida pelo PNA (56,3±23,4 vs 67,9±23,9g/dia, respectivamente; P≤0,001). Os métodos apresentaram uma boa correlação (r=0,54;P<0,001), porém uma grande variabilidade individual foi observada (-51,7 a +28,5g/dia). A ingestão protéica obtida por ambos os métodos correlacionou-sepositivamente com o IMC (registro alimentar: r=0,41 e PNA r=0,80; P<0,05). A diferença entre os métodos (registro alimentar - PNA) correlacionou-senegativamente com o IMC (r=-0,49; P<0,01). A análise por subgrupos de IMC mostrou que o registro alimentar subestimava a ingestão protéica em relação aoPNA apenas nos pacientes com IMC≥25kg/m2. A regressão linear múltipla apontou o IMC≥25kg/m2 como único fator independentemente associado àsvariações entre os métodos. [β =-16,9 (-31,1 a -2,8); P=0,02] Conclusão: O método do registro alimentar exibiu valores menores de proteínas em relação aométodo do PNA nos pacientes em hemodiálise, sendo a condição de sobrepeso/obesidade um importante determinante destas variações.

Introduction: The assessment of food consumption, particularly of protein intake, constitutes an important tool in the prevention, treatment, and monitoringof malnutrition in hemodialysis patients. Food record and protein equivalent of nitrogen appearance (PNA) are the most commonly used methods for suchpurpose in the clinical practice. Aim: To evaluate the agreement between food record and PNA for the assessment of protein intake in hemodialysis patients.Subjects and Methods: Thirty-nine hemodialysis patients (67% male, 46.8 ± 14.7 years old, BMI 23.5 ± 4.6 kg/m2) were studied. The exclusion criteriawere catabolic illnesses, residual renal function and use of glucocorticoids. Food intake was recorded 3 days and PNA was calculated as proposed by theNKF-DOQI. Results: The protein intake assessed by food record was lower than that obtained by PNA (56.3 ± 23.4 vs 67.9 ± 23.9 g/day, respectively;P≤0.001). The methods were well correlated (r=0.54; P<0.001), however, a large individual variability was observed (-51.7 to +28.5 g/day). The protein intakeobtained by both methods correlated positively with BMI (food record: r=0.41 and PNA: r=0.80; P<0.05). The difference between the methods (food record,PNA) correlated negatively with BMI (r=-0.49; P<0.001). The analysis by subgroups of BMI showed that the food record method underestimated proteinintake in relation to PNA only in patients with BMI ≥25kg/m2. The multiple linear regression analysis pointed to BMI ≥25kg/m2 as a factor independentlyassociated with variations between the methods. Conclusion: The food record method showed lower values of protein in comparison with the PNA methodin hemodialysis patients, and overweight/obesity status was an important determinant of these variations.

Impacto de um programa de educação nutricional no controle da hiperfosfatemia de pacientes em hemodiálise / The impact of a nutrition educational program on the control of the hyperphosphatemia in hemodialysis patients

Introdução: O controle do fósforo sérico é um desafio no tratamento de pacientes em hemodiálise. O emprego de estratégias educativas poderia contribuirpara melhorar a adesão destes pacientes ao tratamento. Assim, o objetivo deste estudo foi avaliar o impacto de um programa de educação nutricional sobreo conhecimento a respeito do fósforo e sobre a fosfatemia de pacientes em hemodiálise. Métodos: Foram incluídos 147 pacientes [85homens/62mulheres,idade= 50,5±15,7 anos, tempo em diálise = 32 (1-205) meses] que estavam no programa de hemodiálise durante o período de agosto a dezembro de 2006.O material educacional incluiu um questionário de avaliação de conhecimentos, uma palestra, jogos e livretos educativos. Foram medidas as concentraçõesséricas de fósforo e uréia, e a eficiência da diálise foi avaliada por meio do Kt/V. Resultados: Após a aplicação do programa educacional, houve umaumento da pontuação do questionário de conhecimentos (5,7±1,1 para 6,6±0,7;P<0,01) e uma redução do fósforo sérico (5,5±1,6 para 5,2±1,6mg/dl;P<0,01). A uréia sérica se manteve e o Kt/V aumentou (1,34±0,28 para 1,43±0,31;P<0,01). Quando os pacientes foram divididos de acordo com aconcentração sérica de fósforo do início do programa, foi observado que, no grupo normofosfatêmico (fósforo sérico ³5,5mg/dl, n=81), não houve alteraçõesno fósforo sérico após a aplicação do programa (4,4±0,7 para 4,6±1,6 mg/dl;P=0,12). Já no grupo hiperfosfatêmico (fósforo sérico ³5,5mg/dl, n=66),observou-se uma redução da concentração sérica de fósforo (6,9±1,2 para 5,8±1,6mg/dl;P<0,01), uréia (173±33 para 167±36mg/dl;P=0,02) e um aumentodo Kt/V (1,26±0,28 para 1,38±0,22;P<0,01). A variação do fósforo sérico neste grupo correlacionou-se positivamente com a variação da uréia sérica(r=0,29; P=0,02), mas não com a variação do Kt/V. A redução da concentração sérica de fósforo para valores inferiores a 5,5mg/dl ocorreu em 39,4.

Serum and cellular interleukin-6 in haemodialysis patients: relationship with energy expenditure.

BACKGROUND: Inflammation is a highly prevalent condition among end-stage renal disease (ESRD) patients and it has been implicated with several metabolic derangements. Considering the harmful effect of hypermetabolism on nutritional status and clinical outcomes of ESRD patients, we aimed to investigate the relationship between proinflammatory cytokine interleukin-6 (IL-6) and energy expenditure in this population. METHODS: This cross-sectional study enrolled 80 adult haemodialysis patients for the evaluation of serum IL-6 and energy expenditure. The production of IL-6 by peripheral blood mononuclear cells (PBMCs) (spontaneous and endotoxin-stimulated production) was examined in a subgroup of 30 haemodialysis patients and in 11 healthy control subjects. IL-6 was measured by immunoenzymatic assay. The resting energy expenditure was evaluated by means of indirect calorimetry. Body composition was assessed by bioelectrical impedance analysis and skinfold thicknesses. RESULTS: Serum IL-6 [6.3 (2.2-163.5) pg/ml] correlated positively with age (R = 0.26; P = 0.02) and C-reactive protein (R = 0.31; P < 0.01). Resting energy expenditure correlated positively with lean body mass (R = 0.68; P < 0.001) and BMI (R = 0.44; P < 0.001), and negatively with Kt/V (R = -0.37; P < 0.01). In the multivariate analysis, controlling for age and lean body mass, serum IL-6 was positively associated with resting energy expenditure (n = 80; beta = 2.4; P = 0.01). The production of IL-6 by PBMCs did not reach statistically significant differences between patients and controls [spontaneous production 6541 (96-7739) pg/ml vs 3410 (50-7806) pg/ml, respectively; and stimulated production 6530 (579-7671) pg/ml vs 5304 (1527-7670) pg/ml, respectively]. IL-6 secreted by monocytes showed no association with either serum IL-6 or resting energy expenditure. CONCLUSION: Serum IL-6 was associated with an increase of energy expenditure in haemodialysis patients.

Increased resting energy expenditure in hemodialysis patients with severe hyperparathyroidism.

Several metabolic derangements, including enhanced protein catabolism, have been suggested to be associated with increased circulating parathyroid hormone (PTH) in patients with secondary hyperparathyroidism (HPT). Such conditions, therefore, might lead to an increase in energy expenditure. The present study examined by indirect calorimetry the resting energy expenditure (REE) of 15 hemodialysis patients who have severe HPT (PTH = 1457 +/- 676 pg/ml) and were pair-matched for age and gender to 15 hemodialysis patients with mild to moderate HPT (PTH = 247 +/- 196 pg/ml). Both groups were also pair-matched for age and gender to a group of 15 healthy adult subjects (control). In six patients from the severe HPT group submitted to total parathyroidectomy, REE was determined 6 mo after the surgery. The groups were not different regarding lean body mass (LBM) measured by bioelectric impedance, serum C-reactive protein, and bicarbonate. Thyroid-stimulating hormone was within the normal range in all groups. Nonadjusted REE was significantly higher in the severe HPT group (1674 +/- 337 kcal/d) compared with patients with mild to moderate HPT (1388 +/- 229 kcal/d; P < 0.05). Both groups did not differ from the control group (1468 +/- 323 kcal/d). When adjustment of REE for LBM was performed using the multiple regression analysis, patients with mild to moderate HPT and control subjects had significantly lower REE (-231 and -262 kcal, respectively) than that of the severe HPT group. Considering all patients together, nonadjusted REE correlated directly with LBM (r = 0.61; P < 0.01). PTH correlated strongly with LBM in the severe HPT group (r = -0.82; P < 0.01). In the multiple linear regression analysis, only LBM and PTH were independent determinants of REE (n = 30; R(2) = 0.47). REE decreased significantly in the six patients who were evaluated 6 mo after parathyroidectomy (from 1617 +/- 339 to 1226 +/- 253; P = 0.02). These results demonstrate that hemodialysis patients with severe HPT have increased REE that might be reduced after parathyroidectomy.

Albumina sérica como marcador nutricional de pacientes em hemodiálise / Serum albumin as nutritional marker of hemodialysis patients

A prevalência de desnutrição protéico-energético em pacientes com insuficiência renal crônica submetidos à terapia de hemodiálise é elevada. Dentre os diversos parâmetros disponíveis para a avaliação do estado nutricional, a albumina tem sido o mais comumente utilizado para este fim visto a sua estreita associação com a morbidade e mortalidade nesta população. No entanto, vários fatores como idade, comorbidades, hipervolemia e perdas corpóreas podem influenciar as concentrações séricas de albumina. Além disso, na vigência de inflamação, condição comumente presente neste grupo de pacientes, o metabolismo da albumina pode encontrar-se alterado, influenciando os seus níveis plasmáticos. Sendo assim, esta comunicação tem como objetivo abordar os aspectos gerais da albumina e discutir a sua utilização na avaliação do estado nutricional de pacientes com insuficiência renal crônica submetidos à hemodiálise.

Métodos de avaliação da composição corporal em pacientes submetidos à hemodiálise / Methods of body composition assessment in patients undergoing hemodialysis

A avaliação da composição corporal de pacientes com insuficiência renal crônica em hemodiálise é de suma importância para propiciar uma conduta clínica e nutricional adequada, de forma a contribuir para a redução da elevada taxa de morbidade e mortalidade observada nesta população. No entanto, fatores relacionados à doença tais como anormalidades no estado de hidratação e presença de osteodistrofia renal, podem afetar a validade das técnicas de avaliação da composição corporal de pacientes com insuficiência renal crônica. Apesar dos inúmeros métodos de análise de composição corporal existentes, a maioria apresenta limitações para utilização na prática clínica da população em hemodiálise. Este artigo tem como objetivo revisar os métodos de composição corporal de fácil aplicabilidade na rotina clínica dos pacientes em hemodiálise tais como a somatória de pregas cutâneas, a bioimpedância elétrica e a interactância do infravermelho próximo.