RESUMO
OBJECTIVES: Higher total energy expenditure in free living conditions, regardless of any activity, has been strongly associated with a lower risk of mortality in healthy older adults. Also, a good performance in physical and functional tests is a marker of good functional prognosis. However, it is not yet clear what is the association between total energy expenditure and the performance in physical and functional tests. The objective of this study was to verify the association between the total energy expenditure of older adults measured by doubly labelled water and the performance in functional tests. DESIGN: Cross-sectional study. SETTINGS AND PARTICIPANTS: Fifty-six older people were recruited from health services linked to the participating institutions. MEASUREMENTS: Socio-demographic, anthropometric and clinical characteristics were assessed through the application of a structured questionnaire. Body composition was evaluated by isotopic dilution of deuterium oxide and functional status was assessed by the gait speed test, 6-minute walk test and handgrip strength. Total energy expenditure (GET) was assessed using the doubly labelled water method and the physical activity profile was verified using an activity monitor based on accelerometery. RESULTS: The results showed that the highest total energy expenditure correlated with the best performance in the gait speed tests (r = 0.266; p = 0.047), 6-minute walk test (r = 0.424; p = 0.001) and maximum handgrip strength (r = 0.478; p = 0.000). Multivariate regression analysis in a model adjusted for sex and fat-free mass revealed an association between total energy expenditure and the 6-minute walk test (ß = 1.790; t = 2.080; p = 0.044) and the number of sedentary events ( ß = 6.389; t = 2.147; p = 0.038). CONCLUSION: The results of this study suggest that, in clinical practice, older individuals with lower gait speed, worse performance in the 6-minute walk test and lower handgrip strength, may have lower total energy expenditure, being the stimulus for its increase important for the prevention of possible problems related to low energy expenditure.
Assuntos
Antropometria/métodos , Metabolismo Energético/genética , Água/química , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , MasculinoRESUMO
BACKGROUND: Several studies have shown that liquid and food intake interfere with the evaluation of body composition in adults. However, since there are no reports about this interference in the elderly population, the need to fast for this evaluation may be dispensable. OBJECTIVES: The objective of the present study was to assess the influence of liquid and solid food on the measurement of body composition by bioelectrical impedance analysis (BIA) and by dual energy X-ray absorptiometry (DXA). DESIGN: Forty-one male volunteers aged 62 to 87 years participated in the study. The subjects were submitted to evaluation of body composition by DXA and BIA under fasting conditions and 1 hour after the ingestion of breakfast (500 ml of orange juice and one 50 g bread roll with butter). RESULTS: There was no significant difference in the variables fat-free mass (FFM) or fat mass (FM) between the fasting condition and the evaluation performed 1 hour after the meal as measured by BIA or DXA. There was also no significant difference when the same variables were compared between methods. CONCLUSION: In the present study, the ingestion of 500 ml orange juice and of one bread roll with butter by elderly subjects did not affect the results of the parameters of body composition determined by BIA or DXA. Thus, these exams could be performed without the rigor of fasting, often poorly tolerated by the elderly.
Assuntos
Bebidas/estatística & dados numéricos , Composição Corporal/fisiologia , Ingestão de Líquidos/fisiologia , Ingestão de Alimentos/fisiologia , Avaliação Geriátrica/estatística & dados numéricos , Absorciometria de Fóton/métodos , Idoso , Idoso de 80 Anos ou mais , Pão , Manteiga , Citrus sinensis , Estudos Transversais , Impedância Elétrica , Jejum/fisiologia , Avaliação Geriátrica/métodos , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Anthropometric parameters are closely associated with the pathophysiology of frailty and with clinic and functional parameters assessed for its diagnosis. OBJECTIVE: To evaluate the possible association of the nutritional status of older people as assessed by Body Mass Index (BMI) and functional disability, self-reported chronic diseases and frailty, comparing the use of two different classifications of BMI. DESIGN: Cross-sectional study. SETTING: The sample was selected among community-dwelling older people from the city of Ribeirão Preto/ Brazil. PARTICIPANTS: 326 independent older people (mean age 73.8±6.4 years) who participated in the FIBRA (Frailty in Brazilian Older People) study. MEASUREMENTS: Weight and height were collected for BMI analysis and frailty criteria were applied according to Fried et al. Participants were also evaluated for self-reported activities of daily living (Katz Index and Lawton and Brody Scale), and the presence of chronic diseases. RESULTS: The prevalence of frailty was 12.3%. Regardless of the classification of BMI applied, most of the sample was classified as overweight (50.9% and 39.3% in the Lipschitz and WHO classifications, respectively). For both classifications, low weight was the only BMI classification associated with frailty status (OR Lipschitz: 4.12(1.53-11.14); OR WHO: 6.21 (1.26-30.58). Comorbidities and dependence in activities of daily living (ADLs) were associated with BMI ≥ 30kg.m2. CONCLUSION: Regardless of the classification adopted, low weight is associated with frailty. However, when the WHO stratification is employed, high BMI is also associated to increased functional disability and the presence of comorbidities, coexisting factors of frailty.
Assuntos
Índice de Massa Corporal , Avaliação Geriátrica , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Antropometria/métodos , Brasil/epidemiologia , Comorbidade , Pessoas com Deficiência/estatística & dados numéricos , Feminino , Idoso Fragilizado/estatística & dados numéricos , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Avaliação Geriátrica/classificação , Avaliação Geriátrica/métodos , Humanos , Vida Independente/estatística & dados numéricos , Masculino , Estado Nutricional , Prevalência , Estatística como AssuntoRESUMO
OBJECTIVE: To evaluate whether oral supplementation with arginine affects the humoral and innate immune response after vaccination against Streptococcus pneumoniae in a group of people aged 60 y and older, free-living in the community. DESIGN: A randomized controlled trial with one supplemented group and one control group. SETTING: Older persons living in the community. SUBJECTS: A total of 29 adults aged 60 y and older. INTERVENTIONS: The older people were randomized into two groups, one with arginine supplementation (15 g/day) for 4 weeks after pneumococcal vaccine. The control group received only the vaccine. Anthropometric measurements and immune system function parameters: neutrophil chemotaxis and phagocytosis, natural killer cell activity, determination of serum pneumococcal polysaccharide antibodies and serum C3 and C4. RESULTS: Neutrophil phagocytosis and the serum concentration of complement (C3 and C4) did not differ between groups. IgG antibodies against pneumococcal polysaccharide serotypes 1, 5 and 6B increased in both groups. The following parameters increased in the arginine-supplemented group compared to the nonsupplemented group: neutrophil chemotaxis (34 vs 19 units of migration, P = 0.002), natural killer cell cytotoxicity (23.3 vs 13.4 10 M/Ul 40%, P = 0.011) and IgG against antigen 5 (12.3 vs 6.2 mug/ml, P = 0.044). CONCLUSIONS: This study suggests that, after the pneumococcal vaccine, the intake of arginine increased neutrophil chemotaxis, natural killer cytotoxicity and serum concentration of IgG against antigen 5 in older people. These results suggest that arginine supplementation may enhance the immune response elicited by the pneumococcal vaccine in older people. SPONSORSHIP: Supported in part by CAPES and FAEPA.
Assuntos
Anticorpos Antibacterianos/imunologia , Formação de Anticorpos/efeitos dos fármacos , Arginina/farmacologia , Imunidade Inata/efeitos dos fármacos , Vacinas Pneumocócicas/imunologia , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antibacterianos/sangue , Formação de Anticorpos/fisiologia , Arginina/administração & dosagem , Quimiotaxia/efeitos dos fármacos , Complemento C3/imunologia , Complemento C4/imunologia , Suplementos Nutricionais , Feminino , Humanos , Imunidade Inata/fisiologia , Imunoglobulina G/sangue , Células Matadoras Naturais/efeitos dos fármacos , Masculino , Pessoa de Meia-IdadeRESUMO
Recent studies have suggested a short-term impairment in the regulation of food intake in older adults, but further studies are needed to determine if a longer-term impairment exists and to identify underlying causes. Changes in body weight and composition were measured over a 6-week underfeeding study and a 6-month follow-up period in healthy young (n = 23) and older (OLD, n = 18) men and women. The young adults were either normal weight (YNW, n = 12) or overweight (YOW, n = 11). Energy intakes during underfeeding were 896 +/- 18 (SEM) kcal less than weight-maintenance energy requirements determined prior to underfeeding. In addition, changes in perceived hunger during underfeeding were monitored in a subgroup (n = 19). OLD and YOW subjects lost significantly more weight during underfeeding than did YNW subjects (p = .025 and .000, respectively), and they did not gain back significant weight in the 6-month follow-up. In addition, OLD subjects reported a significantly lower frequency of hunger during underfeeding (p = .05). There was no significant difference among groups in the relationship between weight lost and fat-free mass lost. Healthy OLD adults have an impaired ability to regulate food intake over at least 6 months following underfeeding compared with YNW adults, and a reduction in their perceived frequency of hunger may be a contributing factor.
Assuntos
Envelhecimento/fisiologia , Composição Corporal/fisiologia , Dieta Redutora , Fome/fisiologia , Aumento de Peso/fisiologia , Adulto , Idoso , Ingestão de Energia , Feminino , Humanos , Masculino , Valores de ReferênciaRESUMO
Pericardial cysts are not common and rarely cause symptoms. We report a unique case of a 15-year-old male patient with cardiac tamponade clinically diagnosed who was referred for echocardiography. Transthoracic echocardiography revealed, in addition to a large pericardial effusion associated with echocardiographic signs of cardiac tamponade, an 8 x 5 cm echofree image suggesting a pericardial cyst adjacent to the right atrium. Immediately after pericardiocentesis, yielding a serosanguinous liquid, the patient showed striking clinical improvement and echocardiography demonstrated minimal pericardial effusion with persistence of the cystic image. At surgery a pericardial cyst containing a sanguinous fluid was found and the pathologic findings were consistent with hematic pericardial cyst. Thus echocardiography played a fundamental role for the diagnosis and treatment of the rare complication of a pericardial cyst documented in this patient.
Assuntos
Tamponamento Cardíaco/etiologia , Cisto Mediastínico/complicações , Adolescente , Tamponamento Cardíaco/diagnóstico por imagem , Ecocardiografia , Humanos , Masculino , Cisto Mediastínico/diagnóstico por imagem , Derrame Pericárdico/diagnóstico por imagem , Derrame Pericárdico/etiologia , PunçõesRESUMO
BACKGROUND: Many scales have been proposed for the brief nutritional assessment of older persons, with the goal of increasing undernutrition detection and the detection of nutritional risk. The Mini-Nutritional Assessment (Guigoz et al., 1994) has been increasingly used worldwide, but its efficacy has been assessed in few countries. OBJECTIVES: This study aimed to assess, through complete clinical evaluation, anthropometric measurements and laboratorial tests, the nutritional state of older persons living in the community and compare the results with the score obtained by the application of the Mini Nutritional Assessment. DESIGN: Forty-two persons aged 60 years or older (55% women, mean age 70.9 years) were studied. All volunteers were submitted to a criterious clinical evaluation, anthropometric measures and laboratorial testing (serum albumin, hemoglobin, lymphocite count, iron and unsatured iron binding capacity). RESULTS: Twenty-seven volunteers (64%) were considered eutrophic, 12 volunteers were considered obese (28,6%) and three volunteers were considered undernourished. Thirteen volunteers were classified as in risk of undernutrition by the Mini-Nutritional Assessment score, 29 scored within the normal range and no volunteer was considered to be undernourished. The Mini Nutritional Assessment score was significantly associated with age and with the unsatured iron binding capacity. When compared to the final nutritional diagnosis, the questionnaire showed 100% sensibility and 74.3% specificity. CONCLUSION: This study detected a prevalence of undernutrition in the elderly living in the community similar to those described in developed countries. In this population, the Mini Nutritional Assessment showed to be specially efficient for the detection of nutritional risk.
Assuntos
Avaliação Geriátrica/métodos , Avaliação Nutricional , Distúrbios Nutricionais/diagnóstico , Inquéritos e Questionários/normas , Idoso , Antropometria , Brasil/epidemiologia , Feminino , Indicadores Básicos de Saúde , Humanos , Masculino , Distúrbios Nutricionais/epidemiologia , Inquéritos Nutricionais , Estado Nutricional , Reprodutibilidade dos Testes , Medição de Risco , Fatores de Risco , Sensibilidade e EspecificidadeRESUMO
CONTEXT: The loss of body weight and fat late in life is associated with premature death and increased risk of disability, even after excluding elderly subjects who have a preexisting disease. Although it is important to recognize that periods of substantially positive or negative energy balance and body weight fluctuation occur as a normal part of life, weight losses greater than 5% over 6 months should be investigated. We can divide the major causes of weight loss in the elderly into 4 categories: social, psychiatric, due to medical conditions, and age-related. The clinical evaluation should include a careful history and physical examination. If these fail to provide clues to the weight loss, simple diagnostic tests are indicated. A period of watchful waiting is preferable to blind pursuit of additional diagnostic testing that may yield few useful data, if the results of these initial tests are normal. The first step in managing patients with weight loss is to identify and treat any specific causative or contributing conditions and to provide nutritional support when indicated. Non-orexigenic drugs have found an established place in the management of protein-energy malnutrition. Early attention to nutrition and prevention of weight loss during periods of acute stress, particularly during hospitalization, may be extremely important, as efforts directed at re-feeding are often unsuccessful. DESIGN: Narrative review.
Assuntos
Emaciação/etiologia , Redução de Peso/fisiologia , Fatores Etários , Idoso , Envelhecimento/fisiologia , Causas de Morte , Diagnóstico Diferencial , Emaciação/fisiopatologia , Emaciação/terapia , Feminino , Humanos , MasculinoRESUMO
BACKGROUND: There is no consensus regarding the accuracy of bioimpedance for the determination of body composition in older persons. OBJECTIVE: This study aimed to compare the assessment of lean body mass of healthy older volunteers obtained by the deuterium dilution method (reference) with those obtained by two frequently used bioelectrical impedance formulas and one formula specifically developed for a Latin-American population. DESIGN: A cross-sectional study. PARTICIPANTS: Twenty one volunteers were studied, 12 women, with mean age 72±6.7 years. SETTING: Urban community, Ribeirão Preto, Brazil. MEASUREMENT: Fat free mass was determined, simultaneously, by the deuterium dilution method and bioelectrical impedance; results were compared. In bioelectrical impedance, body composition was calculated by the formulas of Deuremberg, Lukaski and Bolonchuck and Valencia et al. RESULTS: Lean body mass of the studied volunteers, as determined by bioelectrical impedance was 37.8±9.2 kg by the application of the Lukaski e Bolonchuk formula, 37.4±9.3 kg (Deuremberg) and 43.2±8.9 kg (Valencia et. al.). The results were significantly correlated to those obtained by the deuterium dilution method (41.6±9.3 Kg), with r=0.963, 0.932 and 0.971, respectively. Lean body mass obtained by the Valencia formula was the most accurate. CONCLUSION: In this study, lean body mass of older persons obtained by the bioelectrical impedance method showed good correlation with the values obtained by the deuterium dilution method. The formula of Valencia et al., developed for a Latin-American population, showed the best accuracy.
Assuntos
Composição Corporal , Óxido de Deutério , Impedância Elétrica , Técnicas de Diluição do Indicador/normas , Matemática/normas , Tecido Adiposo/metabolismo , Idoso , Brasil , Estudos Transversais , Feminino , Humanos , Masculino , Músculo Esquelético/fisiologia , Obesidade/diagnósticoRESUMO
BACKGROUND: The prevention and treatment of diseases related to changes in body composition require accurate methods for the measurement of body composition. However, few studies have dealt specifically with the assessment of body composition of undernourished older subjects by different methodologies. OBJECTIVES: To assess the body composition of undernourished older subjects by two different methods, dual energy x-ray absorptiometry (DXA) and bioelectric impedance (BIA), and to compare results with those of an eutrophic group. DESIGN: The study model was cross-sectional; the study was performed at the University Hospital of the School of Medicine of Ribeirão Preto, University of São Paulo, Brazil. PARTICIPANTS: Forty-one male volunteers aged 62 to 91 years. The groups were selected on the basis of anamnesis, physical examination and nutritional assessment according to the Mini Nutritional Assessment (MNA) score. Body composition was assessed by DXA and BIA. RESULTS: Body weight, arm and calf circumference, body mass index (BMI), fat free mass (FFM) and fat mass (FM) were significantly lower in the undernourished group as compared to the eutrophic group. There were no significant differences between FFM and FM mean values determined by DXA and BIA in both groups, but the agreement between methods in the undernourished group was less strong. CONCLUSION: Our results suggest caution when BIA is to be applied in studies including undernourished older subjects. This study does not support BIA as an accurate method for the individual assessment of body composition.
Assuntos
Composição Corporal , Impedância Elétrica , Avaliação Geriátrica , Desnutrição , Avaliação Nutricional , Absorciometria de Fóton/métodos , Idoso , Idoso de 80 Anos ou mais , Pesos e Medidas Corporais , Brasil , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Reprodutibilidade dos TestesRESUMO
Salt sensitivity and insulin resistance are correlated with higher cardiovascular risk. There is no information about changes in salt sensitivity (SS) and insulin sensitivity (IS) after a chronic salt overload in humans. The aim of this study was to evaluate these parameters in the elderly. Seventeen volunteers aged 70.5 +/- 5.9 years followed a low-salt diet (LSD) for 1 week and a high-salt diet (HSD) for 13 weeks. We evaluated SS after one week (HSD1) and after 13 weeks (HSD13), and subjects' IS and lipids on their usual diet (UD) at HSD1, and at HSD13. Blood pressure (BP) was measured at each visit and ambulatory blood pressure monitoring (ABPM) was performed twice. SS was the same at HSD1 and HSD13. Systolic BP was lower on LSD than on UD (P = 0.01), HSD1 (P < 0.01) and HSD13 (P < 0.01). When systolic and diastolic BP were evaluated by ABPM, they were higher at HSD13 during the 24-h period (P = 0.03 and P < 0.01) and during the wakefulness period (P = 0.02 and P < 0.01) compared to the UD. Total cholesterol was higher (P = 0.04) at HSD13 than at HSD1. Glucose and homeostasis model assessment (HOMA) were lower at HSD1 (P = 0.02 and P = 0.01) than at HSD13. Concluding, the extension of HSD did not change the SS in an elderly group. The higher IS found at HSD1 did not persist after a longer HSD. A chronic HSD increased BP as assessed by ABPM.
Assuntos
Pressão Sanguínea/efeitos dos fármacos , Resistência à Insulina/fisiologia , Cloreto de Sódio na Dieta/farmacologia , Idoso , Monitorização Ambulatorial da Pressão Arterial , Estudos de Casos e Controles , Dieta Hipossódica , Feminino , Homeostase , Humanos , Masculino , Cloreto de Sódio na Dieta/administração & dosagemRESUMO
BACKGROUND: A high purified protein intake has been shown to induce urinary calcium loss. However, these findings could not be reproduced with a high-protein meat diet. Also, most studies have been carried out in young subjects and the applicability of their results to the elderly population on a mixed vegetable:animal diet remains unclear. OBJECTIVES: To study whether a mixed vegetable:animal high-protein intake increases urinary calcium loss in elderly volunteers, as has been shown for younger subjects on a purified high-protein intake. METHODS: Eight male volunteers, with ages ranging from 66 to 88 years, recruited from the University Hospital Geriatric Medicine Outpatients Clinic, were studied. 24-hour urinary calcium, phosphorus, and creatinine were measured during a period of usual protein intake (approximately 0.6 g/kg/day) and during 7 days of vegetable:animal (1:1) high-protein intake (2 g/kg/day). Calcium and phosphorus intake were adjusted to be kept constant (1 g/day of each) during the whole study. RESULTS: Mean calcium urinary levels did not change significantly during the study (1.89 and 1.83 mmol/24 h during the usual and high-protein diet, respectively). Urinary phosphorus and creatinine levels also remained stable throughout the entire study. CONCLUSIONS: This study has not detected any increased calcium urinary excretion in male elderly volunteers submitted to the mixed vegetable:animal high-protein diet. Therefore, it does not support the suggestion that a high-protein intake is a risk factor for urinary calcium loss in elderly men.
Assuntos
Cálcio/urina , Proteínas Alimentares/administração & dosagem , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Ácido Ascórbico/sangue , Índice de Massa Corporal , Cálcio da Dieta/administração & dosagem , Creatina/efeitos dos fármacos , Creatina/urina , Ácido Fólico/sangue , Humanos , Masculino , Fósforo na Dieta/administração & dosagem , Dobras Cutâneas , Vitamina A/sangue , beta Caroteno/sangueRESUMO
OBJECTIVES: To investigate the effects of oats, a cereal rich in soluble fiber, on body composition changes and dietary compliance during consumption of a weight loss diet. METHODS: Subjects were 41 healthy men and women aged 18 to 78 years. Weight maintenance energy requirements were established over two weeks during consumption of a control diet with low soluble fiber content. Subjects then consumed a hypocaloric diet for six weeks, either consuming a low soluble fiber control diet or a diet containing 45 g/1000 kcal rolled oats, a whole grain cereal rich in soluble fiber (mean energy deficit -895+/-18 kcal/day relative to weight maintenance energy requirements). Changes in body fat and fat-free mass were determined by underwater weighing, and dietary compliance was assessed using the urinary osmolar excretion rate technique. In a final phase of the study, subjects ate ad libitum for six months, and changes in body weight and composition were monitored. RESULTS: There was no significant effect of the oat-containing diet on body weight or composition changes during the hypocaloric regimen or in the subsequent ad libitum period. In addition, fecal energy excretion was not significantly different between groups. However, there were non-significant trends indicating reduced hunger in the oat group compared to controls (frequency of hunger 2.5+/-0.5 vs. 3.6+/-0.4, P=0.1). In addition, fewer oat subjects were non-compliant (four versus seven subjects dropped out or had urinary osmolar excretions greater than 130% of values predicted from dietary intake), but again the difference was not significant. CONCLUSIONS: These results suggest that use of a cereal rich in soluble fiber in a closely monitored hypocaloric feeding regimen does not improve weight loss or dietary compliance. Further studies are needed to examine the possibility that cereals containing soluble fiber may have effects on hunger and dietary compliance that could be important in less tightly controlled protocols than the one described here.
Assuntos
Composição Corporal/fisiologia , Dieta Redutora , Fibras na Dieta/administração & dosagem , Grão Comestível , Cooperação do Paciente , Adulto , Idoso , Avena/química , Composição Corporal/efeitos dos fármacos , Fezes/química , Feminino , Humanos , Fome/efeitos dos fármacos , Fome/fisiologia , Masculino , Pessoa de Meia-Idade , Redução de Peso/efeitos dos fármacos , Redução de Peso/fisiologiaRESUMO
The effect of aging on energy regulation remains controversial. We compared the effects of underfeeding on changes in energy expenditure and respiratory quotient in young normal weight men and women [YNW, age 25.7 +/- 3.2 y(SD), body mass index (BMI) 23.1 +/- 1.6 kg/m(2)], young overweight men and women (YOW, age 26.1 +/- 3.5 y, BMI 27.7 +/- 2.1 kg/m(2)) and older (OLD) men and women (age 68.4 +/- 3.3 y, BMI 27.4 +/- 3.4 kg/m(2)). The thermic effect of feeding (TEF) during weight maintenance, and changes in resting energy expenditure (REE) and respiratory quotient were determined in response to undereating by an average 3.75 MJ/d for 6 wk. In addition, body composition was measured. No significant differences among the groups were observed in TEF, fasting and postprandial respiratory quotient, or the change in fasting respiratory quotient with underfeeding. However, REE adjusted for fat-free mass and fat mass was significantly lower in OLD subjects compared with YNW and YOW subjects (P < 0.05). In addition, the REE response to weight change was significantly attenuated in the OLD subjects (P = 0.023). These data suggest that the responsiveness of energy expenditure to negative energy balance is attenuated in old age, and provide further support for the hypothesis that mechanisms of energy regulation are broadly disregulated in old age.
Assuntos
Envelhecimento/fisiologia , Metabolismo Energético/fisiologia , Comportamento Alimentar , Adulto , Idoso , Análise de Variância , Índice de Massa Corporal , Peso Corporal , Ingestão de Energia , Jejum , Feminino , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Redução de PesoRESUMO
Salt sensitivity and insulin resistance are correlated with higher cardiovascular risk. There is no information about changes in salt sensitivity (SS) and insulin sensitivity (IS) after a chronic salt overload in humans. The aim of this study was to evaluate these parameters in the elderly. Seventeen volunteers aged 70.5 ± 5.9 years followed a low-salt diet (LSD) for 1 week and a high-salt diet (HSD) for 13 weeks. We evaluated SS after one week (HSD1) and after 13 weeks (HSD13), and subjects IS and lipids on their usual diet (UD) at HSD1, and at HSD13. Blood pressure (BP) was measured at each visit and ambulatory blood pressure monitoring (ABPM) was performed twice. SS was the same at HSD1 and HSD13. Systolic BP was lower on LSD than on UD (P = 0.01), HSD1 (P < 0.01) and HSD13 (P < 0.01). When systolic and diastolic BP were evaluated by ABPM, they were higher at HSD13 during the 24-h period (P = 0.03 and P < 0.01) and during the wakefulness period (P = 0.02 and P < 0.01) compared to the UD. Total cholesterol was higher (P = 0.04) at HSD13 than at HSD1. Glucose and homeostasis model assessment (HOMA) were lower at HSD1 (P = 0.02 and P = 0.01) than at HSD13. Concluding, the extension of HSD did not change the SS in an elderly group. The higher IS found at HSD1 did not persist after a longer HSD. A chronic HSD increased BP as assessed by ABPM.