Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 31
Filtrar
2.
Diving Hyperb Med ; 50(4): 386-390, 2020 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-33325020

RESUMO

INTRODUCTION: We have previously shown that hyperbaric oxygen treatment (HBOT) increased insulin sensitivity in men who were obese or overweight, both with and without type 2 diabetes. The aim of this study was to test whether this insulin-sensitising effect is seen in hyperbaric air (HA). METHODS: Men with type 2 diabetes who were obese or overweight were randomised to two groups: HBOT (n = 13) or HA (n = 11). A hyperinsulinaemic euglycaemic glucose clamp (80 mU·m-2·min-1) was performed at baseline and during hyperbaric intervention. Both groups were compressed to 203 kPa (two atmospheres absolute) for 90 minutes followed by a linear 30-minute decompression. The HBOT group breathed oxygen via a hood while the HA group breathed chamber air. Insulin sensitivity was assessed from the glucose infusion rate (GIR) during the last 30 minutes in the hyperbaric chamber (SS1) and the first 30 minutes after exit (SS2). Data were analysed for within-group effect by paired student t-test and between-group effect by one-way ANOVA. RESULTS: HBOT increased GIR by a mean 26% at SS1 (P = 0.04) and 23% at SS2 (P = 0.018). There was no significant change in GIR during or after HA. A between-group effect was evident for the change in GIR at SS1 in HBOT vs HA (P = 0.036). CONCLUSIONS: The pathway by which insulin sensitivity is increased in men with type 2 diabetes requires the high oxygen partial pressures of HBOT and should be further investigated. Insulin sensitivity was not changed in hyperbaric air.


Assuntos
Diabetes Mellitus Tipo 2 , Oxigenoterapia Hiperbárica , Resistência à Insulina , Diabetes Mellitus Tipo 2/terapia , Humanos , Insulina , Masculino , Oxigênio
3.
Endocrine ; 55(2): 618-624, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27601019

RESUMO

Dopamine agonists are the first line of therapy for prolactinomas, with high rates of biochemical control and tumour shrinkage. Toxicity is considered to be low and manageable by switching of agents and dose reduction. Dopamine agonist-induced impulse control disorders are well described in the neurology setting, but further data are required regarding this toxicity in prolactinoma patients. We performed a multicenter retrospective cohort study of eight men with prolactinomas and associated central hypogonadism. The eight men had no prior history of psychiatric disease, but each developed disruptive hypersexuality whilst on dopamine agonist therapy at various doses. Cabergoline, bromocriptine and quinagolide were all implicated. Hypersexuality had manifold consequences, including relationship discord, financial loss, reduced work performance, and illicit activity. We hypothesise that this phenomenon is due to synergy between reward pathway stimulation by dopamine agonists, together with rapid restoration of the eugonadal state after prolonged hypogonadism. We refer here to this distinct drug toxicity as 'dopa-testotoxicosis'. Given the profound impact in these patients and their families, cessation of dopamine agonists should be considered in men who develop hypersexuality, and pituitary surgery may be required to facilitate this. Awareness of this distinct impulse control disorder should enable further research into the prevalence, natural history and management of dopa-testotoxicosis. The condition is likely under-reported due to the highly personal nature of the symptoms and we suggest a simple written questionnaire to screen for hypersexuality and other behavioural symptoms within the first six months of dopamine agonist treatment.


Assuntos
Aminoquinolinas/efeitos adversos , Bromocriptina/efeitos adversos , Agonistas de Dopamina/uso terapêutico , Ergolinas/efeitos adversos , Hipogonadismo/tratamento farmacológico , Neoplasias Hipofisárias/tratamento farmacológico , Prolactinoma/tratamento farmacológico , Disfunções Sexuais Fisiológicas/induzido quimicamente , Adulto , Idoso , Aminoquinolinas/uso terapêutico , Bromocriptina/uso terapêutico , Cabergolina , Ergolinas/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
4.
BMC Res Notes ; 8: 151, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25884358

RESUMO

BACKGROUND: The difficulty of recruiting older people to clinical trials is well described, but there is limited information about effective ways to screen and recruit older people into trials, and the reasons for their reluctance to enrol. This paper examines recruitment efforts for a community-based health intervention study that targeted older adults. METHODS: One year randomized control trial. Undernourished men and women, aged ≥ 65 years and living independently in the community were recruited in three Australian states. Participants were allocated to either oral testosterone undecanoate and high calorie oral nutritional supplement or placebo medication and low calorie oral nutritional supplementation. Hospital admissions, functional status, nutritional health, muscle strength, and other variables were assessed. RESULTS: 4023 potential participants were identified and 767 were screened by a variety of methods: hospital note screening, referrals from geriatric health services, advertising and media segments/appearances. 53 participants (7% of total screened) were recruited. The majority of potentially eligible participants declined participation in the trial after reading the information sheet. Media was the more successful method of recruiting, whereas contacting people identified by screening a large number of hospital records was not successful in recruiting any participants. CONCLUSION: Recruitment of frail and older participants is difficult and multiple strategies are required to facilitate participation. TRIAL REGISTRATION: Australian Clinical Trial Registry: ACTRN 12610000356066 date registered 4/5/2010.


Assuntos
Androgênios/administração & dosagem , Suplementos Nutricionais , Desnutrição/dietoterapia , Participação do Paciente/estatística & dados numéricos , Seleção de Pacientes , Testosterona/análogos & derivados , Idoso , Idoso de 80 Anos ou mais , Austrália , Dieta/métodos , Feminino , Idoso Fragilizado , Serviços de Saúde para Idosos , Hospitalização , Humanos , Vida Independente , Masculino , Desnutrição/fisiopatologia , Força Muscular/efeitos dos fármacos , Participação do Paciente/psicologia , Testosterona/administração & dosagem
5.
Asia Pac J Clin Nutr ; 23(3): 394-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25164449

RESUMO

Malnutrition is a major problem in hospitalised older people. Many nutrition screening tools are available for malnutrition identification, however little is known about their prognostic ability. This prospective, observational study investigated the prognostic value of three nutritional screening tools in a Geriatric Evaluation and Management Unit: the Geriatric Nutritional Risk Index (GNRI), the Mini Nutritional Assessment (MNA) and the Mini Nutritional Assessment short form (MNA-SF), incorporating either body mass index or calf circumference. Poor six- month outcome was defined as new admission to higher level residential care or mortality at six months post-discharge. Predictive ability of poor outcome was assessed by logistic regression models, adjusting for age, gender, cognition and co-morbidity. Predictive accuracy was determined by area under Receiver Operator Characteristic curves, sensitivity, specificity, predictive values and Youden Index. One hundred and seventy-two consecutive patients with a mean (SD) age=85.2 (6.4) years were included in the study. Malnutrition was identified in 31% of patients using the MNA and was associated with a higher risk of poor six-month outcome when identified by the MNA (OR, 95% CI=3.29, 1.17-9.23) and the GNRI (OR, 95% CI=2.84, 1.31-6.19), but not by the MNA-SF. All screening tools lacked discriminative power for outcome prediction. The MNA and GNRI were useful clinical predictors of poor six-month outcome, although their accuracy of prediction was low. Nutritional screening remains a priority in the routine assessment of hospitalised older people.


Assuntos
Avaliação Geriátrica/métodos , Hospitalização/estatística & dados numéricos , Desnutrição/diagnóstico , Desnutrição/epidemiologia , Avaliação Nutricional , Avaliação de Resultados da Assistência ao Paciente , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Pesos e Medidas Corporais/métodos , Pesos e Medidas Corporais/estatística & dados numéricos , Feminino , Avaliação Geriátrica/estatística & dados numéricos , Instituição de Longa Permanência para Idosos/estatística & dados numéricos , Humanos , Perna (Membro) , Estudos Longitudinais , Masculino , Casas de Saúde/estatística & dados numéricos , Estado Nutricional/fisiologia , Razão de Chances , Valor Preditivo dos Testes , Prevalência , Estudos Prospectivos , Curva ROC , Reprodutibilidade dos Testes , Risco , Sensibilidade e Especificidade , Austrália do Sul/epidemiologia
6.
Appetite ; 68: 147-51, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23665299

RESUMO

BACKGROUND: Sodium intake is high in people with type 2 diabetes (T2DM). The aim of this study was to investigate whether urinary sodium excretion can be reduced by educating people with T2DM to read food labels and choose low sodium products. METHOD: In a 3 month randomised controlled trial, 78 men (n=49) and women (n=29) with T2DM were recruited from a Diabetes Centre at a University teaching hospital. The intervention group was educated in a single session to use the nutrition information panel on food labels to choose products which complied with the Food Standards Australia New Zealand (FSANZ) guideline of <120 mg sodium/100 g food. The control group continued on their usual diet. The primary outcome measure was 24h urinary sodium excretion which was performed at baseline and 3 months. Data was analysed using repeated measures analysis of variance, independent samples t-test and Pearson's correlations. RESULTS: At 3 months mean urinary sodium excretion was unchanged in the intervention (174±13 mmol/24 h and 175±13 mmol/24 h) and control group (167±15mmol/24h and 161±13 mmol/24 h), and there was no between group difference (p>0.05). CONCLUSION: Sodium excretion was not reduced following the label reading education provided to this group of people with T2DM.


Assuntos
Diabetes Mellitus Tipo 2/urina , Dieta/métodos , Dieta/estatística & dados numéricos , Rotulagem de Alimentos , Educação em Saúde/métodos , Sódio na Dieta/urina , Austrália , Dieta Hipossódica/métodos , Dieta Hipossódica/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
J Am Med Dir Assoc ; 14(9): 642-8, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23522494

RESUMO

Ideal body weight for maximum life expectancy increases with advancing age. Older people, however, tend to weigh less than younger adults, and old age is also associated with a tendency to lose weight. Weight loss in older people is associated with adverse outcomes, particularly if unintentional, and initial body weight is low. When older people lose weight, more of the tissue lost is lean tissue (mainly skeletal muscle) than in younger people. When excessive, the loss of lean muscle tissue results in sarcopenia, which is associated with poor health outcomes. Unintentional weight loss in older people may be a result of protein-energy malnutrition, cachexia, the physiological anorexia of aging, or a combination of these. The physiological anorexia of aging is a decrease in appetite and energy intake that occurs even in healthy people and is possibly caused by changes in the digestive tract, gastrointestinal hormone concentrations and activity, neurotransmitters, and cytokines. A greater understanding of this decrease in appetite and energy intake during aging, and the responsible mechanisms, may aid the search for ways to treat undernutrition and weight loss in older people.


Assuntos
Envelhecimento/fisiologia , Anorexia/etiologia , Peso Corporal , Caquexia/etiologia , Desnutrição Proteico-Calórica/etiologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Anorexia/fisiopatologia , Anorexia/prevenção & controle , Caquexia/fisiopatologia , Caquexia/prevenção & controle , Ingestão de Energia , Humanos , Expectativa de Vida , Desnutrição Proteico-Calórica/fisiopatologia , Desnutrição Proteico-Calórica/prevenção & controle , Fatores de Risco
8.
Diabetes Res Clin Pract ; 97(2): 258-66, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22446097

RESUMO

AIMS: Liraglutide reduces bodyweight in patients with type 2 diabetes mellitus (T2DM). This study aimed to investigate the mechanisms underlying this effect. METHODS: The comparative effects of liraglutide, glimepiride and placebo on energy intake, appetite, nausea, gastric emptying, antral distension, bodyweight, gastrointestinal hormones, fasting plasma glucose and resting energy expenditure (REE), were assessed in subjects with T2DM randomised to treatment A (liraglutide-placebo), B (placebo-glimepiride) or C (glimepiride-liraglutide). Assessments were performed at the end of each 4-week treatment period. RESULTS: Energy intake was less (NS) with liraglutide vs placebo and glimepiride, and 24-h REE was higher (NS) with liraglutide vs placebo and glimepiride. Fasting hunger was less (p=0.01) with liraglutide vs placebo and glimepiride, and meal duration was shorter with liraglutide (p=0.002) vs placebo. Paracetamol AUC(0-60 min) and C(max) were less (p<0.01) and fasting peptide YY was lower (p ≤ 0.001) after liraglutide vs placebo and glimepiride. Bodyweight reductions of 1.3 and 2.0 kg were observed with liraglutide vs placebo and glimepiride (p<0.001). There were no differences on antral distension, nausea, or other gastro-intestinal hormones. CONCLUSION: Liraglutide caused decreased gastric emptying and increased reduction in bodyweight. The mechanisms of the liraglutide-induced weight-loss may involve a combined effect on energy intake and energy expenditure.


Assuntos
Apetite/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Ingestão de Energia/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Esvaziamento Gástrico/efeitos dos fármacos , Peptídeo 1 Semelhante ao Glucagon/análogos & derivados , Peptídeo 1 Semelhante ao Glucagon/administração & dosagem , Obesidade/tratamento farmacológico , Compostos de Sulfonilureia/administração & dosagem , Adolescente , Adulto , Idoso , Austrália , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Humanos , Hipoglicemiantes/administração & dosagem , Liraglutida , Masculino , Pessoa de Meia-Idade , Obesidade/metabolismo , Obesidade/fisiopatologia , Compostos de Sulfonilureia/farmacologia , Adulto Jovem
9.
BMC Geriatr ; 11: 66, 2011 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-22023735

RESUMO

BACKGROUND: Weight loss and under-nutrition are relatively common in older people, and are associated with poor outcomes including increased rates of hospital admissions and death. In a pilot study of 49 undernourished older, community dwelling people we found that daily treatment for one year with a combination of testosterone tablets and a nutritional supplement produced a significant reduction in hospitalizations. We propose a larger, multicentre study to explore and hopefully confirm this exciting, potentially important finding (NHMRC project grant number 627178). METHODS/DESIGN: One year randomized control trial where subjects are allocated to either oral testosterone undecanoate and high calorie oral nutritional supplement or placebo medication and low calorie oral nutritional supplementation. 200 older community-dwelling, undernourished people [Mini Nutritional Assessment score <24 and either: a) low body weight (body mass index, in kg/m(2): <22) or b) recent weight loss (>7.5% over 3 months)]. Hospital admissions, quality-adjusted life years, functional status, nutritional health, muscle strength, body composition and other variables will be assessed. DISCUSSION: The pilot study showed that combined treatment with an oral testosterone and a supplement drink was well tolerated and safe, and reduced the number of people hospitalised and duration of hospital admissions in undernourished, community dwelling older people. This is an exciting finding, as it identifies a treatment which may be of substantial benefit to many older people in our community. We now propose to conduct a multi-centre study to test these findings in a substantially larger subject group, and to determine the cost effectiveness of this treatment. TRIAL REGISTRATION: Australian Clinical Trial Registry: ACTRN 12610000356066.


Assuntos
Suplementos Nutricionais , Desnutrição/dietoterapia , Desnutrição/tratamento farmacológico , Admissão do Paciente , Testosterona/análogos & derivados , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Feminino , Humanos , Masculino , Desnutrição/epidemiologia , Estado Nutricional/efeitos dos fármacos , Estado Nutricional/fisiologia , Admissão do Paciente/tendências , Projetos Piloto , Anos de Vida Ajustados por Qualidade de Vida , Testosterona/administração & dosagem , Resultado do Tratamento
10.
Med Clin North Am ; 95(3): 579-93, xi, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21549879

RESUMO

Weight loss is common in older people. It is associated with increased morbidity and mortality, particularly when unintentional, excessive (>5% body weight), or associated with low body weight (body mass index <22 kg/m(2)). It is often unrecognized, the associated adverse effects not appreciated, and underlying causes not addressed. Intentional weight loss by overweight older people is probably appropriate only when functional problems have resulted from the excess weight. It is important to include, wherever possible, exercise in weight-loss measures to preserve skeletal muscle mass.


Assuntos
Anorexia/fisiopatologia , Nível de Saúde , Desnutrição/fisiopatologia , Atrofia Muscular/fisiopatologia , Prevenção Primária/organização & administração , Redução de Peso , Idoso , Idoso de 80 Anos ou mais , Anorexia/complicações , Índice de Massa Corporal , Feminino , Avaliação Geriátrica/métodos , Serviços de Saúde para Idosos/organização & administração , Humanos , Masculino , Desnutrição/complicações , Pessoa de Meia-Idade , Estado Nutricional , Fatores de Risco , Sarcopenia/etiologia , Sarcopenia/prevenção & controle
11.
Br J Nutr ; 106(3): 417-24, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21396142

RESUMO

Postprandial hypotension may be influenced by the digestion of fat. The aim of the present study was to evaluate the hypothesis that products of fat digestion mediate the hypotensive response to fat. In part A of the study, nine healthy older subjects were studied on three separate occasions in randomised order. Blood pressure, heart rate (HR), plasma TAG and gastric emptying were measured following the ingestion of equivolaemic drinks: (1) 300 ml of high-fat drink (88 % fat); (2) fat drink mixed with 120 mg orlistat (lipase inhibitor); (3) water (control). In part B of the study, ten healthy older subjects were studied on two separate occasions. Blood pressure, HR, plasma TAG and superior mesenteric artery flow were measured during 90 min intraduodenal infusions of 10 % intralipid (2·7 ml/min), with and without 120 mg orlistat. Oral fat ingestion was associated with decreases in systolic and diastolic blood pressures (both P = 0·0001) that were greater when orlistat was co-administered (both P < 0·05), and an increase in HR (P = 0·0001) that was inhibited by orlistat co-administration (P < 0·03). Gastric emptying was slowed by oral fat digestion, and orlistat administration inhibited this slowing (P < 0·04). Intraduodenal fat infusion was not associated with changes in blood pressure but increased HR (P < 0·0001), an effect attenuated by orlistat (P < 0·05). In conclusion, orlistat potentiates the hypotensive response to oral fat in older adults, possibly as a result of faster gastric emptying of fat. The results do not support a role for fat digestion in lowering blood pressure.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Gorduras na Dieta/farmacologia , Esvaziamento Gástrico/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Hipotensão/fisiopatologia , Lactonas/farmacologia , Lipídeos/farmacologia , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea/fisiologia , Gorduras na Dieta/administração & dosagem , Feminino , Frequência Cardíaca/fisiologia , Humanos , Lipídeos/administração & dosagem , Masculino , Orlistate , Período Pós-Prandial
12.
Interdiscip Top Gerontol ; 37: 20-36, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20703053

RESUMO

Although obesity in young people is a risk factor for morbidity and mortality, the effect of obesity in the elderly is much more complex. For example, the body weight associated with maximal survival increases with increasing age. Even more striking is the 'obesity paradox' in the elderly, in which overweight is associated with increased risk for cardiovascular disease but decreased mortality from these diseases. Thus, although intentional weight loss by obese older people is probably safe, and likely to be beneficial if they have obesity-related morbidities, caution should be exercised in recommending weight loss to overweight older people on the basis of body weight alone. Methods of achieving weight loss in older adults are the same as in younger adults. Weight loss diets should be combined with an exercise program, if possible, to preserve muscle mass, as dieting results in loss of muscle as well as fat, and older people have reduced skeletal muscle mass compared to younger adults. Weight-loss drugs have not been extensively studied in older people and there is the potential for drug side effects and interactions. Weight loss surgery appears to be safe and effective, although it probably produces less weight loss than in younger adults. Little is yet known about the outcomes of such surgery in people over 65 years.


Assuntos
Envelhecimento/fisiologia , Obesidade/complicações , Obesidade/fisiopatologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/terapia , Fatores de Risco
13.
Appetite ; 55(3): 473-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20800632

RESUMO

Human aging is associated with a reduction in appetite and food intake. Increased activity of the satiety hormone, cholecystokinin (CCK), may be partly responsible. This study aimed to determine whether an increase in fat and energy intake modifies the suppressive effects of CCK-8 on appetite and energy intake. Fourteen healthy older adults completed three separate dietary periods, a 14-day and a 7-day normal diet (ND; 8272 ± 480 kJ/day; 35% fat), and a 14-day high-fat diet (HFD; 11,642 ± 414 kJ/day; 43% fat), in randomised order. Immediately following each diet, subjects received, in single-blinded fashion, a 30-min intravenous infusion of either CCK-8 (1.5 ng/kg/min) (ND-CCK, HFD-CCK) or 0.9% saline (ND-SAL), the latter following only ND. Plasma CCK concentrations, appetite responses and energy intake at a buffet meal were determined. Energy intake at the buffet meal was higher on the ND-SAL study day (3349 ± 224 kJ), when compared with either ND-CCK (3023 ± 317 kJ) or HFD-CCK (2905 ± 316 kJ). The suppression of energy intake by CCK-8 infusion did not differ between the two diets. We conclude that suppression of energy intake by exogenous CCK-8 does not appear to be attenuated by incorporation of supplemental high-energy, high-fat drinks in the diet of healthy older adults.


Assuntos
Apetite/efeitos dos fármacos , Colecistocinina/farmacologia , Gorduras na Dieta/farmacologia , Suplementos Nutricionais , Ingestão de Energia/efeitos dos fármacos , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Colecistocinina/sangue , Feminino , Humanos , Infusões Intravenosas , Masculino , Método Simples-Cego
14.
Appetite ; 55(3): 407-12, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20670666

RESUMO

It is uncertain whether the postprandial suppression of ghrelin is dependent on digestion and absorption of nutrients or whether the presence of nutrients in the small intestine is sufficient. Twenty-four healthy young adults with a mean age of 23 ± 0.6 years were examined on 3 separate days after an overnight fast. Twelve subjects participated in Part A, and the other 12 subjects in Part B. In Part A, subjects consumed, in random order, one of three study drinks: 300 mL water; 300 mL high-fat drink, with and without, 120 mg orlistat. In Part B, subjects received, in random order, one of three drinks: 300 mL water; 300 mL sucrose, with and without, 100mg acarbose. In both parts gastric emptying as measured by 2-D ultrasound. In Part A, plasma ghrelin concentrations decreased following ingestion of the high-fat drink, but did not change with the high-fat-orlistat drink or water. In Part B, the suppression of plasma ghrelin following the sucrose drink, was attenuated by acarbose. Orlistat accelerated gastric emptying of the high-fat drink, while acarbose delayed gastric emptying of the sucrose drink. In conclusion, fat and carbohydrate digestion is required for maximal suppression of ghrelin secretion.


Assuntos
Gorduras na Dieta/metabolismo , Sacarose Alimentar/metabolismo , Digestão/fisiologia , Inibidores Enzimáticos/farmacologia , Retroalimentação Fisiológica , Grelina/sangue , Acarbose/farmacologia , Adolescente , Adulto , Digestão/efeitos dos fármacos , Feminino , Esvaziamento Gástrico , Grelina/metabolismo , Humanos , Lactonas/farmacologia , Masculino , Orlistate , Período Pós-Prandial , Valores de Referência , Sacarose/metabolismo , Adulto Jovem
15.
Eur J Nutr ; 48(3): 176-83, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19198916

RESUMO

BACKGROUND/OBJECTIVES: The determinants of plasma ghrelin concentrations including the effects of aging, gender, and body composition, are unclear. Appetite and energy intake decrease with advancing age, and there is a corresponding decline in total body lean tissue, and an increase in fat mass. METHODS: We measured fasting plasma ghrelin and insulin concentrations in 52 healthy subjects aged 22-82 years, and assessed body composition by dual energy X-ray absorptiometry. Energy intake was estimated from diet diaries. RESULTS: Fasting ghrelin concentrations were not significantly correlated with age and energy intake (R = 0.07, P = 0.62; and R = -0.14, P = 0.34 respectively) on univariate regression analysis, and ghrelin concentrations were higher in females than males (2886.8 +/- 182.1 pg/ml vs 2082.5 +/- 121.2 pg/ml; P = 0.001). Ghrelin was inversely related to body mass index (R = -0.328, P = 0.018), fat-free body mass (R = -0.428, P = 0.002), and total skeletal muscle mass (R = -0.439, P = 0.001), but not related to body fat mass (R = 0.177, P = 0.208). On multiple regression analysis, total skeletal muscle mass (corrected for height) was the only significant negative predictor (P < 0.0001) of fasting ghrelin concentrations. CONCLUSIONS: In conclusion, in healthy adults, plasma ghrelin concentrations are not significantly influenced by age or energy intake per se, but relate to skeletal muscle mass.


Assuntos
Composição Corporal/fisiologia , Grelina/sangue , Músculo Esquelético/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Índice de Massa Corporal , Ingestão de Energia , Jejum , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Caracteres Sexuais
16.
Am J Clin Nutr ; 89(3): 880-9, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19144729

RESUMO

BACKGROUND: In older people, undernutrition is associated with increased hospitalization rates and mortality. Because weight loss in older people often reflects a disproportionate reduction of skeletal muscle, anabolic treatments may be beneficial. OBJECTIVE: Our aim was to evaluate the hypothesis that testosterone treatment and a nutritional supplement have additive benefits. DESIGN: Oral testosterone undecanoate (40 mg daily for women, 80 mg twice daily for men) and an oral nutritional supplement (475 kcal/d) were administered, alone or combined, for 1 y to 49 community-dwelling, undernourished people [Mini Nutritional Assessment score <24 and low body weight (body mass index, in kg/m(2): <22) or recent weight loss (>7.5% over 3 mo)] aged >65 y (mean age: 77 y; 26 women and 23 men). Hospital admissions and other variables were assessed. RESULTS: In subjects receiving combined testosterone and nutritional supplements (n = 11), there were no hospital admissions, whereas there were 9 admissions (2 elective) in 13 subjects in the no-treatment group, 4 in the testosterone-treated group (n = 12), and 5 in the supplement-treated group (n = 13); P = 0.06 with no-treatment compared with combined treatment. When compared with the no-treatment group, the combined-treatment group had significantly fewer subjects admitted to hospital (0 compared with 5, P = 0.03), fewer days in hospital (0 compared with 74, P = 0.041), and a longer time to hospital admission (P = 0.017). CONCLUSIONS: In undernourished older people, combined treatment with testosterone and nutritional supplementation reduced the number of people hospitalized and the duration of hospital admissions, which are important endpoints in this group. Larger, confirmatory studies are now needed. This trial was registered before commencement at clinical trials.gov as NCT00117000.


Assuntos
Suplementos Nutricionais , Desnutrição/tratamento farmacológico , Testosterona/administração & dosagem , Fatores Etários , Idoso , Glicemia/metabolismo , Proteína C-Reativa/metabolismo , Eletrólitos/sangue , Feminino , Hematócrito , Hospitalização , Humanos , Masculino , Desnutrição/sangue , Antígeno Prostático Específico/sangue , Qualidade de Vida
17.
Nutrition ; 24(10): 950-6, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18653316

RESUMO

OBJECTIVE: We investigated the effects of vitamin D treatment on plasma glucose, serum insulin, and insulin sensitivity in vitamin D-deficient individuals without diabetes mellitus. METHODS: Thirty-three adults with vitamin D insufficiency (serum 25-hydroxyvitamin D concentration < or = 50 nmol/L) and without diabetes (12 with impaired glucose tolerance) were given two oral doses of 100 000 IU of cholecalciferol, 2 wk apart. Before the first dose and 2 wk after the second dose, a 75-g oral glucose tolerance test was performed. Plasma glucose, serum insulin, 25-hydroxyvitamin D, and parathyroid hormone concentrations were measured and insulin sensitivity was calculated from the oral glucose tolerance test. RESULTS: Mean serum 25-hydroxyvitamin D increased from 39.9 +/- 1.5 (SEM) to 90.3 +/- 4.3 nmol/L (P < 0.0001) and mean serum parathyroid hormone decreased from 6.7 +/- 1.2 to 4.5 +/- 0.6 pmol/L (P = 0.055). There was no change in blood glucose mean of 0-120 min (6.1 +/- 0.3 before versus 6.2 +/- 0.3 mmol/L, P = 0.63) or insulin mean of 0-120 min (47.8 +/- 5.35 versus 48.9 +/- 5.22 mU/L, P = 0.67) concentrations, and no change in insulin sensitivity (Avignon's insulin sensitivity index [SiM], P = 0.97; insulin sensitivity index at 0 and 120 min [ISI(0,120)], P = 0.74; Quantitative Insulin Sensitivity Check Index [QUICKI], P = 0.88; homeostasis model assessment [HOMA], P = 0.99) after vitamin D treatment. Results did not differ between subjects, with and without, impaired glucose tolerance. CONCLUSION: In adults without diabetes, correction of vitamin D deficiency is not associated with any effect on blood glucose or insulin concentrations or insulin sensitivity as assessed during an oral glucose tolerance test. These observations do not support an association between glucose/insulin homeostasis and vitamin D, at least in the short term.


Assuntos
Glicemia/metabolismo , Insulina/sangue , Deficiência de Vitamina D/tratamento farmacológico , Vitamina D/uso terapêutico , Adulto , Idoso , Área Sob a Curva , Glicemia/efeitos dos fármacos , Estudos de Coortes , Feminino , Intolerância à Glucose/sangue , Intolerância à Glucose/epidemiologia , Teste de Tolerância a Glucose , Humanos , Insulina/metabolismo , Secreção de Insulina , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Vitamina D/análogos & derivados , Vitamina D/sangue , Vitamina D/fisiologia , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/fisiopatologia , Adulto Jovem
18.
Nutrition ; 24(3): 279-85, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18187309

RESUMO

This review examines available evidence of links between abnormalities of glucose and insulin metabolism and vitamin D deficiency. Possible mechanisms of action of vitamin D include stimulation of insulin secretion and effects on insulin sensitivity. Sun exposure usually implies greater outdoor physical activity, which in itself may have beneficial effects on insulin sensitivity, unrelated to serum 25-hydroxyvitamin D concentrations. The observed associations in humans among vitamin D, insulin, and glucose metabolism have not yet been confirmed by intervention studies and, hence, a causal association has not been established. Clinical trials are needed to determine whether vitamin D treatment of vitamin D-deficient individuals is able to prevent or treat diabetes mellitus.


Assuntos
Glicemia/metabolismo , Insulina/metabolismo , Deficiência de Vitamina D/fisiopatologia , Vitamina D/biossíntese , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/prevenção & controle , Humanos , Resistência à Insulina , Secreção de Insulina , Luz Solar , Vitamina D/sangue
19.
Am J Clin Nutr ; 87(1): 156-61, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18175750

RESUMO

BACKGROUND: Postprandial hypotension frequently occurs in the elderly. The hypotensive response to a meal is triggered by the interaction of nutrients with the small intestine; information relating to the effects of different macronutrients on blood pressure (BP) is limited and inconsistent. OBJECTIVE: The objective of the study was to determine the effects of intraduodenal glucose, fat, and protein on BP, heart rate (HR), and superior mesenteric artery (SMA) blood flow in healthy older subjects. DESIGN: Eight subjects received intraduodenal glucose (64 g), fat (10% oil emulsion), protein (72 g whey), or saline (0.9%) at a rate of 2.7 mL/min for 90 min, followed by intraduodenal saline for 30 min. BP, HR, and SMA blood flow were measured. RESULTS: The falls in systolic BP during infusions of glucose, fat, and protein did not differ significantly (P=0.97); however, the fall occurred significantly earlier during the glucose infusion; (18+/-3.0 min) than during the fat (46+/-11.0 min; P=0.02) and protein 33+/-7 min; P=0.04) infusions. The increases in HR during glucose, fat, and protein infusions (P<0.0001 for all) did not differ significantly. SMA blood flow increased significantly after all infusions (P<0.001 for all), but the increase was significantly (P<0.05) lower after protein than after the other infusions. CONCLUSIONS: Intraduodenal glucose, fat, and protein decrease systolic BP in healthy older subjects, but the onset of the hypotensive response is earlier after glucose, and the effect of protein on SMA blood flow is less than that of the other nutrients.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Gorduras/farmacologia , Glucose/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Proteínas/farmacologia , Circulação Esplâncnica/efeitos dos fármacos , Idoso , Área Sob a Curva , Sistema Nervoso Autônomo/fisiologia , Pressão Sanguínea/fisiologia , Estudos Cross-Over , Diástole/efeitos dos fármacos , Diástole/fisiologia , Duodeno/efeitos dos fármacos , Duodeno/fisiologia , Gorduras/metabolismo , Feminino , Glucose/metabolismo , Frequência Cardíaca/fisiologia , Humanos , Hipotensão/etiologia , Intubação Gastrointestinal , Cinética , Masculino , Período Pós-Prandial , Proteínas/metabolismo , Método Simples-Cego , Circulação Esplâncnica/fisiologia , Sístole/efeitos dos fármacos , Sístole/fisiologia
20.
Am J Physiol Regul Integr Comp Physiol ; 294(1): R45-51, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18003795

RESUMO

There is evidence from studies in animals that the effects of both fat and CCK on gastrointestinal function and energy intake are attenuated by consumption of a high-fat diet. In humans, the effects of exogenous CCK-8 on antropyloroduodenal motility, plasma CCK, peptide YY (PYY), and ghrelin concentrations, appetite, and energy intake are attenuated by a high-fat diet. Ten healthy lean males consumed isocaloric diets (~15,400 kJ per day), containing either 44% (high-fat, HF) or 9% (low-fat, LF) fat, for 21 days in single-blind, randomized, cross-over fashion. Immediately following each diet (i.e., on day 22), subjects received a 45-min intravenous infusion of CCK-8 (2 ng.kg(-1).min(-1)), and effects on antropyloroduodenal motility, plasma CCK, PYY, ghrelin concentrations, hunger, and fullness were determined. Thirty minutes after commencement of the infusion, subjects were offered a buffet-style meal, from which energy intake (in kilojoules) was quantified. Body weight was unaffected by the diets. Fasting CCK (P < 0.05), but not PYY and ghrelin, concentrations were greater following the HF, compared with the LF, diet. Infusion of CCK-8 stimulated pyloric pressures (P < 0.01) and suppressed antral and duodenal pressures (P < 0.05), with no difference between the diets. Energy intake also did not differ between the diets. Short-term consumption of a HF diet increases fasting plasma CCK concentrations but does not affect upper gut motility, PYY and ghrelin, or energy intake during CCK-8 infusion, in a dose of 2 ng.kg(-1).min(-1), in healthy males.


Assuntos
Colecistocinina/sangue , Gorduras na Dieta/farmacologia , Ingestão de Energia/efeitos dos fármacos , Motilidade Gastrointestinal/efeitos dos fármacos , Grelina/sangue , Peptídeo YY/sangue , Sincalida/farmacologia , Adolescente , Adulto , Estudos Cross-Over , Duodeno/fisiologia , Jejum/metabolismo , Humanos , Infusões Intravenosas , Masculino , Antro Pilórico/fisiologia , Método Simples-Cego
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA