RESUMO
BACKGROUND: This paper describes the rationale and design of the ENVIS-ion Study, which aims to determine whether low-dose aspirin reduces the development of white matter hyper-intense (WMH) lesions and silent brain infarction (SBI). Additional aims include determining whether a) changes in retinal vascular imaging (RVI) parameters parallel changes in brain magnetic resonance imaging (MRI); b) changes in RVI parameters are observed with aspirin therapy; c) baseline cognitive function correlates with MRI and RVI parameters; d) changes in cognitive function correlate with changes in brain MRI and RVI and e) whether factors such as age, gender or blood pressure influence the above associations. METHODS/DESIGN: Double-blind, placebo-controlled trial of three years duration set in two Australian academic medical centre outpatient clinics. This study will enrol 600 adults aged 70 years and over with normal cognitive function and without overt cardiovascular disease. Subjects will undergo cognitive testing, brain MRI and RVI at baseline and after 3 years of study treatment. All subjects will be recruited from a 19,000-patient clinical outcome trial conducted in Australia and the United States that will evaluate the effects of aspirin in maintaining disability-free longevity over 5 years. The intervention will be aspirin 100 mg daily versus matching placebo, randomized on a 1:1 basis. DISCUSSION: This study will improve understanding of the mechanisms at the level of brain and vascular structure that underlie the effects of aspirin on cognitive function. Given the limited access and high cost of MRI, RVI may prove useful as a tool for the identification of individuals at high risk for the development of cerebrovascular disease and cognitive decline. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01038583.
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Aspirina/uso terapêutico , Infarto Encefálico/diagnóstico , Transtornos Cognitivos/prevenção & controle , Cognição/efeitos dos fármacos , Vasos Retinianos/patologia , Idoso , Envelhecimento/efeitos dos fármacos , Austrália , Método Duplo-Cego , Humanos , Imageamento por Ressonância Magnética , Testes Neuropsicológicos , Projetos de Pesquisa , Estados UnidosRESUMO
INTRODUCTION: the sensitive detection of mild cognitive impairment (MCI) in older adults is an important problem that requires objective assessment. We evaluated whether the computerised cognitive test battery, CogState, was as sensitive to MCI as two well-validated 'paper-and-pencil' tests, the Hopkins Verbal Learning Test (HVLT) and the Mini-Mental Status Examination (MMSE). METHODS: these tests were administered with a subjective memory questionnaire and an 'Activities of Daily Living' scale to 21 individuals with MCI and 98 cognitively healthy controls matched for sex, education and IQ levels. The sensitivity and specificity of the tests and their discrimination between groups were determined. RESULTS: the HVLT had a maximum discrimination between controls and MCI cases of 90%, compared with 86% for CogState and 65% for the MMSE. Only CogState showed correlations with subjective memory complaints (SMC) and activities of daily living for the whole cohort when controlled for age, sex and years of education. Logistic regression analyses showed that diagnosis (control:MCI) was predicted by HVLT and a CogState ratio score. Age was a significant predictor of HVLT performance, while age and SMC predicted CogState performance. The computerised test battery was well tolerated by older adults, but presentation speed was a limiting factor for some participants. CONCLUSIONS: overall, we conclude that the HVLT has better sensitivity for the detection of MCI in older adults than the CogState, but that CogState may enable the identification of cognitive deficits above and beyond impairments in memory.
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Transtornos Cognitivos/diagnóstico , Entrevista Psiquiátrica Padronizada , Testes Neuropsicológicos/normas , Aprendizagem Verbal , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Transtornos Cognitivos/psicologia , Computadores , Feminino , Seguimentos , Avaliação Geriátrica , Humanos , Masculino , Valor Preditivo dos Testes , Escalas de Graduação Psiquiátrica , Curva ROC , Inquéritos e QuestionáriosRESUMO
This methods paper outlines the overall design of a community-based multidisciplinary longitudinal study with the intent to stimulate interest and communication from scientists and practitioners studying the role of physical activity in preventive medicine. In adults, lack of regular exercise is a major risk factor in the development of chronic degenerative diseases and is a major contributor to obesity, and now we have evidence that many of our children are not sufficiently active to prevent early symptoms of chronic disease. The lifestyle of our kids (LOOK) study investigates how early physical activity contributes to health and development, utilizing a longitudinal design and a cohort of eight hundred and thirty 7-8-year-old (grade 2) school children followed to age 11-12 years (grade 6), their average family income being very close to that of Australia. We will test two hypotheses, that (a) the quantity and quality of physical activity undertaken by primary school children will influence their psychological and physical health and development; (b) compared with existing practices in primary schools, a physical education program administered by visiting specialists will enhance health and development, and lead to a more positive perception of physical activity. To test the first hypothesis we will monitor all children longitudinally over the 4 years. To test the second we will involve an intervention group of 430 children who receive two 50min physical education classes every week from visiting specialists and a control group of 400 who continue with their usual primary school physical education with their class-room teachers. At the end of grades 2, 4, and 6 we will measure several areas of health and development including blood risk factors for chronic disease, cardiovascular structure and function, physical fitness, psychological characteristics and perceptions of physical activity, bone structure and strength, motor control, body composition, nutritional intake, influence of teachers and family, and academic performance.
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Doença Crônica/prevenção & controle , Coleta de Dados/métodos , Exercício Físico/fisiologia , Promoção da Saúde/métodos , Atividade Motora/fisiologia , Projetos de Pesquisa , Adolescente , Austrália , Criança , Serviços de Saúde Comunitária/métodos , Ecocardiografia , Humanos , Estilo de Vida , Estudos Longitudinais , Aptidão Física/fisiologia , Aptidão Física/psicologia , Medicina Preventiva/métodos , Autoavaliação (Psicologia)RESUMO
OBJECTIVE: An age-dependent relationship between aortic and left ventricular (LV) stiffening has been observed in community-based adults. Our aim was to compare the performances of wave reflection-dependent (pulse pressure) and independent [carotid-femoral pulse wave velocity (PWV)] indexes of aortic stiffness to detect preclinical LV diastolic dysfunction. METHODS: In this case-control study, a stratified subsample of participants of a population-based echocardiographic survey with LV ejection fraction higher than 45% and without overt heart failure was randomly selected to undergo assessment of brachial blood pressure, LV diastolic function by Doppler echocardiography, and estimation of central aortic pressures and PWV by applanation tonometry. RESULTS: Of the 233 subjects (mean age 73 +/- 6 years, 54% men), 84 had normal diastolic function, 99 had mild diastolic dysfunction, and 50 had moderate or severe diastolic dysfunction. Brachial pulse pressure, central pulse pressure, and PWV progressively increased according to the severity of diastolic dysfunction, independent of age and sex. The overall performance of PWV was superior to brachial pulse pressure [area under receiver operating characteristic curve (AUC): 0.70 versus 0.59, respectively; P = 0.005] and central pulse pressure (AUC: 0.70 versus 0.56, respectively; P = 0.001) for the detection of any diastolic dysfunction. CONCLUSION: PWV appeared to be superior to central and brachial pulse pressure for the detection of diastolic dysfunction in older adults with 'preserved' LV ejection fraction.
Assuntos
Doenças da Aorta/diagnóstico , Velocidade do Fluxo Sanguíneo/fisiologia , Pressão Sanguínea/fisiologia , Fluxo Pulsátil/fisiologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Aorta/fisiologia , Doenças da Aorta/epidemiologia , Doenças da Aorta/fisiopatologia , Artérias Carótidas/fisiologia , Estudos de Casos e Controles , Diástole/fisiologia , Ecocardiografia Doppler , Feminino , Artéria Femoral/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Volume Sistólico/fisiologia , Disfunção Ventricular Esquerda/epidemiologia , Disfunção Ventricular Esquerda/fisiopatologiaRESUMO
We hypothesized that the magnitude of the association between plasma homocysteine concentration and cognitive performance is larger for ApoE-epsilon4 carriers than for non-carriers. Nine hundred eleven dementia-free and stroke-free subjects (59% women) from the Maine-Syracuse study (26-98 years old) were stratified into no-ApoE-epsilon4 (n=667) and ApoE-epsilon4 carrier (n=244) cohorts. Employing a cross-sectional design and multiple regression analyses, plasma homocysteine was related to multiple domains of cognitive performance within these cohorts. When unadjusted, and with adjustment for age, education, gender, ethnicity, and previous cognitive examinations, homocysteine concentrations were inversely related to cognitive performance within both ApoE cohorts, with higher magnitude of associations within the ApoE-epsilon4 cohort. With adjustment for cardiovascular disease risk factors, cardiovascular disease, and B-vitamin concentrations, the higher magnitude of associations between plasma homocysteine and cognitive performance within the ApoE-epsilon4 cohort relative to the no-ApoE-epsilon4 cohort persisted; but associations of plasma homocysteine and cognitive performance were attenuated and no longer significant within the no-ApoE-epsilon4 cohort. Presence of the ApoE-epsilon4 allele modifies the relation between plasma homocysteine and cognitive performance.
Assuntos
Apolipoproteína E4/genética , Cognição/fisiologia , Homocisteína/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Cardiovasculares/patologia , Estudos Transversais , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Fatores de Risco , Complexo Vitamínico B/sangueRESUMO
BACKGROUND: Previous studies have demonstrated a relationship between central adiposity and cognitive function. However, only some of these studies have adjusted for cardiovascular risk factors and cardiovascular disease, and none have also adjusted for physical activity level. PURPOSE: The purpose of the study was to examine the association between anthropometric measures of central adiposity (waist circumference and waist/hip ratio) and cognitive functioning with adjustment for cardiovascular disease risk factors and physical activity. METHODS: Participants were 917 stroke- and dementia-free community-dwelling adults (59% women) in the Maine-Syracuse Study. The design was cross-sectional. Outcome measures included tests from the Wechsler Adult Intelligence Scale, the Halstead-Reitan Neuropsychological Battery, the Wechsler Memory Scale Revised, and the Mini-Mental State Examination. RESULTS: Waist circumference and waist/hip ratio were inversely related to multiple cognitive domains with adjustment for age, education, gender, and number of prior exams. For example, a 20-cm increment in waist circumference was associated with a 0.14 SD decrement in the Global Composite score. These relations were attenuated with adjustment for cardiovascular disease risk factors. However, with further adjustment for physical activity level, only waist circumference remained significantly associated with performance on the Similarities test. CONCLUSIONS: Waist circumference and waist/hip ratio are inversely related to cognitive function. Measures of central adiposity predict cognitive function independently of associated cardiovascular risk factors and events; however, the association between central adiposity and cognitive function is attenuated, to a large extent, by adjustment for physical activity level. Physical activity is an important covariate in studies relating measures of central adiposity to cognition.
Assuntos
Gordura Abdominal , Adiposidade , Cognição , Relação Cintura-Quadril , Adulto , Idoso , Idoso de 80 Anos ou mais , Antropometria , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Intervalos de Confiança , Estudos Transversais , Feminino , Humanos , Modelos Logísticos , Maine , Masculino , Síndrome Metabólica/complicações , Pessoa de Meia-Idade , Atividade Motora , Fatores de RiscoRESUMO
BACKGROUND: Various charts based on body mass index (BMI) and per cent body fat (%BF) are used to classify childhood body composition but outcomes may vary. AIM: The study investigated variation in incidences of childhood obesity as depicted by four classification charts. SUBJECTS AND METHODS: BMI and DXA-derived %BF were assessed in 741 children. Incidences of overweight and obesity were compared between two BMI charts and two bioelectrical impedance (BIA)-based %BF charts. RESULTS: The International Obesity Task Force (IOTF)-adopted BMI chart designated 21%, 6% (boys), and 26%, 9% (girls) as overweight and obese, respectively. Corresponding figures using the USA CDC BMI chart were 27%, 11% (boys) and 27%, 12% (girls). Using a USA-derived %BF chart incidences were 17%, 2% (boys) and 21%, 8% (girls) and using a UK-derived %BF chart 51%, 24% (boys) and 53%, 36% (girls). Sensitivity of BMI varied according to the %BF reference chart. CONCLUSIONS: In contrast to the BMI-based charts, there were considerable variations in depicted incidences of obesity between the %BF-based charts. These discordances were considered to result from previously reported variation within and between BIA and DXA %BF assessments underlying the charts. The present study highlights the need for valid, reliable, unchanging BIA and DXA procedures.
Assuntos
Adiposidade , Índice de Massa Corporal , Obesidade/diagnóstico , Projetos de Pesquisa , Absorciometria de Fóton , Fatores Etários , Austrália/epidemiologia , Estatura , Criança , Impedância Elétrica , Feminino , Humanos , Masculino , Obesidade/epidemiologia , Padrões de Referência , Valores de Referência , Projetos de Pesquisa/normas , Sensibilidade e Especificidade , Fatores Sexuais , Estados UnidosRESUMO
OBJECTIVE: Our objective was to examine associations among plasma homocysteine concentrations (tHcy), the tHcy-cofactors (folate, vitamins B6 and B12), and multiple domains of cognitive performance, with statistical adjustment for possible confounds, including cardiovascular disease risk factors (CVD-RF) and cardiovascular disease (CVD). METHODS: Subjects were 812 participants (58% women) of the Maine-Syracuse study who were free of dementia and stroke. Employing a cross-sectional design and multiple regression analyses, fasting concentrations of tHcy and its vitamin cofactors (folate, B6, and B12) were related to multiple domains of cognitive performance. RESULTS: With adjustment for age, education, gender, ethnicity, and the vitamins, tHcy was inversely associated with visual-spatial organization, working memory, scanning-tracking, and abstract reasoning. The same results were found with adjustment for age, education, gender, ethnicity, CVD-RF, and CVD. Vitamin cofactors were positively related to cognitive performance, but with adjustment for CVD-RF and CVD, only vitamin B6 was related to multiple cognitive domains. CONCLUSIONS: The inverse association of tHcy with multiple domains of cognitive functioning is not necessarily dependent on vitamin levels, vitamin deficiency, prevalent CVD risk factors, and manifest CVD. Serum folate, serum B12, and plasma B6 vitamin concentrations are positively associated with cognitive performance. Investigation of other possible mechanisms (e.g., tHcy neurotoxicity) mediating tHcy associations with cognitive performance is important, as are clinical trials examining the efficacy of folate, vitamin B6, and vitamin B12 for maintenance of cognitive functioning.
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Transtornos Cognitivos/sangue , Transtornos Cognitivos/diagnóstico , Ácido Fólico/sangue , Homocisteína/sangue , Testes Neuropsicológicos/estatística & dados numéricos , Vitamina B 12/sangue , Vitamina B 6/sangue , Fatores Etários , Deficiência de Vitaminas/diagnóstico , Deficiência de Vitaminas/epidemiologia , Doenças Cardiovasculares/epidemiologia , Estudos Transversais , Escolaridade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores SexuaisRESUMO
To determine whether abnormalities in heart rate (HR) were associated with long-term mortality in older, low-level care residents, 179 randomly selected persons aged 65 and older (mean, 83.2+/-7.0 [SD] years; 80% women) were prospectively assessed. At baseline, duplicate measurements of HR and blood pressure were recorded in the supine position and after standing. During the 5-year follow-up period, 97 (54%) participants died. Cox survival analysis revealed no association with total mortality when resting HR was analyzed as a continuous or categoric variable (< or = 60, 61-89, and > 90 bpm). However, HR > or = 90 bpm was associated with increased risk of dying in residents who used a walking aid (relative risk, 3.48; 95% confidence interval, 1.07-11.30; p=0.038). Postural HR change was not associated with mortality risk. The authors concluded that resting HR and postural change in HR are not significant predictors of 5-year mortality in older, low-level care residents, except in persons using a walking aid.
Assuntos
Frequência Cardíaca , Mortalidade , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Assistência de Longa Duração , Masculino , Equipamentos Ortopédicos , Postura/fisiologia , Modelos de Riscos Proporcionais , Instituições Residenciais , Análise de SobrevidaRESUMO
AIM: To investigate doctors' response to and understanding of the legal status of advance directives. METHODS: A vignette-based study administered at palliative medicine, oncology, general practice, and geriatric medicine specialist registrar meetings (United Kingdom). Respondents determined the treatment to provide for a patient presenting with a myocardial infarction with or without an advance directive requesting maximum therapy. RESULTS: Response rate 77% (43/56). Twenty-five percent (10/40) of respondents increased the care that they would provide in response to the advance directive (p = 0.004); 77% (33/43) support/strongly support use of advance directives; 51% (22/43) did not know the legal status of advance directives; 44% found that their medical school education was not an important influence on their decision making. CONCLUSIONS: Advance directives requesting treatment can increase the level of care provided by the physician, however, most trainees chose a level of care different from that in the advance directive. Confusion exists among doctors about the legal status of advance directives, which limits their usefulness. Medical education needs to be improved to train doctors to deal with advance directives.
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Adesão a Diretivas Antecipadas/normas , Diretivas Antecipadas , Atitude do Pessoal de Saúde , Conhecimentos, Atitudes e Prática em Saúde , Corpo Clínico , Adesão a Diretivas Antecipadas/legislação & jurisprudência , Diretivas Antecipadas/legislação & jurisprudência , Doença de Alzheimer/complicações , Competência Clínica/normas , Compreensão , Cuidados Críticos/organização & administração , Currículo/normas , Tomada de Decisões , Educação de Pós-Graduação em Medicina , Inglaterra , Medicina de Família e Comunidade/educação , Geriatria/educação , Necessidades e Demandas de Serviços de Saúde , Humanos , Oncologia/educação , Corpo Clínico/educação , Corpo Clínico/psicologia , Competência Mental , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/terapia , Cuidados Paliativos/organização & administração , Seleção de Pacientes , Estatísticas não Paramétricas , Inquéritos e QuestionáriosRESUMO
OBJECTIVE: The primary purpose of this study was to examine associations between indices of blood pressure (BP) and cognitive function for African-American participants in the Maine-Syracuse Longitudinal Study (MSLS). Corresponding data for the Caucasian-American MSLS participants were included to provide a basis for comparison. Interactions of age with BP indices were also assessed in relation to cognitive function. METHODS: Data were drawn from the baseline MSLS questionnaires, medical interviews and examinations, Wechsler Adult Intelligence Scale subtests, and measurements of BP for 1563 participants, of whom 147 were African American. Multiple linear regression analyses were employed to examine the relationship between several BP predictors and cognitive outcomes with statistical adjustment for demographic, psychosocial, and cardiovascular risk factors. RESULTS: Significant inverse associations between BP indices and cognitive performance were obtained for both racial cohorts but were generally of higher magnitude for the African-American cohort. Interactions of BP with age were not obtained for any of the cognitive test scores. CONCLUSIONS: Elevations in BP are associated with poorer cognitive function for African-American and Caucasian-American cohorts. These associations are similar for younger and older participants.
Assuntos
Negro ou Afro-Americano/estatística & dados numéricos , Transtornos Cognitivos/epidemiologia , Hipertensão/epidemiologia , Testes Neuropsicológicos/estatística & dados numéricos , População Branca/estatística & dados numéricos , Adolescente , Adulto , Distribuição por Idade , Fatores Etários , Idoso , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/fisiologia , Cognição/fisiologia , Transtornos Cognitivos/diagnóstico , Estudos de Coortes , Comorbidade , Feminino , Humanos , Hipertensão/diagnóstico , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Prevalência , Escalas de WechslerRESUMO
OBJECTIVES: To evaluate which indices of blood pressure (BP) homeostasis are the strongest predictors of mortality in older low-level-care residents in long-term health facilities. DESIGN: Prospective cohort study. SETTING: Eight long-term healthcare facilities in Canberra, Australia. PARTICIPANTS: A total of 179 randomly selected semi-independent residents aged 65 and older (mean age+/-standard deviation 83.2+/-7.0; 80% women). MEASUREMENTS: Baseline BP levels taken while lying, after standing for 1 and 3 minutes, and sitting before and 1 hour after meal intake were recorded, as well as demographic information, chronic medical conditions, medications, and all-cause mortality during follow-up. Postprandial hypotension (PPH) was defined as a fall in systolic BP (SBP) of 20 mmHg or more 1 hour postmeal while sitting. Orthostatic hypotension (OH) was defined as a fall in SBP of 20 mmHg or more or in diastolic BP (DBP) of 10 mmHg or more within 3 minutes of standing from a supine position. Hypertension was defined as BP greater than 160/90 mmHg at commencement of the study. Mean arterial pressure (MAP) and pulse pressure (PP) were calculated. RESULTS: At baseline, 47% of participants had hypertension, 38% PPH, and 23% OH; PP was 70 mmHg or greater in 54%, and DBP was 65 mmHg or lower in 6%. Over 4.7 years, 97 (54%) participants died. Those who died were significantly older and more likely to have PPH (47% vs 28%) and atrial fibrillation (35% vs 17%) and a significantly greater decrease in BP after meal intake. Mortality rates in those with and without PPH were 145.0 and 98.5 per 1,000 person-years, respectively. Using multivariate Cox proportional hazards models after adjustment for age, sex, presence of atrial fibrillation, Parkinson's disease, and use of diuretics, PPH was the only BP parameter that significantly and independently predicted 4.7-year all-cause mortality (relative risk (RR)=1.79; 95% confidence interval (CI)=1.19-2.68; P=.005). Further adjustment for the presence of OH, hypertension, low resting BP, coronary artery disease, cerebrovascular disease, congestive heart failure, history of syncope, cognitive impairment, cancer, diabetes mellitus, chronic obstructive pulmonary disease, and history of smoking did not reveal any new statistically significant associations. There was a dose-response relationship between postprandial fall in SBP and mortality rates. Absolute postprandial SBP of 120 mmHg or less was also significantly associated with total mortality (RR=1.69, 95% CI=1.04-2.78; P=.04). Low DBP was also associated with increased mortality (RR=1.10, 95% CI=1.01-1.13; P=.03), although this association became nonsignificant in multivariate analysis. CONCLUSION: In older low-level-care residents, PPH is an independent predictor of all-cause mortality with no added predictive value explained by other BP indices: OH, hypertension, PP, MAP.
Assuntos
Pressão Sanguínea/fisiologia , Ingestão de Alimentos/fisiologia , Homeostase/fisiologia , Mortalidade , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/complicações , Estudos de Coortes , Feminino , Humanos , Hipertensão/complicações , Masculino , Análise Multivariada , Doença de Parkinson/complicações , Prognóstico , Estudos ProspectivosRESUMO
This study assessed the management of delirium in the Acute Care of the Elderly unit (ACE) at a tertiary referral hospital as a case study of the application of clinical governance principles. The environment was found to be supportive of ongoing clinical governance activities, both in clinical organisation of work processes and orientation of management. However, patient involvement, dissemination and use of clinical pathways, performance measurement and feedback, and maintaining stability of care are areas requiring further development. Although there is a clinical governance strategy in place at the policy level, this has not always filtered through to the level of clinical work.
Assuntos
Delírio/tratamento farmacológico , Garantia da Qualidade dos Cuidados de Saúde/organização & administração , Idoso de 80 Anos ou mais , Território da Capital Australiana , Feminino , Hospitais de Ensino , Humanos , Masculino , Auditoria Médica , Estudos de Casos OrganizacionaisRESUMO
OBJECTIVES: To investigate the relationship between total plasma homocysteine (tHcy) levels, blood pressure (BP) variables, renal function, and measures of cognitive performance in older people. DESIGN: Initial cross-sectional analysis of a prospective cohort. SETTING: United Kingdom (Oxfordshire) community sample. PARTICIPANTS: One hundred fifty-eight community-dwelling volunteers aged 60 to 91. MEASUREMENTS: Neuropsychological tests (Cambridge Examination for Mental Disorders of the Elderly-Cognitive Section (CAMCOG), Mini-Mental State Examination (MMSE), and Geriatric Depression Scale), biochemical studies (tHcy, serum folate, vitamin B12, and serum cystatin C), BP, and other vascular risk factors. RESULTS: tHcy, age, systolic BP (SBP), and CAMCOG performance were significantly interrelated. tHcy was negatively associated with total CAMCOG score independent of years of education, serum folate, vitamin B12, and cystatin C levels. Older participants with higher tHcy levels had lower CAMCOG scores-especially men aged 70 and older. Higher tHcy levels were associated with poorer performance on the memory and perception subscores of CAMCOG but not with the other cognitive subscales or MMSE score. SBP also demonstrated a significant negative association with total CAMCOG and MMSE scores. CONCLUSIONS: These results suggest independent associations between tHcy (modified by age and sex) and SBP and cognitive performance in older people. Further longitudinal study will define whether optimization of tHcy and systolic BP contributes to the maintenance of cognitive performance with successful aging.
Assuntos
Idoso/fisiologia , Pressão Sanguínea/fisiologia , Cognição/fisiologia , Homocisteína/sangue , Fatores Etários , Idoso de 80 Anos ou mais , Feminino , Humanos , Testes de Inteligência , Masculino , Memória , Pessoa de Meia-Idade , Testes Neuropsicológicos , Percepção , Estudos Prospectivos , Fatores SexuaisRESUMO
We hypothesized that carotid-femoral pulse wave velocity (PWV), a marker of arterial stiffness, interacts with age such that the magnitude of associations between PWV and cognitive performance are greater with increasing age and that this interaction is observed despite adjustments for demographic variables, mean arterial pressure, and cardiovascular risk factors. PWV was estimated using applanation tonometry in 409 dementia- and stroke-free participants of the Maine-Syracuse Longitudinal Study (24 to 92 years of age; 62.3% women). Using linear regression analyses in a cross-sectional design, associations between PWV and age and the interaction of PWV and age were examined in relation to a global composite score, the Wechsler Adult Intelligence Scale Similarities test (abstract reasoning), and 4 cognitive domains indexed by multiple cognitive measures. Adjusting for age, gender, education, height, weight, heart rate, mean arterial pressure, and antihypertensive treatment, PWV-by-age interactions were obtained for the global, visual-spatial organization and memory, scanning and tracking, and verbal episodic memory composites, as well as similarities. The combination of higher PWV and age resulted in progressively lower cognitive performance. This finding was the same with an extended model, which also included adjustment for cardiovascular risk factors and other confounds. PWV interacts with age in a multiplicative way to exert a negative influence on cognitive performance level. Early interventions to prevent an increase in arterial stiffness could possibly play an important role in the preservation of cognitive ability.
Assuntos
Envelhecimento/fisiologia , Velocidade do Fluxo Sanguíneo/fisiologia , Transtornos Cognitivos/fisiopatologia , Hipertensão/fisiopatologia , Fluxo Pulsátil/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea/fisiologia , Artérias Carótidas/fisiologia , Cognição/fisiologia , Transtornos Cognitivos/epidemiologia , Estudos Transversais , Feminino , Artéria Femoral/fisiologia , Humanos , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Fatores de Risco , Escalas de Wechsler , Adulto JovemRESUMO
Childhood obesity is increasingly prevalent in the community and is related to adverse cardiovascular outcomes during adulthood. In this study of healthy children, we evaluated the influence of adiposity and physical activity on carotid-femoral pulse wave velocity (PWV), an index of arterial stiffness and a marker of cardiovascular risk in adults. In 573 community-based children (mean age: 10.1+/-0.3 years; 51% boys), we measured body mass index and waist circumference. Percentage body fat was quantitated by dual-energy x-ray absorptiometry. Cardiorespiratory fitness (CRF) and physical activity levels were assessed using a 20-m shuttle run and 7-day pedometer count, respectively. PWV was estimated by applanation tonometry. In univariate analysis, PWV was positively correlated with body mass index (r=0.34), waist circumference (r=0.32), and percentage body fat (r=0.32; P<0.001 for all) and negatively correlated with CRF (r=-0.23; P<0.001) and pedometer count (r=-0.08; P=0.046). In separate multivariable linear regression models, body mass index, waist circumference, and percentage of body fat were independently and positively associated with PWV (P<0.01 for all) after adjusting for age, sex, systolic blood pressure, mean arterial pressure, heart rate, and CRF (P<0.01 for all). The influence of CRF on PWV was attenuated after adjusting for adiposity. In conclusion, increased body mass and adiposity and decreased CRF are associated with arterial stiffening in healthy prepubescent children.
Assuntos
Hipertensão/epidemiologia , Hipertensão/fisiopatologia , Estilo de Vida , Atividade Motora , Obesidade/epidemiologia , Obesidade/fisiopatologia , Tecido Adiposo , Velocidade do Fluxo Sanguíneo/fisiologia , Índice de Massa Corporal , Artérias Carótidas/fisiologia , Criança , Venenos de Crotalídeos , Feminino , Artéria Femoral/fisiologia , Frequência Cardíaca , Humanos , Estudos Longitudinais , Masculino , Análise Multivariada , Obesidade/patologia , Prevalência , Fluxo Pulsátil/fisiologia , Ácido Pirrolidonocarboxílico/análogos & derivados , Fatores de Risco , Circunferência da CinturaRESUMO
We describe a distributed falls management system capable of real-time falls detection in an unsupervised living context and remote longitudinal tracking of falls risk parameters using a waist-mounted triaxial accelerometer. A self-administrable falls risk assessment is used to facilitate falls prevention. A web-interface allows clinicians to monitor the status of individuals and track their compliance with exercise interventions. Early identification of increased falls risk allows targeted interventions to be promptly administered. Real-time detection of falls allows immediate emergency response protocols to be deployed, reducing morbidity and increasing the independence of the community-dwelling elderly community.
Assuntos
Acidentes por Quedas/prevenção & controle , Instituição de Longa Permanência para Idosos , Telemetria/instrumentação , Telemetria/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , MasculinoRESUMO
In model-based segmentation, automated region identification is achieved via registration of novel data to a pre-determined model. The desired structure is typically generated via manual tracing within this model. When model-based segmentation is applied to human cortical data, problems arise if left-right comparisons are desired. The asymmetry of the human cortex requires that both left and right models of a structure be composed in order to effectively segment the desired structures. Paradoxically, defining a model in both hemi-spheres carries a likelihood of introducing bias to one of the structures. This paper describes a novel technique for creating a symmetric average model in which both hemispheres are equally represented and thus left-right comparison is possible. This work is an extension of that proposed by Guimond et al. Hippocampal segmentation is used as a test-case in a cohort of 118 normal eld-erly subjects and results are compared with expert manual tracing.
Assuntos
Algoritmos , Inteligência Artificial , Hipocampo/anatomia & histologia , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Reconhecimento Automatizado de Padrão/métodos , Idoso , Idoso de 80 Anos ou mais , Anatomia Artística/métodos , Simulação por Computador , Humanos , Ilustração Médica , Pessoa de Meia-Idade , Modelos Neurológicos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
This study aimed to address the criteria and the stability of the classification of MCI. The Foresight Challenge cohort of 157 community-dwelling volunteers was assessed on 3 visits at 2-year intervals with episodic, semantic and working memory tests. Subjective memory complaints were assessed with the CAMDEX. Of the cohort, 2% had dementia and 31% were classified with MCI at visit 3, 43% with stable impairment from Time 1. Thirteen percent of those with objective memory impairment at Time 1 or 2 improved to control status by Time 3. Episodic memory tests were predictive for MCI at all timepoints, as were tests for praxis and Graded Naming, while at Time 3 spatial span lost predictive value, but processing speed became predictive. Decline in processing speed was seen in control and MCI groups, while memory performance and MMSE decline occurred only in the MCI group. The use of combined memory test scores gave better sensitivity to MCI than single tests. Subjective memory complaints were positive for 79% of the MCI group and 62.5% of controls. These findings would suggest consideration of modification of current MCI criteria.
Assuntos
Transtornos Cognitivos , Memória/fisiologia , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Transtornos Cognitivos/classificação , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/fisiopatologia , Estudos de Coortes , Demografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Valor Preditivo dos Testes , Escalas de Graduação Psiquiátrica , Reprodutibilidade dos Testes , Semântica , Sensibilidade e Especificidade , Fatores de TempoRESUMO
OBJECTIVE: Authors performed a neuropsychological determination of which individuals in a group of community-dwelling, healthy elderly volunteers would develop cognitive decline. METHODS: A group of 155 volunteers reporting good memory and thinking participated in a prospective study over 4 years. Authors monitored cognitive functioning and incidence of Mild Cognitive Impairment (MCI)/Alzheimer disease (AD). RESULTS: Baseline assessment revealed a subgroup of participants with deficits in associative learning and naming; subsequent cognitive decline was more precipitous in these individuals, who also showed higher relative risk of MCI/AD. CONCLUSION: Cognitive measures may be useful in community and clinical dementia screening and applicable for identifying enriched samples for trials of anti-dementia treatments.