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BACKGROUND There is no single generally accepted clinical definition of frailty. Previously developed tools to assess frailty that have been shown to be predictive of death or need for entry into an institutional facility have not gained acceptance among practising clinicians. We aimed to develop a tool that would be both predictive and easy to use. (More)
Recent research has demonstrated that brain circulation abnormalities, either during task-induced neural activity or at rest, are more commonly associated with Alzheimer's disease (AD) than was previously thought. This is consistent with the increasing attention to the early involvement of vascular risk factors in the development of AD, in addition to the(More)
Alzheimer's disease (AD) affects several important molecules in brain metabolism. The resulting neurochemical changes can be quantified non-invasively in localized brain regions using in vivo single-voxel proton magnetic resonance spectroscopy (SV 1H MRS). Although the often heralded diagnostic potential of MRS in AD largely remains unfulfilled, more recent(More)
BACKGROUND While on average health declines with age, it also becomes more variable with age. As a consequence of this marked variability, it becomes more important as people age to have a means of summarizing health status, but how precisely to do so remains controversial. We developed one measure of health status, personal biological age, from a frailty(More)
OBJECTIVES To investigate the relationship between accumulated health-related problems (deficits), which define a frailty index in older adults, and mortality in population-based and clinical/institutional-based samples. DESIGN Cross-sectional and cohort studies. SETTING Seven population-based and four clinical/institutional surveys in four developed(More)
OBJECTIVES To evaluate the potential of an artificial neural network (ANN) in predicting survival in elderly Canadians, using self-report data. DESIGN Cohort study with up to 72 months follow-up. SETTING Forty self-reported characteristics were obtained from the community sample of the Canadian Study of Health and Aging. An individual frailty index(More)
OBJECTIVES To measure relative fitness and frailty in older people without specific frailty instruments and to relate that measurement to long-term health outcomes. DESIGN Retrospective cohort studies. SETTING Two population-based studies of people aged approximately 70 at baseline and followed up to 10 years (in the Canadian Study of Health and Aging(More)
The health of individuals is highly heterogeneous, as is the rate at which they age. To account for such heterogeneity, we have suggested that an individual’s health status can be represented by the number of health deficits (broadly defined by biological and clinical characteristics) that they accumulate. This allows health to be expressed in a single(More)
Several machine learning techniques (multilayer and single layer perceptron, logistic regression, least square linear separation and support vector machines) are applied to calculate the risk of death from two biomedical data sets, one from patient care records, and another from a population survey. Each dataset contained multiple sources of information:(More)
BACKGROUND This study investigates how T(1)-weighted MRI can be used to evaluate brain anatomical changes. We investigated these changes in Alzheimer's disease (AD) and normal aging. METHODS A semiquantitative brain atrophy and lesion index (BALI) was constructed by adapting existing visual rating scales and validated in 3 datasets. RESULTS The T(1)-(More)