Villemagne V.L.,Austin Health |
Villemagne V.L.,University of Melbourne |
Burnham S.,CSIRO |
Bourgeat P.,CSIRO |
And 12 more authors.
The Lancet Neurology | Year: 2013
Background: Similar to most chronic diseases, Alzheimer's disease (AD) develops slowly from a preclinical phase into a fully expressed clinical syndrome. We aimed to use longitudinal data to calculate the rates of amyloid β (Aβ) deposition, cerebral atrophy, and cognitive decline. Methods: In this prospective cohort study, healthy controls, patients with mild cognitive impairment (MCI), and patients with AD were assessed at enrolment and every 18 months. At every visit, participants underwent neuropsychological examination, MRI, and a carbon-11-labelled Pittsburgh compound B (11C-PiB) PET scan. We included participants with three or more 11C-PiB PET follow-up assessments. Aβ burden was expressed as 11C-PiB standardised uptake value ratio (SUVR) with the cerebellar cortex as reference region. An SUVR of 1·5 was used to discriminate high from low Aβ burdens. The slope of the regression plots over 3-5 years was used to estimate rates of change for Aβ deposition, MRI volumetrics, and cognition. We included those participants with a positive rate of Aβ deposition to calculate the trajectory of each variable over time. Findings: 200 participants (145 healthy controls, 36 participants with MCI, and 19 participants with AD) were assessed at enrolment and every 18 months for a mean follow-up of 3·8 (95% CI CI 3·6-3·9) years. At baseline, significantly higher Aβ burdens were noted in patients with AD (2·27, SD 0·43) and those with MCI (1·94, 0·64) than in healthy controls (1·38, 0·39). At follow-up, 163 (82%) of the 200 participants showed positive rates of Aβ accumulation. Aβ deposition was estimated to take 19·2 (95% CI 16·8-22·5) years in an almost linear fashion-with a mean increase of 0·043 (95% CI 0·037-0·049) SUVR per year-to go from the threshold of 11C-PiB positivity (1·5 SUVR) to the levels observed in AD. It was estimated to take 12·0 (95% CI 10·1-14·9) years from the levels observed in healthy controls with low Aβ deposition (1·2 [SD 0·1] SUVR) to the threshold of 11C-PiB positivity. As AD progressed, the rate of Aβ deposition slowed towards a plateau. Our projections suggest a prolonged preclinical phase of AD in which Aβ deposition reaches our threshold of positivity at 17·0 (95% CI 14·9-19·9) years, hippocampal atrophy at 4·2 (3·6-5·1) years, and memory impairment at 3·3 (2·5-4·5) years before the onset of dementia (clinical dementia rating score 1). Interpretation: Aβ deposition is slow and protracted, likely to extend for more than two decades. Such predictions of the rate of preclinical changes and the onset of the clinical phase of AD will facilitate the design and timing of therapeutic interventions aimed at modifying the course of this illness. Funding: Science and Industry Endowment Fund (Australia), The Commonwealth Scientific and Industrial Research Organisation (Australia), The National Health and Medical Research Council of Australia Program and Project Grants, the Austin Hospital Medical Research Foundation, Victorian State Government, The Alzheimer's Drug Discovery Foundation, and the Alzheimer's Association. © 2013 Elsevier Ltd.
Borland R.,VicHealth Center for Tobacco Control |
Savvas S.,National Ageing Research Institute
Tobacco Control | Year: 2013
Objective To examine the extent (if any) that cigarette stick dimension, tipping paper design and other decorative design/branding have on Australian smokers' perceptions of those cigarettes. Methods An internet survey of 160 young Australian adult ever-smokers who were shown computer images of three sets of cigarette sticksdfive sticks of different lengths and diameters (set A), five sticks with different tipping paper design (set B) and four sticks of different decorative design (set C). Branding was a between-subjects randomised condition for set C. For each set, respondents ranked sticks on most and least attractive, highest and lowest quality and strongest and weakest taste. Results Cigarette sticks were perceived as different on attractiveness, quality and strength of taste. Standard stick length/diameter was perceived as the most attractive and highest quality stick, with men more inclined to rate a slim stick as less attractive. A stick with a cork-patterned tipping paper and a gold band was seen as most attractive, of highest quality and strongest in taste compared to other tipping designs. Branded sticks were seen as more attractive, higher in quality and stronger tasting than non-branded designs, regardless of brand, although the effects were stronger for a prestige compared with a budget brand. Conclusions Characteristics of the cigarette stick affect smokers' perceptions of the attributes of those cigarettes and thus are a potential means by which product differentiation can occur. A comprehensive policy to eliminate promotional aspects of cigarette design and packaging needs to include rules about stick design.
Brodaty H.,University of New South Wales |
Connors M.H.,University of New South Wales |
Xu J.,University of New South Wales |
Woodward M.,University of Melbourne |
And 2 more authors.
Journal of Alzheimer's Disease | Year: 2014
Patients with dementia often require institutionalization when they can no longer care for themselves. The study examined demographic and clinical variables that predict the time until institutionalization in patients with dementia attending memory clinics. Of 970 patients recruited from nine memory clinics around Australia, 779 patients had dementia at baseline. Measures of dementia severity, cognition, functional ability, neuropsychiatric symptoms, caregiver burden, and medication use were completed for all patients. Patients were followed for three years. Overall, 197 (25.3%) of the patients with dementia were institutionalized within three years. Lower cognitive ability, lower functional ability, and more neuropsychiatric symptoms at baseline predicted a shorter time until institutionalization, as did use of antipsychotic medication. In addition, greater deterioration in cognitive ability, functional ability, and neuropsychiatric symptoms over the initial three months predicted a shorter time to institutionalization. The findings confirm that clinical features of dementia at baseline predict the time to institutionalization, as do greater changes in symptoms over three months independent of baseline levels. © 2014 - IOS Press and the authors. All rights reserved.
Hadjistavropoulos T.,University of Regina |
Herr K.,University of Iowa |
Prkachin K.M.,University of Northern British Columbia |
Craig K.D.,University of British Columbia |
And 3 more authors.
The Lancet Neurology | Year: 2014
Chronic pain is highly prevalent in the ageing population. Individuals with neurological disorders such as dementia are susceptible patient groups in which pain is frequently under-recognised, underestimated, and undertreated. Results from neurophysiological and neuroimaging studies showing that elderly adults are particularly susceptible to the negative effects of pain are of additional concern. The inability to successfully communicate pain in severe dementia is a major barrier to effective treatment. The systematic study of facial expressions through a computerised system has identified core features that are highly specific to the experience of pain, with potential future effects on assessment practices in people with dementia. Various observational-behavioural pain assessment instruments have been reported to be both reliable and valid in individuals with dementia. These techniques need to be interpreted in the context of observer bias, contextual variables, and the overall state of the individual's health and wellbeing. © 2014 Elsevier Ltd.
Mental Health Research Institute, Csiro, National Ageing Research Institute and Edith Cowan University | Date: 2012-05-03
The present invention provides methods for predicting whether a subject will develop a disease capable of affecting cognitive function. More specifically, the present invention relates to the predictive detection of neurological diseases in a subject. The methods and systems provided enable a quantitative assessment and theoretical predictions of neocortical amyloid loading or amyloid beta levels based on the measurement of biomarkers in biological fluids that will provide an indication of whether a subject is likely to develop a neurological disease, such as Alzheimers disease (AD).
Lautenschlager N.T.,University of Melbourne |
Lautenschlager N.T.,University of Western Australia |
Cox K.,University of Western Australia |
Cyarto E.V.,National Ageing Research Institute
Biochimica et Biophysica Acta - Molecular Basis of Disease | Year: 2012
Physical activity has been recognized as an important protective factor reducing disability and mortality and therefore it is focus of many health promotion activities at all ages. More recently a growing body of literature is focusing whether physical activity could also have a positive impact on brain aging with exploring healthy brain aging as well as on cognitive impairment and dementia. An increasing number of prospective studies and randomized controlled trials involving humans take place both with older adults with normal cognition as well as with mild cognitive impairment or dementia. However, the body of evidence is still sparse and many methodological issues make comparisons across studies challenging. Increasingly research into underlying mechanisms in relation to physical activity and brain aging identify biomarker candidates with especially neuroimaging measurements being more used in trials with humans. Whilst the evidence base is slowly growing more detailed research is needed to address methodological issues to finally achieve clinical relevance. This article is part of a Special Issue entitled: Imaging Brain Aging and Neurodegenerative disease. © 2011.
Anpalahan M.,Western Hospital |
Gibson S.,National Ageing Research Institute
European Journal of Internal Medicine | Year: 2012
Aims: To determine the prevalence and clinical significance of carotid sinus syndrome (CSS) and vasovagal syncope (VVS), the two common types of Neurally Mediated Syncope (NMS), in a cohort of older patients with unexplained falls. Methods: Patients presenting with unexplained and accidental falls were identified from 200 consecutive admissions of falls in patients aged 65 years and older admitted to the Rapid Assessment Medical Unit (RAMU) in a teaching hospital. A sample of unexplained and accidental fallers underwent carotid sinus massage (CSM) and tilt table testing (TTT) as per a standardised protocol. Baseline characteristics, clinical variables and the prevalence of NMS were compared between the two groups. Results: Falls were unexplained in 26% of patients. The prevalence of NMS was 24% (5/21) among patients with unexplained falls who underwent assessment for NMS, whereas it was nil (0/17) in patients with accidental falls (P = 0.050). The prevalence of previous falls was significantly higher in patients with unexplained falls (P = 0.0025), but all other baseline characteristics were similar between the two groups. Conclusion: Falls are unexplained in a significant number of older patients presenting to acute hospitals. The assessment of unexplained fallers for NMS is clinically important as this may be aetiologically related in nearly a quarter of these patients. © 2011 European Federation of Internal Medicine.
Biggs S.,University of Melbourne |
Haapala I.,University of Eastern Finland |
Haapala I.,National Ageing Research Institute
International Psychogeriatrics | Year: 2013
Background: Elder mistreatment, social ageism, and human rights are increasingly powerful discourses in positioning older people in society, ye. The relationship between them has rarely been subjected to critical investigation. This perceived relationship will have implications for how mistreatment is understood and responded to. Method: Critical gerontological approach based on narrative and textual analysis. Results: Reports of public attitudes toward mistreatment suggest that it is thought to be more common than scientific evidence would suggest; however, reporting is much lower than prevalence. Whil. The discourse over mistreatment has tended to focus on interpersonal relationships, ageism has emphasized social attitudes, and human rights have concentrated on relations betwee. The state an. The individual. Conclusions: In this paper, a series of models have been examined which mark a tendency to restrict and then attempt to reintegrate individual, interpersonal, and social levels of analysis. It is concluded that a focus o. The processes of transaction across boundaries rather than contents would facilitate both integrative modeling and deeper understanding o. The qualities of abusive situations. © 2013 International Psychogeriatric Association.
You E.C.,University of Melbourne |
Dunt D.R.,University of Melbourne |
Doyle C.,National Ageing Research Institute |
Doyle C.,Australian Catholic University
Journal of Aging and Health | Year: 2013
Objective: To evaluate the effects of case management in community aged care (CMCAC) interventions on service use and costs. Method: Five databases were searched from inception to 2011 July to include randomized control trials and comparative observational English studies. Results were summarized by using the best-evidence synthesis approach. Results: Twenty-one studies were included. Available studies supported improvements in clients' use of case management services (all of the four studies), some community services (8 of the 10) and nursing home admission and stay (around one half), delay of nursing home placement (all of the two studies), and achieving cost neutrality (8 of the 11). The effects on medical care utilization were varying. Discussion: In general, these positive effects justify the further development and refinement of CMCAC programs. Result applicability is limited by only including English studies. Cost studies applying a societal perspective, and full economic appraisals where appropriate are warranted. © 2013 The Author(s).
Chua C.K.Z.,University of Melbourne |
Henderson V.W.,Stanford University |
Dennerstein L.,University of Melbourne |
Ames D.,National Ageing Research Institute |
Szoeke C.,University of Melbourne
Neurobiology of Aging | Year: 2014
The association between serum dehydroepiandrosterone sulfate (DHEAS) and cognition was assessed in 218 healthy, midlife, post-menopausal women, aged 55-65years. In cross-sectional analyses, DHEAS level was not significantly associated with a standardized score of global cognition or with individual test scores from a comprehensive neuropsychological battery (all p-values >0.05). In longitudinal analyses of 176 women, DHEAS level was unassociated with cognition 2years later or with 2-year change in cognition. These findings fail to support the view that DHEAS is substantially related to cognitive function in midlife, post-menopausal women. © 2014 Elsevier Inc.