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Summary: Isolated rapid eye movement (REM) sleep behaviour disorder (iRBD) is a sleep disorder that is characterised by dream enactment episodes during REM sleep. It is the strongest known predictor of α‐synuclein‐related neurodegenerative disease (αNDD), such that >80% of people with iRBD will eventually develop Parkinson's disease, dementia with Lewy bodies, or multiple system atrophy in later life. More research is needed to understand the trajectory of phenoconversion to each αNDD. Only five 'gold standard' prevalence studies of iRBD in older adults have been undertaken previously, with estimates ranging from 0.74% to 2.01%. The diagnostic recommendations for video‐polysomnography (vPSG) to confirm iRBD makes prevalence studies challenging, as vPSG is often unavailable to large cohorts. In Australia, there have been no iRBD prevalence studies, and little is known about the cognitive and motor profiles of Australian people with iRBD. The Island Study Linking Ageing and Neurodegenerative Disease (ISLAND) Sleep Study will investigate the prevalence of iRBD in Tasmania, an island state of Australia, using validated questionnaires and home‐based vPSG. It will also explore several cognitive, motor, olfactory, autonomic, visual, tactile, and sleep profiles in people with iRBD to better understand which characteristics influence the progression of iRBD to αNDD. This paper details the ISLAND Sleep Study protocol and presents preliminary baseline results. [ABSTRACT FROM AUTHOR]

Background: Unmanaged cardiometabolic health, low physical and cognitive activity, poor diet, obesity, smoking and excessive alcohol consumption are modifiable health risk factors for dementia and public health approaches to dementia prevention have been called for. The Island Study Linking Ageing and Neurodegenerative Disease (ISLAND) is a dementia prevention public health study examining whether improving knowledge about modifiable dementia risk factors supports behaviour changes that reduce future dementia risk. Methods: Residents of Tasmania, Australia, aged 50 + years who joined the 10-year ISLAND study were asked to complete annual online surveys about their knowledge, motivations and behaviours related to modifiable dementia risk. ISLAND included two knowledge-based interventions: a personalised Dementia Risk Profile (DRP) report based on survey responses, and the option to do a 4-week Preventing Dementia Massive Open Online Course (PDMOOC). Longitudinal regression models assessed changes in the number and type of risk factors, with effects moderated by exposures to the DRP report and engagement with the PDMOOC. Knowledge and motivational factors related to dementia risk were examined as mediators of risk behaviour change. Results: Data collected between October 2019 and October 2022 (n = 3038, av. 63.7 years, 71.6% female) showed the mean number of modifiable dementia risk factors per participant (range 0 to 9) reduced from 2.17 (SD 1.24) to 1.66 (SD 1.11). This change was associated with the number of exposures to the DRP report (p =.042) and was stronger for PDMOOC participants (p =.001). The interaction between DRP and PDMOOC exposures yielded a significant improvement in risk scores (p =.004). The effect of PDMOOC engagement on behaviour change was partly mediated by increased knowledge (12%, p =.013). Self-efficacy enhanced the effect of knowledge on behaviour change, while perceived susceptibility to dementia mitigated this relationship. Conclusions: The ISLAND framework and interventions, a personalised DRP report and the four-week PDMOOC, work independently and synergistically to increase dementia risk knowledge and stimulate health behaviour change for dementia risk reduction. ISLAND offers a feasible and scalable public health approach for redressing the rising prevalence of dementia. [ABSTRACT FROM AUTHOR]

Objectives: Unequal access to cognitive assessments is a major barrier to timely diagnosis, especially for those living in rural or remote areas. 'One‐stop' cognitive clinic models are a proposed solution, but few such clinics exist. We evaluate the implementation of a new one‐stop State‐wide clinic model in Tasmania, Australia, where 27% of people live in rural/remote areas. Methods: A novel single‐visit protocol has been developed, comprising interdisciplinary medical and cognitive assessments, research participation, consensus diagnosis and management plan. A cross‐sectional evaluation was undertaken using the RE‐AIM (reach, effectiveness, adoption, implementation, maintenance) framework and results benchmarked against the national Australian Dementia Network Registry. Results: Over the first 52 consecutive weekly clinics: Reach: 130 adults were assessed (mean age [SD] 70.12 years [10.31]; 59.2% female) with 40 (36.8%) from rural/remote areas. Effectiveness: 98.5% (128/130) received a same‐day diagnosis: 30.1% (n = 40) Subjective Cognitive Decline, 35.4% (46) Mild Cognitive Impairment, 33.1% (43) dementia and one case inconclusive. Adoption: 22.9% (156) of General Practitioners referred patients. Implementation: Nearly all 'ideal' diagnostic clinical practices were met and >90% of surveyed patients reported 'good/very good' clinic experience. The wait from referral to diagnosis was 2 months shorter than other national Registry clinics (78 vs. 133 days). Conclusions: This 'one‐stop' model provides an interdisciplinary consensus cognitive diagnosis quickly and is well accepted; this may reduce health inequities especially for people living in rural/remote areas. This cognitive clinic model may be of relevance to other centres worldwide and also provides a rich data source for research studies. Key points: Access to cognitive assessments is unequal, especially for people living in rural areas.A 'one‐stop' cognitive clinic resulted in 98.5% same‐day diagnosis, 2 months earlier than the national averageOne‐third of people assessed were from rural/remote areas.This model may inform service design for centres worldwide and provides rich data for research. [ABSTRACT FROM AUTHOR]

While the prevalence of non-communicable disease risk factors is understood to be higher among migrants than for people born in host nations, little is known about the dementia risk profile of migrants, refugees and asylum seekers. This systematic review examines published literature to understand what is currently reported about 12 identified modifiable risk factors for dementia among migrants, refugees, and asylum seekers residing in Australia. Three literature databases (PubMed/CINAHL/MEDLINE) were systematically searched to find articles reporting excessive alcohol consumption, traumatic brain injury, air pollution, lack of education, hypertension, hearing impairment, smoking, obesity, depression, physical inactivity, diabetes, and limited social contact in Australia's migrant, refugee and asylum seeker population samples. Papers were systematically reviewed following PRISMA guidelines. A total of 763 studies were found, of which 676 articles were excluded, and 79 articles remained. Despite wide variability in study design, size and purpose, the prevalence and correlates of modifiable risk factors of dementia appears markedly different among the studied samples. Compared with Australian-born participants, migrant samples had a higher prevalence of depression, social isolation, physical inactivity and diabetes mellitus. Insufficient information or conflicting evidence prevented inference about prevalence and correlates for the remaining dementia risk factors. A better understanding of the prevalence and correlates of modifiable dementia risk factors is needed in Australia's migrant, refugee and asylum seeker populations. This information, together with a deeper understanding of the contextual and cultural contributing factors affecting people who arrive in Australia through differing pathways is needed before preventive interventions can be realistically targeted and sensitively implemented. [ABSTRACT FROM AUTHOR]

Cognitive reserve (CR) is a theoretical construct describing the underlying cognitive capacity of an individual that confers differential levels of resistance to, and recovery from, brain injuries of various types. To date, estimates of an individual's level of CR have been based on single proxy measures that are retrospective and static in nature. To develop a measure of dynamic change in CR across a lifetime, we previously identified a latent factor, derived from an exploratory factor analysis of a large sample of healthy older adults, as current CR (cCR). In the present study, we examined the longitudinal results of a sample of 272 older adults enrolled in the Tasmanian Healthy Brain Project. Using results from 12-month and 24-month reassessments, we examined the longitudinal validity of the cCR factor using confirmatory factor analyses. The results of these analyses indicate that the cCR factor structure is longitudinally stable. These results, in conjunction with recent results from our group demonstrating dynamic increases in cCR over time in older adults undertaking further education, lend weight to this cCR measure being a valid estimate of dynamic change in CR over time. [ABSTRACT FROM AUTHOR]

Objective: To reveal views about dementia diagnosis derived from a larger study of information needs of carers of people with dementia in Tasmania, Australia. Methods: Over 100 participants, including family carers, health professionals and dementia service personnel, met as discrete focus groups. Data pertinent to dementia diagnosis were segregated and subjected to across-group comparative analysis. Results: The term dementia held connotations of stigma and futility, despite stated benefits of having a diagnosis. General practitioners were regarded as pivotal but having inadequate diagnostic and treatment options. While most health professionals advocated a longitudinal diagnostic process, this created considerable stress for family carers who sought a speedy process. Without a diagnosis, some dementia-specific services were undeliverable. Conclusion: Dementia diagnosis is steeped in deep-rooted difficulties and stressful implications, compounded by carers’ differing needs and interests. Better understanding between care providers of their conflicting and consistent views could contribute to better dementia care. [ABSTRACT FROM AUTHOR]

Background and Objectives: Females have a higher age-adjusted incidence of Alzheimer disease than males but the reasons for this remain unclear. One proposed contributing factor is that, historically, females had less access to education and, therefore, may accumulate less cognitive reserve. However, educational attainment is confounded by IQ, which in itself is a component of cognitive reserve and does not differ between sexes. Steeper age-related cognitive declines are associated with increased risk of dementia. We, therefore, evaluated the moderating effects of 2 proxies for cognitive reserve, education and IQ, on the steepness of age-related declining cognitive trajectories in unimpaired older males and females., Methods: The Tasmanian Healthy Brain Project, a long-term cohort study, recruited healthy Australians aged 50-80 years without cognitive impairment. Baseline cognitive reserve was measured using educational history and IQ, measured by the Wechsler Test of Adult Reading, Full Scale Predicted IQ (WTAR-FSIQ). Cognitive trajectories for language, executive function, and episodic and working memory over 5 years were extracted from neuropsychological assessments. The adjusted effects of education, estimated IQ, and APOE allelic variant on cognitive trajectories were compared between males and females., Results: Five hundred sixty-two individuals (mean [SD] age 60 [6.7] years; 68% male; 33% APOE ε4+) were followed up over 5 years with 1,924 assessments and 24,946 cognitive test scores (annualized attrition rate 6.6% per year). Estimated IQ correlated with years of education ( p < 0.001). Estimated IQ interacted with sex to moderate age-related cognitive trajectories ( p = 0.03; adjusted for education); lower IQ males experienced steeper declining trajectories than higher IQ males, but lower IQ females had similar steepness of declining trajectories to higher IQ females. Education was not associated with rate of cognitive decline ( p = 0.67; adjusted for WTAR-FSIQ). There were no significant differences in age-related cognitive trajectories between APOE genotypes in either sex., Discussion: IQ, a measure of cognitive reserve, predicted the steepness of declining cognitive trajectories in males only. Education did not explain as much variation in cognitive trajectories as IQ. Our findings do not support the hypothesis that historical sex disparities in access to education contribute to the higher female incidence of Alzheimer disease., (© 2022 American Academy of Neurology.)

Traumatic brain injury (TBI) can cause persistent cognitive changes and ongoing neurodegeneration in the brain. Accumulating epidemiological and pathological evidence implicates TBI in the development of Alzheimer's disease, the most common cause of dementia. Further, the TBI-induced form of dementia, called chronic traumatic encephalopathy, shares many pathological hallmarks present in multiple different diseases which cause dementia. The inflammatory and neuritic responses to TBI and dementia overlap, indicating that they may share common pathological mechanisms and that TBI may ultimately cause a pathological cascade culminating in the development of dementia. This review explores Australian pre-clinical research investigating the pathological links between TBI and dementia.

Background: Differences in the level of cognitive compromise between individuals following brain injury are thought to arise from underlying differences in cognitive reserve. The level of cognitive reserve attained by an individual is influenced by both genetic and life experience factors such as educational attainment and occupational history. The Tasmanian Healthy Brain Project (THBP) is a world-first prospective study examining the capacity of university-level education to enhance cognitive reserve in older adults and subsequently reduce age-related cognitive decline and risk for neurodegenerative disease., Methods: Up to 1,000 adults aged 50-79 years at the time of entry into the study will be recruited to participate in the THBP. All participants will be healthy and free of significant medical, psychological, or psychiatric illness. Of the participant sample, 90% will undertake a minimum of 12 months part-time university-level study as an intervention. The remaining 10% will act as a control reference group. Participants will complete an annual comprehensive assessment of neuropsychological function, medical health, socialization, and personal well-being. Premorbid estimates of past cognitive, education, occupational, and physical function will be used to account for the mediating influence of prior life experience on outcomes. Potential contributing genetic factors will also be explored., Results: Participant results will be assessed annually. Participants displaying evidence of dementia on the comprehensive neuropsychological assessment will be referred to an independent psycho-geriatrician for screening and diagnosis., Conclusions: The THBP commenced in 2011 and is expected to run for 10-20 years duration. To date, a total of 383 participants have been recruited into the THBP.

Purpose: Inheritance of a particular apolipoprotein E gene polymorphism, the epsilon4 allele, has been associated with elevated risk for Alzheimer's disease and a poor outcome following head injury. The neuronal injury associated with Alzheimer's disease and brain injury may have a number of similarities with the nerve cell changes associated with glaucoma. Thus, we have investigated the association of inheritance of apolipoprotein E allelic isoforms (epsilon2, [epsilon]3, and epsilon4) with relative risk for different forms of glaucoma., Methods: Apolipoprotein E genotype was examined in a Tasmanian population sample comprised of glaucoma sufferers with elevated or normal intraocular pressure and compared to a control sample of elderly Tasmanians without glaucoma., Results: Approximately twice as many normal tension (38.0%) and high tension (34.2%) glaucoma cases possessed an epsilon4 allele compared to control cases (18.9%). The odds of epsilon4 carriers having normal tension glaucoma were significantly greater than for epsilon3 homozygotes (odds ratio 2.45, 95% confidence interval [1.02-5.91]) even after adjusting for age and gender (odd ratio 2.87 [1.02-8.05]). The increased odds of high tension glaucoma among [epsilon]4 allele carriers were not significant (adjusted odds ratio 1.53 [0.64-3.68])., Conclusions: The data indicate that, in the Tasmanian population, inheritance of the [epsilon]4 allele is associated with elevated risk for glaucomatous changes that are not related to increased intraocular pressure.