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The research community in Australia is building a national infrastructure to facilitate access to and sharing of data from health studies. A federation of nine nodes representing 72 health research organisations provides coordination across their partners to establish systems, processes and relationships promoting FAIR approaches to clinical trial data. This paper describes this initiative. [ABSTRACT FROM AUTHOR]

Objective: Mild cognitive impairment (MCI) is considered an intermediate stage between normal aging and dementia. It is diagnosed in the presence of subjective cognitive decline and objective cognitive impairment without significant functional impairment, although there are no standard operationalizations for each of these criteria. The objective of this study is to determine which operationalization of the MCI criteria is most accurate at predicting dementia.Design: Six-year longitudinal study, part of the Sydney Memory and Ageing Study.Setting: Community-based.Participants: 873 community-dwelling dementia-free adults between 70 and 90 years of age. Persons from a non-English speaking background were excluded.Measurements: Seven different operationalizations for subjective cognitive decline and eight measures of objective cognitive impairment (resulting in 56 different MCI operational algorithms) were applied. The accuracy of each algorithm to predict progression to dementia over 6 years was examined for 618 individuals.Results: Baseline MCI prevalence varied between 0.4% and 30.2% and dementia conversion between 15.9% and 61.9% across different algorithms. The predictive accuracy for progression to dementia was poor. The highest accuracy was achieved based on objective cognitive impairment alone. Inclusion of subjective cognitive decline or mild functional impairment did not improve dementia prediction accuracy.Conclusions: Not MCI, but objective cognitive impairment alone, is the best predictor for progression to dementia in a community sample. Nevertheless, clinical assessment procedures need to be refined to improve the identification of pre-dementia individuals. [ABSTRACT FROM AUTHOR]

The Older Australian Twins Study (OATS) is a major longitudinal study of twins, aged ≥ 65 years, to investigate genetic and environmental factors and their interactions in healthy brain ageing and neurocognitive disorders. The study collects psychiatric, neuropsychological, cardiovascular, metabolic, biochemical, neuroimaging, genomic and proteomic data, with two-yearly assessments, and is currently in its third wave. The initial cohort comprises 623 individuals (161 monozygotic and 124 dizygotic twin pairs; 1 MZ triplets; 27 single twins and 23 non-twin siblings), of whom 426 have had wave 2 assessment. A number of salient findings have emerged thus far which assist in the understanding of genetic contributions to cognitive functions such as processing speed, executive ability and episodic memory, and which support the brain reserve hypothesis. The heritability of brain structures, both cortical and subcortical, brain spectroscopic metabolites and markers of small vessel disease, such as lacunar infarction and white matter hyperintensities, have been examined and can inform future genetic investigations. Work on amyloid imaging and functional magnetic resonance imaging is proceeding and epigenetic studies are progressing. This internationally important study has the potential to inform research into cognitive ageing in the future, and offers an excellent resource for collaborative work. [ABSTRACT FROM AUTHOR]

Background: The study of exceptionally long-living individuals can inform us about the determinants of successful aging. There are few population-based studies of centenarians and near-centenarians internationally, but none in Australia.Methods: Individuals 95 years and older were recruited from seven electoral districts in Sydney using the electoral roll, Medicare lists, and multiple other strategies to obtain a representative sample. Physical and mental health and cognitive status were assessed using standard instruments in multiple sessions, with assessments individually adapted. An informant was interviewed, and participants were invited to donate a blood sample, undergo an MRI scan, and enrol into the brain donation program.Results: Preliminary data on the first 200 participants are reported. Mean age was 97.4 years (range 95–106), with 29.5% being men, and 58.5% living in a private dwelling. Rates of heart disease and diabetes were lower than in octogenarians, but hearing and visual deficits were common. The mean mini-mental state examination (MMSE) score was 21.1, with men performing better. Rates of psychological distress were low and satisfaction with life high (mean 5.91 out of a maximum of 7); 54% scored <24 on MMSE; 39.5% were impaired on both MMSE and a functional measure; and 20% had previous diagnosis of dementia.Conclusions: This is a preliminary report describing the methodology of the study. It provides further evidence that dementia is not inevitable at this age and independent living is common. The study provides an excellent resource to determine the genetic and environmental contributions to long and successful cognitive aging. [ABSTRACT FROM AUTHOR]

Introduction: Mild cognitive impairment (MCI) is associated with an increased risk of developing dementia. However, many individuals diagnosed with MCI are found to have reverted to normal cognition on follow-up. This study investigated factors predicting or associated with reversion from MCI to normal cognition. Methods: Our analyses considered 223 participants (48.9% male) aged 71–89 years, drawn from the prospective, population-based Sydney Memory and Ageing Study. All were diagnosed with MCI at baseline and subsequently classified with either normal cognition or repeat diagnosis of MCI after two years (a further 11 participants who progressed from MCI to dementia were excluded). Associations with reversion were investigated for (1) baseline factors that included diagnostic features, personality, neuroimaging, sociodemographics, lifestyle, and physical and mental health; (2) longitudinal change in potentially modifiable factors. Results: There were 66 reverters to normal cognition and 157 non-reverters (stable MCI). Regression analyses identified diagnostic features as most predictive of prognosis, with reversion less likely in participants with multiple-domain MCI (p = 0.011), a moderately or severely impaired cognitive domain (p = 0.002 and p = 0.006), or an informant-based memory complaint (p = 0.031). Reversion was also less likely for participants with arthritis (p = 0.037), but more likely for participants with higher complex mental activity (p = 0.003), greater openness to experience (p = 0.041), better vision (p = 0.014), better smelling ability (p = 0.040), or larger combined volume of the left hippocampus and left amygdala (p<0.040). Reversion was also associated with a larger drop in diastolic blood pressure between baseline and follow-up (p = 0.026). Discussion: Numerous factors are associated with reversion from MCI to normal cognition. Assessing these factors could facilitate more accurate prognosis of individuals with MCI. Participation in cognitively enriching activities and efforts to lower blood pressure might promote reversion. [ABSTRACT FROM AUTHOR]

Objective: While activities of daily living are by definition preserved in mild cognitive impairment (MCI), there is evidence of poorer instrumental activities of daily living (IADL) functioning in MCI compared to normal ageing. The aims of the present study were to examine differences in IADL between individuals with MCI and cognitively normal elderly, and to examine the relationships of IADL with cognitive functions. Methods: The sample of 762 community-living participants aged 70–90 were assessed with a comprehensive neuropsychological test battery and with the informant-completed Bayer-Activities of Daily Living Scale (B-ADL). Results: Compared to cognitively normal individuals, the MCI group was rated as having more difficulties on the B-ADL and performed worse on cognitive tests. Factor analysis of the B-ADL items yielded two factors, which were labelled ‘high cognitive demand’ (HCD) and ‘low cognitive demand’ (LCD). Individuals with MCI scored worse than cognitively normal participants on the HCD factor but similarly on the LCD factor. Men were rated as having more difficulties on the HCD, but not the LCD, factor compared to women. The HCD factor score correlated significantly with all five cognitive domains measured, but the LCD factor correlated significantly only with attention/processing speed and to a lesser extent with executive function. Conclusions: Having more difficulties in IADL, especially those with higher demand on cognitive capacities, was found to be associated with MCI and overall cognitive functioning. This has implications for the definition of MCI, as lack of functional impairment is generally used as a criterion for diagnosis. [ABSTRACT FROM AUTHOR]

The basal forebrain area (BFA) is closely connected to the hippocampus by virtue of cholinergic neuronal projections. Structural neuroimaging studies have shown reduced volumes of both structures in Alzheimer's disease and its prodromal stage mild cognitive impairment (MCI), but generally not in the same investigation. By combining voxel based morphometry and region of interest methods, we measured the grey matter (GM) volumes of the two brain regions with the goal of elucidating their contributions to MCI and its two subtypes (amnestic MCI and non-amnestic MCI) in an elderly epidemiological sample. The results replicated previous findings that the atrophies of both brain regions were associated with an increased likelihood of MCI and its two subtypes. However, in a regression model for the prediction of MCI with GM volumes for both regions used as predictors, only hippocampal atrophy remained significant. Two possible interpretations for this pattern of results were discussed. One is that the observed correlation between BFA atrophy and MCI is spurious and due to the hippocampal atrophy correlated with both. Alternatively, our observation is consistent with the possibility that BFA atrophy has a causal effect on MCI, which is mediated via its influence on hippocampal atrophy. Furthermore, we found that the left hippocampal atrophy had a stronger effect than the right hippocampus and bilateral BFA in the prediction of amnestic MCI occurrence when the four unilateral areas were entered into one regression model. In addition, a slight but statistically significant difference was found in the left hippocampal volume between APOE 4 allele carriers and non-carriers, consistent with prior studies. [ABSTRACT FROM AUTHOR]

Background: The Sydney Memory and Ageing Study (Sydney MAS) was initiated in 2005 to examine the clinical characteristics and prevalence of mild cognitive impairment (MCI) and related syndromes, and to determine the rate of change in cognitive function over time. Methods: Non-demented community-dwelling individuals (N=1037) aged 70-90 were recruited from two areas of Sydney, following a random approach to 8914 individuals on the electoral roll. They underwent detailed neuropsychiatric and medical assessments and donated a blood sample for clinical chemistry, proteomics and genomics. A knowledgeable informant was also interviewed. Structural MRI scans were performed on 554 individuals, and subgroups participated in studies of falls and balance, metabolic and inflammatory markers, functional MRI and prospective memory. The cohort is to be followed up with brief telephone reviews annually, and detailed assessments biannually. Results: This is a generally well-functioning cohort mostly living in private homes and rating their health as being better than average, although vascular risk factors are common. Most (95.5%) participants or their informants identified a cognitive difficulty, and 43.5% had impairment on at least one neuropsychological test. MCI criteria were met by 34.8%; with19.3% qualifying for amnestic MCI, whereas 15.5% had non-amnestic MCI; 1.6% had impairment on neuropsychological test performance but no subjective complaints; and 5.8% could not be classified. The rate of MCI was 30.9% in the youngest (70-75) and 39.1% in the oldest (85-90) age bands. Rates of depression and anxiety were 7.1% and 6.9% respectively. Conclusions: Cognitive complaints are common in the elderly, and nearly one in three meet criteria for MCI. Longitudinal follow-up of this cohort will delineate the progression of complaints and objective cognitive impairment, and the determinants of such change. [ABSTRACT FROM AUTHOR]