In addition to being highly prevalent, hearing and vision impairment affect older adults for substantial periods of their remaining life. Given their broad ranging impacts on health and well-being, sensory impairments are ideal targets for strategies to compress morbidity in late life.
Our largely theory-based findings suggest a strong case for greater investment in risk factor reduction programmes that target modifiable lifestyle factors, particularly increased engagement in physical activity. However, further data on risk factor treatment and dementia risk reduction from population-based studies are needed to investigate whether our estimates of potential dementia prevention are indeed realistic.
Driving is normative for many older Australians in their 70s. Similar factors are associated with actual cessation and expectation of driving suggesting that older adults do have a sense of their expected driving life.
We aimed to evaluate risk of unsafe on-road driving performance among older adults with MCI. Adults with MCI exhibit a similar range of driving ability to CN adults, although on average they scored lower on off-road and on-road assessments. Driving specific tests were more strongly associated with safety ratings than traditional neuropsychological tests.
In the general population, the ANU-ADRI, comprising lifestyle, medical and demographic factors, is associated with the risk of progression from CN to MCI, whereas a GRS comprising the main AD risk genes was not associated with this risk. The ANU-ADRI may be used for population-level risk assessment and screening.
Mid-life cannabis users had poorer verbal recall than non-users, but this was not related to their current level of cannabis use, and cannabis use was not associated with accelerated cognitive decline.
To design a low-cost simulator-based driving assessment for older adults and to compare its validity with that of an on-road driving assessment and other measures of older driver risk. A low-cost simulator-based assessment is valid as a screening instrument for identifying at-risk older drivers but not as an alternative to on-road evaluation when accurate data on competence or pattern of impairment is required for licensing decisions and training programs.
Objective. To examine the effect of diabetes treatment on change of measures of specific cognitive domains over 4 years. Research Design and Methods. The sample was drawn from a population-based cohort study in Australia (the PATH Through Life Study) and comprised 1814 individuals aged 65-69 years at first measurement, of whom 211 were diagnosed with diabetes. Cognitive function was measured using 10 neuropsychological tests. The effect of type of diabetes treatment (diet, oral hypoglycemic agents, and insulin) on measures of specific cognitive domains was assessed using Generalized Linear Models adjusted for age, sex, education, smoking, physical activity level, BMI, and hypertension. Results. Comparison of cognitive function between diabetes treatment groups showed no significant effect of type of pharmacological treatment on cognitive function compared to diet only group or no diabetes group. Of those on oral hypoglycaemic treatment only, participants who used metformin alone had better cognitive function at baseline for the domains of verbal learning, working memory, and executive function compared to participants on other forms of diabetic treatment. Conclusion. This study did not observe significant effect from type of pharmacological treatment for diabetes on cognitive function except that participants who only used metformin showed significant protective effect from metformin on domain of verbal learning, working memory, and executive function.
Grading instruments are an important part of evidence-based medicine and are used to inform health policy and the development of clinical practice guidelines. They are extensively used in the development of clinical guidelines and the assessment of research publications, having particular impact on health care and policy sectors. The positive effects of using grading instruments are, however, potentially undermined by their misuse and a number of shortcomings. This review found eight key concerns about grading instruments: (1) lack of information on validity and reliability, (2) poor concurrent validity, (3) may not account for external validity, (4) may not be inherently logical, (5) susceptibility to subjectivity, (6) complex systems with inadequate instructions, (7) may be biased toward randomized controlled trial (RCT) studies, and (8) may not adequately address the variety of non-RCTs. This narrative review concludes that there is a need to take into account these criticisms and domain-specific limitations, to enable the use and development of the most appropriate grading instruments. Grading systems need to be matched to both the research question being asked and the type of evidence being used.
To determine whether dance benefits executive function more than walking, an activity that is simple and functional. The superior potential of dance over walking on executive functions of cognitively healthy and active older adults was not supported. Dance improved one of the cognitive domains (spatial memory) important for learning dance. Controlled trials targeting inactive older adults and of a higher dose may produce stronger effects, particularly for novice dancers.
With the number of older drivers projected to increase by up to 70% over the next 20 years, preventing injury resulting from crashes involving older drivers is a significant concern for both policy-makers and clinicians. While the total number of fatal crashes per annum has steadily decreased since 2005 in Australia, the rate of fatalities has demonstrated an upward trend since 2010 in drivers aged 65 years and above (8.5 per 100,000), such that it is now on par with the fatality rate in drivers aged 17-25 years (8.0 per 100,000) (Austroads, 2015). Similar statistics are reported for the United States (NHTSA, 2012), implying there is a need for better identification of those older drivers who are unsafe and implementation of strategies that can enhance mobility while maximizing road safety.
Dementia risk reduction is a global health and fiscal priority given the current lack of effective treatments and the projected increased number of dementia cases due to population ageing. There are often gaps among academic research, clinical practice, and public policy. We present information on the evidence for dementia risk reduction and evaluate the progress required to formulate this evidence into clinical practice guidelines. This narrative review provides capsule summaries of current evidence for 25 risk and protective factors associated with AD and dementia according to domains including biomarkers, demographic, lifestyle, medical, and environment. We identify the factors for which evidence is strong and thereby especially useful for risk assessment with the goal of personalising recommendations for risk reduction. We also note gaps in knowledge, and discuss how the field may progress towards clinical practice guidelines for dementia risk reduction.
Those with type 2 diabetes, younger males with high non-diabetic HbA1c, and adults with high stable blood glucose are at increased risk of poorer cognition. The findings reinforce the need for management of diabetes risk factors in midlife.
The development and integration of risk assessment and clinical risk management for Alzheimer's disease (AD) and dementia is a rapidly emerging field of research and practice. At present, risk management is the only available approach with potential for a large impact on the projected rates of dementia, given population aging. This review describes six available risk assessment tools, including those developed specifically for AD and those for dementia. These tools differ along several important dimensions, including whether they (a) include clinical measures, (b) require a clinician's ratings, (c) are predominantly self-report, (d) are independently validated, and (e) are available online. A narrative review of recently identified risk factors not included in these instruments is included, indicating future directions for risk assessment. Finally, consideration is given to the prioritization of risk advice according to the ease of risk modification and the potential for synergies among risk factors.
There is continuing debate about long-term effects of brain injury. We examined a range of traumatic brain injury (TBI) variables (TBI history, severity, frequency, and age of injury) as predictors of cognitive outcome over 8 years in an adult population, and interactions with apolipoprotein E (APOE) genotype, sex, and age cohorts. Three randomly sampled age cohorts (20-24, 40-44, 60-64 years at baseline; N = 6333) were each evaluated three times over 8 years. TBI variables, based on self-report, were separately modeled as predictors of cognitive performance using linear mixed effects models. TBI predicted longitudinal cognitive decline in all three age groups. APOE ε4 + genotypes in the young and middle-aged groups predicted lower baseline cognitive performance in the context of TBI. Baseline cognitive performance was better for young females than males but this pattern reversed in middle age and old age. The findings suggest TBI history is associated with long-term cognitive impairment and decline across the adult lifespan. A role for APOE genotype was apparent in the younger cohorts but there was no evidence that it is associated with impairment in early old age. The effect of sex and TBI on cognition varied with age cohort, consistent with a proposed neuroprotective role for estrogen.
This study examined the prevalence of co-morbid age-related eye disease and symptoms of depression and anxiety in late life, and the relative roles of visual function and disease in explaining symptoms of depression and anxiety. A community-based sample of 662 individuals aged over 70 years was recruited through the electoral roll. Vision was measured using a battery of tests including high and low contrast visual acuity, contrast sensitivity, motion sensitivity, stereoacuity, Useful Field of View, and visual fields. Depression and anxiety symptoms were measured using the Goldberg scales. The prevalence of self-reported eye disease [cataract, glaucoma, or age-related macular degeneration (AMD)] in the sample was 43.4%, with 7.7% reporting more than one form of ocular pathology. Of those with no eye disease, 3.7% had clinically significant depressive symptoms. This rate was 6.7% among cataract patients, 4.3% among those with glaucoma, and 10.5% for AMD. Generalized linear models adjusting for demographics, general health, treatment, and disability examined self-reported eye disease and visual function as correlates of depression and anxiety. Depressive symptoms were associated with cataract only, AMD, comorbid eye diseases and reduced low contrast visual acuity. Anxiety was significantly associated with self-reported cataract, and reduced low contrast visual acuity, motion sensitivity and contrast sensitivity. We found no evidence for elevated rates of depressive or anxiety symptoms associated with self-reported glaucoma. The results support previous findings of high rates of depression and anxiety in cataract and AMD, and in addition show that mood and anxiety are associated with objective measures of visual function independently of self-reported eye disease. The findings have implications for the assessment and treatment of mental health in the context of late-life visual impairment.
Few studies report incidence of mild cognitive impairment (MCI) and other mild cognitive disorders (MCD) in cohorts in their 60s, at an age when diagnoses are less stable. The authors' goal was to estimate the incidence and prevalence of MCI and MCD, characterize subgroups with stable vs nonstable diagnoses, and evaluate the impact of diagnosis on daily life in a young-old cohort. MCDs in individuals in their 60s occur in at least 10% of the population and are likely to be heterogeneous in terms of their etiology and long-term prognosis, but may cause a significant impact in everyday life.
In this relatively young cohort, retrospective self-report of cognitive decline does not reflect objective deterioration in cognition over the time period in question, but it may identify individuals in the initial stages of dementia and those with elevated psychological and genotypic risk factors for the development of dementia.
This well-defined sample of older australians provides a unique opportunity to interrogate associations between retinal findings, including retinal vascular geometric parameters, and indices of neurocognitive function.
To investigate self-reported driving status within three Australian states; associations between demographic, health, and functional factors and driving status; and the extent to which remaining a driver in spite of cognitive and visual impairments varies as a function of sex. The rate of men with probable dementia or visual impairments who reported driving is of particular concern. Research and policy need to focus on evidence-based assessment of older drivers and development of appropriate interventions and programs to maintain the mobility and independence of older adults.
Computerized training for cognitive enhancement is of great public interest, however, there is inconsistent evidence for the transfer of training gains to every day activity. Several large trials have focused on speed of processing (SOP) training with some promising findings for long-term effects on daily activity, but no immediate transfer to other cognitive tests. Here, we examine the transfer of SOP training gains to cognitive measures that are known predictors of driving safety in older adults. Fifty-three adults aged 65-87 years who were current drivers participated in a two group non-randomized design with repeated measures and a no-contact matched control group. The Intervention group completed an average of 7.9 ( = 3.0) hours of self-administered online SOP training at home. Control group was matched on age, gender and test-re-test interval. Measures included the Useful Field of View (UFOV) test, a Hazard Perception test, choice reaction time (Cars RT), Trail Making Test B, a Maze test, visual motion threshold, as well as road craft and road knowledge tests. Speed of processing training resulted in significant improvement in processing speed on the UFOV test relative to controls, with an average change of -45.8 ms ( = 14.5), and effect size of ω = 0.21. Performance on the Maze test also improved, but significant slowing on the Hazard Perception test was observed after SOP training. Training effects on the UFOV task was associated with similar effects on the Cars RT, but not the Hazard Perception and Maze tests, suggesting transfer to some but not all driving related measures. There were no effects of training on any of the other measures examined. Speed of processing training effects on the UFOV task can be achieved with self-administered, online training at home, with some transfer to other cognitive tests. However, differential effects of training may be observed for tasks requiring goal-directed search strategies rather than diffuse attention.
As death approaches, there are increases in the levels of depressive symptomology even after controlling for socio-demographic and health covariates. In line with increases in suicide rates in late life, male participants were at greater risk of reporting increases in depressive symptomology.
The Mini-Mental State Examination (MMSE) is used to estimate current cognitive status and as a screen for possible dementia. Missing item-level data are commonly reported. Attention to missing data is particularly important. However, there are concerns that common procedures for dealing with missing data, for example, listwise deletion and mean item substitution, are inadequate. Our adaptation of MI to obtain a probable estimate for missing MMSE item level data provides a suitable method when the proportion of missing item-level data is not excessive.
Depressive symptoms and cognitive decline are associated in older age, but research is inconsistent about whether one condition influences the development of the other. We examined the directionality of relations between depressive symptoms and perceptual speed using bivariate dual change score models. Assessments of depressive symptoms and perceptual speed were completed by 1,206 nondemented older adults at baseline, and after 2, 8, 11, and 15 years. After controlling for age, education, baseline general cognitive ability, and self-reported health, allowing depressive symptoms to predict subsequent change in perceptual speed provided the best fit. More depressive symptoms predicted subsequently stronger declines in perceptual speed over time lags of 1 year.
Population level reductions in smoking, sedentary lifestyle and obesity increase longevity and number of years lived without cognitive impairment. Years lived with cognitive impairment may also increase.
Evidence-based policy depends on the availability of high-quality research that is relevant to the population. This study aimed to identify the available data on the health of older Indigenous Australians in population-based longitudinal studies of ageing. Within the existing Australian longitudinal ageing studies, Indigenous Australians are under-represented. This means there is a significant gap in the evidence base relating to the health of older Indigenous Australians. Research approaches specifically designed to address the health and wellbeing of older Indigenous Australians are urgently required.
Tailored driving lessons reduced the critical driving errors made by older adults. Longer term follow-up and larger trials are required.
This study shows that estimates of probable dementia based on MMSE in studies where cognitive decline and dementia are a focus, are a useful adjunct to clinical studies of dementia prevalence. Such information and may be used to inform projections of dementia prevalence and the concomitant burden of disease.
This study investigates the functional equivalence of two measures of irregular word pronunciation–National Adult Reading Test (NART) and Schonell–which are popular instruments used to assess verbal neurocognitive functioning and to estimate premorbid IQ. We report norms for the NART in a pooled sample from 3 Australian population-based studies of adults aged 65-103 years. Norms were stratified by sex and age left school in 5-year age groups. The NART and the Schonell had a strong linear relation, allowing for the imputation of NART scores based on Schonell performance within 1 study. Neither measure was sensitive to the effects of sex after adjusting for the effects of age and education. Early school leavers performed worse on both measures. Data pooling enables greater precision and improved generalizability of NART norms than do methods that use single older adult samples.
Faster rates of decline in hearing are predicted by probable cognitive impairment and hypertension.
To evaluate a harmonized binary measure of self-reported hearing loss against gold standard audiometry in an older adult population.
Vision and HL are highly prevalent among older adults and their co-occurrence may compound their respective impacts on health, functioning, and activity engagement, thereby exerting strong effects on the mental health and wellbeing of those affected. There is therefore a need for rehabilitation programs to be sensitive to the combined effects of sensory loss on individuals.
This study presents the first population-based prevalence estimates for MBI using the recently published ISTAART-AA diagnostic criteria. Findings indicate relatively high prevalence of MBI in pre-dementia clinical states and amongst cognitively healthy older adults. Findings were gender-specific, with MBI affecting more men than women. Knowing the estimates of these symptoms in the population is essential for understanding and differentiating the very early development of clinical disorders.
The extent to which this association is the result of underlying neuropathology, unmet need, or interpersonal factors is unclear. These findings have significant implications for dementia care settings, including hospitals and respite care, as patients with sensory loss are at increased risk of neuropsychiatric symptoms and may require additional psychosocial support. Interventions to manage sensory loss and reduce the impact of sensory limitations on neuropsychiatric symptoms are needed.
To characterize the prevalence of NPS and explore the clinical implications of co-morbid symptom presentation. Our findings confirm previous reports on the prevalence of NPS in community-based samples and are consistent with the profiles of NPS domain characteristics of MCI and dementia. Number of co-morbid NPS and not symptom clusters are associated with increased risk of dementia. Understanding such patterns will help inform our understanding of mild behavioral disorders and assist with clinical assessment.
DSM-5 NCD criteria can be operationalized in a psychometric algorithm in a population setting. Expert diagnosis using DSM-5 NCD criteria captured most cases with DSM-IV dementia and MCI in our sample, but included many additional cases suggesting that DSM-5 criteria are broader in their categorization.
In this cohort of older individuals, higher MAP was associated with larger regional volume and better cognition in men, whereas opposite findings were demonstrated in women. These effects may be due to different lifetime risk exposure or because of physiological differences between men and women. Future studies investigating the relationship between blood pressure and brain structure or cognitive function should evaluate the potential for differential sex effects.
The protective effect of education on cognitive and brain health is well established. While the direct effects of individual cardiovascular disease (CVD) risk factors (i.e., hypertension, smoking, diabetes, and obesity) on cerebral structure have been investigated, little is understood about the possible interaction between the protective effect of education and the deleterious effects of CVD risk factors in predicting brain ageing and cognition. Using data from the PATH Through Life study (N = 266), we investigated the protective effect of education on cerebral structure and function and tested a possible mediating role of CVD risk factors. Higher education was associated with larger regional grey/white matter volumes in the prefrontal cortex in men only. The association between education and cognition was mediated by brain volumes but only for grey matter and only in relation to information processing speed. CVD risk factors did not mediate the association between regional volumes and cognition. This study provides additional evidence in support for a protective effect of education on cerebral structures and cognition. However, it does not provide support for a mediating role of CVD risk factors in these associations.
This study aimed to determine whether blood glucose levels in the normal range (<6.1 mmol/L) were associated with cerebral volumes in structures other than the hippocampus and amygdale, and whether these glucose-related regional volumes were associated with cognitive performance. These findings stress the need to re-evaluate what is considered as healthy blood glucose levels, and consider the role of higher normal blood glucose as a risk factor for cerebral health, cognitive function and dementia. A better lifetime management of blood glucose levels may contribute to improved cerebral and cognitive health in later life and possibly protect against dementia.