Mild Traumatic Brain Injury and Functional Outcome in Older Adults: Pain Interference But Not Cognition Mediates the Relationship Between Traumatic Injury and Functional Difficulties.

OBJECTIVE: To examine functional status of older people 3 months after mild traumatic brain injury (mTBI) and identify whether pain interference or cognition mediates any relationship found between injury status and functional outcomes. SETTING: Patients admitted to a Melbourne-based emergency department. PARTICIPANTS: Older adults 65 years and older: 40 with mTBI, 66 with orthopedic injury without mTBI (TC), and 47 healthy controls (CC) without injury. DESIGN: Observational cohort study. MAIN MEASURES: Functional outcome was measured using the World Health Organization Disability Assessment Schedule (WHODAS 2.0) and single- and dual-task conditions of the Timed-Up-and-Go task. Pain interference and cognitive performance at 3 months post-injury were examined as mediators of the relationship between injury status (injured vs noninjured) and functional outcome. RESULTS: Patients with mTBI and/or orthopedic injury reported greater difficulties in overall functioning, including community participation, compared with noninjured older people (CC group). Both trauma groups walked slower than the CC group on the mobility task, but all groups were similar on the dual-task condition. Pain interference mediated the relationship between injury status and overall functioning [ b = 0.284; 95% CI = 0.057, 0.536), community participation ( b = 0.259; 95% CI = 0.051, 0.485), and mobility ( b = 0.116; 95% CI = 0.019, 0.247). However, cognition did not mediate the relationship between injury status and functional outcomes. CONCLUSIONS: Three months after mild traumatic injury (with and without mTBI), patients 65 years and older had greater functional difficulties compared with noninjured peers. Pain interference, but not cognition, partially explained the impact of traumatic injury on functional outcomes. This highlights the importance of reducing pain interference for older patients after injury (including mTBI) to support better functional recovery.

Quality of life and psychological health after mild traumatic brain injury in older people: Three- and six-month follow up.

OBJECTIVES: Examine quality of life (QoL) and psychological health after mild traumatic brain injury (mTBI) in older people (65+ years) at 3- and 6-month follow-up and explore which injury factors predicted QoL. METHODS: mTBI patients were compared to trauma comparison (TC) and community comparison (CC) groups. QoL and psychological health were measured at both timepoints. After accounting for 3-month psychological health, injury severity, neuroimaging, and 3-month neuropsychological performance were assessed as predictors of 6-month QoL. RESULTS: Overall 3-month QoL was lower for mTBI (Cohen's d = 0.938) and TC (Cohen's d = 0.485) groups compared to CCs, but by 6 months only mTBI patients continued to report poorer overall QoL (Cohen's d = 0.577) and physical QoL (Cohen's d = 0.656). Despite group differences, QoL for most (~92%) was within normative limits. 3-month psychological health predicted QoL 6-months postinjury (ß = -.377, 95% CI -.614, -.140) but other proposed risk factors (GCS <15, neuroimaging, 3-month neuropsychological performance) did not uniquely predict QoL. CONCLUSIONS: Older adults following mTBI reported lower QoL up to 6-months postinjury compared to non-injured peers, indicating that mTBI patients were particularly susceptible to ongoing differences in QoL 6-months postinjury.

Observed Strategies on Naturalistic Associative Memory Tasks in Healthy Older Adults and Amnestic Mild Cognitive Impairment.

BACKGROUND: Understanding the strategies people with amnestic mild cognitive impairment (aMCI) spontaneously use can inform targeted memory training. METHOD: Strategy use was observed for 99 people with aMCI and 100 healthy older adults (HOA) on two memory tasks. RESULTS: No differences were found between aMCI and HOA in the amount or types of strategies used, but strategy use varied with task. Association was more effective for one task, whereas on the other task, use of written notes or multiple strategies were detrimental to performance and related to poorer performance than active (spaced) retrieval, for aMCI. CONCLUSION: Our findings suggest the importance of identifying ineffective habits, in addition to instruction in more beneficial approaches.

Subjective Cognitive Decline: Level of Risk for Future Dementia and Mild Cognitive Impairment, a Meta-Analysis of Longitudinal Studies.

Subjective Cognitive Decline (SCD) in older adults has been identified as a risk factor for dementia, although the literature is inconsistent, and it is unclear which factors moderate progression from SCD to dementia. Through separate meta-analyses, we aimed to determine if SCD increased the risk of developing dementia or mild cognitive impairment (MCI). Furthermore, we examined several possible moderators. Longitudinal studies of participants with SCD at baseline, with data regarding incident dementia or MCI, were extracted from MEDLINE and PsycINFO. Articles were excluded if SCD occurred solely in the context of dementia, MCI, or as part of a specific disease. Pooled estimates were calculated using a random-effects model, with moderator analyses examining whether risk varied according to SCD definition, demographics, genetics, recruitment source, and follow-up duration. Risk of study bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 tool. 46 studies with more than 74,000 unique participants were included. SCD was associated with increased risk of developing dementia (HR = 1.90, 95% CI 1.52-2.36; OR = 2.48, 95% CI 1.97-3.14) and MCI (HR = 1.73, 95% CI 1.18-2.52; OR = 1.83, 95% CI 1.56-2.16). None of the potential moderating factors examined influenced the HR or OR of developing dementia. In contrast, including worry in the definition of SCD, younger age, and recruitment source impacted the OR of developing MCI, with clinic samples demonstrating highest risk. SCD thus represents an at-risk phase, ideal for early intervention, with further research required to identify effective interventions for risk reduction, and cognitive-behavioural interventions for cognitive management. PROSPERO, protocol number: CRD42016037993.

Systematic Review and Meta-analysis of Outcome after Mild Traumatic Brain Injury in Older People.

OBJECTIVE: Older age is often identified as a risk factor for poor outcome from traumatic brain injury (TBI). However, this relates predominantly to mortality following moderate-severe TBI. It remains unclear whether increasing age exerts risk on the expected recovery from mild TBI (mTBI). In this systematic review of mTBI in older age (60+ years), a focus was to identify outcome through several domains - cognition, psychological health, and life participation. METHODS: Fourteen studies were identified for review, using PRISMA guidelines. Narrative synthesis is provided for all outcomes, from acute to long-term time points, and a meta-analysis was conducted for data investigating life participation. RESULTS: By 3-month follow-up, preliminary findings indicate that older adults continue to experience selective cognitive difficulties, but given the data it is possible these difficulties are due to generalised trauma or preexisting cognitive impairment. In contrast, there is stronger evidence across time points that older adults do not experience elevated levels of psychological distress following injury and endorse fewer psychological symptoms than younger adults. Meta-analysis, based on the Glasgow Outcome Scale at 6 months+ post-injury, indicates that a large proportion (67%; 95% CI 0.569, 0.761) of older adults can achieve good functional recovery, similar to younger adults. Nevertheless, individual studies using alternative life participation measures suggest more mixed rates of recovery. CONCLUSIONS: Although our initial review suggests some optimism in recovery from mTBI in older age, there is an urgent need for more investigations in this under-researched but growing demographic. This is critical for ensuring adequate health service provision, if needed.

Long-term effects of a memory group intervention reported by older adults.

The aim of this study was to examine older adults' experiences of change following a group memory intervention, the La Trobe and Caulfield Hospital (LaTCH) Memory Group programme. Semi-structured qualitative interviews were conducted with 30 individuals. Participants were healthy older adults and older adults with amnestic mild cognitive impairment (MCI) who had participated in the memory group five years previously. Transcripts were analysed for emergent themes in a workshop, using the Most Significant Change technique. The focus group derived four major themes relating to participants' experiences of change. Particularly noteworthy were themes describing a process of acceptance and normalising of memory difficulties in older age, as well as enhancement of coping and self-efficacy. The results highlight the importance of group support for older adults with and without objective memory impairment. Memory groups may use the group format to full advantage by (a) enhancing participants' experiences of universality to alleviate distress and promote coping, and (b) developing group norms to promote positive ageing, encompassing enhanced acceptance and self-efficacy.

Making sense of self in Alzheimer's disease: reflective function and memory.

OBJECTIVE: The current investigation examined the relationship between cognitive impairment and sense of self in Alzheimer's disease (AD). METHOD: Forty-nine participants with dementia associated with AD were recruited through memory clinics in Victoria, Australia. The 26 participants of the healthy control sample were recruited from a retirement village. Self was measured via the Reflective Self-Function Scale - a theory of mind indicator that provides personal and social self-reflection scores. Cognitive assessment included measures of new learning, executive function, and speed of information processing. RESULTS: A reduction in sense of self in mild AD was demonstrated in both personal and social domains, as compared to healthy adults of a similar age. With a focus on specific cognitive impairment relationships, new learning was found to predict personal self-reflection, whereas speed of information processing predicted social self-reflection capacity. CONCLUSION: Findings suggest that deficits in new learning ability contribute to a reduced ability of people with early AD to understand their mental world and interpret thoughts, feelings, and beliefs about themselves. This impaired capacity to self-reflect will be intrusive in daily activities that require monitoring of current self-performance. Furthermore, with reduced speed of information processing found to impact on ability to reflect on social relations, individuals with AD are placed at risk of reduced ability to understand their social world, including communicating and interacting with others. Notwithstanding the overall group findings, individual variability was evident which reinforces the need for person-centred care in dementia.

Naturalistic prospective memory in older adults: Predictors of performance on a habitual task.

Age-related difficulties in episodic prospective memory (PM) are common. However, little is known about habitual PM, which involves remembering to carry out intended actions that are regular and repeated. This is important for many health-related tasks and for maintaining independence in daily living activities. This study investigates, in older people, the predictors of habitual PM performance in a naturalistic setting. A group of 191 community-based, older adults (aged 65-89 years) wore an actigraph over two weeks. The habitual PM task involved pressing a button twice daily (Bed-time, Rise-time) on the actigraph. Accuracy of response was calculated for Bed-time and Rise-time, determined by light, movement, and diary data. The contribution of retrospective memory and executive function to PM performance was assessed. PM was more accurate at Bed-time compared to Rise-time (p < .01), and better in the first compared to the second week (p < .01). Retrospective memory contributed small but significant unique variance (ß = .24) to PM accuracy. For older adults living in the community, both contextual factors (e.g., time of day) and retrospective memory are important for individuals' ability to remember to perform daily tasks. This is relevant when planning interventions for maintaining independent living in ageing.

Objective but not subjective sleep predicts memory in community-dwelling older adults.

Research on the relationship between habitual sleep patterns and memory performance in older adults is limited. No previous study has used objective and subjective memory measures in a large, older-aged sample to examine the association between sleep and various domains of memory. The aim of this study was to examine the association between objective and subjective measures of sleep with memory performance in older adults, controlling for the effects of potential confounds. One-hundred and seventy-three community-dwelling older adults aged 65-89 years in Victoria, Australia completed the study. Objective sleep quality and length were ascertained using the Actiwatch 2 Mini-Mitter, while subjective sleep was measured using the Pittsburgh Sleep Quality Index. Memory was indexed by tests of retrospective memory (Hopkins Verbal Learning Test - Revised), working memory (n-back, 2-back accuracy) and prospective memory (a habitual button pressing task). Compared with normative data, overall performance on retrospective memory function was within the average range. Hierarchical regression was used to determine whether objective or subjective measures of sleep predicted memory performances after controlling for demographics, health and mood. After controlling for confounds, actigraphic sleep indices (greater wake after sleep onset, longer sleep-onset latency and longer total sleep time) predicted poorer retrospective (∆R(2)  = 0.05, P = 0.016) and working memory (∆R(2)  = 0.05, P = 0.047). In contrast, subjective sleep indices did not significantly predict memory performances. In community-based older adults, objectively-measured, habitual sleep indices predict poorer memory performances. It will be important to follow the sample longitudinally to determine trajectories of change over time.

Mild traumatic brain injury in older adults: early cognitive outcome.

Severe traumatic brain injury (TBI) in older age is associated with high rates of mortality. However, little is known about outcome following mild TBI (mTBI) in older age. We report on a prospective cohort study investigating 3 month outcome in older age patients admitted to hospital-based trauma services. First, 50 mTBI older age patients and 58 orthopedic controls were compared to 123 community control participants to evaluate predisposition and general trauma effects on cognition. Specific brain injury effects were subsequently evaluated by comparing the orthopedic control and mTBI groups. Both trauma groups had significantly lower performances than the community group on prospective memory (d=0.82 to 1.18), attention set-shifting (d=-0.61 to -0.69), and physical quality of life measures (d=0.67 to 0.84). However, there was only a small to moderate but non-significant difference in the orthopedic control and mTBI group performances on the most demanding task of prospective memory (d=0.37). These findings indicate that, at 3 months following mTBI, older adults are at risk of poor cognitive performance but this is substantially accounted for by predisposition to injury or general multi-system trauma.

Assessing prospective memory in older age: the relationship between self-report and performance on clinic-based and naturalistic tasks.

This investigation assessed the relationship between subjective self-reports and objective measures of prospective memory with forty-eight healthy, community-dwelling older-adults (> 65 years). The Prospective and Retrospective Memory Questionnaire provided the self-report data, the Cambridge Prospective Memory Test was used as a clinic-based test, and the Telephone Task (telephoning the examiner at irregular, pre-scheduled times across one week) was used as a naturalistic measure. The self-reported difficulties were negatively associated with performance on the naturalistic task, r (41) = -0.341, p = <0.05, but not the clinic-based task. Performance tasks (clinic-based and naturalistic) were moderately associated, r (41) = 0.312, p = <0.05. Tests of retrospective memory (delayed recall) and executive function (attention set-shifting) did not individually predict performance on any of the prospective memory measures. Incorporating naturalistic probes of prospective memory performance into a clinical assessment may allow insight into the experience of prospective memory challenges in older-age clients.

Pre-Test Experience and Memory Performance in Older Adults: The Impact of Test Anxiety and Self-Efficacy.

OBJECTIVE: The objective of this paper is to investigate the role of test anxiety and memory self-efficacy on memory performances in older adults. METHOD: One hundred cognitively normal, community-dwelling older adults aged 65+ participated used in this experimental study. Participants completed baseline evaluations (including pre-test anxiety) prior to being assigned to one of two experimental conditions in which they experienced either success or failure on a verbal test. They subsequently completed post-test anxiety ratings, a measure of memory self-efficacy (Memory Self-Efficacy Questionnaire), and standardized tasks of working memory and verbal episodic memory. RESULTS: Following experimental manipulation, participants in the pre-test failure condition demonstrated higher anxiety and lower memory performances. Hierarchical regression revealed that change in anxiety from pre-test to post-test predicted memory performances and mediation analyses demonstrated that these effects were explained by lower memory self-efficacy. CONCLUSIONS: For older adults, experiencing test failure prior to memory testing may result in increased test anxiety and lower memory self-efficacy leading to poorer memory performance. This has implications for diagnostic cognitive assessment for older people.

Cognitive performance in older adults at three months following mild traumatic brain injury.

Introduction: In the context of limited research assessing outcomes following mild traumatic brain injury (mTBI) in older adults, this study evaluated cognitive outcomes through prospective memory, and expected that performance of an older mTBI group (≥65 years) would be lower compared to orthopedic and community controls. The study also explored whether cognitive resources (retrospective memory, executive function) moderated any association between presenting Glasgow Coma Scale (GCS) and prospective memory.Method: At three-months post-injury, a mTBI group (n = 39), an orthopedic control group (n = 63), and a community control group (n = 46) completed a neuropsychological assessment, including (i) prospective memory, using a standardized paper-and-pencil task (Cambridge Prospective Memory Test), an augmented reality task and a naturalistic task, and (ii) standardized measures of retrospective memory (Hopkins Verbal Learning Test) and executive function (Trail Making Test). Group performances were compared, and bootstrapped moderation analyses evaluated the role of cognitive resources in the relationship between GCS and prospective memory outcome.Results: The mTBI group, as compared to community controls, performed significantly lower on the augmented reality task (d = -0.64 to d = -0.79), and there was a small-moderate but non-significant effect (d = -0.45) on the naturalistic task. There were no differences between the mTBI group and orthopedic controls. Retrospective memory was a unique predictor of the augmented reality task (B = 1.83) and moderated the relationship between presenting GCS and the naturalistic task (B = -5.60). Executive function moderated the association between presenting GCS and augmented reality (B = -1.13) and naturalistic task (B = -1.57).Conclusions: At three-months post-mTBI, older adults are at risk of poor cognitive performance; and the relationship between GCS and prospective memory can be moderated by cognitive resources. Further follow-up is indicated to determine whether impairments resolve or persist over time.

Social support moderates the effect of stress on the cortisol awakening response in dementia family caregivers.

Dementia caregiving has been associated with a range of adverse effects on the physical health of the caregiver. However, the specific mechanisms underlying the relationship between dementia caregiver stress and ill health remain unclear. The aim of this study was to investigate, using available prospective data, the relationship between perceived stress (burden) and pre-clinical indices of ill-health (cortisol awakening response and secretory immunoglobulin A) amongst dementia caregivers. The potential moderating effect of social support on the perceived stress-physiological stress/health relationship was also explored. Participants (N = 31) were caregivers of community-dwelling older adults living with dementia who were enroled in a psychoeducation support program and provided data (study questionnaire and saliva samples) at two timepoints (T1 and T2), 10 weeks apart. Hierarchical regressions were used to determine if changes in stress and social support predicted change in each of the physiological outcomes. Findings indicate that caregivers with more hours of care at T1, or with greater satisfaction with social support, were more likely to exhibit an adaptive cortisol awakening response at T2. Moreover, social support was found to buffer the effect of caregiver stress and hours of caregiving on the cortisol awakening response. Implications for future interventions targeting caregiver health are discussed.

Learning and memory in amnestic mild cognitive impairment: contribution of working memory.

In addition to deficits in delayed recall, recent research suggests that participants with amnestic mild cognitive impairment (aMCI) demonstrate diminished use of strategic encoding strategies during learning. Few studies have explored the cognitive mechanisms underlying this deficit. The aim of this study was to investigate in aMCI whether components of working memory (executive attention--attention set-shifting, dividing and focusing attention; and episodic buffer functions--strategic retrieval and manipulation of information) predict strategic encoding strategies during learning (semantic clustering). Thirty-three participants with aMCI and 33 healthy older adults (HOA) were administered neuropsychological tests assessing word-list learning and working memory. The aMCI group demonstrated significant impairment in acquisition, retrieval of information, and decreased use of semantic clustering strategies. Use of semantic clustering in the aMCI group was not predicted by measures of executive attention or phonemic verbal fluency, but was predicted by semantic verbal fluency performance. In the HOA group, semantic clustering was strongly related to semantic verbal fluency. These findings suggest that in aMCI, diminished strategic encoding strategies during learning (semantic clustering) is selectively related to the strategic function of the episodic buffer, but only when in interaction with the manipulation and retrieval of semantic associations.

Who benefits from cognitive intervention in older age? The role of executive function.

Objective: In the context of the positive impact of cognitive interventions for age-related memory concerns, clinicians are seeking information about variables that predict optimum client response. In this study of older adults, the aim was to investigate baseline predictors of gain in memory performance, i.e. prospective memory, following a memory intervention.Methods: One hundred and one healthy older adults (H0A) and 73 older people with amnestic mild cognitive impairment (aMCI) were evaluated at 6-months after participating in a 6-week memory group intervention (LaTCH). The outcome measure was a clinic-based prospective memory task. Baseline predictors included demographic variables (age, gender, education), baseline prospective memory, and cognitive resources (retrospective memory, executive function).Results: Thirty percent of the HOA and 16% of the aMCI cohorts demonstrated reliable training effects on prospective memory test performance at 6-month assessment. Through hierarchical regressions in the HOA cohort, executive function (working memory, attention set shifting) rather than retrospective memory was the best predictor of change in prospective memory. Moderated regression did not demonstrate any interactions between retrospective memory and executive function. For the memory impaired cohort (aMCI), better baseline retrospective memory predicted greater gain in prospective memory but only when executive function was also high.Conclusions: Memory groups can improve performance on clinic-based prospective memory tests in older people with concerns about memory performance, suggesting the value of further translation studies to demonstrate functional real-world gains and quality of life improvement after training. These interventions may be especially effective for those older people with better executive function (working memory, attention set shifting).

Predictors of Long-Term Improvement in Subjective Everyday Memory Following a Memory Group Program for Older Adults.

Objective: The present study aimed to examine predictors of improvement in subjective everyday memory ability 5 years following participation in a group cognitive-behavioral memory intervention for community-living older adults, the La Trobe and Caulfield Hospital (LaTCH) Memory Group program. Method: Participants were 61 healthy older adults and data were analyzed using one-way repeated measures analysis of variance (ANOVA), hierarchical regression, and moderator analyses. Results: Although the group as a whole did not show significant gains in subjective memory ability following the intervention, greater gains in subjective memory ability were associated with poorer baseline associative memory, better baseline cognitive flexibility, and more subjective memory concerns prior to intervention. There was no interaction between the cognitive predictors and subjective memory concerns in predicting gains in subjective memory ability. Discussion: Differential benefits for more cognitively flexible individuals may derive from a greater capacity to engage skillfully in the expectancy modification aspects of the program.

Bridging the gap between clinical trials and community care: Translating a memory group for older people with mild cognitive impairment into a community-based organisation.

OBJECTIVES: Older people with mild cognitive impairment (MCI) are seeking interventions for maintaining independence. This study investigates the feasibility of translating a research-evaluated memory group (LaTCH) into a community-based organisation by evaluating the experiences of clients and trained staff. METHODS: Dementia Australia staff trained as facilitators of memory groups for 274 people with MCI and families. Clients and staff were interviewed regarding experiences from group participation. RESULTS: Clients and staff reported benefits of shared experience through group participation, leading to greater use of compensatory strategies. Staff observed client improvement in memory-related self-confidence, thereby reducing anxiety and increasing re-engagement in life activities. In their own professional roles, staff reported increased self-efficacy, leading to greater role satisfaction. Several challenges in running and sustaining the program were also identified. CONCLUSIONS: Memory group interventions can be feasibly delivered in a community setting and increase service access opportunities for older people with memory problems.

Naturalistic Measurement of Sleep in Older Adults with Amnestic Mild Cognitive Impairment: Anxiety Symptoms Do Not Explain Sleep Disturbance.

BACKGROUND: Sleep disturbance is prevalent in Alzheimer's disease (AD). In amnestic mild cognitive impairment (aMCI), the preclinical stage of AD, deterioration in sleep quality has also been reported. Consensus is lacking, however, regarding what aspects of sleep are characteristically affected, whether the setting of the sleep recordings impacts these findings, and whether anxiety may account for the differences. OBJECTIVE: The current study aimed to address these knowledge gaps by obtaining comprehensive sleep measurement in aMCI within a naturalistic environment using in-home sleep recordings. METHODS: 17 healthy older adults and twelve participants with aMCI wore an actiwatch for two weeks to objectively record habitual sleeping patterns and completed two nights of in-home polysomnography. RESULTS: In aMCI, habitual sleep disturbances were evident on actigraphy including greater wake after sleep onset (p = .012, d = 0.99), fragmentation (p = .010, d = 1.03), and time in bed (p = .046, d = .76). Although not statistically significant, there was a large group effect on polysomnography with aMCI demonstrating less slow-wave-sleep than controls (p >.05, d = .0.83). Anxiety did not mediate the relationship between the group and sleep in this small study. CONCLUSIONS: The results indicate that people with aMCI have poorer quality sleep than healthy controls, as indicated by greater sleep disruption and less slow-wave sleep, even in naturalistic settings. Additionally, anxiety symptoms do not mediate the relationship. Therefore, this research supports the view that sleep disturbance is likely to be indicative of neuropathological changes in aMCI rather than being attributed to psychological factors.

Performance of everyday actions in mild Alzheimer's disease.

Early neuropsychological deficits associated with mild Alzheimer's disease (AD) have been characterized as memory deficits and impaired executive function or attention. The functional impact of early impairment was investigated by evaluating performance of everyday actions in older adults with mild AD (n = 15) as compared with healthy age-matched controls (n = 16). Everyday actions were familiar activities, for example, making a cup of tea, but were varied in complexity (simple, complex) and were performed under varied attention demand (single task, dual task). Although both participant groups responded to increasing task complexity by making more errors, the AD group made more errors under dual-task conditions regardless of the complexity of the task. Furthermore, a task requiring strategic retrieval of semantic information from long-term memory and manipulation of attention online (category fluency) was able to account for a large proportion of the group-related variance in everyday task performance. Results are discussed in relation to the role of components of working memory in performance of everyday actions in mild AD.