Evaluating different aspects of prospective memory in amnestic and nonamnestic mild cognitive impairment

Investigating the relationship between periodontitis and specific memory processes in the search for cognitive markers of Alzheimer's disease risk

The spontaneous retrieval deficit (SRD) hypothesis argues that individuals in the preclinical stages of Alzheimer's disease (AD) are particularly impaired in spontaneous retrieval, which manifests in reduced mind-wandering. Our main purpose was to provide novel evidence to support the SRD hypothesis by investigating, for the first time, the relationship between mind-wandering and periodontitis, the latter being the risk factor for AD. The second objective was to address the lack of deeper understanding of the relationship between oral health and specific cognitive abilities by investigating whether periodontitis would be primarily associated with memory. Sixty community-dwelling dementia-free older adults completed neuropsychological tests that focused on various cognitive abilities and a computerised task, during which mind-wandering was evaluated. Periodontal health was assessed subjectively, and through an oral examination by a qualified dentist that focused on visible periodontitis-related changes in gingival tissues and the number of periodontitis bacteria. In line with our predictions, objective and subjective symptoms of poorer periodontal health were associated with less mind-wandering, providing further support for the SRD hypothesis. Again in line with predictions, poorer periodontal health was associated with worse episodic memory, with no relationship between periodontitis and the measure targeting various cognitive abilities, from which memory was excluded.

A Multicomponent Cognitive Intervention May Improve Self-Reported Daily Function of Adults With Subjective Cognitive Decline

IMPORTANCE

Limited evidence exists to support cognitive intervention improving the daily function of adults with subjective cognitive decline (SCD).

OBJECTIVE

To examine the preliminary efficacy of a group-based multicomponent cognitive intervention that integrates Lifestyle Redesign® (LR) techniques.

DESIGN

Single-arm two-period crossover trial; 16-wk waiting period, 16-wk intervention, and 16-wk follow-up.

SETTING

Memory clinic in a medical center, Taiwan.

PARTICIPANTS

Purposive sample of adults ages >55 yr with SCD.

INTERVENTION

Sixteen 1.5-hr weekly multicomponent sessions of cognitive training, cognitive rehabilitation, psychological intervention, and lifestyle intervention.

OUTCOMES AND MEASURES

Primary outcomes were (1) self-reported daily function, measured with the Activities of Daily Living Questionnaire (ADLQ) and Cognitive Failure Questionnaire; (2) performance-based daily function, measured with the Brief University of California San Diego Performance-Based Skills Assessment-Traditional Chinese Version; and (3) functional cognition, measured with the Contextual Memory Test (CMT) and Miami Prospective Memory Test. Secondary outcomes included cognitive functions, anxiety, and depression.

RESULTS

Seventeen participants completed the intervention; 4 missed the follow-up. The generalized estimating equations model showed significant changes from baseline to pretest (control) and pretest to posttest (intervention) on the ADLQ (p = .014) and CMT-delayed (p = .003). Effects remained at the 16-wk follow-up. After adjusting for the effects of covariates, the self-reported daily function of participants ages ≤ 63 yr improved more than that of other participants (p = .003).

CONCLUSIONS AND RELEVANCE

Multicomponent cognitive interventions integrating LR techniques may improve self-reported daily function and context-dependent memory function of adults with SCD, with efficacy sustained at follow-up. What This Article Adds: A group-based multicomponent cognitive intervention consisting of cognitive training, cognitive rehabilitation, psychoeducation, and lifestyle intervention may provide benefits for the daily function and cognitive function of adults with SCD.

Prospective memory in multiple sclerosis: clinical utility of the Miami Prospective Memory Test

Objective: Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system that frequently affects cognition. Persons with MS (PwMS) complain of difficulties with prospective memory (PM), the capacity to remember to perform an intended action at the appropriate moment in the future. The objective of this study was to assess the clinical utility of the Miami Prospective Memory Test (MPMT) in detecting PM deficits in MS. The test is brief, easy to administer and accessible, and allows direct comparison between scores on event- and time-based conditions. A secondary objective was to examine the relationship between PM performance and cognitive functioning. Method: Eighty-four PwMS between 27 and 78 years old were compared to 50 age-, sex- and education-matched healthy adults on the MPMT. Results: Time-based (TB) scores, but not event-based (EB) scores, were significantly lower in PwMS than in healthy adults. The MPMT showed good internal consistency, and correlations were found with disability assessed by the Expanded Disability Status Scale (EDSS). PM was also correlated with memory and executive/attention functioning. Conclusions: This study supports the clinical utility of the MPMT in assessing the presence of PM deficits in PwMS especially under TB constraints.

Associations Between Handgrip Strength and Dementia Risk, Cognition, and Neuroimaging Outcomes in the UK Biobank Cohort Study

IMPORTANCE

The associations between muscle strength and cognitive outcomes have sparked interest in interventions that increase muscle strength for prevention of dementia, but the associations between muscle strength and cognitive aging are unclear, particularly among middle-aged adults.

OBJECTIVE

To evaluate the association between handgrip strength (HGS) and dementia, reduced cognition, and poorer neuroimaging outcomes in a UK population of middle-aged adults.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study evaluated UK Biobank participants aged 39 to 73 years enrolled from 2006 to 2010 with measured HGS and prospectively followed up for dementia diagnosis. Data were analyzed from October 2021 to April 2022.

EXPOSURES

HGS assessed in both hands via dynamometer.

MAIN OUTCOMES AND MEASURES

Outcomes included cognitive test scores (fluid intelligence and prospective memory), brain magnetic resonance imaging measures (total brain volume, white matter hyperintensity, and hippocampal volume), and incident dementia (all-cause, vascular, and Alzheimer disease [AD] from primary care, hospital, or death records) over a median (IQR) of 11.7 (11.0-12.4) years of follow-up. Mixed-effects linear and logistic regressions and Cox proportional-hazard models were used to estimate associations, stratified by gender and adjusted for covariates. Estimates are presented per 5-kg decrement in HGS. To evaluate reverse causation, we assessed whether a polygenic risk score for AD is associated with HGS.

RESULTS

A subsample of 190 406 adult participants in the UK Biobank (mean [SD] age, 56.5 [8.1] years; 102 735 women [54%]) were evaluated. A 5-kg decrement in HGS was associated with lower fluid intelligence scores in men (β, -0.007; 95% CI, -0.010 to -0.003) and women (β, -0.04; 95% CI, -0.05 to -0.04. A 5-kg decrement in HGS was associated with worse odds of correctly responding to a prospective memory task for men (odds ratio, 0.91; 95% CI, 0.90 to 0.92) and women (odds ratio, 0.88; 95% CI, 0.87 to 0.90). A 5-kg decrement in HGS was associated with greater white matter hyperintensity volume in men (β, 92.22; 95% CI, 31.09 to 153.35) and women (β, 83.56; 95% CI, 13.54 to 153.58). A 5-kg decrement in HGS was associated with incident dementia for men (hazard ratio, 1.20; 95% CI, 1.12 to 1.28) and women (hazard ratio, 1.12; 95% CI, 1.00 to 1.26). The AD genetic risk score was not significantly associated with HGS.

CONCLUSIONS AND RELEVANCE

These findings suggest that HGS is associated with measures of neurocognitive brain health among men and women and they add to a growing body of research indicating that interventions designed to increase muscle strength, particularly among middle-aged adults, may hold promise for the maintenance of neurocognitive brain health.

Cultural factors related to neuropsychological performance and brain atrophy among Hispanic older adults with amnestic Mild Cognitive Impairment (aMCI): A pilot study

OBJECTIVES

This study examined the association of cultural factors and literacy to neuropsychological performance and measures of regional brain atrophy among Hispanic elders diagnosed with amnestic Mild Cognitive Impairment (aMCI).

METHOD

Acculturation and literacy levels were measured among 45 subjects tested in Spanish; their primary language. Scores for measures of memory, executive functioning, and verbal fluency, as well as volumetric analysis of MRI scans of left hemisphere structures commonly affected by Alzheimer's disease (AD) were examined. Linear regression models were employed to examine the association of acculturation and literacy to neuropsychological performance and MRI measures.

RESULTS

After controlling for age, higher literacy levels were associated with better performance on phonemic verbal fluency (r = 0.300, p < .05), while higher levels of acculturation to the U.S. was associated with poorer performance on category verbal fluency (r = 0.300, p < .05). There was a significant inverse relationship after controlling for age between literacy and the left entorhinal cortex (r = -0.455, p < .05), left precuneus (r = -0.457, p < .05), and left posterior cingulate (r = -0.415, p < .05).

CONCLUSIONS

Results of the current pilot study indicate that high acculturation to the U.S. among aMCI immigrants from Latin-American countries may hinder performance on verbal learning measures when they are administered in one's primary language. Moreover, in this cohort, a higher literacy level, which is indicative of greater cognitive reserve, was associated with better performance in language measures, but with greater atrophy in brain regions susceptible to neurodegenerative disease. These preliminary findings should be further examined among larger cohorts and using more diverse measures, which capture other cultural constructs.

Social Support Buffers Against Cognitive Decline in Single Mild Traumatic Brain Injury With Loss of Consciousness: Results From the Canadian Longitudinal Study on Aging

OBJECTIVES

We investigated rates of cognitive decline at 3-year follow-up from initial examination in people reporting mild traumatic brain injury (mTBI) with loss of consciousness (LOC) more than a year prior to initial examination. We examined the role of social support as predictor of preserved cognitive function in this sample.

METHOD

Analyses were conducted on 440 participants who had self-reported LOC of <1 min, 350 with LOC of 1-20 min, and 10,712 healthy controls, taken from the Canadian Longitudinal Study on Aging (CLSA), a nationwide study on health and aging.

RESULTS

People who reported at baseline that they had experienced mTBI with LOC of 1-20 min more than a year prior were 60% more likely to have experienced global cognitive decline than controls at three-year follow-up. Cognitive decline was most apparent on measures of executive functioning. Logistic regression identified increased social support as predictors of relatively preserved cognitive function.

DISCUSSION

mTBI with longer time spent unconscious (i.e., LOC 1-20 min) is associated with greater cognitive decline years after the head injury. Perceived social support, particularly emotional support, may help buffer against this cognitive decline.

Multi-component cognitive intervention for older adults with mixed cognitive levels: implementation and preliminary effectiveness in real-world settings

BACKGROUND

In most controlled studies of multi-component cognitive intervention, participants' cognitive levels are homogenous, which is contrary to real-world settings. There is a lack of research studying the implementation of evidence-based cognitive intervention in communities. This study describes the implementation and preliminary effectiveness of a Multi-component Cognitive Intervention using Simulated Everyday Tasks (MCI-SET) for older adults with different cognitive levels in real-world settings.

METHODS

Single group, pre-intervention assessment, post-intervention assessment, and 3-month follow-up research design. MCI-SET consists of 12 two-hour weekly sessions that include motor-cognitive tasks, cognitive training, and cognitive rehabilitation. One hundred and thirty participants, > = 65 and frail, dependence on > = one instrumental daily activity, or with confirmed dementia, from eight community centers were included. The primary outcome is general cognition (Montreal Cognitive Assessment-Taiwan, MoCA-T). Secondary outcomes are memory (Miami Prospective Memory Test, Digits Forward, Digits Backward), attention (Color Trail Test-Part 1), executive function (Color Trail Test-Part 2), and general function (Kihon Checklist-Taiwan).

RESULTS

Pre-intervention workshop for group leaders, standardized activity protocols, on-site observation, and ten weekly conferences were conducted to ensure implementation fidelity. MCI-SET had an 85% retention rate and 96% attendance rate. The participants had a mean age of 78.26 ± 7.00 and a mean MoCA-T score of 12.55 ± 7.43. 73% were female. General cognition (Hedges' g = 0.31), attention (Hedges' g = 0.23), and general function (Hedges' g = 0.31), showed significant post-intervention improvement with small effect size. Follow-ups showed maintained improvement in general cognition (Hedges' g = 0.33), and delayed effect on attention (Hedges' g = 0.20), short-term memory (Hedges' g = 0.38), and executive function (Hedges' g = 0.40). Regression analysis indicated that the intervention settings (day care centers vs neighborhood centers), the pre-intervention cognitive levels, and the pre-intervention general function of the participants were not associated with the outcomes.

CONCLUSIONS

MCI-SET is feasible and can improve the cognitive skills and general functions of older adults with heterogeneous cognitive skills or disabilities. It is essential to tailor programs to fit the interests of the participants and the culture of local communities. Group leaders must also have the skills to adjust the cognitive demands of the tasks to meet the heterogeneous cognitive levels of participants.

TRIAL REGISTRATION

This study was retrospectively registered at clinicaltrials.gov (Identifier: NCT04615169 ).

Disrupted anterior and posterior hippocampal structural networks correlate impaired verbal memory and spatial memory in different subtypes of mild cognitive impairment

BACKGROUND AND PURPOSE

The anterior and posterior hippocampal networks represent verbal and spatial memory, respectively, and may play different roles in the pathological mechanism of amnestic mild cognitive impairment (aMCI) and non-amnestic MCI (naMCI), which has not been explored.

METHODS

A total of 990 older adults with 791 normal controls (NCs) (65 ± 6 years, 502 women), 140 aMCI (66 ± 7 years, 84 women) and 59 naMCI (66 ± 7 years, 38 women) were included. A multivariate method, partial least squares, was used to assess the structural covariance networks of the anterior hippocampus (aHC) and posterior hippocampus (pHC), and their relationships with verbal memory and spatial memory in the three groups.

RESULTS

Three aHC and pHC structural covariance network patterns emerged: (1) the age pattern; (2) the specific aMCI pattern; and (3) the spatial memory pattern. Furthermore, aMCI patients had more extensive and severe damage in the three patterns, and correlated with greater decline in verbal memory, which was mainly characterized by the aHC network.

CONCLUSIONS

The aMCI and naMCI showed different patterns and damage in the structural covariance networks, and functional segregation of the aHC and pHC networks still exists in the process of pathological aging. A potential neural explanation is provided for the conversion of aMCI and naMCI into different types of dementia in the future.

Learning-Enabled Robotic Assistive Support: Understanding Older Adult Opinions and Comparing Them to Younger Adult Opinions

Background

As older adults age, they may require assistance completing activities of daily living (ADLs). Robotic assistance can offset healthcare costs and allow older adults to preserve their autonomy. Younger adults are often involved in the design and purchase of these robotic technologies, and must take into account the needs and expectations of the target population (i.e., older adults) to create a robot that the end-user will adopt.

Research Aim/Questions

This study evaluated the opinions of both younger and older adults regarding the design and performance of the Robot Activity Support (RAS) system. It is important to understand points of agreement and divergence between these populations' perspectives so that effective robotic aids are created for older adults.

Methods

Fifty-two younger and older adults completed three scripted tasks with the RAS robot in a smart home environment. Each participant made task errors to cue the robot to offer help via three prompt modalities (guide to the object, video of forgotten step, and video of the full task). After interacting with the robot, participants completed questionnaires to evaluate their opinions of and satisfaction with the robot.

Results

There were no differences between younger and older adults' perceptions of the robot across a variety of factors (e.g., likability, cognitive demand), with both age groups expressing generally neutral opinions. Both groups rated the Full Video prompt as least helpful, effective, and liked. Participants recommended the robot's response accuracy, movement speed, alerting style and system flexibility be improved. Younger adults overestimated how much older adults would want a robot like this.

Conclusions

This study underscores the importance of testing technology with the end-user, as older adults were less interested in having a similar robot in their home than younger counterparts expected. Future studies will show if older adults' opinions can be improved after making the recommended changes.

Associations between performance-based and self-reported prospective memory, impulsivity and encoding support

Prospective memory (PM) is the ability to execute future intended actions and may be negatively affected by impulsivity. The current study aimed to address questions on (1) relationships of PM with facets of impulsivity; (2) psychometric properties of a PM task, in particular convergent validity with self-reported PM; and (3) whether external support of the encoding process would improve PM or affect relationships with impulsivity. 245 participants performed the experiment online. Participants completed either a baseline version of the task, which combined blocks of an ongoing working memory task with PM trials involving a varying stimulus requiring an alternative response; or a version that provided external support of encoding by requesting that participants visualize and execute the intended prospective action before each block. The Prospective-Retrospective Memory Questionnaire (PRMQ) and Short Version of the UPPS-P Impulsive Behavior Scale (SUPPS) were used to assess self-reported prospective memory and facets of impulsivity. Reliability of PM performance was good and remained acceptable even with the exclusion of participants with low scores. PM performance was associated with self-reported PM, explaining variance in addition to that explained by working memory performance. PM performance was also negatively associated with impulsivity, in particular sensation seeking and positive urgency, but only in the baseline task. Support did not cause overall improvements in performance. In conclusion, results provided further evidence for a relationship between facets of impulsivity and PM. PM as assessed via the current task has good psychometric properties.

An exploration of prospective memory components and subtasks of the Memory for Intentions Test (MIST)

Introduction: Prospective Memory (PM), the ability to execute future intentions, decreases with age and memory-related disorders and may be an early predictor of dementia. The Memory for Intentions Test (MIST) allows the assessment of multiple aspects of PM using a range of subtasks. The current study evaluated and explored a Portuguese version of the MIST and its subtasks.Method: Forty-one patients with Mild Cognitive Impairment (MCI) and forty healthy participants performed the MIST, neuropsychological tests and questionnaires. Analyses were performed testing relationships between MCI and PM components of the MIST, and differences between subtasks of the test were explored.Results: Reliability of the PM component was acceptable within the patient group, but not within the control group. PM components were significantly lower in the MCI patients, but this effect was dependent on subtasks. Groups differed most strongly at shorter intervals. PM scores predicted MCI status. Correlations were found between PM components and cognitive functioning scales.Conclusions: The Portuguese version of the MIST seems suitable for use in clinical practice and research. MCI is differentially related to different PM components and subtasks of the MIST.

Mild cognitive impairment and prospective memory: translating the evidence into neuropsychological practice

OBJECTIVE

There has been a recent rapid development of research characterizing prospective memory performance in mild cognitive impairment (MCI) in older age. However, this body of literature remains largely separated from routine clinical practice in neuropsychology. Furthermore, there is emerging evidence of effective interventions to improve prospective memory performance. Therefore, our objective in this article was to offer a clinical neuropsychological perspective on the existing research in order to facilitate the translation of the evidence-base into clinical practice.

METHOD

By conducting a critical review of the existing research related to prospective memory and MCI, we highlight how this data can be introduced into clinical practice, either within diagnostic assessment or clinical management.

CONCLUSIONS

Prospective memory is impaired in older adults with MCI, with a pattern of performance that helps with differential diagnosis from healthy aging. Clinical neuropsychologists are encouraged to add prospective memory assessment to their toolbox for diagnostic evaluation of clients with MCI. Preliminary findings of prospective memory interventions in MCI are promising, but more work is required to determine how different approaches translate to increasing independence in everyday life.

Performance-based and Observational Assessments in Clinical Trials Across the Alzheimer's Disease Spectrum

Assessment of the earlier stages of Alzheimer's disease requires different strategies than those previously developed for fully syndromal Alzheimer's disease . This challenge is further magnified in very early stages, where symptomatology may be minimal and functional deficits very subtle to absent. This paper reviews strategies for performance-based assessment of the early stages of Alzheimer's disease, including assessments of cognition, functional capacity, and social cognition. Meetings with an International Society for CNS Clinical Trials and Methodology working group served as the basis for this paper and its companion. The current state of the art of detection and staging-oriented assessments is presented, and information is provided regarding the practicality and validity of these approaches, with a special focus on their usefulness in clinical trials for new medication development.

Clinical Utility of the Envelope Task in Mild Cognitive Impairment and Dementia

Objective: Prospective memory (PM) is a cognitive function defined as the ability to perform an intention at an appropriate moment in the future. In the aging population, PM is essential for maintaining independent daily living. Introduced as a simple and quick way to assess PM in clinical settings, the envelope task has to date received very limited empirical and practical interest. Methods: The present study investigated the task’s clinical utility in detecting PM impairment in a sample composed of 49 healthy older adults (OA), 41 patients with Alzheimer’s disease, and 64 individuals with amnestic and nonamnestic mild cognitive impairment (MCI) of heterogeneous etiology: 17 of idiopathic nature, 20 presenting an idiopathic rapid-eye movement sleep behaviour disorder, and 27 patients diagnosed with idiopathic Parkinson’s disease. Results: The envelope task was highly sensitive and specific in discriminating Alzheimer’s disease patients from OA. Although it was specific in distinguishing MCI individuals from OA, its sensitivity was modest, especially in patients presenting a nonamnestic MCI subtype. Conclusions: Given its high specificity and simple low-cost administration procedure, the envelope task is a promising instrument for clinicians who seek to rapidly assess PM impairment in their daily practice.