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

Just as expected? Older adults' aging expectations are associated with subjective cognition

OBJECTIVES

This study investigated the relationship between older adults' expectations regarding aging and subjective cognition. Specifically, we examined whether the three domains of aging expectations (physical health, mental health, and cognitive function) were associated with two aspects of subjective cognition: current subjective cognition and subjective cognitive decline (SCD).

METHOD

An online survey was conducted among U.S. adults aged 65-90 (N = 581; Mage=71.4, SD ± 4.81; 51% female). Measures included the 12-item Expectations Regarding Aging scale, the 8-item PROMIS Cognitive Abilities scale (current subjective cognition), and the 12-item Everyday Cognition scale (SCD). We used generalized linear models to examine associations between overall aging expectations and its three domains with current subjective cognition ratings and SCD.

RESULTS

We found that more positive expectations regarding physical health, mental health, and cognitive function in aging were associated with higher ratings of current subjective cognition as well as lower SCD. The magnitude of effects across aging expectations domains were similar for both aspects of subjective cognition.

CONCLUSION

Aging expectations are malleable and influence an individual's perceptions of their cognitive functioning. Modifying older adults' aging expectations could support healthier cognitive aging through increased awareness and accurate assumptions about the aging process.

Cognitive impairment and self-reported health outcomes among older adults: Longitudinal evidence from Australia

BACKGROUND

Australia's population is ageing, with forecasts indicating that individuals aged 65 years and over will account for >20 % of the total population by 2066. Ageing is strongly linked with a significant decrease in cognitive capabilities. This study aimed to explore the association between cognitive impairment and four types of health outcomes among older Australians.

METHODS

Data used for this study was collected from the Household, Income and Labour Dynamics in Australia (HILDA) Survey. The final analysis consisted of 11,146 person-year observations from 7035 unique individuals from Wave 2012 and Wave 2016, respectively. A longitudinal random-effects generalised least squares, and ordered logistic regression were used to analyse the association between cognitive impairment and health outcomes.

RESULTS

The study results suggest that cognitive impairment was negatively associated with general health, mental health, self-assessed health and health satisfaction. Older Australians with cognitive impairment scored lower on general health (β = -2.82, SE = 0.56), mental health (β = -2.93, SE = 0.53), self-assessed health (β = - 0.75, SE = 0.10), and health satisfaction (β = -0.19, SE = 0.09) compared to the counterparts without cognitive impairment. The heterogeneous results also showed cognitive impairment was associated with poor health outcomes across age groups.

CONCLUSION

This study found evidence that cognitive impairment is associated with poor health outcomes. To enhance the physical and mental health and well-being of older adults, the community, government and non-government organizations, and other stakeholders should prioritize routine healthcare prevention, targeted interventions, and treatment practices, particularly for individuals with or at risk of cognitive impairment.

Daily relationship satisfaction and markers of health: Findings from a smartphone-based assessment

Relationship satisfaction is associated consistently with better physical and mental health. Less is known about these associations in daily life, particularly the association between relationship satisfaction and cognitive health. This study examined the daily, within-person association between relationship satisfaction and subjective health markers, including cognitive health. Participants from the United States (N = 303; Mage = 51.71, SD = 7.32) in the Couples Healthy Aging Project (CHAP) completed assessments of relationship satisfaction and health markers every night for eight days. Multilevel modeling was performed by accounting for personal (sex, age, race, education), relational (relationship duration), and contextual (day in the study, weekend day) factors. Within-person, on days when participants were more satisfied with their relationship, they felt healthier, younger, more satisfied with their life, and more purposeful. They also reported a sharper mind, better memory, and clearer thinking; relationship satisfaction was unrelated to whether participants were bothered and disrupted by forgetting. Results indicated that a satisfying romantic relationship is closely associated with better physical, psychological, and cognitive health markers in daily life.

Association of Subjective Cognitive Concerns With Performance on Mobile App-Based Cognitive Assessment in Cognitively Normal Older Adults: Observational Study

Background

Subjective cognitive concerns (SCCs) may be among the earliest clinical symptoms of dementia. There is growing interest in applying a mobile app-based cognitive assessment to remotely screen for cognitive status in preclinical dementia, but the relationship between SCC and relevant mobile assessment metrics is uncertain.

Objective

This study aimed to characterize the relationship between SCC and adherence, satisfaction, and performance on mobile app assessments in cognitively unimpaired older adults.

Methods

Participants (N=122; Meanage=68.85 [SD 4.93] years; Meaneducation=16.85 [SD 2.39] years; female: n=82, 66.7%; White:n=106, 86.2%) completed 8 assessment days using Mobile Monitoring of Cognitive Change (M2C2), an app-based testing platform, with brief daily sessions within morning, afternoon, and evening time windows (24 total testing sessions). M2C2 includes digital working memory, processing speed, and episodic memory tasks. Participants provided feedback about their satisfaction and motivation related to M2C2 upon study completion. SCC was assessed using the Cognitive Function Instrument. Regression analyses evaluated the association between SCC and adherence, satisfaction, and performance on M2C2, controlling for age, sex, depression, and loneliness. Linear-mixed effects models evaluated whether SCC predicted M2C2 subtest performance over the 8-day testing period, controlling for covariates.

Results

SCC was not associated with app satisfaction or protocol motivation, but it was significantly associated with lower rates of protocol adherence (ß=-.20, P=.37, 95% CI -.65 to -.02). Higher SCC endorsement significantly predicted worse overall episodic memory performance (ß=-.20, P=.02, 95% CI -.02 to -.01), but not working memory or processing speed. There was a main effect of SCC on working memory performance at day 1 (estimate=-1.05, SE=0.47, P=.03) and a significant interaction between SCC and working memory over the 8-day period (estimate=0.05, SE=0.02, P=.03), such that SCC was associated with initially worse, then progressively better working memory performance.

Conclusions

SCCs are associated with worse overall memory performance on mobile app assessments, patterns of cognitive inefficiency (variable working memory), and mildly diminished adherence across an 8-day assessment period. Findings suggest that mobile app assessments may be sensitive to subtle cognitive changes, with important implications for early detection and treatment for individuals at risk for dementia.

Depressive Symptoms and Amyloid Pathology

Importance

Depressive symptoms are associated with cognitive decline in older individuals. Uncertainty about underlying mechanisms hampers diagnostic and therapeutic efforts. This large-scale study aimed to elucidate the association between depressive symptoms and amyloid pathology.

Objective

To examine the association between depressive symptoms and amyloid pathology and its dependency on age, sex, education, and APOE genotype in older individuals without dementia.

Design, Setting, and Participants

Cross-sectional analyses were performed using data from the Amyloid Biomarker Study data pooling initiative. Data from 49 research, population-based, and memory clinic studies were pooled and harmonized. The Amyloid Biomarker Study has been collecting data since 2012 and data collection is ongoing. At the time of analysis, 95 centers were included in the Amyloid Biomarker Study. The study included 9746 individuals with normal cognition (NC) and 3023 participants with mild cognitive impairment (MCI) aged between 34 and 100 years for whom data on amyloid biomarkers, presence of depressive symptoms, and age were available. Data were analyzed from December 2022 to February 2024.

Main Outcomes and Measures

Amyloid-β1-42 levels in cerebrospinal fluid or amyloid positron emission tomography scans were used to determine presence or absence of amyloid pathology. Presence of depressive symptoms was determined on the basis of validated depression rating scale scores, evidence of a current clinical diagnosis of depression, or self-reported depressive symptoms.

Results

In individuals with NC (mean [SD] age, 68.6 [8.9] years; 5664 [58.2%] female; 3002 [34.0%] APOE ε4 carriers; 937 [9.6%] had depressive symptoms; 2648 [27.2%] had amyloid pathology), the presence of depressive symptoms was not associated with amyloid pathology (odds ratio [OR], 1.13; 95% CI, 0.90-1.40; P = .29). In individuals with MCI (mean [SD] age, 70.2 [8.7] years; 1481 [49.0%] female; 1046 [44.8%] APOE ε4 carriers; 824 [27.3%] had depressive symptoms; 1668 [55.8%] had amyloid pathology), the presence of depressive symptoms was associated with a lower likelihood of amyloid pathology (OR, 0.73; 95% CI 0.61-0.89; P = .001). When considering subgroup effects, in individuals with NC, the presence of depressive symptoms was associated with a higher frequency of amyloid pathology in APOE ε4 noncarriers (mean difference, 5.0%; 95% CI 1.0-9.0; P = .02) but not in APOE ε4 carriers. This was not the case in individuals with MCI.

Conclusions and Relevance

Depressive symptoms were not consistently associated with a higher frequency of amyloid pathology in participants with NC and were associated with a lower likelihood of amyloid pathology in participants with MCI. These findings were not influenced by age, sex, or education level. Mechanisms other than amyloid accumulation may commonly underlie depressive symptoms in late life.

Trajectories of Cognitive Function and Predictors Among Older Adults in Korea for 8 Years: A National Panel Data Analysis

This study aims to examine the trajectory of older adults' cognitive function over time and identify its predictors. Based on the model of neuroplasticity and cognitive reserve, participants' general characteristics as well as their physical, mental, and social factors were included as predictors of cognitive function. A latent growth model analysis was used to examine the trajectory of cognitive function and its predictors. The analysis of the unconditional model revealed that older adults' cognitive function significantly decreased over time. The rate of cognitive decline was significantly related with age, current smoking status, depression scores, number of social activities, time spent in group cognitive activities, and number of individual cognitive activities. The findings identified predictors affecting initial cognitive function and the rate of cognitive decline in older adults. The rate of cognitive decline varies widely among individuals. Identifying these differences is essential for effectively tailoring interventions that address individual needs.

Diagnostic accuracy of the Montreal Cognitive Assessment in screening for cognitive impairment in initially hospitalized COVID-19 patients: Findings from the prospective multicenter NeNeSCo study

OBJECTIVE

This study aimed to investigate the prevalence and nature of cognitive impairment among severely ill COVID-19 patients and the effectiveness of the Montreal Cognitive Assessment (MoCA) in detecting it.

METHOD

We evaluated cognition in COVID-19 patients hospitalized during the first wave (March to June 2020) from six Dutch hospitals, nine months post-discharge, using a comprehensive multi-domain neuropsychological test battery. Test performance was corrected for sex, age, and education differences and transformed into z-scores. Scores within each cognitive domain were averaged and categorized as average and above (z-score ≥ -0.84), low average (z-score -1.28 to -0.84), below average (z-score -1.65 to -1.28), and exceptionally low (z-score < -1.65). Patients were classified with cognitive impairment if at least one domain's z-score fell below -1.65. We assessed the MoCA's accuracy using both the original cutoff (<26) and an "optimal" cutoff determined by Youden's index.

RESULTS

Cognitive impairment was found in 12.1% (24/199) of patients, with verbal memory and mental speed most affected (6.5% and 7% below -1.65, respectively). The MoCA had an area under the curve of 0.84. The original cutoff showed sensitivity of 83% and specificity of 66%. Using the identified optimal cutoff of <24, maintained sensitivity while improving specificity to 81%.

CONCLUSIONS

Cognitive impairment prevalence in initially hospitalized COVID-19 patients is lower than initially expected. Verbal memory and processing speed are primarily affected. The MoCA is a valuable screening tool for these impairments and lowering the MoCA cutoff to <24 improves specificity.

Unstable functional brain states and reduced cerebro-cerebellar modularity in elderly individuals with subjective cognitive decline

The preclinical stage of Alzheimer's Disease (AD) holds great potential for intervention, therefore, it is crucial to elucidate the neural mechanisms underlying the progression of subjective cognitive decline (SCD). Previous studies have predominantly focused on the neural changes in the cerebrum associated with SCD, but have relatively neglected the cerebellum, and its functional relationship with the cerebrum. In the current study, we employed dynamic functional connectivity and large-scale brain network approaches to investigate the pathological characteristics of dynamic brain states and cerebro-cerebellar collaboration between SCD (n = 32) and the healthy elderly (n = 29) using resting-state fMRI. Two-way repeated measures ANOVA and permutation t-tests revealed significant group differences, with individuals with SCD exhibiting shorter state duration and more frequent transitions between states compared to the healthy elderly individuals. Additionally, individuals with SCD showed lower levels of intracerebellar functional connectivity, but higher levels of cerebellar-cerebral functional integration. Furthermore, the hub nodes of the functional networks in SCD shifted between the cerebellum and cerebrum across different brain states. These findings indicate that SCD exhibits greater state instability but may compensate for the negative effects of early disease by integrating cerebellar and cerebral networks, thereby maintaining cognitive performance. This study enhances our theoretical understanding of cerebellar-cerebral relationship changes in the early stages of AD and provides evidence for early interventions targeting the cerebellum.

Analysis of factors affecting subjective cognitive decline in elderly hypertensive patients and the construction of a risk prediction model

Subjective cognitive decline (SCD) is more prevalent in the elderly Chinese population, and individuals with hypertension are at greater risk for cognitive impairment. The aim of this study was to investigate the prevalence and factors affecting SCD in elderly hypertensive patients and to develop a risk prediction model. This was a cross-sectional study of 1098 elderly hypertensive patients in a tertiary care hospital. The prevalence of SCD in elderly hypertensive patients was 45.2 %. Education level, exercise, disease duration, blood pressure grade, depression, nutrition, debility, and sleep disorders were influential factors. A prediction model was constructed using these factors. The internal validation AUROC is 0.877 and the external validation AUROC is 0.813. Calibration curves and DCA curves indicated that the prediction model was well fitted. The predictive model constructed in this study may be useful for clinical screening and the development of targeted intervention programs.

Research on the application of functional near-infrared spectroscopy in differentiating subjective cognitive decline and mild cognitive impairment

Introduction

Alzheimer's disease (AD) is a common neurological disorder. Based on clinical characteristics, it can be categorized into normal cognition (NC), subjective cognitive decline (SCD), mild cognitive impairment (MCI), and dementia (AD). Once the condition begins to progress, the process is usually irreversible. Therefore, early identification and intervention are crucial for patients. This study aims to explore the sensitivity of fNIRS in distinguishing between SCD and MCI.

Methods

An in-depth analysis of the Functional Connectivity (FC) and oxygenated hemoglobin (HbO) characteristics during resting state and different memory cognitive tasks is conducted on two patient groups to search for potential biomarkers. The 33 participants were divided into two groups: SCD and MCI.

Results

Functional connectivity strength during the resting state and hemodynamic changes during the execution of Verbal Fluency Tasks (VFT) and MemTrax tasks were measured using fNIRS. The results showed that compared to individuals with MCI, patients with SCD exhibited higher average FC levels between different channels in the frontal lobe during resting state, with two channels' FC demonstrating significant ability to distinguish between SCD and MCI. During the VFT task, the overall average HbO concentration in the frontal lobe of SCD patients was higher than that of MCI patients from 5 experimental paradigm. Receiver operating characteristic analysis indicated that the accuracy of the above features in distinguishing SCD from MCI was 78.8%, 72.7%, 75.8%, and 66.7%, respectively.

Discussion

fNIRS could potentially serve as a non-invasive biomarker for the early detection of dementia.

Stumbles, Gait, and Cognition: Risk Factors Associated with Falls in Older Adults with Subjective Memory Complaints

Falls are a public health problem, impacting quality of life, independence, and health costs. Subjective memory complaints (SMCs) and mild cognitive impairment (MCI) increase with age and may coexist. The risk of falls coinciding with SMCs is less understood. This study explored the risk factors associated with falls in adults with SMCs or MCI. A case-control study in adults over 50 was conducted. All participants underwent a neuropsychological assessment and a Timed Up and Go (TUG) test for gait analysis. Logistic regression calculated OR and p values, adjusting for demographic, clinical, cognitive, and gait variables. There was a total of 64 patients (47.06%) and 72 controls (52.94%). Fallers were older (70.76 ± 7.31) and had hypertension (29.63%), a history of stumbling (13.97%), slow TUG test performance (19.12%), and an asymmetric arm swing (19.85%). Fallers had lower verbal fluency (p = 0.043) and impairment on the Rey-Osterrieth figure copy (p = 0.047). Highest risk factors included female sex (OR 3.55, p = 0.006), older age (OR= 1.08, p = 0.006), hypertension (OR 3.33, p = 0.005), and stumbles (OR 5.65, p = 0.002). This study reconsiders clinical fall risk assessments in older adults with SMCs. Visuo-constructional abilities and executive dysfunction should be followed over time. Female sex, hypertension, and stumbles are risk factors. Integrated cognitive and motor assessments are crucial for detecting and proposing interventions for fall prevention in this population.

Delivery of Neuropsychological Interventions for Adult and Older Adult Clinical Populations: An Australian Expert Working Group Clinical Guidance Paper

Delivery of neuropsychological interventions addressing the cognitive, psychological, and behavioural consequences of brain conditions is increasingly recognised as an important, if not essential, skill set for clinical neuropsychologists. It has the potential to add substantial value and impact to our role across clinical settings. However, there are numerous approaches to neuropsychological intervention, requiring different sets of skills, and with varying levels of supporting evidence across different diagnostic groups. This clinical guidance paper provides an overview of considerations and recommendations to help guide selection, delivery, and implementation of neuropsychological interventions for adults and older adults. We aimed to provide a useful source of information and guidance for clinicians, health service managers, policy-makers, educators, and researchers regarding the value and impact of such interventions. Considerations and recommendations were developed by an expert working group of neuropsychologists in Australia, based on relevant evidence and consensus opinion in consultation with members of a national clinical neuropsychology body. While the considerations and recommendations sit within the Australian context, many have international relevance. We include (i) principles important for neuropsychological intervention delivery (e.g. being based on biopsychosocial case formulation and person-centred goals); (ii) a description of clinical competencies important for effective intervention delivery; (iii) a summary of relevant evidence in three key cohorts: acquired brain injury, psychiatric disorders, and older adults, focusing on interventions with sound evidence for improving activity and participation outcomes; (iv) an overview of considerations for sustainable implementation of neuropsychological interventions as 'core business'; and finally, (v) a call to action.

Development and Impact of a Cognitive Reserve Enhancement Program for Climacteric Korean Women

BACKGROUND

In light of the rising incidence of mild cognitive impairment in women, an appropriate cognitive reserve enhancement program is urgently needed for women experiencing climacteric symptoms.

PURPOSE

The purpose of this study was to develop a cognitive reserve enhancement program for climacteric women based on cognitive reserve theory (CRT) and to verify its effectiveness.

METHODS

A nonequivalence control group, pre- and post-quasi-experimental design was used. The 58 climacteric women with subjective memory deterioration enrolled as participants were divided into the experimental group (28 women), which received a 24-session CRT-based cognitive reserve enhance program, and the control group (30 women), the members of which received the cognitive training via a mobile application after completion of the study. Valid data from 24 experimental and 26 control participants were available for analysis. Objective cognitive functions, including overall cognitive, memory, attention, and language, were measured pretest and posttest using the following tools: Everyday Cognition Scale (subjective cognitive function), Center for Epidemiologic Studies Depression Scale (depression), and World Health Organization Quality of Life-Brief Version (quality of life).

RESULTS

The experimental group showed a statistically significant increase in overall cognitive function (t = 3.82, p = .001), memory (t = 2.63, p = .012), attention: number of correct answers (t = 2.12, p = .040), language high-frequency response speed (Z = -2.49, p = .013), and language low-frequency response speed (Z = -2.77, p = .006) in objective cognitive function after 8 weeks in comparison to the control group.

CONCLUSIONS/IMPLICATIONS FOR PRACTICE

The intervention program tested in this study to enhance cognitive reserve in climacteric women includes cognitive training, emotional and social support, and group physical activity components was found to be effective in enhancing cognitive function.

Correlation Between Lifestyle Patterns and Cognitive Function Among Community-Dwelling Older Chinese Adults in the Pre-Dementia Stages: A Latent Class Analysis

Lifestyle activity engagement is a modifiable factor for cognitive decline. We aimed to identify lifestyle patterns (LPs) among community-dwelling older adults in the pre-dementia stages and to explore the links between LPs, cognitive function, and individual characteristics. 702 older Chinese adults were recruited. Three LPs were identified by latent class analysis: active aging lifestyle pattern (AALP), leisure lifestyle pattern (LLP), and work-centered lifestyle pattern (WLP). AALP refers to participation in various activities that are meaningful to individuals and benefit their well-being. LLP is the pattern of activities aimed at recreation. WLP refers to the LP where individuals are most likely to engage in work-related activities. However, only AALP is protected against mild cognitive impairment (MCI). Multinomial logistic regression models revealed the differences in individual characteristics among participants with different LPs, indicating the importance of tailored intervention strategies. As a protective factor against MCI, AALP should be highlighted in community-based care.

Subjective Cognitive Complaints and Anecdotal Descriptions of Postoperative Cognitive Decline: Missing Pieces of the Postoperative Neurocognitive Disorder Puzzle

Postoperative cognitive recovery is deeply important to patients and perioperative clinicians. Despite decades of data on "postoperative cognitive decline" (POCD), a research diagnosis based on objective cognitive test performance, perspectives on subjective cognitive complaints (SCC) after modern surgery/anesthesia have not been systematically collected or studied despite their recent inclusion in the 2018 redefinition of "postoperative neurocognitive disorder." The authors describe the alignment between SCC anecdotes and the research diagnosis of POCD, contextualizing these findings using recent literature within and outside anesthesiology. This article prepares anesthesiologists to discuss what is, and is not, known about subjective cognitive recovery after surgery/anesthesia.

Structural disruption in subjective cognitive decline and mild cognitive impairment

Subjective cognitive decline (SCD) marks the initial stage in Alzheimer's disease continuum. Nonetheless, current research findings regarding brain structural changes in the SCD are inconsistent. In this study, 37 SCD patients, 28 mild cognitive impairment (MCI) patients, and 42 healthy controls (HC) were recruited to investigate structural alterations. Morphological and microstructural differences among the three groups were analyzed based on T1- and diffusion-weighted images, correlating them with neuropsychological assessments. Additionally, classification analysis was performed by using support vector machines (SVM) categorize participants into three groups based on MRI features. Both SCD and MCI showed decreased volume in left inferior parietal lobe (IPL) compared to HC, while SCD showed altered morphologies in the right inferior temporal gyrus (ITG), right insula and right amygdala, and microstructures in fiber tracts of the right ITG, lateral occipital cortex (LOC) and insula relative to MCI. Moreover, the volume in the left IPL, right LOC, right amygdala and diffusivity value in fiber tracts of right LOC were significantly correlated with cognitive functions across all subjects. The classification models achieved an accuracy of > 0.7 (AUC = 0.8) in distinguishing the three groups. Our findings suggest that SCD and MCI share similar atrophy in the IPL but show more differences in morphological and microstructural features of cortical-subcortical areas.

Olfactory Identification as a Biomarker for Cognitive Impairment: Insights from Healthy Aging, Subjective Cognitive Decline, and Mild Cognitive Impairment

Introduction: This study aims to investigate the relationship between olfactory identification (OI) and cognitive impairment by examining OI abilities across various stages of cognitive deterioration. Methods: A total of 264 participants were divided into three groups based on cognitive status: cognitively healthy, subjective cognitive, and mild cognitive impairment. All participants were assessed using the Sniffin' Sticks Olfactory Identification test and a comprehensive neuropsychological test battery. Results: Our results highlight the main effects of age and cognitive status on OI scores. Regarding cognitive abilities, OI is associated with measures of short-term memory, long-term, working memory, and selective attention. Finally, logistic regression models showed that OI is a significant predictor for discriminating SCD from CH, MCI from CH, and MCI from SCD. Discussion: These findings suggest the addition of olfactory identification measures in neuropsychological assessments could improve the early detection of individuals at risk for cognitive impairment.

Views of Aging and Subjective Cognition in Middle-Aged and Older Adults: A Systematic Review

INTRODUCTION

Views of aging have been linked with many important outcomes in older adults. Subjective cognition, or one's perception of their cognitive functioning, may be a valuable indicator of cognitive changes as individuals age, but is known to be impacted by a variety of factors. The aim of this systematic review was to synthesize the evidence on relationships between views of aging and subjective cognition, including whether and how these relationships may differ based on age.

METHODS

Guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria, we conducted a comprehensive literature search in four databases: PubMed, CINAHL, PsycINFO, and ProQuest Dissertations and Theses. Critical appraisal utilized the Critical Appraisal Skills Programme (CASP) checklists. Twenty sources (including 21 studies) met inclusion and exclusion criteria, from which data were systematically extracted and results narratively synthesized.

RESULTS

Seventeen out of the 21 identified studies (81%) found a relationship between more positive views of aging and better subjective cognition; however, some studies reported mixed results based on the domain of aging views. Domains that were consistently associated with subjective cognition were subjective age, attitudes toward one's own aging, aging well, and essentialist beliefs about aging. Only three studies reported age group differences or changes in associations over time, precluding conclusions about differences across middle- and older ages.

CONCLUSION

Most studies supported associations between views of aging and subjective cognition. More longitudinal as well as qualitative research is needed to advance understanding of factors that influence these relationships.

Longitudinal Patterns and Predictors of Cognitive Impairment Classification Stability

OBJECTIVE

Classifications such as Cognitive Impairment, No Dementia (CIND) are thought to represent the transitory, pre-clinical phase of dementia. However, increasing research demonstrates that CIND represents a nonlinear, unstable entity that does not always lead to imminent dementia. The present study utilizes a longitudinal repeated measures design to gain a thorough understanding of CIND classification stability patterns and identify predictors of future stability. The objectives were to i) explore patterns of longitudinal stability in cognitive status across multiple assessments and ii) investigate whether select baseline variables could predict 6-year CIND stability patterns.

METHOD

Participants (N = 259) included older adults (aged 65-90 years) from Project MIND, a six-year longitudinal repeated measures design in which participants were classified as either normal cognition (NC) or CIND at each annual assessment. A latent transition analysis approach was adapted in order to identify and characterize transitions in CIND status across annual assessments. Participants were classified as either Stable NC, Stable CIND, Progressers, Reverters, or Fluctuaters. Multinomial logistic regression was employed to test whether baseline predictors were associated with cognitive status stability patterns.

RESULTS

The sample demonstrated high rates of reversion and fluctuation in CIND status across annual assessments. Additionally, premorbid IQ and CIND severity (i.e., single vs. multi-domain impairment) at baseline were significantly associated with select stability outcomes.

CONCLUSIONS

CIND status was unstable for several years following baseline assessment and cognitive reserve may delay or protect against demonstrable cognitive impairment. Further, consideration of cognitive impairment severity at the time of initial classification may improve CIND classifications.

Risk of Stroke or Heart Attack in Mild Cognitive Impairment and Subjective Cognitive Impairment

BACKGROUND

The study aimed to identify Mild Cognitive Impairment (MCI) as an alert clinical manifestation of increased probability of major acute vascular events (MVEs), such as Ischemic Stroke and heart attack.

METHODS

In a longitudinal study, 181 (M = 81, F = 100; mean age of 75.8 ± 8.69 years) patients were enrolled and divided into three groups based on diagnosis: Subjective Cognitive Impairment (SCI), amnestic MCI Single Domain (aMCI-SD), and amnestic MCI More Domain (aMCI-MD). Clinical assessment and the presence of vascular risk factors were collected.

RESULTS

The distribution of MVEs showed a higher incidence in the first two years of follow-up of 7.4% in SCI, 12.17% in aMCI-SD, and 8.57% in aMCI-MD. Acute Myocardial Infarction showed a major incidence in one year of follow-up (41%) and in two years of follow-up (29%). Also, Ischemic Stroke showed a major incidence in one year of follow-up (30%) and in two years of follow-up (40%). A statistically significant difference in the progression to dementia was shown (SCI 3.75%; aMCI-SD 10.43%; aMCI-MD 37%; p-value < 0.001).

CONCLUSIONS

MCI is considered an expression of the systemic activation of mechanisms of endothelial damage, representing a diagnosis predictive of increased risk of MVEs.

The Contribution of the Face-Name Associative Recognition Test to Objectifying the Impairment of Associative Memory in Subjective Cognitive Decline

OBJECTIVE

Subjective cognitive decline (SCD) is defined as a self-reported perception of cognitive decline that occurs without clear objective signs of cognitive impairment. There is still uncertainty in the literature about the reliability of SCD as an accurate indicator of the early stages of major neurocognitive disorders. Furthermore, objectifying cognitive impairment in SCD is difficult, mainly due to the insensitivity of the assessment instruments. The main objective of this study was to investigate the potential contribution of the face-name associative recognition test (FNART) to the objective identification of memory impairment in SCD.

METHOD

A research sample of 69 adults with SCD and 69 healthy controls (HCs) recruited in the community were administered in the FNART, which included 32 photographs of neutral faces associated with 32 first names.

RESULTS

The total score of the HC group in the FNART was significantly better than that of the SCD group. Moreover, analyses based on the serial position of the stimuli showed that the SCD group performed significantly worse than the HC group only for the middle items (stimuli placed at the beginning or end of learning lists are more likely to be recalled than those presented in the middle), while no primacy and recency effects were found in the HCs.

CONCLUSIONS

These findings indicate that associative episodic memory is more vulnerable in individuals with subjective cognitive decline (SCD) compared to those without cognitive complaints. Additionally, they suggest that the FNART may be effective in identifying cognitive decline in the preclinical stage of Alzheimer's disease.

Behavioural and neuronal substrates of serious game-based computerised cognitive training in cognitive decline: randomised controlled trial

BACKGROUND

Investigations of computerised cognitive training (CCT) show heterogeneous results in slowing age-related cognitive decline.

AIMS

To comprehensively evaluate the effectiveness of serious games-based CCT, integrating control conditions, neurophysiological and blood-based biomarkers, and subjective measures.

METHOD

In this bi-centric randomised controlled trial with parallel groups, 160 participants (mean age 71.3 years) with cognitive impairment ranging from subjective decline to mild cognitive impairment, were pseudo-randomised to three arms: an intervention group receiving CCT immediately, an active control (watching documentaries) and a waitlist condition, which both started the CCT intervention after the control period. Both active arms entailed a 3-month intervention period comprising a total of 60 at-home sessions (five per week) and weekly on-site group meetings. In the intervention group, this was followed by additional 6 months of CCT, with monthly booster sessions to assess long-term training effects. Behavioural and subjective changes were assessed in 3-month intervals. Biological effects were measured by amyloid blood markers and magnetic resonance imaging obtained before and after training.

RESULTS

Adherence to the training protocol was consistently high across groups and time points (4.87 sessions per week). Domain-specific cognitive scores showed no significant interaction between groups and time points. Significant cognitive and subjective improvements were observed after long-term training. Voxel-based morphometry revealed no significant changes in grey matter volume following CCT, nor did amyloid levels moderate its effectiveness.

CONCLUSIONS

Our study demonstrates no benefits of 3 months of CCT on cognitive or biological outcomes. However, positive effects were observed subjectively and after long-term CCT, warranting the inclusion of CCT in multicomponent interventions.

Long COVID and recovery from Long COVID: quality of life impairments and subjective cognitive decline at a median of 2 years after initial infection

BACKGROUND

Recovery from SARS CoV-2 infection is expected within 3 months. Long COVID occurs after SARS-CoV-2 when symptoms are present for more than 3 months that are continuous, relapsing and remitting, or progressive. Better understanding of Long COVID illness trajectories could strengthen patient care and support.

METHODS

We characterized functional impairments, quality of life (QoL), and cognition among patients who recovered from SARS-CoV-2 infection within 3 months (without Long COVID), after 3 months (Recovered Long COVID), or remained symptomatic (Long COVID). Among 7305 patients identified with previous SARS-CoV-2 infection between March 2020 and December 2021, confirmed in the medical record with laboratory test or physician diagnosis, 435 (6%) completed a single self-administered survey between March 2022 and September 2022. Multi-domain QoL and cognitive concerns were evaluated using PROMIS-29 and the Cognitive Change Index-12.

RESULTS

Nearly half the participants (47.7%) were surveyed more than 2 years from initial infection (median = 23.3 months; IQR = 18.6, 26.7) and 86.7% were surveyed more than 1 year from infection. A significantly greater proportion of the Long COVID (n = 215) group, (Current and Recovered combined), had moderate-to-severe impairment in all health domains assessed compared to those Without Long COVID (n = 220; all p < 0.05). The Recovered Long COVID group (n = 34) had significantly lower prevalence of fatigue, pain, depression, and physical and social function impairment compared to those with Current Long COVID (n = 181; all p < 0.05). However, compared to patients Without Long COVID, the Recovered Long COVID group had greater prevalences of fatigue, pain (p ≤ 0.06) and subjective cognitive decline (61.8% vs 29.1%; p < 0.01). Multivariate relative risk (RR) regression indicated Long COVID risk was greater for older age groups (RR range 1.46-1.52; all p ≤ 0.05), those without a bachelor's degree (RR = 1.33; 95% CI = 1.03-1.71; p = 0.03), and those with 3 or more comorbidities prior to SARS-CoV-2 infection (RR = 1.45; 95% CI = 1.11-1.90; p < 0.01).

CONCLUSIONS

Long COVID is associated with long-term subjective cognitive decline and diminished quality of life. Clinically significant cognitive complaints, fatigue, and pain were present even in those who reported they had recovered from Long COVID. These findings have implications for the sustainability of participation in work, education, and social activities.

Predicting brain atrophy and cognitive aging trajectories with baseline subjective cognitive concerns in cognitively normal older adults

Subjective cognitive concerns (SCC) are common even in cognitively normal older adults who lack objectively-detectable deficits on standard neuropsychological evaluation. The clinical relevance of these concerns, particularly considering the nature of concerns (e.g., memory versus non-memory), remains unclear. Thus, we examined whether baseline memory and non-memory SCC relate to longitudinal change in brain volume and neuropsychological test performance in 476 functionally-intact, objectively unimpaired older adults (Mage = 72y, 56 % female, follow-up time = 1 - 9 years). Mixed-effects models revealed that both higher baseline memory and non-memory SCC predicted greater atrophy in total gray matter and dorsolateral prefrontal cortex atrophy over time, while only memory SCC predicted steeper medial temporal lobe atrophy. Regarding neuropsychological performance, higher non-memory SCC predicted decline in processing speed performance, while memory SCC did not predict neuropsychological trajectories. SCC are a risk factor for more adverse brain and cognitive aging trajectories, even in functionally-intact, seemingly cognitively normal older adults.

Association Between Dietary Diversity and Subjective Cognitive Decline in the Middle-Aged and Elderly Chinese Population: A Cross-Sectional Study

BACKGROUND

This cross-sectional study aimed to examine the association between dietary diversity and risk of subjective cognitive decline (SCD), a precursor of dementia, in middle-aged and elderly Chinese populations residing in eastern China.

METHODS

Participants aged ≥ 45 years were recruited from a community in an eastern Chinese city after excluding potential objective cognitive impairment using the Mini-Cognitive Assessment Instrument (Mini-Cog). SCD was assessed using the Subjective Cognitive Decline Questionnaire-9 (SCD-Q9). Dietary data were collected using the Dietary Quality Questionnaire (DQQ), and the Food Group Diversity Score (FGDS) and the Consumed All Five Recommended Food Score (All-5) were calculated as indicators of dietary diversity. Odds ratios (ORs) and 95% confidence intervals (CIs) were computed to evaluate the associations of FGDS and All-5 scores with SCD after adjusting for age, sex, socioeconomic status, lifestyle factors, and health status.

RESULTS

Among the 871 participants, 358 (41.1%) were classified as having SCD. Compared with participants with the highest FGDS (≥8) and those with the highest All-5 score (5), those with the lowest FGDS (≤4) and the lowest All-5 score (≤3) exhibited 85% (OR = 1.85; 95% CI: 1.10-3.13; p = 0.02) and 90% (OR = 1.90; 95% CI: 1.21-2.97; p < 0.01) higher risk of SCD, respectively, after adjusting for all covariates. Fruits were the only food group among the All-5 components that demonstrated a significant association with SCD risk.

CONCLUSIONS

Poor dietary diversity was associated with an elevated risk of SCD in middle-aged and older adults, and fruits were the food group with the most substantial effect.

Ten-words recall test: an effective tool to differentiate mild cognitive impairment from subjective cognitive decline

Introduction

Subjective cognitive decline (SCD) and mild cognitive impairment (MCI) are stages 2 and 3, respectively, of the Alzheimer's continuum. The Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-cog's) ten-words recall test is a validated method for the early detection of cognitive impairment in Alzheimer's disease. However, limited studies have investigated its ability to differentiate between SCD and MCI.

Methods

203 participants with SCD and 62 participants with MCI underwent multiple neuropsychological assessments. The Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment-Basic (MOCA-B) served as brief global cognition tests. A binary logistic regression model was used to analyze the potential factors affecting MCI. The accuracy of the ten-words recall test was assessed using the area under the receiver operating characteristic (ROC) and the area under the curve (AUC).

Results

The neuropsychological assessment revealed significant differences in the ten-words recall test scores between the SCD (median age 61 years; 70.44% female) and MCI (median age 64 years; 61.29% female) groups (p < 0.001), with the MCI group scoring the highest. Using a cut-off value of 3.15 for the ten-words recall test, sensitivity for distinguishing MCI from SCD reached 87%, while specificity stood at 61% (AUC 0.777, p < 0.001). DeLong's test indicated no statistically significant difference in the ten-words recall test's ability to distinguish between SCD and MCI compared to the total score of ADAS-Cog (AUC 0.833, p) and MMSE (AUC 0.784, p > 0.05). However, a significant difference was observed when compared to MoCA-B (AUC 0.973, p < 0.001). In the population with an education level of ≤ 9 years, the optimal cut-off value for the ten-words recall test was 3.15, yielding a sensitivity of 91% and a specificity of 45% (AUC = 0.674, p = 0.030). In the population with an education level > 9 years, the optimal cut-off value was 3.63, resulting in a sensitivity of 79% and a specificity of 71% (AUC = 0.785, p < 0.001).

Discussion

The ten-words recall test from the ADAS-cog may detect MCI early owing to its simplicity and quick administration. It is an effective and convenient tool for rapidly identifying mild cognitive impairment.

Examination of Congruity between Subjective and Objective Working Memory in Veterans with Mild TBI and Relation to Psychiatric Symptoms and Childhood Trauma

OBJECTIVES

There is conflicting evidence regarding congruence between subjective cognitive decline and objective cognitive performance for individuals with a history of mild traumatic brain injury (mTBI). The current study investigated the congruity between subjective and objective cognition, particularly working memory, among veterans with an mTBI history, accounting for post-traumatic stress disorder (PTSD) and childhood trauma.

METHODS

Participants included 35 veterans with a history of mTBI sustained during deployment. Participants completed measures of subjective [i.e., Behavioral Inventory Rating of Executive Functioning (BRIEF)] and objective working memory (i.e., WAIS-IV working memory index). Congruity between subjective and objective working memory was examined using linear regression. Bonferroni-corrected correlations were run to explore relationships among working memory, psychiatric symptoms, mTBI severity, and childhood trauma.

RESULTS

Among Veterans with mTBI, subjective working memory and objective working memory performance were not significantly related (p > 0.05); however, the overall model was significant (p < 0.0001), and childhood trauma was a notable predictor (p = 0.02). Greater PTSD, depression, and sleep symptoms were significantly related to increased subjective working memory concerns, even after Bonferroni adjustments (ps < 0.0001). Better objective working memory was significantly related to a fewer number of childhood traumatic events; however, this did not sustain corrections. The majority of individuals (67%) endorsed significant working memory complaints, despite objectively performing within normal limits (within 1 SD and above).

CONCLUSIONS

Subjective-objective working memory congruity among veterans with mTBI was limited. Subjective, but not objective, working memory concerns were associated with greater PTSD, depression, and sleep symptoms. Childhood trauma was a notable factor that contributed to both subjective and objective cognitive concerns. There remains clinical value in assessing subjective cognitive concerns given the strong relationships with psychiatric problems and, hence, a focus for intervention.

Prevalence and risk factors of subjective cognitive decline in older adults in Baotou, China: a cross-sectional study

Objectives

Subjective cognitive decline (SCD) as a stage between healthy cognition and early neurocognitive disorders, has been proposed to be helpful in the diagnosis of prodromal neurocognitive disorders. To investigate the prevalence of SCD and the related risk factors on the prevalence.

Methods

A cross-sectional study involving 1,120 elderly subjects residing in Baotou, China. From June 2021 to June 2023, the data were gathered by research assistants with training utilizing standardized questionnaires. The following factors were evaluated: subjective cognitive decline, physical and cognitive activity levels, past medical history, demographics, instrumental activities of daily living, and cognitive function. Risk factors of SCD were used chi-square tests and multivariate logistic regression analysis.

Results

The prevalence of SCD was 43.8%. Permanent residence, marital status, BMI, dietary habits, average sleep duration per night, smoking, diabetes, coronary heart disease, and visual impairment were significantly associated with SCD (p < 0 0.05). Multivariable logistic regression analysis showed obesity, vegetarian-based, smoking for a long time, diabetes and coronary heart disease, visual impairment, no spouse, and average sleep duration per night <6 h were independent risk factors for SCD. Based on the gender analysis, the difference in marital status, dietary habits, average sleep duration per night, smoking, drinking, and hypertension was statistically significant (p < 0.001).

Conclusion

The prevalence of subjective cognitive decline was high among elder adults. We discovered significant differences in the prevalence or risk factors for SCD between men and women based on their sex. This study provides a more theoretical basis for the early prevention and screening of cognitive impairment diseases in the elderly population.

Subjective Cognitive Decline Plus and Longitudinal Assessment and Risk for Cognitive Impairment

Importance

Subjective cognitive decline (SCD) is recognized to be in the Alzheimer disease (AD) cognitive continuum. The SCD Initiative International Working Group recently proposed SCD-plus (SCD+) features that increase risk for future objective cognitive decline but that have not been assessed in a large community-based setting.

Objective

To assess SCD risk for mild cognitive impairment (MCI), AD, and all-cause dementia, using SCD+ criteria among cognitively normal adults.

Design, Setting, and Participants

The Framingham Heart Study, a community-based prospective cohort study, assessed SCD between 2005 and 2019, with up to 12 years of follow-up. Participants 60 years and older with normal cognition at analytic baseline were included. Cox proportional hazards (CPH) models were adjusted for baseline age, sex, education, APOE ε4 status, and tertiles of AD polygenic risk score (PRS), excluding the APOE region. Data were analyzed from May 2021 to November 2023.

Exposure

SCD was assessed longitudinally using a single question and considered present if endorsed at the last cognitively normal visit. It was treated as a time-varying variable, beginning at the first of consecutive, cognitively normal visits, including the last, at which it was endorsed.

Main Outcomes and Measures

Consensus-diagnosed MCI, AD, and all-cause dementia.

Results

This study included 3585 participants (mean [SD] baseline age, 68.0 [7.7] years; 1975 female [55.1%]). A total of 1596 participants (44.5%) had SCD, and 770 (21.5%) were carriers of APOE ε4. APOE ε4 and tertiles of AD PRS status did not significantly differ between the SCD and non-SCD groups. MCI, AD, and all-cause dementia were diagnosed in 236 participants (6.6%), 73 participants (2.0%), and 89 participants (2.5%), respectively, during follow-up. On average, SCD preceded MCI by 4.4 years, AD by 6.8 years, and all-cause dementia by 6.9 years. SCD was significantly associated with survival time to MCI (hazard ratio [HR], 1.57; 95% CI, 1.22-2.03; P <.001), AD (HR, 2.98; 95% CI, 1.89-4.70; P <.001), and all-cause dementia (HR, 2.14; 95% CI, 1.44-3.18; P <.001). After adjustment for APOE and AD PRS, the hazards of SCD were largely unchanged.

Conclusions and Relevance

Results of this cohort study suggest that in a community setting, SCD reflecting SCD+ features was associated with an increased risk of future MCI, AD, and all-cause dementia with similar hazards estimated in clinic-based settings. SCD may be an independent risk factor for AD and other dementias beyond the risk incurred by APOE ε4 and AD PRS.

The mutual longitudinal mediating effects of psychological and physical disorders on cognitive impairment among older adults

BACKGROUND

The potential mutual effect of physical and psychological disorders on cognitive function is critical for preventing cognitive impairment among older adults. We aimed to investigate the mediating role of physical and psychological disorders in their associations with cognitive function.

METHODS

We conducted a prospective cohort study using the Health and Retirement Study, involving 5308 adults aged 60 years or older. Physical disorders included seven self-reported physician-diagnosed conditions. Psychological disorder and cognitive function were ascertained using the 8-item Centers for Epidemiologic Research Depression scale and the 27-point HRS cognitive scale, respectively. Multivariable linear regression models were used to assess the association of the baseline scores of physical and psychological disorders with subsequent cognitive scores. Second-order cross-lagged panel models (CLPM) were used to assess the longitudinal mediating roles, respectively.

RESULTS

The higher psychological disorder scores (β = -0.15; P < 0.0001) and physical disorders scores (β = -0.18; P < 0.0001) were, the worse the cognitive function was. CLPM revealed a significant longitudinal mediating effect of baseline physical disorders through changes in psychological disorder from 2002 to 2010 on the cognitive scores changes from 2002 to 2010 (β = -0.02; P < 0.0001). Meanwhile, the longitudinal mediating effect of baseline psychological disorder scores through physical disorders changes from 2002 to 2010 on the cognitive scores changes from 2002 to 2010 was significant (β = -0.004; P = 0.005).

CONCLUSIONS

The mutual longitudinal mediating effects of psychological disorder and physical disorder indicate that among older adults, physical and psychological disorders accelerate cognitive impairment as a whole and mutually reinforcing process.

Musical Activity Engagement, Depressive Symptoms, Physical Activity, and Cognitive Function in People With Type 2 Diabetes

BACKGROUND

Music interventions have beneficial effects on cognitive function and related risk factors, such as depressive symptoms and behavior of exercise participation. However, little research has been conducted on music's effects on people with type 2 diabetes, and evidence of the effect remains inconclusive in this population.

OBJECTIVES

Guided by the theory of music, mood, and movement (MMM), this exploratory study aimed to examine the direct and indirect effects of musical activity engagement, depressive symptoms, and physical activity on cognitive function in people with type 2 diabetes.

METHODS

The present study is a secondary data analysis using the cross-sectional data collected from the Memory, Attention, and Problem-Solving Skills for Persons With Diabetes trial conducted between 2021 and 2023. Data were collected using self-reported questionnaires and a computerized cognitive assessment tool. A total of 189 people with type 2 diabetes and subjective cognitive decline were included in the study. Path analysis was conducted using IBM SPSS AMOS to examine the pathways of the proposed conceptual framework.

RESULTS

The study results partially support the MMM model for subjective cognitive function but not objective cognitive function. The path model demonstrated the significant direct effects of musical activity engagement on physical activity, physical activity on subjective cognitive function, and depressive symptoms on physical activity as well as on subjective cognitive function. There was a significant indirect effect of musical activity engagement on subjective cognitive function through physical activity-which fully mediated this relationship. However, no significant direct effect of musical activity engagement on depressive symptoms and subjective cognitive function was found.

DISCUSSION

The findings suggest that regular assessment of the presence of depressive symptoms and physical activity participation should be done in people with type 2 diabetes to identify potential modifiable factors and develop targeted interventions for cognitive health promotion. Also, our findings provide insights into the potential use of music to facilitate physical activity and manage cognitive health in people with type 2 diabetes. This study partially supports the MMM model; however, more research with a rigorous study design and larger sample size is needed to better understand the relationships among musical activity engagement, depressive symptoms, physical activity, and cognitive function.

Effect of matcha green tea on cognitive functions and sleep quality in older adults with cognitive decline: A randomized controlled study over 12 months

OBJECTIVE

Lifestyle habits after middle age significantly impact the maintenance of cognitive function in older adults. Nutritional intake is closely related to lifestyle habits; therefore, nutrition is a pivotal factor in the prevention of dementia in the preclinical stages. Matcha green tea powder (matcha), which contains epigallocatechin gallate, theanine, and caffeine, has beneficial effects on cognitive function and mood. We conducted a randomized, double-blind, placebo-controlled clinical study over 12 months to examine the effect of matcha on cognitive function and sleep quality.

METHODS

Ninety-nine participants, including 64 with subjective cognitive decline and 35 with mild cognitive impairment were randomized, with 49 receiving 2 g of matcha and 50 receiving a placebo daily. Participants were stratified based on two factors: age at baseline and APOE genotype. Changes in cognitive function and sleep quality were analyzed using a mixed-effects model.

RESULTS

Matcha consumption led to significant improvements in social acuity score (difference; -1.39, 95% confidence interval; -2.78, 0.002) (P = 0.028) as evaluated by the perception of facial emotions in cognitive function. The primary outcomes, that is, Montreal Cognitive Assessment and Alzheimer's Disease Cooperative Study Activity of Daily Living scores, showed no significant changes with matcha intervention. Meanwhile, Pittsburgh Sleep Quality Index scores indicated a trend toward improvement with a difference of 0.86 (95% confidence interval; -0.002, 1.71) (P = 0.088) between the groups in changes from baseline to 12 months.

CONCLUSIONS

The present study suggests regular consumption of matcha could improve emotional perception and sleep quality in older adults with mild cognitive decline. Given the widespread availability and cultural acceptance of matcha green tea, incorporating it into the daily routine may offer a simple yet effective strategy for cognitive enhancement and dementia prevention.

Comparison of subjective cognitive decline and polygenic risk score in the prediction of all-cause dementia, Alzheimer's disease and vascular dementia

BACKGROUND

Polygenic risk scores (PRS) and subjective cognitive decline (SCD) are associated with the risk of developing dementia. It remains to examine whether they can improve the established cardiovascular risk factors aging and dementia (CAIDE) model and how their predictive abilities compare.

METHODS

The CAIDE model was applied to a sub-sample of a large, population-based cohort study (n = 5,360; aged 50-75) and evaluated for the outcomes of all-cause dementia, Alzheimer's disease (AD) and vascular dementia (VD) by calculating Akaike's information criterion (AIC) and the area under the curve (AUC). The improvement of the CAIDE model by PRS and SCD was further examined using the net reclassification improvement (NRI) method and integrated discrimination improvement (IDI).

RESULTS

During 17 years of follow-up, 410 participants were diagnosed with dementia, including 139 AD and 152 VD diagnoses. Overall, the CAIDE model showed high discriminative ability for all outcomes, reaching AUCs of 0.785, 0.793, and 0.789 for all-cause dementia, AD, and VD, respectively. Adding information on SCD significantly increased NRI for all-cause dementia (4.4%, p = 0.04) and VD (7.7%, p = 0.01). In contrast, prediction models for AD further improved when PRS was added to the model (NRI, 8.4%, p = 0.03). When APOE ε4 carrier status was included (CAIDE Model 2), AUCs increased, but PRS and SCD did not further improve the prediction.

CONCLUSIONS

Unlike PRS, information on SCD can be assessed more efficiently, and thus, the model including SCD can be more easily transferred to the clinical setting. Nevertheless, the two variables seem negligible if APOE ε4 carrier status is available.

Altered functional connectivity of primary olfactory cortex-hippocampus-frontal cortex in subjective cognitive decline during odor stimulation

Subjective cognitive decline (SCD) is a high-risk population in the preclinical stage of Alzheimer's disease (AD), and olfactory dysfunction is a risk factor for dementia progression. The present study aimed to explore the patterns of functional connectivity (FC) changes in the olfactory neural circuits during olfactory stimulation in SCD subjects. A total of 56 SCD subjects and 56 normal controls (NCs) were included. All subjects were assessed with a cognitive scale, an olfactory behavior test, and olfactory task-based functional magnetic resonance imaging scanning. The FC differences in olfactory neural circuits between the two groups were analyzed by the generalized psychophysiological interaction. Additionally, we calculated and compared the activation of brain regions within the olfactory neural circuits during odor stimulation, the volumetric differences in brain regions showing FC differences between groups, and the correlations between neuroimaging indicators and olfactory behavioral and cognitive scale scores. During odor stimulation, the FC between the bilateral primary olfactory cortex (bPOC) and the right hippocampus in the SCD group was significantly reduced; while the FC between the right hippocampus and the right frontal cortex was significantly increased in the SCD group. The bPOC of all subjects showed significant activation, but no significant difference in activation between groups was found. No significant differences were observed in the volume of the brain regions within the olfactory neural circuits or in olfactory behavior between groups. The volume of the bPOC and right frontal cortex was significantly positively correlated with olfactory identification, and the volume of the right frontal cortex and right hippocampus was significantly correlated with cognitive functions. Furthermore, a significant correlation between the activation of bPOC and the olfactory threshold was found in the whole cohort. These results suggested that while the structure of the olfactory neural circuits and olfactory behavior in SCD subjects remained stable, there were significant changes observed in the FC of the olfactory neural circuits (specifically, the POC-hippocampus-frontal cortex neural circuits) during odor stimulation. These findings highlight the potential of FC alterations as sensitive imaging markers for identifying high-risk individuals in the early stage of AD.

Impact of repetitive negative thinking on subjective cognitive decline: insights into cognition and brain structure

Introduction

Individuals with subjective cognitive decline (SCD) express concern about self-perceived cognitive decline despite no objective impairment and are at higher risk of developing Alzheimer's disease. Despite documented links between SCD and repetitive negative thinking (RNT), the specific impact of RNT on brain integrity and cognition in exacerbating the SCD condition remains unclear. We aimed to investigate the influence of RNT on global cognition and brain integrity, and their interrelationships among healthy middle-aged and older adults experiencing SCD.

Methods

Out of 616 individuals with neuroimaging and neuropsychological data available, 89 (mean age = 56.18 years; 68.54% females) met SCD criteria. Eighty-nine non-SCD individuals matched by age, sex, and education were also selected and represented the control group (mean age = 56.09 years; 68.54% females). Global cognition was measured using the preclinical Alzheimer's cognitive composite (PACC5), which includes dementia screening, episodic memory, processing speed, and category fluency tests. RNT was calculated through three questionnaires assessing intrusive thoughts, persistent worry, and rumination. We generated cortical thickness (CTh) maps and quantified the volume of white matter lesions (WML) in the whole brain, as grey and white matter integrity measures, respectively.

Results

SCD individuals exhibited higher RNT scores, and thinner right temporal cortex compared to controls. No differences were observed in PACC5 and WML burden between groups. Only the SCD group demonstrated positive associations in the CTh-PACC5, CTh-RNT, and WML-RNT relationships.

Discussion

In this cross-sectional study, RNT was exclusively associated with brain integrity in SCD. Even though our findings align with the broader importance of investigating treatable psychological factors in SCD, further research may reveal a modulatory effect of RNT on the relationship between cognition and brain integrity in SCD.

Correlates of Mild Behavioral Impairment in Older Adults: Protocol for a Scoping Review

BACKGROUND

Understanding mild behavioral impairment, a relatively recent notion in neuropsychological studies, provides significant insights into early behavioral indicators of cognitive decline and predicts the onset of dementia in older adults. Although the importance of understanding mild behavioral impairment is acknowledged, comprehensive reviews of its correlates with older adults are limited.

OBJECTIVE

This scoping review aims to identify the impact of mild behavioral impairment on health outcomes in older adults and the factors associated with mild behavioral impairment.

METHODS

The review will adhere to the Joanna Briggs Institute's methodological principles for scoping reviews. We will include studies focusing mainly on mild behavioral impairment in older adults, with the literature on this topic being limited to the period from 2003 to the present. Other clinical diagnoses, such as cognitive impairment, Parkinson disease, and multiple sclerosis, will not be included. We will use databases including PubMed (MEDLINE), CINAHL, Web of Science, Embase, PsycINFO, Cochrane, and Scopus for relevant articles published in English. Both gray literature and peer-reviewed articles will be considered during screening. Three independent reviewers will extract data using a predefined data extraction tool. Extracted data will be presented using tables, figures, and a narrative summary aligned with review questions, accompanied by an analysis of study characteristics and categorization of mild behavioral impairment correlates.

RESULTS

The results will be presented as a descriptive summary, structured according to the associated factors related to mild behavioral impairment, and the health outcomes. Additionally, the data on study characteristics will be presented in tabular format. An exploratory search was conducted in July 2023 to establish a comprehensive search strategy, and iterative refinements to the scoping review protocol and formalization of methods were completed. A follow-up search is planned for May 2024, with the aim of submitting the findings for publication in peer-reviewed journals.

CONCLUSIONS

To our knowledge, this would be the first study to map the literature on the health-related factors and outcomes of mild behavioral impairment. The findings will support the development of interventions to prevent the occurrence of mild behavioral impairment and mitigate the negative outcomes of mild behavioral impairment.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/60009.

"In the spectrum of people who are healthy": Views of individuals at risk of dementia on using neurotechnology for cognitive enhancement

Neurotechnological cognitive enhancement has become an area of intense scientific, policy, and ethical interest. However, while work has increasingly focused on ethical views of the general public, less studied are those with personal connections to cognitive impairment. Using a mixed-methods design, we surveyed attitudes regarding implantable neurotechnological cognitive enhancement in individuals who self-identified as having increased likelihood of developing dementia (n=25; 'Our Study'), compared to a nationally representative sample of Americans (n=4726; 'Pew Study'). Participants in Our Study were additionally shown four videos showcasing hypothetical neurotechnological devices designed to enhance different cognitive abilities and were interviewed for more in-depth responses. Both groups expressed comparable degrees of worry and acknowledgement of potential ethical ramifications (all ps>0.05). Compared to the Pew Study, participants in Our Study expressed slightly higher desire (p<0.01), as well as higher acknowledgment for potential impacts on productivity (p<0.05). Ultimately, participants in Our Study were more likely to deem the device morally acceptable (56%; compared to Pew Study, 25.2%; p=0.0001). Interviews conducted in Our Study allowed participants to supply additional nuance and reasoning to survey responses, such as giving examples for increased productivity, perceived downsides of memory enhancement, or concerns regarding potentially resulting inequality. This study builds upon and adds to the growing focus on potential ethical issues surrounding neurotechnological cognitive enhancement by centering stakeholder perspectives, highlighting the need for inclusive research and consideration of diverse perspectives and lived experiences to ensure inclusive dialogue that best informs ethical and policy discussions in this rapidly advancing field.

The criteria used to rule out mild cognitive impairment impact dementia incidence rates in subjective cognitive decline

BACKGROUND

The research criteria for subjective cognitive decline (SCD) exclude mild cognitive impairment (MCI), but do not stipulate the use of specific MCI criteria. This study compared different approaches to defining (i.e., excluding) MCI during the ascertainment of SCD, focusing on the impact on dementia incidence rates in SCD.

METHODS

This cohort study utilized routine healthcare data collected in the Essex Memory Clinic from 1999 to 2023. Two different operationalizations of the SCD criteria were used to categorize the cohort into two SCD patient samples. One sample was based on local clinical practice - MCI was excluded according to the Winblad criteria (this sample was termed SCDWinblad). The other sample was created via the retrospective application of the Jak/Bondi criteria for the exclusion of MCI (termed SCDJak/Bondi). Only patients aged ≥ 55 years at baseline with ≥ 12 months follow-up were considered for inclusion. The initial clinical/demographic characteristics of the samples were compared. Rates of incident dementia were calculated for each sample, and unadjusted and Mantel-Haenszel-adjusted incidence rate ratios were calculated to compare dementia incidence between the SCD samples.

RESULTS

The Essex Memory Clinic database included 2,233 patients in total. The SCD and study eligibility criteria were used to select SCDWinblad (n = 86) and SCDJak/Bondi (n = 185) samples from the database. Median follow-up (3 years) did not differ between the two samples. The SCDJak/Bondi sample was significantly older than the SCDWinblad at first assessment (median age: 74 versus 70 years) and had poorer scores on tests of global cognition, immediate and delayed verbal recall, and category fluency. Following adjustment for age, the dementia incidence rate ratio [95% confidence interval] was 3.7 [1.5 to 9.3], indicating a significantly greater rate of progression to dementia in SCDJak/Bondi.

CONCLUSIONS

This study highlights that the approach used to ascertain SCD has important implications for both SCD phenotypes and prognosis. This underscores the importance of how MCI is operationalized within SCD studies. More broadly, the findings add to a growing body of work indicating that objective cognition should not be overlooked in SCD, and offer a potential explanation for the heterogeneity across the SCD prognostic literature.

Gardening and subjective cognitive decline: a cross-sectional study and mediation analyses of 136,748 adults aged 45+ years

BACKGROUND

Given the benefits of gardening for physical and psychological health, we explored whether gardening was associated with lower risks of subjective cognitive decline (SCD), a precursor of dementia, and SCD-related functional limitations.

METHODS

Included in this cross-sectional study were 136,748 participants aged 45 + years old from the Behavioral Risk Factor Surveillance System 2019 survey, who were then categorized into three groups according to self-reported exercise status: non-exercisers, gardeners, and other exercisers. SCD was assessed via a questionnaire, and SCD-related functional limitations were referred to as having difficulties in engaging in household or social activities due to SCD. The odds ratio (OR) and 95% confidence interval (CI) were calculated to assess the associations of gardening with SCD and SCD-related functional limitations, adjusted for age, sex, socioeconomic status, lifestyle factors, and health status. Mediation analyses were conducted to examine whether the observed association between gardening and SCD was mediated by energy expenditure (MET-hours/week), depression status, and consumption of fruits and vegetables.

RESULTS

Overall, 11.1% and 5.4% of participants self-reported experiencing SCD and SCD-related functional limitations, respectively. The adjusted OR for gardeners vs. non-exercisers, was 0.72 (95% CI 0.62-0.83) for SCD and 0.57 (95% CI 0.44-0.73) for SCD-related functional limitations. The observed association between gardening and SCD was explained by higher energy expenditure (39.0%), lower likelihood of having depression (21.5%), and higher consumption of fruits and vegetables (3.4%) (P<0.05 for all). Similar patterns were observed for SCD-related functional limitations.

CONCLUSION

In this nationally representative sample, gardening was associated with better cognitive status, which may be mainly attributed to better depression status and energy expenditure.

Subjective Cognitive Decline in Community-Dwelling Older Adults With Objectively Normal Cognition: Mediation by Depression and Instrumental Activities of Daily Living

OBJECTIVE

Subjective cognitive decline (SCD) refers to self-reported memory loss despite normal cognitive function and is considered a preclinical stage of Alzheimer's disease. This study aimed to examine the mediating effects of depression and Instrumental Activities of Daily Living (IADL) on the association between the scoring of Clinical Dementia Rating Scale-Sum of Boxes (CDR-SB) and Subjective Cognitive Decline Questionnaire (SCD-Q).

METHODS

A sample of 139 community-dwelling older adults aged 65-79 with normal cognitive function completed the SCD-Q, a comprehensive neuropsychological battery, and functional/psychiatric scales. We conducted 1) a correlation analysis between SCD-Q scores and other variables and 2) a path analysis to examine the mediating effects of depression and IADL on the relationship between CDR-SB and SCD-Q.

RESULTS

CDR-SB was found to be indirectly associated with SCD-Q, with depressive symptoms mediating this relationship. However, no direct association was observed between SCD-Q and CDR-SB. Additionally, IADL was not associated with SCD-Q and did not mediate the relationship between CDR-SB and SCD-Q. The model fit was acceptable (minimum discrepancy function by degrees of freedom divided [CMIN/DF]=1.585, root mean square error of approximation [RMSEA]=0.065, comparative fit index [CFI]=0.955, Tucker-Lewis index [TLI]=0.939).

CONCLUSION

Our results suggest that SCD-Q is influenced by depressive symptoms, but not by IADL. The role of depressive symptoms as a mediator between CDR-SB and SCD-Q indicates that psychological factors may contribute to the perception of SCD. Therefore, interventions targeting depression may mitigate the concerns associated with SCD and reduce feelings of worse performance compared to others of the same age group.

Cerebral Amyloidosis in Individuals with Subjective Cognitive Decline: From Genetic Predisposition to Actual Cerebrospinal Fluid Measurements

The possible relationship between Subjective Cognitive Decline (SCD) and dementia needs further investigation. In the present study, we explored the association between specific biomarkers of Alzheimer's Disease (AD), amyloid-beta 42 (Aβ42) and Tau with the odds of SCD using data from two ongoing studies. In total, 849 cognitively normal (CN) individuals were included in our analyses. Among the participants, 107 had available results regarding cerebrospinal fluid (CSF) Aβ42 and Tau, while 742 had available genetic data to construct polygenic risk scores (PRSs) reflecting their genetic predisposition for CSF Aβ42 and plasma total Tau levels. The associations between AD biomarkers and SCD were tested using logistic regression models adjusted for possible confounders such as age, sex, education, depression, and baseline cognitive test scores. Abnormal values of CSF Aβ42 were related to 2.5-fold higher odds of SCD, while higher polygenic loading for Aβ42 was associated with 1.6-fold higher odds of SCD. CSF Tau, as well as polygenic loading for total Tau, were not associated with SCD. Thus, only cerebral amyloidosis appears to be related to SCD status, either in the form of polygenic risk or actual CSF measurements. The temporal sequence of amyloidosis being followed by tauopathy may partially explain our findings.

Diurnal cortisol, neuroinflammation, and neuroimaging visual rating scales in memory clinic patients

BACKGROUND

Neuroinflammation is a hallmark of the Alzheimer's disease (AD) pathogenic process. Cortisol dysregulation may increase AD risk and is related to brain atrophy. This cross-sectional study aims to examine interactions of cortisol patterns and neuroinflammation markers in their association with neuroimaging correlates.

METHOD

134 participants were recruited from the Karolinska University Hospital memory clinic (Stockholm, Sweden). Four visual rating scales were applied to magnetic resonance imaging or computed tomography scans: medial temporal lobe atrophy (MTA), global cortical atrophy (GCA), white matter lesions (WML), and posterior atrophy. Participants provided saliva samples for assessment of diurnal cortisol patterns, and underwent lumbar punctures for cerebrospinal fluid (CSF) sampling. Three cortisol measures were used: the cortisol awakening response, total daily output, and the ratio of awakening to bedtime levels. Nineteen CSF neuroinflammation markers were categorized into five composite scores: proinflammatory cytokines, other cytokines, angiogenesis markers, vascular injury markers, and glial activation markers. Ordinal logistic regressions were conducted to assess associations between cortisol patterns, neuroinflammation scores, and visual rating scales, and interactions between cortisol patterns and neuroinflammation scores in relation to visual rating scales.

RESULT

Higher levels of angiogenesis markers were associated with more severe WML. Some evidence was found for interactions between dysregulated diurnal cortisol patterns and greater neuroinflammation-related biomarkers in relation to more severe GCA and WML. No associations were found between cortisol patterns and visual rating scales.

CONCLUSION

This study suggests an interplay between diurnal cortisol patterns and neuroinflammation in relation to brain structure. While this cross-sectional study does not provide information on causality or temporality, these findings suggest that neuroinflammation may be involved in the relationship between HPA-axis functioning and AD.

Memory complaint in a middle-income country: a four-year longitudinal study in a cohort with low-education

BACKGROUND

 Memory complaints are frequent in older adults and are associated with higher risk of cognitive decline.

OBJECTIVE

 To investigate the functional outcome of individuals with memory complaints followed up at primary care centers.

METHODS

 Data were collected between 2016 e 2020 in primary health care centers in Brazil. Patients underwent the Brief Cognitive Screening Battery, and the Functional Activities Questionnaire.

RESULTS

 The initial sample (2016) comprised 91 individuals classified into those with subjective cognitive decline (SCD, n = 15), mild cognitive impairment (MCI, n = 45), or dementia (n = 31). During follow-up, 8 individuals (8.8% of the initial sample) died and 26 (28.5% of the initial sample) were not found. Fifty-seven participants underwent clinical reassessment. Of 15 individuals with SCD, 7 were not found (46.7%), 4 (26.7%) progressed to MCI, and 4 (26.7%) remained stable. Of 45 individuals with MCI, 11 were not found (24.4%), 2 (4.4%) died, 6 (13.4%) progressed to dementia, 12 (26.7%) regressed to SCD, and 14 (31.1%) remained stable. Of 31 individuals with dementia, 8 were not found (25.8%), 6 (19.4%) died, 2 (6.5%) regressed to SCD, 7 (22.6%) regressed to MCI, and 8 remained stable (25.8%). Clinical improvement was due to the treatment of reversible causes, such as B12 hypovitaminosis and mood disorders. Older age, lower Mini-Mental State Examination, and higher scores of memory complaint, but not the use of benzodiazepines and of proton pump inhibitors, were predictors of functional status.

CONCLUSION

 Despite their limits (short sample size, missing data), these results support the idea that adequate screening, follow-up, and treatment of reversible causes of dementia in primary care are essential.

Impaired lexical access for unique entities in individuals with subjective cognitive decline

Subjective cognitive decline (SCD) may serve as an early indicator of Alzheimer's disease (AD). However, accurately quantifying cognitive impairment in SCD is challenging, mainly because existing assessment tools lack sensitivity. This study examined how tasks specifically designed to assess knowledge of famous people, could potentially aid in identifying cognitive impairment in SCD. A total of 60 adults with SCD and 60 healthy controls (HCs) aged 50 to 82 years performed a famous people verbal fluency task and a famous people naming task. In the famous people fluency task, the results showed that the individuals with SCD produced significantly fewer famous names in the total time allowed than the HCs, and this difference was also found in the first and the second time interval. In the famous people naming task, the performance of the SCD group was significantly lower than that of the HC group only in the more recent period of fame. Overall, these results suggest that retrieving the names of famous people was more difficult for people with SCD than for people without cognitive complaints. They also suggest that famous people verbal fluency and naming tasks could be useful in detecting cognitive decline at the preclinical stage of AD.

Art therapies and cognitive function in elderly with subjective cognitive decline: a protocol for a network meta-analysis

INTRODUCTION

Subjective cognitive decline means a decline in the subjective perception of self-cognitive function, which is likely to evolve into mild cognitive impairment and dementia. The number of elderly with subjective cognitive decline has increased, bringing huge burdens and challenges to caregivers and society. With the increase in research on art therapies, some of them have gradually been proven to be effective for cognitive function. Therefore, this study aims to summarise the evidence and identify the best art therapy for elderly with subjective cognitive decline.

METHODS AND ANALYSIS

We will include published randomised controlled trials written in English and Chinese if the intervention is one of the art therapies and applied in people aged 60 and above with subjective cognitive decline. Eight electronic databases, including the Cochrane Central Register of Controlled Trials, PubMed, Web of Science, Elsevier, China BioMedical Literature Database, China National Knowledge Infrastructure, VIP Database and Wanfang Database, will be searched from January 2013 to December 2023. Art therapies will mainly include music therapy, reminiscence therapy, painting therapy, dance therapy, reading therapy, horticultural therapy, museum therapy, calligraphy therapy and so on. The outcome will be cognitive function. Study selection, data extraction and quality assessment will be performed by two reviewers. The risk of bias will be evaluated according to the Cochrane Collaboration's risk-of-bias tool, and the evidence quality will be assessed with the Grading of Recommendations Assessment, Development and Evaluation. Standard pairwise meta-analysis and Bayesian network meta-analysis will be conducted. The probabilities of each art therapy will be ranked based on the surface under the cumulative ranking curve.

ETHICS AND DISSEMINATION

Ethical approval is not required for reviewing published studies. To provide important evidence for clinicians and guideline developers, the findings of this study will be submitted to a peer-reviewed journal.

PROSPERO REGISTRATION NUMBER

CRD42023443773.

Neurocognitive Impairment and Social Cognition in Parkinson's Disease Patients

In addition to motor symptoms, neurocognitive impairment (NCI) affects patients with prodromal Parkinson's disease (PD). NCI in PD ranges from subjective cognitive complaints to dementia. The purpose of this review is to present the available evidence of NCI in PD and highlight the heterogeneity of NCI phenotypes as well as the range of factors that contribute to NCI onset and progression. A review of publications related to NCI in PD up to March 2023 was performed using PubMed/Medline. There is an interconnection between the neurocognitive and motor symptoms of the disease, suggesting a common underlying pathophysiology as well as an interconnection between NCI and non-motor symptoms, such as mood disorders, which may contribute to confounding NCI. Motor and non-motor symptom evaluation could be used prognostically for NCI onset and progression in combination with imaging, laboratory, and genetic data. Additionally, the implications of NCI on the social cognition of afflicted patients warrant its prompt management. The etiology of NCI onset and its progression in PD is multifactorial and its effects are equally grave as the motor effects. This review highlights the importance of the prompt identification of subjective cognitive complaints in PD patients and NCI management.

The Role of Sensory Impairment in Cognitive Health Appraisal: A Study of Older Korean Americans Living in Subsidized Senior Housing

OBJECTIVES

We examined how the association between cognitive performance and cognitive health appraisal would be moderated by vision and/or hearing impairment.

METHODS

Data were collected from 315 older Korean-American residents in subsidized senior housing in Los Angeles (M age = 79.4 years). Linear regression models examined the direct and interactive effects of cognitive performance, vision impairment, and hearing impairment on cognitive health appraisal.

RESULTS

Negative appraisal of cognitive health was associated with lower cognitive performance and poorer ratings for vision and hearing. Moreover, we found a significant interaction between cognitive performance and hearing impairment (β = .13, p < .05), as well as a three-way interaction among cognitive performance, vision impairment, and hearing impairment (β = .12, p < .05).

DISCUSSION

The association between objective and subjective measures of cognition was weakened when hearing was impaired. Such a pattern was further evident when both vision and hearing were impaired.

Effect of increasing cognitive activity participation on default mode network in older adults with subjective cognitive decline: a randomised controlled trial

BACKGROUND

Having more cognitive activities may prevent dementia, but its evidence of modulating the functional brain network is limited. This randomised controlled trial (RCT) investigated the effect of increased cognitive activity participation on the default mode network (DMN) in older adults who had already been having regular cognitive activity participation and experiencing subjective cognitive decline (SCD).

METHODS

Community-living Chinese individuals aged 55-75 years with regular practice of Chinese calligraphy and screened positive for SCD (but negative for mild cognitive impairment or dementia) were randomly allocated to either the intervention or control group. Over 6 months, the intervention group doubled their weekly calligraphy practice time, while the control group maintained their usual amount of practice. The primary outcome was functional connectivities (FCs) of DMN, with pre-specified regions of interest including medial prefrontal cortex (mPFC), inferior parietal lobe (IPL), hippocampal formation (HF), posterior cingulate cortex (PCC), and lateral temporal cortex (LTC). FC changes were compared using repeated measures multivariate analysis of variance (MANOVA). This study is registered at the Chinese Clinical Trial Registry, ChiCTR1900024433.

FINDINGS

Between 15 January 2020 and 31 December 2021, 112 individuals consented and completed the baseline assessment. The participants, who had a mean age of 66.3 (SD 4.3) years, with 83 (74%) being women, had been practising calligraphy for an average duration of 9.7 years before enrolment and, in the preceding six months, for an average of 3.1 hours per week. 96 (86%) completed the post-intervention fMRI scan. Significant between-group differences were observed in the FCs between mPFC and right LTC (group difference = 0.25 [95% CI = 0.06-0.44], p = 0.009), mPFC and right IPL (0.23 [0.06-0.39]; p = 0.007), left HF and right LTC (0.28 [0.002-0.57]; p = 0.04), and left HF and right IPL (0.34 [0.09-0.60]; p = 0.009).

INTERPRETATION

Our findings, which reveal positive neuromodulatory effects with increased calligraphy practice, highlight the importance of engaging more in cognitive activities in late life for better brain health.

FUNDING

Research Grants Council, Hong Kong (grant number 24114519).

Fornix fractional anisotropy mediates the association between Mediterranean diet adherence and memory four years later in older adults without dementia

Here, we investigated whether fractional anisotropy (FA) of hippocampus-relevant white-matter tracts mediates the association between baseline Mediterranean diet adherence (MeDiAd) and verbal episodic memory over four years. Participants were healthy older adults with and without subjective cognitive decline and patients with amnestic mild cognitive impairment from the DELCODE cohort study (n = 376; age: 71.47 ± 6.09 years; 48.7 % female). MeDiAd and diffusion data were obtained at baseline. Verbal episodic memory was assessed at baseline and four yearly follow-ups. The associations between baseline MeDiAd and white matter, and verbal episodic memory's mean and rate of change over four years were tested with latent growth curve modeling. Baseline MeDiAd was associated with verbal episodic memory four years later (95 % confidence interval, CI [0.01, 0.32]) but not with its rate of change over this period. Baseline Fornix FA mediated - and, thus, explained - that association (95 % CI [0.002, 0.09]). Fornix FA may be an appropriate response biomarker of Mediterranean diet interventions on verbal memory in older adults.

Can motor decline be a modifiable marker of clinical progression in subjective cognitive decline? A national prospective cohort study

OBJECTIVES

Subjective cognitive decline represents a critical stage for preventing mild cognitive impairment and dementia, but the links between clinical progression in the subjective cognitive decline stage and various motor functions remain inconclusive. This cohort study aimed to elucidate the independent and joint associations between the clinical progression of subjective cognitive decline and motor functions.

METHODS

We enrolled 4880 community-dwelling elderly participants from a national cohort and used Cox proportional hazard regression model and restricted cubic spline models to explore the longitudinal associations between motor functions (gait, strength, balance, and endurance) and the clinical progression of subjective cognitive decline.

RESULTS

During 5-years follow-up, 1239 participants experienced clinical progression. After adjusting for demographics, vascular burden, body components, and polypharmacy, gait speed [hazard ratios (HRs)= 0.96, 95% confidence interval (CI) 0.94-0.99], chair stand test (HRs=1.02, 95%CI 1.01-1.03), and endurance limitation in jogging 1 kilometer (HRs=1.18, 95%CI 1.04-1.34) were significantly associated with clinical progression. Among all participants, individuals characterized by poor upper- and lower-body strength, as well as those with slow pace and reduced endurance, faced the highest risk of cognitive impairment.

CONCLUSIONS

This study emphasizes the potential of gait speed, muscle strength, and endurance as non-cognitive indicators of clinical progression in subjective cognitive decline. Understanding their combined effectiveness may reveal primary physiological mechanisms contributing to the dual decline of motor and cognition.