Subjective Cognitive Decline and Related Cognitive Deficits

Accurate identification of individuals with subjective cognitive decline using 3D regional fractal dimensions on structural magnetic resonance imaging

BACKGROUND AND OBJECTIVE

Accurate identification of individuals with subjective cognitive decline (SCD) is crucial for early intervention and prevention of neurodegenerative diseases. Fractal dimensionality (FD) has emerged as a robust and replicable measure, surpassing traditional geometric metrics, in characterizing the intricate fractal geometrical properties of brain structure. Nevertheless, the effectiveness of FD in identifying individuals with SCD remains largely unclear. A 3D regional FD method can be suggested to characterize and quantify the spatial complexity of the precise gray matter, providing insights into cognitive aging and aiding in the automated identification of individuals with SCD.

METHODS

This study introduces a novel integer ratio based 3D box-counting fractal analysis (IRBCFA) to quantify regional fractal dimensions (FDs) in structural magnetic resonance imaging (MRI) data. The innovative method overcomes limitations of conventional box-counting techniques by accommodating arbitrary box sizes, thereby enhancing the precision of FD estimation in small, yet neurologically significant, brain regions.

RESULTS

The application of IRBCFA to two publicly available datasets, OASIS-3 and ADNI, consisting of 520 and 180 subjects, respectively. The method identified discriminative regions of interest (ROIs) predominantly within the limbic system, fronto-parietal region, occipito-temporal region, and basal ganglia-thalamus region. These ROIs exhibited significant correlations with cognitive functions, including executive functioning, memory, social cognition, and sensory perception, suggesting their potential as neuroimaging markers for SCD. The identification model trained on these ROIs demonstrated exceptional performance achieving over 93 % accuracy on the discovery dataset and exceeding 87 % on the independent testing dataset. Furthermore, an exchange experiment between datasets revealed a substantial overlap in discriminative ROIs, highlighting the robustness of our method across diverse populations.

CONCLUSION

Our findings indicate that IRBCFA can serve as a valuable tool for quantifying the spatial complexity of gray matter, providing insights into cognitive aging and aiding in the automated identification of individuals with SCD. The demonstrated generalizability and robustness of this method position it as a promising tool for neurodegenerative disease research and offer potential for clinical applications.

Traumatic Brain Injury and Genetic Risk for Alzheimer's Disease Impact Cerebrospinal Fluid β-Amyloid Levels in Vietnam War Veterans

Traumatic brain injuries (TBIs) may increase the risk for Alzheimer's disease (AD) and its neuropathological correlates, although the mechanisms of this relationship are unclear. The current study examined the synergistic effects of TBI and genetic risk for AD on β-amyloid (Aβ) levels among Vietnam War Veterans. We hypothesized that the combination of TBI and higher polygenic risk score (PRS) for AD would be associated with lower cerebrospinal fluid (CSF) Aβ42/40. Data were obtained from the Department of Defense Alzheimer's Disease Neuroimaging Initiative. Participants included Vietnam War Veterans without dementia who identified as White non-Hispanic/Latino and had available demographic, clinical assessment, genetic, and CSF biomarker data. Lifetime TBI history was assessed using The Ohio State University TBI Identification Method. Participants were categorized into those with and without TBI. Among those with a prior TBI, injury severity was defined as either mild or moderate/severe. CSF Aβ42/40 ratios were calculated. Genetic propensity for AD was assessed using PRSs. Hierarchical linear regression models examined the interactive effects of TBI and PRS for AD on Aβ42/40. Exploratory analyses examined the interaction between TBI severity and PRS. The final sample included 88 male Vietnam War Veterans who identified as White non-Hispanic/Latino (M age = 68.3 years), 49 of whom reported a prior TBI. There was a significant interaction between TBI and PRS, such that individuals with TBI and higher PRS for AD had lower Aβ42/40 (B = -0.45, 95% CI: -0.86 to -0.05, p = 0.03). This relationship may be stronger with increasing TBI severity (p = 0.05). Overall, TBI was associated with lower Aβ42/40, indicating greater amyloid deposition in the brain, in the context of greater polygenic risk for AD. These findings highlight who may be at increased risk for AD neuropathology following TBI.

Audiovisual integration and sensory dominance effects in older adults with subjective cognitive decline: Enhanced redundant effects and stronger fusion illusion susceptibility

INTRODUCTION

Subjective cognitive decline (SCD) refers to individuals' perceived decline in memory and/or other cognitive abilities relative to their previous level of performance. Sensory decline is one of the main manifestations of decline in older adults with SCD. The efficient integration of visual and auditory information, known as audiovisual integration, is a crucial perceptual process. This study aims to evaluate audiovisual integration in older adults with SCD.

METHODS

We adopted the audiovisual detection task, the Colavita task, and the Sound-Induced Flash Illusion (SIFI) task to evaluate the audiovisual integration by examining both redundant and illusory effects. Older adults diagnosed with SCD (N = 50, mean age = 67.8 years) and a control group of non-SCD older adults (N = 51, mean age = 66.5 years) were recruited. All participants took part in the three aforementioned experiments.

RESULTS

The outcomes showed that a redundant effect occurred in both SCD and non-SCD older adults, with SCD older adults gaining more benefits in audiovisual detection task. Moreover, an equivalent amount of the visual dominance effect was observed among both SCD and non-SCD older adults in Colavita task. In addition, older adults with SCD perceived an equal fission illusion but a bigger fusion illusion compared with non-SCD older adults in SIFI task.

CONCLUSIONS

Overall, older adults with SCD exhibit increased audiovisual redundant effects and stronger fusion illusion susceptibility compared to non-SCD older adults. Besides, visual dominance was observed in both groups via the Colavita task, with no significant difference between non-SCD and SCD older adults. These findings implied that audiovisual integration might offer a potential way for the identification of SCD.

Differentiation between Normal Cognition and Subjective Cognitive Decline in Older Adults Using Discrepancy Scores Derived from Neuropsychological Tests

Several studies have reported subtle differences in cognition between individuals with subjective cognitive decline (SCD) compared to those with normal cognition. This study aimed to (i) identify these differences using discrepancy scores (e.g., categorial-phonemic verbal fluency performance) derived from neuropsychological tests in three cognitive domains (memory: Wechsler's Word List and Digits; executive functions: Stroop and verbal fluency; and language: BNT and ECCO_Senior) and (ii) determine which discrepancy scores are significant for classification. Seventy-five older adults were included: 32 who were labeled SCD+ (age 71.50 ± 5.29), meeting Jessen et al.'s criteria, and 43 in the normal cognition group (SCD-; age 69.81 ± 4.62). Both groups completed a protocol including screening and the specified neuropsychological tests. No differences were found between the groups in their age, education, episodic memory, global cognitive state, or mood. Significant differences between the groups were observed regarding the discrepancy scores derived from BNT (naming) and ECCO_Senior (sentence comprehension). These scores accurately classified participants (71.6%), with ECCO_Senior having a primary role. ROC curves indicated a poor-to-fair model quality or diagnostic accuracy (AUC_BNT = 0.690; AUC_ECCO = 0.722). In conclusion, discrepancy scores in the language domain are important for distinguishing between individuals with SCD and normal cognition, complementing previous findings in this domain. However, given their relatively poor diagnostic accuracy, they should be used with caution as part of a more detailed neuro-psychological assessment.

Predictors of cognitive change in cognitively healthy older women in Panama: the PARI-HD study

Background

Evidence suggests that a combination of biological and social factors influence risk of dementia differently for women and men. In healthy older women, several factors may contribute to changes in cognition.

Objective

Describe the characteristics associated with variation in cognition in a sample of cognitively healthy older Panamanian women.

Methods

The study includes cross-sectional analyses of cognitive domains at baseline (n = 357) and 17-month (SD = 2.0) follow-up (n = 200) for women aged 60 years and older enrolled in the Panama Aging Research Initiative-Health Disparities (PARI-HD) study. Instruments included clinical questionnaires, physiological measures, and a neuropsychological test battery assessing global cognition and seven cognitive domains. Multiple regression analyses examined the associations between demographic and clinical characteristics and cognition at baseline. Repeated measures analyses were used to investigate changes in cognition from baseline to follow-up.

Results

On average, participants were 68.6 years of age (SD = 5.9) with 16.1 years of education (SD = 4.7). Age, income, and education showed robust associations with baseline cognition. Subjective cognitive impairment was associated with lower performance in global cognition, verbal learning, and memory domains. Only performance in the attention domain decreased at follow-up, and subjective health state and depressive symptoms significantly predicted the change in attention.

Discussion

Our study findings contribute to the investigation of cognitive health in older Hispanic women and to the understanding of sociodemographic and health-related factors associated with cognitive decline and the progression to cognitive impairment and dementia.

Psychometric properties and normative data of the Italian version of the Cognitive Function at Work Questionnaire: a screening tool for detecting subjective cognitive complaints at work

INTRODUCTION

Considering the extension of working life due to socioeconomic and political factors, many people may experience cognitive complaints (CC) at their workplace, with severe consequences on their quality of life. The identification of workers reporting significative SCC is crucial to eventually address them to an objective neuropsychological evaluation and implement cognitive interventions to guarantee workers' well-being. Since no Italian questionnaires for detecting CC were designed for occupational settings, the aim of the study was to validate the Italian version of the Cognitive Function at Work Questionnaire (CFWQ) and to provide its normative data.

MATERIALS AND METHODS

Internal consistency, convergent and divergent validity, and factorial structure of the CFWQ were evaluated. A regression-based procedure served to compute percentiles of CFWQ and its subscales.

RESULTS

Four hundred twenty-one participants without psychiatric and/or neurological disorders completed the survey. We found that the Italian CFWQ included 26 items, with a good internal consistency (Cronbach's alpha = 0.897) and a six-factor structure (memory, language, processing speed, abstract thinking/behavioral control, behavioral inertia, planning ability). CFWQ score did not correlate with empathy but correlated strongly with memory scores and moderately with anxiety and depression scores.

CONCLUSIONS

The Italian CFWQ showed good psychometric properties, in analogy with the original English scale. Therefore, it can be successfully employed in organizational contexts to possibly identify workers with CC and therefore with possible co-occurrent psychological, behavioral, and cognitive consequences.

Association Between Subjective Cognitive Decline and Twice-Weekly Muscle-Strengthening Activities in Middle-Aged and Older US Adults: An Analysis of the 2019 Behavioral Risk Factor Surveillance System

PURPOSE

Adults with subjective cognitive decline (SCD), the self-reported concern of reduced cognitive function, are recommended to do physical activity for its brain health benefits. US adults aged ≥45 with SCD are less likely to meet the American College of Sports Medicine (ACSM) aerobic activity recommendations. Their engagement in muscle-strengthening activities is unknown. We aimed to identify if US adults aged ≥45 with SCD are less likely to do twice-weekly muscle-strengthening activities compared to those without SCD.

DESIGN

Secondary analysis of the 2019 Behavioral Risk Factor Surveillance System (BRFSS) data.

SAMPLE

114 164 respondents, representing approximately 59 million US adults aged ≥45.

MEASURES

SCD was indicated if the respondent reported confusion or memory loss during the past 12 months (yes/no). Respondents reported the frequency of muscle-strengthening activities, which we categorized as meeting the ACSM's recommendations (2+ times per week) or not (<2 times per week).

ANALYSIS

Crude and adjusted logistic regression models controlling for variables associated with SCD and muscle-strengthening activities. The models used sample weights to represent US adults in the included 31 states and Washington D.C.

RESULTS

US adults aged ≥45 with SCD were less likely to do twice-weekly muscle-strengthening activities than those without SCD (28.6% [SE: .8%] vs 33.5% [SE: .3%], adjusted OR, .9; 95% CI: .9-1.0).

CONCLUSION

Primary care providers should encourage middle-aged and older patients to engage in muscle-strengthening and aerobic activities.

A household survey of the prevalence of subjective cognitive decline and mild cognitive impairment among urban community-dwelling adults aged 30 to 65

While it is possible to detect cognitive decline before the age of 60, and there is a report indicating that certain cognitive abilities peak in one's 30s, the evidence regarding cognitive problems in populations younger than 65 years is scarce. This study aims to (1) determine the proportion of community-dwelling adults with different cognitive status, and (2) determine the prevalence of neuropsychiatric behaviors. A population-based survey was conducted in Chiang Mai, Thailand. Individuals aged 30 to 65 were recruited and assessed for demographic data, memory complaints, cognitive performance, and neuropsychiatric symptoms using self-reported questionnaires. In a total of 539 participants, 33.95% had mild cognitive impairment (MCI), 7.05% had subjective cognitive decline (SCD), and 52.50% had neuropsychiatric symptoms. The risk of MCI increased with age, and neuropsychiatric symptoms were significantly higher in those with MCI or SCD than in those without (p < 0.001). The most common complaints were sleep problems, anxiety, and irritability. Screening for MCI in adults aged < 65 years might be useful. However, further investigation on the appropriate age to screen and the program's cost-effectiveness is suggested.

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.

Predictors of progression from subjective cognitive decline to objective cognitive impairment: A systematic review and meta-analysis of longitudinal studies

BACKGROUND

Subjective cognitive decline is one of the first symptoms of dementia. With increasing awareness of brain health and a rising prevalence of dementia, a growing number of individuals seek medical assistance for purely subjective cognitive decline. However, only individuals with specific characteristics tend to experience clinical progression.

OBJECTIVES

This study aims to summarize the predictors of objective cognitive impairment in individuals with subjective cognitive decline and to identify those at higher risk of clinical progression.

DESIGN

Systematic review and meta-analysis.

METHODS

We systematically searched 11 electronic databases from inception to February 1, 2023, for longitudinal studies investigating factors associated with the clinical progression of subjective cognitive decline. Effect sizes were pooled using fixed-effects and random-effects models. Leveraging the results of the meta-analysis, we developed two risk prediction models for objective cognitive impairment.

RESULTS

Forty-six cohort studies were included in the systematic review, of which 28 met the meta-analysis criteria. Fifteen predictors were identified, including 4 biomarkers (amyloid β deposition, lower Hulstaert Formula scores, apolipoprotein e4, and hippocampus atrophy), four epidemiological factors (older age at baseline, impaired instrumental activity of daily living, depression, and anxiety), and seven neuropsychological factors (participants in clinical settings, older age at onset, stable symptom, concerns, cognitive decline confirmed by informant, severe symptoms, and poor performance on Trail Making Test B). Based on the meta-analysis results, we developed two risk prediction models. The first model (Model1) incorporates epidemiological and neuropsychological factors, distinguishing individuals with low and medium risk. The second model (Model2) includes additional biomarkers to enhance predictive performance and identify individuals at high risk.

CONCLUSIONS

This study provides a comprehensive characterization of individuals undergoing clinical progression from subjective cognitive decline to mild cognitive impairment or dementia. The developed models support the prediction of progression risk in both memory clinic and community settings, aiding in the early identification of individuals at risk of disease conversion and facilitating the translation of evidence into clinical practice.

REGISTRATION

The systematic review and meta-analysis have been registered in PROSPERO (CRD 42023392476).

TWEETABLE ABSTRACT

Factors for predicting progression from subjective cognitive decline to objective cognitive impairment: evidence from longitudinal studies.

The Shape Trail Test Is Sensitive in Differentiating Older Adults with Mild Cognitive Impairment: A Culture-neutral Five-minute Test

INTRODUCTION

The Shape Trail Test (STT) was developed based upon the Trail Making Test, as a culture-neutral test for measuring processing speed and mental flexibility. This study aims to evaluate the accuracy and validity of this five-minute test for differentiating individuals with normal cognition (NC), subjective memory impairment (SMI), and mild cognitive impairment (MCI).

METHOD

The study included 210 participants aged 50-80 years, with 70 participants in each group matched for age, education, and gender.

RESULTS

No significant difference in STT measures was found between the NC and SMI groups. In contrast, both the NC and SMI groups exhibited significantly better performance (shorter completion time in STT-A and STT-B and fewer STT-B errors) than the MCI group. No significant group differences were found in STT-A errors. Stepwise regression analysis identified three significant predictors for classifying the MCI group from the NC and/or SMI groups, including the STT-B completion time, the STT-A errors, and the interaction between STT-B completion time and STT-B errors. The composite score of these three predictors demonstrated good discriminatory power for classifying the MCI group from the other groups, with area under the curves (AUCs) of 0.76 - 0.79 (p < 0.001), sensitivities of 78.6% - 80%, and specificities of 60% - 61.4%. However, none of the STT measures or their interactions were significant predictors for differentiating the SMI group from the NC group. Besides, the STT measures were significantly correlated with age, education, and executive function measures.

DISCUSSION

The STT could be a culture- and language-free, reliable test for assessing executive function and a sensitive test for predicting MCI.

The Effects of Different Exercise Interventions on Patients with Subjective Cognitive Decline: A Systematic Review and Network Meta-Analysis

BACKGROUND AND OBJECTIVE

Exercise is a promising non-pharmacological therapy for subjective cognitive decline, but it is unclear which type of exercise is most effective. The objective was to assess the comparative effects and ranks of all exercise-based interventions on cognitive function in patients with subjective cognitive decline (SCD).

METHOD

In this network meta-analysis, Online databases for Web of Science, PubMed, Embase, Medline, Cochrane Library and PsycINFO were searched from inception to April 30, 2023. The included studies are randomized controlled trials assessing the efficacy of exercise interventions for individuals with SCD. The primary outcome measure is memory, while secondary outcome measures encompass executive function, attention, verbal fluency, and global cognitive function. Represented using Standardized Mean Differences (SMDs) along with their 95% Confidence Intervals (CIs). Bias assessment was conducted in accordance with the 'Cochrane Risk of Bias Assessment Tool, 2nd Edition' (RoB 2). Pairwise meta-analysis was carried out using the 'meta-analysis' module within STATA 14.0, and network meta-analysis was performed using the 'mvmeta' and 'network' packages available in STATA 14.0. Registration number CRD42023289687.

RESULT

This study included a total of 11 randomized controlled trials, encompassing 1,166 patients. Mind-body exercise was found to be efficacious in enhancing or sustaining memory (SMD: 0.58, 95%CI: 0.06 ~ 1.10) and executive function (SMD: 0.41, 95%CI: 0.09 ~ 0.73) in individuals with subjective cognitive decline. Furthermore, mind-body exercise exhibited the highest probability of being the most effective measures for improving or preventing the decline in memory (surface under cumulative ranking curve (SUCRA) value: 90.4) and executive function (SUCRA value: 91.8). The second-ranked moderate-intensity aerobic exercise has also shown a positive effect on the improvement of executive function in patients with subjective cognitive decline (SMD: 0.23, 95%CI: 0.03 ~ 0.43, SUCRA value: 68.2). However, we did not observe a significant effectiveness of exercise interventions on verbal fluency, attention, and overall cognitive function in subjective cognitive decline.

CONCLUSION

Mind-body exercise may potentially be the optimal strategies for enhancing memory and executive function in individuals with subjective cognitive decline. Additionally, moderate-intensity aerobic exercise has shown a modest positive effect on executive function in subjective cognitive decline. When resources permit, practical application of these findings may be considered. Nevertheless, further support for the conclusions of this study is warranted through larger sample sizes and well-designed multicenter trials.

Clinical subtypes in patients with isolated REM sleep behaviour disorder

Patients with Parkinson's disease (PD) show a broad heterogeneity in clinical presentation, and subtypes may already arise in prodromal disease stages. Isolated REM sleep behaviour disorder (iRBD) is the most specific marker of prodromal PD, but data on clinical subtyping of patients with iRBD remain scarce. Therefore, this study aimed to identify iRBD subtypes. We conducted comprehensive clinical assessments in 66 patients with polysomnography-proven iRBD, including motor and non-motor evaluations, and applied a two-step cluster analysis. Besides, we compared iRBD clusters to matched healthy controls and related the resulting cluster solution to cortical and subcortical grey matter volumes by voxel-based morphometry analysis. We identified two distinct subtypes of patients based on olfactory function, dominant electroencephalography frequency, amount of REM sleep without atonia, depressive symptoms, disease duration, and motor functions. One iRBD cluster (Cluster I, late onset-aggressive) was characterised by higher non-motor symptom burden despite shorter disease duration than the more benign subtype (Cluster II, early onset-benign). Motor functions were comparable between the clusters. Patients from Cluster I were significantly older at iRBD onset and exhibited a widespread reduction of cortical grey matter volume compared to patients from Cluster II. In conclusion, our findings suggest the existence of clinical subtypes already in the prodromal stage of PD. Future longitudinal studies are warranted that replicate these findings and investigate the risk of the more aggressive phenotype for earlier phenoconversion and dementia development.

Effects of repetitive transcranial magnetic stimulation on episodic memory in patients with subjective cognitive decline: study protocol for a randomized clinical trial

Introduction

Early decline of episodic memory is detectable in subjective cognitive decline (SCD). The left dorsolateral prefrontal cortex (DLPFC) is associated with encoding episodic memories. Repetitive transcranial magnetic stimulation (rTMS) is a novel and viable tool to improve cognitive function in Alzheimer's disease (AD) and mild cognitive impairment, but the treatment effect in SCD has not been studied. We aim to investigate the efficacy of rTMS on episodic memory in individuals with SCD, and to explore the potential mechanisms of neural plasticity.

Methods

In our randomized, sham-controlled trial, patients (n = 60) with SCD will receive 20 sessions (5 consecutive days per week for 4 weeks) of real rTMS (n = 30) or sham rTMS (n = 30) over the left DLPFC. The primary outcome is the Auditory Verbal Learning Test-Huashan version (AVLT-H). Other neuropsychological examinations and the long-term potentiation (LTP)-like cortical plasticity evaluation serve as the secondary outcomes. These outcomes will be assessed before and at the end of the intervention.

Discussion

If the episodic memory of SCD improve after the intervention, the study will confirm that rTMS is a promising intervention for cognitive function improvement on the early stage of dementia. This study will also provide important clinical evidence for early intervention in AD and emphasizes the significance that impaired LTP-like cortical plasticity may be a potential biomarker of AD prognosis by demonstrating the predictive role of LTP on cognitive improvement in SCD.

Ethics and dissemination

The study was approved by the Human Research Ethics Committee of the hospital (No. 2023-002-01). The results will be published in peer-review publications.

Clinical trial registration

https://www.chictr.org.cn/, identifier ChiCTR2300075517.

Normative Data for a Neuropsychological Test Battery in the French Aging Population: 20-Year Follow-Up From the "PROgnostic OF Cardiovascular and Cerebrovascular Events" Study

OBJECTIVE

The study aimed to present relevant norms for the evaluation of pathological aging in the French population over a 20-year period, utilizing the "PROgnostic OF cardiovascular and cerebrovascular events" test and questionnaire.

METHODS

Three neuropsychological evaluations were administered over 20 years with 929 participants at the first cognitive evaluation (62-69 years old), 631 at the second (71-78 years old), and 293 at the third (81-88 years old). The tests and questionnaires were administered in the following order: McNair's Cognitive Complaints Questionnaire, Depression Questionnaire of Pichot, Mini Mental State Examination, Free and Cued Selective Reminding test, Benton Visual Retention Test, Digit-Symbol Substitution Test of the WAIS-III, Trail Making Test, Stroop Test, Verbal Fluency, and the Similarities subtest of the WAIS-III.

RESULTS

Normative data were presented at three time points of the repeated evaluation over 20 years (62-69 years, 71-78 years, and 81-88 years) and four educational levels (no diploma, primary school certificate, certificate of professional aptitude, and baccalaureate and above). The data showed a significant effect of educational level in all neuropsychological tests regardless of age. Gender primarily affected memory, Stroop scores, and Similarities scores.

CONCLUSION

This study highlights the importance of educational level and gender in the evaluation of the memory and executive function of elderly persons. Furthermore, the presented norms consider the self-report cognitive complaints and depression symptoms over a long period of life.

A systematic review of the safety and efficacy on cognitive function of herbal and nutritional medicines in older adults with and without subjective cognitive impairment

BACKGROUND

Subjective cognitive impairment (SCI) substantially increases dementia risk and is often conceptualised as the preclinical asymptomatic phase of the cognitive decline continuum. Due to the lack of pharmacological interventions available to treat SCI and reduce dementia risk, and the popularity of herbal and nutritional medicines, the primary aim of this review was to investigate the efficacy on cognitive function and safety of herbal and nutritional medicines (relative to a control) for older adults with and without SCI. The secondary aims were to describe the study characteristics and assess the methodological quality of included studies.

METHOD

Five databases (Cochrane, MEDLINE, CINAHL, PsycInfo, and EMBASE) were searched from database inception with weekly alerts established until review finalisation on 18 September 2022. Articles were eligible if they included the following: study population of older adults with and without SCI, herbal and nutritional medicines as an intervention, evaluated cognitive outcomes and were randomised control trials.

RESULTS

Data were extracted from 21/7666 eligible full-text articles, and the risk of methodological bias was assessed (with SCI = 9/21; without SCI = 12/21). Most studies (20/21) employed parallel, randomised, placebo-controlled designs and were 12 weeks in length. Herbal supplements were widely used (17/21), namely a form of Ginkgo biloba (8/21) or Bacopa monnieri (6/21). Measures of cognition varied across studies, with 14/21 reporting improvements in at least one domain of cognitive functioning over time, in the intervention group (compared to control). A total of 14/21 studies were deemed as having an overall high methodological risk of bias, 6/21 had some concerns, and only one study (using an SCI population) was assessed as having a low risk of methodological bias.

CONCLUSIONS

Overall, this review found that there is a low quality of evidence regarding the efficacy of cognitive function and safety of herbal and nutritional medicines for older adults with and without SCI, due to a high risk of bias across studies. Additionally, further work needs to be done in classifying and understanding SCI and selecting appropriate trial primary outcomes before future studies can more accurately determine the efficacy of interventions for this population.

Association between social isolation and subjective cognitive decline in Korean older adult population: A nationwide cross-sectional study in South Korea

This study aimed to analyze the association between social isolation (SI) and subjective cognitive decline (SCD) in Koreans aged 65 years or older. The cross-sectional study of the Korea Community Health Survey (KCHS) was conducted on 72,904 individuals aged 65 years or older. SI was defined using five indicator, and an increasing number of SI indicators signifies a higher level of SI. SCD was defined as self-observed impairment of more frequent or worsening memory loss or confusion within the previous 12 months. The cognitive function questionnaire included questions regarding SCD. Chi-square test and weighted logistic regression analysis were used to analyze the association between SI and SCD. SI group had higher odds of SCD experience rate than the non-SI (AOR:1.15, 95 % CI: 1.08-1.22). Subgroup analysis showed that when SI occurred in the non-Moderate or Vigorous Physical Exercise (MVPE) group, SI group was more likely to experience SCD compared with the non-SI (AOR: 1.17, 95 % CI: 1.10-1.25). However, when SI occurred in the MVPE group, there were not find out the association between SI and SCD. The results of this study showed that the SI group had a higher rate of SCD than the non-SI group. Particularly, a strong association was observed in the non-MVPE. Therefore, even if SI occurs, SCD can be prevented by educating individuals regarding the importance of participating in MVPE and depression.

Mental Fatigue Is Associated with Subjective Cognitive Decline among Older Adults

Both Subjective Cognitive Decline (SCD) and mental fatigue are becoming increasingly prevalent as global demographics shifts indicate our aging populations. SCD is a reversible precursor for Alzheimer's disease, and early identification is important for effective intervention strategies. We aim to investigate the association between mental fatigue-as well as other factors-and SCD. A total of 707 old adults (aged from 60 to 99) from Shanghai, China, participated in this study and completed self-reported instruments covering their cognitive and mental status as well as demographic information. Mental fatigue status was assessed by using four items derived from the functional impairment syndrome of the Old Adult Self Report (OASR). SCD was assessed by using the Memory/Cognition syndrome of OASR. A total of 681 old adults were included in the current study. The means of SCD significantly differed between each group of factors (age, gender, and mental fatigue). The general linear regression models showed that SCD increased with age, females scored higher than males, and SCD was positively associated with mental fatigue factors including difficulty getting things done, poor task performance, sleeping more, and a lack of energy among old adults. The study also found that SCD is negatively associated with the high-income group among young-old (aged from 60 to 75) males and associated with good marital/living status with the companion of spouses/partners among young-old females. These results suggest that gender, income level, marital/living status, and mental fatigue are crucial factors in preventing SCD among old adults and are pivotal in developing early intervention strategies to preserve the mental health of an increasingly aging population.

The association between low cognitive reserve and subjective memory complaints in functionally independent older women

BACKGROUND

Several factors have been found to defend against pathologic cognitive decline in aging (i.e., cognitive reserve [CR]); however, other factors, including subjective memory complaints (SMC) and decreased functionality are considered early indicators of underlying neurocognitive dysfunction. Despite these known associations, the relationship between the presence of CR and SMC remains equivocal. This study sought to determine the relationship between objectively measured CR and SMC in a sample of functionally independent older women.

METHODS

This cross-sectional study recruited women aged ≥60 years who attended fitness or continuing education programs at the University for Seniors in Mexico City. Participants underwent a battery of physical and cognitive evaluations, including the Cognitive Reserve Questionnaire (CRQ), and were asked probing questions used to identify the presence of SMC.

RESULTS

The 269 participants had a median age of 69 years; most were single (40.5 %), lived alone (32.7 %), retired (58.2 %), well-educated (≥12 years of education), and functionally independent (89.2 %). 62 % scored "high" on the CRQ, while 9.3 % scored "low". After adjusting for multiple covariates, an independent association between CRQ score and the probability to have SMC was found (adjusted OR = 0.87, 95% CI 0.80-0.95, p-value = 0.002).

CONCLUSIONS

This study identified a relationship between low CR and the presence of SMC, independently of the cognitive function and motoric marker of muscle strength (i.e., low gait speed and handgrip strength) in functionally independent older women over 60y. This relationship remains independent of other variables such as age, symptoms of depression and instrumented activities of daily living.

Psychometric Properties of the Subjective Cognitive Decline Questionnaire (SCD-Q) and Its Invariance across Age Groups

Considering that a good sense of subjective cognitive decline seems to be crucial to prevent decline before clinical impairment, the interest in examining tools on this front were raised in the last decade. The aim of the present study is to examine the psychometric properties of the Subjective Cognitive Decline Questionnaire (SCD-Q) across age in its Spanish adaptation. It should be noted that two constructs were proposed in this context: mnestic processes and executive function factors. For this reason, a sample of 750 individuals aged from 18 to 82 years participated in the study. They were divided into three different groups: young, middle, and older adults. A confirmatory factor analysis (CFA) and invariance analysis were carried out. Moreover, a logistic regression was employed to address the role of age. The results support a good goodness of fit for both uni- and bifactorial models. The invariance analysis reached the structural covariances levels. Last, age did not predict the recognition of cognitive decline in the last two years, while the SCD-Q bifactorial model did. These results are of interest both on a theoretical level, to provide more information on models of cognitive impairment, and on a practical level, for screening.

Common Neuropsychiatric S ymptoms in Alzheimer's Disease, Mild Cognitive Impairment, and Subjective Memory Complaints: A Unified Framework

The Alzheimer's disease (AD) continuum is a unique spectrum of cognitive impairment that typically involves the stages of subjective memory complaints (SMC), mild cognitive impairment (MCI), and AD dementia. Neuropsychiatric symptoms (NPS), such as apathy, anxiety, stress, and depression, are highly common throughout the AD continuum. However, there is a dearth of research on how these NPS vary across the AD continuum, especially SMC. There is also disagreement on the effects of specific NPS on each stage of the AD continuum due to their collinearity with other NPS, cognitive decline, and environmental factors (e.g., stress). In this article, we conduct a novel perspective review of the scientific literature to understand the presence of NPS across the AD continuum. Specifically, we review the effects of apathy, depression, anxiety, and stress in AD, MCI, and SMC. We then build on this knowledge by proposing two theories of NPS' occurrence across the AD continuum. Consequently, we highlight the current landscape, limitations (e.g., differing operationalization), and contentions surrounding the NPS literature. We also outline theories that could clear up contention and inspire future NPS research.

[Asthenia, mental fatigue and cognitive dysfunction]

Conditions associated with asthenia are usually characterized by increased fatigue, impaired activities of daily living and decreased productivity. In clinical practice it is important to distinguish between idiopathic chronic fatigue (primary or functional asthenia) and chronic fatigue syndrome (CFS). Fatigue can also be classified by neuromuscular and/or cognitive and mental fatigue. The article discusses the neuroanatomical basis and focuses on the neurocognitive theory of pathological fatigue. In addition the relationship between mental stress, fatigue and cognitive impairments such as subjective cognitive impairment (SCI) and mild cognitive impairment (MCI) are also discussed. We discuss the rationale that for treatment of asthenic conditions accompanied by cognitive dysfunction it is justified to use combination therapy - fonturacetam and a preparation containing nicotinoyl-GABA and Ginkgo Biloba.

MASCoD-Multidimensional Assessment of Subjective Cognitive Decline

Subjective cognitive decline (SCD) is a subclinical cognitive impairment that is complained by the individual without being objectively supported at clinical, diagnostic, and neuropsychological levels. It can negatively impact on patient's frailty and quality of life, as well as on the caregiver's burden. Moreover, it can be prodromal to Mild Cognitive Impairment or dementia. Although the clinical manifestations of SCD can differ along with several cognitive domains, to date there are only screening tools to investigate subjective memory complaints. Thus, the first aim of this paper is to propose a preliminary English and Italian version of a new screening tool called MASCoD (Multidimensional Assessment of Subjective Cognitive Decline); the second aim is to propose its preliminary adoption on a pilot sample. This schedule is a brief test derived from the review of the literature and the clinical experience provided by an experts panelist. From pilot tests, it seems promising as it can help the professional to make differential diagnosis and to predict the risk of developing severe cognitive impairment over time, developing a personalized care path. This screening tool is brief, easily embeddable in usual clinical assessment, and administrable by different professionals. Furthermore, following validation, it will allow to collect manifold cognitive manifestations of SCD, addressing the shortage of previous validated instruments globally assessing cognition affected by this condition.

Percentage amplitude of fluctuation and structural covariance changes of subjective cognitive decline in patients: A multimodal imaging study

Back ground

Subjective cognitive decline (SCD) may be the first clinical sign of Alzheimer’s disease (AD). The possible neural mechanisms of SCD are not well known. This study aimed to compare percent amplitude of fluctuation (PerAF) and structural covariance patterns in patients with SCD and healthy controls (HCs).

Methods

We enrolled 53 patients with SCD and 65 HCs. Resting-state functional magnetic resonance imaging (MRI) data and T1-weighted anatomical brain 3.0-T MRI scans were collected. The PerAF approach was applied to distinguish altered brain functions between the two groups. A whole-brain voxel-based morphometry analysis was performed, and all significant regions were selected as regions of interest (ROIs) for the structural covariance analysis. Statistical analysis was performed using two-sample t-tests, and multiple regressions were applied to examine the relationships between neuroimaging findings and clinical symptoms.

Results

Functional MRI results revealed significantly increased PerAF including the right hippocampus (HIPP) and right thalamus (THA) in patients with SCD relative to HCs. Gray matter volume (GMV) results demonstrated decreased GMV in the bilateral ventrolateral prefrontal cortex (vlPFC) and right insula in patients with SCD relative to HCs. Taking these three areas including the bilateral vlPFC and right insula as ROIs, differences were observed in the structural covariance of the ROIs with several regions between the two groups. Additionally, significant correlations were observed between neuroimaging findings and clinical symptoms.

Conclusion

Our study investigated the abnormal PerAF and structural covariance patterns in patients with SCD, which might provide new insights into the pathological mechanisms of SCD.

APOE ε4 Allele Distribution and Association With Scores of Subjective Cognitive Decline Questionnaire 9 in a Large Chinese Memory Clinic Cohort

Background

Previous reports on APOE ε4 allele distribution in different populations have been inconclusive. The Subjective Cognitive Decline-Questionnaire 9 (SCD-Q9) was developed to identify those at risk of objective cognitive impairment [OCI; including mild cognitive impairment (MCI) and dementia groups), but its association with APOE ε4 and discriminatory powers for SCD_{with subtle cognitive decline} (SCDs) and OCI in memory clinics are unclear.

Objectives

To investigate demographic distribution of APOE ε4, its association with SCD-Q9 scores, and its ability to discriminate SCDs and OCI groups from normal control (NC).

Methods

A total of 632 participants were recruited (NC = 243, SCDs = 298, OCI = 91). APOE ε4 allele distribution and association with SCD-Q9 scores were calculated and the effects on cognitive impairment were analyzed. Receiver operating characteristic (ROC) analysis was applied to identify discriminatory powers for NC, SCDs, and OCI.

Results

Total APOE ε4 frequency was 13.1%. This did not vary by demography but was higher in patients with OCI. The SCD-Q9 scores were higher in APOE ε4 carriers than non-carriers in the OCI group. The area under the curve (AUC) for discriminating from OCI using APOE ε4 were 0.587 and 0.575, using SCD-Q9 scores were 0.738 and 0.571 for NC and SCDs groups, respectively. When we combined APOE ε4 and SCD-Q9 scores into the model, the AUC increased to 0.747 for discriminating OCI from NC. However, when OCI group was split into MCI and dementia groups, only total SCD-Q9 score was the independent affecting factor of MCI.

Conclusion

This study demonstrated that the distribution of APOE ε4 alleles did not vary with different demographic characteristics in a large-scale cohort from a memory clinic. APOE ε4 alleles may be associated with scores of SCD-Q9 reflecting the degree of cognitive complaints but their additional contribution to SCD-Q9 scores is marginal in discriminating between NC, SCDs, and OCI.

Hyperreactivity to uncertainty is a key feature of subjective cognitive impairment

With an increasingly ageing global population, more people are presenting with concerns about their cognitive function, but not all have an underlying neurodegenerative diagnosis. Subjective cognitive impairment (SCI) is a common condition describing self-reported deficits in cognition without objective evidence of cognitive impairment. Many individuals with SCI suffer from depression and anxiety, which have been hypothesised to account for their cognitive complaints. Despite this association between SCI and affective features, the cognitive and brain mechanisms underlying SCI are poorly understood. Here, we show that people with SCI are hyperreactive to uncertainty and that this might be a key mechanism accounting for their affective burden. Twenty-seven individuals with SCI performed an information sampling task, where they could actively gather information prior to decisions. Across different conditions, SCI participants sampled faster and obtained more information than matched controls to resolve uncertainty. Remarkably, despite their ‘urgent’ sampling behaviour, SCI participants were able to maintain their efficiency. Hyperreactivity to uncertainty indexed by this sampling behaviour correlated with the severity of affective burden including depression and anxiety. Analysis of MRI resting functional connectivity revealed that SCI participants had stronger insular-hippocampal connectivity compared to controls, which also correlated with faster sampling. These results suggest that altered uncertainty processing is a key mechanism underlying the psycho-cognitive manifestations in SCI and implicate a specific brain network target for future treatment.

Biopsychosocial Correlates of Subjective Cognitive Decline and Related Worry in the Canadian Longitudinal Study on Aging

INTRODUCTION

Subjective cognitive decline (SCD), a self-reported decline in cognition in otherwise cognitively healthy people, has been acknowledged as a risk factor for Alzheimer's disease. Using data from the Canadian Longitudinal Study on Aging (CLSA), a large national study with participants' ages of 45-85 years at baseline, we sought to identify correlates of SCD and SCD-related worry.

METHODS

In our primary analysis using a Poisson regression model, associations between biopsychosocial variables and SCD were identified (analytic sample: n = 21,920). In a second analysis using an ordinal regression model, associations between biopsychosocial variables and SCD-related worry were identified (analytic sample: n = 12,694).

RESULTS

Multiple risk and protective factors of cognitive decline were not associated with SCD within our sample (i.e., physical activity, hypertension, vision problems), as well as minority stress variables such as sexual orientation and race. Rather, psychosocial variables (i.e., depression, perceived social status, and personality traits) showed a more consistent association with SCD within the sample. Greater SCD-related worry, which is believed to increase the risk of future dementia, was associated with specific personality traits, depression, age, gender, and sexuality.

CONCLUSION

The results from this study confirm the association between multiple health variables and SCD but also emphasize the importance of considering psychological and social factors when conceptualizing SCD and its risk factors.

Characterizing Cognition in Everyday Life of Older Adults With Subjective Cognitive Decline

Subjective cognitive decline (SCD), the subjective experience of worsening cognition with no objective cognitive impairment, poses a heightened risk for dementia. This study aimed to characterize cognition in the everyday life of people with SCD, is crucial for understanding and preventing further functional and cognitive decline. One hundred and thirty-five older adults (age 70.7±6.7) with SCD were assessed using functional-cognition measures: Multifactorial Memory Questionnaire (MMQ), Behavior Rating Inventory of Executive Function–Adult version (BRIEF-A), and Multiple Errands Test (MET). The resulted showed that older adults with SCD reported lower memory satisfaction (Hedges’s g = 0.41) on the MMQ, and worse metacognition on the BRIEF-A (Hedges’s g = 0.63) compared with published normative data. They completed an average of only 6/12 required tasks on the MET. The findings show functional difficulties related to SCD and inform the development of occupational therapy intervention for this population.

Cognitive decline complaints scale (CDCS): validation and normative studies for the adults and older adults Portuguese population

OBJECTIVES

Subjective Cognitive Complaints, which result from the self-perception of Subjective Cognitive Decline, are frequently reported by older adults. The Cognitive Decline Complaints Scale (CDCS) assesses subjective complaints of cognitive decline in several cognitive domains through three levels of severity. This study aims to psychometrically validate this instrument considering the Classical Test Theory, and to establish preliminary normative data of the CDCS for adults and older adults of the Portuguese population.

METHODS

The community-based sample consisted of 199 cognitively healthy Portuguese participants, aged 50 years or older, stratified according to several sociodemographic variables. In addition to the CDCS, all participants responded to an extensive neuropsychological assessment protocol.

RESULTS

The psychometric characteristics of the CDCS were generally adequate for this community sample (e.g. Cronbach's alpha = .936). As for the sociodemographic variables analyzed, only the geographic region showed differences in the CDCS scores, which were more significant in the Azores. There were no significant correlations or differences between the CDCS scores and age and educational level and, therefore, normative data were explored considering the total sample.

CONCLUSION

As a scale, the CDCS allows for the detailed assessment of subjective cognitive complaints and the determination of whether or not such complaints are considered normative, which will facilitate an empirically based understanding of this dimension of psychological functioning and also provide indications as to the need for a more extensive neuropsychological assessment.

Cognitive frailty among community-dwelling rural elderly population of West Bengal in India

OBJECTIVES

There has been growing interest in the links between physical frailty and cognitive impairment: both can increase the risk of emerging life-threatening health problems and are currently prominent within the global geriatric health agenda. A recent consensus proposes the idea of 'cognitive frailty' defined by the presence of both physical frailty and cognitive impairment in the absence of dementia. Present study is intended to determine the prevalence of cognitive frailty and its associated factors.

METHODS

Cross-sectional survey was conducted among the rural community-dwelling elderly population of West Bengal, India (n = 510), without diagnosed dementia at baseline. An Interview-based questionnaire was administered to obtain information on sociodemographic, physical and psychosocial characteristics. Study participants were categorized as non-cognitive impairment (NCI) and cognitive impairment (CI) by Bangla Adaptation of Mini-Mental State Exam (BMSE ≤ 25) scale, as non-physical frailty (NPF) and physical frailty (PF) using Modified Fried Frailty Phenotype (FP ≥ 3) scale, as robust (NPF + NCI), pre-cognitive frailty (NPF + CI or PF + NCI) and cognitive frailty (PF + CI).

RESULTS

The overall prevalence of cognitive frailty was 21.8%. In multinomial regression analysis, final model indicated that increasing age, being woman, out-of-wedlock, poor education and non-working sociodemographic status had significant association with cognitive frailty. Poor nutritional status, low health-related quality of life and depression are also prone among the cognitively frail participants.

CONCLUSIONS

Present study allows us to understand complementary relationships between sociodemographic, physical, psychosocial characteristics and cognitive frailty. There is a dire need for multidimensional approach for providing appropriate and comprehensive geriatric health care for developing countries like India.

No clear associations between subjective memory concerns and subsequent change in cognitive function: the PATH through life study

The literature on subjective memory concerns (SMC) as a predictor for future cognitive decline is varied. Furthermore, recent research has pointed to additional complexity arising from variability in the experience of SMC themselves (i.e. whether they are remitting or sustained over time). We investigated the associations between SMC and objectively measured cognition in an Australian population-based cohort. Four waves (4-year intervals between waves) of data from 1236 participants (aged 62.4 ± 1.5 years, 53% male) were used. We categorized participants as experiencing SMC, when they indicated that their memory problems might interfere with their day-to-day life and/or they had seen a doctor about their memory. SMC was categorized as "no" reported SMC, "remitting", "new-onset" or "sustained" SMC. Cognitive assessment of immediate and delayed recall, working memory, psychomotor speed, attention and processing speed were assessed using a neuropsychological battery. Eighteen percent of participants were characterised as having SMC: 6% (77) "remitting", 6% (77) "new-onset" and 6% (69) "sustained" SMC. There was no consistent evidence for an association between SMC and subsequent decline in cognition. However, SMC was associated with poorer performance on contemporaneous tasks of attention and processing speed compared to "no" SMC. Asking about SMC may indicate a current decline in cognitive function but, in this sample at least, did not indicate an increased risk of future decline.

Association of Cognitive Performance with Frailty in Older Individuals with Cognitive Complaints

OBJECTIVES

Frailty is a risk factor for poor cognitive performance in older adults. However, few studies have evaluated the association of cognitive performance with frailty in a low- to middle-income country (LMIC). This study aimed to investigate an association between cognitive performance and frailty in older adults with memory complaints in Brazil. Secondarily, we aim to assess an association of cognitive performance with gait speed and grip strength.

DESIGN

Cross-sectional study.

SETTING

Outpatient service from a LMIC.

PARTICIPANTS

Older adults with memory complaints reported by the participants, their proxies, or their physicians.

MEASUREMENTS

Frailty was evaluated using the Cardiovascular Health Study criteria. A neuropsychological battery evaluated memory, attention, language, visuospatial function, executive function. Linear regression analysis with adjustment for age, sex, and education was used. We also evaluated the interaction of education with frailty, grip strength, and gait speed.

RESULTS

Prefrailty was associated with poor performance in the memory domain, as well as slower gait speed was associated with worse performance in memory, attention, language, and executive function. Frailty and grip strength were not associated with cognitive performance. Interactions of education with gait speed were significant for global performance, as well as for attention and visuospatial ability.

CONCLUSION

In elderly patients with memory complaints, prefrailty was associated with poor memory performance. Slowness was associated with poorer performance in some cognitive domains, mainly in participants with low education.

Decreased Resting-State Functional Complexity in Elderly with Subjective Cognitive Decline

Individuals with subjective cognitive decline (SCD) are at high risk of developing preclinical or clinical state of Alzheimer’s disease (AD). Resting state functional magnetic resonance imaging, which can indirectly reflect neuron activities by measuring the blood-oxygen-level-dependent (BOLD) signals, is promising in the early detection of SCD. This study aimed to explore whether the nonlinear complexity of BOLD signals can describe the subtle differences between SCD and normal aging, and uncover the underlying neuropsychological implications of these differences. In particular, we introduce amplitude-aware permutation entropy (AAPE) as the novel measure of brain entropy to characterize the complexity in BOLD signals in each brain region of the Brainnetome atlas. Our results demonstrate that AAPE can reflect the subtle differences between both groups, and the SCD group presented significantly decreased complexities in subregions of the superior temporal gyrus, the inferior parietal lobule, the postcentral gyrus, and the insular gyrus. Moreover, the results further reveal that lower complexity in SCD may correspond to poorer cognitive performance or even subtle cognitive impairment. Our findings demonstrated the effectiveness and sensitiveness of the novel brain entropy measured by AAPE, which may serve as the potential neuroimaging marker for exploring the subtle changes in SCD.

Feasibility randomized controlled trial of a mind-body activity program for older adults with chronic pain and cognitive decline: The virtual "Active Brains" study

BACKGROUND AND OBJECTIVES

Chronic pain (CP) and cognitive decline (CD) are highly co-morbid and debilitating among older adults. We iteratively developed Active Brains-Fitbit (AB-F), a group mind-body activity program aided by a Fitbit that is feasible and associated with improvements in physical, cognitive, and emotional functioning when delivered in person to older adults with CP and CD. We adapted our intervention and methodology for remote delivery to bypass barriers to participation. Here we report on a feasibility randomized controlled trial of the virtual AB-F versus a Health Enhancement Program (HEP) educational control followed by qualitative exit interviews.

RESEARCH DESIGN AND METHODS

Older adults (age ≥ 60) with CP and CD (2 cohorts) completed eight weeks of AB-F (n = 8) or HEP (n = 11). Study procedures were fully remote via live video. Quantitative analyses explored feasibility and acceptability markers and within group improvements in outcomes. Qualitative analyses were primarily deductive using the Framework Method.

RESULTS

AB-F met a-priori set feasibility benchmarks, similar to our in-person pilot. Participation in AB-F was associated with preliminary signals of improvement in multimodal physical function, emotional function (anxiety), cognitive function, pain intensity, and coping (e.g., pain self-efficacy, catastrophizing). Participation in HEP was associated with smaller or negligible improvements. Exit interviews confirmed feasibility and satisfaction with our completely remote interventions and methodology.

DISCUSSION AND IMPLICATIONS

Results provide evidence for the feasibility of our completely remote study, and for initial markers of improvement after AB-F. The results will inform a fully powered remote efficacy trial.

Ultrarapid Inflammation of the Olfactory Bulb After Spinal Cord Injury: Protective Effects of the Granulocyte Colony-Stimulating Factor on Early Neurodegeneration in the Brain

The correlation among olfactory dysfunction, spinal cord injury (SCI), subjective cognitive decline, and neurodegenerative dementia has been established. Impaired olfaction is considered a marker for neurodegeneration. Hence, there is a need to examine if SCI leads to olfactory dysfunction. In this study, the brain tissue of mice with spinal cord hemisection injury was subjected to microarray analysis. The mRNA expression levels of olfactory receptors in the brain began to decline at 8 h post-SCI. SCI promoted neuroinflammation, downregulated the expression of olfactory receptors, decreased the number of neural stem cells (NSCs), and inhibited the production of neurotrophic factors in the olfactory bulbs at 8 h post-SCI. In particular, the SCI group had upregulated mRNA and protein expression levels of glial fibrillary acidic protein (GFAP; a marker of astrocyte reactivation) and pro-inflammatory mediators [IL-1β, IL-6, and Nestin (marker of NSCs)] in the olfactory bulb compared to levels in the sham control group. The mRNA expression levels of olfactory receptors (Olfr1494, Olfr1324, Olfr1241, and Olfr979) and neurotrophic factors [brain-derived neurotrophic factor (BDNF), glial cell-derived neurotrophic factor (GDNF), and nerve growth factor (NGF)] were downregulated in the olfactory bulb of the SCI group mice at 8 h post-SCI. The administration of granulocyte colony-stimulating factor (G-CSF) mitigated these SCI-induced pathological changes in the olfactory bulb at 8 h post-SCI. These results indicate that the olfactory bulb is vulnerable to environmental damage even if the lesion is located at sites distant from the brain, such as the spinal cord. Additionally, SCI initiated pathological processes, including inflammatory response, and impaired neurogenesis, at an early stage. The findings of this study will provide a basis for future studies on pathological mechanisms of early neurodegenerative diseases involving the olfactory bulb and enable early clinical drug intervention.

Subjective Cognitive Decline May Be Associated With Post-operative Delirium in Patients Undergoing Total Hip Replacement: The PNDABLE Study

Objective: Subjective cognitive decline (SCD) is associated with an increased risk of clinical cognitive disorders. Post-operative delirium (POD) is a common complication after total hip replacement. We aimed to investigate the relationship between SCD and POD in patients undergoing total hip replacement. Methods: Our study recruited 214 cognitively intact individuals from the Perioperative Neurocognitive Disorder And Biomarker Lifestyle (PNDABLE) study in the final analysis. SCD was diagnosed with Subjective Cognitive Decline Scale (SCDS), Mini-Mental State Examination (MMSE), and Montreal Cognitive Assessment (MoCA). The incidence of POD was evaluated by using Confusion Assessment Method (CAM), and POD severity was measured by using the Memorial Delirium Assessment Scale (MDAS). Preoperative cerebrospinal fluid (CSF) Aβ40, Aβ42, T-tau, and P-tau levels were measured by enzyme-linked immune-sorbent assay (ELISA). Results: Overall, the incidence of POD was 26.64% (57/214), including 32.43% (36/111) in the SCD group and 20.39% (21/103) in the NC group. With the increase of age, the incidence of POD in all age groups increased (P < 0.05). Logistic regression analysis showed that after adjusting for SCD, Aβ42, Aβ40, P-tau, and T-tau, SCD (OR 2.32, CI 1.18-4.55, P = 0.01) and the increased CSF level of P-tau (OR 1.04, CI 1.01-1.06, P < 0.001) were risk factors for POD, while the level of aβ42 (OR 0.99, CI 0.99-1.00, P < 0.001) was a protective factor for POD. Conclusion: SCD is one of the preoperative risk factors for POD. Clinical Trial Registration: This study was registered at China Clinical Trial Registry (Chictr200033439).

IN VIVO ASSESSMENT OF AMYLOID AND GLUCOSE SIGNATURES IN SUBJECTIVE COGNITIVE DECLINE SUBJECTS

Subjective cognitive decline (SCD), characterized by self-perceived subtle cognitive impairment ahead of the appearance of explicit and measurable cognitive deficits, is regarded as the preclinical manifestation of the pathological change continuum of Alzheimer’s disease (AD). We were committed to exploring the amyloid and glucose metabolic signatures related to imminent brain metabolic changes in SCD subjects. This study included 39 subjects (mean age = 71.9 years; 14 males and 25 females) diagnosed with SCD disease and 39 gender-matched healthy controls (HCs) (mean age = 75.2; 16 males and 23 females) with brain [18F] fluorodeoxyglucose positron emission tomography (PET) images and [18F] florbetapir PET images. The standardized uptake value ratios (SUVRs) of PET images within the regions of interest (ROIs) were calculated. Inter-group SUVR differences were assessed by two-sample [Formula: see text]-testing and receiver operating characteristic curve (ROC) analyses. A generalized linear model (GLM) was employed to evaluate the correlations between amyloid and FDG uptake. Compared with HCs, SCD subjects showed significantly increased amyloid SUVR, as well as significantly increased glucose SUVR in the olfactory, amygdala, thalamus, heschl gyrus, superior and middle temporal gyrus and temporal pole (all [Formula: see text]). The amyloid SUVR of thalamus was found to have a better ROC result (area under the curve (AUC): 0.77, 95% confidence interval (CI): 0.66–0.86) in the HC group, as was the case with the glucose SUVR of the middle temporal gyrus (AUC: 0.83, 95% CI: 0.73–0.91). There were significant positive correlations between amyloid and glucose SUVRs ([Formula: see text]). The amyloid SUVR of the thalamus showed a significantly better main effect (odd ratio [Formula: see text] 2.91, 95% CI: 1.44–6.7, [Formula: see text]), and the glucose SUVR of the heschl gyrus indicated an enhanced main effect (odd ratio [Formula: see text] 5.08, 95% CI: 1.86–18.15, [Formula: see text]). SCD subjects demonstrated significant amyloid accumulation and glucose hypermetabolism in specific brain regions, and amyloid pathology overlapped with regions of glucose abnormality. These findings may advance the understanding of imminent pathological changes in the SCD stage and help to provide clinical guidelines for interventional management.

Incorporating a Usual Care Comparator into a Study of Meditation and Music Listening for Older Adults with Subjective Cognitive Decline: A Randomized Feasibility Trial

BACKGROUND

Recent studies suggest meditation and music listening (ML) may improve cognitive and psychosocial outcomes in adults with subjective cognitive decline (SCD). However, lack of a usual care group has limited conclusions.

OBJECTIVE

To assess the: 1) feasibility of incorporating an enhanced usual care (EUC) comparator in a trial of Kirtan Kriya meditation (KK) and ML for adults experiencing SCD; and 2) preliminary effects of active treatment (KK/ML) versus an EUC program.

METHODS

Forty participants with SCD were randomized 1:1:2 to a 12-week KK, ML, or EUC program. KK and ML participants were asked to practice 12 minutes/day; EUC participants were given a comprehensive educational packet regarding healthy aging and strategies for improving/maintaining brain health and asked to record any activities or strategies used. Feasibility was assessed using measures of retention, adherence, treatment expectancies, and participant satisfaction, as well as information from exit questionnaires and daily practice/activity logs. Cognitive functioning, stress, mood, sleep-quality, and health-related quality of life (QOL) were measured pre- and post-intervention using well-validated instruments.

RESULTS

Thirty-two participants (80%) completed the 3-month study, with retention highest in the EUC group (p < 0.05). Active treatment participants averaged 6.0±0.4 practice sessions/week, and EUC participants, 7.5±0.6 brain health activities/week. Treatment expectancies were similar across groups. EUC participants indicated high satisfaction with the program and study. Despite limited study power, the active treatment group showed significantly greater gains in subjective memory functioning (ps≤0.025) and nonsignificant improvements in cognitive performance (TMT-B), perceived stress, QOL, and mood (ps≤0.08) compared to the EUC group.

CONCLUSION

Findings of this pilot feasibility trial suggest incorporation of an EUC program is feasible, and that participation in a simple 12-week relaxation program may be helpful for adults with SCD versus engagement in an EUC program.

Altered Regional Cerebral Blood Flow and Brain Function Across the Alzheimer's Disease Spectrum: A Potential Biomarker

Objective: To investigate variation in the characteristics of regional cerebral blood flow (rCBF), brain activity, and intrinsic functional connectivity (FC) across the Alzheimer's disease spectrum (ADS).

Methods: The study recruited 20 individuals in each of the following categories: Alzheimer's disease (AD), mild cognitive impairment (MCI), subjective cognitive decline (SCD), and healthy control (HC). All participants completed the 3.0T resting-state functional MRI (rs-fMRI) and arterial spin labeling scans in addition to neuropsychological tests. Additionally, the normalized CBF, regional homogeneity (ReHo), and amplitude of low-frequency fluctuation (ALFF) of individual subjects were compared in the ADS. Moreover, the changes in intrinsic FC were investigated across the ADS using the abnormal rCBF regions as seeds and behavioral correlations. Finally, a support-vector classifier model of machine learning was used to distinguish individuals with ADS from HC.

Results: Compared to the HC subjects, patients with AD showed the poorest level of rCBF in the left precuneus (LPCUN) and right middle frontal gyrus (RMFG) among all participants. In addition, there was a significant decrease in the ALFF in the bilateral posterior cingulate cortex (PCC) and ReHo in the right PCC. Moreover, RMFG- and LPCUN-based FC analysis revealed that the altered FCs were primarily located in the posterior brain regions. Finally, a combination of altered rCBF, ALFF, and ReHo in posterior cingulate cortex/precuneus (PCC/PCUN) showed a better ability to differentiate ADS from HC, AD from SCD and MCI, but not MCI from SCD.

Conclusions: The study demonstrated the significance of an altered rCBF and brain activity in the early stages of ADS. These findings, therefore, present a potential diagnostic neuroimaging-based biomarker in ADS. Additionally, the study provides a better understanding of the pathophysiology of AD.

Salivary cortisol is associated with cognitive changes in patients with fibromyalgia

Fibromyalgia (FM) is a stress-related chronic pain disorder with common cognitive complaints. This study characterized cognitive dysfunction in patients with FM and explored whether these changes are linked to altered cortisol levels. Consecutive 44 patients with FM and 48 healthy controls were enrolled for the assessments of subjective and objective cognitive functions and diurnal levels of salivary cortisol (sampled at awakening, 30 min after awakening, 3 pm, and bedtime). All measurements were compared between the groups and evaluated for clinical correlation. The FM group had more subjective cognitive complaints and performed poorer in objective cognitive testing in memory (delayed recall in Chinese Version Verbal Learning Test and Taylor Complex Figure Test), language (Boston Naming Test), and executive domains (Wisconsin Card Sorting Test) after adjustments for education. The diurnal cortisol levels of patients with FM tended to be lower, especially at 30 min after awakening and bedtime. Moreover, moderate positive correlations existed between the Chinese Version Verbal Learning Test, Boston Naming Test and the morning cortisol levels within the FM group. We suggested the altered cognitive function in FM may be linked to stress maladaptation. Future studies are warranted to elucidate whether stress management improves cognitive performance in patients with FM.

Slow Gait, Subjective Cognitive Decline and Motoric Cognitive RISK Syndrome: Prevalence and Associated Factors in Community Dwelling Older Adults

BACKGROUND

Motoric Cognitive Risk Syndrome (MCR), slow gait speed (SG) and subjective cognitive decline (SCD) are known to be harbingers of dementia. MCR is known to be associated with a 3-fold increased risk of future dementia, while SG can precede cognitive impairment.

OBJECTIVE

We aim to determine the prevalence and demographics of MCR, slow gait alone (SG-A) and subjective cognitive decline alone (SCD-A) in community-dwelling older adults and association with physical, functional, cognition and psychosocial factors.

METHODS

A total of 509 participants were classified into four groups according to presence of SG and/or SCD. Multinomial logistic regression was used to identify the factors associated with SG-A, SCD-A and MCR.

RESULTS

The prevalence of MCR was 13.6%, SG-A 13.0% and SCD-A 35.0%. Prevalence of MCR doubled every decade in females with 27.7% of female ≥ 80 years old had MCR. Almost 4 in 10 had no SG or SCD (SG+SCD negative). MCR and SG-A groups were significantly older, had higher body mass index (BMI), lower education, lower global cognition scores especially in non-memory domains, higher prevalence of low grip strength and lower short physical performance battery scores than those with SCD-A and SG+SCD negative. In addition, the SG-A group had significantly higher prevalence of multi-morbidity and diabetes. The prevalence of pain, depression, frailty, social isolation and activity of daily living impairment were significantly higher in MCR. The global cognitive and functional scores for those with SCD-A were comparable to the SG+SCD negative group. The Malay ethnic group had the lowest prevalence of SCD but highest prevalence of SG. After adjusting for confounding factors, age, BMI, frailty status, instrumental activity of daily living, depression and pain remained significantly associated with MCR. For SG-A, age, BMI, education and number of chronic diseases remained significant.

CONCLUSION

Both MCR and SG-A are associated with global cognitive decline especially in the non-memory domains and lower functional scores. Gait speed is a good predictor of negative outcomes and should be considered as the 'sixth' vital sign. Long term prospective studies are needed to evaluate: i) the conversion to dementia in different ethnic groups and ii) effect of targeted physical and / or dual task exercise on delaying the conversion to dementia and / or improvement in physical measures and reduction of disability.

Association between the brief inventory of neurocognitive impairment (BINI) and objective cognitive testing among persons with opioid use disorders in drug treatment

The current study examined the association between subjective cognitive dysfunction and objective test performance in persons enrolled in drug treatment and stabilized on methadone maintenance therapy (MMT). A total of 177 participants completed the self-reported brief inventory of neurocognitive impairment (BINI) and NIH Toolbox test battery. In participants with neurocognitive dysfunction, scores on all BINI subscales were negatively associated with objective performance on the NIH Toolbox (BINI Global r = -0.26, p = 0.01; BINI Subscales ranging -0.22 to -0.32, all p's < 0.03). Using cutoff scores, results showed participants who scored above the cutoff on the BINI Learning subscale demonstrated significant evidence of objective neurocognitive dysfunction on the NIH Toolbox (65% vs. 35%; χ² = 6.57, p = 0.02), suggesting possible clinical utility. Future studies are needed to determine the feasibility of using the BINI to inform the accommodation of patients with specific neurocognitive profiles to optimize treatment outcomes.