Objective features of subjective cognitive decline in a United States national database

Identifying older adults at risk for dementia based on smartphone data obtained during a wayfinding task in the real world

Alzheimer's disease (AD), as the most common form of dementia and leading cause for disability and death in old age, represents a major burden to healthcare systems worldwide. For the development of disease-modifying interventions and treatments, the detection of cognitive changes at the earliest disease stages is crucial. Recent advancements in mobile consumer technologies provide new opportunities to collect multi-dimensional data in real-life settings to identify and monitor at-risk individuals. Based on evidence showing that deficits in spatial navigation are a common hallmark of dementia, we assessed whether a memory clinic sample of patients with subjective cognitive decline (SCD) who still scored normally on neuropsychological assessments show differences in smartphone-assisted wayfinding behavior compared with cognitively healthy older and younger adults. Guided by a mobile application, participants had to find locations along a short route on the medical campus of the Magdeburg university. We show that performance measures that were extracted from GPS and user input data distinguish between the groups. In particular, the number of orientation stops was predictive of the SCD status in older participants. Our data suggest that subtle cognitive changes in patients with SCD, whose risk to develop dementia in the future is elevated, can be inferred from smartphone data, collected during a brief wayfinding task in the real world.

Subjective cognitive decline and objective cognitive performance in older adults: A systematic review of longitudinal and cross-sectional studies

Older adults with subjective cognitive decline (SCD) have a higher risk of developing future cognitive decline than those without SCD. However, the association between SCD and objective cognitive performance remains unclear. This PRISMA 2020-compliant systematic review aims to provide a qualitative assessment of the longitudinal and cross-sectional relationship between SCD and objective cognitive performance in different cognitive domains, in neuropsychologically healthy, community-dwelling older adults (average age of 55 or older). To identify pertinent studies, a comprehensive search was conducted from seven databases. The National Heart, Lung and Blood Institute Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies was used to assess the quality of included studies. Inclusion criteria were met by 167 studies, which were full-text and published between 1 January 1982 and 16 May 2023 (inclusive) in the languages of English, French, or Spanish and presenting data on objective cognitive performance in older adults with SCD. Overall, we found that SCD was associated with poorer objective cognitive performance on measures of global cognition and memory longitudinally compared to non-SCD status, but this association was inconsistent in cross-sectional studies. This association became stronger with the use of continuous measures of SCD as opposed to dichotomous measures. Additionally, results highlight the known lack of consistency in SCD assessment among studies and comparatively small number of longitudinal studies in SCD research.

The McCusker Subjective Cognitive Impairment Inventory (McSCI): a novel measure of perceived cognitive decline

BACKGROUND

Subjective cognitive decline (SCD), i.e. self/other-reported concerns on one's cognitive functioning without objective evidence of significant decline, is an indicator of dementia risk. There is little consensus on reliability and validity of the available SCD measures. Therefore, introducing a novel and psychometrically sound measure of SCD is timely.

OBJECTIVE

The psychometric properties of a new SCD measure, the McCusker Subjective Cognitive Impairment Inventory-Self-Report (McSCI-S), are reported.

METHODS

Through review of previously published measures as well as our clinical and research data on people with SCD, we developed a 46-item self-report questionnaire to assess concerns on six cognitive domains, namely, memory, language, orientation, attention and concentration, visuoconstruction abilities and executive function. The McSCI-S was examined in a cohort of 526 participants using factor analysis, item response theory analysis and receiver operating characteristic (ROC) curve.

RESULTS

A unidimensional model provided acceptable fit (CFI = 0.94, TLI = 0.94, RMSEA [90% CI] = 0.052 [.049, 0.055], WRMR = 1.45). The McSCI-S internal consistency was excellent (.96). A cut-off score of ≥24 is proposed to identify participants with SCDs. Higher McSCI-S scores were associated with poorer general cognition, episodic verbal memory, executive function and greater memory complaints and depressive scores (P < .001), controlling for age, sex and education.

CONCLUSIONS

Excellent reliability and construct validity suggest the McSCI-S estimates SCDs with acceptable accuracy while capturing self-reported concerns for various cognitive domains. The psychometric analysis indicated that this measure can be used in cohort studies as well as on individual, clinical settings to assess SCDs.

Relationship Between Excessive Daytime Sleepiness and Caudate Nucleus Volume in Patients with Subjective Cognitive Decline: A Study from the SILCODE Using the Volbrain

Background

Excessive daytime sleepiness (EDS) and caudate nucleus volume alterations have been linked to Alzheimer's disease (AD), but their relationship remains unclear under the context of subjective cognitive decline (SCD).

Objective

This study aimed to investigate the relationship between EDS and caudate nucleus volume in patients with SCD.

Methods

The volume of entire brain was measured in 170 patients with SCD, including 37 patients with EDS and 133 non-EDS, from the Sino Longitudinal Study on Cognitive Decline (SILCODE). Participants underwent a comprehensive assessment battery, including neuropsychological and clinical evaluations, blood tests, genetic analysis for APOE ɛ4, and structural MRI scans analyzed using the fully automated segmentation tool, volBrain.

Results

Patients with EDS had significantly increased volume in the total and left caudate nucleus compared to non-EDS. The most significant cognitive behavioral factor associated with caudate nucleus volume in the EDS was the Auditory Verbal Learning Test-recognition.

Conclusions

These findings suggest that EDS may be associated with alterations in caudate nucleus volume, particularly in the left hemisphere, in the context of SCD. Further research is necessary to understand the underlying mechanisms of this relationship and its implications for clinical management.

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.

Prenatal Exposure to the 1944-45 Dutch Famine and Risk for Dementia up to Age 75: An Analysis of Primary Care Data

BACKGROUND

A poor prenatal environment adversely affects brain development. Studies investigating long-term consequences of prenatal exposure to the 1944-45 Dutch famine have shown that those exposed to famine in early gestation had poorer selective attention, smaller brain volumes, poorer brain perfusion, older appearing brains, and increased reporting of cognitive problems, all indicative of increased dementia risk.

OBJECTIVE

In the current population-based study, we investigated whether dementia incidence up to age 75 was higher among individuals who had been prenatally exposed to famine.

METHODS

We included men (n=6,714) and women (n=7,051) from the Nivel Primary Care Database who had been born in seven cities affected by the Dutch famine. We used Cox regression to compare dementia incidence among individuals exposed to famine during late (1,231), mid (1,083), or early gestation (601) with those unexposed (born before or conceived after the famine).

RESULTS

We did not observe differences in dementia incidence for those exposed to famine in mid or early gestation compared to those unexposed. Men and women exposed to famine in late gestation had significantly lower dementia rates compared to unexposed individuals (HR 0.52 (95%CI 0.30-0.89)). Sex-specific analyses showed a lower dementia rate in women exposed to famine in late gestation (HR 0.39 (95%CI 0.17-0.86)) but not in men (HR 0.68 (95%CI 0.33-1.41)).

CONCLUSION

Although prenatal exposure to the Dutch famine has previously been associated with measures of accelerated brain aging, the present population-based study did not show increased dementia incidence up to age 75 in those exposed to famine during gestation.

Greater subjective cognitive decline severity is associated with worse memory performance and lower entorhinal cerebral blood flow in healthy older adults

OBJECTIVE

Subjective cognitive decline (SCD) is a potential early risk marker for Alzheimer's disease (AD), but its utility may vary across individuals. We investigated the relationship of SCD severity with memory function and cerebral blood flow (CBF) in areas of the middle temporal lobe (MTL) in a cognitively normal and overall healthy sample of older adults. Exploratory analyses examined if the association of SCD severity with memory and MTL CBF was different in those with lower and higher cardiovascular disease (CVD) risk status.

METHODS

Fifty-two community-dwelling older adults underwent magnetic resonance imaging, neuropsychological testing, and were administered the Everyday Cognition Scale (ECog) to measure SCD. Regression models investigated whether ECog scores were associated with memory performance and MTL CBF, followed by similar exploratory regressions stratified by CVD risk status (i.e., lower vs higher stroke risk).

RESULTS

Higher ECog scores were associated with lower objective memory performance and lower entorhinal cortex CBF after adjusting for demographics and mood. In exploratory stratified analyses, these associations remained significant in the higher stroke risk group only.

CONCLUSIONS

Our preliminary findings suggest that SCD severity is associated with cognition and brain markers of preclinical AD in otherwise healthy older adults with overall low CVD burden and that this relationship may be stronger for individuals with higher stroke risk, although larger studies with more diverse samples are needed to confirm these findings. Our results shed light on individual characteristics that may increase the utility of SCD as an early risk marker of cognitive decline.

Relevance of Minor Neuropsychological Deficits in Patients With Subjective Cognitive Decline

BACKGROUND AND OBJECTIVES

To determine the relevance of minor neuropsychological deficits (MNPD) in patients with subjective cognitive decline (SCD) with regard to CSF levels of Alzheimer disease (AD) biomarkers, cognitive decline, and clinical progression to mild cognitive impairment (MCI).

METHODS

This study included patients with clinical SCD and SCD-free, healthy control (HC) participants with available baseline CSF and/or longitudinal cognitive data from the observational DZNE Longitudinal Cognitive Impairment and Dementia study. We defined MNPD as a performance of at least 0.5SD below the mean on a demographically adjusted total score derived from the Consortium to Establish a Registry for Alzheimer's Disease neuropsychological assessment battery. We compared SCD patients with MNPD and those without MNPD with regard to CSF amyloid-β (Aβ)42/Aβ40, phosphorylated tau (p-tau181), total tau and Aβ42/p-tau181 levels, longitudinal cognitive composite trajectories, and risk of clinical progression to incident MCI (follow-up M ± SD: 40.6 ± 23.7 months). In addition, we explored group differences between SCD and HC in those without MNPD.

RESULTS

In our sample (N = 672, mean age: 70.7 ± 5.9 years, 50% female), SCD patients with MNPD (n = 55, 12.5% of SCD group) showed significantly more abnormal CSF biomarker levels, increased cognitive decline, and a higher risk of progression to incident MCI (HR: 4.07, 95% CI 2.46-6.74) compared with SCD patients without MNPD (n = 384). MNPD had a positive predictive value of 57.0% (95% CI 38.5-75.4) and a negative predictive value of 86.0% (95% CI 81.9-90.1) for the progression of SCD to MCI within 3 years. SCD patients without MNPD showed increased cognitive decline and a higher risk of incident MCI compared with HC participants without MNPD (n = 215; HR: 4.09, 95% CI 2.07-8.09), while AD biomarker levels did not differ significantly between these groups.

DISCUSSION

Our results suggest that MNPD are a risk factor for AD-related clinical progression in cognitively normal patients seeking medical counseling because of SCD. As such, the assessment of MNPD could be useful for individual clinical prediction and for AD risk stratification in clinical trials. However, SCD remains a risk factor for future cognitive decline even in the absence of MNPD.

Prevalence and risk factors for subjective cognitive decline and the correlation with objective cognition among community-dwelling older adults in China: Results from the Hubei memory and aging cohort study

INTRODUCTION

The prevalence and risk factors for subjective cognitive decline (SCD) and its correlation with objective cognition decline (OCD) among community-dwelling older adults is inconsistent.

METHODS

Older adults underwent neuropsychological and clinical evaluations to reach a consensus on diagnoses.

RESULTS

This study included 7486 adults without mild cognitive impairment and dementia (mean age: 71.35 years [standard deviation = 5.40]). The sex-, age-, and residence-adjusted SCD prevalence was 58.33% overall (95% confidence interval: 58.29% to 58.37%), with higher rates of 61.25% and 59.87% in rural and female subgroups, respectively. SCD global and OCD language, SCD memory and OCD global, SCD and OCD memory, and SCD and OCD language were negatively correlated in fully adjusted models. Seven health and lifestyle factors were associated with an increased risk for SCD.

DISCUSSION

SCD affected 58.33% of older adults and may indicate concurrent OCD, which should prompt the initiation of preventative intervention for dementia.

HIGHLIGHTS

SCD affects 58.33% of older adults in China. SCD may indicate concurrent objective cognitive decline. Difficulty finding words and memory impairments may indicate a risk for AD. The presence of SCD may prompt preventative treatment initiation of MCI or dementia. Social network factors may be initial targets for the early prevention of SCD.

Neurocognitive Characteristics of Subjective Cognitive Decline and Its Association with Objective Cognition, Negative Emotion, and Sleep Quality in Chinese Elderly

Background and Purpose

Subjective cognitive decline (SCD) is recognized as a preclinical indicator of Alzheimer's disease (AD), and this stage provides a valuable time window for ultra-early intervention in AD. The aim of this study was to investigate the neurocognitive characteristics of SCD and its correlation with objective cognition, negative emotion and sleep quality in Chinese elderly.

Methods

A total of 1200 volunteers aged 60 and older underwent Brief Elderly Cognitive Screening Inventory, Quick Cognitive Screening Scale for the Elderly, Generalized Anxiety Disorder-7, Patient Health Questionnaire-9, Pittsburgh Sleep Quality Index and Core Neuropsychological Test. According to the examination results, the participants were divided into healthy control (HC) and SCD groups. The neurocognitive function of SCD and its relationship with objective cognition, negative emotion and sleep quality were analyzed.

Results

Compared with the HC group, the SCD group had similar global cognitive function but slightly impaired neurocognitive function. After adjusting for confounding factors such as age, sex, marriage, education and chronic disease, neurocognitive function (Picture-Symbol Matching: OR=0.167, 95% CI: 0.105-0.266; Word Stem Completion: OR =0.260, 95% CI: 0.131-0.514; Trail Making Test: OR=0.315, 95% CI: 0.178-0.560; Picture Recall: OR =0.278, 95% CI: 0.122-0.636), negative emotion (sub-depressive symptoms: OR=2.287, 95% CI: 1.483-3.527; sub-anxiety symptoms: OR=1.663, 95% CI: 1.079-2.563), and poor sleep quality (OR=2.138, 95% CI: 1.571-2.909) were significantly correlated with the occurrence of SCD.

Conclusion

The study illustrates that SCD is closely related to objective cognition, negative emotion and sleep quality. Clinical evaluation and follow-up of SCD should fully account for these factors.

The "when" matters: Evidence from memory markers in the clinical continuum of Alzheimer's disease

OBJECTIVE

Cognitive assessment able to detect impairments in the early neuropathological stages of Alzheimer's disease (AD) is urgently needed. The visual short-term memory binding task (VSTMBT) and the Free and Cued Selective Reminding Test (FCSRT) have been recommended by the neurodegenerative disease working group as promising tests to aid in the early detection of AD. In this study, we investigated their complementary value across the clinical stages of the AD continuum.

METHOD

One hundred and seventeen older adults with subjective cognitive complaint (SCC), 79 with mild cognitive impairment (MCI), 31 patients with AD dementia (ADD), and 37 cognitively unimpaired (CU) subjects, underwent assessment with the VSTMBT and the picture version of the Spanish FCSRT.

RESULTS

After controlling for multiple comparisons, significant differences were found across groups. The VSTMBT was the only test that "marginally" differentiated between CU and SCC (d = 0.47, p = .052). Moreover, whereas the FCSRT showed a gradient (CU = SCC) > MCI > ADD, the VSTMBT gradient was CU > SCC > (MCI = ADD) suggesting that conjunctive binding deficits assessed by the latter may be sensitive to the very early stages of the disease.

CONCLUSIONS

Our results suggest that the VSTMBT and the FCSRT are sensitive to the clinical continuum of AD. Whereas the former detects changes in the early prodromal stages, the latter is more sensitive to the advanced prodromal stages of AD. These novel tests can aid in the early detection, monitor disease progression and response to treatment, and thus support drug development programs. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

The impact of technology-based compensatory behaviors on subjective cognitive decline in older adults with a family history of dementia

The current study examined whether greater use of technology to help with daily tasks is associated with less subjective cognitive decline (SCD), especially in individuals with a family history of Alzheimer's disease (AD). Individuals over the age of 50 (n = 102; age range 50-85) completed surveys about their digital and analog approaches to daily tasks, physical activity, and SCD. Participants with and without family histories of AD were matched on age, education, sex, and family history of AD using the R package MatchIt. There was no main effect of technology-based behavioral strategies on SCD (p = 0.259). However, a family history of AD moderated the association between technology use and SCD even when controlling for another protective lifestyle factor, physical activity. In individuals with a family history of AD, more reliance on technology-based behavioral strategies was associated with less SCD (p = 0.018), but this relationship was not significant in individuals without family history of AD (p = 0.511). Our findings suggest that technology-based behavioral strategies are associated with less SCD in individuals with a family history of AD, independent of another protective lifestyle factor. Future recommendations provided by healthcare providers to address SCD in cognitively unimpaired older adults might include focusing on technological assistance.

Exposure to the Dutch Famine in Early Gestation and Cognitive Function and Decline in Older Age

People exposed to the 1944-1945 Dutch famine in early gestation performed worse on a selective attention task at age 58 and reported more cognitive problems at age 72. We here hypothesized that undernutrition in early gestation is associated with poorer cognitive functioning in older age and a higher rate of cognitive decline. We tested this hypothesis in the Dutch famine birth cohort in men and women combined and separately. We assessed cognitive function using a Stroop-like, trail-making and 15-word task (at ages 68 and 74) and the Montreal cognitive assessment as well as self-perceived cognitive problems (at age 74) in 73 men (n = 34) and women (n = 39). We compared cognitive function and decline (change in cognitive function between age 68 and 74) between those exposed in early gestation and those not exposed (born before or conceived after the famine). Although in both men and women cognitive function declined from age 68 to 74, cognitive task scores and the rate of decline did not differ between those exposed or unexposed to famine. At age 74, men exposed to famine in early gestation more often reported cognitive problems, although this was not statistically different from unexposed men (OR 3.1 [95%CI 0.7 to 13.0]). We did not find evidence of increased cognitive decline after prenatal undernutrition. Selective participation and mortality may have hampered our ability to detect potential true effects. The self-perceived cognitive problems among men who had been exposed to famine in early gestation might be an indication of future dementia risk.

Tau levels are higher in objective subtle cognitive decline but not subjective memory complaint

BACKGROUND

The 2018 NIA-AA Alzheimer's Disease (AD) Research Framework states that subtle cognitive decline in cognitively unimpaired individuals can be measured by subjective reports or evidence of objective decline on neuropsychological measures. Both subjective memory complaint (SMC) and objective subtle cognitive decline (Obj-SCD) have been shown to be associated with future cognitive decline and AD biomarkers. We examined whether there are differences in tau PET levels between (a) SMC- vs. SMC+ participants, (b) Obj-SCD- vs. Obj-SCD+ participants, and (c) participants with overlapping vs. discrepant SMC and Obj-SCD classifications.

METHODS

Cognitively unimpaired participants from the Alzheimer's Disease Neuroimaging Initiative (ADNI; n = 236) were classified at baseline as positive or negative for SMC (SMC- n = 77; SMC+ n = 159) based on the first 12 items of the Cognitive Change Index and/or classified as positive or negative for Obj-SCD (Obj-SCD- n = 173; Obj-SCD+ n = 63) based on previously defined neuropsychological criteria. Analyses of covariance, adjusting for age, sex, APOE ε4 carrier status, and pulse pressure, examined the group differences in tau PET (AV-1451) using a composite standardized uptake variable ratio (SUVR) for regions consistent with Braak stage III/IV. The chi-squared tests examined the tau positivity rates across the groups.

RESULTS

Obj-SCD+ participants had higher tau continuous SUVR levels (p = .035, ηp2 = .019) and higher rates of tau positivity (15.8% Obj-SCD- vs. 30.2% Obj-SCD+) than Obj-SCD- participants. Neither tau levels (p = .381, ηp2 = .003) nor rates of tau positivity (18.2% SMC- and 20.1% SMC+) differed between the SMC groups. There was very little agreement between SMC and Obj-SCD classifications (42%; κ = 0.008, p = .862). Participants who were Obj-SCD+ without SMC had the highest tau PET levels and differed from participants who were SMC+ without Obj-SCD (p = .022). Tau levels in participants with both SMC and Obj-SCD did not differ from those with only Obj-SCD (p = .216). Tau positivity rates across the SMC-/Obj-SCD-, SMC+/Obj-SCD-, SMC-/Obj-SCD+, and SMC+/Obj-SCD+ groups were 10.5%, 18.1%, 40.0%, and 25.6%, respectively.

CONCLUSION

Participants with Obj-SCD had a greater tau PET burden than those without Obj-SCD, but SMC was not associated with higher tau levels. The combination of SMC and Obj-SCD did not have higher tau levels than Obj-SCD alone. Findings add to the evidence that the Obj-SCD classification is associated with AD biomarkers and faster cognitive decline in ADNI participants, but further work is needed to validate this approach in more representative/diverse cohorts.

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.

The Influence of Amyloid Burden on Cognitive Decline over 2 years in Older Adults with Subjective Cognitive Decline: A Prospective Cohort Study

BACKGROUND

Subjective cognitive decline (SCD) is a self-perceived cognitive worsening without objective cognitive impairment. Due to its heterogeneity and potential risk of Alzheimer's disease (AD), baseline biomarkers to predict progression are clinically important. In the present study, cognitive trajectories during a 24-month period were compared between amyloid-positive SCD (A+SCD) and amyloid-negative SCD (A-SCD) subjects, and biomarkers associated with memory decline were investigated.

METHODS

Data from a prospective cohort study in Korea between 2016 and 2019 were analyzed. SCD subjects ≥50 years of age were eligible. All participants underwent neuropsychological tests, brain magnetic resonance imaging, and florbetaben positron emission tomography scans. Amyloid burden and regional volumes were measured. Cognitive changes corrected for age were compared between A+SCD and A-SCD groups. Biomarkers associated with memory decline were assessed.

RESULTS

Forty-seven SCD subjects (69.9 ± 6.7 years, mini-mental state examination (MMSE) score 27.5) were enrolled, and 31 completed at least 1 annual follow-up (mean follow-up: 24.7 months). Baseline characteristics except age, hippocampal atrophy, and white matter hyperintensities were similar between A+SCDs (n = 12, 25.6%) and A-SCDs (n = 35). A+SCD subjects showed greater decline in the verbal memory function compared with the A-SCD subjects after adjustment for age. MMSE scores decreased more in the A+SCD (1.1 in the A+SCD; 0.55 in the A-SCD), although it was not statistically significant. Amyloid burden and baseline memory score were associated with memory decline.

CONCLUSIONS

Within SCD, A+SCD subjects showed faster memory decline compared with the A-SCD subjects and amyloid burden might be associated with future memory decline in SCD.

Prenatal exposure to the Dutch famine is associated with more self-perceived cognitive problems at 72 years of age

Background

Undernutrition during critical periods of neurodevelopment can hinder the developing brain with lasting negative consequences for brain size, structure and function. In this study, we describe self-perceived cognitive problems of men and women who were born around the time of the Dutch famine of 1944–45.

Methods

We compared self-perceived cognitive problems between men and women who had been exposed to the 1944–45 Dutch famine in late, mid or early gestation and those who were born before or conceived after the famine (and had thus not been exposed prenatally). We included 595 participants aged 71–74 years.

Results

Women who had been exposed to famine in late gestation more often reported cognitive problems compared to those who had not been exposed (OR 2.2 [95% CI 1.1–4.4]), whereas for men, this was the case for those exposed in early gestation (OR 2.3 [0.9–5.5]). Furthermore, men and women exposed in early gestation more often reported consulting a healthcare practitioner for cognitive problems in the past 12 months (OR 3.2 [1.3–8.1]). Especially men exposed in early gestation reported having consulted a healthcare practitioner more often than unexposed men (OR 4.4 [1.2–16.0]).

Conclusions

These findings suggest that prenatal undernutrition does not only have lasting effects on brain size, but also on its function, with more self-perceived cognitive problems at older age, which also require more medical attention. Also, the effects of undernutrition depend on sex and its timing during gestation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-02820-2.

Validation of a modified Chinese version of Mini-Addenbrooke's Cognitive Examination for detecting mild cognitive impairment

BACKGROUND

For detecting mild cognitive impairment (MCI), brief cognitive screening tools are increasingly required for the advantage of time saving and no need for special equipment or trained raters. We aimed to develop a modified Chinese version of Mini-Addenbrooke's Cognitive Examination (C-MACE) and further evaluate its validation in detecting MCI.

METHODS

A total of 716 individuals aged from 50 to 90 years old were recruited, including 431 cognitively normal controls (NC) and 285 individuals with MCI. The effect size of Cramer's V was used to explore which items in the Chinese version of Addenbrooke's Cognitive Examination-III (ACE-III-CV) best associated with MCI and to form the C-MACE. Receiver operating characteristic (ROC) analyses were carried out to explore the ability of C-MACE, ACE-III-CV, Chinese version of Montreal Cognitive Assessment-Basic (MoCA-BC), and Mini-Mental State Examination (MMSE) in discriminating MCI from NC.

RESULTS

Five items with greatest effect sizes of Cramer's V were selected from ACE-III-CV to form the C-MACE: Memory Immediate Recall, Memory Delayed Recall, Memory Recognition, Verbal Fluency Animal and Language Naming. With a total score of 38, the C-MACE had a satisfactory classification accuracy in detecting MCI (area under the ROC curve, AUC = 0.892), superior to MMSE (AUC = 0.782) and comparable to ACE-III-CV (AUC = 0.901) and MoCA-BC (AUC = 0.916). In the subgroup of Age > 70 years, Education ≤ 12 years, the C-MACE got a highest classification accuracy (AUC = 0.958) for detecting MCI.

CONCLUSION

In the Chinese-speaking population, C-MACE derived from ACE-III-CV may identify MCI with a good classification accuracy, especially in aged people 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.

Education, APOE ε4, and Cognition in Individuals with Subjective Cognitive Decline with Worry in the SILCODE Study

BACKGROUND

Education could offer a protective effect on cognition in individuals with Subjective Cognitive Decline (SCD), which is considered to be the early stage of Alzheimer's Disease (AD). However, the effect of education on cognition in SCD individuals with SCD-plus features is not clear.

OBJECTIVE

The aim of the study was to explore the effect of education on cognition in SCD individuals with SCD-plus features.

METHODS

A total of 234 individuals with SCD were included from the Sino Longitudinal Study on Cognitive Decline (SILCODE). Cognition was assessed across 4 domains (memory, executive, language, and general cognitive functions). Multiple linear regression models were constructed to examine the effect of education on cognitive scores in individuals without worry (n=91) and with worry (n=143). Furthermore, we assessed differences in effects between APOE ε4 noncarriers and APOE ε4 carriers in both groups.

RESULTS

Multiple linear regression analysis showed a positive effect of education on memory, executive, and language cognition in individuals without worry and all cognitive domains in individuals with worry. Furthermore, we found a positive effect of education on executive cognition in APOE ε4 noncarriers without worry and language and general cognition in APOE ε4 carriers without worry. Meanwhile, education had a positive effect on all cognitive domains in APOE ε4 noncarriers with worry and executive, language, and general cognition in APOE ε4 carriers with worry.

CONCLUSION

This study indicates that education has the potential to delay or reduce cognitive decline in SCD individuals with SCD-plus features.

Women Exhibit Lower Global Left Frontal Cortex Connectivity Among Cognitively Unimpaired Elderly Individuals: A Pilot Study from SILCODE

BACKGROUND

Mounting evidence suggests that sex differences exist in cognitive reserve (CR) for cognitively unimpaired (CU) elderly individuals. Global left frontal connectivity (gLFC connectivity) is a reliable neural substrate of CR.

OBJECTIVE

The purpose of this study was to explore sex differences in gLFC connectivity among CU elderly individuals.

METHODS

One hundred thirteen normal controls (NCs) (women = 66) and 132 individuals with subjective cognitive decline (SCD) (women = 92) were recruited from the Sino Longitudinal Study on Cognitive Decline (SILCODE) (data 1). Among them, 88 subjects underwent amyloid-β (Aβ) imaging, including 32 Aβ+ and 56 Aβ-subjects. Forty-six subjects underwent another rs-fMRI examination (data 2) to validate the repeatability of the calculation of gLFC connectivity, which was determined through seed-based functional connectivity between the LFC and voxels throughout the whole brain. Independent-sample t-tests were used to evaluate the sex differences in gLFC connectivity across different subgroups (NC versus SCD, Aβ+ versus Aβ-). Partial correlation analysis was used to calculate the correlations between gLFC connectivity and cognitive assessments.

RESULTS

Women exhibited lower gLFC connectivity in both the NC (p = 0.001) and SCD (p = 0.020) subgroups than men. Women also exhibited lower gLFC connectivity in both the Aβ-(p = 0.006) and Aβ+ (p = 0.025) groups. However, the significant difference disappeared in the Aβ+ group when considering the covariates of age, education, total intracranial volume, and APOE4-carrying status. In addition, gLFC connectivity values were negatively correlated with Geriatric Depression Scale scores in the SCD group (r = -0.176, p = 0.047).

CONCLUSION

Women showed lower gLFC connectivity among CU elderly individuals.

Physical and Mental Health Characteristics of 2,962 Adults With Subjective Cognitive Complaints

We investigated subjective cognitive complaints (SCCs), as well as physical and mental health factors, in adults and older adults. U.S. residents (N = 2,962) were recruited via the Amazon Mechanical Turk platform and completed a 90-item survey. Overall, 493/1930 (25.5%) of younger adults and 278/1032 (26.9%) of older adults endorsed SCCs. Analyses revealed worse physical and mental health characteristics in the SCC+ compared to the SCC- group, with primarily medium (Cohen's d = 0.50) to large (0.80) effect sizes. Age did not moderate relationships between SCCs and physical/mental health. Results suggest that SCCs are associated with a diverse set of negative health characteristics such as poor sleep and high body mass index, and lower levels of positive factors, including happiness and wisdom. Effect sizes of psychological correlates were at least as large as those of physical correlates, indicating that mental health is critical to consider when evaluating SCCs.

Cognitive Reserve, Brain Reserve, APOEɛ4, and Cognition in Individuals with Subjective Cognitive Decline in the SILCODE Study

BACKGROUND

Cognitive reserve (CR) and brain reserve (BR) could offer protective effects on cognition in the early stage of Alzheimer's disease (AD). However, the effects of CR or BR on cognition in individuals with subjective cognitive decline (SCD) are not clear.

OBJECTIVE

To explore the effects of CR and BR on cognition in subjects with SCD.

METHODS

We included 149 subjects from the Sino Longitudinal Study on Cognitive Decline (SILCODE) study. Education was used as a proxy for CR, and head circumference was used as a proxy for BR. Multiple linear regression models were conducted to examine the effects of CR and BR on cognitive scores. Furthermore, we assessed differences in effects between APOEɛ4 carriers with SCD (n = 35) and APOEɛ4 non-carriers with SCD (n = 114) and linear trends among 4 reserve levels (low BR/CR, high BR/low CR, low BR/high CR, and high BR/high CR).

RESULTS

Both CR and BR had independent positive effects on multiple cognitive measures in SCD participants, and the effects of CR were greater than those of BR. CR has positive effects on cognitive measures in both APOEɛ4 carriers and non-carriers with SCD. However, the positive effects of BR on cognitive measures were observed in APOEɛ4 non-carriers with SCD but not in APOEɛ4 carriers with SCD. Furthermore, there was a linear trend toward better cognitive performance on all cognitive measures in the BR+/CR+ group, followed by the BR-/CR+, BR+/CR-, and BR-/CR-groups.

CONCLUSION

This study suggests that both CR and BR have the potential to delay or slow cognitive decline in individuals with SCD.

Demographic characteristics and neuropsychological assessments of subjective cognitive decline (SCD) (plus)

BACKGROUND

Since SCD (plus) was standardized, little is known about its demographic characteristics and its outcomes of neuropsychological assessments, including the SCD questionnaire 9 (SCD-Q9).

OBJECTIVE

To characterize SCD (plus) by comparing the neuropsychological features among its subgroups and with normal controls (NC). Also, to explore its demographics and to understand the relation of the chief complaints and the scores of SCD-Q9.

METHODS

Multistage stratified cluster random sampling was conducted to select participants. As a result, 84 NC and 517 SCD (plus) were included. SCD (plus) was further classified into several subgroups (SCD-C: concerned cognitive decline; SCD-F: complaints about SCD within the past five years; SCD-P: feeling performance being not as good as their peers; SCD+: presented> 3 of SCD (plus) features; SCD-: presented ≤ 3 of SCD (plus) features (see the diagnostic criteria for the details)) and between-group comparisons of neuropsychological scores were conducted. Point-biserial correlation and binary logistic regression analyses were performed to investigate the demographic characteristics of its subgroups. Finally, Spearman correlation was used to better understand the relation of SCD (plus) to SCD-Q9.

RESULTS

(1) Scores of AVLT-LR (AVLT-LR: Auditory Verbal Learning Test-Long Delayed Recall) and MoCA-B (MoCA: Montreal Cognitive Assessment-Basic) were lower in the SCD-P group than those in the NC group, and the SCD+ group scored lower in the MoCA-B and CDT(CDT: Clock Drawing Test) than the SCD- group. (2) Females were more concerned than male participants. Individuals with lower education level felt that their cognitive performance were worse than their peers. Also, younger people might express concerns more than the more elderly. People who had complaints of SCD-P might be more likely to report SCD-C, but less likely to report SCD-F. (3) Positive correlations were found between the chief complaints of SCD (plus) and some items of SCD-Q9.

CONCLUSIONS

SCD (plus) may be related to demographic factors. Individuals with SCD (plus) already exhibited cognitive impairment, which can be detected by SCD-Q9.

The Factor Structure of Items Assessing Subjective Memory: Between-Persons and Within-Persons across Time

INTRODUCTION

Current understanding of the psychometric properties of items intended to assess the multidimensional construct of subjective memory (SM) is limited, as longitudinal studies of aging commonly use single items or brief sets of items to assess SM. Investigating how SM items cluster within individuals over time would increase the understanding of how combining these items impacts their utility as an early indicator of cognitive change in the aging trajectory. To address this need, the current study examined the factor structure of a brief set of SM items in an existing longitudinal study focused on cognitive aging at both the within-person and between-person levels.

METHODS

Data were drawn from the Einstein Aging Study, a longitudinal cohort study of aging (N = 1,239, Mage = 77.51, SD = 5.03; 69.50% white; 24.27% black; 6.23% other). Community-dwelling older adults from an urban area of New York City were interviewed annually. At each wave, participants responded to 6 items intended to assess SM. Items assessed participants' perceived memory decline as well as current memory ability. Multilevel exploratory factor analyses examined which factor solution best fit the data at between-person and within-person levels.

RESULTS

Factor structure of the SM items varied at the two levels. At the within-person level, two factors emerged, whereas at the between-person level, a single factor best represented the SM items. Items assessing perceived declines in memory functioning tended to have similar trajectories, while items assessing current memory ability were less related to change over time.

CONCLUSION

Items appeared to assess two different dimensions of SM when examining within-person changes in SM across time; however, the item structure suggested no other items covaried systematically within persons over time. In contrast to the conceptualization of SM as a multidimensional construct, our findings suggest that when measuring SM between individuals, SM items tend to capture a single dimension underlying SM. This may be due to the long retrospection period of items assessing perceived memory ability. A single item assessing perceived memory decline in older adults without evidence of objective cognitive impairment may be sufficient to monitor memory change in clinical or research settings.

GERO Cohort Protocol, Chile, 2017-2022: Community-based Cohort of Functional Decline in Subjective Cognitive Complaint elderly

BACKGROUND

With the global population aging and life expectancy increasing, dementia has turned a priority in the health care system. In Chile, dementia is one of the most important causes of disability in the elderly and the most rapidly growing cause of death in the last 20 years. Cognitive complaint is considered a predictor for cognitive and functional decline, incident mild cognitive impairment, and incident dementia. The GERO cohort is the Chilean core clinical project of the Geroscience Center for Brain Health and Metabolism (GERO). The objective of the GERO cohort is to analyze the rate of functional decline and progression to clinical dementia and their associated risk factors in a community-dwelling elderly with subjective cognitive complaint, through a population-based study. We also aim to undertake clinical research on brain ageing and dementia disorders, to create data and biobanks with the appropriate infrastructure to conduct other studies and facilitate to the national and international scientific community access to the data and samples for research.

METHODS

The GERO cohort aims the recruitment of 300 elderly subjects (> 70 years) from Santiago (Chile), following them up for at least 3 years. Eligible people are adults not diagnosed with dementia with subjective cognitive complaint, which are reported either by the participant, a proxy or both. Participants are identified through a household census. The protocol for evaluation is based on a multidimensional approach including socio-demographic, biomedical, psychosocial, neuropsychological, neuropsychiatric and motor assessments. Neuroimaging, blood and stool samples are also obtained. This multidimensional evaluation is carried out in a baseline and 2 follow-ups assessments, at 18 and 36 months. In addition, in months 6, 12, 24, and 30, a telephone interview is performed in order to keep contact with the participants and to assess general well-being.

DISCUSSION

Our work will allow us to determine multidimensional risks factors associated with functional decline and conversion to dementia in elderly with subjective cognitive complain. The aim of our GERO group is to establish the capacity to foster cutting edge and multidisciplinary research on aging in Chile including basic and clinical research.

TRIAL REGISTRATION

NCT04265482 in ClinicalTrials.gov. Registration Date: February 11, 2020. Retrospectively Registered.

Differences in the Associations Between Memory Complaints and Depressive Symptoms Among Black and White Older Adults

OBJECTIVE

To test whether race (specifically Black or White) moderates the relationship between memory complaints and depressive symptoms in cognitively normal older adults, and if these relationships vary by memory complaint characteristics.

METHODS

Data from Black (n = 551) and White (n = 1,158) cognitively intact participants (Mage = 77.1, SD = 7.5; 76.6% female) in the Minority Aging Research Study and the Rush Memory and Aging Project were used. Participants completed annual clinical evaluations, including the Center for Epidemiologic Studies Depression scale and two memory complaint questions, over periods of up to 18 years. Ordinal mixed effects models were used to examine within-person relationships between memory complaints and depressive symptoms over time, as well as whether race moderated these associations.

RESULTS

Reports of greater memory change over time were associated with more depressive symptoms for both Black and White older adults. However, reports of greater frequency of memory problems were related to depressive symptoms for Black older adults only.

CONCLUSION

Findings suggest differential associations between memory complaints and depressive symptoms in cognitively normal Black and White older adults and call for future research to examine the influence of race and related factors on memory complaints and depressive symptoms.

Personality determinants of subjective executive function in older adults

Objectives: Problems in subjective executive function, the perceived cognitive control of mental processes for goal-directed behavior, may indicate cognitive impairment in older adulthood. Although, previous studies highlight the importance of personality on objective cognitive performance, no studies clarify their role with subjective executive function. To inform methods of early identification of cognitive impairment, this study explored how temperament and personality traits account for problems in subjective executive function.Method: The current project examined the associations between temperament and personality on subjective executive function across two samples of community-dwelling older adults (65+ years, n₁ = 25, n₂ = 50). Both studies measured subjective executive function (Behavioral Rating Inventory of Executive Function-Adult) and separately administered scales on temperament (Adult Temperament Questionnaire) and personality (Big Five Inventory).Results: Concerning temperament, older adults higher in negative affect endorsed greater difficulty in subjective executive function. Regarding personality traits, older adults with higher neuroticism and lower conscientiousness reported higher difficulty in subjective executive function.Conclusion: Findings enhance our understanding of subtle cognitive changes and may aid in early detection. In particular, distressful inclinations were associated with more reported problems in executive function whereas problem-solving tendencies were inversely related. Future work should examine if enhanced negativity coupled with analytical disengagement predicts problems in subjective executive function over time.

Subjective Cognitive Decline May Be a Stronger Predictor of Incident Dementia in Women than in Men

BACKGROUND/OBJECTIVE

Subjective cognitive decline (SCD) has often been associated with an increased risk for subsequent dementia. However, sex-specific associations are understudied until now.

METHODS

Cross-sectional and longitudinal associations over a follow-up period of up to 13 years were investigated in a sample of participants without objective cognitive impairment at baseline (n = 2,422, mean age = 79.63 years). Logistic regression and Cox proportional hazards models were conducted.

RESULTS

Women less frequently reported SCD without worries (p < 0.001), but tended to report more often SCD with worries (p = 0.082) at baseline compared to men. In models adjusted for age, education, cognitive status, and depressive symptoms, SCD at baseline increased the risk for subsequent dementia (p < 0.001), and this effect was less pronounced in males (interaction sex×SCD: p = 0.022). Stratified analyses showed that SCD increased the risk for subsequent dementia in women (HR = 1.77, p < 0.001), but not in men (HR = 1.07, p = 0.682). Similar results were found in analyses with SCD without and with worries, except that SCD with worries also predicted subsequent Alzheimer's disease (AD) in men (p = 0.037).

CONCLUSION

At baseline, men reported more SCD without worries and women tended to report more SCD with worries. SCD in women was more strongly associated with subsequent dementia. SCD without and with worries was related to incident dementia and AD in women, whereas in men only SCD with worries increased the risk for AD, but not for all-cause dementia.

Association Between Cognitive Test Performance and Subjective Cognitive Decline in a Diverse Cohort of Older Adults: Findings From the KHANDLE Study

BACKGROUND

Subjective cognitive decline (SCD) may represent a low-burden indicator of dementia risk. The value of SCD as a proxy marker, however, depends on the consistency of associations between subjective and objective cognitive measures across sociodemographic and psychological factors.

METHODS

We evaluated baseline data from the Kaiser Healthy Aging and Diverse Life Experiences (KHANDLE) study (n=1615). SCD was measured using the 12-item Everyday Cognition (ECog) scale. Using linear regression models with interaction terms, we evaluated 6 potential modifiers (age, sex, race/ethnicity, educational attainment, family history of dementia, and depressive symptoms) of the association between cognitive performance (episodic memory, executive function) and SCD.

RESULTS

Lower episodic memory and executive function scores were associated with higher log(ECog scores) (more SCD). Older age and elevated depressive symptoms were associated with higher log(ECog scores). Age (interaction P=0.002) and education (interaction P=0.01) modified the association between executive function and log(ECog scores). Specifically, associations between executive function and log(ECog scores) were stronger among participants with more education and less pronounced among older participants.

CONCLUSIONS

The association between cognitive performance and log(ECog scores) differed little across sociodemographic and psychological factors. SCD as measured by the ECog may be a valuable proxy for cognitive performance in diverse older adults.

Lifestyle Factors and Subjective Cognitive Impairment in Patients Seeking Help at a Memory Disorder Clinic: The Role of Negative Life Events

BACKGROUND/AIMS

A large proportion of patients at memory disorders clinics are classified as having subjective cognitive impairment (SCI). Previous research has investigated whether particular lifestyle factors known to affect cognition can be useful in differentiating patients who do not show objective evidence of memory decline. There may also exist subgroups of patients with respect to lifestyle factors that could help clinicians to understand the patient group that presents to memory clinics. These may differ in diagnostic outcome. Very little is known about potential subgroups; however, but such information may help guide interventions and potentially eliminate unnecessary diagnostic procedures. The current study investigated patterns of lifestyle-related variables, including stress, sleep, sensory sensitivity, depression, and negative life events in patients presenting to a memory disorders clinic. The aim was to determine whether subgroups existed and whether it was possible to distinguish those with objectively impaired cognition.

METHODS

One hundred and seventy-eight patients (mean age 58 years) from a University Hospital Memory Disorders Clinic.

RESULTS

Cluster analysis identified three groups of lifestyle-related variables. Strong determinants of clusters were negative life events and age. Patients with a high number of negative life events also tended to have highest self-reported memory complaint, higher levels of stress, depression, and sensory sensitivity. However, they did not perform the worst on memory testing. In contrast, individuals who performed the worst on memory tests were older, tended to have the least memory complaints, and less negative lifestyle factors; this group also included the highest proportion of patients with mild cognitive impairment and had the lowest median amyloid A-beta 42 (Aβ42). The group with the best cognitive performance were younger, included the highest proportion of patients with SCI and the highest median Aβ42. On lifestyle variables, their ratings fell in between the other groups.

CONCLUSIONS

Lifestyle subgroups of patients were determined by stress, emotional problems, and age. The groups were significantly associated with Aβ42 and diagnostic outcome. This pattern may confound the differentiation between objective and subjective memory problems. Asking about lifestyle variables, in conjunction with neuropsychological testing, could potentially identify individuals who are not likely to have objective memory impairment and guide interventions.

Subjective Memory Complaints in White and African American Participants

OBJECTIVE

Subjective memory complaints (SMCs) are associated with mild cognitive impairment and dementia but are understudied in African Americans (AAs). We compared SMC endorsement in white and AA participants and evaluated predictors of diagnostic progression.

METHODS

Initial visit variables, including SMC and memory performance, were compared within a cognitively normal race-matched sample of white and AA participants (N_total = 912; 456_{each race}) to assess the presence and predictors of SMC, the predictors of future diagnostic progression, and the change in memory performance over time.

RESULTS

More white (32.9%) than AA (24.3%) participants reported SMC (P < .01, ϕ = -.10). Subjective memory complaint was predicted by memory performance (B = -0.03, standard error [SE] = 0.013, odds ratio [OR] = .968, P < .05) and race (B = -0.99, SE = 0.080, OR = .373, P < .001). Subjective memory complaints and memory performance were associated with progression, χ² (3, n = 912) = 102.37, P < .001. African American race (-2.05 ± 0.24 SE) and SMC (-0.45 ± 0.21 SE) were associated with worse memory performance at baseline and over time, χ²(3) = 13.54, P < .01.

CONCLUSIONS

In contrast to previous research, our study found that SMC is associated with diagnostic progression and objective memory declines in both white and AA participants.

A comparative study on the validations of three cognitive screening tests in identifying subtle cognitive decline

Background

Subtle cognitive decline (SCD) may represent a very early stage of objective cognitive impairment before mild cognitive impairment (MCI), with less neuronal damage and more functional reservation. Detecting individuals with SCD is imperative for dementia prevention and treatment. In this study, we aimed to compare the validations of three cognitive screening tests, Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment-Chinese Version (MoCA-CV), and Memory and Executive Screening (MES), in identifying subtle cognitive decline.

Methods

A total of 407 individuals were recruited, including 147 cognitively normal controls (NC), 102 individuals with subtle cognitive decline (SCD) and 158 individuals with mild cognitive impairment (MCI) according to the operational neuropsychological criteria proposed by Jak and Bondi’s. All participants underwent standardized comprehensive neuropsychological tests and the three cognitive screening tests. Chi-square analysis was used to compare the cognitive performance among the groups of NC, SCD and MCI. Receiver operating characteristic (ROC) curves were used to evaluate the abilities of MMSE, MoCA-CV and MES in discriminating NC, SCD and MCI.

Results

Compared with NC, SCD showed a significant decline only in the tests of memory, such as Auditory Verbal Learning Test (AVLT), Rey-Osterrieth Complex Figure Test (CFT) and Prospective Memory Test (PrM) (P < 0.01). However, MCI showed significant decline in all cognitive performances (P < 0.01). The scores of MMSE, MoCA-CV and MES all showed a progressive downward trend within the groups of NC, SCD and MCI (P < 0.001). In ROC Analyses for discriminating individuals with SCD from NC, the most appropriate MES cutoff was 84, with a sensitivity of 74.3%, a specificity of 60.8% and 0.738 for AUC (95%CI, 0.675–0.801). By contrast, MMSE and MOCA-CV had poor sensitivity (67.4 and 70.8%, respectively) and specificity (51.0 and 52.9%, respectively), and smaller AUCs (0.643 and 0.644, respectively) than the MES.

Conclusion

As a screening test, MES is more efficacious in identifying SCD from normal controls than MMSE and MoCA-CV.

Predicting current and future anxiety symptoms in cognitively intact older adults with memory complaints

OBJECTIVES

Memory complaints are a common concern for older adults and may co-occur with anxiety symptoms. Although both memory complaints and anxiety are associated with heightened cognitive decline risk, little is known about how these symptoms develop over time. The purpose of this study was to examine the differential concurrent and longitudinal relationships among anxiety symptoms and two types of memory complaints in cognitively intact older adults.

METHODS/DESIGN

The current study sample was drawn from two longitudinal, nationally representative datasets, the National Health and Aging Trends Study (NHATS) and the Health and Retirement Study (HRS). Cognitively intact older adults aged 65 and over were included, representing six (n = 5069; NHATS) and two (n = 5284; HRS) waves of data, respectively. Using multilevel linear modeling, we tested bidirectional relationships between anxiety and two types of memory complaints: current rating of memory performance and perceived memory decline.

RESULTS

Concurrent associations between anxiety symptoms and memory complaints were found in both datasets: At times when current memory performance was rated more poorly or perceived memory decline was reported, anxiety symptoms tended to be higher, and vice versa. A longitudinal relationship was identified in NHATS such that perceived memory decline, and not current memory rating, predicted future anxiety symptoms.

CONCLUSION

This study provides a better understanding of the relationships between memory complaints and anxiety symptoms over time. Cognitively intact older adults with perceived memory decline are at greater risk for current as well as future anxiety symptoms.

The factors associated with subjective cognitive decline and cognitive function among older adults

AIMS

To explore the risk factors for subjective cognitive decline and cognitive function among older adults in South Korea.

DESIGN

This study employed a descriptive cross-sectional design.

METHODS

A convenience sample of 182 patients was recruited from a senior welfare center in Seoul. The mean age of the participants was 78.4 years (SD 5.91). Among them, 64.3% were women. The data were collected by a trained research assistant using structured questionnaires from September 2016-February 2017. Demographic characteristics, comorbidities, depression, physical and cognitive activity levels, instrumental activities of daily living, subjective cognitive decline, and cognitive function were assessed. Student's t tests, chi-square tests, and hierarchical multiple regression analyses were used for statistical analyses.

RESULTS

The findings revealed that 37.4% of the participants were not cognitively intact. Depression, perceived health status, and cognitive function were significantly associated with subjective cognitive decline (F = 7.10, p < .001, adjusted R²  = 25.3). Age, educational level, perceived health status, and subjective cognitive decline were significantly related to cognitive function (F = 20.98, p < .001, adjusted R²  = 47.0). After controlling for these variables, cognitive activity was significantly and independently related to cognitive function.

CONCLUSION

The results suggest that for the maintenance of cognitive function, cognitive activity should be encouraged. In addition, older adults who complain of subjective cognitive decline and have risk factors such as depression need therapeutic interventions to prevent actual decrease of cognitive function.

IMPACT

The present findings advance prior knowledge by considering variables such as physical and cognitive activity levels to provide novel evidence that can be used to develop interventions for community-dwelling older adults. Thus, to be effective, nursing interventions must seek to improve cognitive function through intellectual stimulation.

Spatiotemporal Oscillatory Patterns During Working Memory Maintenance in Mild Cognitive Impairment and Subjective Cognitive Decline

Working memory (WM) is a crucial cognitive process and its disruption is among the earliest symptoms of Alzheimer’s disease. While alterations of the neuronal processes underlying WM have been evidenced in mild cognitive impairment (MCI), scarce literature is available in subjective cognitive decline (SCD). We used magnetoencephalography during a WM task performed by MCI [Formula: see text], SCD [Formula: see text] and healthy elders [Formula: see text] to examine group differences during the maintenance period (0–4000[Formula: see text]ms). Data were analyzed using time–frequency analysis and significant oscillatory differences were localized at the source level. Our results indicated significant differences between groups, mainly during the early maintenance (250–1250[Formula: see text]ms) in the theta, alpha and beta bands and in the late maintenance (2750–3750[Formula: see text]ms) in the theta band. MCI showed lower local synchronization in fronto-temporal cortical regions in the early theta–alpha window relative to controls [Formula: see text] and SCD [Formula: see text], and in the late theta window relative to controls [Formula: see text] and SCD [Formula: see text]. Early theta–alpha power was significantly correlated with memory scores [Formula: see text] and late theta power was correlated with task performance [Formula: see text] and functional activity scores [Formula: see text]. In the early beta window, MCI showed reduced power in temporo-posterior regions relative to controls [Formula: see text] and SCD [Formula: see text]. Our results may suggest that these alterations would reflect that memory-related networks are damaged.

Risk Factors and Neuropsychological Assessments of Subjective Cognitive Decline (plus) in Chinese Memory Clinic

Background

Since subjective cognitive decline (SCD) was standardized in 2014, many studies have investigated its features. However, the risk of SCD (plus) progressing to AD is much higher, and yet there have been few studies reporting the risk factors and neuropsychological assessment characteristics of SCD (plus).

Objective

To characterize SCD (plus) by comparing it with normal control (NC), amnesic mild cognitive impairment (aMCI), and Alzheimer Disease (AD) regarding their demographics, lifestyle, family history of dementia, multimorbidity and the neuropsychological assessments.

Methods

A total of 135 participants were recruited, including 23 NC, 30 SCD (plus), 45 aMCI and 37 AD. Descriptive statistics were provided. A logistic regression model was used to analyze the affecting factors of SCD (plus), and finally the Receiver Operating Characteristic (ROC) analysis was applied to distinguish between SCD (plus) and NC.

Results

(1) SCD (plus) group was younger than both the aMCI group and AD group. It consisted of more participants with mental work and higher body mass index (BMI) than the AD group. (2) Scores of Auditory Verbal Learning Test - Immediate recall (AVLT-IR) and AVLT-Long delayed recall (AVLT-LR) decreased in the following order: NC→SCD (plus)→aMCI→AD. (3) The Area Under Curve (AUC) for discriminating SCD (plus) and NC group was from 0.673 to 0.838.

Conclusion

Aging is an important risk factor of both NC progressing to SCD (plus), and SCD (plus) progressing to aMCI or AD. In addition to aging, lower education level and lower BMI were significantly associated with greater odds of SCD (plus) progressing to aMCI or AD patients, whereas mental work was a protective factor of SCD (plus) progressing to AD. Finally, AVLT is a sensitive indicator of the cognitive decline and impairment in SCD (plus) in relative to normal controls.

Subjective Cognitive Decline, Objective Cognition, and Depression in Older Hispanics Screened for Memory Impairment

Subjective cognitive decline (SCD) is common in older adults and may be an early marker of future cognitive decline. Research suggest that SCD is more closely related to concurrent symptoms of depression than to objective cognitive performance in non-Hispanic Whites, but it is unknown whether the associations of SCD, cognition, and depression manifest differently in Hispanic older adults. We examined if SCD is associated with objective cognitive performance or with depression symptoms in 145 Hispanic individuals ages 60 or older referred by community health clinics for screening of cognitive complaints. All participants lived near the U.S.-Mexico border, spoke Spanish only, or were Spanish-English bilingual. Memory-only and global cognitive composites were created from scores on Spanish versions of several neuropsychological tests. The Geriatric Depression Scale (GDS) and a five-item SCD questionnaire developed by our group were also completed. Multiple regression analyses showed no significant associations between SCD and memory or global cognitive composite scores after adjusting for age, sex, education, and GDS score. In contrast, there was a significant association between GDS and SCD after adjusting for age, sex, education, global and memory composite scores. Findings suggest that SCD does not accurately reflect current cognitive status in older Hispanics who present to their primary care physician with cognitive complaints. Clinicians should interpret SCD in this population within the context of information about symptoms of depression. Longitudinal research is needed in older Hispanics to better characterize SCD in this population and to determine if it can predict future cognitive decline.

Anxiety correlates with cortical surface area in subjective cognitive decline: APOE ε4 carriers versus APOE ε4 non-carriers

Background

Subjective cognitive decline (SCD) is characterized by self-reported cognitive deficits without measurable cognitive impairment. It has been suggested that individuals with SCD exhibited brain structural alterations in widespread cortical thinning or gray matter loss in the medial temporal and frontotemporal regions. Apolipoprotein E (APOE) ε4 allele is thought to be a genetic marker associated with risk of SCD. Neuropsychiatric symptoms may provide insight in detecting higher-risk elders for early Alzheimer’s disease as well. Therefore, we aim to explore the characteristics of brain morphology in SCD and to determine whether it is influenced by APOE ε4 as well as neuropsychiatric symptoms in SCD.

Methods

A total of 138 cognitively normal older individuals from the SILCODE cohort underwent a clinical interview, neuropsychological assessments, a blood test, and MRI. A two-sample t-test was used to examine the cortex volume and bilateral cortical surface area alterations between SCD (n = 65) and controls (n = 73). A general linear model analysis was used to test for both main and interaction effects of clinical phenotype (SCD vs. controls) and APOE on global and regional cortex volume and bilateral cortical surface area and thickness. A multiple linear regression analysis was conducted to determine the effects of the APOE genotype on the relationships between morphometric features and neuropsychiatric symptoms in SCD.

Results

Compared with controls, individuals with SCD showed decreased total cortical volumes and cortical surface area. SCD APOE ε4 carriers showed additive reduction in the right cortical surface area. The evaluation scores of anxiety symptoms were negatively associated with the right cortical surface area in SCD APOE 4 non-carriers.

Conclusions

Individuals with SCD had an altered cortical surface area, and APOE genotype and anxiety symptoms are modified factors on the cortical surface area decrease in SCD.

Trial registration

ClinicalTrials.gov (Identifier: NCT03370744). Registered 15 March 2017.

Electronic supplementary material

The online version of this article (10.1186/s13195-019-0505-0) contains supplementary material, which is available to authorized users.

Gender-Specific Relationship Between Executive Function and Self-Rated Health

Objectives

Self-rated health is a comprehensive measure of health. As gender difference in self-rated health is found, identifying gender-specific factors related to self-rated health is important. Poor executive functioning negatively affects an individual’s independence and healthy lifestyle, but it is unknown relationships between executive function and self-rated health and gender differences in these relationships. Therefore, gender differences were examined in the relationship between executive function and self-rated health in the community.

Methods

Individuals completed questionnaires about their health status and subjective decline in executive function. Neuropsychological tests were also performed to assess objective executive functioning. Two separate multivariable linear regression analyses were conducted by gender.

Results

Better objective executive function was related to greater self-rated health scores (better self-rated health) in men alone (βs = 0.341), while better subjective executive function was significantly associated with greater self-rated health scores in both men and women (βs = 0.385 and 0.443, respectively).

Conclusion

Gender differences are important when reporting perceived health status, in particular the different effects of subjective and objective executive function on self-rated health across genders. Clinicians need to be aware of the potential value of subjective executive function complaints when evaluating health status.

Levels of α-2 Macroglobulin in cognitively normal Mexican- Americans with Subjective Cognitive Decline: A HABLE Study

BACKGROUND

The presence of Subjective Cognitive Decline (SCD) in the absence of objective change and the inflammatory biomarker Alpha 2 Macroglobulin (A2M) have both been implicated in preclinical Alzheimer's disease. Mexican Americans are population with high rates of cardiovascular and inflammatory disorders.

OBJECTIVES

The current study investigated the levels of A2M in cognitively normal Mexican Americans with and without complaints of cognitive decline.

METHOD

293 (243 females, 50 males) community-based cognitively normal older Mexican Americans from the ongoing Health and Aging Brain among Latino Elders (HABLE) study were grouped based on subjective cognitive decline and blood samples were assayed by electrochemiluminescence to determine levels of A2M.

RESULTS

Participants with SCD had significantly higher levels of A2M than those without SCD. Females with SCD had a significantly higher level of A2M.

CONCLUSIONS

Results suggest that higher levels of A2M, a marker of neuronal injury, may be involved in subtle changes in cognitive functioning recognizable to persons reporting SCD but too subtle to be objectively measured. Longitudinal research is needed to assess the impact of SDC and A2M in progression to MCI and dementia in Mexican Americans.

Clinical and Biomarker Characteristics According to Clinical Spectrum of Alzheimer's Disease (AD) in the Validation Cohort of Korean Brain Aging Study for the Early Diagnosis and Prediction of AD

We aimed to present the study design of an independent validation cohort from the Korean Brain Aging Study for the Early Diagnosis and Prediction of Alzheimer's disease (AD) (KBASE-V) and to investigate the baseline characteristics of the participants according to the AD clinical spectrum. We recruited 71 cognitively normal (CN) participants, 96 with subjective cognitive decline (SCD), 72 with mild cognitive impairment (MCI), and 56 with AD dementia (ADD). The participants are followed for three years. The Consortium to Establish a Registry for AD scores was significantly different between all of the groups. The logical memory delayed recall scores were significantly different between all groups, except between the MCI and ADD groups. The Mini-Mental State Examination score, hippocampal volume, and cerebrospinal fluid (CSF) amyloid-β42 level were significant difference among the SCD, MCI, and ADD groups. The frequencies of participants with amyloid pathology according to PET or CSF studies were 8.9%, 25.6%, 48.3%, and 90.0% in the CN, SCD, MCI, and ADD groups, respectively. According to ATN classification, A+/T+/N+ or A+/T+/N- was observed in 0%, 15.5%, 31.0%, and 78.3% in the CN, SCD, MCI, and ADD groups, respectively. The KBASE-V showed a clear difference according to the AD clinical spectrum in neuropsychological tests and AD biomarkers.

Lifestyle Factors Are Important Contributors to Subjective Memory Complaints among Patients without Objective Memory Impairment or Positive Neurochemical Biomarkers for Alzheimer's Disease

Background/Aims

Many patients presenting to a memory disorders clinic for subjective memory complaints do not show objective evidence of decline on neuropsychological data, have nonpathological biomarkers for Alzheimer's disease, and do not develop a neurodegenerative disorder. Lifestyle variables, including subjective sleep problems and stress, are factors known to affect cognition. Little is known about how these factors contribute to patients' subjective sense of memory decline. Understanding how lifestyle factors are associated with the subjective sense of failing memory that causes patients to seek a formal evaluation is important both for diagnostic workup purposes and for finding appropriate interventions and treatment for these persons, who are not likely in the early stages of a neurodegenerative disease. The current study investigated specific lifestyle variables, such as sleep and stress, to characterize those patients that are unlikely to deteriorate cognitively.

Methods

Two hundred nine patients (mean age 58 years) from a university hospital memory disorders clinic were included.

Results

Sleep problems and having much to do distinguished those with subjective, but not objective, memory complaints and non-pathological biomarkers for Alzheimer's disease.

Conclusions

Lifestyle factors including sleep and stress are useful in characterizing subjective memory complaints from objective problems. Inclusion of these variables could potentially improve health care utilization efficiency and guide interventions.

Effect of Alzheimer's disease risk and protective factors on cognitive trajectories in subjective memory complainers: An INSIGHT-preAD study

INTRODUCTION

Cognitive change in people at risk of Alzheimer's disease (AD) such as subjective memory complainers is highly variable across individuals.

METHODS

We used latent class growth modeling to identify distinct classes of nonlinear trajectories of cognitive change over 2 years follow-up from 265 subjective memory complainers individuals (age 70 years and older) of the INSIGHT-preAD cohort. We determined the effect of cortical amyloid load, hippocampus and basal forebrain volumes, and education on the cognitive trajectory classes.

RESULTS

Latent class growth modeling identified distinct nonlinear cognitive trajectories. Education was associated with higher performing trajectories, whereas global amyloid load and basal forebrain atrophy were associated with lower performing trajectories.

DISCUSSION

Distinct classes of cognitive trajectories were associated with risk and protective factors of AD. These associations support the notion that the identified cognitive trajectories reflect different risk for AD that may be useful for selecting high-risk individuals for intervention trials.

Memory concerns in the early Alzheimer's disease prodrome: Regional association with tau deposition

Introduction

Relationship between self– and informant memory concerns and tau aggregation was assessed in adults at risk for Alzheimer's disease (AD).

Methods

Regional mean standardized uptake value ratios were extracted from [¹⁸F]flortaucipir positron emission tomography (PET) scans of 82 at-risk adults in the Alzheimer's Disease Neuroimaging Initiative (ADNI) cohort. Associations between self– and informant ECog memory scores and tau aggregation were analyzed on both regional and voxelwise bases. Analyses were completed both on the whole sample and restricted to amyloid-positive individuals only.

Results

Memory concerns were associated with tau aggregation. Self-perception was more associated with frontal tau. In contrast, informant scores were more associated with parietal tau. This source-by-region interaction was more prominent in amyloid-positive participants and observed in both regional and voxelwise analyses.

Discussion

Quantitative assessment of perceived memory functioning may be useful for screening older adults at risk for Alzheimer's disease. Individuals and their informants may provide complementary information relating to the anatomical distribution of tau.

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Both self– and informant memory concerns are associated with tau aggregation in at-risk adults.

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Self-concerns are more associated with frontal tau compared to a parietal pattern for informant concerns.

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This pattern is strongest in amyloid-positive participants.

Cross-sectional variations of white and grey matter in older hypertensive patients with subjective memory complaints

Mild cognitive impairment and Alzheimer's dementia involve a grey matter disease, quantifiable by ¹⁸F-Fluorodeoxyglucose positron emission tomography (FDG-PET), but also white matter damage, evidenced by diffusion tensor magnetic resonance imaging (DTI), which may play an additional pathogenic role. This study aimed to determine whether such DTI and PET variations are also interrelated in a high-risk population of older hypertensive patients with only subjective memory complaints (SMC).

Sixty older hypertensive patients (75 ± 5 years) with SMC were referred to DTI and FDG-PET brain imaging, executive and memory tests, as well as peripheral and central blood pressure (BP) measurements. Mean apparent diffusion coefficient (ADC_mean) was determined in overall white matter and correlated with the grey matter distribution of the metabolic rate of glucose (CMRGlc) using whole-brain voxel-based analyses of FDG-PET images.

ADC_mean was variable between individuals, ranging from 0.82 to 1.01.10^− 3 mm² sec^− 1, and mainly in relation with CMRGlc of areas involved in Alzheimer's disease such as internal temporal areas, posterior associative junctions, posterior cingulum but also insulo-opercular areas (global correlation coefficient: − 0.577, p < 0.001). Both the ADC_mean and CMRGlc of the interrelated grey matter areas were additionally and concordantly linked to the results of executive and memory tests and to systolic central BP (all p < 0.05).

Altogether, our findings show that cross-sectional variations in overall white brain matter are linked to the metabolism of Alzheimer-like cortical areas and to cognitive performance in older hypertensive patients with only subjective memory complaints. Additional relationships with central BP strengthen the hypothesis of a contributing pathogenic role of hypertension.

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Changes in grey and white matter are interrelated in elderly hypertensive patients.

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They can be documented in the absence of any objective memory complaint.

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These interrelationships are associated with cognitive test results.

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The interrelated grey matter areas are likely to define an Alzheimer-like pattern.

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These interrelationships are linked to the level of central blood pressure.