Longitudinal Relationships Between Subjective Cognitive Decline and Objective Memory: Depressive Symptoms Mediate Between-Person Associations

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.

Poor-Quality Daily Social Encounters, Daily Stress, and Subjective Cognitive Decline Among Older Adults

Background and Objectives

Although prior research has shown that social relationships and daily stress are strongly associated with cognitive function, few studies have explored the link between the quality of daily social encounters and subjective cognitive decline (SCD). The present study explores whether the quality of older adults' daily social encounters is associated with SCD through daily stress.

Research Design and Methods

This study used data from 254 adults aged 70 or older (M age  = 76.5 years, SD = 4.4; 67.7% women) who completed the Einstein Aging Study, a 2-week experience sampling study. Multilevel mediation analyses were conducted to account for daily measurements nested within individuals. We tested the indirect effect of the quality of daily social encounters on SCD through daily stress levels.

Results

There was a significant positive association between ambivalent and neutral social encounters and daily stress levels at both the within- and between-person levels. Between-person daily stress was, in turn, associated with greater SCD. Specifically, there was a significant indirect path from ambivalent social encounters to SCD through daily stress.

Discussion and Implications

This study contributes to a more detailed understanding of how the quality of daily social encounters can influence cognition via increased exposure to daily stress. The findings suggest that emotional support may be crucial to preserving perceptions of older adults' cognitive functioning.

Sleep Quality and Subjective Cognitive Decline among Older Adults: The Mediating Role of Anxiety/Depression and Worries

Background

Subjective cognitive decline (SCD) in older individuals has been implicated as a possible precursor to Alzheimer's disease. Poor sleep quality and anxiety/depressive symptoms have been linked to the progression of SCD, but these associations and older adults' worries have yet to be fully established in the Chinese older adult population, which is one of the largest in the world. The aim of this study was to explore the relationship between sleep quality, anxiety/depression symptoms, and worries, and SCD prevalence among Chinese community-dwelling older individuals.

Methods

A total of 707 adults aged between 60 and 99 from Shanghai, China, completed self-report questionnaires that covered their cognitive and mental well-being, as well as demographic information. Subjective cognitive decline (SCD) was evaluated using the memory/cognition syndromes of the old adult self-report (OASR). Sleep quality, anxiety/depression, and worries were measured from their respective sections of the OASR.

Results

The general linear regression models showed that poorer sleep quality was associated with an increased prevalence of anxiety/depression symptoms, worries, and SCD among older adults. As suggested by the mediation analysis, anxiety/depression and worries were significant mediators in the relationship between sleep quality and SCD prevalence, and these two factors also have a serial mediation effect between sleep quality and SCD prevalence.

Conclusions

Poorer sleep quality is associated with a higher rate of SCD among older adults, and a higher prevalence of anxiety/depression and worries mediate this relationship, suggesting possible mechanism pathways that lead to SCD. These factors may provide the basis for early, targeted interventions for older adults' mental health preservation and improved quality of life.

Unraveling the Threads: Sleep Difficulties, Neighborhood Physical Disorder, and Subjective Cognitive Decline in Older Americans

Background

Research suggests that the neighborhood in which people live can be a risk or protective factor for various health outcomes, including cognitive decline to Alzheimer's disease. Similar to the impact of neighborhood on health outcomes, sleep difficulties have been linked to cognitive function in older adults. However, few studies have examined how neighborhood physical disorders moderate the effects of sleep on subjective cognitive decline (SCD).

Objective

The study examined the moderating effect of neighborhood factors on the relationship between sleep difficulties and SCD.

Methods

Data were obtained from 2,494 respondents (1,065 males and 1,429 females) from Wave 11 of the National Health and Aging Trends (NHATS) data. Sleep difficulties were operationalized as the presence of difficulties in falling and staying asleep. Neighborhood physical disorder (e.g., vandalism, graffiti) was based on interviewer observations of respondents' neighborhoods. SCD was operationalized as subjective reports of increasing or worse memory loss in the past 12 months and present memory rating. We utilized Linear regression to test neighborhood physical disorder as a moderator of the relationship between sleep difficulties and SCD.

Results

We found a significant interaction between sleep difficulties and neighborhood physical disorder on SCD (β=0.046, p = 0.031, 95% CI[0.00,0.51], p < 0.001). Participants who reported higher average sleep difficulties and higher levels of neighborhood physical disorder were more likely to report SCD.

Conclusions

Our findings add to inform future health interventions and policy recommendations that address modifiable sources of cognitive decline and risk of Alzheimer's disease.

Influence of psychological factors on the relationship between subjective and objective memory in adults with pharmacoresistant temporal lobe epilepsy

PURPOSE

Many adults with temporal lobe epilepsy (TLE) report subjective cognitive impairment; however, prior studies have shown a discrepancy between these subjective complaints and objective cognitive deficits on neuropsychological measures. Mood disorders/symptoms are also common in TLE and have been linked to greater subjective cognitive difficulties. To further understand these relationships, this retrospective study sought to determine if symptoms of depression and anxiety moderate or mediate the relationship between subjective cognitive impairment and objective cognitive performance in adults with TLE.

METHOD

Participants were 345 adults (mean age = 40.7; 55 % female) with pharmacoresistant TLE who completed self-report screening measures of depression, anxiety, and subjective cognitive function along with objective memory measures as part of a pre-surgical clinical neuropsychological evaluation. A series of linear regression analyses was conducted to examine the potential moderating and mediating effects of mood on the relationship between subjective and objective memory function after adjusting for relevant covariates.

RESULTS

Consistent with existing literature, self-reported depression and anxiety symptoms were significantly correlated with subjective memory difficulties across all scales (all p < .001). Subjective memory impairment was also significantly correlated with objective memory performance on neuropsychological measures, albeit with small effect sizes (estimate range 0.04-0.20). Contrary to our hypothesis, depression and anxiety did not moderate or mediate the relationship between subjective memory complaints and objective memory performance.

CONCLUSIONS

While symptoms of depression and anxiety were associated with subjective memory ability in this cohort of adults with TLE, this study suggests that mood symptoms do not fully explain the relationship between subjective and objective memory function, likely reflecting the complex and multifactorial relationships among these variables. Nevertheless, our results highlight the importance of screening for depression and anxiety symptoms and assessing patients' subjective memory complaints as part of a neuropsychological evaluation as each of these factors tap into a different aspect of the patient functioning.

Health-related quality of life in subjective cognitive decline and mild cognitive impairment: a longitudinal cohort analysis

BACKGROUND

Health-related quality of life (HR-QoL) is an important outcome for patients and crucial for demonstrating the value of new treatments. Health utility estimates in subjective cognitive decline (SCD) and mild cognitive impairment (MCI) are limited, especially in biomarker-confirmed populations. Besides, little is known about the longitudinal HR-QoL trajectory. This study aims to provide health utility estimates for SCD and MCI and investigate the QoL trajectory along the disease continuum.

METHODS

Longitudinal data from 919 SCD and 1336 MCI patients from the MEMENTO cohort were included. SCD was defined as clinical dementia rating (CDR) = 0, and MCI as CDR = 0.5. HR-QoL was measured using the EQ-5D-3L patient-reported instrument. Linear mixed-effect models (LMM) were used to assess the longitudinal change in HR-QoL and identify predictors of these changes.

RESULTS

Baseline health utilities were 0.84 ± 0.16 and 0.81 ± 0.18, and visual analogue scale (VAS) were 75.8 ± 14.82 and 70.26 ± 15.77 in SCD and MCI. In amyloid-confirmed cases, health utilities were 0.85 ± 0.14 and 0.86 ± 0.12 in amyloid-negative and amyloid-positive SCD, and 0.83 ± 0.17 and 0.84 ± 0.16 in amyloid-negative and amyloid-positive MCI. LMM revealed an annual decline in health utility of - 0.015 (SE = 0.006) and - 0.09 (SE = 0.04) in moderate and severe dementia (P < 0.05). There was a negative association between clinical stage and VAS where individuals with MCI, mild, moderate, and severe dementia were on average 1.695 (SE = 0.274), 4.401 (SE = 0.676), 4.999 (SE = 0.8), and 15.386 (SE = 3.142) VAS points lower than individuals with SCD (P < 0.001). Older age, female sex, higher body mass index, diabetes, cardiovascular history, depression, and functional impairment were associated with poor HR-QoL. Amyloid positivity was associated with an annual decline of - 0.011 (SE = 0.004, P < 0.05) health utility over time.

CONCLUSIONS

Health utility estimates from this study can be used in economic evaluations of interventions targeting SCD and MCI. Health utility declines over time in moderate and severe dementia, and VAS declines with advancing clinical stages. Amyloid-positive patients show a faster decline in health utility indicating the importance of considering biomarker status in HR-QoL assessments. Future research is needed to confirm the longitudinal relationship between amyloid status and HR-QoL and to examine the level at which depression and IADL contribute to HR-QoL decline in AD.

A Traitlike Dimension of Subjective Memory Concern Over 30 Years Among Adult Male Twins

Importance

Subjective memory concern has long been considered a state-related indicator of impending cognitive decline or dementia. The possibility that subjective memory concern may itself be a heritable trait is largely ignored, yet such an association would substantially confound its use in clinical or research settings.

Objective

To assess the heritability and traitlike dimensions of subjective memory concern and its clinical correlates.

Design, Setting, and Participants

This longitudinal twin cohort study was conducted from 1967 to 2019 among male adults with a mean (SD) age of 37.75 (2.52) years to follow-up at mean ages of 56.15 (2.72), 61.50 (2.43), and 67.35 (2.57) years (hereafter, 38, 56, 62, and 67 years, respectively) in the Vietnam Era Twin Study of Aging. The study included a national community-dwelling sample with health, education, and lifestyle characteristics comparable to a general sample of US men in this age cohort. Participants were monozygotic and dizygotic twins randomly recruited from the Vietnam Era Twin Registry. Data were analyzed from May 2021 to December 2022.

Main Outcomes and Measures

Measures included subjective memory concern at 4 time points; objective memory, depressive symptoms, and anxiety at the last 3 time points; negative emotionality (trait neuroticism) at age 56 years; polygenic risk scores (PRSs) for neuroticism, depression, and Alzheimer disease; APOE genotype; and parental history of dementia. Primary outcomes were heritability and correlations between subjective memory concern and other measures.

Results

The sample included 1555 male adults examined at age 38 years, 520 at age 56 years (due to late introduction of subjective memory concern questions), 1199 at age 62 years, and 1192 at age 67 years. Phenotypically, subjective memory concerns were relatively stable over time. At age 56 years, subjective memory concern had larger correlations with depressive symptoms (r, 0.32; 95% CI, 0.21 to 0.42), anxiety (r, 0.36; 95% CI, 0.18 to 0.51), and neuroticism (r, 0.34; 95% CI, 0.26 to 0.41) than with objective memory (r, -0.24; 95% CI, -0.33 to -0.13). Phenotypic results were similar at ages 62 and 67 years. A best-fitting autoregressive twin model indicated that genetic influences on subjective memory concern accumulated and persisted over time (h2 = 0.26-0.34 from age 38-67 years). At age 56 years, genetic influences for subjective memory concern were moderately correlated with genetic influences for anxiety (r, 0.36; 95% CI, 0.18 to 0.51), negative emotionality (r, 0.51; 95% CI, 0.44-0.57), and depressive symptoms (r, 0.20; 95% CI, 0.10 to 0.29) as well as objective memory (r, -0.22; 95% CI, -0.30 to -0.14). Similar genetic correlations were seen at ages 62 and 67 years. The neuroticism PRS was associated with subjective memory concern at age 38 years (r, 0.10; 95% CI, 0.03. to 0.18) and age 67 years (r, 0.09; 95% CI, 0.01 to 0.16). Subjective memory concern was not associated with any Alzheimer disease risk measures.

Conclusions and Relevance

This cohort study found stable genetic influences underlying subjective memory concern dating back to age 38 years. Subjective memory concern had larger correlations with affect-related measures than with memory-related measures. Improving the utility of subjective memory concern as an indicator of impending cognitive decline and dementia may depend on isolating its statelike component from its traitlike component.

Subjective cognitive decline and anxious/depressive symptoms during the COVID-19 pandemic: what is the role of stress perception, stress resilience, and β-amyloid?

Background

The COVID-19 pandemic may worsen the mental health of people reporting subjective cognitive decline (SCD) and therefore their clinical prognosis. We aimed to investigate the association between the intensity of SCD and anxious/depressive symptoms during confinement and the underlying mechanisms.

Methods

Two hundred fifty cognitively unimpaired participants completed the Hospital Anxiety and Depression Scale (HADS) and SCD-Questionnaire (SCD-Q) and underwent amyloid-β positron emission tomography imaging with [18F] flutemetamol (N = 205) on average 2.4 (± 0.8) years before the COVID-19 confinement. During the confinement, participants completed the HADS, Perceived Stress Scale (PSS), Brief Resilience Scale (BRS), and an ad hoc questionnaire on worries (access to primary products, self-protection materials, economic situation) and lifestyle changes (sleep duration, sleep quality, eating habits). We investigated stress-related measurements, worries, and lifestyle changes in relation to SCD. We then conducted an analysis of covariance to investigate the association of SCD-Q with HADS scores during the confinement while controlling for pre-confinement anxiety/depression scores and demographics. Furthermore, we introduced amyloid-β positivity, PSS, and BRS in the models and performed mediation analyses to explore the mechanisms explaining the association between SCD and anxiety/depression.

Results

In the whole sample, the average SCD-Q score was 4.1 (± 4.4); 70 (28%) participants were classified as SCD, and 26 (12.7%) were amyloid-β-positive. During the confinement, participants reporting SCD showed higher PSS (p = 0.035) but not BRS scores (p = 0.65) than those that did not report SCD. No differences in worries or lifestyle changes were observed. Higher SCD-Q scores showed an association with greater anxiety/depression scores irrespective of pre-confinement anxiety/depression levels (p = 0.002). This association was not significant after introducing amyloid-β positivity and stress-related variables in the model (p = 0.069). Amyloid-β positivity and PSS were associated with greater HADS irrespective of pre-confinement anxiety/depression scores (p = 0.023; p < 0.001). The association of SCD-Q with HADS was mediated by PSS (p = 0.01).

Conclusions

Higher intensity of SCD, amyloid-β positivity, and stress perception showed independent associations with anxious/depressive symptoms during the COVID-19 confinement irrespective of pre-confinement anxiety/depression levels. The association of SCD intensity with anxiety/depression was mediated by stress perception, suggesting stress regulation as a potential intervention to reduce affective symptomatology in the SCD population in the face of stressors.

A Neuropsychological Perspective on Defining Cognitive Impairment in the Clinical Study of Alzheimer’s Disease: Towards a More Continuous Approach

The global fight against Alzheimer’s disease (AD) poses unique challenges for the field of neuropsychology. Along with the increased focus on early detection of AD pathophysiology, characterizing the earliest clinical stage of the disease has become a priority. We believe this is an important time for neuropsychology to consider how our approach to the characterization of cognitive impairment can be improved to detect subtle cognitive changes during early-stage AD. The present article aims to provide a critical examination of how we define and measure cognitive status in the context of aging and AD. First, we discuss pitfalls of current methods for defining cognitive impairment within the context of research shifting to earlier (pre)symptomatic disease stages. Next, we introduce a shift towards a more continuous approach for identifying early markers of cognitive decline and characterizing progression and discuss how this may be facilitated by novel assessment approaches. Finally, we summarize potential implications and challenges of characterizing cognitive status using a continuous approach.