Subjective Cognitive Decline Is More Accurate When Metamemory Is Better

Subjective cognitive decline: Memory complaints, cognitive awareness, and metacognition

Cognitive complaints are common in elderly subjects and are a frequent reason for referral to memory clinics. If the complaints are not associated with objective cognitive impairment, the condition is labelled subjective cognitive decline (SCD). SCD is often considered as a stage antedating objective impairment, and an at-risk condition for subsequent dementia. Recent large-scale studies indicate that a significantly increased risk of clinical progression in subjects with SCD is associated with positivity for Alzheimer's disease (AD) biomarkers, a finding supporting the notion that SCD can be due to different mechanisms not associated with neurodegeneration, including functional cognitive disorders. In this paper we present a selective review of research on the relations among SCD, cognitive awareness, and metacognitive abilities. We propose that longitudinal studies of metacognitive efficiency in SCD may provide useful cues about the risk of progression to dementia and the possible presence of a functional cognitive disorder, with different implications for the management of this prevalent aging-related condition. HIGHLIGHTS: Subjective cognitive decline (SCD), a common cause of referral to memory clinics, can be due to multiple conditions. The predictive value of SCD for progression to Alzheimer's disease (AD) dementia is high in association with AD biomarker positivity. The awareness of cognitive decline is the mechanism responsible for the emergence of SCD and metacognition is the underlying neuropsychological function. The awareness of cognitive decline in clinical patients is usually assessed comparing an informant rating to the patient self-assessment, a method that can be affected by informant bias. While there is strong evidence that awareness starts to decline with the onset of objective cognitive impairment, progressively leading to the anosognosia of AD, the status of metacognitive efficiency in SCD needs to be further investigated. Quantitative, performance-based indexes of metacognitive efficiency may contribute both to the assessment of progression risk and to the management of subjects with functional cognitive disorders.

Confronting Alzheimer's Disease Risk in Women: A Feasibility Study of Memory Screening as Part of the Annual Gynecological Well-Woman Visit

Objective: Routine health care visits offer the opportunity to screen older adults for symptoms of Alzheimer's disease (AD). Many women see their gynecologist as their primary health care provider. Given this unique relationship, the Women's Preventive Services Initiative and the American College of Obstetrics and Gynecology advocate for integrated care of women at all ages. It is well-established that women are at increased risk for AD, and memory screening of older women should be paramount in this effort. Research is needed to determine the feasibility and value of memory screening among older women at the well-woman visit. Materials and Methods: Women aged 60 and above completed a 5-item subjective memory screener at their well-woman visit at the Columbia University Integrated Women's Health Program. Women who endorsed any item were considered to have a positive screen and were given the option to pursue clinical evaluation. Rates of positive screens, item endorsement, and referral preferences were examined. Results: Of the 530 women approached, 521 agreed to complete the screener. Of those, 17.5% (n = 91) were classified as positive. The most frequently endorsed item was difficulty with memory or thinking compared with others the same age. Among women with positive screens, 57.5% were interested in pursuing clinical referrals to a memory specialist. Conclusion: Results support the feasibility and potential value of including subjective memory screening as part of a comprehensive well-woman program. Early identification of memory loss will enable investigation into the cause of memory symptoms and longitudinal monitoring of cognitive change.

Investigating the Effects of Discrimination Experiences on Everyday Metamemory Accuracy

OBJECTIVES

Lifetime and daily experiences of discrimination contribute to impaired performance on cognitive assessments. However, the underlying mechanism by which discrimination negatively affects cognition is unclear. Recent research investigating stress-induced impairment of metamemory may address the relationship between discrimination experiences and cognitive impairment.

METHODS

The aim of this study was to determine the relationship of lifetime and daily experiences of discrimination, daily affect balance, baseline objective cognitive performance, and sociodemographic variables (age, race, ethnicity, and sex) with metamemory accuracy across the lifespan (ages 20-75). Impaired metamemory accuracy was defined by the number of subjective cognitive complaints. Diary data from the Midlife in the United States (MIDUS Refresher 1) Daily Diary Project (N = 782) was used for these analyses.

RESULTS

Results from linear mixed model analyses showed significant within-person effects of daily discrimination, where people who reported more daily discrimination also reported lower metamemory accuracy, and daily affect balance, where people who reported very negative affect also reported lower metamemory accuracy. Additionally, linear mixed model analyses revealed significant between-person effects of race on metamemory accuracy, with individuals from minoritized racial groups generally reporting poorer metamemory accuracy. Daily discrimination experiences also interacted with other variables in predicting day-to-day metamemory accuracy.

DISCUSSION

These findings add to our understanding of how psychosocial stress in the form of daily discrimination experiences may impair metamemory processes contributing to increased subjective cognitive complaints. Future research should consider the contribution of daily experiences of discrimination across the lifespan to poor cognitive outcomes in later life.

Subjective cognitive decline in healthy older adults is associated with altered processing of negative versus positive feedback in a probabilistic learning task

Older adults who worry about their own cognitive capabilities declining, but who do not show evidence of actual cognitive decline in neuropsychological tests, are at an increased risk of being diagnosed with dementia at a later time. Since neural markers may be more sensitive to early stages of cognitive decline, in the present study we examined whether event-related potential responses of feedback processing, elicited in a probabilistic learning task, differ between healthy older adults recruited from the community, who either did (subjective cognitive decline/SCD-group) or did not report (No-SCD group) worry about their own cognition declining beyond the normal age-related development. In the absence of group differences in learning from emotionally charged feedback in the probabilistic learning task, the amplitude of the feedback-related negativity (FRN) varied with feedback valence differently in the two groups: In the No-SCD group, the FRN was larger for positive than negative feedback, while in the SCD group, FRN amplitude did not differ between positive and negative feedback. The P3b was enhanced for negative feedback in both groups, and group differences in P3b amplitude were not significant. Altered sensitivity in neural processing of negative versus positive feedback may be a marker of SCD.

Subjective Complaints are Similar in Subjective Cognitive Decline and Early-Stage Alzheimer's Disease when Assessed in a Memory Clinic Setting

BACKGROUND

Subjective cognitive complaints are generally poorly associated with objective memory functioning in older persons. Subjective cognitive decline (SCD) is a key feature in SCD and amnestic mild cognitive impairment (aMCI) which both can represent early Alzheimer's disease (AD). The aim of this study was to assess how memory clinic patients with SCD, MCI and mild AD dementia scored on 3 different complaint measures and if the format of assessment had an impact on the association with cognitive functioning, age, and depressive symptoms.

METHODS

We included 17 SCD patients, 17 aMCI patients, 17 patients with mild AD, and 30 controls. Complaints were assessed with the Cognitive Change Index (CCI), the Subjective Memory Complaints (SMC) scale, and the Memory Complaint Questionnaire (MAC-Q).

RESULTS

There were no significant differences between the total scores in the patient groups on the questionnaires. However, significant differences were found in the number of patients classified with impairment when using the CCI, the SMC, and the MAC-Q. Scores on all questionnaires were significantly associated with depressive symptoms, and significant associations with age, gender, and Addenbrookes Cognitive Examination score were found for the SMC. In patients with cognitive dysfunction, lower memory awareness significantly predicted fewer cognitive complaints.

CONCLUSIONS

SCD patients in a memory clinic setting report the same degree of cognitive impairment as patients with aMCI and mild dementia, and in a hospital-based cohort we extend previous findings from healthy controls, that definition of SCD may depend on the format of assessment.

Association of Subjective Cognitive Decline With Progression to Dementia in a Cognitively Unimpaired Multiracial Community Sample

BACKGROUND AND OBJECTIVES

This prospective study seeks to examine the utility of subjective cognitive decline (SCD) as a marker of future progression to dementia in a community-based cohort of non-Latinx White, non-Latinx Black, and Latinx individuals. Debate surrounds the utility of SCD, the subjective perception of decline in one's cognition before such impairment is evident in traditional neuropsychological assessments, as an early indicator of impending Alzheimer disease. Unfortunately, most studies examining SCD have been conducted in non-Latinx White samples and commonly exclude groups of individuals shown to be most vulnerable to dementia.

METHODS

Participants were enrolled into this cohort study from the Washington Heights-Inwood Columbia Aging Project if they were cognitively unimpaired, had baseline measurement of SCD, and self-identified as non-Latinx White, non-Latinx Black, or Latinx. SCD was measured as a continuous sum of 10 items assessing cognitive complaints. Competing risk models tested the main effects of baseline SCD on progression to dementia. Models were adjusted for age, sex/gender, years of education, medical comorbidity burden, enrollment cohort, and baseline memory test performance with death jointly modelled as a function of race/ethnicity.

RESULTS

A total of 4,043 (1,063 non-Latinx White, 1,267 non-Latinx Black, and 1,713 Latinx) participants were selected for this study with a mean age of 75 years, 67% women, and with a mean follow-up of 5 years. Higher baseline SCD was associated with increased rates of incident dementia over time in the full sample (hazard ratio [HR] 1.085, CI 1.047-1.125, p < 0.001) and within Latinx (HR 1.084, CI 1.039-1.130, p < 0.001) and non-Latinx Black individuals (HR 1.099, CI 1.012-1.194, p = 0.024).

DISCUSSION

Overall results of this study support SCD as a prodromal marker of dementia in a multiracial community sample, and in Latinx and non-Latinx Black individuals in particular. Because models examining the risk of dementia were adjusted for baseline memory test performance, the results support the idea that SCD, a subjective reflection of one's own current cognitive functioning, contributes information above and beyond standard memory testing. Current findings highlight the importance of carefully evaluating any memory concerns raised by older adults during routine visits and underscore the potential utility of screening older adults for SCD.

Examining the Role of Aging Perceptions in Subjective Cognitive Decline

OBJECTIVE

While subjective cognitive decline (SCD) is gaining ground as a "preclinical" risk state for Alzheimer disease, its utility depends on our understanding of the factors linked to SCD. Rarely examined sociocultural factors including perceptions of aging may relate to the subjective experience of cognitive aging. Identifying such associations will help to refine the utility of SCD as an early marker of AD while setting the stage for addressing modifiable factors contributing to SCD.

METHODS

The study consisted of N=136 participants (68% female; 73% White; 22% Black race, age mean =74.72; education mean =16.01). Questionnaires assessed SCD, depressive symptoms, and age perceptions (essentialist aging beliefs, subjective age, age group identification, and explicit/implicit age stereotypes). Cognitive functioning was measured with a semantic interference and learning task.

RESULTS

SCD was correlated with essentialist aging beliefs, age identification, and depressive symptoms [ rrange =0.18 to 0.22, Prange =0.009 to 0.02, confidence interval (CI) range =0.00-0.39]. Essentialist aging beliefs were correlated with subjective age and age group identification ( rrange =0.22 to 0.42, Prange <0.001 to 0.003, CI range =0.08-0.57). Both age group identification and essentialism were correlated with depressive symptoms ( rrange =0.22, Prange =0.009 to 0.01, CI range =0.04-0.39). In the adjusted regression model including depressive symptoms, age perceptions, and SCD, only SCD was associated with cognition ( b =-0.31, P <0.001).

CONCLUSION

Although correlated with SCD, perceptions of aging do not explain the relationship between SCD and performance on a sensitive cognitive test among older adults.