Self-reported and informant-reported memory functioning and awareness in patients with mild cognitive impairment and Alzheimer´s disease

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

BACKGROUND

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Self-perceived problems in daily activities and strategy building in people with different stages of dementia

BACKGROUND

People with dementia experience severe problems in their daily lives. However, little is known about self-perceived problems in the course of dementia. The aim of our study was to assess self-perceived problems with daily activities as well as individually developed strategies of older people of different cognitive status.

METHODS

Semi-structured interviews were conducted with 25 participants (mean age 67.6 years, 56% female, 24% healthy, 28% mild dementia, 48% severe dementia). Questions addressed problems in daily activities, their occurrence and the behaviour toward them, and their developed strategies. Information was summarized quantitatively and evaluated using the chi-squared and Kruskal-Wallis tests.

RESULTS

Self-perceived problems included awareness of physical and cognitive deficits in managing daily life, disturbing factors, and lost autonomy. Increased cognitive impairment was associated with more problems in daily life, even though people with severe dementia seemed not to recognize them. The most frequently reported strategies included orderliness, doing things immediately, and the use of external aids. While healthy people and those with mild dementia developed strategies, those with severe dementia reported only few strategies.

CONCLUSION

Our findings indicate that self-perceived problems in daily life and strategy development are strongest in mild dementia, while people with more severe dementia tend to perceive no problems at all while correctly reflecting their current state of dependency. Importantly, despite memory loss during early stages of dementia, strategies are still being developed. Accordingly, strategies for daily living should be taught in early dementia to sustain an independent lifestyle.

The self and self-knowledge after frontal lobe neurosurgical lesions

BACKGROUND

Evidence suggests that damage to the frontal lobes can be associated with changes in cognitive and behavioral functioning and reduced awareness that such changes have occurred. In the current study, the Cognitive Awareness Model was used as a theoretical framework to explore knowledge of the self in people with acquired frontal lesions.

METHODS

Fifteen individuals with focal frontal lobe lesions (FFL) and their nominated informants were compared with fifteen healthy matched control-informant dyads on questionnaire measures designed to assess awareness of difficulties. Questionnaires were adapted to ensure all enabled pre- and post-injury perspectives to be gained from both patient and informant, and to allow novel exploration of awareness of deficits from a third person perspective.

RESULTS

Individuals with frontal lobe lesions showed adequate awareness of their post-surgery changes, which was substantiated by their informant report. Compared to the control group, the patient group was found to acknowledge more difficulties in current functioning. Perspective-taking ability was limited with both patients and controls being comparatively unreliable in assessing how they were perceived by others.

CONCLUSION

These results demonstrate that FLL patients are engaging in more atypical behaviors compared to healthy controls, but suggest that they are aware of and acknowledge these difficulties. The importance of obtaining multiple viewpoints when examining an individual's level of awareness and the clinical implications of this are discussed.

Measuring Memory Lapses and Their Impact on Daily Life: Results From Two Daily Diary Studies

Memory lapses (e.g., forgetting a medication) are common for most people, yet past methods of assessment relied upon retrospective reports from long recall windows. Recently, researchers have incorporated daily diary methods to capture memory lapse frequency closer to the experience in real-world environments. This study describes the utility of the Daily Memory Lapses Checklist using data from two 14-day diary studies (Combined Sample = 467; 66% women). Frequency and impact (i.e., irritation and interference) of prospective and retrospective memory lapses were assessed at both individual- and daily levels. Across studies, memory lapses occurred on more than one-third of assessment days. Retrospective lapses were reported more frequently than prospective; however, both lapses had a similar impact. The Daily Memory Lapses Checklist represents a flexible measure that separates the occurrence of a memory lapse from its impact on daily life: metrics that will enhance our understanding of daily experiences of cognitive functioning.

Utility of olfactory identification test for screening of cognitive dysfunction in community-dwelling older adults

Background

There is a need for a large-scale screening test that can be used to detect dementia in older individuals at an early stage. Olfactory identification deficits have been shown to occur in the early stages of dementia, indicating their usefulness in screening tests. This study investigated the utility of an olfactory identification test as a screening test for mild cognitive dysfunction in community-dwelling older people.

Methods

The subjects were city-dwelling individuals aged over 65 years but under 85 years who had not been diagnosed with dementia or mild cognitive impairment. The Japanese version of the Mild Cognitive Impairment Screen was used to evaluate cognitive function. Based on the results, the subjects were divided into two groups: healthy group and cognitively impaired group. Olfactory identification abilities based on the Japanese version of the University of Pennsylvania Smell Identification Test were compared between the groups.

Results

There were 182 participants in total: 77 in the healthy group and 105 in the cognitively impaired group. The mean olfactory identification test score of the cognitively impaired group was significantly lower than that of the healthy group. The cognitive impairment test score was significantly correlated with the olfactory identification test score.

Conclusions

Cross-sectional olfactory identification deficits at baseline in community-dwelling older adults reflected cognitive dysfunction. Assessing olfactory identification ability might be useful as a screening test for mild cognitive dysfunction in community-dwelling older people.

Anosognosia in Mild Cognitive Impairment: Lack of Awareness of Memory Difficulties Characterizes Prodromal Alzheimer's Disease

While anosognosia is often present in Alzheimer's disease, the degree of awareness of cognitive difficulties in the earlier stages, such as Mild Cognitive Impairment (MCI), is less clear. Using a questionnaire and Feeling-of-Knowing tasks, the aims of this study were (1) to test the hypothesis that anosognosia is present specifically in prodromal AD stage in patients that, owing to a more severe AD neuropathology, will rapidly progress to overt dementia and (2) to assess the neural bases of self-awareness for memory functioning. A group of 44 patients with amnestic MCI and a group of 29 healthy older participants (CTRL) performed two Feeling-of-Knowing tasks (episodic and semantic FOK) and responded to the Functional Memory Scale (MARS), also completed by one of their relatives. They underwent FDG-PET and structural MRI. The participants were followed clinically for 4 years. At the end of follow-up, 23 patients with MCI developed Alzheimer's disease (converters) and 21 patients still presented symptoms of MCI without progression (non-converters). The analyses focused on the data from inclusion stratified according to clinical status 4 years later (converters, non-converters, CTRL). On the episodic FOK task, converters patients overestimated their ability to later recognize unrecalled words and they showed prediction accuracy (Hamann coefficient) at the level of chance. No difficulty was observed in any group with the semantic FOK task. On the MARS, converters patients had a higher anosognosia score than non-converters patients and CTRL, which did not differ from each other. Correlations between self-awareness scores and neuroimaging data using small volume correction analyses in a priori regions of interest in converters indicated that inaccurate episodic FOK judgments was related to changes in brain areas that might support interpretation of retrieved content for judging the likelihood of recognition. For the MARS, the association between anosognosia and decreased gray matter density of the left inferior prefrontal cortex in converters might indicate poor inhibition over outdated personal knowledge. In amnestic MCI, anosognosia could be an early sign of neurodegeneration in brain areas that would support control mechanisms over memory representations.

Spouse-Appraised Memory Functioning Predicts Memory Decline Better Than Subjective Memory Complaints in Community Dwelling Older Adults at Genetic Risk for Alzheimer's Disease

Objective: Alzheimer's disease (AD) begins with subtle memory decline, years before dementia onset. The presence of subjective memory complaints (SMC) has been proposed as a marker of preclinical AD. However, recent evidence has demonstrated early and progressive loss of awareness of memory difficulties in non-demented older adults harboring AD pathology. We investigated the respective contributions of SMC and spouse-appraised memory functioning (SAM) to predict memory decline in a large cohort of community dwelling older adults. Methods: The Wisconsin Longitudinal Study collected cognitive data from a community-based cohort of 3,583 participants in both 2005 and 2011. The participant and the participant's spouse were each asked to rate the participant's memory functioning using a Likert scale. We predicted change in objective episodic memory with models including baseline SMC, baseline SAM, or both SMC and SAM. We also evaluated an awareness index (SMC minus SAM). We then tested the interaction between Apolipoprotein E (APOE ε4) carrier status and SMC/SAM to evaluate whether the effects were driven by individuals at-risk for AD pathology. Results: In separate models, SMC (-0.081 ± 0.036, p = 0.025) and SAM (-0.084 ± 0.278, p = 0.003) were both associated with memory decline over ~6 years. However, the AI was not significantly associated with memory decline (0.031 ± 0.024, p = 0.19). When both predictors were included in the same model, SAM (-0.074 ± 0.03, p = 0.0092) was associated with memory decline, while SMC was not significant (-0.061 ± 0.04, p = 0.99). The association between SAM and memory decline was stronger in the APOE ε4 carriers than in the non-carriers (APOE-by-SAM interaction: F = 6.07; p = 0.002), and follow up analyses revealed that SAM was particularly predictive of decline only for APOE ε4 carriers. The association between SMC and memory decline was independent of APOE ε4 carrier status (APOE-by-SMC interaction: F = 2.29; p = 0.13). Conclusions: Spouse-appraised memory functioning was more predictive of memory decline than SMC or an awareness index, particularly in APOE ε4 carriers, who are at increased risk for AD pathology.

Alexithymia in Alzheimer's Disease

Alexithymia is widely recognized as the inability to identify and express emotions. It is a construct which consists of four cognitive traits such as difficulty in identifying feelings, describing feelings to others, externally oriented thinking, and limited imaginative capacity. Several studies have linked alexithymia to cognitive functioning, observing greater alexithymia scores associated with poorer cognitive abilities. Despite Alzheimer's disease (AD) being a neurodegenerative pathology characterized by cognitive troubles from the early stages, associated to behavioral and emotional disturbances, very few investigations have studied the alexithymia in AD. These studies have shown that alexithymia scores-assessed with Toronto Alexithymia Scale (TAS)-were greater in AD patients than healthy participants. The objective of the study was to investigate if the alexithymia was present in patients with mild AD. We hypothesized that the AD group would show more alexithymia features than the control group. We evaluated 54 subjects, including 27 patients diagnosed with mild AD and 27 normal healthy controls, using the Shalling Sifneos Psychosomatic Scale (SSPS-R) and a neuropsychological test battery. Using non-parametric statistical analyses-Wilcoxon and Mann-Whitney U tests-we observed that the SSPS-R scores were similar in the AD and control groups. All participants showed SSPS-R scores below to 10 points, which means no-alexithymia. We did not find significant correlations between SSPS-R scores and cognitive variables in both groups (p > 0.22), but we observed a negative association between name abilities and alexithymia, but it does not reach to significance (p = 0.07). However, a significant correlation between SSPS-R score and mood state, assessed using Zerssen Rating Scale, was found in both groups (p = 0.01). Because we did not find a significant difference in the alexithymia assessment between both subject groups, pot hoc analyses were computed for each item of the SSPS-R. We made comparisons of alexithymic responses percentages in each SSPS-R item between AD and control groups, using Fisher's test. We observed that AD patients produced more alexithymic responses in some items of SSPS-R test than the control group, particularly about difficulties to find the words to describe feelings, as well as difficulties of imagination capacity and externally oriented thinking. The present results do not confirm our hypothesis and they do not support the results of previous studies revealing great alexithymia in AD.

Association Between Proxy- or Self-Reported Cognitive Decline and Cognitive Performance in Memory Clinic Visitors

BACKGROUND

It is uncertain whether self- and proxy-reported cognitive decline in older adults reflect an actual objective cognitive dysfunction in the clinical sense, and if these are predictive for developing dementia.

OBJECTIVE

The aim of the present study is to investigate the cross-sectional and longitudinal relation between subjective cognitive decline and objective cognitive performance, depressive symptoms, and to determine the predictive value for development of dementia.

METHODS

We included 405 patients without dementia at first visit from the Maastricht memory clinic participating in a longitudinal cohort study. Subjective cognitive decline was measured using a self- and proxy-report questionnaire. All patients underwent a standardized neuropsychological assessment. Follow-up assessments were performed yearly for three consecutive years, and once after five years.

RESULTS

Subjective cognitive decline was associated with lower cognitive performance and more depressive symptoms. When comparing self- (n = 342, 84%) and proxy-reported decline (n = 110, 27%), it was shown that proxy reports were associated with a more widespread pattern of lower cognitive performance. In participants without cognitive impairment proxy-reported decline was not associated with depressive symptoms. In contrast, self-reported decline was associated with a stable course of depressive symptoms at follow-up. Proxy-reported cognitive decline (HR = 1.76, 95% CI = 1.12- 2.78), and mutual complaints (HR = 1.73, CI:1.09- 2.76) predicted incident dementia while self-reported decline did not reach statistical significance (HR = 1.26, 95% CI = 0.65- 2.43).

CONCLUSION

Proxy-reported cognitive decline was consistently associated with lower cognitive performance and conversion to dementia over 5 years. Self-reported cognitive decline in patients without cognitive impairment might indicate underlying depressive symptoms and thus deserve clinical attention as well.

Increasing Inaccuracy of Self-Reported Subjective Cognitive Complaints Over 24 Months in Empirically Derived Subtypes of Mild Cognitive Impairment

OBJECTIVES

Although subjective cognitive complaints (SCC) are an integral component of the diagnostic criteria for mild cognitive impairment (MCI), previous findings indicate they may not accurately reflect cognitive ability. Within the Alzheimer's Disease Neuroimaging Initiative, we investigated longitudinal change in the discrepancy between self- and informant-reported SCC across empirically derived subtypes of MCI and normal control (NC) participants.

METHODS

Data were obtained for 353 MCI participants and 122 "robust" NC participants. Participants were classified into three subtypes at baseline via cluster analysis: amnestic MCI, mixed MCI, and cluster-derived normal (CDN), a presumptive false-positive group who performed within normal limits on neuropsychological testing. SCC at baseline and two annual follow-up visits were assessed via the Everyday Cognition Questionnaire (ECog), and discrepancy scores between self- and informant-report were calculated. Analysis of change was conducted using analysis of covariance.

RESULTS

The amnestic and mixed MCI subtypes demonstrated increasing ECog discrepancy scores over time. This was driven by an increase in informant-reported SCC, which corresponded to participants' objective cognitive decline, despite stable self-reported SCC. Increasing unawareness was associated with cerebrospinal fluid Alzheimer's disease biomarker positivity and progression to Alzheimer's disease. In contrast, CDN and NC groups over-reported cognitive difficulty and demonstrated normal cognition at all time points.

CONCLUSIONS

MCI participants' discrepancy scores indicate progressive underappreciation of their evolving cognitive deficits. Consistent over-reporting in the CDN and NC groups despite normal objective cognition suggests that self-reported SCC do not predict impending cognitive decline. Results demonstrate that self-reported SCC become increasingly misleading as objective cognitive impairment becomes more pronounced. (JINS, 2018, 24, 842-853).

An Initial Study of Alexithymia and Its Relationship With Cognitive Abilities Among Mild Cognitive Impairment, Mild Alzheimer's Disease, and Healthy Volunteers

The present study examined the degree to which alexithymia is greater in mild Alzheimer's disease (AD) and mild cognitive impairment (MCI) relative to healthy volunteers (healthy comparison [HC]), and investigated relationships between alexithymia and cognition. Eighty-five participants (MCI = 30, AD = 21, HC = 34) underwent a comprehensive neuropsychological examination and completed the 20-item Toronto Alexithymia Scale (TAS-20). Relative to HC, MCI and AD reported greater alexithymia total scores and higher scores on the TAS factor difficulty in identifying feelings (DIF). The remaining two factors, difficulty in describing feelings (DDF) and externally oriented thinking showed no significant group differences. In MCI, TAS-20 and DIF were negatively correlated with working and long-term verbal memory. In AD, TAS-20 was negatively correlated with general cognition, attention, memory, and visual spatial constructive and executive abilities. Also in AD, DIF was negatively correlated with general cognition, memory, and executive abilities. The correlation between DIF and long-term verbal memory in both MCI and AD suggests a potential common mechanism for alexithymia in these neurocognitive disorders. Declines in verbal memory may hinder a patient's ability to recall an association between a given sensation and the episodic experience of that sensation, thus leading to difficulty identifying feelings, as measured by the DIF factor of the TAS-20.

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.

Integrating the Constructs of Anosognosia and Metacognition: a Review of Recent Findings in Dementia

The current review integrates recent findings regarding the construct of self-awareness in dementia from both clinical and cognitive perspectives. We present the predominant theoretical models of awareness and summarize both traditional and emerging approaches to assessing awareness from clinical and meta-cognitive perspectives. In this review, we focus primarily on findings from recent studies in anosognosia and meta-cognition in the context of neurodegenerative disease with special emphasis on Alzheimer's disease and frontotemporal dementia. Emerging trends in the study of awareness, including examination of the longitudinal course of anosognosia, and investigation of the neural substrates underlying meta-cognitive abilities are addressed. Finally, the practical importance of studying and assessing awareness from both theoretical and clinical angles is emphasized.

Awareness, apathy, and depression in Alzheimer's disease and mild cognitive impairment

INTRODUCTION

Results from studies on awareness disorders in Alzheimer's disease (AD) are controversial because the methodologies, the "objects" of awareness, and the patients' pathologic stage all vary. Our study aimed to compare scores and correlates of awareness according to the stage of the disease and the assessment method.

METHODS

We compared 20 mild AD patients to 20 mild cognitive impairment (MCI) patients, using the Patient Competency Rating Scale (PCRS; patient vs. caregiver report) and the Self-Consciousness Scale (rating scale). All patients underwent cognitive, psycho-affective and behavioral assessments (global cognition, executive functions, episodic memory, anxiety-depression, and apathy measures).

RESULTS

Groups were matched for age, education, and gender. They were comparable on the depression, anxiety, apathy and awareness scales (ps > .05), and differed for all cognitive variables (p < .05). Using the median split approach, greater apathy and lower depression were associated with poorer awareness on the Self-Consciousness Scale (respectively: odds ratio [OR] = 4.8, p = .03; OR = 4.84, p = .04), and the PCRS (only apathy: OR = 9.3, p = .003). Greater apathy plus lower depression were associated with poorer awareness in both scales (PCRS: OR = 40.5, p = .005; Self-consciousness scale: OR = 28, p = .012).

CONCLUSION

These results evidence comparable awareness between AD and MCI patients. The correlates were more affective and behavioral than cognitive, independently from assessment method.