Longitudinal patterns of unawareness of memory deficits in mild Alzheimer's disease

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.

Awareness of Cognitive Decline in Patients With Alzheimer's Disease: A Systematic Review and Meta-Analysis

Background: Identifying a poor degree of awareness of cognitive decline (ACD) could represent an early indicator of Alzheimer's disease (AD). Objectives: (1) to understand whether there is evidence of poor ACD in the pre-dementia stages of AD; (2) to summarize the main findings obtained investigating ACD in AD; (3) to propose a conceptual framework. Data Sources: We searched Scopus, Pubmed, and the reference lists for studies published up to August 2020. Original research articles must report a measure of ACD and included individuals with AD dementia, or prodromal AD (or MCI), or being at risk for AD. Data Synthesis: All studies covering preclinical, prodromal, and AD dementia were systematically reviewed. We intended to perform a meta-analysis of empirical studies on preclinical AD or prodromal AD (or MCI), to compare ACD between clinical groups. Due to the paucity of literature on preclinical AD, meta-analysis was only possible for prodromal AD (or MCI) studies. Results: We systematically reviewed 283 articles, and conducted a meta-analysis of 18 articles on prodromal AD (or MCI), showing that ACD was not significantly different between patients with amnestic and non-amnestic MCI (SMD = 0.09, p = 0.574); ACD was significantly poorer in amnestic MCI (SMD = -0.56, p = 0.001) and mild AD (SMD = -1.39, p < 0.001) than in controls; ACD was also significantly poorer in mild AD than in amnestic MCI (SMD = -0.75, p < 0.001), as well as poorer than in non-amnestic MCI (SMD = -1.00, p < 0.001). We also discuss key findings on ACD in AD, such as its neural and cognitive correlates. Conclusions and Implications: We propose that patients may be complaining of their initial subtle cognitive changes, but ACD would soon start to decrease. The individual would show mild anosognosia in the MCI stage, and severe anosognosia in dementia. The evaluation of ACD (comparing self-report to cognitive scores or to informant-report) could be useful to guide the clinician toward a timely diagnosis, and in trials targeting early-stage AD.

Patterns of discrepancies in different objects of awareness in mild and moderate Alzheimer's disease

Objectives: Awareness is considered a heterogeneous and non-linear phenomenon in dementia. We aim to investigate patterns of change of different domains of awareness (awareness of cognitive functioning and health condition, activities of daily living, emotional state, social functioning, and relationships) in people with mild and moderate Alzheimer's disease (AD) and aspects related to each domain.Method: Cross-sectional assessment of dyads of people with AD (PwAD) and caregivers (n = 128; CDR1 = 74, CDR2 = 54). PwAD completed assessments about quality of life, cognition and their awareness of disease. Caregivers provided information about PwAD and received quality of life and burden of care assessments.Results: Mild AD group showed a mildly impaired awareness (n = 40; 54.05%), while moderate AD group, showed higher presence of moderately impaired awareness (n = 22; 40.74%). There was a significant difference between groups in awareness of cognitive functioning and health condition (p < 0.004), functional activity impairments (p < 0.001) and total score of awareness (p < 0.01). Conversely, awareness of emotional state (p = 0.22) and of social functioning and relationship (p = 0.44) presented no significant difference between groups. Unawareness of functional activity impairments showed higher discrepancy scores between PwAD and caregivers in both groups.Conclusions: Significant differences were found only in patterns of discrepancies in awareness of cognitive functioning and health condition, of ADL and socio-emotional functioning. Different factors are related to different domains in mild and moderate group, reinforcing the heterogeneity of awareness in dementia. ADL deficits have an important role in awareness phenomenon, independent of the severity of disease.

Evolution of anosognosia in alzheimer's disease and its relationship to amyloid

OBJECTIVE

Unawareness, or anosognosia, of memory deficits is a challenging manifestation of Alzheimer's disease (AD) that adversely affects a patient's safety and decision-making. However, there is a lack of consensus regarding the presence, as well as the evolution, of altered awareness of memory function across the preclinical and prodromal stages of AD. Here, we aimed to characterize change in awareness of memory abilities and its relationship to beta-amyloid (Aβ) burden in a large cohort (N = 1,070) of individuals across the disease spectrum.

METHODS

Memory awareness was longitudinally assessed (average number of visits = 4.3) and operationalized using the discrepancy between mean participant and partner report on the Everyday Cognition scale (memory domain). Aβ deposition was measured at baseline using [18F]florbetapir positron emission tomographic imaging.

RESULTS

Aβ predicted longitudinal changes in memory awareness, such that awareness decreased faster in participants with increased Aβ burden. Aβ and clinical group interacted to predict change in memory awareness, demonstrating the strongest effect in dementia participants, but could also be found in the cognitively normal (CN) participants. In a subset of CN participants who progressed to mild cognitive impairment (MCI), heightened memory awareness was observed up to 1.6 years before MCI diagnosis, with memory awareness declining until the time of progression to MCI (-0.08 discrepant-points/yr). In a subset of MCI participants who progressed to dementia, awareness was low initially and continued to decline (-0.23 discrepant-points/yr), reaching anosognosia 3.2 years before dementia onset.

INTERPRETATION

Aβ burden is associated with a progressive decrease in self-awareness of memory deficits, reaching anosognosia approximately 3 years before dementia diagnosis. ANN NEUROL 2020;87:267-280.

"What" and "How": A New Perspective for Understanding Unawareness in Alzheimer's Disease Through a Combination of Two Perspectives

OBJECTIVES

Assessments of unawareness in Alzheimer's disease mainly focus on the objects (the "what") of unawareness. A recent person-centered approach proposes to also assess the processes (the "how"). The present study combines 2 approaches to understand this heterogeneity in assessments of unawareness.

METHOD

We recruited 46 participants from 8 nursing homes. They underwent a semi-structured interview and were assessed using a prediction-performance paradigm. Spearman correlations were calculated, and generalized additive models were established.

RESULTS

The 2 approaches are associated through cognitive deficits, confrontation with difficulties and identity changes. Objects (the what), mechanisms, and modes of expression (the how) explain at least 29.6% of the variance of unawareness.

CONCLUSIONS

Unawareness is more than simply being unaware of something; it is a synergy between the objects and processes of arousal and expression. Moreover, unawareness extends beyond the disease to include the self. Considering the entire person seems to be necessary.

Antecedents and consequences of unawareness of memory impairment in dementia

OBJECTIVE

To assess the prevalence, antecedents, and consequences of unawareness of memory impairment in dementia.

METHOD

Persons (n = 1,862) from a geographically defined community without dementia at enrollment subsequently underwent clinical classification (248 with dementia, 611 with mild cognitive impairment, 1,003 with no cognitive impairment), memory testing, and self-appraisal of memory. Memory performance was regressed on self-appraised memory, and the residuals served as an index of memory awareness. After clinical classification, participants completed brief cognitive testing at 3-year intervals for up to 15 years.

RESULTS

When unawareness was defined as a score at or below thresholds ranging from the 15th to 25th percentiles, it was more common in dementia (67%-83%) and mild cognitive impairment (15%-33%) than in no cognitive impairment (2%-6%; all p < .001). A continuous measure of awareness (M = 0.00, SD = 0.61) was reduced by 0.37-unit in mild cognitive impairment (SE = 0.04, p < .001) and 1.04-unit in dementia (SE = 0.06), p < .001) compared with those without cognitive impairment, and these associations were weaker in Black persons than White persons (estimate for dementia by race = 0.37, SE = 0.12, p = .003; estimate for mild cognitive impairment by race = 0.30, SE = 0.08, p < .001). Higher premorbid neuroticism was associated with better memory awareness in dementia. Higher memory awareness was not related to mortality in mild cognitive impairment or dementia but had a marginal association with slower cognitive decline in mild cognitive impairment.

CONCLUSIONS

Unawareness of memory impairment is a common manifestation of dementia, particularly in White persons, but is not strongly related to adverse disease outcomes. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Subjective Age and Dementia

OBJECTIVE

Existing evidence indicates that a younger subjective age is a marker of successful aging, including better health and cognition. Building upon this evidence, it is likely that individuals with dementia might feel older. However, subjective evaluation of age might not be affected by dementia because these individuals tend to be anosognosic and report positive health-related quality of life.

METHODS

Data from two cross-sectional samples from France and the United States were used to compare the subjective age ratings of individuals with and without dementia.

RESULTS

Results from both samples revealed that individuals with dementia felt younger than their age but did not differ from the controls, even after controlling for sex, chronological age, education, and self-rated health.

CONCLUSION

The present study suggests that there are no large differences in the subjective experience of age between healthy individuals and those with dementia.

Temporal course and pathologic basis of unawareness of memory loss in dementia

OBJECTIVE

To characterize the natural history and neuropathologic basis of unawareness of memory loss in late-life dementia.

METHODS

Analyses are based on 2,092 older persons from 3 longitudinal clinical-pathologic cohort studies who had no memory or cognitive impairment at baseline. Annual evaluations included clinical classification of dementia plus self-rating and performance testing of memory. At death, there was a uniform neuropathologic examination to quantify 7 dementia-related pathologies.

RESULTS

In the full group, memory ratings were modestly correlated with memory performance (intercepts r = 0.26, p < 0.001; slopes r = 0.23, p < 001) and so we regressed each person's memory performance on their memory ratings, and the residuals provided longitudinal indicators of memory awareness. In a subset of 239 persons who developed dementia, episodic memory awareness was stable until a mean of 2.6 years before dementia onset (95% credible interval -2.7, -1.6); thereafter, memory awareness declined rapidly (mean annual change -0.32, 95% credible interval -0.37, -0.28). Older age at baseline was associated with later onset of memory unawareness. In a subset of 385 persons who died and underwent neuropathologic examination, transactive response DNA-binding protein 43 (TDP-43) pathology, tau tangles, and gross cerebral infarcts were related to decline in memory awareness. In the absence of these pathologies, no decline in memory awareness was evident. Results were similar in subgroups with and without dementia.

CONCLUSIONS

Awareness of memory impairment typically begins to decline about 2-3 years before dementia onset and is associated with postmortem evidence of TDP-43 pathology, tangles, and gross cerebral infarcts.

Longitudinal changes in awareness over 36 months in patients with mild Alzheimer's disease

BACKGROUND

Longitudinal changes in awareness in dementia have been studied with short follow-up time and mostly in small patient groups (including patients with moderate dementia). We investigated awareness in patients with mild Alzheimer's disease (AD) over 36 months and studied if a decline in awareness was associated with decline in cognition and increase in neuropsychiatric symptoms.

METHODS

Awareness was measured on a categorical scale in 95 AD patients (age ≥50 years, Mini-Mental State Examination (MMSE) score ≥20). Awareness was rated at three time points (follow-up at 12 and 36 months) where MMSE, Neuropsychiatric Inventory (NPI-Q), and Cornell scale for Depression in Dementia also were applied.

RESULTS

At 12 months, 26% had lower awareness rating as compared to baseline and at 36 months lower awareness ratings were found in 39%. At both visits, 16% had higher awareness rating as compared to baseline. Patients with lower awareness at 36 months as compared to baseline had a more rapid increase in NPI-Q score (p = 0.002) over 36 months as compared to patients with stable or improved awareness over 36 months. A more rapid decline in MMSE score was observed for patients with lower awareness at 36 months (as compared to baseline) but only when compared to patients in whom awareness improved over time.

CONCLUSIONS

The results show essentially no clear relationship between cognitive decline over three years and awareness. In some cases, awareness remained stable or even improved despite significant cognitive decline. In the subgroup where awareness declined over time, overall ratings of neuropsychiatric symptoms declined more rapidly than in the remaining patients.

Consciência do déficit na doença de Alzheimer: diferenças entre os domínios cognitivo e funcional

OBJETIVOS: Revisar sistematicamente desenhos de estudo, instrumentos de avaliação e fatores relacionados ao comprometimento dos domínios cognitivo e funcional da consciência do déficit em pessoas com doença de Alzheimer (DA). MÉTODO: Pesquisa nas bases de dados PubMed e ISI de estudos sobre consciência do déficit na DA publicados entre 2008 e 2013. As palavras-chave utilizadas foram: "dementia", "Alzheimer", "awareness", "awareness of memory" e "awareness of functioning", "deficits", "cognition". RESULTADOS: Os 10 artigos selecionados utilizaram os conceitos "falta de consciência do déficit", "anosognosia", "insight", "falta de consciência das dificuldades cognitivas" e "consciência limitada das deficiências". A etiologia do comprometimento da consciência do déficit foi relacionada a fatores biológicos como gravidade clínica da doença, associações neuroanatômicas, alterações neuropsiquiátricas e fatores psicológicos e sociais. O desenho de estudo mais utilizado foi o corte transversal. No domínio cognitivo, a memória e as funções executivas foram as duas principais funções investigadas. No domínio funcional, foram encontradas associações com a disfunção executiva, declínio da interação social, depressão e a influência do desempenho ocupacional. CONCLUSÕES: As distintas hipóteses etiológicas, a operacionalização variável do conceito e a falta de instrumentos de avaliação padronizados impossibilitam a obtenção de resultados homogêneos. Essas dificuldades comprometem a compreensão e a investigação dos domínios cognitivo e funcional.

Utility of the AD8 as a self-rating tool for cognitive impairment in an Asian population

BACKGROUND

AD8 is a brief informant interview used to detect early cognitive change. This study evaluated the diagnostic performance of the participant-rated AD8 (p-AD8) in a predominantly Chinese population.

METHODS

Data on demographics, clinical, and cognitive features were collected from 73 participants with no cognitive impairment (NCI), 27 participants with mild cognitive impairments, and 78 participants with Alzheimer's disease-informant dyads. Agreement and discriminative properties of p-AD8 were assessed.

RESULTS

AD8 scores were associated with dementia severity. Participant and informant AD8 scores were moderately correlated within dementia dyads. The p-AD8 showed good diagnostic performance in differentiating between participants with NCI and participants with cognitive impairment (sensitivity = 85.0%, specificity = 74.0%, and area under the curve = 0.80), with a cutoff score of ≥1. Combination of impairment in Mini-Mental State Examination and p-AD8 is more useful in detecting cognitive impairment than using the AD8 alone.

CONCLUSION

Within a transcultural setting, the p-AD8 demonstrated good discriminative validity and can be used to gain a preliminary understanding of an individual's cognitive status.

Anosognosia and depression in patients with Alzheimer's dementia

Anosognosia refers to impaired awareness of patients to realize deficits related to a disorder and is a common symptom of dementia. Anosognosia has far-reaching consequences for diagnosis and treatment and is probably associated with unfavorable prognosis. This study examined the relationship between anosognosia and depression in patients with Alzheimer's dementia (AD). Assessment included interviews of patients and their caregivers. Depressive symptoms were evaluated with observer and self-rating instruments: the Geriatric Depression Scale (GDS), and the "mood" subscale of the Nurses Observation Scale for geriatric patients (NOSGER). Anosognosia was evaluated with the Anosognosia Questionnaire for Dementia (AQ-D). For the evaluation of behavioral and neuropsychological symptoms in dementia and the caregiver burden, the neuropsychiatric inventory (NPI) and the Cares of older People in Europe (COPE) Index were administered. A total of 47 patients were enrolled in the study at the department's geriatric psychiatry outpatient clinic. A considerable discrepancy was found between observer- and self-ratings of depressive symptoms. In 74.5% of the participants, caregiver ratings indicated secondary symptoms of depression as opposed to patient ratings. Thus, in AD, anosognosia may affect not only deficits in cognition and everyday functioning but also affective symptoms ("affective anosognosia"). Caregiver rating therefore is particularly important when assessing mood changes in AD patients.

Consciência da doença na demência do tipo Alzheimer: uma revisão sistemática de estudos longitudinais

OBJETIVOS: Avaliar as definições, métodos de avaliação e hipóteses etiológicas utilizadas em estudos longitudinais sobre consciência da doença na demência do tipo Alzheimer. MÉTODO: Pesquisa, nas bases de dados Medline, ISI, Lilacs e SciELO, de estudos longitudinais sobre consciência da doença na demência do tipo Alzheimer entre 1999 e 2009. As palavras-chave utilizadas foram: "Alzheimer", "dementia", "anosognosia", "awareness of deficit", "awareness of disease", "insight" e "longitudinal study". Os artigos examinados foram classificados conforme as hipóteses etiológicas encontradas. RESULTADOS: Os nove artigos selecionados foram divididos em duas áreas: hipóteses etiológicas biológicas e hipóteses etiológicas psicossociais. Os termos "falta de consciência dos déficits", "consciência do déficit", "insight" e "negação do déficit de memória" são utilizados nos estudos como sinônimos do termo "anosognosia", mesmo sendo, conceitualmente, diferentes. O método de avaliação mais utilizado foi o uso de questionários de discrepância entre os relatos dos pacientes e cuidadores. CONCLUSÕES: Os estudos longitudinais apresentam hipóteses etiológicas heterogêneas, além da inexistência de um padrão conceitual e metodológico de avaliação. Essas dificuldades impossibilitam a obtenção de resultados homogêneos, o que gera a necessidade de aprofundamento dos estudos na área.