The Association Between Impaired Awareness and Depression, Anxiety, and Apathy in Mild to Moderate Alzheimer's Disease: A Systematic Review

Drivers of Memory Loss Underreport in Mild Cognitive Impairment Due to Alzheimer Versus Vascular Disease

BACKGROUND

We examined drivers of self and study partner reports of memory loss in mild cognitive impairment (MCI) from Alzheimer (AD-MCI) and vascular disease (Va-MCI).

METHODS

We performed retrospective cross-sectional analyses of participants with AD-MCI (n=2874) and Va-MCI (n=376) from the National Alzheimer Coordinating Center data set. Statistical analysis utilized 2-sided t test or the Fisher exact test.

RESULTS

Compared with AD-MCI, Va-MCI subjects (24.5% vs. 19.7%, P =0.031) and study partners (31.4% vs. 21.6%, P <0.0001) were more likely to deny memory loss. Black/African Americans were disproportionately represented in the group denying memory loss in AD-MCI (20.0% vs. 13.2%, P <0.0001) and Va-MCI (33.7% vs. 18.0%, P =0.0022). Study partners of participants with these features also disproportionately denied memory loss: female (AD-MCI: 60.1% vs. 51.7%, P =0.0002; Va-MCI: 70.3% vs. 52.3%, P =0.0011), Black/African American (AD-MCI: 23.5% vs. 11.98%, P <0.0001; Va-MCI: 48.8% vs. 26.5%, P =0.0002), and <16 years of education (AD-MCI only: 33.9% vs. 16.3%, P =0.0262). In AD-MCI and Va-MCI, participants with anxiety were disproportionately represented in the group endorsing memory loss (AD: 28.2% vs. 17.4%, P <0.0001; Va: 31.5% vs. 16.1%, P =0.0071), with analogous results with depression.

CONCLUSION

The findings would suggest extra vigilance in interview-based MCI detection of persons at-risk for self-based or informant-based misreport.

Anosognosia is associated with increased prevalence and faster development of neuropsychiatric symptoms in mild cognitive impairment

Introduction

Both the loss of awareness for cognitive decline (a. k.a anosognosia) and neuropsychiatric symptoms (NPS) are common in patients with Alzheimer's disease (AD) dementia, even in prodromal stages, and may exacerbate functional impairment and negatively impact caregiver burden. Despite the high impact of these symptoms on patients and their caregivers, our knowledge of how they develop across the AD spectrum is limited. Here, we explored the cross-sectional and longitudinal associations between anosognosia and NPS in individuals with mild cognitive impairment (MCI).

Methods

We included 237 participants from the Alzheimer's Disease Neuroimaging Initiative (ADNI) with a baseline clinical diagnosis of MCI. Everyday Cognition (ECog) questionnaire scores were used to measure complaints from participants and study-partners at baseline and annually over a mean of 4.29 years [standard deviation (SD) = 2.72]. Anosognosia was defined as the study-partner having an ECog score ≥2.5/4 and the participant having an ECog score < 2.5/4 on their baseline measure and their last observation without more than two consecutive deviating observations during the follow-up period. The 12-item study-partner-rated Neuropsychiatric Inventory determined the presence or absence of specific NPS. Survival analyses were performed to analyze the frequency and temporal onset of NPS over time in individuals with and without anosognosia.

Results

Thirty-eight out of 237 participants displayed anosognosia. Groups had similar lengths of follow-up at baseline (p > 0.9), though participants with anosognosia had lower MMSE scores (p = 0.049) and a higher proportion of amyloid-positivity using PET (p < 0.001. At baseline, the frequencies of agitation (p = 0.029) and disinhibition (p < 0.001) were higher in the anosognosia group compared to the non-anosognosia group. Survival analyses showed earlier onset of seven of the 12 NPS in the anosognosia group (p's < 0.001).

Discussion

Loss of awareness for cognitive decline is associated with greater frequency and earlier onset of NPS over time in participants with MCI. These results support the hypothesis of a potential common underlying neurophysiological process for anosognosia and NPS, a finding that needs to be addressed in future studies.

Awareness of Social Functioning in People with Dementia and Its Association with Dementia Severity: Multi-Center Cross-Sectional Study

Background

People with dementia commonly have impaired social functioning and may not recognize this. This lack of awareness may result in worse outcomes for the person and their family carers.

Objective

We aimed to characterize awareness of social functioning in dementia and describe its association with dementia severity.

Methods

Multi-center cross-sectional study of people aged >65 years with dementia and family informants recruited from Germany, Japan and the United Kingdom. We used the Social Functioning in Dementia (SF-DEM) scale, assessing "spending time with other people" (domain 1), "communicating with other people" (domain 2), and "sensitivity to other people" (domain 3), and calculated lack of awareness into social functioning as the discrepancy between patient and informant ratings.

Results

108 participants with dementia (50.9% women), mean age = 78.9 years, and mean MMSE score = 22.7. Patient and informant domain 1 ratings did not differ, but patient-rating was higher than carers for domain 2 (11.2 versus 10.1; p = 0.003) and domain 3 (9.7 versus 8.1; p < 0.001). Sixty people with dementia overestimated their overall social functioning, 30 underestimated, and 18 gave ratings congruent with their informant. Performance on the MMSE and its sub-domains was not associated with SF-DEM discrepancy score.

Conclusions

We found that awareness of social functioning in dementia was a multidimensional concept, which varies according to subdomains of social functioning. Clinicians should help family members understand and adapt by explaining their relative with dementia's lack of awareness about aspects of their social functioning.

Dyadic influences on awareness of condition in people with dementia: findings from the IDEAL cohort

Introduction

The discrepancy between caregiver-ratings and self-ratings of abilities is commonly used to assess awareness in people with dementia. We investigated the contribution of caregiver and dyadic characteristics to the difference in perspective between caregiver-informants and people with dementia about difficulties experienced, when considering awareness of condition.

Methods

We conducted exploratory cross-sectional analyses using data from the IDEAL cohort. Participants were 1,038 community-dwelling people with mild-to-moderate dementia, and coresident spouse/partner caregivers. The Representations and Adjustment to Dementia Index (RADIX) checklist reporting difficulties commonly experienced in dementia was completed by 960 caregiver-informants and 989 people with dementia. Difference in scores was calculated for 916 dyads. Demographic information, cognition, informant-rated functional ability and neuropsychiatric symptoms were recorded for the person with dementia. Self-reported data were collected on mood, comorbidity, religion, importance of religion, relationship quality, and caregiver stress.

Results

For most dyads, caregivers reported more RADIX difficulties than people with dementia. Caregiver RADIX ratings were more closely associated with informant-rated functional ability and neuropsychiatric symptoms than with cognition. More RADIX difficulties and higher stress were reported by female caregivers. Greater RADIX difference was associated with more caregiver stress, and older age but less depression in people with dementia.

Conclusion

Few dyadic characteristics were important, but caregiver stress was higher where caregivers reported more RADIX difficulties and/or the difference in perspective was greater, whereas partners with dementia reported better mood. In addition to offering information about awareness of condition, the caregiver rating and difference in perspectives could indicate where more support is needed.

The dual-path hypothesis for the emergence of anosognosia in Alzheimer's disease

Although neurocognitive models have been proposed to explain anosognosia in Alzheimer's disease (AD), the neural cascade responsible for its origin in the human brain remains unknown. Here, we build on a mechanistic dual-path hypothesis that brings error-monitoring and emotional processing systems as key elements for self-awareness, with distinct impacts on the emergence of anosognosia in AD. Proceeding from the notion of anosognosia as a dimensional syndrome, varying between a lack of concern about one's own deficits (i.e., anosodiaphoria) and a complete lack of awareness of deficits, our hypothesis states that (i) unawareness of deficits would result from primary damage to the error-monitoring system, whereas (ii) anosodiaphoria would more likely result from an imbalance between emotional processing and error-monitoring. In the first case, a synaptic failure in the error-monitoring system, in which the anterior and posterior cingulate cortices play a major role, would have a negative impact on error (or deficits) awareness, preventing patients from becoming aware of their condition. In the second case, an impairment in the emotional processing system, in which the amygdala and the orbitofrontal cortex play a major role, would prevent patients from monitoring the internal milieu for relevant errors (or deficits) and assigning appropriate value to them, thus biasing their impact on the error-monitoring system. Our hypothesis stems on two scientific premises. One comes from preliminary results in AD patients showing a synaptic failure in the error-monitoring system along with a decline of awareness for cognitive difficulties at the time of diagnosis. Another comes from the somatic marker hypothesis, which proposes that emotional signals are critical to adaptive behavior. Further exploration of these premises will be of great interest to illuminate the foundations of self-awareness and improve our knowledge of the underlying paths of anosognosia in AD and other brain disorders.

Semiology and determinants of apathy across neurodegenerative motor disorders: A comparison between amyotrophic lateral sclerosis, Parkinson’s and Huntington’s disease

Background

The semiology and determinants of apathy are largely unknown across amyotrophic lateral sclerosis (ALS), Parkinson’s disease (PD), and Huntington’s disease (HD), due to both motor and non-motor confounders. This study thus aimed at (1) profiling apathy in ALS, PD, and HD and (2) exploring its clinical determinants.

Materials

Consecutive ALS (N = 99), PD (N = 73), and HD (N = 25) patients underwent a motor-free assessment of apathy (Dimensional Apathy Scale, DAS), global cognition, anxiety and depression. Function was assessed through disease-specific scales. The DAS was also completed by N = 101 healthy controls (HCs). Between-group comparisons on DAS scores were implemented by covarying for all applicable confounders. Predictive models on DAS scores were built through multiple, stepwise regressions.

Results

Parkinson’s disease and HD, but not ALS, patients were more apathetic than HCs—with HD patients also selectively showing lower initiation and poorer goal-directed planning than HCs. Higher apathetic features were detected in PD and HD as compared to ALS. Education was a protective factor against apathy in ALS. Anxiety was a risk factor for global apathy in ALS, HD, and to a lesser extent, in PD, whereas, protective only toward affective disintegration in PD and ALS. Cognitive inefficiency was a risk factor toward apathy in both PD and ALS. Depression was a risk factor for executive-related apathy in PD.

Discussion

This study provides unprecedented insights into the heterogeneous semiology and determinants of apathy across ALS, PD, and HD via the DAS, in turn informing clinical practice and research.

Pinus halepensis Essential Oil Ameliorates Aβ1-42-Induced Brain Injury by Diminishing Anxiety, Oxidative Stress, and Neuroinflammation in Rats

The Pinus L. genus comprises around 250 species, being popular worldwide for their medicinal and aromatic properties. The present study aimed to evaluate the P. halepensis Mill. essential oil (PNO) in an Alzheimer’s disease (AD) environment as an anxiolytic and antidepressant agent. The AD-like symptoms were induced in Wistar male rats by intracerebroventricular administration of amyloid beta1-42 (Aβ1-42), and PNO (1% and 3%) was delivered to Aβ1-42 pre-treated rats via inhalation route for 21 consecutive days, 30 min before behavioral assessments. The obtained results indicate PNO’s potential to relieve anxious–depressive features and to restore redox imbalance in the rats exhibiting AD-like neuropsychiatric impairments. Moreover, PNO presented beneficial effects against neuroinflammation and neuroapoptosis in the Aβ1-42 rat AD model.

Relationship between psychiatric symptoms and activities of daily living in patients undergoing hemodialysis

Background

Accurately identifying the factors contributing to decline in activities of daily living (ADL) is important for preventing such decline in patients undergoing hemodialysis (HD). We studied the prevalence and number of overlapping psychiatric symptoms (depressive symptoms, apathy, and sleep disturbance) in patients undergoing HD and examined the relationship between psychiatric symptoms and ADL.

Methods

The study utilized a cross-sectional research design. The sample included 203 outpatients (median age: 69 years) undergoing stable HD treatment three times a week. Patient characteristics, including age, sex, body composition, dialysis vintage, primary kidney disease, comorbidity, and nutritional status, were collected from patients’ medical records. Functional status was assessed based on the self-reported questionnaire that combined five basic and eight instrumental ADL items. Usual walking speed was used as an index of physical function. Additionally, the short version of the Center for Epidemiologic Studies Depression Scale was used to assess depressive symptoms. Further, apathy and sleep disturbance were assessed using the Motivation Score and the Athens Insomnia Scale, respectively.

Results

Overall, 59 (29.1%) patients demonstrated depressive symptoms, 100 (49.3%) reported apathy, 83 (40.9%) had sleep disturbance, 31 (15.3%) had three overlapping psychiatric symptoms, 43 (21.2%) had two overlapping psychiatric symptoms, 63 (31.0%) had only one symptom, and 66 (32.5%) had no psychiatric symptoms. Multiple logistic regression analysis showed that having two or three overlapping psychiatric symptoms was independently and significantly associated with ADL (functional status of 13 points for the ADL maintenance group, and of < 13 points for the ADL decline group, respectively), even after adjusting for patient characteristics and walking speed (odds ratio: 2.74, 95% confidence interval: 1.12–6.69, reference; no psychiatric symptoms).

Conclusion

The present study clarified that the overlapping symptoms, including depressive symptoms, apathy, and sleep disturbance, were independently associated with ADL decline in patients undergoing HD. It is useful to examine not only depressive symptoms but also other symptoms such as apathy and sleep disturbance to elucidate factors associated with deteriorated ADL in chronic patients. Our findings provide a strong basis for targeted interventions to prevent functional dependence in the HD population.

Risk factors for apathy in Alzheimer's disease: A systematic review of longitudinal evidence

BACKGROUND

Apathy is frequent and persistent in Alzheimer's disease (AD), associated with poor prognosis and carer distress; yet our knowledge of risk factors remains limited.

AIMS

To identify risk factors associated with apathy incidence and progression in AD over time.

METHODS

We systematically reviewed evidence based on longitudinal studies assessing risk factors for apathy in AD up to June 2021. Two authors independently assessed article eligibility and rated quality.

RESULTS

13,280 articles were screened, of which 13 met inclusion criteria. Studies had a mean follow-up of 2.7 years reporting on a total of 2012 participants. Most findings were based on single studies of moderate quality evidence. Risk factors increasing apathy onset were: being a carrier of the T allele of the PRND gene polymorphism, and having high levels of the IL-6 and TNFα cytokines at baseline. Risk factors for apathy worsening were: reduced inferior-temporal cortical thickness, taking antidepressants, being an ApoE ε4 carrier, living longer with AD, lower cognitive test scores, higher baseline apathy, premorbid personality traits (lower agreeableness, higher neuroticism), and higher midlife motivational abilities.

CONCLUSIONS

Although results are limited by the small number of studies, this review identified specific genetic, neurobiological, AD specific, and dispositional factors that may increase risk of apathy onset and worsening in AD.

Awareness of Diagnosis in Persons with Early-Stage Alzheimer's Disease: An Observational Study in Spain

Introduction

Limited information is available on people’s experiences of living with Alzheimer’s disease (AD) at earlier stages. This study assessed awareness of diagnosis among people with early-stage AD and its impact on different person-centered outcome measures.

Methods

We conducted an observational, cross-sectional study in 21 memory clinics in Spain. Persons aged 50–90 years, diagnosed with prodromal or mild AD (NIA/AA criteria), a Mini Mental State Examination (MMSE) score ≥ 22, and a Clinical Dementia Rating-Global score (CDR-GS) of 0.5 or 1.0 were recruited. The Representations and Adjustment to Dementia Index (RADIX) was used to assess participants’ beliefs about their condition and its consequences.

Results

A total of 149 persons with early-stage AD were studied. Mean (SD) age was 72.3 (7.0) years and 50.3% were female. Mean duration of AD was 1.4 (1.8) years. Mean MMSE score was 24.6 (2.1) and 87.2% had a CDR-GS score of 0.5. Most participants (n = 84, 57.5%) used a descriptive term related to specific AD symptoms (e.g., memory difficulties) when asked what they called their condition. Participants aware of their diagnosis using the term AD (n = 66, 45.2%) were younger, had more depressive symptoms, and poorer life satisfaction and quality of life compared to those without awareness of their specific diagnosis. Practical and emotional consequences RADIX scores showed a significant negative correlation with Quality of Life in Alzheimer’s Disease score (rho = − 0.389 and − 0.413, respectively; p < 0.0001). Years of education was the only predictor of awareness of AD diagnosis [OR = 1.04 (95% CI 1.00–1.08); p = 0.029].

Conclusions

Awareness of diagnosis was a common phenomenon in persons with early-stage AD negatively impacting their quality of life. Understanding illness representations in earlier stages may facilitate implementing optimized care that supports improved quality of life and well-being.

Apathy Is the Best Dimension to Consider for Awareness Assessment in Alzheimer’s Disease

Previous studies have reported the major role of apathy in awareness assessment among Alzheimer’s patients using the patient-caregiver discrepancy method, whatever the awareness dimension assessed. Using the Apathy Evaluation Scales among other awareness scales, we report that apathy is the sole awareness dimension distinguishing healthy controls (25), mild (57) and moderate-to-moderately-severe (11) Alzheimer’s patients. A linear regression showed that the Mini-Mental State Examination score used as a risk factor for non-awareness was the only factor associated with awareness of apathy and was the best predictor. This suggests that apathy is the most discriminant dimension for awareness assessment in Alzheimer’s disease.

Long-term neuropsychiatric symptoms in spontaneous intracerebral haemorrhage survivors

OBJECTIVE

Neuropsychiatric (NP) symptoms are prominent features of cognitive decline, but they have been understudied in patients with spontaneous intracerebral haemorrhage (ICH). In ICH survivors, we aimed at assessing NP symptoms prevalence and profiles, and their influence on long-term outcomes.

METHODS

We analysed data from consecutive 6-month ICH survivors enrolled in the Prognosis of Intracerebral Haemorrhage study. We performed NP evaluation using the Neuropsychiatric Inventory Questionnaire. Patients underwent long-term clinical follow-up after ICH (median follow-up time 7.2 years, IQR 4.8-8.2).

RESULTS

Out of 560 patients with ICH, 265 survived at 6 months. NP evaluation 6 months after ICH was feasible in 202 patients. NP symptoms were present in 112 patients (55%), and in 36 out of 48 patients (75%) with post-ICH dementia. Affective symptoms were present in 77 patients (38%), followed by vegetative symptoms (52 patients, 26%) and hyperactivity (47 patients, 23%). Apathy and hyperactivity were associated with post-ICH dementia and cerebral amyloid angiopathy MRI profile (all p<0.05). Apathy and hyperactivity prevailing over affective symptoms at 6-month follow-up were associated with higher risks of developing new-onset dementia (HR 5.40; 95% CI 2.27 to 12.84), while presence or severity of NP symptoms were not.

CONCLUSION

NP symptoms were present in more than half of 6-month ICH survivors, with higher prevalence and severity in patients with post-ICH dementia. Distinctive NP profile might be associated to cognitive status and inform on long-term dementia risk.

The Role of Individual Characteristics in Predicting Short- and Long-Term Cognitive and Psychological Benefits of Cognitive Stimulation Therapy for Mild-to-Moderate Dementia

Introduction: This study examined the role of individual characteristics in predicting short- and long-term benefits of the Italian version of Cognitive Stimulation Therapy (CST-IT), an evidence-based intervention for people with mild-to-moderate dementia.

Materials and Methods: Data were drawn from a sample (N = 123) of people with dementia (PwD) who took part in a multicenter controlled clinical trial of CST-IT. Assessments at pre-test, immediately after completing the treatment, and 3 months later investigated the following outcomes: general cognitive functioning and language, mood and behavior, everyday functioning, and quality of life. Age, education and baseline (pre-test) cognitive functioning, mood (depression) and behavioral and neuropsychiatric symptoms were considered as predictors of any short- and long-term benefits.

Results: Linear mixed-effects models showed that different individual characteristics -particularly education and age- influenced the benefits of CST-IT, depending on the outcome measures considered. Higher education predicted larger gains in general cognitive functioning and, along with less severe depressive symptoms, in language (magnification effects). Older age was associated with positive changes in mood (compensation effects). Albeit very modestly, older age was also associated with larger gains in everyday functioning (compensation effects). Gains in quality of life were predicted by older age and lower education (compensation effects). Baseline cognitive functioning, mood and/or behavioral symptoms broadly influenced performance too, but their role again depended on the outcomes considered.

Discussion: These findings underscore the importance of considering and further exploring how psychosocial interventions like CST are affected by individual characteristics in order to maximize their efficacy for PwD.

Does awareness of condition help people with mild-to-moderate dementia to live well? Findings from the IDEAL programme

Background

People living with dementia vary in awareness of their abilities. We explored awareness of the condition and diagnosis in people with mild-to-moderate dementia, and how this relates to quality of life, well-being, life satisfaction, and caregiver stress.

Methods

This study was a cross-sectional exploratory analysis of data from the IDEAL cohort, which recruited people with dementia living at home and available caregivers from 29 research sites in Great Britain. Our study included 917 people with mild-to-moderate dementia and 755 carers. Low and high awareness groups were derived from self-reported responses to a dementia representation measure. Logistic regression was used to explore predictors of awareness of condition and diagnosis using demographic, cognitive, functional and psychological measures, and the relationship with quality of life, well-being and life satisfaction (‘living well’), and caregiver stress.

Results

There were 83 people with low awareness of their condition. The remaining 834 people showed some awareness and 103 of these had high awareness of their condition and diagnosis. Psychosocial factors were stronger predictors of awareness than cognitive and functional ability. Those with higher awareness reported lower mood, and lower scores on indices of living well as well as lower optimism, self-efficacy and self-esteem. Low awareness was more likely in those aged 80y and above, and living in more socially deprived areas. No relationship was seen between caregiver stress and awareness.

Conclusions

Awareness of the condition and diagnosis varies in people with mild-to-moderate dementia and is relevant to the capability to live well. Awareness should be considered in person-centered clinical care.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-021-02468-4.

Awareness dimensions and associated factors in Alzheimer's disease

OBJECTIVES

We recently reported the major role depression and apathy in awareness among Alzheimer patients, using the stage of the disease as an exposure factor and exploring different assessment methods. Using the same patient data, we aimed here to explore the different dimensions of awareness assessed by different sub-scales in awareness scales.

METHOD

Sixty-one Alzheimer patients were examined using four awareness scales relating to three assessment methods: (a) patient-caregiver discrepancy; (b) clinical rating; and (c) prediction of performance discrepancy. Global cognition, executive functioning, autonomy, depression and apathy were also assessed. Multivariate logistic models were performed using disease stage as an exposure factor for awareness scales and sub-scales. Correlations across the different factors and patient and caregiver awareness ratings were computed.

RESULTS

The patient-caregiver discrepancy and clinical rating methods (a, b) both identified the factors associated with awareness in the overall scales and the sub-scales as being depression and/or apathy. Depression correlated with patient self-ratings while apathy correlated with caregiver ratings. The prediction of performance discrepancy method (c) identified different factors in the overall scale, executive factors in three sub-scales involving executive domains and the memory factor in a sub-scale involving the mnesic domain.

DISCUSSION

The awareness scales using a referential based on a human rating (a, b) suggest that awareness is unidimensional, with depression impacting self-reports and apathy influencing caregiver/clinical reports. Scales based on a test rating (c) appear to be more closely associated with the dimensions assessed. This highlights the role of the reference system for awareness assessment in Alzheimer's disease.

Revisiting Apathy in Alzheimer's Disease: From Conceptualization to Therapeutic Approaches

Apathy is a neurobehavioral syndrome characterized by impaired motivation for goal-directed behaviors and cognitive activity, alongside blunted affect. Apathy is a common neuropsychiatric syndrome in Alzheimer's disease (AD), with a 5-year prevalence over 70%. Apathy also serves as a prognostic indicator, correlating with the progression of AD. Despite advances in its conceptualization and understanding of its neural basis, there is very limited empirical evidence to support the available strategies for the treatment of apathy in AD. Given its complex pathophysiology, including distinct substrates for different apathy dimensions (affective, cognitive, and behavioral), it is unlikely that a single pharmacological or nonpharmacological strategy will be effective for all cases of apathy in AD. High-quality evidence research is needed to better understand the role of specific strategies aiming at a personalized approach.