The Relationship Between Decision-Making Capacity and Awareness in People with Young-Onset Alzheimer’s Disease

Abstract

Background:

Young-onset AD (YOAD) typically occurs before the age of 65 and affects less than 6% of all people diagnosed with AD. There is a lack of research on differences between decision-making capacity and awareness according to age at onset of dementia.

Objective:

We investigated the relationship between decision-making capacity and awareness domains in people with young- (YOAD) and late-onset Alzheimer’s disease (LOAD).

Methods:

A cross-sectional study included 169 consecutively selected people with AD and their caregivers (124 people with LOAD and 45 people with YOAD).

Results:

People with YOAD were more cognitively impaired, but more aware of their cognitive deficits and health condition, with moderate effect sizes. All people with AD presented deficits in the domains of decision-making capacity, with more impairment in understanding. There was a relationship between understanding and awareness domains, such that awareness was particularly important for decision-making capacity in the YOAD group.

Conclusions:

Better awareness involved better understanding in the YOAD group. Clinically, our findings shed light on the need to consider the differences in the domains of awareness and their relationship with other clinical aspects such as decision-making capacity according to age at onset of AD. Furthermore, our data can suggest hypotheses for larger and more robust prospective studies.

Keywords

Alzheimer’s disease awareness decision-making capacity domains of decision-making capacity late onset young onset

INTRODUCTION

Alzheimer’s disease (AD) is the most common form of dementia, accounting for 50 to 75% of dementia cases. AD is characterized by gradually progressive cognitive and functional deficits and behavioral changes. 1 Age is considered the principal risk factor for AD and is used as a categorical marker. 2

Young-onset AD (YOAD) typically occurs before the age of 65 and affects less than 6% of all people diagnosed with AD. Although the impact of AD is significant at any age, people with YOAD may face unique challenges such as psychological damage involving anxiety and depression, risk of stigmatization, decreased and/or poor judgment, withdrawal from work or social activities, and even withdrawal from family and friends. 3 In addition, people with YOAD may face stigma related to the disease, like feeling denied and ignored and experiencing discrimination in healthcare. 4

People with YOAD differ from the late-onset group in several clinical, neuropsychological, neuroimaging, and neuropathological variables. Various studies have indicated that people with YOAD experience a more aggressive clinical course of the illness. In 25% of YOAD cases, there is a distinct phenotype of non-memory symptoms, particularly apraxia, visual dysfunction, fluent or non-fluent aphasia, executive dysfunction, and/or dyscalculia. 5 Given the specific clinical profile of people with YOAD is important to evaluate their pattern of functioning in other aspects such as decision-making capacity and awareness.

Decision-making capacity is the process of making choices by identifying a decision, gathering information, assessing alternative solutions, and selecting an appropriate action from several possible alternatives. 6 It involves many cognitive processes to determine the proper course of action, including the choice of a motivation to achieve the goal, weighing the likely consequences of different options, and deciding which expected consequences would best fit the objectives. 6

The decision-making process encompasses four major abilities: 6 1) Understanding the relevant information is the gathering, storage, and recall of the meaning of sequences of information. The person must show the capacity to explain such information in his/her own words. 2) Appreciate the implications of contextualized information is the capacity related to personal values about the benefits and risks of a choice. 3) Reasoning about the information is the logical process of comparing the alternative answers, indicating the reason for the choice. It requires rational agreement with the conclusion. 4) Expression of choice is the ability to change a choice and maintain its consistency until the moment of its implementation. 7 Any interference in one of these abilities impairs decision-making capacity.

Decision-making capacity can change with aging. 8 Therefore, the capacity to make decisions is assumed to be vulnerable to the interaction between age and low cognitive ability. 9 If the decision-making process is vulnerable to normal aging, it can be impacted even more seriously in pathological aging, since the cognitive, emotional, and motivational capacities are considerably affected by age-related neurodegenerative disorders such as AD.10 –12 Recent studies have shown that people with AD (PwAD) present deficits in the domains of the decision-making capacity, with more serious impairment of understanding and reasoning.13,14, 13,14 However, no previous study has investigated decision-making capacity in people with YOAD. Thus, it is necessary to better understand the impact of age at onset of AD on decision-making capacity.

Awareness is described as the capacity to recognize changes caused by one’s illness.15,16, 15,16 Awareness is a multidimensional construct with different domains, such as awareness of cognitive deficit, functional impairment, emotional and social difficulties, and behavioral disturbances.15 –17 The construct integrates biological, social, and psychological levels and should not be considered as a symptom of the disease. 16

Recent studies on dementia have emphasized the need to relate awareness to specific domains of functioning. 18 Most people with AD present deficits in awareness, with greater impairment in the domains of awareness of cognitive functioning and health conditions and functional activity.13,19,20 , 13,19,20

In a recent study, 13 we investigated the relationship between decision-making capacity and awareness. People with AD who were aware of their cognitive functioning and health condition were more likely to be judged competent in their decision-making capacity. Other studies have shown that deficits in awareness in people with dementia have been related to significant impairment in the understanding, appreciating, and reasoning domains of decision-making capacity.21,22, 21,22

Interestingly, people with YOAD have been considered to have better awareness, although they experience greater cognitive impairment.3,4,23 , 3,4,23 Their atypical cognitive profile may partially explain the report of preserved awareness in people with YOAD, since they often present more preserved memory at the time of diagnosis, as opposed to people with LOAD. For example, Baptista et al. 4 found that people with YOAD were more aware of the disease and in the domain of cognitive functioning and health condition than people with LOAD, even in the moderate disease stage.

Recent studies have suggested that people with AD who are aware of their overall cognitive function and diagnosis are more likely to be judged competent in decision-making capacity. 13 Therefore, the novelty of our study is that it fills a relative gap in research on the relationship between decision-making capacity and awareness in people with YOAD. In this context, we aim to analyze the relationship between decision-making capacity and awareness in people with YOAD and LOAD. We hypothesize that people with YOAD have significantly higher awareness and more decision-making capacity than people with LOAD.

METHODS

Participants

In this cross-sectional study, we included 169 consecutively selected PwAD and their caregivers (124 people with LOAD and 45 people with YOAD), according to the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), enrolled at the Center for Alzheimer's Disease and Related Disorders of the Institute of Psychiatry (IPUB), Universidade Federal do Rio de Janeiro (UFRJ), Brazil. A psychiatrist performed the diagnosis using clinical interviews with the PwAD and their caregivers as well as cognitive screening tests, laboratory tests, and imaging.

Only patients with mild to moderate AD according to the Clinical Dementia Rating scale (CDR), 24 with scores between 11 to 26 on the MMSE, 25 were included in the study. We excluded people with history of neurological or psychiatric disorders, aphasia, head trauma, epilepsy, and alcohol or drug abuse.

The primary family caregiver was defined as the person who was most responsible for the care of the PwAD. Caregivers with reported history of psychiatric or cognitive disorders were excluded from the study. All caregivers had been previously informed of the diagnosis by the psychiatrist.

Ethics

The study complied with the ethical guidelines of the revised Declaration of Helsinki. The Institutional Review Board of the Institute of Psychiatry (IPUB), Universidade Federal do Rio de Janeiro (UFRJ), approved the study. All PwAD and their caregivers signed the informed consent term, after a detailed explanation of the study.

Procedures

The assessments were performed by trained psychologists from the research team. The PwAD and their caregivers were interviewed separately. The PwAD had their decision-making capacity, awareness of the disease, and cognitive functioning assessed. Caregivers provided information about the PwAD (demographics, disease severity, functional capacity, mood, neuropsychiatric symptoms). We presented the instruments in the same order for all the participants. We provided the participants with some help to allow their better performance in the interview. For the PWAD interview, the research assistant read the questions with accompanying large-type visual displays of the answer choices. If a PWAD expressed confusion over the question or its answer choices, the research assistant attempted to clarify the source of confusion.

Instruments

Awareness of disease: Assessment Scale of Psychosocial Impact of the Diagnosis of Dementia (ASPIDD), a 30-question scale based on PwAD and caregiver reports. The scale assesses awareness of the disease across the following domains: awareness of cognitive functioning and health condition, functional activity impairments, emotional state, social functioning, and relationships. The awareness score is the degree of discrepancy between the patient’s and the caregiver's responses, with one point being scored for each discrepant response. Total scores of awareness range from preserved (0–4), mildly impaired (5–11), and moderately impaired (12–17) to absent (over 18). The scores for domains are given as: awareness of cognitive functioning and health condition (0–7), emotional state (0–5), social functioning and relationships (0–7), and functional activity impairments (0–11). 17

Decision-making capacity: MacArthur Competence Assessment Tool for Treatment (MacCAT-T) is a semi-structured interview about competence to consent to treatment, focused on the four decision-making abilities. The interview covers information about the individual's symptoms, diagnosis, treatment options, risks and benefits of treatment, and alternative treatments. The section Understanding is subdivided into Understanding of Disease, Treatment, and Risks and Benefits of Treatment. In this section, the participant should be capable of paraphrasing what has just been spoken to them. The Appreciation section assesses whether the individual can apply the information to his or her own context (Appreciation of the Disease) and whether they recognize the possible benefits of the treatment (Appreciation of the Treatment). In the Reasoning section, the person is asked to mention any consequences of the treatment alternatives (Consequential Reasoning), compare the alternatives (Comparative Reasoning) and offer different consequences not previously mentioned by the interviewer (Generating Consequences). This section also assesses the logical consistency of the person’s choice. In the Expression of Choice, the individual is asked to state a preference for one treatment option. The scores for each item are 2 (adequate), 1 (partially adequate), or 0 (inadequate). There is one quantitative score for each ability: 0–6 for understanding, 0–4 for appreciation, 0–8 for reasoning, and 0–2 for expression of a choice. There is no total score for the MacCAT-T or a cutoff score to determine whether the individual is competent to make decisions about their treatment process, because the interviewer’s judgment must consider clinically relevant overall information.14,26, 14,26

Dementia severity: The CDR measures the severity of dementia. The stages range from 0 (no dementia) to 3 (severe dementia) according to the degree of cognitive, behavioral, and activities of daily living impairment. A higher score denotes more severe dementia. 24

Cognition: The MMSE includes tasks involving orientation, registration, short-term memory, language use, comprehension, and basic motor skills. The total score ranges from 0 to 30. Lower scores indicate more impaired cognition. 25

Functionality: Pfeffer Functional Activities Questionnaire (PFEFFER) is a caregiver/reporter inventory that evaluates activities of daily living. The ratings for each item range from normal (0) to dependent (3), with a total of 30 points. Higher scores indicate worse functional status. 28

Depressive symptoms: Cornell Scale for Depression in Dementia (CSDD) assesses mood symptoms, physical symptoms, circadian functions, and behavioral symptoms related to depression. Scores above 13 indicate the presence of depression.29,30, 29,30

Neuropsychiatric symptoms: Neuropsychiatric Inventory (NPI) is a questionnaire that evaluates the presence of delusions, hallucinations, dysphoria, anxiety, agitation/aggression, euphoria, disinhibition, irritability/lability, apathy, aberrant motor activity, night-time behavior disturbances, and appetite and eating abnormalities. Each item is rated for frequency and intensity. The total scores range from 0 to 144 points. Higher scores indicate higher presence of neuropsychiatric symptoms. 31

Quality of life: The questionnaire Quality of Life in Alzheimer's Disease Scale (QoL-AD) was developed specifically to assess QoL in dementia. The QoL-AD includes 13 domains: physical health, energy, mood, living situation, memory, family, marriage, friends, chores, fun, money, self, and life as a whole. The 13 domains are rated as poor (1), fair (2), or good (3), and the total scores range from 13 to 52. Higher scores indicate better self-reported QoL.32,33, 32,33

Social and emotional functioning: The Social and Emotional Questionnaire (SEQ) consists of 30 items distributed across 5 aspects: recognition of emotion, empathy, social conformity, antisocial behavior, and sociability. The ratings are scored on a 5-point Likert scale, from strongly disagree (1) to strongly agree (5). The patient’s and caregiver’s versions are essentially identical. Both patients and informants were asked to answer the questionnaire individually. This ensured anonymity of answers as well as prevention of cross-checking answers between PwAD and informants. People with dementia rated their socioemotional functioning as regards the ability to recognize emotions, their behavior in social situations, and the extent of their empathetic reactions. Caregivers also answered questions about the current emotional and social functioning of the person with dementia. The score is based on the degree of discrepancy between PwAD and their caregivers’ ratings. Discrepancy scores close to 0 indicate good mutual agreement. Positive and negative discrepancy scores are interpreted as indicating lower awareness.34,35, 34,35

Statistical analysis

All the statistical analyses were performed with SPSS for Windows version 22.0. The Kolmogorov-Smirnov and Levene tests were used to verify the data’s normal distribution and homoscedasticity, respectively.

We used the independent t-test, chi-square test, and analysis of variance (ANOVA) to assess the relationship between sociodemographic and clinical variables in both groups. We used Cohen’s d (small (<0.5), moderate (0.5–0.8), or high (>0.8) effects) and Phi (range is from –1 to 1, higher values indicate a stronger correlation between the two variables) or Cramer’s V (0 (reflecting complete independence) and 1.0 (indicating complete dependence or association) for chi-square test to measure effect size in relation to the differences in socio-demographic and clinical characteristics of the caregivers and people with AD.

Multivariate linear regression models controlling age at onset and education level were performed to determine the factors related to the domains of awareness and the decision-making capacity. The best models were selected based on trade-off between the highest variance (R²) and highest cross-validity (adjusted R²). For all the analyses, the level of significance adopted was p≤0.05.

RESULTS

Sociodemographic and clinical characteristics of people with YOAD and LOAD

People with YOAD (N = 45) had a mean age at onset of 57.98 years (4.34), mean age of 63.22 years (5.43), and 5 years mean duration of the disease (3.26). The majority of the YOAD group (N = 25; 55.6%) were in the mild stage of the disease (CDR 2). They had a mean of 9.93 (4.10) years of education, and 55.6% were females (N = 25).

People with LOAD (N = 124) had mean age at onset of 75.36 years (5.78), mean age of 79.92 years (5.60), and 4 years mean duration of the disease (3.14). Most of the LOAD group (N = 84; 67.7%) were in the mild stage of the disease (CDR 1). They had a mean of 7.35 (3.88) years of education, and 69.4% were females (N = 86).

There was a significant difference in age (p = 0.001; d = 3.02) and in age at onset with (p = 0.001; d = 3.22), with a high effects size between groups.

People with YOAD were more cognitively impaired, with moderate effect size, compared to people with LOAD (p = 0.003; d = 0.53).

Table 1 shows the comparison of demographics and clinical data between people with YOAD and LOAD.

Table 1
Sociodemographic and clinical data on a sample of people with Alzheimer's disease

Variables YOAD LOAD Significance Effect size

(N = 45) (N = 124)

Age – y (mean±SD) 63.22 (5.43) 79.92 (5.60) 0.001^* 3.02^**

Males N (%) 20 (44.4) 37 (30.6) 0.003^* 0.003^*

Females N (%) 25 (55.6) 86 (69.4) 0.003^* 0.003^*

Disease duration – y (mean±SD) 5.24 (3.26) 4.56 (3.14) 0.220 0.22^**

Age at onset – y (mean±SD) 57.98 (4.34) 75.36 (5.78) 0.001^* 3.22^**

Schooling – y (mean±SD) 9.93 (4.10) 7.35 (3.88) 0.001^* 0.66^

CDR

Questionable Dementia N (%) – 1 (0.8) 0.257 0.257^*

Mild stage N (%) 25 (55.6) 84 (67.7) 0.257

Moderate stage N (%) 20 (44.4) 39 (31.5) 0.257

MMSE – mean (±SD) 16.98 (4.47) 19.27 (4.28) 0.003^* 0.53^

PFEFFER mean (±SD) 18.73 (7.62) 16.73 (8.43) 0.163 0.1^

NPI – mean (±SD) 22.56 (18.55) 17.65 (18.17) 0.125 0.27^

SEQ – mean (±SD 0.10 (0.17) 0.07 (0.21) 0.351 0.15^

Qol-AD – mean (±SD) 33.42 (6.23) 33.65 (4.90) 0.809 0.04^**

Variables	YOAD	LOAD	Significance	Effect size
Age – y (mean±SD)	63.22 (5.43)	79.92 (5.60)	0.001^*	3.02^**
Males N (%)	20 (44.4)	37 (30.6)	0.003^*	0.003^*
Females N (%)	25 (55.6)	86 (69.4)	0.003^*	0.003^*
Disease duration – y (mean±SD)	5.24 (3.26)	4.56 (3.14)	0.220	0.22^**
Age at onset – y (mean±SD)	57.98 (4.34)	75.36 (5.78)	0.001^*	3.22^**
Schooling – y (mean±SD)	9.93 (4.10)	7.35 (3.88)	0.001^*	0.66^**
CDR
Questionable Dementia N (%)	–	1 (0.8)	0.257	0.257^***
Mild stage N (%)	25 (55.6)	84 (67.7)	0.257
Moderate stage N (%)	20 (44.4)	39 (31.5)	0.257
MMSE – mean (±SD)	16.98 (4.47)	19.27 (4.28)	0.003^*	0.53^**
PFEFFER mean (±SD)	18.73 (7.62)	16.73 (8.43)	0.163	0.1^**
NPI – mean (±SD)	22.56 (18.55)	17.65 (18.17)	0.125	0.27^**
SEQ – mean (±SD	0.10 (0.17)	0.07 (0.21)	0.351	0.15^**
Qol-AD – mean (±SD)	33.42 (6.23)	33.65 (4.90)	0.809	0.04^**

YOAD, young-onset dementia; LOAD, Late-onset dementia; SD, standard deviation; CDR, Clinical Dementia Rating; MMSE, Mini-Mental State Examination; PFEFFER, Pfeffer Functional Activities Questionnaire; NPI, Neuropsychiatric Inventory; SEQ, Social and Emotional Questionnaire; QoL-AD, Quality of life in Alzheimer's disease-patient’s self-report. ^* p≤0.005; ^*Phi; ^** Cohen d, ^***Cramer’s V.

Differences in awareness and decision-making capacity

Regarding awareness and its domains, people with YOAD were more aware of their cognitive deficits and health condition (p = 0.006; d = 0.49), with a moderate effect size between groups. We did not find any other significant differences between the groups in the other domains of awareness.

In addition, there were no significant differences in the domains of decision-making capacity between groups. All PwAD presented deficits in the domains of decision-making capacity with a greater impairment of understanding with a small effect size (YOAD = mean 3.67, SD 1.57; LOAD = mean 3.80, SD 1.22; d = 0.1).

Table 2 summarizes the differences between awareness and the domains of decision-making capacity.

Table 2

Awareness and Decision-Making Capacity domains

Variables	YOAD (N = 45)	LOAD (N = 124)	Significance	Effect size
	Mean (SD)	Mean (SD)		Cohen d
ASPIDD Total	8.78 (5.65)	9.73 (4.93)	0.291	0.19
ASPIDD Cognitive Deficits and Health Condition	2.02 (1.82)	2.83 (1.62)	0.006^*	0.49
ASPIDD Emotional State	1.51 (1.50)	1.45 (0.13)	0.817	0.08
ASPIDD Social Functioning and Relationships	1.13 (1.21)	1.31 (0.10)	0.384	0.29
ASPIDD Functional Activity Impairment	4.11 (3.04)	4.23 (0.23)	0.81	0.08
MacCAT-T Understanding	3.67 (1.57)	3.80 (1.22)	0.658	0.1
MacCAT-T Appreciation	2.81 (1.14)	2.66 (1.14)	0.535	0.13
MacCAT-T Reasoning	2.78 (1.98)	3.31 (1.80)	0.531	0.52
MacCAT-T Expression of a choice	1.44 (0.84)	1.68 (0.64)	0.236	0.35

ASPIDD, Assessment Scale of Psychosocial Impact of the Diagnosis of Dementia; MacCAT-T, MacArthur Competence Assessment Tool for Treatment. ^* p≤0.005.

3.3 Multivariate analysis

Multivariate linear regression models controlled by age at onset and education level were built to examine the association between awareness and the domains of MacCAT-T.

Understanding was the domain of MacCAT-T most significantly associated with awareness domains: ASPIDD Total (p < 0.001), awareness of cognitive deficits and health condition (p < 0.001), awareness of emotional state (p < 0.008), awareness of social functioning and relationships (p < 0.001), and awareness of impaired functional activity (p < 0.001). However, age at onset only impacted total ASPIDD (p < 0.013) and awareness of cognitive deficits and health condition (p < 0.001). Therefore, in these domains, people with YOAD showed better understanding when they presented better awareness. The level of education was not statically significant for awareness domains.

Table 3 shows the adjusted R² values and the regression weights.

Table 3

Regression models of awareness and decision-making capacity in YOAD and LOAD

Variables	B	t	R²	Adj R²	β	Significance
ASPIDD Total			0.320	0.285		<0.001
Understanding	–2.303	–5.327			–0.572	<0.001^*
Appreciation	–0.137	–0.295			–0.030	0.769
Reasoning	0.253	0.900			0.090	0.370
Expression of a choice	0.274	.0409			0.036	0.684
YOAD/LOAD	2.55	2.484			0.201	0.014
Education	0.019	0.185			0.015	0.854
ASPIDD Cognitive Deficits and Health Condition			0.419	0.389		<0.001
Understanding	–0.778	–6.004			–0.596	<0.001^*
Appreciation	–0.100	–0.717			–0.067	0.475
Reasoning	0.048	0.571			0.053	0.569
Expression of a choice	0.035	0.176			0.015	0.860
YOAD/LOAD	0.996	3.271			0.245	<0.001^*
Education	–0.004	–0.144			–0.011	0.885
ASPIDD Emotional State			0.074	0.026
Understanding	–0.367	–2.633			–0.330	0.010
Appreciation	0.092	0.613			0.072	0.541
Reasoning	0.074	0.811			0.094	0.419
Expression of a choice	0.082	0.379			0.039	0.706
YOAD/LOAD	0.361	1.102			0.104	0.273
Education	0.010	0.317			0.030	0.752
ASPIDD Social Functioning and Relationships			0.074	0.026
Understanding	–0.367	–2.633			–0.330	0.002
Appreciation	0.092	0.13			0.072	0.541
Reasoning	0.074	0.811			0.094	0.419
Expression of a choice	0.082	0.379			0.039	0.706
YOAD/LOAD	0.361	1.102			0.104	0.372
Education	0.010	0.317			0.030	0.752
ASPIDD functional activity impairment			0.126	0.080
Understanding	–0.352	–3.307			–0.403	0.001^*
Appreciation	–0.242	2.111			0.242	0.037
Reasoning	0.029	0.411			0.046	0.681
Expression of a choice	–0.193	–1.169			–0.118	0.245
YOAD/LOAD	0.361	1.444			0.133	0.151
Education level	0.019	0.746			0.068	0.457

B, Linear coefficient; β, Standard beta coefficient; R², Coefficient of determination; Adj. R2, adjusted R-square; ASPIDD, Assessment Scale of Psychosocial Impact of the Diagnosis of Dementia; MacCAT-T, MacArthur Competence Assessment Tool for Treatment. ^* p≤0.005.

DISCUSSION

To the best of our knowledge, this was the first study on the relationship between awareness and decision-making capacity according to age at onset of AD. The study thus aimed to investigate whether there was a relationship between decision-making capacity domains and awareness domains in people with YOAD and LOAD.

The dementia process in YOAD is characterized by a more rapid course of the disease. 36 Although most of the group participants presented mild disease, according to the CDR, people with YOAD were more cognitively impaired than those with LOAD. Moreover, the YOAD group, numerically, presented less functional ability and more neuropsychiatric symptoms. A possible explanation for the lack of clinical differences between the groups might be related to the small size of the YOAD group, a bias that might have hindered the expected variances in functionality and neuropsychiatric symptoms between the groups.

We had hypothesized that people with YOAD would have significantly higher awareness and more decision-making capacity compared to people with LOAD.

Regarding the domains of decision-making capacity, when the YOAD and LOAD groups were compared, there were no significant differences between the groups. However, the YOAD group presented a slightly worse level of understanding, reasoning, and expression of choice but a higher appreciation ability when compared to the LOAD group. The lack of significant differences between the groups was probably related to the small size of the YOAD group since there was a moderate effect size in the reasoning domain. Therefore, further studies with more robust samples might better evaluate the differences in decision-making capacity between age at onset groups.

Surprisingly, there were only significant differences between groups, with moderate effect size, in awareness of cognitive deficits and the health condition domain. This finding is consistent with previous studies that also observed that YOAD is related to greater awareness in the cognitive domain, despite the greater cognitive impairment of this group.36 –38 Possibly, people with YOAD are exposed to a more demanding environment than the older population. This may be due to them still being in the workforce, having an active social life, and possibly having dependent children. Despite their cognitive difficulties, they may be more stimulated. 38 Moreover, both the YOAD and LOAD groups presented mildly impaired awareness in the domains of social functioning and relationships and emotional state. These results are consistent and support the heterogeneity of awareness in AD found in other studies.20 –24 The existence of several types of perceptions and judgments involved in the recognition of the various awareness domains might be a reason for these disparities. 20

The YOAD group is better educated, and higher education is often associated with better cognitive reserve, which may provide some level of protection against cognitive decline seen in AD. 39 Education can have a multifaceted impact on decision-making capacity. Educated individuals may have developed more effective cognitive strategies, better problem-solving skills, or heightened awareness of their cognitive abilities. These factors can affect how they adjust to changes in decision-making capacity as AD progresses.38,39, 38,39 Therefore, we controlled the regression models to investigate the impact of education in ASPIDD domains. The findings indicated that the level of education was not statically significant for awareness domains. Thus, it might be possible that awareness can vary widely among individuals regardless of their education level. 26 Further studies with larger samples may be better suited to stratify levels of education and their possible relationship with awareness and decision-making capacity in AD.

We also analyzed the relationship between awareness domains and decision-making, controlled by age at onset. Our major finding was a relationship between the understanding and awareness domains. We found that understanding was the domain of decision-making capacity most significantly associated with awareness domains. Age at onset only impacted the total awareness score and awareness of cognitive deficits and health condition domains. In these domains, the results showed that there are two explanatory elements for awareness variation. First, awareness decreased when there were LOAD cases compared to the results of the YOAD group. This result was only obtained when we controlled for variables in the decision-making domain. Secondly, awareness improved for each increase in the individual’s understanding, when controlled by age at onset. Therefore, awareness was particularly important for decision-making capacity in the YOAD group. Understanding is the ability to comprehend information relevant to the decision. 14 Thus, better awareness implies better understanding in the YOAD group. Our findings highlight the importance of awareness for decision-making capacity. Previous studies have shown a critical role of metacognitive characteristics, such as awareness, in predicting whether an individual will be able to display decision-making competence. 38 For example, Consentino et al. 22 reported decreased decision making-capacity in unaware people with dementia. In addition, in a previous study, 13 we found that people with AD who presented either impaired awareness of the disease or cognitive and functional impairments were unable to appreciate the personal benefits of a proposed health treatment or to understand and accurately judge the personal repercussions of a decision. Therefore, this study can be considered a starting point for future studies. We should proceed to studies with a larger sample to deepen the understanding of the role of awareness in decision-making capacity in people with YOAD.

Clinical implications

Healthcare professionals need to be aware of the individual's cognitive abilities and level of awareness to make informed decisions about their medical life. 39 Understanding the specific challenges people with AD face in decision-making can help healthcare providers tailor treatment plans that align with the individual's abilities and preferences. It may involve more collaboration with family members or caregivers to ensure that people with AD needs and wishes are considered. This knowledge can influence how support systems are designed in case of care agreements. It might lead to more comprehensive and flexible care plans that adapt to the individual’s cognitive function changes. Wilkins, 38 points out that the caregivers usually underestimate the decision-making capacity of the person with AD, as they are impacted by the burden, depression, the person with AD functional ability, and the type of relationship. Currently, there are discussions about using tools, such as advanced directives, which determine the wishes and preferences of the person with dementia based on prior knowledge of values and preferences that can help in decision-making capacity. Considering that people with YOAD have better awareness when evaluating the decision-making capacity of people with YOAD, one should not only take into account cognitive impairment but rather the degree of preservation of awareness so that their decision-making capacity can be better understood and supported. Decision-making capacity is related directly to quality of life. Therefore, a person with AD who has a higher participation in their choices will tend to have a better quality of life, even if the choices are assisted and supported.39,40, 39,40

Limitations

We studied a small sample of people with YOAD cross-sectionally, which may have limited the analysis power and causal explanations. A longitudinal study would allow to observe the variations and the relationship between awareness and decision-making capacity over time. In addition, the sample was collected at an outpatient center for dementia, which hinders generalization of the results to people with dementia that are not receiving such specialized clinical support.

Conclusion

People with YOAD presented more preserved awareness of their cognitive functioning and health status than the LOAD group. In addition, awareness plays an essential role in the understanding domain of decision-making capacity. Clinically, our findings shed light on the need to consider the differences in the domains of awareness and their relationship with other clinical aspects such as decision-making capacity according to age at onset of AD. Furthermore, our data can suggest hypotheses for larger, more robust, prospective studies.

AUTHOR CONTRIBUTIONS

Natalie Souza (Investigation; Methodology; Writing – original draft; Writing – review & editing); Pedro Simões Neto, PhD (Formal analysis); Marcia Cristina Nascimento Dourado (Conceptualization; Project administration; Supervision; Writing – review & editing).

Footnotes

ACKNOWLEDGMENTS

Marcia Cristina Nascimento Dourado receives research funding from The National Council for Scientific and Technological Development (CNPq) and Carlos Chagas Filho Foundation for Research Support of the State of Rio de Janeiro (FAPERJ) grant number E-26/200.932/2021.

FUNDING

The authors have no funding to report.

CONFLICT OF INTEREST

All authors have no conflict of interest to report.

DATA AVAILABILITY

The data supporting the findings of this study are available within the article and/or its supplementary material.

References

American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 5th ed. Arlington, VA: American Psychiatric Association, 2013.

Alzheimer’s disease facts and figures. Alzheimers Dement 2021; 17: 327–406.

Werner

, Stein-Shyachman

and Lorcyn

. Early onset dementia: Clinical and social aspects. Int Psychogeriatr 2009; 21: 631–636.

Baptista

, Santos

, Kimura

, et al. Differences in awareness of disease between young-onset and late-onset dementia. Alzheimer Dis Assoc Disord 2019; 33: 129–135.

Sciancalepore

. Neuroimaging and neuropsychological differences between early-onset Alzheimer and late-onset Alzheimer. Alzheimer's Disease and Treatment. MedDocs Publishers 2021; 3: 31–36.

Appelbaum

and Grisso

. Assessing patients capacities to consent to treatment. N Engl J Med 1988; 319: 1635–1638.

Grisso

and Appelbaum

. MacArthur Competence Assessment Tool for Treatment (MacCAT-T). Sarasota, FL: Professional Resources Press, 1998.

Darby

and Dickenson

. Dementia, decision-making and capacity. Harv Rev Psychiatry 2017; 25: 270–278.

Aalten

, van Valen

, De Vugt

, et al. Awareness and behavioral problems in dementia patients: A prospective study. Int Psychogeriatr 2006; 18: 3–17.

10.

Pertl

, Benke

, Zamarian

, et al. Effects of healthy aging and mild cognitive impairment on a real-life decision-making task. J Alzheimers Dis 2017; 58: 1077–1087.

11.

Ergis

and Eusop-Roussel

. Les troubles précoces de la mémoire épisodique dans la maladie d'Alzheimer. Rev Neurol 2008; 164: 96–101.

12.

Bherer

, Belleville

and Hudon

. Le déclin des fonctions exécutives au cours du vieillissement normal, dans la maladie d'Alzheimer et dans la démence frontotemporale. Psychol NeuroPsychiatr Vieillissement 2004; 2: 181–189.

13.

de Souza

NAP

, de Oliveira

, de Carvalho

RLS

, et al. The relationship between decision-making capacity and the domains of awareness in Alzheimer disease. Alzheimer Dis Assoc Disord 2022; 36: 58–63.

14.

Santos

, Sousa

, Simões

, et al. MacArthur competence assessment tool for treatment in Alzheimer disease: Cross-cultural adaptation. Arq Neuropsiquiatr 2017; 75: 36–43.

15.

Starkstein

, Sabe

, Chemerinski

, et al. Two domains of anosognosia in Alzheimer's disease. J Neurol Neurosurg Psychiatry 1996; 61: 485–490.

16.

Clare

. The Construction of awareness in early-stage Alzheimer's disease: A review of concepts and models. Br J Clin Psychol 2004; 43: 155–175.

17.

Dourado

, Mograbi

, Santos

, et al. Awareness of disease in dementia: Factor structure of the Assessment Scale of Psychosocial Impact of the Diagnosis of Dementia. J Alzheimers Dis 2014; 41: 947–956.

18.

Samanez-Larkin

and Knutson

. Decision making in the aging brain: Changes in affective and motivational circuits. Nat Rev Neurosci 2015; 16: 278–289.

19.

Maki

, Amari

, Yamaguchi

, et al. Anosognosia. Am J Alzheimers Dis Other Demen 2015; 27: 339–345.

20.

Lacerda

, Santos

, Neto

JPS

, et al. Factors related to different objects of awareness in Alzheimer disease. Alzheimer Dis Assoc Disord 2017; 31: 335–312.

21.

Gambina

, Bonazzi

, Valbusa

, et al. Awareness of cognitive deficits and clinical competence in mild to moderate Alzheimer's disease: Their relevance in clinical practice. Neurol Sci 2014; 34: 385–390.

22.

Consentino

, Metcalfe

, Cary

, et al. Memory awareness influences everyday decision-making capacity about medication management in Alzheimer’s disease. Int J Alzheimers Dis 2011; 48: 389.

23.

van Vliet

, de Vugt

, Köhler

, et al. Awareness and its association with affective symptoms in young-onset and late-onset. Alzheimer disease. Alzheimer Dis Assoc Disord 2013; 27: 265–271.

24.

Maia

, Godinho

, Ferreira

, et al. Application of the Brazilian version of the CDR scale in samples of dementia patients. Arq Neuropsiquiatr 2006; 64: 485–489.

25.

Bertolucci

, Brucki

, Campacci

, et al. O Mini-Exame do Estado Mental em uma população geral: Impacto da escolaridade. Arq Neuropsiquiatr 1994; 51: 01–07.

26.

Grisso

, Appelbaum

and Hill-Fotouhi

. The MacCAT-T: A clinical tool to assess patients’ capacities to make treatment decisions. Psychiatr Serv 1997; 48: 1415–1419.

27.

Dutra

, Ribeiro

RDS

, Pinheiro

, et al. Accuracy and reliability of the Pfeffer Questionnaire for the Brazilian elderly population. Dement Neuropsychol 2015; 9: 176–183.

28.

Alexopoulos

, Abrams

, Young

, et al. Cornell scale for depression in dementia. Biol Psychiatry 1988; 23: 271–284.

29.

Portugal

, Coutinho

ESF

, Almeida

, et al. Validation of Montgomery-Asberg Rating Scale and Cornell Scale for Depression in Dementia in Brazilian elderly patients. Int Psychogeriatr 2012; 24: 1291–1298.

30.

Camazzotto

, Kochhann

, Simeoni

, et al. Reliability of the Brazilian Portuguese version of the neuropsychiatric inventory (NPI) for patients with Alzheimer's disease and their caregivers. Int Psychogeriatr 2008; 2: 383–393.

31.

Logsdon

, Gibbons

, McCurry

, et al. Assessing quality of life in older adults with cognitive impairment. Psychosom Med 2002; 3: 510–519.

32.

Novelli

, Nitrini

and Caramelli

. Validation of the Brazilian version of the quality of life scale for patients with Alzheimer's disease and their caregivers (QOL-AD). Aging Ment Health 2010; 14: 624–631.

33.

Bramham

, Morris

, Honark

, et al. Social and emotional functioning following bilateral and unilateral neurosurgical prefrontal cortex lesions. J Neuropsychol 2009; 3: 125–143.

34.

Belfort

, Bramham

, Neto

, et al. Cross-cultural adaptation of the Social and Emotional Questionnaire on Dementia for the Brazilian population. São Paulo Med J 2015; 133: 358–366.

35.

Svanberg

, Spector

and Scott

. The impact of young onset dementia on the family: A literature review. Int Psychogeriatr 2010; 23: 356–371.

36.

Baptista

MAT

, Kimura

, Lacerda

, et al. Domains of awareness in young and late onset dementia. J. Alzheimers Dis 2021; 81: 169–178.

37.

Fan

. Education and decision-making: An experimental study on the framing effect in China. Front Psychol 2017; 8: 744.

38.

Wilkins

, Locascio

, Gomez-Isla

, et al. Longitudinal changes in neuropsychiatric symptoms: Impact of discrepancy in everyday preferences between persons with cognitive impairment and their care partners. Am J Geriatr Psychiatry 2022; 30(5): 619–623.

39.

Verhey

FRJ

, Rozendaal

, Ponds

RWMH

, et al. Dementia, awareness and depression. Int J Geriatr Psychiatry 1993; 8: 851–856.

40.

Pirotte

and Benson

. Refusal to Care. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing, https://www.nbci.nlm.nih.gov/books/NBK86 (accessed 25 July 2023).