1. Introduction

Mixed/multifactorial dementia (MD) is a condition in which a person has more than one type of dementia, and for the present study, it is defined as the combination of the two most prevalent types of dementia (most frequent in the older population), namely Alzheimer’s Disease (AD) and Vascular Dementia (VaD) and seems to be more common than previously believed in the older adult population. There is a huge debate regarding the very existence of this heterogeneous disorder, namely the conceptualization and diagnosis of these two entities, and the hypothesized separate or common mechanisms underlying AD and VaD, and so far, the diagnosis of MD is considered to be a diagnostic challenge based on the clinical/neuroimaging criteria of possible AD plus cerebrovascular disease (CVD).

Due to the lack of consensus on the diagnostic criteria and the heterogeneous neuropathological characteristic of MD, this disorder has not been widely studied. Brain findings highlight the common existence of CVD lesions (e.g., lacunes and white matter lesions) in patients with AD, and typical pathological changes found in AD (e.g., extracellular amyloid plaques and intracellular neurofibrillary tangles) are frequently observed in patients with VaD, thus supporting the co-existence of similar brain mechanisms in these two diagnoses.

The fact that an older person may have a combination of two types of dementia means that symptomatology may vary. There is evidence supporting that MD is characterized by lower scores compared to AD patients. More specifically, reduced performance has been found in tests examining basic cognitive domains such as attention, memory, denomination, visuo-construction tasks, and spatial abilities, as well as executive functions among patients with MD of mild to moderate severity compared to patients with similar AD severity as those with a diagnosis of AD reported in an additional study.

One area of focus regarding Instrumental Activities of Daily Living (IADLs), which is of extreme importance for the older population, is financial capacity. Financial capacity is considered to be a broad and complex psychological construct that includes a variety of activities and specific skills (e.g., arithmetic counting coins/currency, paying bills, etc.) and judgment-decision-making skills. Deficits in financial capacity performance have been found in older patients with a diagnosis of VaD, AD, Parkinson’s Disease with Dementia (PDD), and in amnestic Mild Cognitive Impairment (aMCI). It is of interest that in the abovementioned groups of patients, the existence of comorbid depressive symptomatology clearly deteriorates further financial performance.

In addition to that, research has shown deficits in arithmetic and financial problems, which are included in instruments measuring financial capacity per se in patients suffering from fronto-temporal dementia (FTD), and relevant self-overestimations were also reported by the patients regarding their financial performance. This distorted self-awareness (overestimation) is also detected in MCI patients, in mild and moderate AD patients, Parkinson’s disease patients, and in patients with Lewy Body Dementia (LBD).

While the research on financial capacity and old age is still emerging, patients with a diagnosis of MD have been largely neglected. So far, only one study has shown that individuals with MD without depressive symptomatology demonstrate similar financial capacity performance with AD patients without depression and similar Mini-Mental State Examination (MMSE) scores.

Biologically, brain areas such as the medial frontal and anterior temporal cortices’ decreased activity are related to impaired self-awareness in AD patients, and inaccurate self-evaluations of cognitive domains, such as memory which is involved in financial capacity performance are controlled by the prefrontal cortex. Of relevant interest is also the atrophy in the frontal and parietal lobes and, more specifically, the angular gyrus in the left parietal lobe in MCI (MCI) as well as in mild AD patients.

Given all the above brain areas, which are not only affected in AD and MCI, but in many cases of MD patients, the aim of this research is to examine for the first time financial capacity performance in MD patients, and more specifically in MD patients with or without comorbid depressive symptomatology compared to healthy older adults with and without depression.

2. Materials and Methods

In the current study, 115 Greek older adults (n = 74 women; n = 41 men) were recruited from the Memory Clinic of Papanikolaou General Hospital and the Greek Alzheimer Association of Alzheimer’s Disease and Related Disorders (GAADRD), Thessaloniki, Greece. The diagnoses of the patients were supported by a consensus of specialized neurologists, geriatric psychiatrists, and neuropsychologists after neurological examination and neuropsychological assessment, medical history, neuroimaging (CT and/or MRI), and blood tests. Thirty participants had a diagnosis of MD (n = 16 women; n = 14 men) characterized as moderate cognitive impairment (based on Mini-Mental State Examination (MMSE) scores), with no depressive symptomatology present based on a useful self-report tool used worldwide as well as in the Greek older population with a cutoff score of 6–7 points; the 15-item Geriatric Depression Scale (GDS-15) score for all included participants was <6 (M_GDS-15 = 1.70; SD = 1.51). A total of 25 participants had a diagnosis of moderate MD with depressive symptomatology (n = 13 women; n = 12 men) according to their self-reported depressive symptomatology (M_GDS-15 = 9.84, SD = 2.77).

A total of 30 community-dwelling older adults (n = 23 women; n = 7 men) (M_GDS-15 = 0.56, SD = 1.27), with no diagnosis related to cognitive deficits and with GDS-15 scores < 6, were approached following purposeful sampling (regarding their gender, age, and education characteristics) and were also tested as a control group. In addition to that, 30 older patients suffering only from depression (n = 22 women; n = 8 men) were also tested (M_GDS-15 = 10.10, SD = 1.84).

Regarding the two groups characterized as MD depressed and solely depressed, at least two of the following criteria had to be met, following similar previous studies): (1) self-reported active depression in the last two years, (2) depression/dysphoria symptoms as reported on the Neuropsychiatric Inventory Questionnaire (NPI-Q), (3) clinically depressed mood based on clinician interview, (4) a GDS-15 score of at least six, and (5) depressive symptomatology reported by the participants’ family or other people (caregivers, healthcare experts, friends) for a maximum of 12 months period.

Healthy controls were matched with the patient groups (MD, MD depressed, and only depressed individuals) regarding age [F(3, 110) = 1.363, p = 0.258], years of education [F(3, 110) = 0.356, p = 0.785], and gender [χ²(3) = 6.685, p = 0.083] (see Table 1).

Participants in all four groups were excluded as in similar studies if the following criteria were present: a history of substance abuse, previous traumatic brain injury (TBI) and related neurosurgical interventions, concomitant serious medical illness (significant visual and/or auditory impairment not corrected sufficiently by visual/auditory aids), a history of other neurologic or psychiatric disorder that may interfere with the patient’s neuropsychological performance. For the MD group, 1 individual was excluded; for the MD group with depressive symptomatology, 2 individuals were excluded; for the group with a diagnosis of depression, 1 individual was excluded; for the healthy group, 1 individual was excluded (their scores are not presented and not included in the final analyses of this paper).

An extensive neuropsychological test battery was administered in order to assist in diagnosis by assessing basic cognitive abilities such as attention, working memory, abstraction, inhibition, fluency, verbal learning and memory, visual memory, visuospatial skills, and psychomotor speed. These tests were the Mini-Mental State Examination (MMSE), Test of Everyday Attention (ΤΕA), Trail Making Test (TMT)-Parts A and B, Rey-Osterrieth Complex Figure Test (ROCF)-copy condition and immediate and delayed recall conditions of the complex design, Rey Auditory Verbal Learning Test (RAVLT), Rivermead Behavioural Memory Test (RBMT), Verbal Fluency Task, Neuropsychiatric Inventory (NPI), Instrumental Activities of Daily Living (ΙADL), Clinical Dementia Rating (CDR), and Functional-Cognitive Assessment Scale (FUCAS). Financial capacity was assessed with the Legal Capacity for Property Law Transactions Assessment Scale (LCPLTAS), which consists of seven main domains: basic monetary skills, cash transactions, bank statement management, bill payment, financial conceptual knowledge, financial decision-making, and knowledge of personal assets. LCPLTAS is based on the Financial Capacity Instrument introduced by Marson and follows the same conceptual framework. More specifically, older adults are asked to complete a number of tasks ranging from simple tasks (such as naming coins, performing basic mathematical operations, defining verbally financial concepts, and making statements about their personal assets) to more complex ones (such as deciding on hypothetical financial scenarios and explaining their thinking steps and relevant decision-making). All participants were examined during the same semester (during the period from October 2013 to March 2014). There was only one version of LCPLTAS administered at one time point by the same neuropsychologist. Neuropsychological testing took place individually for each participant at the same location (a quiet soundproof room without distracting stimuli), and for all participants, evaluations were conducted during morning hours.

All participants provided written informed consent prior to study participation and were not compensated for their participation in the study. They agreed to participate voluntarily and that they could withdraw their participation at any time without providing any reason and without any cost. The study protocol was approved by the Ethics Committee of the Aristotle University of Thessaloniki (as part of a larger study) and followed the declaration of Helsinki.

Statistical Analysis

Statistical analysis was performed with the SPSS (IBM Corp (2016) IBM SPSS Statistics for Windows (Version 24)). Descriptive statistics and one-way analyses of variance (ANOVAs) were conducted to examine possible differences in demographic factors and cognitive test scores of the four groups (MD patients, patients with MD and comorbid depression, healthy controls, and patients diagnosed only with depression). In addition, Pearson’s correlations between MMSE (as this has been found to be one of the best correlates of LCPTLAS in prior research) and LCPTLAS were performed. Post-hoc Tamhane’s T2 are presented in order to explore significant differences, and the effect size of the differences was measured with eta squared. Probability values < 0.05 (two-tailed) were considered statistically significant.

3. Results

A strong positive correlation was found between the MMSE score and the LCPTLAS for the whole sample (r = 0.958, p < 0.001). This indicates that high MMSE scores (which reflect high cognitive ability) correlate in a statistically significant way with high scores on LCPTLAS, which depicts high financial ability. For the whole sample, no other statistically significant correlation was found between LCPTLAS and education (in years) (r = 0.089, p = 0.348) as well as for LCPTLAS and age (in years) (r = 0.061, p = 0.520).

One-way ANOVA revealed (as expected) significant differences and large effect sizes for the MMSE scores (F(3, 108) = 140.398, p < 0.001, η² = 0.768). Comparisons following one-way ANOVA for financial capacity as examined by LCPTLAS showed statistically significant differences with the healthy controls without depression performing best, followed by patients suffering only from depression, moderate MD patients without depression, and MD patients with depression (F(3, 110) = 181.391, p < 0.001, η² = 0.831) (see Table 1).

Table 1. Demographics, MMSE, GDS-15, and LCPTLAS scores for the four groups.

4. Discussion

The above findings provide support for the first time for a significant impairment in financial capacity in cases of dual mixed pathology, such as MD (AD + vascular) with comorbid depression. The current study investigated performance in MD patients with and without comorbid depressive symptomatology and supports that both diagnostic groups are characterized by financial incapacity and that both groups clearly differentiate from non-depressed matched participants. Age (in years) and educational level (in years) of participants were not found to correlate with financial performance in LCPTLAS in this sample. This is in contrast to previous findings in healthy aging that support a negative influence of advancing age on financial capacity, as well as findings regarding education and the fact that a lower educational level negatively affects financial capacity performance in MCI patients. Nevertheless, the current results confirm previous findings regarding the negative influence of depression on financial capacity performance in other groups of older adults suffering from neurocognitive disorders, such as PDD, VD, and MCI. It is of interest that this detrimental influence of depressive symptomatology is corroborated not only by linear analyses but also by advanced statistical methods based on catastrophe theory (nonlinear models) for the elder population. This negative influence has also been supported in longitudinal designs measuring depression levels at different time points, a finding that is for the first time supported in this cross-sectional study of MD patients. In addition to that, the finding of a strong positive correlation between MMSE and LCPTLAS highlights the importance of MMSE scores as relevant to financial capacity assessments.

This is an interesting point as both the MMSE as well as the specifically designed tool for financial capacity assessment (LCPTLAS) could both be used as neuropsychological indicators that are easy to administer and act as important sources of information for everyday functioning as well as sources to build personalized interventions against financial abuse in older adult populations.

Although the current study has several strengths, such as the exclusion of demographic influences that could play the role of confounders, this study also presents some limitations, which should be taken into consideration in future research endeavors, such as the small sample size, the slightly unequal size of the subgroups, and the fact that demented patients were not examined with post mortem autopsy (so the exact brain pathology could be documented in detail). Additionally, variables such as previous stressful life events or prior high levels of depression, the behavioral and psychological symptoms of dementia (BPSD), genetic information about the participants (e.g., APOE e4), as well as the simultaneous administration and use of scores coming from other financial capacity instruments were not entered into the analyses.

5. Conclusions

This is the first ever reported study of its kind to show that depression has a clearly differentiating power on financial capacity performance in the group of moderate MD patients. Although none of the participants was characterized as legally incapacitated, thus, officially, there was no legal decision depriving them of their right to make financial decisions, for both groups of MD and MD depressed patients, their family members responded that they unofficially made all relevant financial decisions on behalf of the older adults, something that corroborates the general tendency in Greece to consider as stigma the durable power of attorney for financial decisions, the valid wills as well as the living wills of older adults. Of course, having caregivers make financial decisions for MD patients seems to be a solution, but this is done unofficially as the caregivers were not appointed by the court and, thus, they are not legal guardians, something that still renders older people vulnerable to financial exploitation. Given that financial capacity deficits in MD patients should not be underestimated, future research should focus on unraveling the neurobiological substrate of financial incapacity when depression is present in MD. Furthermore, healthcare professionals should be aware of the financial effects of dementia and depression, and although they are not trained in financial management, they can still inform caregivers so they can make changes by taking over the financial affairs of older adult patients only after being officially determined by a court as legally incapacitated for financial decision-making.

Introduction

Mixed dementia (MD) is a condition in which an individual has more than one type of dementia. For the purpose of this study, MD is defined as the combination of Alzheimer’s Disease (AD) and Vascular Dementia (VaD), the two most common types in older adults. The prevalence of MD in older populations appears to be higher than previously estimated. There is ongoing debate regarding the nature of this complex disorder, specifically concerning the conceptualization and diagnosis of AD and VaD, as well as whether they involve separate or shared underlying mechanisms. Currently, diagnosing MD presents a challenge, primarily relying on clinical and neuroimaging criteria that suggest possible AD alongside cerebrovascular disease (CVD).

The lack of consistent diagnostic criteria and the diverse neuropathological characteristics of MD have limited extensive research on this disorder. Brain studies frequently reveal the co-occurrence of CVD lesions, such as lacunes and white matter lesions, in patients with AD. Conversely, typical pathological changes seen in AD, like extracellular amyloid plaques and intracellular neurofibrillary tangles, are often observed in patients with VaD. These findings support the notion that similar brain mechanisms may contribute to both diagnoses.

The co-occurrence of two types of dementia in an older person can result in varied symptomatology. Evidence suggests that individuals with MD often exhibit lower cognitive scores compared to those with AD. Specifically, reduced performance has been noted in fundamental cognitive areas such as attention, memory, naming, visuo-construction, spatial abilities, and executive functions among patients with mild to moderate MD severity, even when compared to AD patients of similar severity.

A crucial aspect of Instrumental Activities of Daily Living (IADLs) for older adults is financial capacity. This is a broad and intricate psychological construct encompassing a range of activities and specific skills, including arithmetic operations, managing currency, paying bills, and making sound judgments and decisions. Deficits in financial capacity have been identified in older patients diagnosed with VaD, AD, Parkinson’s Disease with Dementia (PDD), and amnestic Mild Cognitive Impairment (aMCI). Notably, the presence of co-occurring depressive symptoms in these patient groups distinctly exacerbates financial performance. Research has also indicated deficits in arithmetic and financial problem-solving in patients with fronto-temporal dementia (FTD), who sometimes overestimate their financial abilities. This distorted self-awareness or overestimation has also been detected in patients with MCI, mild and moderate AD, Parkinson’s disease, and Lewy Body Dementia (LBD).

Despite the emerging research on financial capacity in older age, individuals with a diagnosis of MD have been largely overlooked in this area. To date, only one study has indicated that individuals with MD who do not experience depressive symptoms exhibit financial capacity performance similar to that of AD patients without depression, alongside comparable Mini-Mental State Examination (MMSE) scores. From a biological perspective, decreased activity in brain areas such as the medial frontal and anterior temporal cortices has been linked to impaired self-awareness in AD patients. Inaccurate self-evaluations of cognitive domains, including memory, which is integral to financial capacity, are regulated by the prefrontal cortex. Atrophy in the frontal and parietal lobes, particularly the angular gyrus in the left parietal lobe, has also been observed in MCI and mild AD patients. Considering that these brain regions are affected in AD, MCI, and frequently in MD patients, the present study aimed to conduct the first examination of financial capacity performance in MD patients, specifically comparing those with and without comorbid depressive symptomatology to healthy older adults with and without depression.

Materials and Methods

The current study recruited 115 Greek older adults (74 women; 41 men) from the Memory Clinic of Papanikolaou General Hospital and the Greek Alzheimer Association of Alzheimer’s Disease and Related Disorders (GAADRD) in Thessaloniki, Greece. Patient diagnoses were confirmed by a consensus of specialized neurologists, geriatric psychiatrists, and neuropsychologists, based on neurological examination, neuropsychological assessment, medical history, neuroimaging (CT and/or MRI), and blood tests. Thirty participants received a diagnosis of moderate MD without depressive symptomatology (16 women; 14 men), exhibiting Mini-Mental State Examination (MMSE) scores indicating moderate cognitive impairment and Geriatric Depression Scale (GDS-15) scores below 6 (M_GDS-15 = 1.70; SD = 1.51). An additional 25 participants were diagnosed with moderate MD with depressive symptomatology (13 women; 12 men), characterized by self-reported depressive symptoms (M_GDS-15 = 9.84, SD = 2.77). For comparison, 30 community-dwelling older adults (23 women; 7 men) without cognitive deficits and GDS-15 scores below 6 (M_GDS-15 = 0.56, SD = 1.27) were recruited as a control group. Additionally, 30 older patients diagnosed solely with depression (22 women; 8 men) were included (M_GDS-15 = 10.10, SD = 1.84). Criteria for the MD depressed and solely depressed groups included self-reported active depression, depressive symptoms on the Neuropsychiatric Inventory Questionnaire (NPI-Q), clinically depressed mood, a GDS-15 score of at least six, or caregiver reports of depressive symptomatology. Healthy controls were matched with patient groups based on age, years of education, and gender. Participants were excluded if they had a history of substance use, traumatic brain injury, related neurosurgical interventions, significant uncorrected visual or auditory impairment, or other neurological or psychiatric disorders that could interfere with neuropsychological performance. One individual was excluded from the MD group, two from the MD with depressive symptomatology group, one from the depression-only group, and one from the healthy control group.

A comprehensive neuropsychological test battery was administered to aid in diagnosis by evaluating fundamental cognitive abilities such as attention, working memory, abstraction, inhibition, fluency, verbal learning and memory, visual memory, visuospatial skills, and psychomotor speed. These tests included the Mini-Mental State Examination (MMSE), Test of Everyday Attention (TEA), Trail Making Test (TMT)-Parts A and B, Rey-Osterrieth Complex Figure Test (ROCF)-copy condition and immediate and delayed recall, Rey Auditory Verbal Learning Test (RAVLT), Rivermead Behavioural Memory Test (RBMT), Verbal Fluency Task, Neuropsychiatric Inventory (NPI), Instrumental Activities of Daily Living (IADL), Clinical Dementia Rating (CDR), and Functional-Cognitive Assessment Scale (FUCAS).

Financial capacity was assessed using the Legal Capacity for Property Law Transactions Assessment Scale (LCPLTAS), which comprises seven primary domains: basic monetary skills, cash transactions, bank statement management, bill payment, financial conceptual knowledge, financial decision-making, and knowledge of personal assets. The LCPLTAS, conceptually aligned with Marson’s Financial Capacity Instrument, required participants to complete tasks ranging from simple (e.g., naming coins, basic math, defining financial concepts, stating personal assets) to complex (e.g., making decisions on hypothetical financial scenarios and explaining reasoning). All participants were examined individually by the same neuropsychologist in a quiet, soundproof room during morning hours over a single semester (October 2013 to March 2014), using a single version of the LCPLTAS.

All participants provided written informed consent prior to participating in the study and did so voluntarily without compensation. They were informed of their right to withdraw at any time without consequence. The study protocol received approval from the Ethics Committee of the Aristotle University of Thessaloniki and adhered to the Declaration of Helsinki. Statistical analysis was conducted using SPSS (IBM Corp (2016) IBM SPSS Statistics for Windows (Version 24)). Descriptive statistics and one-way analyses of variance (ANOVAs) were performed to examine group differences in demographic factors and cognitive test scores. Pearson’s correlations between MMSE and LCPLTAS scores were also calculated. Post-hoc Tamhane’s T2 tests were used to explore significant differences, with effect sizes measured by eta squared. Probability values below 0.05 (two-tailed) were considered statistically significant.

Results

A strong positive correlation was observed between Mini-Mental State Examination (MMSE) scores and Legal Capacity for Property Law Transactions Assessment Scale (LCPLTAS) scores across the entire sample (r = 0.958, p < 0.001). This indicates that higher MMSE scores, reflecting greater cognitive ability, were significantly associated with higher scores on the LCPLTAS, representing better financial capacity. No other statistically significant correlations were found between LCPLTAS scores and participants’ years of education (r = 0.089, p = 0.348) or age (r = 0.061, p = 0.520) for the whole sample.

One-way analyses of variance (ANOVAs) revealed significant differences and large effect sizes for MMSE scores among the groups (F(3, 108) = 140.398, p < 0.001, η2 = 0.768). Comparisons for financial capacity, as assessed by the LCPLTAS, also showed statistically significant differences (F(3, 110) = 181.391, p < 0.001, η2 = 0.831). Healthy controls without depression performed best, followed by patients suffering only from depression, then moderate Mixed Dementia (MD) patients without depression, and finally, MD patients with depression demonstrated the lowest financial capacity.

Discussion

The findings of this study provide the first evidence of significant impairment in financial capacity in cases of dual mixed pathology, specifically Mixed Dementia (MD) involving Alzheimer’s Disease and vascular components, particularly when comorbid depression is present. The study indicates that both MD diagnostic groups (with and without depression) are characterized by financial incapacity and clearly differ from non-depressed matched participants. Unlike some previous findings in healthy aging and Mild Cognitive Impairment (MCI), this sample did not show correlations between financial performance on the LCPLTAS and participants’ age or educational level. However, the current results corroborate previous findings concerning the negative influence of depression on financial capacity performance in other groups of older adults with neurocognitive disorders, such as Parkinson’s Disease with Dementia (PDD), Vascular Dementia (VaD), and MCI. This detrimental influence of depressive symptomatology has been supported by both linear and nonlinear analytical methods in the elderly population and in longitudinal designs measuring depression levels over time, a finding now supported for the first time in this cross-sectional study of MD patients. Furthermore, the strong positive correlation observed between MMSE and LCPLTAS highlights the importance of MMSE scores in assessments of financial capacity.

This strong correlation suggests that both the MMSE and the specialized financial capacity assessment tool, LCPLTAS, could serve as valuable and easily administered neuropsychological indicators. They can provide important information for understanding an individual's everyday functioning and can inform the development of personalized interventions aimed at preventing financial abuse in older adult populations.

While the study has several strengths, such as the rigorous exclusion of demographic influences that could act as confounding variables, it also presents certain limitations that should be considered in future research endeavors. These limitations include the relatively small sample size and the slightly unequal sizes of the subgroups. Additionally, the demented patients were not examined with post-mortem autopsy, which would have provided detailed documentation of the exact brain pathology. Other variables not included in the analyses were previous stressful life events, prior high levels of depression, the behavioral and psychological symptoms of dementia (BPSD), genetic information about the participants (e.g., APOE e4 status), and scores from other financial capacity instruments.

Conclusions

This pioneering study is the first to demonstrate that depression significantly differentiates financial capacity performance within the group of moderate Mixed Dementia (MD) patients. Although none of the participants were legally declared incapacitated, meaning no official legal decision deprived them of their right to make financial decisions, their family members consistently reported unofficially managing all relevant financial decisions on behalf of the older adults. This practice reflects a general tendency in Greece to view formal legal instruments, such as durable power of attorney for financial decisions, valid wills, and living wills, as stigmatizing. While caregivers making financial decisions for MD patients may seem to offer a solution, these unofficial arrangements lack court appointment or legal guardianship, which still leaves older individuals vulnerable to financial exploitation. Given that financial capacity deficits in MD patients should not be underestimated, future research should focus on elucidating the neurobiological basis of financial incapacity, especially when depression is present in MD. Furthermore, healthcare professionals should be aware of the financial implications of dementia and depression. Although not trained in financial management, they can still provide crucial information to caregivers, empowering them to pursue official court-determined legal avenues for managing the financial affairs of older adult patients, rather than relying on unofficial arrangements.

Introduction

Mixed/multifactorial dementia (MD) occurs when an individual experiences more than one type of dementia. In the context of this study, MD refers to a combination of Alzheimer's Disease (AD) and Vascular Dementia (VaD), which are the most common types in older adults. While MD appears more prevalent than previously thought, its existence, definition, and diagnostic criteria are debated, partly due to uncertainties about whether AD and VaD share common underlying biological mechanisms. Diagnosing MD remains a challenge, typically based on clinical signs of possible AD combined with evidence of cerebrovascular disease (CVD). Despite these challenges, brain studies frequently observe CVD lesions in individuals with AD, and characteristic AD changes like amyloid plaques and neurofibrillary tangles are often found in those with VaD, suggesting shared brain mechanisms.

The lack of consistent diagnostic criteria and the varied neuropathological characteristics of MD have limited extensive research into this condition. When an older adult has a combination of two dementia types, their symptoms can vary. Evidence indicates that individuals with MD often score lower on cognitive tests compared to those with AD alone. Specifically, MD patients with mild to moderate severity have shown reduced performance in basic cognitive areas such as attention, memory, naming, visual-construction tasks, spatial abilities, and executive functions when compared to AD patients of similar severity.

Instrumental Activities of Daily Living (IADLs) are crucial for older adults, with financial capacity being a particularly important area of focus. Financial capacity is a broad and intricate psychological concept encompassing various activities and skills, including basic arithmetic, handling money, paying bills, and making sound financial judgments. Deficits in financial capacity have been observed in older patients diagnosed with VaD, AD, Parkinson’s Disease with Dementia (PDD), and amnestic Mild Cognitive Impairment (aMCI). Notably, the presence of co-occurring depressive symptoms in these patient groups significantly worsens their financial performance. Research also indicates deficits in arithmetic and financial problem-solving in patients with fronto-temporal dementia (FTD), who sometimes overestimate their financial abilities. This distorted self-awareness (overestimation) is also seen in patients with MCI, mild and moderate AD, Parkinson's disease, and Lewy Body Dementia (LBD).

While research on financial capacity in older age is developing, individuals with MD have been largely overlooked in this area. To date, only one study has indicated that individuals with MD who do not have depressive symptoms exhibit financial capacity similar to AD patients without depression, given comparable Mini-Mental State Examination (MMSE) scores.

From a biological perspective, decreased activity in brain regions such as the medial frontal and anterior temporal cortices is associated with impaired self-awareness in AD patients. Inaccurate self-evaluations of cognitive domains, like memory, which is essential for financial capacity, are regulated by the prefrontal cortex. Atrophy in the frontal and parietal lobes, especially the angular gyrus in the left parietal lobe, is also relevant and observed in MCI and mild AD patients. Considering that these brain areas are affected in AD, MCI, and often in MD patients, this research aimed to be the first to examine financial capacity performance in MD patients, specifically comparing those with and without comorbid depressive symptoms to healthy older adults with and without depression.

Materials and Methods

The study recruited 115 Greek older adults (74 women, 41 men) from a Memory Clinic and the Greek Alzheimer Association in Thessaloniki, Greece. Patient diagnoses were confirmed through a consensus among specialized neurologists, geriatric psychiatrists, and neuropsychologists, based on neurological examinations, neuropsychological assessments, medical history, neuroimaging (CT and/or MRI), and blood tests. Thirty participants received a diagnosis of moderate MD without depressive symptoms, indicated by a Geriatric Depression Scale (GDS-15) score below 6. An additional 25 participants were diagnosed with moderate MD with depressive symptoms, with a mean GDS-15 score of 9.84.

The study also included two control groups: 30 community-dwelling healthy older adults (23 women, 7 men) with no diagnosed cognitive deficits and GDS-15 scores below 6, selected to match patient groups by gender, age, and education. Furthermore, 30 older patients diagnosed solely with depression (22 women, 8 men) were included, with a mean GDS-15 score of 10.10. For individuals in the MD depressed and solely depressed groups, at least two of the following criteria had to be met: self-reported active depression in the past two years, depression/dysphoria symptoms on the Neuropsychiatric Inventory Questionnaire (NPI-Q), clinically depressed mood based on interview, a GDS-15 score of at least six, or depressive symptoms reported by family/caregivers for up to 12 months.

Participants across all four groups were carefully matched for age, years of education, and gender. Exclusion criteria included a history of substance use, previous traumatic brain injury (TBI) and related neurosurgical interventions, significant uncorrected visual or auditory impairment, or any other neurological or psychiatric disorder that might interfere with neuropsychological performance. One individual was excluded from the MD group, two from the MD with depressive symptomatology group, one from the depression-only group, and one from the healthy control group, with their data removed from final analyses.

An extensive battery of neuropsychological tests was administered to assess basic cognitive abilities such as attention, working memory, abstraction, inhibition, fluency, verbal learning and memory, visual memory, visuospatial skills, and psychomotor speed. These tests included the Mini-Mental State Examination (MMSE), Test of Everyday Attention (TEA), Trail Making Test (TMT)-Parts A and B, Rey-Osterrieth Complex Figure Test (ROCF), Rey Auditory Verbal Learning Test (RAVLT), Rivermead Behavioural Memory Test (RBMT), Verbal Fluency Task, Neuropsychiatric Inventory (NPI), Instrumental Activities of Daily Living (IADL), Clinical Dementia Rating (CDR), and Functional-Cognitive Assessment Scale (FUCAS). Financial capacity was evaluated using the Legal Capacity for Property Law Transactions Assessment Scale (LCPLTAS), which assesses seven key domains: basic monetary skills, cash transactions, bank statement management, bill payment, financial conceptual knowledge, financial decision-making, and knowledge of personal assets. Participants completed tasks ranging from simple (e.g., naming coins, basic math) to complex (e.g., hypothetical financial scenarios). All evaluations were conducted individually by the same neuropsychologist in a quiet, soundproof room during morning hours, between October 2013 and March 2014. All participants provided written informed consent and participated voluntarily without compensation, with the study protocol approved by the Ethics Committee of the Aristotle University of Thessaloniki, adhering to the Declaration of Helsinki.

Statistical analysis was performed using SPSS software. Descriptive statistics and one-way analyses of variance (ANOVAs) were used to examine potential differences in demographic factors and cognitive test scores among the four groups. Pearson’s correlations were conducted between MMSE and LCPTLAS scores, as MMSE has previously been identified as a strong correlate of LCPLTAS. Post-hoc Tamhane’s T2 tests were applied to explore significant differences, with effect sizes measured using eta squared. A probability value of less than 0.05 (two-tailed) was considered statistically significant.

Results

A strong positive correlation was observed between the Mini-Mental State Examination (MMSE) score and the Legal Capacity for Property Law Transactions Assessment Scale (LCPTLAS) score across the entire study sample (r = 0.958, p < 0.001). This finding indicates that higher MMSE scores, reflecting better overall cognitive ability, are significantly associated with higher LCPTLAS scores, which represent greater financial capacity. Conversely, no statistically significant correlations were found between LCPTLAS scores and either years of education (r = 0.089, p = 0.348) or age in years (r = 0.061, p = 0.520) for the overall sample.

One-way ANOVA revealed expected significant differences with large effect sizes for MMSE scores across the four groups (F(3, 108) = 140.398, p < 0.001, η2 = 0.768). Similar statistically significant differences were found for financial capacity as assessed by LCPTLAS (F(3, 110) = 181.391, p < 0.001, η2 = 0.831). Healthy controls without depression performed the best, followed by patients suffering only from depression, then moderate MD patients without depression, and finally MD patients with depression demonstrating the lowest financial capacity scores.

Table 1. Demographics, MMSE, GDS-15, and LCPTLAS scores for the four groups.

Discussion

The study's findings provide the first evidence of significant impairment in financial capacity in cases of dual mixed dementia pathology, specifically mixed dementia (AD + vascular dementia) with comorbid depression. The research demonstrated that both the MD patient group and the MD patient group with depressive symptoms exhibited financial incapacity, and both groups clearly differed from matched participants without depression. Contrary to some previous research on healthy aging and MCI patients, the age and educational level of participants in this sample did not correlate with financial performance on the LCPTLAS. However, these results affirm prior findings regarding the negative impact of depression on financial capacity in other groups of older adults with neurocognitive disorders, such as Parkinson’s Disease with Dementia, Vascular Dementia, and Mild Cognitive Impairment. This detrimental effect of depressive symptoms is supported by various analytical methods, including linear and non-linear models, and has been observed in longitudinal studies; this cross-sectional study now supports this influence for MD patients. Furthermore, the strong positive correlation between MMSE and LCPTLAS scores underscores the importance of MMSE as a relevant indicator in financial capacity assessments. Both the MMSE and the specialized financial capacity tool (LCPLTAS) can serve as easily administered neuropsychological indicators, providing valuable insights into daily functioning and offering essential information for developing personalized interventions against financial abuse in older adult populations.

Despite several strengths, such as controlling for demographic influences that could act as confounding variables, the study has limitations. These include a relatively small sample size, slightly unequal subgroup sizes, and the absence of post-mortem autopsy examinations to confirm precise brain pathology. Additionally, variables such as past stressful life events, prior high levels of depression, behavioral and psychological symptoms of dementia (BPSD), genetic information (e.g., APOE e4), and the concurrent use of scores from other financial capacity instruments were not included in the analyses. Future research should address these limitations to build upon the current findings.

Conclusions

This study is the first of its kind to demonstrate that depression significantly differentiates financial capacity performance within the group of moderate mixed dementia patients. Although none of the participants were formally deemed legally incapacitated, their family members reported informally managing all relevant financial decisions for the older adults. This informal approach reflects a common tendency in Greece to view formal legal instruments like durable powers of attorney or valid wills as stigmatizing. While caregivers making financial decisions for MD patients may seem practical, performing these actions unofficially without formal legal guardianship leaves older individuals vulnerable to financial exploitation. Given that financial capacity deficits in MD patients should not be underestimated, future research needs to explore the neurobiological underpinnings of financial incapacity when depression co-occurs with MD. Healthcare professionals, even if not trained in financial management, should inform caregivers about the financial implications of dementia and depression, advising them to seek official court determination of legal incapacity before taking over financial affairs for older adult patients.

Introduction

Mixed dementia (MD) describes a condition where an individual experiences more than one type of dementia. For this study, it refers to the combination of Alzheimer's Disease (AD) and Vascular Dementia (VaD), which are the most common types of dementia in older adults. This combination appears to be more widespread than previously thought. The existence, diagnosis, and underlying causes of MD are often debated, and diagnosing it remains a challenge based on current clinical and brain imaging criteria.

Due to the lack of clear diagnostic guidelines and the varied brain changes seen in MD, this condition has not been widely studied. Brain research often shows that individuals with AD also have signs of cerebrovascular disease (CVD), such as small brain lesions. Similarly, individuals with VaD often show typical changes associated with AD, like amyloid plaques and neurofibrillary tangles. These findings suggest that similar brain processes may be at work in both diagnoses.

The presence of two types of dementia can lead to varied symptoms. Research indicates that individuals with MD often score lower on cognitive tests compared to those with AD. Specifically, they may show reduced performance in basic mental skills like attention, memory, naming objects, visual-spatial tasks, and executive functions, even in mild to moderate stages of the disease.

A critical aspect of daily living for older adults is financial capacity. This complex skill involves various activities, such as counting money, paying bills, and making sound financial judgments. Deficits in financial capacity have been observed in older individuals diagnosed with VaD, AD, Parkinson's Disease with Dementia (PDD), and mild cognitive impairment (aMCI). Notably, the presence of depression in these groups can further worsen financial performance.

Research also shows that individuals with frontotemporal dementia (FTD) struggle with arithmetic and financial problems. They may also overestimate their own financial abilities. This distorted self-awareness (overestimation) has also been noted in patients with mild cognitive impairment, mild and moderate AD, Parkinson's disease, and Lewy Body Dementia (LBD). Despite its importance, financial capacity in MD patients has largely been overlooked in research. Only one study so far has compared financial capacity in MD patients without depression to AD patients without depression, finding similar performance.

Certain brain areas, such as the medial frontal and anterior temporal cortices, show decreased activity in AD patients, which is linked to impaired self-awareness. The prefrontal cortex controls accurate self-evaluations of cognitive skills, including memory, which is vital for financial capacity. Additionally, atrophy (shrinkage) in the frontal and parietal lobes, particularly the angular gyrus in the left parietal lobe, has been observed in individuals with mild cognitive impairment and mild AD. Given that these brain areas are affected in many cases of MD, this research aimed to be the first to examine financial capacity in MD patients, specifically comparing those with and without depression to healthy older adults with and without depression.

Materials and Methods

This study involved 115 Greek older adults, recruited from a Memory Clinic and the Greek Alzheimer Association. Specialized neurologists, geriatric psychiatrists, and neuropsychologists confirmed patient diagnoses through neurological exams, neuropsychological assessments, medical history reviews, brain imaging, and blood tests. Thirty participants had a moderate mixed dementia diagnosis without depression, and 25 had a moderate mixed dementia diagnosis with depression.

Thirty healthy older adults from the community served as a control group, and another 30 older patients with only depression were also included. For the groups with depression, at least two specific criteria had to be met, such as self-reported depression within the last two years or a certain score on a depression scale.

Healthy controls were matched with the patient groups for age, education, and gender to ensure fair comparisons. Participants were excluded from the study if they had a history of substance use, previous traumatic brain injury, serious ongoing medical conditions, or other neurological or psychiatric disorders that could interfere with their cognitive performance. A few individuals were excluded from each group based on these criteria.

An extensive battery of neuropsychological tests was administered to assess basic cognitive abilities such as attention, memory, and problem-solving skills. Financial capacity was specifically evaluated using the Legal Capacity for Property Law Transactions Assessment Scale (LCPLTAS). This scale includes seven main areas, from basic money skills to complex financial decision-making. All participants were tested individually by the same neuropsychologist in a quiet, soundproof room during morning hours.

All participants provided written informed consent before the study and participated voluntarily without compensation. They were informed they could withdraw at any time. The study followed ethical guidelines and was approved by the Ethics Committee of the Aristotle University of Thessaloniki. Statistical analysis was performed to examine differences in demographic factors and cognitive test scores among the four groups. Researchers also looked for relationships between overall cognitive ability (MMSE scores) and financial capacity (LCPLTAS scores).

Results

A strong positive relationship was found between scores on the overall cognitive ability test (MMSE) and the financial capacity test (LCPTLAS) across the entire study group. This indicates that higher cognitive ability was significantly linked to better financial skills. However, no significant relationship was found between financial capacity and a person's age or years of education in this sample.

As expected, significant differences were observed in MMSE scores among the four groups. Comparisons of financial capacity, as measured by LCPTLAS, also showed statistically significant differences. Healthy older adults without depression performed the best, followed by patients suffering only from depression, then moderate mixed dementia (MD) patients without depression, and finally, MD patients with depression showed the lowest financial capacity.

Discussion

These findings are the first to demonstrate significant impairment in financial capacity in cases of mixed dementia (AD + vascular dementia) when combined with depression. The study revealed that both mixed dementia groups (with and without depression) showed impaired financial capacity, clearly differing from healthy participants. Unlike some previous research, this study found no link between age or education level and financial performance in this specific group. However, the results do confirm earlier findings that depression negatively impacts financial capacity in older adults with other neurocognitive disorders. This harmful effect of depression was consistently supported by the study's analyses.

The strong positive relationship found between the MMSE and LCPTLAS highlights the importance of MMSE scores for assessing financial capacity. Both the MMSE and the specialized financial capacity tool (LCPTLAS) can serve as easily administered indicators of daily functioning. They can also provide crucial information for developing personalized interventions to prevent financial abuse in older adult populations.

Despite its strengths, such as controlling for demographic influences, this study has some limitations. These include a relatively small sample size, slightly unequal subgroup sizes, and the absence of post-mortem brain autopsies to confirm exact brain pathologies. Additionally, factors such as past stressful life events, prior levels of depression, behavioral and psychological symptoms of dementia, genetic information, and scores from other financial capacity instruments were not included in the analysis.

Conclusions

This is the first study of its kind to demonstrate that depression significantly affects financial capacity performance in individuals with moderate mixed dementia. Although none of the participants were legally declared unable to manage their finances, their family members often unofficially made all relevant financial decisions on their behalf. This unofficial practice, common in Greece due to the stigma associated with legal documents like power of attorney or living wills, leaves older adults vulnerable to financial exploitation.

While caregivers unofficially managing finances for mixed dementia patients may seem like a solution, it carries risks since they are not legally appointed guardians. This situation continues to leave older individuals susceptible to financial exploitation. Given that financial capacity deficits in mixed dementia patients should not be overlooked, future research should focus on understanding the brain mechanisms behind financial incapacity when depression is present in MD. Furthermore, healthcare professionals, even without training in financial management, should inform caregivers about the financial effects of dementia and depression. They should advise caregivers to take over an older adult's financial affairs only after a court has officially declared the individual legally incapacitated for financial decision-making.

Introduction

Mixed dementia happens when a person has more than one type of dementia. This study looked at mixed dementia that combines Alzheimer's disease (AD) and Vascular Dementia (VaD). This type of mixed dementia seems to be more common in older people than once thought. However, doctors still debate how to understand and diagnose it.

It has been hard to study mixed dementia because there is no clear way to diagnose it. Brain studies show that changes often seen in VaD (like small strokes) are also common in people with AD. Also, changes often seen in AD (like amyloid plaques) are often found in people with VaD. This suggests that these two types of dementia may share similar causes in the brain.

Since an older person can have two types of dementia at once, their symptoms can be different. People with mixed dementia often score lower on memory and thinking tests compared to people who only have Alzheimer's disease. This includes problems with attention, memory, naming things, drawing, and problem-solving.

Managing money is a very important daily activity for older people. This is called financial capacity. It involves many skills, like counting money, paying bills, and making good financial choices. People with VaD, AD, and Parkinson's disease often have trouble with money. Having depression also makes these financial problems worse.

Very little research has looked at financial capacity in people with mixed dementia. This study wanted to examine financial capacity in people with mixed dementia, with and without depression. It also compared them to healthy older adults.

Materials and Methods

This study included 115 older adults from Greece. Thirty of these participants had mixed dementia without depression. Another 25 participants had mixed dementia along with depression.

For comparison, the study also included 30 healthy older adults who did not have thinking problems. Another 30 older adults who had only depression were also part of the study.

People were not included in the study if they had a history of drug abuse, head injury, serious medical problems, or other brain or mental health issues. A few people were excluded from each group based on these rules.

Many tests were given to check thinking skills like memory, attention, and problem-solving. A special test called LCPLTAS was used to measure financial capacity. This test covered basic money skills, managing bank accounts, paying bills, understanding money concepts, and making financial choices.

All participants agreed in writing to be part of the study. They were not paid and could leave the study at any time. The study followed ethical guidelines.

Results

The study found a strong link between scores on a general thinking test (MMSE) and scores on the financial capacity test (LCPLTAS). Higher scores on the thinking test meant better financial ability. The study found that age and years of education did not affect financial capacity in these participants.

As expected, there were big differences in general thinking scores among the groups. The study also found major differences in financial capacity. Healthy older adults did the best. People with only depression did next best. Then came people with mixed dementia without depression. People with mixed dementia and depression did the worst in managing money.

Discussion

This study is the first to show that having both mixed dementia and depression greatly harms a person's ability to manage money. Both groups with mixed dementia showed problems with money management, and they were clearly different from people who did not have depression. This study also found that depression makes financial problems worse for older adults, which matches what other studies have shown.

The strong link between the general thinking test (MMSE) and the financial capacity test (LCPLTAS) means both tests can help understand how well older adults manage money each day. This information can also help create special plans to protect older adults from financial abuse.

This study had good points, such as making sure age and education did not affect the results. But it also had some limits. The study included a small number of people, and the groups were not exactly the same size. Also, the study did not look at other things that might affect the results, like past stressful events or genetic information.

Conclusions

This study is the first of its kind to show that depression clearly makes a difference in the financial capacity of people with moderate mixed dementia. Even though no one in the study was legally declared unable to manage money, family members often made financial decisions for these older adults. This often happens unofficially, especially in Greece, where formal legal steps for this are not common.

It is important not to ignore financial problems in people with mixed dementia. Future studies should look more closely at how depression affects financial capacity in people with mixed dementia. Healthcare workers should also tell family members about the money problems that can come with dementia and depression. They should encourage families to get official legal power to make financial decisions for older adults when needed, to better protect them from financial harm.