Association of TDP-43 Pathology With Domain-specific Literacy in Older Persons

LATE-NC in Alzheimer's disease: Molecular aspects and synergies

Alzheimer's disease (AD) is classically characterized by senile plaques and neurofibrillary tangles (NFTs). However, multiple copathologies can be observed in the AD brain and contribute to the development of cognitive decline. Limbic-predominant age-related TDP-43 encephalopathy neuropathological changes (LATE-NC) accumulates in the majority of AD cases and leads to more severe cognitive decline compared with AD pathology alone. In this review, we focus on the synergistic relationship between LATE-NC and tau in AD, highlighting the aggravating role of TDP-43 aggregates on tau pathogenesis and its impact on the clinical picture and therapeutic strategies. Additionally, we discuss to what extent the molecular patterns of LATE-NC in AD differ from frontotemporal lobar degeneration with TDP-43 pathology (FTLD-TDP) neuropathological changes. Thus, we highlight the importance of tau and TDP-43 synergies for subtyping AD patients, which may respond differently to therapeutic interventions depending on the presence of comorbid LATE-NC.

The Relationship of MRI-Derived Alzheimer's and Cerebrovascular-Related Signatures With Level of and Change in Health and Financial Literacy

OBJECTIVE

The cortical thickness "signature" of Alzheimer's disease (AD-CT) and white matter hyperintensity (WMH) burden have each been associated with cognitive aging and incident AD and related dementias. Less is known about how these structural neuroimaging markers associate with other critical behaviors. We investigated associations of AD-CT and WMH volumes with a composite index of health and financial literacy given that the ability to access, understand, and utilize health and financial information significantly influences older adults' health outcomes.

DESIGN, SETTING, PARTICIPANTS

Participants were 303 adults without dementia (age∼80 years; 74% women) from the Rush Memory and Aging Project.

MEASUREMENTS

Baseline 3T MRI T1-weighted structural and T2-weighted FLAIR data were used to assess AD-CT and WMH volumes, respectively. Literacy was measured using questions designed to assess comprehension of health and financial information and concepts, yielding a total literacy score. Multivariable linear mixed effects regression models determined the relationship of each neuroimaging marker, first separately and then combined, with the level of and change in literacy.

RESULTS

Reduced AD-CT and higher WMH at baseline were each associated with lower levels of literacy; only AD-CT was associated with the rate of decline in literacy over time. The association of AD-CT with change in literacy persisted when both neuroimaging markers were included in the same model.

CONCLUSIONS

The cortical thickness signature of AD predicts changes in health and financial literacy in nondemented older adults suggesting that the multidimensional construct of health and financial literacy relies on specific brain networks implicated in AD.

Limbic-predominant age-related TDP43 encephalopathy (LATE) neuropathological change in neurodegenerative diseases

TAR DNA-binding protein 43 (TDP43) is a focus of research in late-onset dementias. TDP43 pathology in the brain was initially identified in amyotrophic lateral sclerosis and frontotemporal lobar degeneration, and later in Alzheimer disease (AD), other neurodegenerative diseases and ageing. Limbic-predominant age-related TDP43 encephalopathy (LATE), recognized as a clinical entity in 2019, is characterized by amnestic dementia resembling AD dementia and occurring most commonly in adults over 80 years of age. Neuropathological findings in LATE, referred to as LATE neuropathological change (LATE-NC), consist of neuronal and glial cytoplasmic TDP43 localized predominantly in limbic areas with or without coexisting hippocampal sclerosis and/or AD neuropathological change and without frontotemporal lobar degeneration or amyotrophic lateral sclerosis pathology. LATE-NC is frequently associated with one or more coexisting pathologies, mainly AD neuropathological change. The focus of this Review is the pathology, genetic risk factors and nature of the cognitive impairments and dementia in pure LATE-NC and in LATE-NC associated with coexisting pathologies. As the clinical and cognitive profile of LATE is currently not easily distinguishable from AD dementia, it is important to develop biomarkers to aid in the diagnosis of this condition in the clinic. The pathogenesis of LATE-NC should be a focus of future research to form the basis for the development of preventive and therapeutic strategies.

Well-Being and Aging-Related Decline in Financial and Health Literacy in Advanced Age

OBJECTIVES

Emerging evidence suggests that financial and health literacy deteriorates in advanced age. By contrast, well-being promotes health in aging. This study tested the hypothesis that well-being is associated with slower aging-related literacy decline.

METHODS

Participants were 1,099 community-based older adults without dementia at baseline. Financial and health literacy was assessed at baseline and annually thereafter via a 32-item measure. Well-being was assessed at baseline via the 18-item version of Ryff's Scales of Psychological Well-Being.

RESULTS

During up to 12 years of annual follow-up, literacy declined about 1 percentage point per year on average (β = -0.91, standard error [SE] = 0.08, p < .001); however, there was considerable variation in change in literacy between participants (random slopes variance = 1.24, SE = 0.15, p < .001). In a linear mixed-effects model adjusted for age, sex, and education, higher well-being was associated with higher starting level of literacy (β = 2.31, SE = 0.67, p = .001) and, critically, slower literacy decline (β = 0.29, SE = 0.11, p = .01). The association of higher well-being with slower literacy decline persisted in models that additionally adjusted for income, medical conditions, depressive symptoms, and a robust measure of global cognition.

DISCUSSION

This study suggests that well-being helps stave off aging-related literacy decline.

Understanding the role of financial health literacy in midlife and old age: A scoping review

As global population ageing persists, understanding older adults' capacity to navigate the financial and healthcare system is essential. This scoping review examines how the concept of financial health literacy (FHL) is described and measured in the existing literature, the factors that may affect it, and its potential outcomes in middle-aged and older adults. The review follows the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) extension guidelines to synthesise the available evidence on this topic. We utilised electronic databases and hand searching to identify relevant literature published between 2010 and 2022. A total of 29 articles were included in this review. The results showed that FHL involved accessing, understanding and utilising financial information for planning/management of healthcare expenses and selecting appropriate health services. However, FHL is not particularly depicted as a concept in the current literature, as most studies investigated health literacy, financial literacy and health insurance literacy as separate domains that were interrelated to one another. No validated measurement tool was developed for FHL. We propose five domains to indicate the concept and measurement of FHL in middle-aged/older adults: money management, management of medical bills, understanding health insurance, deciding on appropriate health services, and planning for long-term care needs. Demographic variables, such as sex (females), advanced age, cognitive impairment, low education and income and racial and ethnic minorities, were found to be related to low FHL. The reviewed studies also showed that FHL was related to several outcomes, including healthcare decision-making, physical health and psychological well-being. Hence, future studies to develop and validate assessment tools of FHL, together with the involvement of vulnerable groups, are imperative to understanding the concept of FHL. This could also facilitate the development of appropriate interventions that could enhance this capacity in the ageing population.

Assessing numerical reasoning provides insight into financial literacy

Financial literacy is linked to financial well-being and decision making. While financial literacy and numeracy skills are strongly related, the relevance of different aspects of numeracy (mental arithmetic, math achievement, and numerical reasoning) for financial literacy has not yet been examined. Data were collected from 88 cognitively healthy adults, mean age = 50 years (SD = 15); mean education = 15 years (SD = 2); 61% females; with 56% Caucasian, 36% Black, and 90% non-Hispanic. Financial literacy was measured with the widely used Big Three scale, and numeracy was measured with the Wechsler Adult Intelligence Scale-III, Arithmetic subtest; the Wide Range Achievement Test-IV, Math Computation subtest; and the Weller's Abbreviated Numeracy Scale (WANS). Regressions analyses were conducted with financial literacy as the outcome variable and each numeracy measure along with demographics (age, sex, and education) as the predictors. In all the models, only the numeracy measures were significant as individual predictors, with numerical reasoning holding the strongest association with financial literacy, followed by mental arithmetic and math achievement. The current study supports the existing literature that numeracy is important for financial literacy, and provides empirical evidence for the specific contributions of individual numeracy measures that clinicians may use to garner impressions about financial skills.

Alzheimer's Disease Neuropathological Comorbidities are Common in the Younger-Old

BACKGROUND

Clinicopathological studies have demonstrated that Alzheimer's disease dementia (ADD) is often accompanied by clinically undetectable comorbid neurodegenerative and cerebrovascular disease that alter the rate of cognitive decline. Aside from causing increased variability in clinical response, it is possible that the major ADD comorbidities may not respond to ADD-specific molecular therapeutics.

OBJECTIVE

As most reports have focused on comorbidity in the oldest-old, its extent in younger age groups that are more likely to be involved in clinical trials is largely unknown; our objective is to provide this information.

METHODS

We conducted a survey of neuropathological comorbidities in sporadic ADD using data from the US National Alzheimer's Coordinating Center. Subject data was restricted to those with dementia and meeting National Institute on Aging-Alzheimer's Association intermediate or high AD Neuropathological Change levels, excluding those with known autosomal dominant AD-related mutations.

RESULTS

Highly prevalent ADD comorbidities are not restricted to the oldest-old but are common even in early-onset ADD. The percentage of cases with ADD as the sole major neuropathological diagnosis is highest in the under-60 group, where "pure" ADD cases are still in the minority at 44%. After this AD as a sole major pathology in ADD declines to roughly 20%in the 70s and beyond. Lewy body disease is the most common comorbidity at younger ages but actually is less common at later ages, while for most others, their prevalence increases with age.

CONCLUSION

Alzheimer's disease neuropathological comorbidities are highly prevalent even in the younger-old.

Limbic-predominant Age-related TDP-43 Encephalopathy and Distinct Longitudinal Profiles of Domain-specific Literacy

PURPOSE

Emerging evidence suggests that limbic-predominant age-related TAR DNA-binding protein-43 (TDP-43) encephalopathy impacts domain-specific literacy, a complex ability not assessed in traditional cognitive evaluations. We examined longitudinal profiles of financial and health literacy in relation to limbic-predominant age-related TDP-43 encephalopathy neuropathologic change (LATE-NC).

PARTICIPANTS

A total of 275 community-dwelling older persons who had completed annual literacy assessments, died and undergone brain autopsy.

METHODS

Financial and health literacy was assessed using a 32-item instrument. Latent class mixed effects models identified groups of individuals with distinct longitudinal literacy profiles. Regression models examined group differences in 9 common age-related neuropathologies assessed via uniform structured neuropathologic evaluations.

RESULTS

Two distinct literacy profiles emerged. The first group (N=121, 44%) had higher level of literacy at baseline, slower decline and less variabilities over time. The second group (N=154, 56%) had lower level of literacy at baseline, faster decline, and greater variabilities. Individuals from the latter group were older, with fewer years of education and more female. They also had higher burdens of Alzheimer disease and LATE-NC. The group association with Alzheimer disease was attenuated and no longer significant after controlling for cognition. By contrast, the association with LATE-NC persisted.

CONCLUSION

Limbic-predominant age-related TDP-43 encephalopathy is uniquely associated with distinct longitudinal profiles of financial and health literacy in old age.

Distinct molecular patterns of TDP-43 pathology in Alzheimer's disease: relationship with clinical phenotypes

The co-existence of multiple pathologies and proteins is a common feature in the brains of cognitively impaired elderly individuals. Transactive response DNA-binding protein (TDP-43) has been discovered to accumulate in limbic brain regions of a portion of late-onset Alzheimer's disease (AD) patients, in addition to amyloid-β and τ protein. However, it is not yet known whether the TDP-43 species in the AD brain differ in their composition, when compared among different AD cases and to frontotemporal lobar degeneration cases with TDP-43 inclusions (FTLD-TDP). Furthermore, it is not known whether TDP-43 pathology in AD is related to symptoms of the frontotemporal dementia (FTD) spectrum. In this study, we investigated the molecular pattern of TDP-43 lesions with five different antibodies against different phosphorylated (pTDP-43) and non-phosphorylated TDP-43 epitopes. We analyzed a cohort of 97 autopsy cases, including brains from 20 non-demented individuals, 16 cognitively normal pathologically-defined preclinical AD (p-preAD), 51 neuropathologically-confirmed AD cases and 10 FTLD-TDP cases as positive controls. We observed distinct neuropathological patterns of TDP-43 among AD cases. In 11 neuropathologically-confirmed AD cases we found dystrophic neurites (DNs), neuronal cytoplasmic inclusions (NCIs) and/or neurofibrillary tangle (NFT)-like lesions not only positive for pTDP-43409/410, but also for pTDP-43 phosphorylated at serines 403/404 (pTDP-43403/404) and non-phosphorylated, full-length TDP-43, as seen with antibodies against C-terminal TDP-43 and N-terminal TDP-43. These cases were referred to as ADTDP + FL because full-length TDP-43 was presumably present in the aggregates. FTLD-TDP cases showed a similar molecular TDP-43 pattern. A second pattern, which was not seen in FTLD-TDP, was observed in most of p-preAD, as well as 30 neuropathologically-confirmed AD cases, which mainly exhibited NFTs and NCIs stained with antibodies against TDP-43 phosphorylated at serines 409/410 (pTDP-43409, pTDP-43409/410). Because only phosphorylated C-terminal species of TDP-43 could be detected in the lesions we designated these AD cases as ADTDP + CTF. Ten AD cases did not contain any TDP-43 pathology and were referred to as ADTDP-. The different TDP-43 patterns were associated with clinically typical AD symptoms in 80% of ADTDP + CTF cases, 63,6% of ADTDP + FL and 100% of the ADTDP- cases. On the other hand, clinical symptoms characteristic for FTD were observed in 36,4% of ADTDP + FL, in 16,6% of the ADTDP + CTF, and in none of the ADTDP- cases. Our findings provide evidence that TDP-43 aggregates occurring in AD cases vary in their composition, suggesting the distinction of different molecular patterns of TDP-43 pathology ranging from ADTDP- to ADTDP + CTF and ADTDP + FL with possible impact on their clinical picture, i.e. a higher chance for FTD-like symptoms in ADTDP + FL cases.