Journal of Alzheimer's Disease

BackgroundCardiovascular health factors are associated with cognitive decline and risk of dementia, including Alzheimer disease (AD); however, this has been mostly studied in late life. We investigated whether vascular and lifestyle factors are associated with AD plasma and imaging biomarkers in midlife. MethodsWe investigated 1,406 participants from the Coronary Artery Risk Development in Young Adults (CARDIA) study with information on vascular and lifestyle factors framed from the American Heart Association (AHA) "lifes essential 8" (LE8) guidelines for cardiovascular health at early midlife (mean age 45.0 {+/-} SD 3.6) and AD biomarkers in late midlife (mean age 60 {+/-} SD 3.5). LE8 was calculated and categorized into poor (0-49), intermediate (50-79), and ideal (80-100) cardiovascular health, based on 8 components including smoking, diet, body mass index (BMI), sleep, fasting glucose, blood pressure, cholesterol, and physical activity. We assessed the AD plasma biomarkers phosphorylated tau 217 (ptau-217) and amyloid beta 42/40 ratio (A{beta}42/40) and the Spatial Pattern of Abnormality for Recognition of Early AD (SPARE-AD), an algorithm that characterizes AD-like brain atrophy on brain MRI. We used linear regression to examine the association between LE8 and log transformed and standardized AD biomarker measures adjusting for age, sex, race, education, and kidney function. ResultsCompared to ideal LE8, intermediate (67.9% of participants) and poor (12.6%) LE8 was associated with lower A{beta}42/40 (adjusted mean difference: -2.37, 95% CI: -2.38 to -2.36 and -2.38, 95% CI: -2.40 to -2.36, respectively). There was no association between the LE8 group and ptau-217 level. Moreover, compared to ideal LE8 participants, those with poor LE8 had higher SPARE-AD atrophy pattern (adjusted mean difference: -0.71, 95% CI: -0.81 to -0.62). ConclusionThese findings indicate that poor cardiovascular health in midlife, as defined by the AHA LE8, is linked to less favorable early AD biomarker profiles, particularly reflecting greater amyloid burden and structural brain changes.

BackgroundSocial determinants of health (SDOH) are increasingly recognized as contributors to Alzheimer disease (AD) risk, yet the impact of multidimensional social disadvantage early AD-related pathophysiology remains poorly understood. MethodsWe studied 1,466 participants from the Coronary Artery Risk Development in Young Adults (CARDIA) cohort with SDOH assessed in early midlife (mean age 40 {+/-} 3.6 years) and plasma AD biomarkers measured 20 years later. A comprehensive SDOH index was constructed from 12 indicators spanning five domains (economic stability, education, neighborhood and physical environment, community and social context, and health care access). We examined associations between SDOH quartile and log-transformed, standardized plasma phosphorylated tau 217 (p-tau217), neurofilament light chain (NfL), and amyloid-{beta}42/40 (A{beta}42/40) using linear regression adjusted for age, sex, race, and estimated glomerular filtration rate. Linear trends across SDOH quartile were also evaluated. ResultsParticipants in the most disadvantaged SDOH quartile had higher p-tau217, higher NfL and lower A{beta}42/40 level compared with those in the least disadvantaged quartile (p-tau 217: {beta} = 0.12, 95% CI 0.03-0.21, p = 0.008; NfL: {beta} = 0.20, 95% CI 0.05-0.35, p = 0.009; A{beta}42/40: {beta} = -0.15, 95% CI -0.30-0.00, p=0.05). There was also a significant trend across quartile (p-tau 217: p for trend = 0.012; NfL: p for trend =0.001). Analyses of individual SDOH domains indicated that lower economic stability, poorer health care access, and lower education were associated with higher NfL, and poorer health care access was associated with higher p-tau217. ConclusionsGreater SDOH disadvantage in early midlife was associated with higher levels of plasma AD biomarkers reflecting AD pathology and neurodegeneration decades later. These findings suggest that social disadvantage during midlife may contribute to early AD-related biological changes and highlight potentially modifiable social factors relevant for dementia prevention.

BackgroundFor early detection of Alzheimers disease, it is essential to identify individuals showing cognitive performance consistent with the mild cognitive impairment (MCI) range during preliminary screening, ideally using methods that extend beyond conventional cognitive assessments. Non-invasive, easily accessible screening tools applicable in daily life are increasingly needed. Facial expressions, particularly during rest, may offer promising biomarkers for MCI level detection. This study aimed to identify specific facial features associated with MCI level during rest to inform development of facial expression-based screening tools. MethodsParticipants were classified into an MCI level group and a healthy control (HC) group based on the Montreal Cognitive Assessment (MoCA) scores. Facial Action Units (AUs) were extracted from video recordings of resting-state facial expressions in 31 individuals with MCI level and 14 HC. Two statistical models were employed: a multilevel zero-inflated beta regression model for intensity of 17 AUs and a multilevel logistic regression model for presence or absence of 18 AUs. ResultsIn the zero-inflated beta regression, the AU relates to upper lip raiser showed a significant group effect (MCI level vs. HC; p <0.001), remaining significant after multiple comparison correction. The logistic regression revealed significant group differences for the AUs related to lip tightener (p <0.001) and lip suck (p <0.001), both remained significant after multiple comparison correction. ConclusionsDistinctive facial action patterns during rest were observed in individuals with MCI level. These findings highlight the potential of resting-state facial expressions as a basis for novel, unobtrusive screening tools for early MCI level detection.

BACKGROUND: Neuropsychiatric symptoms (NPS) are prevalent and debilitating in Alzheimer's disease (AD). Existing pharmacologic treatments are often ineffective and associated with serious adverse events. Identifying modifiable risk factors (MRFs) is critical for prevention and treatment. METHODS: Capitalizing on data from 14,497 individuals with AD from the National Alzheimer's Coordinating Center (NACC) database, we examined longitudinal associations between modifiable risk factors, APOE genotype and NPI-Q-assessed NPS using Cox proportional hazards models adjusted for demographics. RESULTS: Diabetes, alcohol consumption, smoking, and TBI were associated with an increased risk of specific NPS in AD. APOE{varepsilon}4 carrier status was linked to multiple NPS, showing a dose-response relationship. Education, LDL-C, and corrective lenses were protective; hypertension showed no associations. CONCLUSION: These findings strongly suggest that individual MRFs are associated with specific NPS in line with a complex etiology underlying these symptoms. Early detection and management of vascular, lifestyle and sensory factors could reduce NPS.

INTRODUCTION: Bilingualism is a proposed cognitive reserve factor that delays symptom onset in Alzheimer's disease (AD), though current evidence lacks biomarker confirmation. This retrospective study examined bilingualism's association with symptom onset across AD clinical stages, including biomarker-confirmed cases. METHODS: Participants from the Sant Pau Memory Unit spanning amnestic mild cognitive impairment (MCI), amnestic dementia, and biomarker-confirmed AD were analyzed, with balanced representation of active and passive Spanish-Catalan bilinguals. Linear regression models evaluated associations between bilingualism and reported age at symptom onset, controlling for education, sex, and disease severity. RESULTS: Active bilingualism was associated with delayed symptom onset in amnestic MCI (2.21 years), amnestic dementia (1.42 years), and biomarker-confirmed AD (1.45 years; ps < .05). Higher education was associated with earlier onset, likely representing healthcare seeking behavior. DISCUSSION: Bilingualism protects against earlier symptom manifestation in MCI and AD, supporting bilingualism as a contributor to cognitive reserve.

Objectives. Despite the body of literature on genetic risk factors for dementia, little is known on protective genetic factors associated with favourable cognitive ageing in the oldest population. In Europe, Italy has a leading position with a swelling population of centenarians, and the urban area of Genoa in the Liguria region has one of the highest prevalence of centenarians. The COOL study is a not-for-profit, multicentric study involving a cohort of centenarians (aged >99) living in the Genoa area. The ultimate aim is the identification of genomic biomarkers associated with cognition in the oldest old population. Results. Participants underwent a semi-structured interview on personal, disease and family history, and a neuropsychological assessment of the main cognitive domains. As of July 2025, we enrolled 88 centenarians (age range: 99-108, median 100.56) with and without cognitive impairment; 32 subjects were followed up. All participants were of Italian ancestry, 81% were female. The cognitive profile in assessed subjects showed a wide range of cognitive health measures (CDR 0-5; MMSE 3-30, median 24). Whole peripheral blood and DNA samples from 67 participants were stored. Conclusions. We demonstrated that the protocol is feasible, and acceptable by participants and their families. A comprehensive phenotype dataset was established, and DNA samples were stored. Centenarians exhibited a broad spectrum of cognitive profiles, from preserved cognition to severe dementia. These findings will eventually allow to interpret the profiles of genomic variants as associated with variability of cognitive performance in centenarians. The molecular underpinnings of healthy cognitive ageing could inform health policy strategies in the general population.

INTRODUCTION: Postmenopausal estrogen decline may contribute to Alzheimer's disease (AD) risk, but longitudinal evidence linking circulating estrogens to cerebrospinal fluid (CSF) biomarkers is lacking. METHODS: We analyzed 866 female participants from the European Prevention of AD Longitudinal Cohort Study with baseline serum estradiol and estrone measured by liquid chromatography tandem mass spectrometry and repeated CSF measurements of amyloid-beta (A{beta})42, phosphorylated (p) Tau181, and total (t) Tau. RESULTS: Neither estradiol nor estrone was associated with longitudinal A{beta}42. Higher estradiol was associated with lower baseline tau and slower tau increases over time. Baseline estradiol-tau associations were stronger in apolipoprotein E (APOE) {epsilon}4 carriers, though APOE{epsilon}4 did not modify longitudinal associations. Amyloid positivity did not moderate hormone-tau associations but was associated with steeper tau increases over time. Estrone showed no significant associations. DISCUSSION: These findings suggest a more consistent relationship between estradiol and tau-related rather than amyloid-related pathology.

Background: The Dementia Supporter Initiative is a national public education program in Japan that aims to foster positive attitudes and appropriate understanding of dementia to support people with Alzheimer's disease and related dementia in the community. However, its influence on the community as a whole remains unclear. Objective: This study examined the relationship between dementia supporter training and residents' attitudes and recognition related to dementia at the municipal level. Methods: This ecological cross-sectional study linked municipal-level data from the Japan Gerontological Evaluation Study 2022 wave with publicly available information on the number of dementia supporters. Residents' beliefs and attitudes toward dementia and recognition of dementia consultation services were assessed by mail questionnaires and aggregated at municipal level. The proportion of dementia supporters in each municipality was calculated as of September 2022. Results: Data from 69 municipalities were analyzed. The mean proportion of dementia supporters was 13.47% (2.62-44.85). A higher proportion of dementia supporters was positively correlated with community support-seeking for a family member with dementia (r = 0.328) and recognition of dementia consultation services (r = 0.501). Regression analysis adjusted for municipal covariates also showed their positive associations (per 10-percentage-point increase: coef. = 1.44, p = 0.047; coef. = 3.12, p < 0.001, respectively). No associations were observed with residents' positive attitudes and appropriate understandings of dementia. Conclusions: Wider dissemination of dementia supporters may contribute to better recognition of community support resources, but may be insufficient to influence broader public attitudes and understanding of dementia at the community level.

Neurodegenerative and neuropsychiatric disorders are leading causes of disease burden in middle-aged and older adults. We aimed to quantified and estimated the temporal and spatial characteristics of individual and concurrent burden of dementia with eight mental disorders worldwide. Our findings revealed that although a trend of decreased prevalence and incidence of dementia was observed in most regions over the past 31 years, dementia demonstrated greater comorbidity burden of neurodevelopmental disorders (especially attention-deficit/hyperactivity disorder and idiopathic developmental intellectual disability) in Middle East and North Africa. In high-SDI areas such as Western Europe, and high-income north America countries, it was more linked to mental disorders including anxiety disorders, eating disorders, and schizophrenia. In addition, neurodevelopmental disorders have been highly comorbid with both early- and late-onset of dementia. Our findings underscore the urgent need for proactive, integrated, and life-course health management strategies to achieve precision prevention and control of dementia, mental disorders and their comorbidities.

INTRODUCTION: Overcoming dementia-related stigma is a global challenge, but tools to assess stigma among family caregivers of people living with dementia remain limited. This study examined the validity and reliability of the Japanese version of the Family Stigma Instrument for family caregivers of people living with dementia (J-FAMSI-dementia), originally developed in the United Kingdom. METHODS: A total of 372 informal caregivers aged 18 to 79 years of family members living with dementia completed an internet survey. The J-FAMSI-dementia comprises five subscales (stigma by association; perceived, affective, and behavioral affiliate stigma; and positive aspects of caregiving), developed through forward and back translations. RESULTS: Confirmatory factor analysis supported an acceptable five-factor model. All subscales showed high internal consistency and moderate to good test-retest reliability. Correlations with dementia attitude, caregiving burden, and depressive symptoms supported construct validity. DISCUSSION: The J-FAMSI-dementia demonstrated acceptable validity and reliability and may help identify dementia-related stigma among family caregivers.

Background and ObjectivesMultifactorial interventions have been reported to be effective in improving cognitive function; however, their long-term effectiveness in community settings remains to be sufficiently examined. This study aimed to investigate the effects of a socially implemented multifactorial intervention program on dementia onset, long-term care insurance certification, and post-intervention cognitive and physical functions. MethodsThis retrospective observational study collected data from three municipalities. The study population comprised individuals suspected of having mild cognitive decline based on cognitive function screening tests conducted by March 31, 2024, and who had been invited to participate in a dementia prevention class, but had not applied for long-term care insurance at the time of the invitation. Participants were classified into class participation and non-participation groups for analysis. Most participants attended the class only once (intervention duration: 4 or 6 months). ResultsData from 104, 218, and 256 individuals were collected from the three municipalities, respectively. No significant association was found between class participation and suppression of dementia onset or long-term care insurance certification in any of the municipalities. Regarding pre-post comparisons among class participants, significant improvements in cognitive function and some physical functions were observed in all the three municipalities. ConclusionsThe multifactorial interventions implemented in community settings showed no effect on dementia onset or health outcomes. However, class participation was associated with improvements in cognitive function and some physical functions. These findings suggest that implementing programs based on evidence can achieve effects similar to those observed in studies conducted under ideal conditions.

Background: Estimates from high income countries suggest that approximately 40% of dementia cases may be attributable to modifiable risk factors across the life course. However, most evidence informing these estimates originates from high income settings, and population level estimates from sub Saharan Africa remain limited. We aimed to estimate population attributable fractions (PAFs) for modifiable dementia risk factors in the Democratic Republic of the Congo (DRC). Methods: We conducted a cross sectional analysis of community dwelling adults aged 65 years and older enrolled in the Etude du Vieillissement Cognitif et de Demence en Republique Democratique du Congo (EVCD RDC). Prevalence estimates of dementia and associated exposures were derived from prior epidemiological studies in this population. Odds ratios were estimated using logistic regression, and population attributable fractions were calculated by integrating exposure prevalence with effect size estimates. To account for correlations between exposures, communality weights were applied when estimating combined PAFs across risk factors. Findings: Combined modifiable risk factors were estimated to account for 37.3% (95% CI 14.3 to 55.6) of dementia cases in this sample. Poverty had the largest weighted PAF (18.4%, 95% CI 13.3 to 22.8), followed by low educational attainment (11.3%, 95% CI 7.3 to 15.3) and depression (5.8%, 95% CI 2.8 to 8.6). Additional contributors included traumatic events (5.4%), war exposure (2.1%), diabetes (1.3%), and hypertension (1.1%). A hypothetical 15% proportional reduction in these risk factors was estimated to reduce dementia prevalence by 6.4% (95% CI 2.1 to 10.8), corresponding to approximately 10 700 cases prevented in the DRC by 2025. Interpretation: Modifiable risk factors account for a substantial proportion of dementia burden in the DRC, with structural determinants such as poverty and education contributing the largest fractions. Dementia prevention strategies in low and middle income countries may therefore require broader public health approaches that address socioeconomic and structural determinants alongside conventional clinical risk factors.

INTRODUCTION: Bilingualism may confer resilience via enhanced neural integrity. However, evidence for bilingualism's neuroprotective effect is mixed, and studies across Alzheimer's disease (AD) variants are scarce. This study examined gray matter volume (GMV) differences between bilinguals and monolinguals with amnestic AD and logopenic variant primary progressive aphasia (lvPPA). METHODS: In 136 amnestic AD and 88 lvPPA participants with neuropsychological assessments and structural MRI, we analyzed differences between monolinguals and bilinguals within each variant, controlling for demographic covariates. RESULTS: Amnestic AD bilinguals exhibited less GMV in hippocampal, fusiform, and occipital regions compared to monolinguals. LvPPA bilinguals had less temporal and occipital volumes, but they had greater volumes in inferior parietal regions, which are considered a disease epicenter in lvPPA. Cognitive performance in monolinguals and bilinguals was comparable within variants. DISCUSSION: Bilingualism may support cognitive reserve (preserved cognition despite reduced GMV) in both AD variants, with additional brain reserve in lvPPA.

Background The majority of family dementia caregivers in the United States (U.S.) are now young and middleaged adults. However, little research has been conducted to understand how caregiver needs and preferences for support differ depending on their phase of adulthood. This study evaluated differences in mental health, caregiving readiness, desired supports, and intervention preferences among early (<46 years), middle (46 to 60 years), and late (>60 years) adulthood dementia caregivers. Methods A cross sectional survey was conducted with 202 family dementia caregivers aged 22 to 88. Caregivers completed validated measures of burden, anxiety, depression, well being, time pressure, dementia knowledge, caregiving preparedness, and positive aspects of caregiving. Desired supports and preferences for intervention format, program type, and frequency were assessed. Analyses examined both categorical adulthood phase and continuous age associations with caregiver outcomes, with alpha thresholds of p<.05. Results Early adulthood caregivers self reported higher anxiety symptoms (relative to late adulthood caregivers) and perceived time pressure (relative to middle and late adulthood caregivers). Relative to late adulthood caregivers only, early adulthood caregivers more frequently endorsed desired support for supplemental care and safety tools for the person with dementia, as well as willingness to engage in individual counseling and automated, digital supports. Relative to both middle adulthood and late adulthood caregivers, they also more frequently expressed desired support for their own mental health. Conclusions Dementia caregiving in early adulthood is associated with distinct psychological and practical support needs, suggesting life course informed interventions may enhance relevance and engagement.

Introduction. There is consistent evidence of a disadvantage in bilinguals' speech production compared to monolinguals in healthy individuals, but studies investigating this phenomenon in clinical populations such as Mild Cognitive Impairment (MCI) and Alzheimer's Disease (AD) are scarce. Given that both clinical groups are characterized by wordfinding difficulties, understanding how bilingualism influences speech production in these populations is essential. Methods. Early and highly proficient Catalan-Spanish bilinguals (active bilinguals) were compared to Spanish-dominant speakers with low proficiency in Catalan (passive bilinguals) using a picture-naming task. The study included 58 older adults, 66 patients with AD, and 124 individuals with MCI. Reaction times, accuracy, and error types were collected in the naming task in each individual's dominant language. Results. First, active bilinguals demonstrated faster naming latencies than passive bilinguals, particularly for low-frequency words. Second, active bilinguals with MCI exhibited more naming errors than passive bilinguals with MCI, including a higher incidence of crosslanguage intrusions and anomia. Third, passive bilinguals with MCI and AD showed more semantic errors than active bilinguals. Discussion. These findings underscore the impact of second language use on naming performance in MCI and AD. Moreover, they provide insight into the potential mechanisms underlying lexical retrieval differences in bilinguals, including lexico-semantic processing and language control.

Summary Background Although CAIDE (Cardiovascular Risk Factors, Aging, and Dementia) score estimates 20 year dementia risk, prior studies have largely focused on global or composite measures. Only a few studies investigated on cognitive functions and structural neuroimaging markers, and the available structural neuroimaging evidence has largely been derived from subsamples or highly selected small cohorts rather than full population based cohorts. We therefore not only investigated associations between CAIDE score and cognitive performance but also explored structural neuroimaging markers in middle to older aged population. Methods Of 2,864 participants who were available for structural magnetic resonance imaging (MRI) data at baseline, we excluded 230 participants who have neurological and cardiovascular disease at baseline. We also further excluded 209 participants without having exposure, covariates, and cognitive assessments data, including 2,425 participants for the final analysis. The main exposure is CAIDE score (0 to 15) were calculated from age, sex, education, systolic blood pressure, body mass index, total cholesterol, and physical activity and categorized as low risk (<6), moderate risk (6 to 7), and high risk (7<) at baseline. The main outcomes were neuropsychological assessment battery included Story recall, Visual reproductions, Verbal fluency, Trail making, Digit symbol coding, and Stroop tests. Findings Of 2,425 healthy participants (mean age of 58.5 [6.5]; men 1,189 [49.0]), higher CAIDE risk groups were associated with poorer cognitive performance. Compared with low risk group, the high risk group showed significantly lower performance across all 12 cognitive assessments (all p <.001). The moderate risk group also showed lower performance in visual reproduction (immediate and delayed recall), digit symbol oding, and Stroop (word and color) reading tests. Interpretation This large based population study showed the highest risk group were independently associated with lower cognitive performance across all domains compare to the lowest risk group, suggesting the potential importance of managing these features for preserving neurological health in middle and older aged adults.

Background: Anomia is common in frontotemporal dementia (FTD), although its clinical prominence varies by subtype, with the most marked impairment typically observed in primary progressive aphasia (PPA). It remains unclear whether naming impairment reflects language-specific impairment or broader cognitive severity, and how it relates to other cognitive domains across FTD syndromes. Methods: Fifteen healthy controls and twenty-two individuals across the FTD spectrum, including variant-specified and unclassifiable (NOS) presentations, completed two confrontation naming tasks (Boston Naming Test and Multilingual Naming Test) and a global cognitive screening measure (Montreal Cognitive Assessment, MoCA). Patient participants additionally completed a standardized language battery (Western Aphasia Battery Revised) and a comprehensive neuropsychological assessment (Uniform Data Set). Naming performance was compared between groups and associations with language severity, global cognition, and domain-specific cognitive functions were examined using regression analyses. Results: Naming was impaired in patients relative to healthy controls but did not differ between patient groups. Naming was strongly associated with language severity, but not global cognition. A significant group-by-MoCA interaction indicated that MoCA was positively associated with naming only in the unclassifiable group. In addition, naming was associated with episodic memory across both verbal and non-verbal domains. Conclusions: Naming in FTD primarily reflects language severity rather than global cognitive impairment. A robust association between naming and episodic memory suggests potential contributions from semantic cognition, shared frontally mediated retrieval processes, or parallel cognitive decline. These findings support the use of naming as a marker of language dysfunction while highlighting its relevance to broader cognitive systems in FTD.

PURPOSE: Alzheimer disease (AD) is associated with cognitive impairment, brain atrophy, and elevated amyloid-beta and tau. The study aimed to characterize regional atrophy associated with elevated amyloid-beta and tau, as measured by [18F]florbetapir (FBP) and [18F]flortaucipir (FTP) positron emission tomography (PET), respectively, and determine whether combining PET and atrophy data improves the prediction of cognitive impairment. METHODS: Alzheimer Disease Neuroimaging Initiative data (n = 381) were retrospectively analyzed. PET results were correlated with cortical thickness, gray matter (GM) volumes, Mini-Mental State Examination, and Montreal Cognitive Assessment. Linear/logistic regression and area under the curve (AUC) were used to evaluate for significant correlations and compare performances in distinguishing cognitive impairment, respectively. RESULTS: Incremental loss of cortical thickness and GM volume was observed from FBP-/FTP- (n = 205) to single PET-positive (FBP+/FTP-, n = 133; FBP-/FTP+, n = 5) and FBP+/FTP+ (n = 38) groups, particularly in the temporal and parietal lobes. FBP+/FTP+ showed the most severe cortical thickness loss in the entorhinal cortex, temporal lobe GM atrophy, and cognitive impairment. Adding brain atrophy as the third variable resulted in higher odds ratios and improved AUCs for cognitive impairment, with FBP+/FTP+/temporal GM or entorhinal cortical atrophy+ demonstrating the strongest associations with cognitive impairment. CONCLUSION: A multimodal approach combining PET and MRI may help improve the assessment of cognitive impairment in AD.

BackgroundThe AT(N) biological framework classifies Alzheimers disease (AD) pathology using CSF biomarkers, with the A+T+ profile defining biological AD and the A-T+ profile representing a biologically distinct entity consistent with suspected non-Alzheimers pathophysiology, such as primary age-related tauopathy. Functional assessment capable of differentiating these profiles non-invasively remains limited. This study investigates whether cognitive vergence and pupillary temporal dynamics during a visual oddball task can distinguish A-T+ from A+T+ biological profiles in individuals with mild cognitive impairment (MCI). MethodsThirty-eight participants with MCI (12 A-T+, 26 A+T+) classified by CSF biomarkers completed a visual oddball task (80% distractors, 20% targets) under continuous eye-tracking. Linear mixed-effects models examined profile x condition interactions on full time series and six trial-level temporal features. Participant-level differentiation was assessed using binomial logistic regression, adjusting for age, sex, and MMSE. ResultsBoth profiles showed comparable overall oculomotor response magnitudes but diverged markedly in temporal organization. Significant profile x condition interactions emerged for cognitive vergence global slope, time to peak, and pupillary time to peak. Logistic regression confirmed that timing features discriminated biological profiles at the participant level, with differentiation reversing direction between distractor and target conditions. A-T+ participants also maintained superior target detection accuracy (89.3% vs. 82.4%, p = 0.001). ConclusionCognitive Vergence and pupillary temporal dynamics during an oddball task provide condition-dependent functional oculomotor signatures that systematically differentiate AT(N) biological profiles in MCI, suggesting that oculomotor assessment may offer an accessible, non-invasive complement to CSF-based profile characterization.

Digital health technologies (DHT) offer a promising solution to the timely identification of early Alzheimer's disease (eAD) to enable early treatment. This study evaluated the feasibility, acceptability, adherence, reliability, and preliminary clinical and content validity of the novel AD Digital Assessment Suite (AD-DAS). 123 individuals (32 healthy controls (HC), 31 amyloid-PET negative (SCDn), 30 amyloid-PET positive (SCDp) with subjective cognitive decline, and 30 early AD (eAD)) participated. AD-DAS was remotely deployed for 28 days. Remote testing was feasible (97.6% completers), acceptable (>85% ''good''), and associated with high adherence (96%). Metrics showed moderate to excellent test-retest reliability (ICC 0.53-0.91), associations with clinical comparators (adjusted R2 0.01-0.24), differentiated eAD from other known groups (absolute log odds differences 0.6-3.28), and correlated with brain atrophy in expected regions. Episodic and working memory AD-DAS metrics differentiated SCDp from SCDn participants. These preliminary findings suggest that AD-DAS may be a promising tool for detecting cognitive impairments in early AD stages.