Journal of Alzheimer’s Disease

INTRODUCTIONBilingualism is among several lifestyle factors associated with protection against cognitive decline, yet the biological mechanisms through which it exerts these effects remain poorly understood. METHODSWe compared neuropsychological functioning and biofluid markers of brain health between active (n = 280) and passive (n = 287) Spanish-Catalan bilinguals with biomarker-confirmed Alzheimers disease (AD). RESULTSActive bilinguals outperformed passive bilinguals on tests assessing att...

BackgroundThe relationship between hip osteoarthritis (hip OA) and Alzheimers disease (AD) presents a critical paradox within the emerging "bone-brain axis": widespread phenotypic comorbidity sharply contradicts evolutionary theories of biological antagonism. This study integrates longitudinal and multi-omic analyses to determine whether this clinical overlap masks an underlying genetic neuroprotection. MethodsWe analyzed longitudinal phenotypic data from 261,767 UK Biobank participants using C...

aStructured abstractO_ST_ABSBACKGROUNDC_ST_ABSOver the past couple of decades, the role of infections, as well as the involvement of the immune system, have been highlighted in the development of dementia. METHODData from the Wisconsin Registry for Alzheimers Prevention cohort were utilized for the analysis. A history of medical conditions was searched across the cohort, and known infections and autoimmune conditions were recorded for each participant. These conditions were then compared with t...

IntroductionAlzheimers disease (AD) disproportionately affects women, with accumulating evidence suggestion a contributary role of hormones in this disparity. Given the known influence of hormones on brain health and cognition, characterizing specific profiles in dementia is crucial. In addition, sex-stratified hormonal alterations in AD and other dementias remain poorly understood. MethodsWe quantified nine steroid hormones: 11-deoxycortisol, 17-hydroxyprogesterone, aldosterone, cortisol, dihy...

BackgroundCognitively unimpaired (CU) adults vary substantially in their risk of developing mild cognitive impairment (MCI), yet most subtyping approaches focus on downstream neurobiological or cognitive markers rather than upstream, modifiable risk factors. We aimed to identify clinically meaningful subgroups of CU adults defined by integrated comorbid, behavioral, and social risk profiles, and to evaluate heterogeneity in both incident MCI risk and cardiometabolic treatment effects. MethodsWe...

IntroductionThe eligibility of anti-amyloid disease-modifying therapies (DMTs) and their integration into clinical practice in some institutions requires a specific range of Mini-Mental State Examination (MMSE) scores. Reliance on this pencil-and-paper psychometric instrument imposes operational burdens and risks perpetuating health disparities due to the tests known educational and cultural biases. This study evaluates the efficacy of the Digital Clock and Recall (DCR) - a rapid, FDA-listed dig...

Background and ObjectivesProgression from mild cognitive impairment (MCI) to Alzheimers Disease and Related Dementias (AD/ADRD) varies widely across individuals, yet the mechanisms underlying this heterogeneity remain unclear. Identifying clinical and social determinants influencing this transition could enable earlier intervention. While cardiovascular and social risk factors are established contributors to dementia incidence, their role in progression from MCI to dementia may differ. Few studi...

IntroductionThis clinical trial investigates the efficacy and safety of a personalized 15-day accelerated intermittent theta-burst stimulation (aiTBS) protocol, targeted at either the default mode network (DMN) or the fronto-parietal network (FPN), in individuals with mild Alzheimers disease (AD). Methods45 patients with mild AD were randomized 1:1:1 to receive 15 consecutive days of high-dose aiTBS (7200 pulses/day) targeting the DMN or FPN, or sham. The primary outcome was the change in ADAS-...

INTRODUCTIONAlzheimers disease (AD) diagnostic guidelines emphasize subjective cognitive decline (SCD) preceding mild cognitive impairment (MCI), implicitly assuming awareness of cognitive decline (ACD) is preserved in preclinical AD. This study aimed to evaluate associations of decreased ACD with multimodal core AD biomarkers in cognitively unimpaired (CU) individuals. METHODSWe analyzed data from CU individuals with baseline CSF biomarkers and 3-year longitudinal neuropsychological assessment...

Background: Quantitative genome wide association studies (GWAS) primarily rely on additive linear models that compare average phenotypic differences between genotype groups. While effective for detecting common variants of moderate effect in large sample sizes, such approaches inherently reduce high resolution phenotypic data to summary statistics (group averages), potentially limiting the detection of subtle genotype phenotype relationships. Genomic Informational Field Theory (GIFT) is a recent...

BackgroundCommunity-based clinical-pathologic studies have been instrumental to examine the association of Alzheimers disease and related disorders (AD/ADRD) with age and dementia in very-old non-Latino Whites. Here, we show the age distribution of four AD and three additional common neuropathologies across the adult lifespan and examine their relation to dementia and cognitive impairment in old and young Brazilian adults. MethodsWe examined 5,376 brains from decedents age 18 years or older (52...

Background and ObjectivesAlzheimers disease (AD) is characterized by early disruptions in brain connectivity. However, how genetic and biological markers of AD risk relate to dynamic functional connectivity (dFC) remains unclear. This study examined whether AD-related pathology, genetic risk, and blood-based biomarkers (BBMs) of neurodegeneration are associated with local and distant resting-state dFC patterns, and whether these relate to cognitive performance in cognitively normal older adults....

Subtle alterations in awareness may emerge in the preclinical stage of Alzheimers disease (AD), yet their clinical significance and translational relevance remain unclear. This study aimed to evaluate associations of distinct awareness trajectories with clinical and multimodal AD biomarker measurements in cognitively unimpaired (CU) older adults. This prospective study analyzed data from the Anti-Amyloid Treatment in Asymptomatic Alzheimers (A4) and Longitudinal Evaluation of Amyloid Risk and N...

Structured AbstractO_ST_ABSBACKGROUNDC_ST_ABSPatient reports are the standard when examining subjective cognitive decline (SCD). Recent research suggests that informant and clinician reports may also be associated with cognition. This study examined differences between patient, informant, and clinician definitions of SCD and their relationship to cognition. METHODSData from 4290 older adults (n=1690 normal controls, NC; n=840 mild cognitive impairment, MCI; n=1760 Alzheimers disease, AD) were e...

BackgroundAPOE-{rho}.4 is the strongest genetic risk factor for Alzheimers disease (AD), and plasma phosphorylated tau217 (P-tau217) is a highly sensitive and specific biomarker for AD pathology. Their combined utility to predict cognitive decline before onset of AD has not been systematically evaluated. MethodsUsing longitudinal data from multiple cohorts, we evaluated plasma P-tau217 as a predictor of when cognitive impairment occurs in AD. P-tau217 concentrations were analyzed as continuous ...

BackgroundGabapentin prescriptions have increased 123% since 2010, reaching 15.5 million Americans annually. Recent studies suggest gabapentin-dementia associations, but whether concomitant medications modify this risk is unknown. Both gabapentin and calcium channel blockers (CCBs) affect neuronal calcium signaling through distinct mechanisms, raising the possibility of pharmacodynamic interaction. MethodsActive comparator new-user cohort study using Rutgers Clinical Research Data Warehouse (20...

IntroductionPhosphorylated tau-217 (p-tau 217) is widely used as a plasma-based biomarker for Alzheimers Disease (AD) detection, demonstrating superior accuracy for detecting brain amyloid pathology. However, 30-50% of patients fall within an intermediate diagnostic "gray zone" where biomarker results are indeterminate, often decreasing physician confidence and requiring subsequent diagnostic workup. To address this, we developed a two-stage machine learning algorithm GRAD: Gatekeeper & Reflex ...

INTRODUCTIONThe pathophysiology and risk factors for Alzheimers disease (AD) and dementia are insufficiently known. We studied the connections between gut microbiome, overall dementia and AD in a prospective, population-based cohort. METHODSWe followed a population based random sample of 4,055 individuals (FINRISK 2022) for 16 years, with 330 cases of incident dementia and 280 AD cases. Gut microbiome community diversity and composition were assessed against future dementia and AD risk. Competi...

BackgroundAlzheimers disease (AD) is a neurodegenerative disorder marked by cognitive decline, memory impairment, and functional deterioration. Its complex pathogenesis involves factors such as amyloid plaques, tau tangles, neuroinflammation, and synaptic dysfunction, but the precise mechanisms remain unclear, hindering effective treatment. Genetic, environmental, and lifestyle factors contribute to AD risk, yet their interactions are poorly understood. Recent advances in transcriptomics and met...

Individuals who carry two copies of the apolipoprotein E {varepsilon}4 (APOE{varepsilon}4) allele are at high risk of developing Alzheimers disease (AD), yet the effects of APOE {varepsilon}4 homozygosity on biological pathways related to AD over the lifespan are unknown. Here we analyzed the plasma proteomes of APOE {varepsilon}4/{varepsilon}4 individuals with and without AD-related cognitive impairment (n=413) and compared them to the proteomes of cognitively unimpaired individuals with APOE {...