Global, regional, and national burden of Alzheimer's disease and other dementias, 1990-2016: a systematic analysis for the Global Burden of Disease Study 2016

The Protective Effect of Vitamin D on Dementia Risk in Hemodialysis Patients

BACKGROUND

Patients with end-stage renal disease (ESRD) undergoing hemodialysis are at an elevated risk of developing dementia, potentially linked to the high prevalence of vitamin D deficiency in this population, which may contribute to cognitive impairment. Nevertheless, the impact of vitamin D supplementation on the risk of dementia in hemodialysis patients remains uncertain, necessitating further investigation to elucidate the potential benefits of vitamin D intervention in this vulnerable group.

METHODS

In this propensity-score-matched comparative cohort study, we sought to assess the impact of vitamin D supplementation on the occurrence of dementia in patients with end-stage renal disease (ESRD) undergoing hemodialysis. A total of 1424 patients were included and matched 1:1 using propensity scores. The study population was divided into two groups: those receiving vitamin D supplementation at a dose of ≥70 μg/week and those without any supplementation. The primary outcome of interest was the incidence of dementia. We calculated adjusted hazard ratios (aHRs) to examine the association between vitamin D supplementation and the risk of dementia while controlling for relevant covariates.

RESULTS

The adjusted hazard ratio (aHR) comparing vitamin D supplementation to no supplementation was 0.44 (95% CI 0.29-0.69; p < 0.0001), demonstrating a significant decrease in the risk of dementia associated with vitamin D supplementation. The aHRs for vitamin D supplementation at different dose ranges (70-105, 106-350, 351-1000, and >1000 μg/week) were 0.51, 0.49, 0.43, and 0.41, respectively (p for trend < 0.0001). These findings suggest a potential dose-dependent relationship between vitamin D supplementation and the reduction of dementia risk.

CONCLUSIONS

In our study, we found that vitamin D supplementation at doses of ≥70 μg/week significantly reduced the risk of dementia in patients with end-stage renal disease (ESRD) undergoing hemodialysis. Furthermore, our results indicated a dose-dependent effect, with higher doses of supplementation correlating with a greater reduction in dementia risk. These findings underscore the potential of vitamin D supplementation as a preventive approach for cognitive impairment in this high-risk population.

Uncovering Diverse Mechanistic Spreading Pathways in Disease Progression of Alzheimer's Disease

Background

The AT[N] research framework focuses on three major biomarkers in Alzheimer's disease (AD): amyloid-β deposition (A), pathologic tau (T), and neurodegeneration [N].

Objective

We hypothesize that the diverse mechanisms such as A⟶T and A⟶[N] pathways from one brain region to others, may underlie the wide variation in clinical symptoms. We aim to uncover the causal-like effect of regional AT[N] biomarkers on cognitive decline as well as the interaction with non-modifiable risk factors such as age and APOE4.

Methods

We apply multi-variate statistical inference to uncover all possible mechanistic spreading pathways through which the aggregation of an upstream biomarker (e.g., increased amyloid level) in a particular brain region indirectly impacts cognitive decline, via the cascade build-up of a downstream biomarker (e.g., reduced metabolism level) in another brain region. Furthermore, we investigate the survival time for each identified region-to-region pathological pathway toward the AD onset.

Results

We have identified a collection of critical brain regions on which the amyloid burdens exert an indirect effect on the decline in memory and executive function (EF) domain, being mediated by the reduction of metabolism level at other brain regions. APOE4 status has been found not only involved in many A⟶N mechanistic pathways but also significantly contributes to the risk of developing AD.

Conclusion

Our major findings include 1) the region-to-region A⟶N⟶MEM and A⟶N⟶MEM pathways exhibit distinct spatial patterns; 2) APOE4 is significantly associated with both direct and indirect effects on the cognitive decline while sex difference has not been identified in the mediation analysis.

Prevalence of treated patients with Alzheimer's disease: current trends and COVID-19 impact

BACKGROUND

There are few updated studies on the prevalence and management of Alzheimer's disease (AD), which could be underdiagnosed or undertreated. The COVID-19 pandemic may have worsened the deficiencies in the diagnosis and treatment of these patients. Electronic medical records (EMR) offer an opportunity to assess the impact and management of medical processes and contingencies in the population.

OBJECTIVE

To estimate AD prevalence in Spain over a 6-year period, based on treated patients, according to usual clinical practice. Additionally, to describe the management of AD-treated patients and the evolution of that treatment during the 2020 COVID-19 pandemic.

METHODS

Retrospective study using the Spanish IQVIA EMR database. Patients treated with donepezil, galantamine, rivastigmine, and/or memantine were included in the study. Annual AD prevalence (2015-2020) was estimated and extrapolated to the national population level. Most frequent treatments and involved specialties were described. To assess the effect of COVID-19, the incidence of new AD cases in 2020 was calculated and compared with newly diagnosed cases in 2019.

RESULTS

Crude AD prevalence (2015-2020) was estimated at 760.5 per 100,000 inhabitants, and age-standardized prevalence (2020) was 664.6 (male 595.7, female 711.0). Monotherapy was the most frequent way to treat AD (86.2%), in comparison with dual therapy (13.8%); rivastigmine was the most prescribed treatment (37.3%), followed by memantine (36.4%) and donepezil (33.0%). Rivastigmine was also the most utilized medication in newly treated patients (46.7%), followed by donepezil (29.8%), although donepezil persistence was longer (22.5 vs. 20.6 months). Overall, donepezil 10 mg, rivastigmine 9.5 mg, and memantine 20 mg were the most prescribed presentations. The incidence rate of AD decreased from 148.1/100,000 (95% confidence interval [CI] 147.0-149.2) in 2019 to 118.4/100,000 (95% CI 117.5-119.4) in 2020.

CONCLUSIONS

The obtained prevalence of AD-treated patients was consistent with previous face-to-face studies. In contrast with previous studies, rivastigmine, rather than donepezil, was the most frequent treatment. A decrease in the incidence of AD-treated patients was observed during 2020 in comparison with 2019, presumably due to the significant impact of the COVID-19 pandemic on both diagnosis and treatment. EMR databases emerge as valuable tools to monitor in real time the incidence and management of medical conditions in the population, as well as to assess the health impact of global contingencies and interventions.

Association of Fruit and Vegetable Consumption With Mild Cognitive Impairment in Low- and Middle-Income Countries

BACKGROUND

Inadequate fruit and vegetable intake may be associated with cognitive decline but its association with mild cognitive impairment (MCI; a preclinical stage of dementia) is largely unknown. Therefore, we examined the association of fruit and vegetable consumption with MCI among middle-aged and older adults from low- and middle-income countries (LMICs).

METHODS

Cross-sectional, nationally representative data from the WHO Study on global AGEing and adult health were analyzed. MCI was defined using the National Institute on Aging-Alzheimer's Association criteria. Quintiles of vegetable and fruit consumption were created based on the number of servings consumed on a typical day. Multivariable logistic regression analysis was conducted.

RESULTS

Data on 32 715 individuals aged ≥50 years were analyzed (mean [standard deviation] age 62.1 [15.6] years; 51.7% females). Greater fruit consumption was dose-dependently associated with lower odds for MCI. For example, the highest quintile (vs lowest) had 47% lower odds for MCI (odds ratio [OR] = 0.53; 95% confidence interval [CI] = 0.43-0.66). For vegetable consumption, compared to the lowest quintile, the second to fourth quintiles had significant 38%-44% lower odds for MCI but there was no significant difference for the highest quintile (OR = 0.82; 95% CI = 0.59-1.15).

CONCLUSIONS

Higher fruit and vegetable consumption was associated with lower odds for MCI among middle-aged and older adults from LMICs, but no significant differences were found between the highest and lowest quintiles of vegetable consumption. Future longitudinal studies are required to explore these findings in more depth, and mechanistic studies are required to elucidate on the observed possible U-shaped association between vegetable consumption and MCI.

Learning to PERSEVERE: A pilot study of peer mentor support and caregiver education in Lewy body dementia

BACKGROUND

Lewy Body Disease (LBD) is the second most common neurodegenerative disorder. Despite high family caregiver strain and adverse patient and caregiver outcomes, few interventions exist for LBD family caregivers. Based on a successful peer mentoring pilot study in advanced Parkinson's Disease, we revised the curriculum of this peer-led educational intervention incorporating LBD caregiver input.

OBJECTIVE

We assessed feasibility of a peer mentor-led educational intervention and its impact on LBD family caregivers' knowledge, dementia attitudes, and mastery.

METHODS

Using community-based participatory research, we refined a 16-week peer mentoring intervention and recruited caregivers online through national foundations. Experienced LBD caregiver mentors were trained and matched with newer caregiver mentees with whom they spoke weekly for 16 weeks, supported by the intervention curriculum. We measured intervention fidelity biweekly, program satisfaction, and change in LBD knowledge, dementia attitudes, and caregiving mastery before and after the 16-week intervention.

RESULTS

Thirty mentor-mentee pairs completed a median of 15 calls (range: 8-19; 424 total calls; median 45 min each). As satisfaction indicators, participants rated 95.3% of calls as useful, and at week 16, all participants indicated they would recommend the intervention to other caregivers. Mentees' knowledge and dementia attitudes improved by 13% (p < 0.05) and 7% (p < 0.001), respectively. Training improved mentors' LBD knowledge by 32% (p < 0.0001) and dementia attitudes by 2.5% (p < 0.001). Neither mentor nor mentee mastery changed significantly (p = 0.36, respectively).

CONCLUSIONS

This LBD caregiver-designed and -led intervention was feasible, well-received, and effective in improving knowledge and dementia attitudes in both seasoned and newer caregivers.

TRIAL REGISTRATION

https://clinicaltrials.gov/ct2/show/NCT04649164ClinicalTrials.gov Identifier: NCT04649164; December 2, 2020.

Biochemical profiling of berberine-enriched extract in aluminum chloride induced oxidative damage and neuroinflammation

Despite the numerous treatment strategies used for Alzheimer's disease (AD), only a few cholinesterase inhibitor drugs, such as memantine, are effective in symptomatically relieving the hallmarks of AD, providing momentary recovery of memory and cognitive decline. These available drugs do not treat the underlying causes of AD, and their chronic use is associated with serious adverse effects and disease progression. Berberine is an isoquinoline alkaloid that has been reported to possess therapeutic potential against AD. Therefore, its activity was evaluated against an aluminum chloride (AlCl3)-induced AD rat model, and a berberine-enriched extract (BEE) was used to determine if its activity is equivalent to pure berberine (PB). The rats were administered 300 mg/kg of oral AlCl3 to induce AD and were then treated with oral PB at a dosage of 50 mg/kg, BEE at a dosage of 50 mg/kg, and rivastigmine at a dosage of 1 mg/kg as a standard drug for 21 days. In this study, various parameters were assessed to evaluate cognitive functions, such as behavioral analysis, antioxidant enzyme levels, acetylcholinesterase (AChE) activity, proinflammatory cytokine levels, real-time polymerase chain reaction (RT-PCR) analysis of different biomarkers (AChE, IL-1α, IL-1β, BACE-1, TNF-α) linked to AD, and histopathological changes in the rats' brains. After 21 days, the disease control group showed a significant decline in cognitive function, decreased levels of antioxidant enzymes, upregulated activity of the AChE enzyme, increased levels of proinflammatory cytokines, and marked elevation in mRNA expression of AD-associated biomarkers. On the other hand, the treatment groups showed significant improvements in memory deficits, elevated levels of antioxidant enzymes, reduced levels of proinflammatory cytokines, decreased AChE activity, and significant downregulation of the expression of predefined biomarkers. Histological examination of the treatment groups showed less neuroinflammation and fewer amyloid plaques compared to the disease control group. In conclusion, both PB and BEE have comparable neuroprotective potential to mitigate the pathological hallmarks of AD. However, controlled clinical trials are needed to assess their efficacy and safety.

Exploring the Causal Relationship Between Telomere Biology and Alzheimer's Disease

Telomeres, also known as the "protective caps" of our chromosomes, shorten with each cell cycle due to the end replication problem. This process, termed telomere attrition, is associated with many age-related disorders, such as Alzheimer's disease (AD). Despite the numerous studies conducted in this field, the role of telomere attrition in the onset of the disease remains unclear. To investigate the causal relationship between short telomeres and AD, this review aims to highlight the primary factors that regulate telomere length and maintain its integrity, with an additional outlook on the role of oxidative stress, which is commonly associated with aging and molecular damage. Although some findings thus far might be contradictory, telomere attrition likely plays a crucial role in the progression of AD due to its close association with oxidative stress. The currently available treatments for AD are only symptomatic without affecting the progression of the disease. The components of telomere biology discussed in this paper have previously been studied as an alternative treatment option for several diseases and have exhibited promising in vitro and in vivo results. Hence, this should provide a basis for future research to develop a potential therapeutic strategy for AD. (Created with BioRender.com).

Antidiabetic agents as a novel treatment for Alzheimer's and Parkinson's disease

Therapeutic strategies for neurodegenerative disorders have commonly targeted individual aspects of the disease pathogenesis to little success. Neurodegenerative diseases, including Alzheimer's disease (AD) and Parkinson's disease (PD), are characterized by several pathological features. In AD and PD, there is an abnormal accumulation of toxic proteins, increased inflammation, decreased synaptic function, neuronal loss, increased astrocyte activation, and perhaps a state of insulin resistance. Epidemiological evidence has revealed a link between AD/PD and type 2 diabetes mellitus, with these disorders sharing some pathological commonalities. Such a link has opened up a promising avenue for repurposing antidiabetic agents in the treatment of neurodegenerative disorders. A successful therapeutic strategy for AD/PD would likely require a single or several agents which target the separate pathological processes in the disease. Targeting cerebral insulin signalling produces numerous neuroprotective effects in preclinical AD/PD brain models. Clinical trials have shown the promise of approved diabetic compounds in improving motor symptoms of PD and preventing neurodegenerative decline, with numerous further phase II trials and phase III trials underway in AD and PD populations. Alongside insulin signalling, targeting incretin receptors in the brain represents one of the most promising strategies for repurposing currently available agents for the treatment of AD/PD. Most notably, glucagon-like-peptide-1 (GLP-1) receptor agonists have displayed impressive clinical potential in preclinical and early clinical studies. In AD the GLP-1 receptor agonist, liraglutide, has been demonstrated to improve cerebral glucose metabolism and functional connectivity in small-scale pilot trials. Whilst in PD, the GLP-1 receptor agonist exenatide is effective in restoring motor function and cognition. Targeting brain incretin receptors reduces inflammation, inhibits apoptosis, prevents toxic protein aggregation, enhances long-term potentiation and autophagy as well as restores dysfunctional insulin signalling. Support is also increasing for the use of additional approved diabetic treatments, including intranasal insulin, metformin hydrochloride, peroxisome proliferator-activated nuclear receptor γ agonists, amylin analogs, and protein tyrosine phosphatase 1B inhibitors which are in the investigation for deployment in PD and AD treatment. As such, we provide a comprehensive review of several promising anti-diabetic agents for the treatment of AD and PD.

Comparative Analysis on the Policy Approaches in the National Dementia Plans of G7 Countries and Korea and Their Implementation

BACKGROUND

The World Health Organization (WHO) proposed a global action plan for dementia and aimed to have 75% of their member states formulating National Dementia Plans (NDPs) by 2025. The Organization for Economic Cooperation and Development (OECD) proposed the ten key objectives of dementia policy in 2015. Among previous studies on NDPs, few studies have investigated measures for proper implementation of NDPs. This study aimed to compare the implementation basis and specific action plans of NDPs between the G7 countries and South Korea.

METHODS

We investigated the measures for proper implementation of the NDPs of G7 countries and South Korea. To compare the specific policy approaches, the seven action areas of the WHO action plan and the ten key objectives of dementia policy proposed by the OECD were integrated into 11 targets (prevention, diagnosis, awareness, caregiver support, appropriate environments, long-term care, health service, end-of-life care, care coordination, research and technology, information systems).

RESULTS

Although most NDPs included specific action plans of the 11 targets, caregiver support, safe environments, healthcare services, and end-of-life care were lacking in some NDPs. For implementation, some countries reinforced the policy priority of their NDPs by timely updates, evaluation, legislations, or head-of-state leadership. However, only three countries had a legislative basis, and three countries included outcome measures in their latest NDP.

CONCLUSION

Effective measures for feasible implementation are needed. The WHO should promote not only the establishment of NDPs, but also their proper implementation.

The effects of high plasma levels of Aβ1-42 on mononuclear macrophage in mouse models of Alzheimer's disease

More and more evidences are proving that microglia play a crucial role in the pathogenesis of Alzheimer's disease (AD) and the plasma Aβ_1-42 levels significantly increased 15 years before the onset of dominantly inherited AD. However, the effects of high plasma levels of Aβ_1-42 on mononuclear macrophage, the peripheral counterparts of microglia, remain unclear. In the present study, we used APP/PS1 transgenic (Tg) mice and a parabiotic model of wild type (Wt) mice and Tg mice (Parabiotic Wt-Tg, Pa (Wt-Tg)) to investigate the effects of high plasma levels of Aβ_1-42 on peripheral mononuclear macrophage. Our results showed that in the early stage of Tg mice (7 months) and Pa (Wt-Tg) mice (4 months), the proportions of pro-inflammatory macrophages in peritoneal cavity, myeloid derived suppressor cells (MDSCs) in spleen, granulocyte-monocyte progenitors (GMPs) in bone marrow, and the plasma levels of interleukin-6 (IL-6) were significantly decreased. While the proportions of pro-inflammatory macrophages, MDSCs, GMPs, and the plasma levels of IL-6 and tumor necrosis factor (TNF)-α, as well as the numbers of bone marrow-derived macrophages (BMDMs) in mice brain were increased in the late stage of Tg mice (11 months) and Pa (Wt-Tg) mice (8 months). In addition, the proportions of monocytes in spleen and the proliferation of bone marrow cells (BMCs) were enhanced consistently, and the phagocytic function of macrophages kept stably after high plasma levels of Aβ_1-42 sustaining stimulation. These results demonstrated that high plasma levels of Aβ_1-42 play a biphasic regulating role at different stages of the disease, namely inhibiting effects on peripheral pro-inflammatory macrophages in the early stage of AD model, while promoting effects in the late stage of AD model. The mechanism behind this may be associated with their effects on MDSCs in spleen and myeloid progenitor cells in bone marrow. Therefore, intervening the effects of plasma Aβ_1-42 on pro-inflammatory macrophages might offer a new therapeutic approach to AD.

The effect of the leisure activities based on chess and cards for improving cognition of older adults: study protocol for a cluster randomized controlled trial

BACKGROUND

With the increase in age, the probability of cognitive impairment in the older people is increasing. More and more evidence shows that participating in leisure activities, especially chess and cards, is beneficial to the cognition and mental state of the older people. But the evidence for causal inference is limited. There is a need to conduct a fully powered randomized controlled trial (RCT) and long-term follow-up to test the effectiveness of intervention measures in improving cognitive function and mental state. This paper describes the methodology of a cluster RCT designed to determine the effect of chess and cards leisure activities on the cognitive function of the older people over 60 years old.

METHODS/DESIGN

A cluster RCT consisting of 8 clusters will be conducted in four regions of Ningxia, China (Helan, Litong, Qingtongxia, and Shapotou). Clusters will be randomly assigned to the advocacy intervention group, which is also delivered with free leisure activities tools (chess and cards), or the control group. A baseline survey will be conducted before the intervention. A mid-term and final survey will be carried out twelve and twenty-four months after the intervention, respectively. The primary outcome is a change in cognitive function, and the secondary outcomes are changes in anxiety, depression, and loneliness.

DISCUSSION

The results of this RCT will be helpful to (1) confirm the effectiveness of chess and cards leisure activities in improving the cognitive function of the older people over 60 years old; (2) determine the relationship between the frequency and duration of chess and cards leisure activities and cognitive function; (3) provide evidence of promoting participation in leisure activities through education campaigns and free provision of chess and cards tools; and (4) provide valuable information for successful aging.

TRIAL REGISTRATION

Chinese Clinical Trial Registry: ChiCTR2200066817. Registered on 19 December 2022.

Association between Mobile Phone Use and Incidence of Dementia: A Prospective Cohort Study Using the UK Biobank

INTRODUCTION

The rapid growth in mobile phone use has led to public concern about its potential effects on the risk of dementia. This study aimed to investigate the association between mobile phone use in daily life and the risk of dementia incidence in community-dwelling adults based on the data from the UK Biobank.

METHODS

Participants in the UK Biobank aged 60 years or older with no diagnosis of dementia at the time of recruitment were included in this prospective cohort study. A Cox regression model adjusted for sociodemographic characteristics, general health factors, mental health, lifestyle factors, comorbidities, and medication use was used to estimate the hazard ratio (HR) and confidence interval (CI) of the association between mobile phone use and dementia risk.

RESULTS

The final analyses included 213,181 participants. During a median follow-up period of 12.4 years, 6,344 cases of incident dementia occurred. Mobile phone use displayed a modest association with lower risk of dementia incidence, with HRs of 0.85 (95% CI: 0.79-0.91), 0.85 (95% CI: 0.80-0.91), 0.78 (95% CI: 0.71-0.86), 0.86 (95% CI: 0.77-0.96), and 0.83 (95% CI: 0.70-0.98) for participants who reported phone call usage of fewer than 5 min, 5-29 min, 30-59 min, 1-3 h, and more than 3 h per week, respectively, compared with nonusers. In addition, the proportions of the association medicated by family/friend visits and other leisure/social activities were 2.62% (95% CI: -0.64-6.51) and 2.22% (95% CI: 1.12-4.12), respectively.

CONCLUSIONS

Daily mobile phone use is significantly associated with a reduced risk of incident dementia in community-dwelling adults in the UK Biobank population. This association seems to be mediated by improved social and mental activities.

The spatial distribution of coupling between tau and neurodegeneration in amyloid-β positive mild cognitive impairment

Synergies between amyloid-β (Aβ), tau, and neurodegeneration persist along the Alzheimer's disease (AD) continuum. This study aimed to evaluate the extent of spatial coupling between tau and neurodegeneration (atrophy) and its relation to Aβ positivity in mild cognitive impairment (MCI). Data from 409 subjects were included (95 cognitively normal controls, 158 Aβ positive (Aβ+) MCI, and 156 Aβ negative (Aβ-) MCI) Florbetapir PET, Flortaucipir PET, and structural MRI were used as biomarkers for Aβ, tau and atrophy, respectively. Individual correlation matrices for tau load and atrophy were used to layer a multilayer network, with separate layers for tau and atrophy. A measure of coupling between corresponding regions of interest/nodes in the tau and atrophy layers was computed, as a function of Aβ positivity. The extent to which tau-atrophy coupling mediated associations between Aβ burden and cognitive decline was also evaluated. Heightened coupling between tau and atrophy in Aβ+ MCI was found primarily in the entorhinal and hippocampal regions (i.e., in regions corresponding to Braak stages I/II), and to a lesser extent in limbic and neocortical regions (i.e., corresponding to later Braak stages). Coupling strengths in the right middle temporal and inferior temporal gyri mediated the association between Aβ burden and cognition in this sample. Higher coupling between tau and atrophy in Aβ+ MCI is primarily evident in regions corresponding to early Braak stages and relates to overall cognitive decline. Coupling in neocortical regions is more restricted in MCI.

An enquiry to the role of CB1 receptors in neurodegeneration

Neurodegenerative disorders are debilitating conditions that impair patient quality of life and that represent heavy social-economic burdens to society. Whereas the root of some of these brain illnesses lies in autosomal inheritance, the origin of most of these neuropathologies is scantly understood. Similarly, the cellular and molecular substrates explaining the progressive loss of brain functions remains to be fully described too. Indeed, the study of brain neurodegeneration has resulted in a complex picture, composed of a myriad of altered processes that include broken brain bioenergetics, widespread neuroinflammation and aberrant activity of signaling pathways. In this context, several lines of research have shown that the endocannabinoid system (ECS) and its main signaling hub, the type-1 cannabinoid (CB1) receptor are altered in diverse neurodegenerative disorders. However, some of these data are conflictive or poorly described. In this review, we summarize the findings about the alterations in ECS and CB1 receptors signaling in three representative brain illnesses, the Alzheimer's, Parkinson's and Huntington's diseases, and we discuss the relevance of these studies in understanding neurodegeneration development and progression, with a special focus on astrocyte function. Noteworthy, the analysis of ECS defects in neurodegeneration warrant much more studies, as our conceptual understanding of ECS function has evolved quickly in the last years, which now include glia cells and the subcellular-specific CB1 receptors signaling as critical players of brain functions.

The Association Between Adverse Childhood Experiences and Late-Life Cognition: A Systematic Review of Cross-Sectional and Case-Control Studies

BACKGROUND AND OBJECTIVES

Adverse childhood experiences (ACEs) are a recognized risk factor for unfavorable health outcomes. No prior systematic review has explored the association between ACEs and cognition in late life, a critical period for cognitive fluctuation. The objective of this review is to address the following research question: What is the association between ACEs and late-life cognition?

RESEARCH DESIGN AND METHODS

Articles were obtained from PubMed, PsycINFO, and Scopus. The last search was performed in May 2021. Eligible articles examined the association between exposure to at least 1 ACE and the outcome of late-life cognition, measured either by cognitive testing or the presence/absence of a neurocognitive disorder. Data were synthesized narratively using the synthesis without meta-analysis guidelines, and the risk of bias was assessed using the Newcastle-Ottawa Scale (NOS) and Adapted NOS.

RESULTS

Twenty articles representing 18 unique studies were included in the narrative synthesis. Associations with lower late-life cognition were reported for: childhood maternal death, parental divorce, physical neglect, emotional neglect, physical abuse, and combinations of ACEs. However, most results were statistically nonsignificant, and many were unlikely to be clinically important.

DISCUSSION AND IMPLICATIONS

We found an association between ACEs and late-life cognition. However, the direction and magnitude of association varied between and within types of ACEs and measures of cognitive function. Most included articles had a moderate risk of bias. This review is the first attempt to synthesize the literature on this topic and it outlines the next steps to improve the evidence base in the area.

A task force for diagnosis and treatment of people with Alzheimer's disease in Latin America

Alzheimer's disease (AD) represents a substantial burden to patients, their caregivers, health systems, and society in Latin America and the Caribbean (LAC). This impact is exacerbated by limited access to diagnosis, specialized care, and therapies for AD within and among nations. The region has varied geographic, ethnic, cultural, and economic conditions, which create unique challenges to AD diagnosis and management. To address these issues, the Americas Health Foundation convened a panel of eight neurologists, geriatricians, and psychiatrists from Argentina, Brazil, Colombia, Ecuador, Guatemala, Mexico, and Peru who are experts in AD for a three-day virtual meeting to discuss best practices for AD diagnosis and treatment in LAC and create a manuscript offering recommendations to address identified barriers. In LAC, several barriers hamper diagnosing and treating people with dementia. These barriers include access to healthcare, fragmented healthcare systems, limited research funding, unstandardized diagnosis and treatment, genetic heterogeneity, and varying social determinants of health. Additional training for physicians and other healthcare workers at the primary care level, region-specific or adequately adapted cognitive tests, increased public healthcare insurance coverage of testing and treatment, and dedicated search strategies to detect populations with gene variants associated with AD are among the recommendations to improve the landscape of AD.

Advances in diagnosing mild cognitive impairment and Alzheimer's disease using 11C-PIB- PET/CT and common neuropsychological tests

Alzheimer's disease (AD) is a critical health issue worldwide that has a negative impact on patients' quality of life, as well as on caregivers, society, and the environment. Positron emission tomography (PET)/computed tomography (CT) and neuropsychological scales can be used to identify AD and mild cognitive impairment (MCI) early, provide a differential diagnosis, and offer early therapies to impede the course of the illness. However, there are few reports of large-scale ¹¹C-PIB-PET/CT investigations that focus on the pathology of AD and MCI. Therefore, further research is needed to determine how neuropsychological test scales and PET/CT measurements of disease progression interact.

Adverse events in older adults and the risk of dementia and cognitive decline

Background

Increasing evidence suggests that stress could be a risk factor for dementia but this might vary by gender. This study investigated whether adverse life events were associated with cognitive decline and dementia in later-life, separately in men and women.

Methods

Participants were 12,789 community-dwelling Australians aged ≥ 70 years. Ten common adverse events in later-life were self-reported. Cognitive decline was defined as a 1.5 SD decline from participants' baseline score in tests of global cognition, psychomotor speed, episodic memory, and executive functioning, which were assessed regularly over a maximum of 10.3 years. Dementia was diagnosed according to DSM-IV criteria.

Results

An increased risk of dementia was observed in participants who experienced the death of a spouse/partner (HR: 1.72, 95% CI: 1.17 - 2.52) and for individuals who experienced major financial problems (HR: 1.53, 95% CI: 1.05 - 2.23). The latter also increased the risk of cognitive decline in men specifically (HR: 1.43, 95% CI: 1.10 - 1.86). In contrast, some events for women were associated with a reduced risk of dementia (e.g. close family or friends lost their job/retired (HR: 0.62, 95% CI: 0.40-0.95)).

Limitations

Events including major money problems may result from prodromal dementia symptoms, thus reverse causation needs to be considered.

Conclusions

Adverse life events may influence dementia risk in older adults, but associations vary depending on the nature of the event, and across genders. These findings support the need for early interventions in older people who have experienced adversities, particularly for the death of a loved one.

The Prevalence of Comorbidities and Associated Factors among Patients with Dementia in the Indian Setting: Meta-analysis of Observational Studies

BACKGROUND

Patients with dementia usually have multiple comorbidities. The presence of comorbidities may exacerbate the progression of dementia and decreases the patient's ability to participate in health maintenance activities. However, there is hardly any meta-analysis estimating the magnitude of comorbidities among patients with dementia in the Indian context.

METHODS

We searched PubMed, Scopus, and Google Scholar, and relevant studies conducted in India were included. The risk of bias was assessed and a random-effects meta-analysis model was used in which I2 statistics were calculated to measure heterogeneity among studies.

RESULTS

Fourteen studies were included in the meta-analysis based on the inclusion and exclusion criteria. Altogether, we found the coexistence of comorbid conditions such as hypertension (51.10%), diabetes (27.58%), stroke (15.99%), and factors like tobacco use (26.81 %) and alcohol use (9.19%) among patients with dementia in this setting. The level of heterogeneity was high due to differences in the methodologies in the included studies.

CONCLUSIONS

Our study found hypertension as the most common comorbid condition among patients with dementia in India. The observed lacuna of methodological limitations in the studies included in the current meta-analysis provides the urgent need for good quality research to successfully meet the challenges ahead while devising appropriate strategies to treat the comorbidities among patients with dementia.

Examination of potentially modifiable dementia risk factors across the adult life course: The Framingham Heart Study

INTRODUCTION

We examined for associations between potentially modifiable risk factors across the adult life course and incident dementia.

METHODS

Participants from the Framingham Heart Study were included (n = 4015). Potential modifiable risk factors included education, alcohol intake, smoking, body mass index (BMI), physical activity, social network, diabetes, and hypertension. Cox models were used to examine associations between each factor and incident dementia, stratified by early adult life (33-44 years), midlife (45-65 years), and late life (66-80 years).

RESULTS

Increased dementia risk was associated with diabetes (hazard ratio [HR] = 1.62; 95% confidence interval [CI] = 1.07-2.46) and physical inactivity (HR = 1.57; 95% CI = 1.12-2.20) in midlife, and with obesity (HR = 1.76; 95% CI = 1.08-2.87) in late life. Having multiple potential modifiable risk factors in midlife and late life was associated with greater risk.

DISCUSSION

Potentially modifiable risk factors individually have limited impact on dementia risk in this population across the adult life course, although in combination they may have a synergistic effect.

HIGHLIGHTS

Diabetes and physical inactivity in midlife is associated with increased dementia risk. Obesity in late life is associated with increased dementia risk. Having more potentially modifiable risk factors in midlife and late life is associated with greater dementia risk.

Mortality and Discharge Location of Intensive Care Patients With Alzheimer Disease and Related Dementia

BACKGROUND

Intensive care unit (ICU) utilization has increased among patients with Alzheimer disease and related dementia (ADRD), although outcomes are poor.

OBJECTIVES

To compare ICU discharge location and subsequent mortality between patients with and patients without ADRD enrolled in Medicare Advantage.

METHODS

This observational study used Optum's Clinformatics Data Mart Database from years 2016 to 2019 and included adults aged >67 years with continuous Medicare Advantage coverage and a first ICU admission in 2018. Alzheimer disease and related dementia and comorbid conditions were identified from claims. Outcomes included discharge location (home vs other facilities) and mortality (within the same calendar month of discharge and within 12 months after discharge).

RESULTS

A total of 145 342 adults met inclusion criteria; 10.5% had ADRD and were likely to be older, female, and have more comorbid conditions. Only 37.6% of patients with ADRD were discharged home versus 68.6% of patients who did not have ADRD (odds ratio [OR], 0.40; 95% CI, 0.38-0.41). Both death in the same month as discharge (19.9% vs 10.3%; OR, 1.54; 95% CI, 1.47-1.62) and death in the 12 months after discharge (50.8% vs 26.2%; OR, 1.95; 95% CI, 1.88-2.02) were twice as common among patients with ADRD.

CONCLUSIONS

Patients with ADRD have lower home discharge rates and greater mortality after an ICU stay than patients without ADRD.

Effects of three kinds of anti-amyloid-β drugs on clinical, biomarker, neuroimaging outcomes and safety indexes: A systematic review and meta-analysis of phase II/III clinical trials in Alzheimer's disease

OBJECTIVE

To investigate the effects of the three kinds of anti-amyloid-β (Aβ) drugs on cognitive and other functions, fluid and neuroimaging biomarkers, and safety on patients with Alzheimer's disease (AD), and rank the three kinds of anti-Aβ drugs.

METHODS

We searched Medline, Embase, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, and AlzForum from inception to January 21, 2023 to include randomized controlled clinical trials. Random effects meta-analyses were performed.

RESULTS

Forty-one clinical trials (20929 participants, 9167 male) were included. Anti-Aβ drugs had significant but relatively low efficacy in preventing cognitive decline (ADAS-Cog SMD -0.07, 95% CI: -0.10 to -0.03, p < 0.001; CDR-SOB -0.05, -0.09 to -0.01, p = 0.017). Instrumental variable meta-analysis and trial sequential analysis confirmed the reliability of the pooled estimation. Beneficial effects were also observed by assessing other cognitive and activity of daily living scales and biomarkers, with acceptable safety of anti-Aβ drugs. Meta-regression demonstrated significant association between higher baseline mini-mental statement examination scores (MMSE) and better cognitive protective effects on cognitive function (ADAS-Cog β: -0.02, -0.05 to 0.00, p = 0.017) and clearance of pathological productions of anti-Aβ drugs. Network meta-analysis ranked the passive immunotherapy drugs to have the best cognitive efficacy, followed by active immunotherapy and small molecule drugs.

CONCLUSION

Anti-Aβ drugs have relatively low efficacy in preventing cognitive decline, and they reduce pathological productions with acceptable safety. Patients with higher baseline MMSE scores benefit more from anti-Aβ drugs. Passive immunotherapy anti-Aβ drugs show relatively better efficacy than active immunotherapy and small molecule anti-Aβ drugs.

Large Discrepancies in Dementia Mortality Reported in Vital Statistics: The Need for Improved Data to Inform Policy

PURPOSE

There is limited understanding of the intercountry comparability of dementia mortality data. This study compares reported dementia mortality in national vital statistics between countries and over time. In countries with low dementia reporting, this study identifies other causes to which dementia may be misclassified.

METHODS

Using the World Health Organization (WHO) Mortality Database, we calculated the ratio of reported to expected (Global Burden of Disease estimated) age-standardized dementia death rates in 90 countries from 2000 to 2019. Other causes to which dementia may be misclassified were identified as having relatively high cause fractions compared with other countries.

PATIENTS

No patients were involved.

RESULTS

There is a large intercountry variation in reported dementia mortality rates. The ratio of reported to expected dementia mortality exceeded 100% in high-income countries but was below 50% in other super regions. In countries with low reported dementia mortality, cardiovascular diseases, ill-defined causes, and pneumonia have relatively high cause fractions and may be misclassified from dementia.

DISCUSSION

Large discrepancies in dementia mortality reporting between countries, including often implausibly low reported mortality, makes comparison extremely difficult. Improved guidance for and training of certifiers and the use of multiple cause-of-death data can help strengthen the policy utility of dementia mortality data.

Hospitalization and emergency department visits associated with potentially inappropriate medication in older adults: self-controlled case series analysis

Introduction

Potentially inappropriate medications (PIM) and resulting adverse health outcomes in older adults are a common occurrence. However, PIM prescriptions are still frequent for vulnerable older adults. Here, we sought to estimate the risk of hospitalization and emergency department (ED) visits associated with PIM prescriptions over different exposure periods and PIM drug categories.

Methods

We used the National Health Insurance Service-Elderly Cohort Database (NHIS-ECDB) to construct the cohort and implemented a Self-Controlled Case Series (SCCS) method. Hospitalization or ED visits during the exposure and post-exposure periods were compared to those during the non-exposure period, and six PIM drug categories were evaluated. A conditional Poisson regression model was applied, and the risk of outcomes was presented as the incidence rate ratio (IRR). All potential time-varying covariates were adjusted by year. A total of 43,942 older adults aged ≥65 y who had at least one PIM prescription and the events of either hospitalization or ED visits between Jan 2016 and Dec 2019 were selected..

Results

Mean days of each exposure period was 46 d (±123); risk was highest in exposure1 (1-7 d, 37.8%), whereas it was similar during exposure2 (15-28 d), and exposure3 (29-56 d) (16.6%). The mean number of total PIM drugs administered during the study period was 7.34 (±4.60). Both hospitalization and ED visits were significantly higher in both exposure (adjusted IRR 2.14, 95% Confidence Interval (CI):2.11-2.17) and post-exposure periods (adjusted IRR 1.41, 95% CI:1.38-1.44) in comparison to non-exposure period. The risk of adverse health outcomes was highest during the first exposure period (1-14 d), but decreased gradually over time. Among the PIM categories, pain medication was used the most, followed by anticholinergics. All PIM categories significantly increased the risk of hospitalization and ED visits, ranging from 1.18 (other PIM) to 2.85 (pain medication). Sensitivity analyses using the first incidence of PIM exposure demonstrated similar results. All PIM categories significantly increased the risk of hospitalization and ED visits, with the initial period of PIM prescriptions showing the highest risk. In subgroup analysis stratified by the number of medications, PIM effects on the risk of hospitalization and ED visits remained significant but gradually attenuated by the increased number of medications.

Discussion

Therefore, the development of deprescribing strategies to control PIM and polypharmacy collectively is urgent and essential.

Growing old in China in socioeconomic and epidemiological context: systematic review of social care policy for older people

BACKGROUND

From 2020 to 2050, China's population aged ≥65 years old is estimated to more than double from 172 million (12·0%) to 366 million (26·0%). Some 10 million have Alzheimer's disease and related dementias, to approach 40 million by 2050. Critically, the population is ageing fast while China is still a middle-income country.

METHODS

Using official and population-level statistics, we summarise China's demographic and epidemiological trends relevant to ageing and health from 1970 to present, before examining key determinants of China's improving population health in a socioecological framework. We then explore how China is responding to the care needs of its older population by carrying out a systematic review to answer the question: 'what are the key policy challenges to China achieving an equitable nationwide long-term care system for older people?'. Databases were screened for records published between 1st June 2020 and 1st June 2022 in Mandarin Chinese or English, reflecting our focus on evidence published since introduction of China's second long-term care insurance pilot phase in 2020.

RESULTS

Rapid economic development and improved access to education has led to widescale internal migration. Changing fertility policies and household structures also pose considerable challenges to the traditional family care model. To deal with increasing need, China has piloted 49 alternative long-term care insurance systems. Our findings from 42 studies (n = 16 in Mandarin) highlight significant challenges in the provision of quality and quantity of care which suits the preference of users, varying eligibility for long-term care insurance and an inequitable distribution of cost burden. Key recommendations include increasing salaries to attract and retain staff, introduction of mandatory financial contributions from employees and a unified standard of disability with regular assessment. Strengthening support for family caregivers and improving smart old age care capacity can also support preferences to age at home.

CONCLUSIONS

China has yet to establish a sustainable funding mechanism, standardised eligibility criteria and a high-quality service delivery system. Its long-term care insurance pilot studies provide useful lessons for other middle-income countries facing similar challenges in terms of meeting the long-term care needs of their rapidly growing older populations.

Cohort profile: rationale and methods of UK Biobank repeat imaging study eye measures to study dementia

PURPOSE

The retina provides biomarkers of neuronal and vascular health that offer promising insights into cognitive ageing, mild cognitive impairment and dementia. This article described the rationale and methodology of eye and vision assessments with the aim of supporting the study of dementia in the UK Biobank Repeat Imaging study.

PARTICIPANTS

UK Biobank is a large-scale, multicentre, prospective cohort containing in-depth genetic, lifestyle, environmental and health information from half a million participants aged 40-69 enrolled in 2006-2010 across the UK. A subset (up to 60 000 participants) of the cohort will be invited to the UK Biobank Repeat Imaging Study to collect repeated brain, cardiac and abdominal MRI scans, whole-body dual-energy X-ray absorptiometry, carotid ultrasound, as well as retinal optical coherence tomography (OCT) and colour fundus photographs.

FINDINGS TO DATE

UK Biobank has helped make significant advances in understanding risk factors for many common diseases, including for dementia and cognitive decline. Ophthalmic genetic and epidemiology studies have also benefited from the unparalleled combination of very large numbers of participants, deep phenotyping and longitudinal follow-up of the cohort, with comprehensive health data linkage to disease outcomes. In addition, we have used UK Biobank data to describe the relationship between retinal structures, cognitive function and brain MRI-derived phenotypes.

FUTURE PLANS

The collection of eye-related data (eg, OCT), as part of the UK Biobank Repeat Imaging study, will take place in 2022-2028. The depth and breadth and longitudinal nature of this dataset, coupled with its open-access policy, will create a major new resource for dementia diagnostic discovery and to better understand its association with comorbid diseases. In addition, the broad and diverse data available in this study will support research into ophthalmic diseases and various other health outcomes beyond dementia.

Genome-wide meta-analysis of CSF biomarkers in Alzheimer's disease and Parkinson's disease cohorts

Background

Amyloid beta (Aβ), phosphorylated tau (p-tau), and total tau (t-tau) in cerebrospinal fluid are established biomarkers for Alzheimer's disease (AD). In other neurodegenerative diseases, such as Parkinson's disease (PD), these biomarkers have also been found to be altered, and the molecular mechanisms responsible for these alterations are still under investigation. Moreover, the interplay between these mechanisms and the diverse underlying disease states remains to be elucidated.

Objectives

To investigate genetic contributions to the AD biomarkers and assess the commonality and heterogeneity of the associations per underlying disease status.

Methods

We conducted GWAS for the AD biomarkers on subjects from the Parkinson's Progression Markers Initiative (PPMI), the Fox Investigation for New Discovery of Biomarkers (BioFIND), and the Alzheimer's Disease Neuroimaging Initiative (ADNI) and meta-analyzed with the largest AD GWAS.[7] We tested heterogeneity of associations of interest between different disease statuses (AD, PD, and control).

Results

We observed three GWAS signals: the APOE locus for Aβ, the 3q28 locus between GEMC1 and OSTN for p-tau and t-tau, and the 7p22 locus (top hit: rs60871478, an intronic variant for DNAAF5 , also known as HEATR2 ) for p-tau. The 7p22 locus is novel and co-localized with the brain DNAAF5 expression. While no heterogeneity from underlying disease status was observed for the above GWAS signals, some disease risk loci suggested disease specific associations with these biomarkers.

Conclusions

Our study identified a novel association at the intronic region of DNAAF5 associated with increased levels of p-tau across all diseases. We also observed some disease specific genetic associations with these biomarkers.

Ranking the risk factors for Alzheimer's disease; findings from the UK Biobank study

Background

The cause of the most common form of dementia, sporadic Alzheimer's disease (AD), remains unknown. This may reflect insufficiently powered studies to date for this multi-factorial disorder. The UK Biobank dataset presents a unique opportunity to rank known risk factors and determine novel variables.

Methods

A custom machine learning approach for high dimensionality data was applied to explore prospectively associations between AD in a sub-cohort of 156,209 UK Biobank participants aged 60-70 including more than 2,090 who were subsequently diagnosed with AD.

Results

After the possession of the APOE4 allele, the next highest ranked risk factors were other genetic variants within the TOMM40-APOE-APOC1 locus. When stratified by their apolipoprotein epsilon 4 (APOE4) carrier status, the most prominent risk factors in carriers were AST:ALT ratio, the "number of treatments/ medications" taken as well as "time spent in hospital" while protection was conferred by "Sleeplessness/Insomnia". In non-APOE carriers, lower socioeconomic status and fewer years of education were highly ranked but effect sizes were small relative to APOE4 carriers.

Conclusions

Possession of the APOE4 allele was confirmed as the most important risk factor in AD. Other TOMM40-APOE-APOC1 locus variants further moderate the risk of AD in APOE4 carriers. Liver pathology is a novel risk factor in APOE4 carriers while "Sleeplessness/Insomnia" is protective in AD irrespective of APOE4 status. Other factors such as "Number of treatments/ medications" suggest that multimorbidity is an important risk factor for AD. Future treatments aimed at co-morbidities, including liver disease, may concomitantly lower the risk of sporadic AD.

Mid-infrared chemical imaging of intracellular tau fibrils using fluorescence-guided computational photothermal microscopy

Amyloid proteins are associated with a broad spectrum of neurodegenerative diseases. However, it remains a grand challenge to extract molecular structure information from intracellular amyloid proteins in their native cellular environment. To address this challenge, we developed a computational chemical microscope integrating 3D mid-infrared photothermal imaging with fluorescence imaging, termed Fluorescence-guided Bond-Selective Intensity Diffraction Tomography (FBS-IDT). Based on a low-cost and simple optical design, FBS-IDT enables chemical-specific volumetric imaging and 3D site-specific mid-IR fingerprint spectroscopic analysis of tau fibrils, an important type of amyloid protein aggregates, in their intracellular environment. Label-free volumetric chemical imaging of human cells with/without seeded tau fibrils is demonstrated to show the potential correlation between lipid accumulation and tau aggregate formation. Depth-resolved mid-infrared fingerprint spectroscopy is performed to reveal the protein secondary structure of the intracellular tau fibrils. 3D visualization of the β-sheet for tau fibril structure is achieved.

Dementia Risk Models in an Australian First Nations Population: Cross-Sectional Associations and Preparation for Follow-Up

Background

Reducing the burden of dementia in First Nations populations may be addressed through developing population specific methods to quantify future risk of dementia.

Objective

To adapt existing dementia risk models to cross-sectional dementia prevalence data from a First Nations population in the Torres Strait region of Australia in preparation for follow-up of participants. To explore the diagnostic utility of these dementia risk models at detecting dementia.

Methods

A literature review to identify existing externally validated dementia risk models. Adapting these models to cross-sectional data and assessing their diagnostic utility through area under the receiver operating characteristic curve (AUROC) analyses and calibration using Hosmer-Lemeshow Chi².

Results

Seven risk models could be adapted to the study data. The Aging, Cognition and Dementia (AgeCoDe) study, the Framingham Heart Study (FHS), and the Brief Dementia Screening Indicator (BDSI) had moderate diagnostic utility in identifying dementia (i.e., AUROC >0.70) before and after points for older age were removed.

Conclusion

Seven existing dementia risk models could be adapted to this First Nations population, and three had some cross-sectional diagnostic utility. These models were designed to predict dementia incidence, so their applicability to identify prevalent cases would be limited. The risk scores derived in this study may have prognostic utility as participants are followed up over time. In the interim, this study highlights considerations when transporting and developing dementia risk models for First Nations populations.

The controversial effect of smoking and nicotine in SARS-CoV-2 infection

The effects of nicotine and cigarette smoke in many diseases, notably COVID-19 infection, are being debated more frequently. The current basic data for COVID-19 is increasing and indicating the higher risk of COVID-19 infections in smokers due to the overexpression of corresponding host receptors to viral entry. However, current multi-national epidemiological reports indicate a lower incidence of COVID-19 disease in smokers. Current data indicates that smokers are more susceptible to some diseases and more protective of some other. Interestingly, nicotine is also reported to play a dual role, being both inflammatory and anti-inflammatory. In the present study, we tried to investigate the effect of pure nicotine on various cells involved in COVID-19 infection. We followed an organ-based systematic approach to decipher the effect of nicotine in damaged organs corresponding to COVID-19 pathogenesis (12 related diseases). Considering that the effects of nicotine and cigarette smoke are different from each other, it is necessary to be careful in generalizing the effects of nicotine and cigarette to each other in the conducted researches. The generalization and the undifferentiation of nicotine from smoke is a significant bias. Moreover, different doses of nicotine stimulate different effects (dose-dependent response). In addition to further assessing the role of nicotine in COVID-19 infection and any other cases, a clever assessment of underlying diseases should also be considered to achieve a guideline for health providers and a personalized approach to treatment.

Population attributable fraction of hypertension for dementia: global, regional, and national estimates for 186 countries

Background

Quantifying the proportion of dementia attributable to highly prevalent modifiable risk factors, such as hypertension, is important in informing effective dementia prevention strategies. We aim to quantify the population attributable fraction (PAF) of hypertension for dementia (the proportion of dementia cases that would not occur if hypertension was eliminated) at global, regional, and national levels.

Methods

In this study, we searched international and governmental websites for global, regional, and national data reporting population hypertension (according to 10-year age categories) and dementia prevalence. MEDLINE was searched for studies reporting the risk of dementia from age at hypertension diagnosis from database inception to December 31, 2022. Longitudinal observational studies with >500 participants reporting hazard ratios by age at hypertension diagnosis for risk of future all-cause dementia were eligible for inclusion. Studies excluded had cross-sectional methodology, specific vascular dementia or 'cognitive impairment' outcomes, and no age-specific metrics of association reported. The PAF of hypertension for dementia was calculated globally and for each country and region worldwide.

Findings

Data from the Global Burden of Disease, United Nations Population Prospectus, NCD Risk Factor Collaboration, UK Biobank, and Atherosclerosis Risk in Communities Study were obtained. 186 countries reported dementia and hypertension prevalence data. The global PAF of hypertension for dementia was 15.8% [95% Credible Interval (CI), 8.8%-22.7%]. Latin America and the Caribbean (18.0% [95% CI, 9.4%-26.6%]), and Europe (17.2% [95% CI, 9.6%-24.7%]) had the highest PAF of hypertension for dementia. Hypertension diagnosed between the ages of 30-44 had the highest age-specific global attributable fraction for dementia (8.4% [95% CI, 3.4%-13.5%]), followed by ages 45-54 (2.92% [ 95% CI, 0.96%-4.88%]), 55-64 (2.59% [95% CI, 1.15%-4.03%]) and 65-74 (1.82% [95% CI, -2.31%-5.96%]).

Interpretation

The population attributable risk of hypertension for dementia is 15.8%, suggesting that optimal detection and treatment, particularly at midlife, has the potential to markedly reduce the global burden of dementia.

Funding

Wellcome Trust; Health Research Board of Ireland; Alzheimer's Association.

Dementias Among Older Males and Females in the U.S. Medicare System With and Without HIV

BACKGROUND

Despite the growing concern that people with HIV (PWH) will experience a disproportionate burden of dementia as they age, very few studies have examined the sex-specific prevalence of dementia, including Alzheimer disease and related dementias (AD/ADRD) among older PWH versus people without HIV (PWOH) using large national samples.

METHODS

We constructed successive cross-sectional cohorts including all PWH aged 65+ years from U.S. Medicare enrollees and PWOH in a 5% national sample of Medicare data from 2007 to 2019. All AD/ADRD cases were identified by ICD-9-CM/ICD-10-CM diagnosis codes. Prevalence of AD/ADRD was calculated for each calendar year by sex-age strata. Generalized estimating equations were used to assess factors associated with dementia and calculate the adjusted prevalence.

RESULTS

PWH had a higher prevalence of AD/ADRD, which increased over time compared with PWOH, especially among female beneficiaries and with increasing age. For example, among those aged 80+ years, the prevalence increased from 2007 to 2019 (females with HIV: 31.4%-44.1%; females without HIV: 27.4%-29.9%; males with HIV: 26.2%-33.3%; males without HIV: 21.0%-23.5%). After adjustment for demographics and comorbidities, the differences in dementia burden by HIV status remained, especially among older age groups.

CONCLUSIONS

Older Medicare enrollees with HIV had an increased dementia burden over time compared with those without HIV, especially women and older subjects. This underscores the need to develop tailored clinical practice guidelines that facilitate the integration of dementia and comorbidity screening, evaluation, and management into the routine primary care of aging PWH.

Effectiveness of exercise programmes in improving physical function and reducing behavioural symptoms of community living older adults with dementia living in Asia, and impact on their informal carers: A systematic review and meta-analysis

Background

There is a growing evidence on the benefits of exercise for older people living with dementia in developed countries. However, cultural, health-care systems and environmental differences may impact on the uptake of exercise and outcomes in different regions of the world.

Objective

This study synthesised the available evidence examining the effectiveness of exercise interventions on improving physical function and reducing behavioural symptoms in community-dwelling older people living with dementia in Asia, and the impact on their informal carers.

Methods

Six databases were searched to November 2021. Randomised controlled trials (RCTs) or quasi-experimental studies evaluating exercise interventions for community-dwelling older people with dementia living in Asia were included. The Cochrane risk-of-bias tool for randomised trials and Downs and Black checklist had been used to assess methodological quality of the studies. Meta-analyses using a fixed effects model assessed the effects of exercise interventions where sufficient data were available. Mean difference (MD) with 95% confidence interval (CI) was used to pool results.

Results

Nine studies (five RCTs) were included (Hong Kong-4, China-1, South Korea-2, Taiwan-1, Indonesia-1). Exercise improved dynamic balance [Functional Reach (2 studies, n = 111 people with dementia), MD = 2 . 61 , 95% CI (1.55, 3.67)], but not for the Berg Balance Scale (MD = 1 . 10 , 95% CI [-2.88, 5.07]), Timed Up and Go (MD =- 3 . 47 , 95% CI [-7.27, 0.33]) and 5 times sit to stand tests (MD =- 1 . 86 , 95% CI [-5.27, 1.54]). Single studies where data could not be pooled showed no effect of exercise on behavioural symptoms or impact on informal carers.

Conclusion

Exercise appeared to have a beneficial effect on improving balance performance among older people with dementia living in Asia, however, this evidence is limited and inconsistent, and should be interpreted with caution. Further high-quality large RCTs are necessary for advancing the evidence base of exercise interventions for this population.

Effects of vasicine in neuroinflammatory zebrafish model

Chronic neuroinflammation produces cytotoxic effects and aggravates neurodegeneration. Cognitive impairment was considered an early symptom of many neurodegenerative diseases. Therefore, it is of interest to evaluate the in-vivo efficacy of vasicine for treating neuroinflammation-induced cognitive impairments in the zebrafish model. The Neurobehavioral activity was evaluated with a dive tank test, swim motion test, plus maze test, turn angle test, and color preference test in three neuroinflammatory zebrafish models. Gene expression analysis was done for neuroinflammatory markers (IL-10, IL-15, IL-13, NogoA, Fetuin-A, BDNF, NAA, CXCL2, Osteopontin) using polymerase chain reaction and gel electrophoresis technique. Behavioral parameters and biochemical evaluations revealed that vasicine was effective in treatment against neuroinflammatory models of surgery, chemical, xenotransplantation. Attenuation of cognitive dysfunction in all three neuroinflammation zebrafish models by vasicine in this study may recommend vasicine as a potential molecule for treating neuroinflammatory and neurodegenerative diseases.

Urinary tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) and cognitive functioning in older adults: The National Health and Nutrition Examination Survey 2013-2014

INTRODUCTION

Tobacco contains carcinogens called tobacco-specific nitrosamines. Among the tobacco-specific nitrosamines, is nicotine-derived nitrosamine ketone (NNK) which produces the metabolite 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL). We aimed to examine the association between urinary tobacco-specific NNAL and cognitive functioning among older adults.

METHODS

A total of 1673 older adults aged ≥60 years from the National Health and Nutrition Examination Survey 2013-2014 were included. Urinary tobacco-specific NNAL was analyzed in the laboratory. Cognitive functioning was measured using the Consortium to Establish a Registry for Alzheimer's Disease Word Learning subtest (CERAD-WL) immediate and delayed memory tests, the Animal Fluency test (AFT), and the Digit Symbol Substitution Test (DSST). Test-specific and global cognition z-scores were calculated based on means and standard deviations of the cognitive test scores. Multivariable linear regression models were constructed to examine the independent association between quartiles of urinary tobacco-specific NNAL and cognitive test-specific and global cognition z-scores controlling for age, sex, race/ethnicity, education level, depressive symptoms, body mass index, systolic blood pressure, urinary creatinine, hypertension, diabetes, alcohol use, and smoking status.

RESULTS

About half of the participants (mean age 69.8 years) were female (52.1%), non-Hispanic White (48.3%), and completed some college and above (49.7%). Multivariable linear regression results showed that participants in the 4th quartile (highest quartile) of urinary NNAL, compared with those in the 1st quartile (lowest quartile), had lower DSST z-scores (β= -0.19; 95% CI: -0.34 - -0.04).

CONCLUSIONS

Tobacco-specific NNAL was negatively associated with processing speed, sustained attention, and working memory in older adults.

Deep Brain Stimulation beyond the Clinic: Navigating the Future of Parkinson's and Alzheimer's Disease Therapy

Deep brain stimulation (DBS) is a surgical procedure that uses electrical neuromodulation to target specific regions of the brain, showing potential in the treatment of neurodegenerative disorders such as Parkinson's disease (PD) and Alzheimer's disease (AD). Despite similarities in disease pathology, DBS is currently only approved for use in PD patients, with limited literature on its effectiveness in AD. While DBS has shown promise in ameliorating brain circuits in PD, further research is needed to determine the optimal parameters for DBS and address any potential side effects. This review emphasizes the need for foundational and clinical research on DBS in different brain regions to treat AD and recommends the development of a classification system for adverse effects. Furthermore, this review suggests the use of either a low-frequency system (LFS) or high-frequency system (HFS) depending on the specific symptoms of the patient for both PD and AD.

Senescence-related impairment of autophagy induces toxic intraneuronal amyloid-β accumulation in a mouse model of amyloid pathology

Aging is the main risk factor for Alzheimer's disease (AD) and other neurodegenerative pathologies, but the molecular and cellular changes underlying pathological aging of the nervous system are poorly understood. AD pathology seems to correlate with the appearance of cells that become senescent due to the progressive accumulation of cellular insults causing DNA damage. Senescence has also been shown to reduce the autophagic flux, a mechanism involved in clearing damaged proteins from the cell, and such impairment has been linked to AD pathogenesis. In this study, we investigated the role of cellular senescence on AD pathology by crossing a mouse model of AD-like amyloid-β (Aβ) pathology (5xFAD) with a mouse model of senescence that is genetically deficient for the RNA component of the telomerase (Terc^-/-). We studied changes in amyloid pathology, neurodegeneration, and the autophagy process in brain tissue samples and primary cultures derived from these mice by complementary biochemical and immunostaining approaches. Postmortem human brain samples were also processed to evaluate autophagy defects in AD patients. Our results show that accelerated senescence produces an early accumulation of intraneuronal Aβ in the subiculum and cortical layer V of 5xFAD mice. This correlates with a reduction in amyloid plaques and Aβ levels in connecting brain regions at a later disease stage. Neuronal loss was specifically observed in brain regions presenting intraneuronal Aβ and was linked to telomere attrition. Our results indicate that senescence affects intraneuronal Aβ accumulation by impairing autophagy function and that early autophagy defects can be found in the brains of AD patients. Together, these findings demonstrate the instrumental role of senescence in intraneuronal Aβ accumulation, which represents a key event in AD pathophysiology, and emphasize the correlation between the initial stages of amyloid pathology and defects in the autophagy flux.

ALTAI Tool for Assessing AI-Based Technologies: Lessons Learned and Recommendations from SHAPES Pilots

Across European countries, the SHAPES Project is piloting AI-based technologies that could improve healthcare delivery for older people over 60 years old. This article aims to present a study developed inside the SHAPES Project to find a theoretical framework focused on AI-assisted technology in healthcare for older people living in the home, to assess the SHAPES AI-based technologies using the ALTAI tool, and to derive ethical recommendations regarding AI-based technologies for ageing and healthcare. The study has highlighted concerns and reservations about AI-based technologies, namely dealing with living at home, mobility, accessibility, data exchange procedures in cross-board cases, interoperability, and security. A list of recommendations is built not only for the healthcare sector, but also for other pilot studies.

Why might urban tree canopy reduce dementia risk? A causal mediation analysis of 109,688 adults with 11 years of hospital and mortality records

Urban tree canopy is associated with lower dementia risk, but no mediation analysis has been attempted to reveal potential mechanisms. We examined 3,639 dementia diagnoses in 109,688 participants of the Sax Institute's 45 and Up Study. Adjusted models indicated ≥20% tree canopy lowered the odds of developing dementia by 14% over 11 years (Odds Ratio = 0.86, 95%CI = 0.79-0.93). Association between tree canopy and dementia was partially mediated by physical activity (4.5%) and absences of psychological distress (5.7%), social support (2.9%), sleep duration (2.3%) and diabetes (1.8%). Social loneliness and absence of heart disease or hypertension did not mediate the tree canopy-dementia association.

Sociodemographic structure and health care-related outcomes of community-dwelling dementia caregiving dyads: a latent class replication study

BACKGROUND

The identification of dyadic subgroups of individuals living with dementia and their informal caregivers can help to design effective tailored support. In a previous German study, we identified six dementia dyad subgroups by applying Latent Class Analysis (LCA). Results showed sociodemographic heterogeneity as well as differences in health care outcomes (i.e., quality of life, health status, caregiver burden) between subgroups. The objective of this study is to determine if the dyad subgroups from the previous analysis can be replicated in a similar but distinct Dutch sample.

METHODS

A LCA 3-step procedure was applied to baseline data from the COMPAS study, a prospective cohort study. LCA is a statistical approach used to identify heterogeneous subgroups within populations based on their pattern of answers on a set of categorical variables. Data comprises 509 community-living individuals with predominantly mild to moderate dementia and their informal caregivers. A narrative analysis was used to compare latent class structures of the original versus the replication study.

RESULTS

Six distinct dementia dyad subgroups were identified: A subgroup of "adult-child-parent relation with younger informal caregiver" (31.8%), a "couple with female informal caregiver of older age" group (23.1%), an "adult-child-parent relation with middle-aged informal caregiver" group (14.2%), a "couple with middle-aged female informal caregiver" group (12.4%), a "couple with older male informal caregiver" group (11.2%) and a "couple with middle-aged male informal caregiver" group (7.4%). Quality of life of individuals with dementia was rated better in couples than in adult-child-relationships. Worst health for caregivers was reported by subgroups with female informal caregivers living together with male individuals with dementia in couple relationships. A subgroup with older female informal caregivers in couple relationships report the most severe burden on physical and mental health. In both studies, a model with six subgroups fitted the data best. Although substantive similarities between the subgroups of both studies appeared, considerable differences are also evident.

CONCLUSION

This replication study confirmed the existence of informal dementia dyad subgroups. The observed differences between the subgroups provide useful contributions for a more tailored health care services for informal caregivers and individuals living with dementia. Furthermore, it underlines the relevance of dyadic perspectives. To facilitate replication studies and increase the validity of evidence, a standardization of collected data across studies would be beneficial.

Early life adversity as a risk factor for cognitive impairment and Alzheimer's disease

Neurological conditions, including cognitive impairment and Alzheimer's disease (AD), impose a huge burden on society, affecting millions of people globally. In addition to genetic factors, recent studies indicate that environmental and experiential factors may contribute to the pathogenesis of these diseases. Early life adversity (ELA) has a profound impact on brain function and health later in life. In rodent models, exposure to ELA results in specific cognitive deficits and aggravated AD pathology. Extensive concerns have been raised regarding the higher risk of developing cognitive impairments in people with a history of ELA. In this review, we scrutinize findings from human and animal studies focusing on the connection of ELA with cognitive impairment and AD. These discoveries suggest that ELA, especially at early postnatal stages, increases susceptibility to cognitive impairment and AD later in life. In terms of mechanisms, ELA could lead to dysregulation of the hypothalamus-pituitary-adrenal axis, altered gut microbiome, persistent inflammation, oligodendrocyte dysfunction, hypomyelination, and aberrant adult hippocampal neurogenesis. Crosstalks among these events may synergistically contribute to cognitive impairment later in life. Additionally, we discuss several interventions that may alleviate adverse consequences of ELA. Further investigation into this crucial area will help improve ELA management and reduce the burden of related neurological conditions.

The Role of Steroidomics in the Diagnosis of Alzheimer's Disease and Type 2 Diabetes Mellitus

Epidemiological studies suggest an association between Alzheimer's disease (AD) and type 2 diabetes mellitus (T2DM). This study aimed to investigate the pathophysiological markers of AD vs. T2DM for each sex separately and propose models that would distinguish control, AD, T2DM, and AD-T2DM comorbidity groups. AD and T2DM differed in levels of some circulating steroids (measured mostly by GC-MS) and in other observed characteristics, such as markers of obesity, glucose metabolism, and liver function tests. Regarding steroid metabolism, AD patients (both sexes) had significantly higher sex hormone binding globulin (SHBG), cortisol, and 17-hydroxy progesterone, and lower estradiol and 5α-androstane-3α,17β-diol, compared to T2DM patients. However, compared to healthy controls, changes in the steroid spectrum (especially increases in levels of steroids from the C21 group, including their 5α/β-reduced forms, androstenedione, etc.) were similar in patients with AD and patients with T2DM, though more expressed in diabetics. It can be assumed that many of these steroids are involved in counter-regulatory protective mechanisms that mitigate the development and progression of AD and T2DM. In conclusion, our results demonstrated the ability to effectively differentiate AD, T2DM, and controls in both men and women, distinguish the two pathologies from each other, and differentiate patients with AD and T2DM comorbidities.

Alterations to parvalbumin-expressing interneuron function and associated network oscillations in the hippocampal - medial prefrontal cortex circuit during natural sleep in AppNL-G-F/NL-G-F mice

In the early stages of Alzheimer's disease (AD), the accumulation of the peptide amyloid-β (Aβ) damages synapses and disrupts neuronal activity, leading to the disruption of neuronal oscillations associated with cognition. This is thought to be largely due to impairments in CNS synaptic inhibition, particularly via parvalbumin (PV)-expressing interneurons that are essential for generating several key oscillations. Research in this field has largely been conducted in mouse models that over-express humanised, mutated forms of AD-associated genes that produce exaggerated pathology. This has prompted the development and use of knock-in mouse lines that express these genes at an endogenous level, such as the App^{NL-G-F/NL-G-F} mouse model used in the present study. These mice appear to model the early stages of Aβ-induced network impairments, yet an in-depth characterisation of these impairments in currently lacking. Therefore, using 16 month-old App^{NL-G-F/NL-G-F} mice, we analysed neuronal oscillations found in the hippocampus and medial prefrontal cortex (mPFC) during awake behaviour, rapid eye movement (REM) and non-REM (NREM) sleep to assess the extent of network dysfunction. No alterations to gamma oscillations were found to occur in the hippocampus or mPFC during either awake behaviour, REM or NREM sleep. However, during NREM sleep an increase in the power of mPFC spindles and decrease in the power of hippocampal sharp-wave ripples was identified. The latter was accompanied by an increase in the synchronisation of PV-expressing interneuron activity, as measured using two-photon Ca²⁺ imaging, as well as a decrease in PV-expressing interneuron density. Furthermore, although changes were detected in local network function of mPFC and hippocampus, long-range communication between these regions appeared intact. Altogether, our results suggest that these NREM sleep-specific impairments represent the early stages of circuit breakdown in response to amyloidopathy.

Maintenance of mitochondrial homeostasis for Alzheimer's disease: Strategies and challenges

Alzheimer's disease (AD) is one of the most common neurodegenerative diseases, and its early onset is closely related to mitochondrial energy metabolism. The brain is only 2% of body weight, but consumes 20% of total energy needs. Mitochondria are responsible for providing energy in cells, and maintaining their homeostasis ensures an adequate supply of energy to the brain. Mitochondrial homeostasis is constituted by mitochondrial quantity and quality control, which is dynamically regulated by mitochondrial energy metabolism, mitochondrial dynamics and mitochondrial quality control. Impaired energy metabolism of brain cells occurs early in AD, and maintaining mitochondrial homeostasis is a promising therapeutic target in the future. We summarized the mechanism of mitochondrial homeostasis in AD, its influence on the pathogenesis of early AD, strategies for maintaining mitochondrial homeostasis, and mitochondrial targeting strategies. This review concludes with the authors' opinions on future research and development for mitochondrial homeostasis of early AD.

Entorhinal cortex epigenome-wide association study highlights four novel loci showing differential methylation in Alzheimer's disease

BACKGROUND

Studies on DNA methylation (DNAm) in Alzheimer's disease (AD) have recently highlighted several genomic loci showing association with disease onset and progression.

METHODS

Here, we conducted an epigenome-wide association study (EWAS) using DNAm profiles in entorhinal cortex (EC) from 149 AD patients and control brains and combined these with two previously published EC datasets by meta-analysis (total n = 337).

RESULTS

We identified 12 cytosine-phosphate-guanine (CpG) sites showing epigenome-wide significant association with either case-control status or Braak's tau-staging. Four of these CpGs, located in proximity to CNFN/LIPE, TENT5A, PALD1/PRF1, and DIRAS1, represent novel findings. Integrating DNAm levels with RNA sequencing-based mRNA expression data generated in the same individuals showed significant DNAm-mRNA correlations for 6 of the 12 significant CpGs. Lastly, by calculating rates of epigenetic age acceleration using two recently proposed "epigenetic clock" estimators we found a significant association with accelerated epigenetic aging in the brains of AD patients vs. controls.

CONCLUSION

In summary, our study represents the hitherto most comprehensive EWAS in AD using EC and highlights several novel differentially methylated loci with potential effects on gene expression.

Angiotensin-II stimulating vs. inhibiting antihypertensive drugs and the risk of Alzheimer's disease or related dementia in a large cohort of older patients with colorectal cancer

Background

Several previous studies showed that patients who received angiotensin II-stimulating antihypertensive medications had a lower incident dementia rate than those angiotensin II-inhibiting antihypertensive users, but no study has been conducted in long-term cancer survivors.

Objectives

To determine the risk of Alzheimer's disease (AD) and related dementia (ADRD) associated with the types of antihypertensive medications in a large cohort of survivors with colorectal cancer in 2007-2015 with follow-up from 2007 to 2016.

Methods

We identified 58,699 men and women with colorectal cancer aged 65 or older from the Surveillance, Epidemiology, and End Results (SEER)-Medicare linked database in 17 SEER areas in 2007-2015 with follow-up to 2016, who were free of any diagnosed ADRD at the baseline (within 12 months prior to and 12 months after the date of diagnosis for colorectal cancer). All patients who were defined as having hypertension by ICD diagnosis code or received antihypertensive drugs during this baseline 2-year period were classified into 6 groups based on whether they received angiotensin-II stimulating or inhibiting antihypertensive drugs.

Results

Crude cumulative incidence rates of AD and ADRD were similar between those who received angiotensin II-stimulating antihypertensive medications (4.3% and 21.7%) and those receiving angiotensin II-inhibiting antihypertensive medications (4.2% and 23.5%). As compared to patients who received angiotensin II-stimulating antihypertensive drugs, those who received angiotensin II-inhibiting antihypertensives were significantly more likely to develop AD (adjusted hazard ratio: 1.15, 95% CI: 1.01-1.32), vascular dementias (1.27, 1.06-1.53), and total ADRD (1.21, 1.14-1.28) after adjusting for potential confounders. These results remained similar after adjusting for medication adherence and considering death as a competing risk.

Conclusions

The risk of AD and ADRD in patients with hypertension who received angiotensin II-inhibiting antihypertensive medications was higher than in those receiving angiotensin II-stimulating antihypertensive drugs in patients with colorectal cancer.

In Vitro Simulated Gastrointestinal Digestion Stability of a Neuroprotective Octapeptide WCPFSRSF and Prediction of Potential Bioactive Peptides in Its Digestive Fragments by Multiple Bioinformatics Tools

WCPFSRSF, an octapeptide (Trp-Cys-Pro-Phe-Ser-Arg-Ser-Phe), has been reported to improve memory in mice, but its gastrointestinal stability is unclear. The objective of this study was to evaluate the gastrointestinal stability of peptide WCPFSRSF and explore the neuroprotective potential of its digestive fragments. Results showed that the content of WCPFSRSF after gastric and gastrointestinal digestion decreased to 71.64% and less than 1%, respectively. Furthermore, the antioxidant and neuroprotective ability of WCPFSRSF were also affected. Eleven and nine peptides were identified in its gastric and gastrointestinal digestive products, respectively. Multiple bioinformatics tools in combination with principal component analysis were employed to assess the physicochemical and structural properties of peptides. Novel peptides generated after gastrointestinal digestion could be classified into three groups: the first group had high bioactivity and bioavailability; the second group had high amphiphilicity, charge, and net hydrogen; and the third group had a long peptide chain. In addition, the representative peptides WCPF and SR showed neuroprotective ability.

A Phenome-Wide Association Study (PheWAS) of Late Onset Alzheimer Disease Genetic Risk in Children of European Ancestry at Middle Childhood: Results from the ABCD Study

Genetic risk for Late Onset Alzheimer Disease (AD) has been associated with lower cognition and smaller hippocampal volume in healthy young adults. However, whether these and other associations are present during childhood remains unclear. Using data from 5556 genomically-confirmed European ancestry youth who completed the baseline session of the ongoing the Adolescent Brain Cognitive DevelopmentSM Study (ABCD Study®), our phenome-wide association study estimating associations between four indices of genetic risk for late-onset AD (i.e., AD polygenic risk scores (PRS), APOE rs429358 genotype, AD PRS with the APOE region removed (ADPRS-APOE), and an interaction between ADPRS-APOE and APOE genotype) and 1687 psychosocial, behavioral, and neural phenotypes revealed no significant associations after correction for multiple testing (all ps > 0.0002; all pfdr > 0.07). These data suggest that AD genetic risk may not phenotypically manifest during middle-childhood or that effects are smaller than this sample is powered to detect.