Alzheimer's disease and vascular dementia in developing countries: prevalence, management, and risk factors

Cortical and subcortical gray matter abnormalities in mild cognitive impairment

Gray matter changes are thought to be closely related to cognitive decline in mild cognitive impairment (MCI) patients. The study aimed to explore cortical and subcortical structural alterations in MCI and their association with cognitive assessment. 24 MCI patients and 22 normal controls (NCs) were included. Voxel-based morphometry (VBM), vertex-based shape analysis and surface-based morphometry (SBM) analysis were applied to explore subcortical nuclei volume, shape and cortical morphology. Correlations between structural changes and cognition were explored using spearman correlation analysis. Support vector machine (SVM) classification evaluated MCI identification accuracy. MCI patients showed significant atrophy in the left thalamus, left hippocampus, left amygdala, right pallidum, right hippocampus, along with inward deformation in the left amygdala. SBM analysis revealed that MCI group exhibited shallower sulci depth in the left hemisphere and increased cortical gyrification index (GI) in the right frontal gyrus. Correlation analysis showed the positive correlation between right hippocampus volume and episodic memory, while negative correlation between the altered GI and memory performance in MCI group. SVM analysis demonstrated superior performance of sulci depth and GI derived from SBM in MCI identification. When combined with cortical and subcortical metrics, SVM achieved a peak accuracy of 89 % in distinguishing MCI from NC. The study reveals significant gray matter structural changes in MCI, suggesting their potential role in underlying functional differences and neural mechanisms behind memory impairment in MCI.

Challenges in evaluating cognitive impairment in diabetics in the Democratic Republic of the Congo

Dementia is a global public health issue, with 57.5 million people living with at least one type of dementia in 2019 worldwide, and projected to rise to 152 million by 2050.

Objective

We assessed the cognitive function in diabetic patients aged 60 or older in Bukavu city, in the eastern Republic of the Congo (DRC).

Methods

This case-control study involved 123 patients with established diabetes mellitus (DM) and 123 controls over 60-year-olds also with high rates of illiteracy. Cognitive function was assessed using the Swahili version of the Community Screening Instrument for Dementia (CSI-D).

Results

Foremost, our study revealed language-related differences between Swahili spoken in other eastern African countries such as Tanzania and Kenya, where the Swahili CSI-D is readily applied, compared to the Swahili spoken in Bukavu (DRC). Our results also showed that cognitive impairment was present in 18.7% of the total 246 participants. Remarkably, the prevalence rate of cognitive impairment was higher in the non-diabetic group (12.2 versus 25.2%; p=0.009). Participants aged 80 or older were more likely to present with cognitive impairment compared to those aged less than 80 (adjusted odds ratio - aOR=70.27; 95% confidence interval - 95%CI 3.94-125.15; p=0.004). We also found that patients living with DM for more than 20 years were three times more likely to be impaired compared to those who were recently diagnosed with DM (aOR=3.63; 95%CI 1.70-18.81; p=0.026).

Conclusion

This study revealed that cognitive impairment was relatively high in Bukavu city. It emphasizes the lack of effective tools to assess cognitive function. This requires, therefore, that research be adapted to the intellect and cultural experiences of the patients.

Poststroke seizures and epilepsy increase the risk of dementia among stroke survivors: A population-based study

OBJECTIVE

With global aging, the occurrence of stroke and associated outcomes like dementia are on the rise. Seizures and epilepsy are common poststroke complications and have a strong connection to subsequent dementia. This study examines the relationship between poststroke seizures (PSS) or poststroke epilepsy (PSE) and dementia using a national health care database.

METHODS

We conducted a retrospective study using data from the Taiwan National Health Insurance Research Database from 2009 to 2020. We identified acute stroke patients from 2010 to 2015, excluding those with pre-existing neurological conditions. Based on age, sex, stroke severity level, and the year of index stroke, patients with PSS or PSE were matched to those without. The main outcome was incident dementia.

RESULTS

This study included 62 968 patients with an average age of 63 years, with males accounting for 62.9%. Of them, 60.3% had ischemic strokes, and 39.7% had hemorrhagic strokes. After an average follow-up period of 5.2 years, dementia developed in 15.9% of patients who had PSS or PSE, as opposed to 8.4% of those without these conditions. A time-dependent Fine and Gray competing risk analysis showed that PSS and PSE were significantly associated with dementia across all stroke types. Subgroup analyses revealed significantly increased risk of dementia across all age groups (<50, 50-64, and ≥65 years), sexes, and various stroke severity levels. The link between PSS or PSE and dementia was particularly pronounced in men, with a less distinct correlation in women.

SIGNIFICANCE

The risk of incident dementia was higher in patients with PSS or PSE. The potential for therapeutic interventions for seizures and epilepsy to reduce poststroke dementia underscores the importance of seizure screening and treatment in stroke survivors.

Loneliness, cerebrovascular and Alzheimer's disease pathology, and cognition

INTRODUCTION

Loneliness has a rising public health impact, but research involving neuropathology and representative cohorts has been limited.

METHODS

Inverse odds of selection weights were generalized from the autopsy sample of Rush Alzheimer's Disease Center cohorts (N = 680; 89 ± 9 years old; 25% dementia) to the US-representative Health and Retirement Study (N = 8469; 76 ± 7 years old; 5% dementia) to extend external validity. Regressions tested cross-sectional associations between loneliness and (1) Alzheimer's disease (AD) and cerebrovascular pathology; (2) five cognitive domains; and (3) relationships between pathology and cognition, adjusting for depression.

RESULTS

In weighted models, greater loneliness was associated with microinfarcts, lower episodic and working memory in the absence of AD pathology, lower working memory in the absence of infarcts, a stronger association of infarcts with lower episodic memory, and a stronger association of microinfarcts with lower working and semantic memory.

DISCUSSION

Loneliness may relate to AD through multiple pathways involving cerebrovascular pathology and cognitive reserve.

HIGHLIGHTS

Loneliness was associated with worse cognition in five domains. Loneliness was associated with the presence of microinfarcts. Loneliness moderated cognition-neuropathology associations. Transportability methods can provide insight into selection bias.

Exploring the therapeutic implications of natural compounds modulating apoptosis in vascular dementia

Vascular dementia (VaD) is a prevalent form of dementia stemming from cerebrovascular disease, manifesting in memory impairment and executive dysfunction, thereby imposing a substantial societal burden. Unfortunately, no drugs have been approved for the treatment of VaD due to its intricate pathogenesis, and the development of innovative and efficacious medications is urgently needed. Apoptosis, a programmed cell death process crucial for eliminating damaged or unwanted cells within an organism, assumes pivotal roles in embryonic development and tissue homeostasis maintenance. An increasing body of evidence indicates that apoptosis may significantly influence the onset and progression of VaD, and numerous natural compounds have demonstrated significant therapeutic potential. Here, we discuss the molecular mechanisms underlying apoptosis and its correlation with VaD. We also provide a crucial reference for developing innovative pharmaceuticals by systematically reviewing the latest research progress concerning the neuroprotective effects of natural compounds on VaD by regulating apoptosis. Further high-quality clinical studies are imperative to firmly ascertain these natural compounds' clinical efficacy and safety profiles in the treatment of VaD.

Biomimetic engineering of a neuroinflammation-targeted MOF nanozyme scaffolded with photo-trigger released CO for the treatment of Alzheimer's disease

Alzheimer's disease (AD) is one of the most fatal and irreversible neurodegenerative diseases, which causes a huge emotional and financial burden on families and society. Despite the progress made with recent clinical use of inhibitors of acetylcholinesterase and amyloid-β (Aβ) antibodies, the curative effects of AD treatment remain unsatisfactory, which is probably due to the complexity of pathogenesis and the multiplicity of therapeutic targets. Thus, modulating complex pathological networks could be an alternative approach to treat AD. Here, a neutrophil membrane-coated MOF nanozyme (denoted as Neu-MOF/Fla) is biomimetically engineered to disturb the malignant Aβ deposition-inflammation cycle and ameliorate the pathological network for effective AD treatment. Neu-MOF/Fla could recognize the pathological inflammatory signals of AD, and deliver the photo-triggered anti-inflammatory CO and MOF based hydrolytic nanozymes to the lesion area of the brain in a spontaneous manner. Based on the in vitro and in vivo studies, Neu-MOF/Fla significantly suppresses neuroinflammation, mitigates the Aβ burden, beneficially modulates the pro-inflammatory microglial phenotypes and improves the cognitive defects of AD mice models. Our work presents a good example for developing biomimetic multifunctional nanotherapeutics against AD by means of amelioration of multiple symptoms and improvement of cognitive defects.

The role of GZMA as a target of cysteine and biomarker in Alzheimer's disease, pelvic organ prolapse, and tumor progression

Objective: This study aims to investigate how changes in peripheral blood metabolites in Alzheimer's Disease (AD) patients affect the development of Pelvic Organ Prolapse (POP) using a multi-omics approach. We specifically explore the interactions of signaling pathways, gene expression, and protein-metabolite interactions, with a focus on GZMA and cysteine in age-related diseases. Methods: This study utilized multi-omics analysis, including metabolomics and transcriptomics, to evaluate the perturbations in peripheral blood metabolites and their effect on POP in AD patients. Additionally, a comprehensive pan-cancer and immune infiltration analysis was performed on the core targets of AD combined with POP, exploring their potential roles in tumor progression and elucidating their pharmacological relevance to solid tumors. Results: We identified 47 differential metabolites linked to 9 significant signaling pathways, such as unsaturated fatty acid biosynthesis and amino acid metabolism. A thorough gene expression analysis revealed numerous differentially expressed genes (DEGs), with Gene Set Enrichment Analysis (GSEA) showing significant changes in gene profiles of AD and POP. Network topology analysis highlighted central nodes in the AD-POP co-expressed genes network. Functional analyses indicated involvement in critical biological processes and pathways. Molecular docking studies showed strong interactions between cysteine and proteins PTGS2 and GZMA, and molecular dynamics simulations confirmed the stability of these complexes. In vitro validation demonstrated that cysteine reduced ROS levels and protected cell viability. GZMA was widely expressed in various cancers, associated with immune cells, and correlated with patient survival prognosis. Conclusion: Multi-omics analysis revealed the role of peripheral blood metabolites in the molecular dynamics of AD and their interactions with POP. This study identified potential biomarkers and therapeutic targets, emphasizing the effectiveness of integrative approaches in treating AD and POP concurrently. The findings highlight the need for in-depth research on novel targets and biomarkers to advance therapeutic strategies.

Dysregulation of Ion Channels and Transporters and Blood-Brain Barrier Dysfunction in Alzheimer's Disease and Vascular Dementia

The blood-brain barrier (BBB) plays a critical role in maintaining ion and fluid homeostasis, essential for brain metabolism and neuronal function. Regulation of nutrient, water, and ion transport across the BBB is tightly controlled by specialized ion transporters and channels located within its unique cellular components. These dynamic transport processes not only influence the BBB's structure but also impact vital signaling mechanisms, essential for its optimal function. Disruption in ion, pH, and fluid balance at the BBB is associated with brain pathology and has been implicated in various neurological conditions, including stroke, epilepsy, trauma, and neurodegenerative diseases such as Alzheimer's disease (AD). However, knowledge gaps exist regarding the impact of ion transport dysregulation on BBB function in neurodegenerative dementias. Several factors contribute to this gap: the complex nature of these conditions, historical research focus on neuronal mechanisms and technical challenges in studying the ion transport mechanisms in in vivo models and the lack of efficient in vitro BBB dementia models. This review provides an overview of current research on the roles of ion transporters and channels at the BBB and poses specific research questions: 1) How are the expression and activity of key ion transporters altered in AD and vascular dementia (VaD); 2) Do these changes contribute to BBB dysfunction and disease progression; and 3) Can restoring ion transport function mitigate BBB dysfunction and improve clinical outcomes. Addressing these gaps will provide a greater insight into the vascular pathology of neurodegenerative disorders.

Comparative Performance of Five Cognitive Screening Tests in a Large Sample of Seniors

INTRODUCTION

Recent introductions of disease-modifying treatments for Alzheimer's disease have re-invigorated the cause of early dementia detection. Cognitive "paper and pencil" tests represent the bedrock of clinical assessment, because they are cheap, easy to perform, and do not require brain imaging or biological testing. Cognitive tests vary greatly in duration, complexity, sociolinguistic biases, probed cognitive domains, and their specificity and sensitivity of detecting cognitive impairment (CI). Consequently, an ecologically valid head-to-head comparison seems essential for evidence-based dementia screening.

METHOD

We compared five tests: Montreal cognitive assessment (MoCA), Alzheimer's disease assessment scale-cognitive subscale (ADAS), Addenbrooke's cognitive examination (ACE-III), euro-coin handling test (Eurotest), and image identification test (Phototest) on a large sample of seniors (N = 456, 77.9 ± 8 years, 71% females). Their specificity and sensitivity were estimated in a novel way by contrasting each test's outcome to the majority outcome across the remaining tests (comparative specificity and sensitivity calculation [CSSC]). This obviates the need for an a priori gold standard such as a clinically clear-cut sample of dementia/MCI/controls. We posit that the CSSC results in a more ecologically valid estimation of clinical performance while precluding biases resulting from different dementia/MCI diagnostic criteria and the proficiency in detecting these conditions.

RESULTS

There exists a stark trade-off between behavioral test specificity and sensitivity. The test with the highest specificity had the lowest sensitivity, and vice versa. The comparative specificities and sensitivities were, respectively: Phototest (97%, 47%), Eurotest (94%, 55%), ADAS (90%, 68%), ACE-III (72%, 77%), MoCA (55%, 95%).

CONCLUSION

Assuming a CI prevalence of 10%, the shortest (∼3 min) and the simplest instrument, the Phototest, was shown to have the best overall performance (accuracy 92%, PPV 66%, NPV 94%).

Assessment of dementia knowledge in Indian speech-language pathology students

OBJECTIVES

Speech-language pathologists (SLPs) have a crucial role in assisting individuals with dementia due to the communication and swallowing challenges associated with the disease. As the number of dementia cases rises in India at an increasing rate, investigating the level of dementia knowledge of SLP students can offer insight into the preparedness of the healthcare system to meet this emerging demand.

METHOD

A cross-sectional survey was conducted on SLP students pursuing their final year undergraduate, postgraduate and doctoral degrees from four universities across India. Dementia knowledge was assessed using the Dementia Knowledge Assessment Scale (DKAS) and information about previous dementia exposure (both formal and informal) was collected. The collected data were analysed using quantitative methods.

RESULTS

A total of 220 students (64.70% response rate) completed the survey. Overall dementia knowledge was inadequate with an average score of 22.08 ± 10.06. Previous dementia exposure among the students was also found to be low and did not affect dementia knowledge scores.

DISCUSSION

Despite the fundamental role SLPs play in the care of individuals with dementia, the lack of knowledge in this area emphasizes the need for enhancing dementia training programs through educational curricula and clinical placements.

The relationship between major depressive disorder and dementia: A bidirectional two-sample Mendelian randomization study

BACKGROUND

Major depressive disorder (MDD) and dementia psychiatric and neurological diseases that are clinically widespread, but whether there is a causal link between them is still unclear. In this study, bidirectional two-sample Mendelian randomization (MR) was used to investigate the potential causal relationship between MDD and dementia via a genome-wide association study (GWAS) database, containing samples from the European population.

METHOD

We collected data on MDD and common clinical dementia subtypes from GWAS, including Alzheimer's disease (AD), frontotemporal dementia (FTD), dementia with Lewy bodies (DLB), Parkinson's disease with dementia (PDD), and vascular dementia (VaD). A series of bidirectional two-sample MR studies and correlation sensitivity analysis were carried out.

RESULTS

In the study of the effect of MDD on dementia subtypes, no causal relationship was found between MDD and dementia subtypes other than VaD, inverse variance weighted (IVW) method: odds ratio (OR), 2.131; 95 % confidence interval (CI), 1.249-3.639, P = 0.006; MDD-AD: OR, 1.000; 95 % CI, 0.999-1.001, P = 0.537; MDD-FTD: OR, 1.476; 95 % CI, 0.471-4.627, P = 0.505; MDD-PDD: OR, 0.592; 95 % CI, 0.204-1.718, P = 0.335; MR-Egger method: MDD-DLB: OR, 0.582; 95 % CI, 0.021-15.962, P = 0.751. In reverse MR analyses, no dementia subtype was found to be a risk factor for MDD.

LIMITATIONS

The results of this study may not be generalizable to non-European populations.

CONCLUSION

MDD was identified as a potential risk factor for VaD, but no dementia subtype was found to be a risk factor for MDD. These results suggest a new avenue for the prevention of VaD.

Multisensory Fusion Training and 7, 8-Dihydroxyflavone Improve Amyloid-β-Induced Cognitive Impairment, Anxiety, and Depression-Like Behavior in Mice Through Multiple Mechanisms

Background

There is growing interest in the role of physical activity in patients with of Alzheimer's disease (AD), particularly regarding its impact of cognitive function, gut microbiota, metabolites, and neurotrophic factors.

Objective

To investigate the impact of multisensory fusion training (MSFT) combined with 7, 8-dihydroxyflavone (DHF) on the behavioral characteristics, protein expression, microbiome, and serum metabolome using the AD model in mice induced with amyloid-β (Aβ).

Methods

We assessed cognitive ability, anxiety-like and depression-like behaviors in Aβ mice using behavioral measures. Western blotting was employed to detect the expression of relevant proteins. The 16S rRNA gene sequencing and metabolomics were used to analyze changes in the intestinal microbial composition and serum metabolic profile, respectively, of Aβ mice.

Results

The behavioral outcomes indicated that a 4-week intervention combining DHF and MSFT yielded remarkable improvements in cognitive function and reduced anxiety and depression-like behaviors in Aβ mice. In the hippocampus of Aβ mice, the combined intervention increased the levels of BDNF, VGF, PSD-95, Nrf2, p-GSK3β and p-CREB proteins. Analyses of sequence and metabolomic data revealed that Bacteroides and Ruminococcaceae were remarkably more abundant following the combined intervention, influencing the expression of specific metabolites directly linked to the maintenance of neuronal and neurobehavioral functions. These metabolites play a crucial role in vital processes, such as amino acid metabolism, lipid metabolism, and neurotransmitter metabolism in mice.

Conclusion

Our study highlighted that MSFT combined with DHF improves cognitive impairment, anxiety, and depression-like behavior in Aβ mice through multiple mechanisms, and further validated the correlation between the gut microbiome and serum metabolome. These findings open up a promising avenue for future investigations into potential treatment strategies for AD.

A novel prosthesis presentation test to screen for cognitive and functional decline

OBJECTIVES AND BACKGROUND

To validate a novel screening test for cognitive and functional decline in older patients rehabilitated with complete removable dental prostheses (CRDPs).

MATERIALS AND METHODS

Edentate old in-patients rehabilitated with CRDPs were included in this study. Participants were requested to remove their prostheses before their intraoral examinations. The prostheses were then presented in an inverted orientation. Participants had to correct the orientation of the prostheses and insert them in the appropriate jaws. The test was repeated after the intraoral exam. Appropriate statistical models were used (⍺ = .05) to associate the test results with the participants' mini-mental state examination (MMSE) score, functional independence measure (FIM), age and sex.

RESULTS

Among the 86 participants (mean-age: 85.4 ± 6.4 years; mean MMSE: 19.8 ± 5.5; mean FIM: 77.9 ± 20.8), 21 (24.4%) failed to correctly insert the prosthesis. The prosthesis presentation test (PPT) was associated with the FIM but not the MMSE. Regression models further confirmed an association with age (P = .043), but not sex. Additional analyses revealed the PPT test is associated with the FIM's cognitive sub-sets of memory, problem solving and social interaction.

CONCLUSION

The PPT is a novel, simple and quick screening tool that can help detect functional difficulties in older people. It can easily be performed during an oral examination. Future studies are needed to determine whether the PPT can be used to detect deficits in executive function, as a complement to the MMSE and also as a first assessment of a patient's ability to manage dentures independently.

Comprehensive Analysis of Dementia Types and Risk Factors: A Study From a Tertiary Care Center in India

Background and objective Dementia is a prevalent clinical syndrome characterized by memory impairment and cognitive dysfunction. Its global burden is expected to rise significantly, particularly in low- and middle-income countries. Understanding the spectrum of dementia types and associated risk factors is crucial for effective management. This study aims to elucidate the demographic profiles, clinical types, and risk factors of newly diagnosed dementia cases at a tertiary care hospital in India. Methods and materials A cross-sectional, hospital-based observational study was conducted on 81 patients at the Department of Medicine, Dr. D. Y. Patil Medical College, Hospital, and Research Centre, Pimpri, Pune, from February 2022 to January 2024. Ethical approval was obtained, and written consent was obtained from participants. Clinical diagnosis was based on the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-V) criteria, supported by cognitive assessment tools and laboratory/radiological investigations. Inclusion criteria encompassed individuals aged 18 years or older, presenting with clinical symptoms suggestive of dementia, having a Mini-Mental State Examination (MMSE) score of less than 24 and Montreal Cognitive Assessment (MoCA) score of less than 25, according to DSM-V criteria for dementia. Exclusion criteria included individuals with a history of head trauma or those below 18 years of age. Results Of the 81 participants, the majority (74.1%) were over 60 years old, with females comprising 59.3% of the sample. Alzheimer's disease was the most prevalent dementia subtype (34.5%), followed by vascular dementia (19.7%) and mixed dementia (13.5%). Other causes included Lewy body dementia (2.46%), Parkinson's dementia (4.9%), frontotemporal dementia (4.9%), and Creutzfeldt-Jakob disease (1.2%). Reversible causes accounted for a significant proportion of cases: alcohol-associated dementia (6.1%), hypothyroid-associated dementia (3.7%), HIV-associated dementia (2.46%), herpes simplex dementia (1.2%), neurosyphilis-associated dementia (1.2%), and normal pressure hydrocephalus (NPH)-associated dementia (2.4%). Analysis of risk factors revealed distinct patterns among different dementia types, emphasizing the role of cardiovascular and metabolic health. Conclusion This study provides insights into the demographic profiles, clinical types, and dementia risk factors in India. Addressing causes and managing cardiovascular/metabolic health is crucial for dementia prevention and management. Comprehensive care strategies and ongoing research efforts are essential for improving dementia outcomes and enhancing the quality of life for affected individuals and their families.

The prevalence and risk factors study of cognitive impairment: Analysis of the elderly population of Han nationality in Hunan province, China

OBJECTIVE

A large number of studies have found that the prevalence of cognitive impairment varies in different regions. However, data on cognitive impairment in the Chinese population is still lacking. The goal of this study was to assess the prevalence of cognitive impairment among the elderly in a region of China and explore the associated risk factors.

METHODS

We performed a population-based cross-sectional survey from April to June 2022. Residents come from three villages and six urban communities in the county-level city of Liuyang in southern China (N = 3233) and the coverage rate of our study population reached 73%. Participants were assessed with a series of clinical examinations and neuropsychological measures. A total of 2598 participants were selected after filtering out those under 60 years old or with incomplete data. Patients with cognitive impairment included those with mild cognitive impairment (MCI) or dementia who met standard diagnostic criteria.

RESULTS

The prevalence of cognitive impairment, MCI, and dementia among participants aged 60 years and older were 21.48% (95% CI, 19.90-23.10), 15.70% (95% CI, 14.30-17.10), and 5.77 (95% CI, 4.90-6.70), respectively. And residents in villagers were more likely to have cognitive impairment than in urban communities (p < 0.001). Age growth and education level were independent influencing factors for cognitive impairment in all populations (p < 0.001). For lifestyles factors, both smoking and drinking reduced the risk of cognitive impairment (p < 0.05), but when further quantified, the link disappeared. Moreover, having cerebrovascular disease and severe vision impairment were risk factors (p < 0.05).

CONCLUSION

A representative prevalence of cognitive impairment, MCI, and dementia was found in the elderly Han Chinese population in Southern China. And we further explored the role of known risk factors, particularly in physical activity, smoking, and alcohol consumption.

Diverticular disease and risk of dementia: a Danish population-based cohort study

BACKGROUND AND AIM

Patients with diverticular disease (DD) have ongoing chronic inflammation associated with changes in the gut microbiome, which might contribute to the development of dementia.

METHODS

Using Danish medical and administrative registries from 1980 to 2013, we conducted a nationwide population-based cohort study including all DD patients and a matched (5:1) general population comparison cohort without DD. A nested case-control analysis was then conducted using a risk set sampling, matching four DD controls without dementia to each DD patient with dementia. Clinical severity was categorized as uncomplicated DD (outpatient), conservatively treated DD (inpatient), and surgically treated DD.

RESULTS

149 527 DD patients and 747 635 general population comparators were identified. The 30-year cumulative incidence of dementia among DD patients and general population comparators were 12.4 (95% confidence interval [CI] 12.1-12.7) and 13.73% (95% CI 13.6-13.9), respectively. This corresponded to a 30-year hazard ratio (HR) of 1.10 (95% CI 1.1-1.1). The highest HRs were found in the conservatively treated DD group (1.15 95% CI 1.1-1.2) and the group with young onset of DD (1.52 95% CI 1.2-2.0). In the nested case-control analysis, we identified 8875 dementia cases and 35 491 matched controls. The adjusted odds ratio (OR) for conservatively treated DD was increased (1.08, 95% CI; 1.0-1.2) compared to the reference of uncomplicated DD.

CONCLUSIONS

We observed a slight increased risk of dementia in patients with young onset DD and conservatively treated DD. Findings suggest an association between disease duration, perhaps reflecting the duration of gut inflammation, and the risk of developing dementia.

Epigenetics and the neurodegenerative process

Neurological diseases are multifactorial, genetic and environmental. Environmental factors such as diet, physical activity and emotional state are epigenetic factors. Environmental markers are responsible for epigenetic modifications. The effect of epigenetic changes is increased inflammation of the nervous system and neuronal damage. In recent years, it has been shown that epigenetic changes may cause an increased risk of neurological disorders but, currently, the relationship between epigenetic modifications and neurodegeneration remains unclear. This review summarizes current knowledge about neurological disorders caused by epigenetic changes in diseases such as Alzheimer's disease, Parkinson's disease, stroke and epilepsy. Advances in epigenetic techniques may be key to understanding the epigenetics of central changes in neurological diseases.

Pathways to care for people with dementia in India: An exploratory study using case vignettes

BACKGROUND

Limited evidence exists on how people living with dementia and their family/unpaid carers navigate care and support in India.

AIM

This study used case vignettes to illustrate likely pathways to care for dementia, from receiving a diagnosis to long-term support, in India and to highlight gaps and challenges associated with current care provision for persons living with dementia.

METHODS

As part of the Strengthening Responses to Dementia in Developing Countries (STRiDE) project, and to contribute to an analysis of dementia care policies and systems in India, case vignettes were used to illustrate the diverse situations that people with dementia and their families may experience when seeking care in the Indian context. Eight hypothetical, but realistic cases of people with dementia were created by a multi-disciplinary team with experience in dementia care in India, to map out the likely care journeys of each case.

RESULTS

Investigating eight diverse care trajectories of people living with dementia highlighted important patterns relevant to the Indian context. We identified delays in dementia diagnosis to be attributed to low awareness of dementia among the general public and medical professionals in addition to a critical shortage of specialist services involved in facilitating dementia diagnosis. Post-diagnosis, support was recognized as limited and associated with considerable out-of-pocket (OOP) costs. Families primarily provide long-term care for people with dementia till end of life.

CONCLUSIONS AND RECOMMENDATIONS

Several steps need to be taken in order to improve dementia care in India. Increasing dementia awareness among both medical professionals and general public is essential. Shortages in dementia specialists can be addressed in part through appropriate task shifting. Lastly, more research is needed to develop evidence-based community interventions to support informal care provision for persons with dementia in India.

The Role of NRF2 in Cerebrovascular Protection: Implications for Vascular Cognitive Impairment and Dementia (VCID)

Vascular cognitive impairment and dementia (VCID) represents a broad spectrum of cognitive decline secondary to cerebral vascular aging and injury. It is the second most common type of dementia, and the prevalence continues to increase. Nuclear factor erythroid 2-related factor 2 (NRF2) is enriched in the cerebral vasculature and has diverse roles in metabolic balance, mitochondrial stabilization, redox balance, and anti-inflammation. In this review, we first briefly introduce cerebrovascular aging in VCID and the NRF2 pathway. We then extensively discuss the effects of NRF2 activation in cerebrovascular components such as endothelial cells, vascular smooth muscle cells, pericytes, and perivascular macrophages. Finally, we summarize the clinical potential of NRF2 activators in VCID.

Microglial ApoD-induced NLRC4 inflammasome activation promotes Alzheimer's disease progression

BACKGROUND

Alzheimer's disease (AD) is a progressive neurodegenerative disease with no effective therapies. It is well known that chronic neuroinflammation plays a critical role in the onset and progression of AD. Well-balanced neuronal-microglial interactions are essential for brain functions. However, determining the role of microglia-the primary immune cells in the brain-in neuroinflammation in AD and the associated molecular basis has been challenging.

METHODS

Inflammatory factors in the sera of AD patients were detected and their association with microglia activation was analyzed. The mechanism for microglial inflammation was investigated. IL6 and TNF-α were found to be significantly increased in the AD stage.

RESULTS

Our analysis revealed that microglia were extensively activated in AD cerebra, releasing sufficient amounts of cytokines to impair the neural stem cells (NSCs) function. Moreover, the ApoD-induced NLRC4 inflammasome was activated in microglia, which gave rise to the proinflammatory phenotype. Targeting the microglial ApoD promoted NSC self-renewal and inhibited neuron apoptosis. These findings demonstrate the critical role of ApoD in microglial inflammasome activation, and for the first time reveal that microglia-induced inflammation suppresses neuronal proliferation.

CONCLUSION

Our studies establish the cellular basis for microglia activation in AD progression and shed light on cellular interactions important for AD treatment.

Clinical evidence of hyperbaric oxygen therapy for Alzheimer's disease: a systematic review and meta-analysis of randomized controlled trials

Objective

To evaluate the potential benefits of hyperbaric oxygen intervention on people with Alzheimer's disease (AD) based on the existing randomized controlled trials (RCTs).

Methods

A systematic search was conducted in nine databases until November 17, 2023, for RCTs assessing the effect of hyperbaric oxygen intervention for AD. The primary outcomes included Mini-Mental State Examination (MMSE), Alzheimer's Disease Assessment Scale-Cognitive (ADAS-Cog), activities of daily living (ADL), and adverse events. All results were shown in forest plots, and sensitivity analysis was adopted to further verify the robustness of the pooled results.

Results

A total of 11 RCTs recruiting 847 participants were included in this meta-analysis. Based on the pooled evidence, hyperbaric oxygen could remarkably ameliorate MMSE [MD = 3.08, 95%CI (2.56, 3.61), p < 0.00001], ADAS-Cog [MD = -4.53, 95%CI (-5.05, -4.00), p < 0.00001], ADL [MD = 10.12, 95%CI (4.46, 15.79), p = 0.0005], MDA levels [SMD = -2.83, 95%CI (-5.27, -0.38), p = 0.02], SOD levels [SMD = 2.12, 95%CI (1.10, 3.15), p < 0.0001], IL-1-β levels [SMD = -1.00, 95%CI (-1.48, -0.53), p < 0.0001], and TGF-β1 levels [MD = 4.87, 95%CI (3.98, 5.76), p < 0.00001] without adverse events [OR = 1.17, 95%CI (0.68, 2.03), p = 0.58] for people with AD. The pooled results were robust after checking by sensitivity analysis.

Conclusion

These evidences suggest that hyperbaric oxygen is an effective and safe intervention for the treatment of AD. Further studies with more rigorous design will help to fully evaluate the clinical value of hyperbaric oxygen on cognition function in people with AD.

Systematic review registration

https://www.crd.york.ac.uk, identifier CRD42023483726.

Recognizing Alzheimer's disease from perspective of oligodendrocytes: Phenomena or pathogenesis?

BACKGROUND

Accumulation of amyloid beta, tau hyperphosphorylation, and microglia activation are the three highly acknowledged pathological factors of Alzheimer's disease (AD). However, oligodendrocytes (OLs) were also widely investigated in the pathogenesis and treatment for AD.

AIMS

We aimed to update the regulatory targets of the differentiation and maturation of OLs, and emphasized the key role of OLs in the occurrence and treatment of AD.

METHODS

This review first concluded the targets of OL differentiation and maturation with AD pathogenesis, and then advanced the key role of OLs in the pathogenesis of AD based on both clinic and basic experiments. Later, we extensively discussed the possible application of the current progress in the diagnosis and treatment of this complex disease.

RESULTS

Molecules involving in OLs' differentiation or maturation, including various transcriptional factors, cholesterol homeostasis regulators, and microRNAs could also participate in the pathogenesis of AD. Clinical data point towards the impairment of OLs in AD patients. Basic research further supports the central role of OLs in the regulation of AD pathologies. Additionally, classic drugs, including donepezil, edaravone, fluoxetine, and clemastine demonstrate their potential in remedying OL impairment in AD models, and new therapeutics from the perspective of OLs is constantly being developed.

CONCLUSIONS

We believe that OL dysfunction is one important pathogenesis of AD. Factors regulating OLs might be biomarkers for early diagnosis and agents stimulating OLs warrant the development of anti-AD drugs.

Associations between vascular health, brain stiffness and global cognitive function

Vascular brain injury results in loss of structural and functional connectivity and leads to cognitive impairment. Its various manifestations, including microinfarcts, microhaemorrhages and white matter hyperintensities, result in microstructural tissue integrity loss and secondary neurodegeneration. Among these, tissue microstructural alteration is a relatively early event compared with atrophy along the aging and neurodegeneration continuum. Understanding its association with cognition may provide the opportunity to further elucidate the relationship between vascular health and clinical outcomes. Magnetic resonance elastography offers a non-invasive approach to evaluate tissue mechanical properties, providing a window into the microstructural integrity of the brain. This retrospective study evaluated brain stiffness as a potential biomarker for vascular brain injury and its role in mediating the impact of vascular dysfunction on cognitive impairment. Seventy-five participants from the Mayo Clinic Study of Aging underwent brain imaging using a 3T MR imager with a spin-echo echo-planar imaging sequence for magnetic resonance elastography and T1- and T2-weighted pulse sequences. This study evaluated the effects of vascular biomarkers (white matter hyperintensities and cardiometabolic condition score) on brain stiffness using voxelwise analysis. Partial correlation analysis explored associations between brain stiffness, white matter hyperintensities, cardiometabolic condition and global cognition. Mediation analysis determined the role of stiffness in mediating the relationship between vascular biomarkers and cognitive performance. Statistical significance was set at P-values < 0.05. Diagnostic accuracy of magnetic resonance elastography stiffness for white matter hyperintensities and cardiometabolic condition was evaluated using receiver operator characteristic curves. Voxelwise linear regression analysis indicated white matter hyperintensities negatively correlate with brain stiffness, specifically in periventricular regions with high white matter hyperintensity levels. A negative association between cardiovascular risk factors and stiffness was also observed across the brain. No significant patterns of stiffness changes were associated with amyloid load. Global stiffness (µ) negatively correlated with both white matter hyperintensities and cardiometabolic condition when all other covariables including amyloid load were controlled. The positive correlation between white matter hyperintensities and cardiometabolic condition weakened and became statistically insignificant when controlling for other covariables. Brain stiffness and global cognition were positively correlated, maintaining statistical significance after adjusting for all covariables. These findings suggest mechanical alterations are associated with cognitive dysfunction and vascular brain injury. Brain stiffness significantly mediated the indirect effects of white matter hyperintensities and cardiometabolic condition on global cognition. Local cerebrovascular diseases (assessed by white matter hyperintensities) and systemic vascular risk factors (assessed by cardiometabolic condition) impact brain stiffness with spatially and statistically distinct effects. Global brain stiffness is a significant mediator between vascular disease measures and cognitive function, highlighting the value of magnetic resonance elastography-based mechanical assessments in understanding this relationship.

Biomarker Changes during 20 Years Preceding Alzheimer's Disease

BACKGROUND

Biomarker changes that occur in the period between normal cognition and the diagnosis of sporadic Alzheimer's disease have not been extensively investigated in longitudinal studies.

METHODS

We conducted a multicenter, nested case-control study of Alzheimer's disease biomarkers in cognitively normal participants who were enrolled in the China Cognition and Aging Study from January 2000 through December 2020. A subgroup of these participants underwent testing of cerebrospinal fluid (CSF), cognitive assessments, and brain imaging at 2-year-to-3-year intervals. A total of 648 participants in whom Alzheimer's disease developed were matched with 648 participants who had normal cognition, and the temporal trajectories of CSF biochemical marker concentrations, cognitive testing, and imaging were analyzed in the two groups.

RESULTS

The median follow-up was 19.9 years (interquartile range, 19.5 to 20.2). CSF and imaging biomarkers in the Alzheimer's disease group diverged from those in the cognitively normal group at the following estimated number of years before diagnosis: amyloid-beta (Aβ)42, 18 years; the ratio of Aβ42 to Aβ40, 14 years; phosphorylated tau 181, 11 years; total tau, 10 years; neurofilament light chain, 9 years; hippocampal volume, 8 years; and cognitive decline, 6 years. As cognitive impairment progressed, the changes in CSF biomarker levels in the Alzheimer's disease group initially accelerated and then slowed.

CONCLUSIONS

In this study involving Chinese participants during the 20 years preceding clinical diagnosis of sporadic Alzheimer's disease, we observed the time courses of CSF biomarkers, the times before diagnosis at which they diverged from the biomarkers from a matched group of participants who remained cognitively normal, and the temporal order in which the biomarkers became abnormal. (Funded by the Key Project of the National Natural Science Foundation of China and others; ClinicalTrials.gov number, NCT03653156.).

How Does Tobacco Use Affect the Cognition of Older Adults? A Propensity Score Matching Analysis Based on a Large-Scale Survey

INTRODUCTION

Tobacco is a well-established risk factor for cancer, but its association with other morbidities needs consideration. The low-income and middle-income countries (LMICs) with unprecedented demographic transformation lack evidence on tobacco use and its impact on cognitive health.

AIMS AND METHODS

Using a propensity score matching approach, we utilized data from the Longitudinal Ageing Study of India. Study employed 1:1 nearest neighbor matching with the replacement methodology. We estimated the odds of the poor cognitive score and tobacco use among older adults based on five different models for ever tobacco user, former tobacco user, current tobacco user, current smokers, and current smokeless tobacco users with reference to never tobacco users.

RESULTS

The estimated average treatment effect for the treated and the untreated group has shown a higher likelihood of cognitive decline among ever (OR -0.26; 95%CI -0.43 to -0.09), current (OR -0.28; 95%CI -0.45 to -0.10), and former (OR -0.53; 95%CI -0.87 to -0.19) tobacco users compared to never tobacco users. The finding further suggests the odds of lower cognitive scores among older adults who were smokers (OR -0.53; 95%CI -0.87 to -0.19) and smokeless tobacco users (OR -0.22; 95%CI -0.43 to -0.01) as compared to never tobacco users.

CONCLUSIONS

Interventions designed to prevent the incidence of cognitive impairment should focus on limiting the use of tobacco. Strategies under the tobacco-free generation initiative should be amplified in order to prevent future generations from productivity loss, premature ageing and to promote healthy aging.

IMPLICATIONS

Evidence of a definitive association between tobacco consumption and cognition among older adults is sporadic in LMICs. Though tobacco is a risk factor for various diseases including cancer, the extent of its impact on cognitive health among the older population is limited. This study contributes to the existing literature by highlighting poor cognitive outcomes among older adults who smoke tobacco and/or consume smokeless tobacco as compared to never-tobacco users. Our findings emphasize the need to accelerate programmes related to tobacco-free generation in LMICs to reach a higher quality of life and healthy aging in pursuit of achieving the sustainable development goal of "good health and well-being."

Pattern of cognitive impairment among community-dwelling elderly in Egypt and its relation to socioeconomic status

BACKGROUND

Cognitive decline is one of the aging health problems that strongly affects daily functioning and quality of life of older adults and threatens their independence. The aim of this study was to assess the prevalence and pattern of cognitive impairment (CI) among community-dwelling elderly in Egypt and the contribution of socioeconomic status to inequality in cognitive impairment.

METHODS

A cross-sectional study involved 470 community-dwelling elderly aged 60 years or older living in Kafr El-Sheikh Governorate, Egypt. Subjects were recruited from home visits, geriatric clubs, and outpatient clinics. The Montreal Cognitive Assessment tools (MoCA & MoCA-B) were used to assess the prevalence of cognitive impairment, Hachinski ischemic score (HIS) to investigate the type of cognitive impairment, Ain Shams Cognitive Assessment (ASCA) tool to assess the pattern of specific cognitive domain affection, and an Egyptian socioeconomic status (SES) scale to classify the SES of the study participants.

RESULTS

The prevalence of cognitive impairment was 50.2% distributed as 37.7% for mild cognitive impairment (MCI) and 12.5% for dementia. The most common type of cognitive impairment was the degenerative type (47.9%). Pattern of specific domain affection among cognitively impaired subjects ranged from 94% for visuospatial function to 12.7% for abstraction. Cognitive impairment was significantly higher with increasing age, female sex, marital status (single or widow), low education, higher number of comorbidities, and positive family history of cognitive impairment (p < 0.001). Also, cognitive impairment was concentrated mainly among participants with low socioeconomic score (p < 0.001).

CONCLUSION

In Egypt, cognitive impairment is significantly prevalent and concentrated among those who are in low socioeconomic status. Patients with mild CI were more than those with dementia, and the most common type of CI was the degenerative type. Increasing educational level of low SES population and improving their access to healthcare services are highly recommended to improve the inequity of cognitive impairment.

Potential role of APOE ɛ4 allele as a modifier for the association of BDNF Val66Met polymorphisms and cognitive impairment in community-dwelling older adults

Objective

To determine whether the brain-derived neurotrophic factor (BDNF) Val66Met polymorphism is associated with cognitive impairment (CI) in community-dwelling Chinese older adults, and to investigate whether this relationship is modified by the Apolipoprotein E (APOE) ɛ4 allele.

Methods

The study is a secondary analysis of 703 participants aged ≥60 years randomly enrolled from the Beijing Longitudinal Study of Aging II prospective cohort. The education-adjusted Mini-Mental State Examination and the Clinical Dementia Rating Scale were used to measure the cognitive performance of the subjects. The main effects and interactions (additive and multiplicative) of the BDNF Met and the APOE ε4 alleles on CI were estimated by logistic regression models.

Results

In total, 84 out of 703 older adults aged ≥60 years old had CI. No significant difference was observed in the risk of CI between participants with the BDNF Met allele and that of subjects without the BDNF Met allele (p = 0.213; p = 0.164). Individuals carrying both the BDNF Met and APOE ε4 alleles had an almost 1.5-fold increased odds of CI compared with carriers of the BDNF Met allele but without the APOE ε4 allele. The additive association indicated a positive interaction of both BDNF Met and APOE ε4 alleles with wide CIs (p = 0.021; p = 0.018).

Conclusion

The results suggest that the APOE ε4 allele may be a potential modifier for the association of the BDNF Val66Met polymorphism with CI in community-dwelling older adults.

Prevalence of sarcopenia in Africa: a systematic review and meta-analysis of observational studies

BACKGROUND

Existing literature suggests that sarcopenia is a highly prevalent condition in older people. However, most studies to date reporting data on its prevalence have been mainly carried out in Western countries, while data on sarcopenia in Africa is scarce. With this systematic review and meta-analysis, we aimed to determine the prevalence of sarcopenia in African countries and to explore potential factors that could explain higher or lower prevalence of this condition in Africa.

METHODS

Major databases for studies reporting data on sarcopenia in African countries were searched from inception to June 2023. We conducted a meta-analysis of the prevalence [and 95% confidence intervals (95% CIs)] of sarcopenia in Africa, applying a random effect model. Several sensitivity and meta-regression analyses were run.

RESULTS

Among 147 articles initially screened, six articles (with seven cohorts) including a total of 10,656 participants were included. Mean age of participants was 66.9 years, and the majority were female (58.1%). The weighted prevalence of sarcopenia in the selected countries of Africa was 25.72% (95%CI: 18.90-32.55). This outcome was characterized by a high heterogeneity (I2 = 99%) and by publication bias. Among the factors investigated, sarcopenia was lower when assessed using only one anthropometric measure, or in South Africa.

CONCLUSION

Sarcopenia is a prevalent condition in Africa and thus research regarding this topic is a public health priority. Future studies that cover African countries for which data are not available and using standardized criteria are needed.

Association of Glycemic Variability With Imaging Markers of Vascular Burden, β-Amyloid, Brain Atrophy, and Cognitive Impairment

BACKGROUND AND OBJECTIVE

We aimed to investigate the association between glycemic variability (GV) and neuroimaging markers of white matter hyperintensities (WMH), beta-amyloid (Aβ), brain atrophy, and cognitive impairment.

METHODS

This was a retrospective cohort study that included participants without dementia from a memory clinic. They all had Aβ PET, brain MRI, and standardized neuropsychological tests and had fasting glucose (FG) levels tested more than twice during the study period. We defined GV as the intraindividual visit-to-visit variability in FG levels. Multivariable linear regression and logistic regression were used to identify whether GV was associated with the presence of severe WMH and Aβ uptake with DM, mean FG levels, age, sex, hypertension, and presence of APOE4 allele as covariates. Mediation analyses were used to investigate the mediating effect of WMH and Aβ uptake on the relationship between GV and brain atrophy and cognition.

RESULTS

Among the 688 participants, the mean age was 72.2 years, and the proportion of female participants was 51.9%. Increase in GV was predictive of the presence of severe WMH (coefficient [95% CI] 1.032 [1.012-1.054]; p = 0.002) and increased Aβ uptake (1.005 [1.001-1.008]; p = 0.007). Both WMH and increased Aβ uptake partially mediated the relationship between GV and frontal-executive dysfunction (GV → WMH → frontal-executive; direct effect, -0.319 [-0.557 to -0.080]; indirect effect, -0.050 [-0.091 to -0.008]) and memory dysfunction (GV → Aβ → memory; direct effect, -0.182 [-0.338 to -0.026]; indirect effect, -0.067 [-0.119 to -0.015]), respectively. In addition, increased Aβ uptake completely mediated the relationship between GV and hippocampal volume (indirect effect, -1.091 [-2.078 to -0.103]) and partially mediated the relationship between GV and parietal thickness (direct effect, -0.00101 [-0.00185 to -0.00016]; indirect effect, -0.00016 [-0.00032 to -0.000002]).

DISCUSSION

Our findings suggest that increased GV is related to vascular and Alzheimer risk factors and neurodegenerative markers, which in turn leads to subsequent cognitive impairment. Furthermore, GV can be considered a potentially modifiable risk factor for dementia prevention.

Beyond loss: An essay about presence and sparkling moments based on observations from life coexisting with a person living with dementia

This is an essay based on a story with observations, about present and sparkling moments from everyday life coexisting with a mother living with dementia. The story is used to begin philosophical underpinnings reflecting on 'how it could be otherwise'. Dementia deploys brutal existential experiences such as cognitive deterioration, decline in mental functioning and often hurtful social judgements. The person living with dementia goes through transformation and changes of self. Cognitive decline progressively disrupts the foundations upon which social connectedness is built, often creating a profound sense of insecurity. The challenge for carers and healthcare professionals is therefore to find ways of clarifying a concept of agency. It will be worthwhile developing the ability of attuning into 'what is there' arising from every corner of the care situation. Understanding and practicing this can strengthen existence and the experience of connectedness and meaning, empowering the person with dementia. It is important to find ways, relational moves, in which carers and healthcare professionals can embed the creativity appearing in mundane everyday situations filled with surplus of meaning, sharing mental landscapes (and embodied relational understanding) with the person living with dementia - seizing and sharing aesthetic moments (verbal and nonverbal) being present together. We argue that carers and healthcare professionals may find this understanding of care useful. This implies looking into a phenomenological-hermeneutic perspective developing competences as well as practical wisdom understanding and being aware of the creative and innovative possibilities (often preverbal and unnoticed small things) in everyday life of what we, inspired by psychoanalyst Daniel Stern, call sparkling moments of meeting, creating experience with the other that is personally undergone and lived through in the present.

Current perspectives on prevention of vascular cognitive impairment and promotion of vascular brain health

INTRODUCTION

The true global burden of vascular cognitive impairment (VCI) is unknown. Reducing risk factors for stroke and cardiovascular disease would inevitably curtail VCI.

AREAS COVERED

The authors review current diagnosis, epidemiology, and risk factors for VCI. VCI increases in older age and by inheritance of known genetic traits. They emphasize modifiable risk factors identified by the 2020 Lancet Dementia Commission. The most profound risks for VCI also include lower education, cardiometabolic factors, and compromised cognitive reserve. Finally, they discuss pharmacological and non-pharmacological interventions.

EXPERT OPINION

By virtue of the high frequencies of stroke and cardiovascular disease the global prevalence of VCI is expectedly higher than prevalent neurodegenerative disorders causing dementia. Since ~ 90% of the global burden of stroke can be attributed to modifiable risk factors, a formidable opportunity arises to reduce the burden of not only stroke but VCI outcomes including progression from mild to the major in form of vascular dementia. Strict control of vascular risk factors and secondary prevention of cerebrovascular disease via pharmacological interventions will impact on burden of VCI. Non-pharmacological measures by adopting healthy diets and encouraging physical and cognitive activities and urging multidomain approaches are important for prevention of VCI and preservation of vascular brain health.

Multimodal Gamma Stimulation Improves Activity but not Memory in Aged Tgf344-AD Rats

BACKGROUND

Multimodal sensory gamma stimulation is a treatment approach for Alzheimers disease that has been shown to improve pathology and memory in transgenic mouse models of Alzheimer's. Because rats are closer to humans in evolution, we tested the hypothesis that the transgenic rat line bearing human APP and PS1, line TgF344-AD, would be a good supplemental candidate to test the efficacy of this treatment. Current therapy approaches under investigation seek to utilize the immune response to minimize or degrade the accumulation of β-amyloid plaque load in mouse models designed to overexpress Aβ. However, many of these models lack some of the hallmarks of Alzheimer's disease, such as hyperphosphorylated tau and neuronal cell loss. The TgF344-AD transgenic rat model is a good candidate to bridge the gap between mouse models and clinical efficacy in humans.

OBJECTIVE

The objective of this study was to use multimodal gamma stimulation at light and auditory modalities simultaneously to test whether this enhances memory performance as measured by the object location task and the spontaneous alternation task.

METHODS

In our study, we designed and built a low-cost, easy-to-construct multimodal light and sound gamma stimulator. Our gamma stimulation device was built using an Arduino microcontroller, which drives lights and a speaker at the gamma frequency. We have included in this paper our device's parts, hardware design, and software architecture for easy reproducibility. We then performed an experiment to test the effect of multimodal gamma stimulation on the cognitive performance of fourteen-month-old TgF344-AD rats. Rats were randomly assigned to either an experimental group that received gamma stimulation or a control group that did not. Performance in a Novel Object Location (NOL) task and spontaneous alternation task was evaluated in both groups before and after the treatment.

RESULTS

Multimodal gamma stimulation did not improve memory compared to unstimulated TgF344-AD rats. However, the gamma-stimulated rats did spend significantly more time exploring objects in the novel location task than the unstimulated rats. In the spontaneous alternation task, gamma-stimulated rats exhibited significantly greater exploratory activity than unstimulated controls.

CONCLUSION

Multimodal gamma stimulation did not enhance memory performance in the object location task or the spontaneous alternation task. However, in both tasks, the treatment group had improved measures of exploratory activity relative to the untreated group. We conclude that several limitations could have contributed to this mixed effect, including aging complications, different animal models, or light cycle effects.

Activation of glutamatergic neurons in the somatosensory cortex promotes remyelination in ischemic vascular dementia

Chronic cerebral hypoperfusion can cause progressive demyelination as well as ischemic vascular dementia, however no effective treatments are available. Here, based on magnetic resonance imaging studies of patients with white matter damage, we found that this damage is associated with disorganized cortical structure. In a mouse model, optogenetic activation of glutamatergic neurons in the somatosensory cortex significantly promoted oligodendrocyte progenitor cell (OPC) proliferation, remyelination in the corpus callosum, and recovery of cognitive ability after cerebral hypoperfusion. The therapeutic effect of such stimulation was restricted to the upper layers of the cortex, but also spanned a wide time window after ischemia. Mechanistically, enhancement of glutamatergic neuron-OPC functional synaptic connections is required to achieve the protection effect of activating cortical glutamatergic neurons. Additionally, skin stroking, an easier method to translate into clinical practice, activated the somatosensory cortex, thereby promoting OPC proliferation, remyelination and cognitive recovery following cerebral hypoperfusion. In summary, we demonstrated that activating glutamatergic neurons in the somatosensory cortex promotes the proliferation of OPCs and remyelination to recover cognitive function after chronic cerebral hypoperfusion. It should be noted that this activation may provide new approaches for treating ischemic vascular dementia via the precise regulation of glutamatergic neuron-OPC circuits.

Oral Health as a Risk Factor for Alzheimer Disease

In patients with Alzheimer's disease pathophysiological changes of the brain that initiate the onset of Alzheimer's disease include accumulation of amyloid-β plaques and phosphorylation of tau-tangles. A rather recently considered risk factor for the onset of Alzheimer's disease is poor oral health. The aim of this systematic review of the literature was to assess the potential association(s) of oral health as a risk factor for the onset of Alzheimer's disease. After a systematic search of Pubmed, Embase and Web of Science. A total of 1962 studies were assessed, of which 17 studies demonstrated possible associations between oral health diseases and Alzheimer's disease. 4 theories could be distinguished that describe the possible links between oral health and the development or onset of Alzheimer's disease; 1) role of pathogens, 2) role of inflammatory mediators, 3) role of APOE alleles and 4) role of Aβ peptide. The main common denominator of all the theories is the neuroinflammation due to poor oral health. Yet, there is insufficient evidence to prove a link due to the diversity of the designs used and the quality of the study design of the included studies. Therefore, further research is needed to find causal links between oral health and neuroinflammation that possibly can lead to the onset of Alzheimer's disease with the future intention to prevent cognitive decline by better dental care.

Synthesis and molecular docking simulation of new benzimidazole-thiazole hybrids as cholinesterase inhibitors

Dementia is a cognitive disturbance that is generally correlated with central nervous system diseases, especially Alzheimer's disease. The limited number of medications available is insufficient to improve the lifestyle of the patients suffering from this disease. Thus, new benzimidazole-thiazole hybrids (3-10) were designed and synthesized as acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory agents. The in vitro evaluation displayed that the derivatives 4b, 4d, 5b, 6a, 7a, and 8b demonstrated dual inhibitory efficiency against both AChE with IC50 ranging from 4.55 to 8.62 µM and BChE with IC50 ranging from 3.50 to 8.32 µM. By analyzing the Lineweaver-Burk plot, an uncompetitive form of inhibition was determined for the highly active compound 4d, revealing its inhibition type. The human telomerase reverse transcriptase-immortalized retinal pigment epithelial cell line was used to ensure the safety of the most potent cholinesterase inhibitors. Furthermore, compounds 4b, 4d, 5b, 6a, 7a, and 8b were evaluated for their neuroprotective and antioxidant properties, as well as their ability to suppress COX-2. The results demonstrated that compounds 4d, 5b, and 8b presented significant neuroprotection efficiency against H2 O2 -induced damage in SH-SY5Y cells with % cell viability of 67.42 ± 7.90%, 62.51 ± 6.71%, and 72.61 ± 8.10%, respectively, while the tested candidates did not reveal significant antioxidant activity. Otherwise, compounds 4b, 6a, 7a, and 8b displayed outstanding COX-2 inhibition effects with IC50 ranging from 0.050 to 0.080 μM relative to celecoxib (IC50  = 0.050 µM). In addition, molecular docking was carried out for the potent benzimidazole-thiazole hybrids with the active sites of both AChE (PDB ID: 4EY7) and BChE (PDB code: 1P0P). The tested candidates fit well in the active sites of both portions, with docking scores ranging from -8.65 to -6.64 kcal/mol (for AChE) and -8.71 to -7.73 kcal/mol (for BChE). In silico results show that the synthesized benzimidazole-thiazole hybrids have good physicochemical and pharmacokinetic properties with no Lipinski rule violations. The preceding results exhibited that compound 4d could be used as a new template for developing more significant cholinesterase inhibitors in the future.

Impact of Optimism on Cognitive Performance of People Living in Rural Area: Findings From a 20-Year Study in US Adults

Objectives: Mid- or early-late-life cognitive function is an indicator for developing late-life dementia. However, it is still unclear whether rural/urban living contexts provide cognitive benefits across adulthood. Further, higher optimism serves as a general protective factor for many health outcomes. The present study examines associations between rurality/urbanicity, optimism, and change in mid/late-life cognitive functions over time. Methods: Data were from waves 1 to 3 (1995-2015) of the Midlife in the United States (MIDUS) study (N = 2,507). Structural equation models examine whether long-term rural living across both waves (1-2) or intermittent rural living at one wave is associated with better cognitive function over 20 years, compared to no rural living, while controlling for prior cognitive function and covariates (baseline socio-demographics, health, and functional status). Additionally, we assessed if optimism mediates the above associations. Results: After controlling for covariates, long-term rural living (waves 1-2) was indirectly (through less optimism) associated with significantly lower levels of cognitive executive function and episodic memory in wave 3. Conclusions: While long-term rural living and cognitive outcomes have no direct association for MIDUS middle-aged and older adults, mediating roles of optimism in these associations were evident. Future investigations could examine mechanisms that underlie these risk/protective factors on late-life cognition.

GLP-1/GIP Agonist as an Intriguing and Ultimate Remedy for Combating Alzheimer's Disease through its Supporting DPP4 Inhibitors: A Review

BACKGROUND

Alzheimer's disease (AD) is a widespread neurological illness in the elderly, which impacted about 50 million people globally in 2020. Type 2 diabetes has been identified as a risk factor. Insulin and incretins are substances that have various impacts on neurodegenerative processes. Preclinical research has shown that GLP-1 receptor agonists decrease neuroinflammation, tau phosphorylation, amyloid deposition, synaptic function, and memory formation. Phase 2 and 3 studies are now occurring in Alzheimer's disease populations. In this article, we present a detailed assessment of the therapeutic potential of GLP-1 analogues and DPP4 inhibitors in Alzheimer's disease.

AIM

This study aimed to gain insight into how GLP-1 analogues and associated antagonists of DPP4 safeguard against AD.

METHODS

This study uses terms from search engines, such as Scopus, PubMed, and Google Scholar, to explore the role, function, and treatment options of the GLP-1 analogue for AD.

RESULTS

The review suggested that GLP-1 analogues may be useful for treating AD because they have been linked to anti-inflammatory, neurotrophic, and neuroprotective characteristics. Throughout this review, we discuss the underlying causes of AD and how GLP signaling functions.

CONCLUSION

With a focus on AD, the molecular and pharmacological effects of a few GLP-1/GIP analogs, both synthetic and natural, as well as DPP4 inhibitors, have been mentioned, which are in the preclinical and clinical studies. This has been demonstrated to improve cognitive function in Alzheimer's patients.

The relationships between mastication and cognitive function: A systematic review and meta-analysis

Masticatory function such as chewing is expected to modify human cognitive function, and/or the possibility of improving cognitive function is also predicted. This systematic review investigated whether masticatory function affects cognitive function for older/young adults. Full articles written in English from January 2000 to April 2022 were collected using PubMed and Cochrane Library. Target outcomes were cognitive function test scores, cognitive processing speed (reaction time), and masticatory function. For each research question, two independent reviewers conducted the search and screening, data extraction, quality assessment, and risk of bias assessment. The reviewers resolved any disagreements by discussion. From 226 articles retrieved, 20 were included in this review. Older adults with lower scores on the cognitive function test had lower masticatory performance, lower chewing ability, chewing difficulty, and decreased number of teeth. An increased risk of cognitive impairment was found in older adults with masticatory dysfunction. For young adults, gum chewing significantly reduced the processing speed of cognitive tasks compared to no gum chewing. Although most of the evidence included had a low level of evidence and a high risk of bias because of the research designs, the results still suggest that mastication may be a factor in improving cognitive function.

Novel insights into molecular signatures and pathogenic cell populations shared by systemic lupus erythematosus and vascular dementia

Although vascular dementia (VD) and systemic lupus erythematosus (SLE) may share immune-mediated pathophysiologic processes, the underlying mechanisms are unclear. This study investigated shared gene signatures in SLE versus VD, as well as their potential molecular mechanisms. Bulk RNA sequencing (RNAseq) and single-cell or single-nucleus RNAseq (sc/snRNAseq) datasets from SLE blood samples and VD brain samples were obtained from Gene Expression Omnibus. The identification of genes associated with both SLE and VD was performed using the weighted gene co-expression network analysis (WGCNA) and machine learning algorithms. For the sc/snRNAseq data, an unbiased clustering pipeline based on Seurat and CellChat was used to determine the cellular landscape profile and examine intracellular communication, respectively. The results were subsequently validated using a mice model of SLE with cognitive dysfunction (female MRL/lpr mice). WGCNA and machine learning identified C1QA, LY96, CD163, and MS4A4A as key genes for SLE and VD. sc/snRNAseq analyses revealed that CD163 and MS4A4A were upregulated in mononuclear phagocytes (MPs) from SLE and VD samples and were associated with monocyte-macrophage differentiation. Intriguingly, LGALS9-associated molecular pathway, as the only signaling pathway common between SLE and VD via CellChat analysis, exhibited significant upregulation in cortical microglia of MRL/lpr mice. Our analyses identified C1QA, LY96, CD163, and MS4A4A as potential biomarkers for SLE and VD. Moreover, the upregulation of CD163/MS4A4A and activation of LGALS9 signaling in MPs may contribute to the pathogenesis of VD with SLE. These findings offer novel insight into the mechanisms underlying VD in SLE patients.

Metallomics analysis of metal exposure and cognitive function in older adults: A combined epidemiological and bioinformatics study

Dementia is a significant cause of elderly disability and Alzheimer's disease (AD) is the most prevalent form of dementia. As an early stage of AD, the mechanism related to mild cognitive impairment (MCI) and heavy metals is still unclear. This study utilized a cross-sectional design and enrolled 514 older adults in Bejing, China. Cognitive function was assessed by the Mini-Mental State Examination (MMSE) and fourteen blood metals were measured by inductively coupled plasma mass spectrometry (ICP-MS). In the adjusted single-metal models, we observed that copper [Cu, β (95% CI): 3.73 (-6.42, -1.03)] and lead [Pb, β (95% CI): 0.79 (-1.26, -0.32)] demonstrated negative associations with cognitive function, while selenium [Se, β (95% CI): 2.97 (1.23, 4.70)] was beneficial to cognition. Our findings were robust in secondary analysis using multi-metal models, which included generalized linear models (GLM), Bayesian kernel machine regression (BKMR), and quantile g-computation (qgcomp). Moreover, the toxic metal mixture (Cu and Pb) exhibited a significant negative association with MMSE scores and the inclusion of Se in the metal mixture attenuated the neurotoxicity of Cu-Pb mixture. The in silico analysis was used to examine the potential molecular mechanisms (genes, biological processes, pathways, and illnesses) of interaction among metal mixtures. We identified 20 cognition-related genes that are associated with both Cu-Pb and Se. Among these genes, eight (APOE, APP, BAX, BDNF, CASP3, HMOX1, TF, and TPP1) exhibited opposite effects on protein activity, mRNA expression, or protein expression in response to Se and Cu/Pb exposure, which could be the key genes accounting for the anti-neurotoxic effects of Se. Our findings support that Se can attenuate the neurotoxicity of exposure to single Cu or Pb, and Cu-Pb mixture. More research is needed to confirm our findings and gain knowledge about the molecular mechanisms of combined metal exposure on cognitive function.

Transferrin-Conjugated Melittin-Loaded L-Arginine-Coated Iron Oxide Nanoparticles for Mitigating Beta-Amyloid Pathology of the 5XFAD Mouse Brain

Alzheimer's disease (AD) is one of the most prevalent neurodegenerative diseases and a major contributor to dementia. Although the cause of this condition has been identified long ago as aberrant aggregations of amyloid and tau proteins, effective therapies for it remain elusive. The complexities of drug development for AD treatment are often compounded by the impermeable blood-brain barrier and low-yield brain delivery. In addition, the use of high drug concentrations to overcome this challenge may entail side effects. To address these challenges and enhance the precision of delivery into brain regions affected by amyloid aggregation, we proposed a transferrin-conjugated nanoparticle-based drug delivery system. The transferrin-conjugated melittin-loaded L-arginine-coated iron oxide nanoparticles (Tf-MeLioNs) developed in this study successfully mitigated melittin-induced cytotoxicity and hemolysis in the cell culture system. In the 5XFAD mouse brain, Tf-MeLioNs remarkably reduced amyloid plaque accumulation, particularly in the hippocampus. This study suggested Tf-LioNs as a potential drug delivery platform and Tf-MeLioNs as a candidate for therapeutic drug targeting of amyloid plaques in AD. These findings provide a foundation for further exploration and advancement in AD therapeutics.

A blood-based, metabolite and demographic characteristic markers panel for the diagnosis of Alzheimer's disease

Aims: This work was designed to provide early diagnosis strategies for Alzheimer's disease (AD) based on the identification of blood metabolic biomarkers. Patients & methods: A total of 90 subjects aged 60 years or older were included in this study; 45 patients were assigned to the case group and control group, respectively. A total of 31 target metabolites were quantitatively analyzed by parallel reaction monitoring between the two groups. Results & conclusion: Three metabolites were screened out, including cystine, serine and alanine/sarcosine. Logistic regression and random forest analysis were used to establish AD diagnosis models, and the model combining metabolic biomarkers and demographic variables had higher detection efficiency (area under the curve = 0.869). A combination diagnostic model to provide a scientific reference for early screening and diagnosis of AD was constructed.

RAGE acted as a new anti-inflammatory target for Icariin's treatment against vascular dementia based on network pharmacology-directed verification

Vascular dementia (VaD) ranks as the second most prevalent form of dementia and poses a considerable global health challenge. Icariin has been recognized for its robust neuroprotective effects in combating VaD. Nonetheless, the underlying mechanisms have not been fully elucidated. An integrated approach involving network pharmacology, molecular docking, and molecular dynamics simulations (MDS) was employed to systematically investigate the potential pharmacological actions of Icariin in counteracting VaD. The AGE/RAGE pathway was identified as a promising anti-inflammatory pathway. A chronic cerebral hypoperfusion mouse model was utilized to establish VaD. Both Icariin and FP S-ZM1 (a RAGE inhibitor) were administered through oral gavage and intraperitoneal injection, respectively. The Morris water maze (MWZ) was used to evaluate cognitive functions. Moreover, immunofluorescence, RT-qP CR, and Western blot analyses were carried out to evaluate the effects of FP S-ZM1 on neuroinflammation. Network analysis identified 14 crucial targets and highlighted the AGE-RAGE signaling cascade in diabetic complications as the foremost KEGG pathway with potential anti-neuroinflammatory property. MDS results suggested a stable binding of the RAGE-Icariin complex. Remarkably, Icariin was found to effectively mitigate cognitive deficits in VaD mice, which was correlated with the upregulation of the P I3K/AKT pathway and downregulation of the JNK/cJUN signaling cascade. Critically, co-administration of FP S-ZM1 enhanced Icariin's ameliorative effects on cognitive deficits, owing to bolstered anti-neuroinflammatory action. This study unveils the potential of Icariin in alleviating cognitive dysfunction and neuroinflammation in VaD, which may be attributed to the modulation of the AGE/RAGE pathway.Communicated by Ramaswamy H. Sarma.

The Development of a Pilot App Targeting Short-Term and Prospective Memory in People Diagnosed with Dementia

BACKGROUND

According to the World Health Organization, people suffering from dementia exhibit a serious decline in various cognitive domains and especially in memory.

AIMS

This study aims to create a pilot computer app to enhance short-term memory and prospective memory in individuals with dementia using errorless learning based on their individualized needs.

METHODS

Fifteen dementia patients and matched controls, matched for age, sex, and education, were selected. Their daily routines were analyzed, and cognitive abilities were assessed using the MoCA test. Considering the participants' illness severity and daily needs, the pilot app was designed to aid in remembering daily tasks (taking medication and meals), object locations, and familiar faces and names.

RESULTS

An improvement in patients' short-term and prospective memory throughout the training sessions, but not in overall cognitive functioning was observed. A statistically significant difference between patients and healthy controls was indicated in their ability to retain information relevant to them in their short-term memory, or to remember to act in the future following schedules organized at present (p < 0.001).

CONCLUSION

This app appears beneficial for training dementia patients and healthy individuals in addressing memory challenges.

RECOMMENDATION

While the pilot app showed promise, further research with larger samples is recommended.

Insulin-degrading enzyme: Roles and pathways in ameliorating cognitive impairment associated with Alzheimer's disease and diabetes

Accumulation of amyloid-β in the central nervous system is a common feature of Alzheimer's disease (AD) and diabetes-related cognitive impairment. Since the insulin-degrading enzyme (IDE) can break down amyloid-β plaques, there is considerable interest in using this enzyme to treat both neurological disorders. In this review, we have summarized the pre-clinical and clinical research on the potential application of IDE for the improvement of cognitive impairment. Furthermore, we have presented an overview of the main pathways that can be targeted to mitigate the progression of AD and the cognitive impairment caused by diabetes.

One-Year Survival after Cardiac Surgery in Frail Older People-Social Support Matters: A Prospective Cohort Study

There are increasing rates of cardiac surgery in the elderly. Frailty, depression, and social vulnerability are frequently present in older people, and should be considered while assessing risk and providing treatment options. We aimed to analyse the impact of clinically relevant variables on survival at one year, and identify areas of future intervention. We performed a prospective cohort study at a University Hospital, with a sample of 309 elective cardiac surgery patients 65 years old and over. Their socio-demographic and clinical variables were collected. Frailty prevalence was 61.3%, while depression was absent in the majority of patients. Mortality was 1.6% and 7.8% at 30 days and 12 months, respectively. After Kaplan-Meier analysis, severe frailty (p = 0.003), severe depression (p = 0.027), pneumonia until 30 days (p = 0.014), and re-operation until 12 months (p = 0.003) significantly reduced survival, while social support increased survival (p = 0.004). In the adjusted multivariable Cox regression model, EuroSCORE II (HR = 1.27 [95% CI 1.069-1.499] p = 0.006), pneumonia until 30 days (HR = 4.19 [95% CI 1.169-15.034] p = 0.028), re-intervention until 12 months (HR = 3.14 [95% CI 1.091-9.056] p = 0.034), and social support (HR = 0.24 [95% CI 0.079-0.727] p = 0.012) explained time until death. Regular screening for social support, depression, and frailty adds relevant information regarding risk stratification, perioperative interventions, and decision-making in older people considered for cardiac surgery.

World-wide variations in tests of cognition and activities of daily living in participants of six international randomized controlled trials

Background

Better understanding of worldwide variation in simple tests of cognition and global function in older adults would aid the delivery and interpretation of multi-national studies of the prevention of dementia and functional decline.

Method

In six RCTs that measured cognition with the mini-mental state examination (MMSE), Montreal cognitive assessment (MoCA), and activities of daily living (ADL) with the Standardised Assessment of Everyday Global Activities (SAGEA), we estimated average scores by global region with multilevel mixed-effects models. We estimated the proportion of participants with cognitive or functional impairment with previously defined thresholds (MMSE≤24 or MoCA≤25, SAGEA≥7), and with a country-standardised z-score threshold of cognitive or functional score of ≤-1.

Results

In 91,396 participants (mean age 66.6 years [SD 7.8], 31% females) from seven world regions, all global regions differed significantly in estimated cognitive function (z-score differences 0.11-0.45, p<0.001) after accounting for individual-level factors, centre and study. In different regions, the proportion of trial participants with MMSE≤24 or MoCA≤25 ranged from 23-36%; the proportion below a country-standardised z-score threshold of ≤1 ranged from 10-14%. The differences in prevalence of impaired IADL (SAGEA≥7) ranged from 2-6% and by country-standardised thresholds from 3-6%.

Conclusions

Accounting for country-level factors reduced large differences between world regions in estimates of cognitive impairment. Measures of IADL were less variable across world regions, and could be used to better estimate dementia prevalence in large studies.

Diabetes incidence in Austria: The role of famines on diabetes and related NCDs

Undernutrition in early life associates with increased risk for type 2 diabetes in later life. Whether similar associations hold for other diseases remains unclear. We aim to quantify how perinatal exposure to famines relates to the risk of becoming incident with type 2 diabetes in later life. Using population-wide medical claims data for Austrians aged >50y, yearly diabetes incidence was measured in an epidemiological progression model. We find incidence rates that increase from 2013 to 2017 and observe two famine-related birth cohorts of 5,887 patients with incidence rate increases for diabetes of up to 78% for males and 59% for females compared to cohorts born two years earlier. These cohorts show increased risks for multiple other diagnoses as well. Public health efforts to decrease diabetes must not only focus on lifestyle factors but also emphasize the importance of reproductive health and adequate nutrition during pregnancy and early postnatal life.

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.