Evidence-based prevention of Alzheimer's disease: systematic review and meta-analysis of 243 observational prospective studies and 153 randomised controlled trials

Plasma levels of adipokines and insulin are associated with markers of brain atrophy and cognitive decline in the spectrum of Alzheimer's Disease

The discovery that metabolic alterations often coexist with neurodegenerative conditions has sparked interest in the examination of metabolic regulatory factors as potential modulators of brain health. Here, we examined the role of adipokines (leptin, adiponectin, resistin, and IL6) and insulin on different markers of brain atrophy in participants on the spectrum of Alzheimer's Disease. We included 566 participants from the Alzheimer's Disease Neuroimaging Initiative (ADNI) dataset with 1063 follow-up time points (average follow-up: one year); and examined the association between metabolic regulatory factors and volumetric MRI values, white matter hyperintensities, and measures of cognitive impairment. Higher leptin, resistin, IL6, and insulin were associated with markers of cerebral atrophy, such as lower total brain volume, or higher ventricular volume. Higher leptin and resistin were also associated with greater impairment in daily life activities. Higher adiponectin was associated with lower ventricle volume. There was no association between adipokines or insulin with white matter hyperintensities. Our findings indicate a co-occurrence between alterations in metabolic regulatory factors and in brain volume along the preclinical to clinical spectrum of Alzheimer's Disease. These results suggest that strategies aimed at promoting metabolic health may positively impact brain health.

Associations of sugar intake, high-sugar dietary pattern, and the risk of dementia: a prospective cohort study of 210,832 participants

BACKGROUND

Limited evidence demonstrated the potential relationship between dietary sugar intake and dementia. This association demands further clarification in a large-scale population.

METHODS

A total of 210,832 participants from the UK Biobank cohort were included in this prospective cohort study. Absolute and relative sugar intake and high-sugar dietary scores were utilized to reflect dietary sugar intake. Absolute sugar intake was identified by the Oxford WebQ in the UK Biobank. Relative sugar intake was calculated by dividing the absolute sugar intake by total diet energy. High-sugar dietary pattern was identified using the method of reduced rank regression. Cox proportional hazards regression analyses and restricted cubic splines were performed to examine the longitudinal associations between dietary sugar intake and all-cause dementia and its main subtype, Alzheimer's disease. Explorative mediation analyses were conducted to explore underlying mechanisms.

RESULTS

Increased absolute sugar intake (g/day) was significantly associated with a higher risk of all-cause dementia (HR = 1.003, [95%CI: 1.002-1.004], p < 0.001) and Alzheimer's disease (1.002, [1.001-1.004], 0.005). Relative sugar intake (%g/kJ/day) also demonstrated significant associations with all-cause dementia (1.317, [1.173-1.480], p < 0.001) and Alzheimer's disease (1.249, [1.041-1.500], 0.017), while the high-sugar dietary score was only significantly associated with a higher risk of all-cause dementia (1.090, [1.045-1.136], p < 0.001). In addition, both sugar intake and high-sugar dietary score demonstrated significant non-linear relationships with all-cause dementia and Alzheimer's disease (all p values for non-linearity < 0.05).

CONCLUSIONS

Our study provided evidence that excessive sugar intake was associated with dementia. Controlling the excess consumption of dietary sugar may be of great public health implications for preventing dementia.

Essential New Complexity-Based Themes for Patient-Centered Diagnosis and Treatment of Dementia and Predementia in Older People: Multimorbidity and Multilevel Phenomenology

Dementia is a highly prevalent condition with devastating clinical and socioeconomic sequela. It is expected to triple in prevalence by 2050. No treatment is currently known to be effective. Symptomatic late-onset dementia and predementia (SLODP) affects 95% of patients with the syndrome. In contrast to trials of pharmacological prevention, no treatment is suggested to remediate or cure these symptomatic patients. SLODP but not young onset dementia is intensely associated with multimorbidity (MUM), including brain-perturbating conditions (BPCs). Recent studies showed that MUM/BPCs have a major role in the pathogenesis of SLODP. Fortunately, most MUM/BPCs are medically treatable, and thus, their treatment may modify and improve SLODP, relieving suffering and reducing its clinical and socioeconomic threats. Regrettably, the complex system features of SLODP impede the diagnosis and treatment of the potentially remediable conditions (PRCs) associated with them, mainly due to failure of pattern recognition and a flawed diagnostic workup. We suggest incorporating two SLODP-specific conceptual themes into the diagnostic workup: MUM/BPC and multilevel phenomenological themes. By doing so, we were able to improve the diagnostic accuracy of SLODP components and optimize detecting and favorably treating PRCs. These revolutionary concepts and their implications for remediability and other parameters are discussed in the paper.

The role of Immune cells in Alzheimer's disease: a bidirectional Mendelian randomization study

Background

Alzheimer's disease (AD) is a leading cause of dementia, characterized by the accumulation of amyloid-beta (Aβ) and hyperphosphorylated tau proteins, leading to neuroinflammation and neuronal damage. The role of the immune system in AD pathogenesis is increasingly recognized, prompting an exploration of the causal relationship between immune cells and AD by using Mendelian randomization (MR) approaches.

Methods

Utilizing genome-wide association study (GWAS) data from European cohorts, we conducted an MR study to investigate the causal links between immune cell phenotypes and AD. We selected single nucleotide polymorphisms (SNPs) associated with immune cell traits at a genome-wide significance threshold and applied various MR methods, including MR Egger, Weighted median, and inverse variance weighted analysis, to assess the causality between 731 immune phenotypes and AD.

Results

Our MR analysis identified 15 immune cell types with significant causal relationships to AD pathogenesis. Notably, the absolute count of CD28-CD4-CD8- T cells and the expression of HLA DR on B cells were linked to a protective effect against AD, while 13 other immune phenotypes were identified as contributing to the risk factors for the disease. The causal effects of AD on immunophenotypic traits are predominantly negative, implying that AD may impair the functionality of immune cells. Validation through independent datasets, such as FinnGen and GCST90027158, confirmed the causal association between six specific immune cells and AD.

Conclusion

This comprehensive MR study elucidates the intricate network of causal relationships between diverse immunophenotypic traits and AD, providing novel insights into the immunopathogenesis of AD. The findings suggest potential immunological targets that could be leveraged for early diagnosis, disease monitoring, and therapeutic intervention.

Charting Alzheimer's Disease and Dementia: Epidemiological Insights, Risk Factors and Prevention Pathways

Alzheimer's disease (AD), the most common cause of dementia, is a complex and multifactorial condition without cure at present. The latest treatments, based on anti-amyloid monoclonal antibodies, have only a modest effect in reducing the progression of cognitive decline in AD, whereas the possibility of preventing AD has become a crucial area of research. In fact, recent studies have observed a decrease in dementia incidence in developed regions such as the US and Europe. However, these trends have not been mirrored in non-Western countries (Japan or China), and the contributing factors of this reduction remain unclear. The Lancet Commission has delineated a constrained classification of 12 risk factors across different life stages. Nevertheless, the scientific literature has pointed to over 200 factors-including sociodemographic, medical, psychological, and sociocultural conditions-related to the development of dementia/AD. This narrative review aims to synthesize the risk/protective factors of dementia/AD. Essentially, we found that risk/protective factors vary between individuals and populations, complicating the creation of a unified prevention strategy. Moreover, dementia/AD explanatory mechanisms involve a diverse array of genetic and environmental factors that interact from the early stages of life. In the future, studies across different population-based cohorts are essential to validate risk/protective factors of dementia. This evidence would help develop public health policies to decrease the incidence of dementia.

Deep Learning Models for the Screening of Cognitive Impairment Using Multimodal Fundus Images

OBJECTIVE

We aimed to develop a deep learning system capable of identifying subjects with cognitive impairment quickly and easily based on multimodal ocular images.

DESIGN

Cross sectional study.

SUBJECTS

Participants of Beijing Eye Study 2011 and patients attending Beijing Tongren Eye Center and Beijing Tongren Hospital Physical Examination Center.

METHODS

We trained and validated a deep learning algorithm to assess cognitive impairment using retrospectively collected data from the Beijing Eye Study 2011. Cognitive impairment was defined as a Mini-Mental State Examination score < 24. Based on fundus photographs and OCT images, we developed 5 models based on the following sets of images: macula-centered fundus photographs, optic disc-centered fundus photographs, fundus photographs of both fields, OCT images, and fundus photographs of both fields with OCT (multimodal). The performance of the models was evaluated and compared in an external validation data set, which was collected from patients attending Beijing Tongren Eye Center and Beijing Tongren Hospital Physical Examination Center.

MAIN OUTCOME MEASURES

Area under the curve (AUC).

RESULTS

A total of 9424 retinal photographs and 4712 OCT images were used to develop the model. The external validation sets from each center included 1180 fundus photographs and 590 OCT images. Model comparison revealed that the multimodal performed best, achieving an AUC of 0.820 in the internal validation set, 0.786 in external validation set 1, and 0.784 in external validation set 2. We evaluated the performance of the multi-model in different sexes and different age groups; there were no significant differences. The heatmap analysis showed that signals around the optic disc in fundus photographs and the retina and choroid around the macular and optic disc regions in OCT images were used by the multimodal to identify participants with cognitive impairment.

CONCLUSIONS

Fundus photographs and OCT can provide valuable information on cognitive function. Multimodal models provide richer information compared with single-mode models. Deep learning algorithms based on multimodal retinal images may be capable of screening cognitive impairment. This technique has potential value for broader implementation in community-based screening or clinic settings.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Effect of vigorous-intensity physical activity on incident cognitive impairment in high-risk hypertension

INTRODUCTION

We investigated the effect vigorous physical activity (VPA) on the risk of incident mild cognitive impairment (MCI) and probable dementia among individuals with high-risk hypertension.

METHODS

Baseline self-reported frequency of VPA was categorized into low VPA (<1 session/week), and high VPA (≥1 session/week). We used multivariate Cox regression analysis to examine the association of VPA categories with incident MCI and probable dementia events.

RESULTS

Participants in the high VPA category, compared with low VPA, experienced lower events rates (per 1000 person-years) of MCI (13.9 vs 19.7), probable dementia (6.3 vs 9.0), and MCI/probable dementia (18.5 vs 25.8). In the multivariate Cox regression model, high VPA, compared with low VPA, was associated with lower risk of MCI, probable dementia, and MCI/probable dementia (HR [95% CI]: 0.81 [0.68-0.97], 0.80 [0.63-1.03], and 0.82 [0.70-0.96]), respectively.

DISCUSSION

This study provides evidence that VPA may preserve cognitive function in high-risk patients with hypertension.

HIGHLIGHTS

Hypertension is associated with an increased risk of cognitive impairment Physical activity (PA) is associated with a lower risk of decline in cognition The effect of ≥1 sessions of vigorous-intensity PA (VPA) per week was assessed This analysis included SPRINT MIND trial participants with high-risk hypertension ≥1 VPA sessions/week was associated with lower risk of future cognitive impairment.

Loss of neuronal lysosomal acid lipase drives amyloid pathology in Alzheimer's disease

Underlying drivers of late-onset Alzheimer's disease (LOAD) pathology remain unknown. However, multiple biologically diverse risk factors share a common pathological progression. To identify convergent molecular abnormalities that drive LOAD pathogenesis we compared two common midlife risk factors for LOAD, heavy alcohol use and obesity. This revealed that disrupted lipophagy is an underlying cause of LOAD pathogenesis. Both exposures reduced lysosomal flux, with a loss of neuronal lysosomal acid lipase (LAL). This resulted in neuronal lysosomal lipid (NLL) accumulation, which opposed Aβ localization to lysosomes. Neuronal LAL loss both preceded (with aging) and promoted (targeted knockdown) Aβ pathology and cognitive deficits in AD mice. The addition of recombinant LAL ex vivo and neuronal LAL overexpression in vivo prevented amyloid increases and improved cognition. In WT mice, neuronal LAL declined with aging and correlated negatively with entorhinal Aβ. In healthy human brain, LAL also declined with age, suggesting this contributes to the age-related vulnerability for AD. In human LOAD LAL was further reduced, correlated negatively with Aβ1-42, and occurred with polymerase pausing at the LAL gene. Together, this finds that the loss of neuronal LAL promotes NLL accumulation to impede degradation of Aβ in neuronal lysosomes to drive AD amyloid pathology.

Effects of intensive lifestyle changes on the progression of mild cognitive impairment or early dementia due to Alzheimer's disease: a randomized, controlled clinical trial

BACKGROUND

Evidence links lifestyle factors with Alzheimer's disease (AD). We report the first randomized, controlled clinical trial to determine if intensive lifestyle changes may beneficially affect the progression of mild cognitive impairment (MCI) or early dementia due to AD.

METHODS

A 1:1 multicenter randomized controlled phase 2 trial, ages 45-90 with MCI or early dementia due to AD and a Montreal Cognitive Assessment (MoCA) score of 18 or higher. The primary outcome measures were changes in cognition and function tests: Clinical Global Impression of Change (CGIC), Alzheimer's Disease Assessment Scale (ADAS-Cog), Clinical Dementia Rating-Sum of Boxes (CDR-SB), and Clinical Dementia Rating Global (CDR-G) after 20 weeks of an intensive multidomain lifestyle intervention compared to a wait-list usual care control group. ADAS-Cog, CDR-SB, and CDR-Global scales were compared using a Mann-Whitney-Wilcoxon rank-sum test, and CGIC was compared using Fisher's exact test. Secondary outcomes included plasma Aβ42/40 ratio, other biomarkers, and correlating lifestyle with the degree of change in these measures.

RESULTS

Fifty-one AD patients enrolled, mean age 73.5. No significant differences in any measures at baseline. Only two patients withdrew. All patients had plasma Aβ42/40 ratios <0.0672 at baseline, strongly supporting AD diagnosis. After 20 weeks, significant between-group differences in the CGIC (p= 0.001), CDR-SB (p= 0.032), and CDR Global (p= 0.037) tests and borderline significance in the ADAS-Cog test (p= 0.053). CGIC, CDR Global, and ADAS-Cog showed improvement in cognition and function and CDR-SB showed significantly less progression, compared to the control group which worsened in all four measures. Aβ42/40 ratio increased in the intervention group and decreased in the control group (p = 0.003). There was a significant correlation between lifestyle and both cognitive function and the plasma Aβ42/40 ratio. The microbiome improved only in the intervention group (p <0.0001).

CONCLUSIONS

Comprehensive lifestyle changes may significantly improve cognition and function after 20 weeks in many patients with MCI or early dementia due to AD.

TRIAL REGISTRATION

Approved by Western Institutional Review Board on 12/31/2017 (#20172897) and by Institutional Review Boards of all sites. This study was registered retrospectively with clinicaltrials.gov on October 8, 2020 (NCT04606420, ID: 20172897).

Protein arginine methyltransferase 4 modulates nitric oxide synthase uncoupling and cerebral blood flow in Alzheimer's disease

Alzheimer's disease (AD) is the leading cause of mortality, disability, and long-term care burden in the United States, with women comprising the majority of AD diagnoses. While AD-related dementia is associated with tau and amyloid beta accumulation, concurrent derangements in cerebral blood flow have been observed alongside these proteinopathies in humans and rodent models. The homeostatic production of nitric oxide synthases (NOS) becomes uncoupled in AD which leads to decreased NO-mediated vasodilation and oxidative stress via the production of peroxynitrite (ONOO-∙) superoxide species. Here, we investigate the role of the novel protein arginine methyltransferase 4 (PRMT4) enzyme function and its downstream product asymmetric dimethyl arginine (ADMA) as it relates to NOS dysregulation and cerebral blood flow in AD. ADMA (type-1 PRMT product) has been shown to bind NOS as a noncanonic ligand causing enzymatic dysfunction. Our results from RT-qPCR and protein analyses suggest that aged (9-12 months) female mice bearing tau- and amyloid beta-producing transgenic mutations (3xTg-AD) express higher levels of PRMT4 in the hippocampus when compared to age- and sex-matched C57BL6/J mice. In addition, we performed studies to quantify the expression and activity of different NOS isoforms. Furthermore, laser speckle contrast imaging analysis was indicative that 3xTg-AD mice have dysfunctional NOS activity, resulting in reduced production of NO metabolites, enhanced production of free-radical ONOO-, and decreased cerebral blood flow. Notably, the aforementioned phenomena can be reversed via pharmacologic PRMT4 inhibition. Together, these findings implicate the potential importance of PRMT4 signaling in the pathogenesis of Alzheimer's-related cerebrovascular derangement.

Effective dosage and mode of exercise for enhancing cognitive function in Alzheimer's disease and dementia: a systematic review and Bayesian Model-Based Network Meta-analysis of RCTs

OBJECTIVE

Research the dose-response relationship between overall and certain types of exercise and cognitive function in older adults with Alzheimer's disease and dementia.

DESIGN

Systemic and Bayesian Model-Based Network Meta-Analysis.

METHODS

In our study, we analyzed data from randomized controlled trials investigating the effects of different exercises on cognitive outcomes in older adults with AD. We searched the Web of Science, PubMed, Cochrane Central Register of Controlled Trials, and Embase up to November 2023. Using the Cochrane Risk of Bias tool (Rob2) for quality assessment and R software with the MBNMA package for data analysis, we determined standard mean differences (SMDs) and 95% confidence intervals (95%CrI) to evaluate exercise's impact on cognitive function in AD.

RESULTS

Twenty-seven studies with 2,242 AD patients revealed a nonlinear relationship between exercise and cognitive improvement in AD patients. We observed significant cognitive enhancements at an effective exercise dose of up to 1000 METs-min/week (SMDs: 0.535, SD: 0.269, 95% CrI: 0.023 to 1.092). The optimal dose was found to be 650 METs-min/week (SMDs: 0.691, SD: 0.169, 95% CrI: 0.373 to 1.039), with AE (Aerobic exercise) being particularly effective. For AE, the optimal cognitive enhancement dose was determined to be 660 METs-min/week (SMDs: 0.909, SD: 0.219, 95% CrI: 0.495 to 1.362).

CONCLUSION

Nonlinear dose-response relationship between exercise and cognitive improvement in Alzheimer's disease, with the optimal AE dose identified at 660 METs-min/week for enhancing cognitive function in AD.

Experimental laboratory models as tools for understanding modifiable dementia risk

Experimental laboratory research has an important role to play in dementia prevention. Mechanisms underlying modifiable risk factors for dementia are promising targets for dementia prevention but are difficult to investigate in human populations due to technological constraints and confounds. Therefore, controlled laboratory experiments in models such as transgenic rodents, invertebrates and in vitro cultured cells are increasingly used to investigate dementia risk factors and test strategies which target them to prevent dementia. This review provides an overview of experimental research into 15 established and putative modifiable dementia risk factors: less early-life education, hearing loss, depression, social isolation, life stress, hypertension, obesity, diabetes, physical inactivity, heavy alcohol use, smoking, air pollution, anesthetic exposure, traumatic brain injury, and disordered sleep. It explores how experimental models have been, and can be, used to address questions about modifiable dementia risk and prevention that cannot readily be addressed in human studies. HIGHLIGHTS: Modifiable dementia risk factors are promising targets for dementia prevention. Interrogation of mechanisms underlying dementia risk is difficult in human populations. Studies using diverse experimental models are revealing modifiable dementia risk mechanisms. We review experimental research into 15 modifiable dementia risk factors. Laboratory science can contribute uniquely to dementia prevention.

Physical frailty, genetic predisposition, and incident dementia: a large prospective cohort study

Physical frailty and genetic factors are both risk factors for increased dementia; nevertheless, the joint effect remains unclear. This study aimed to investigated the long-term relationship between physical frailty, genetic risk, and dementia incidence. A total of 274,194 participants from the UK Biobank were included. We applied Cox proportional hazards regression models to estimate the association between physical frailty and genetic and dementia risks. Among the participants (146,574 females [53.45%]; mean age, 57.24 years), 3,353 (1.22%) new-onset dementia events were recorded. Compared to non-frailty, the hazard ratio (HR) for dementia incidence in prefrailty and frailty was 1.396 (95% confidence interval [CI], 1.294-1.506, P < 0.001) and 2.304 (95% CI, 2.030-2.616, P < 0.001), respectively. Compared to non-frailty and low polygenic risk score (PRS), the HR for dementia risk was 3.908 (95% CI, 3.051-5.006, P < 0.001) for frailty and high PRS. Furthermore, among the participants, slow walking speed (HR, 1.817; 95% CI, 1.640-2.014, P < 0.001), low physical activity (HR, 1.719; 95% CI, 1.545-1.912, P < 0.001), exhaustion (HR, 1.670; 95% CI, 1.502-1.856, P < 0.001), low grip strength (HR, 1.606; 95% CI, 1.479-1.744, P < 0.001), and weight loss (HR, 1.464; 95% CI, 1.328-1.615, P < 0.001) were independently associated with dementia risk compared to non-frailty. Particularly, precise modulation for different dementia genetic risk populations can also be identified due to differences in dementia risk resulting from the constitutive pattern of frailty in different genetic risk populations. In conclusion, both physical frailty and high genetic risk are significantly associated with higher dementia risk. Early intervention to modify frailty is beneficial for achieving primary and precise prevention of dementia, especially in those at high genetic risk.

Does Nutritional Supplementation Have a Disease-Modifying Effect on the Alzheimer's Disease Neurodegenerative Process?

Because nutrition is one of the main factors related to Alzheimer's disease (AD), questions arise about how taking nutrients as supplements can affect its pathophysiological process. In the present study, an overview of the potential effects of nutritional supplementation on the main biomarkers related to the AD pathophysiology (i.e., amyloid-β and tau) is explored. Trials testing the supplementation of single or combined nutrients versus placebo identified effects on some AD biomarkers, but changes were not always accompanied by positive effects on cognitive function. Differences in characteristics of studied populations (cognitive status, age, educational level), choice of nutrient combinations and doses, duration of intervention, and adjustments for potential confounders are some factors that may explain discrepancies in findings.

ZOom Delivered Intervention Against Cognitive decline (ZODIAC) COVID-19 pandemic adaptations to the Post-Ischaemic Stroke Cardiovascular Exercise Study (PISCES): protocol for a randomised controlled trial of remotely delivered fitness training for brain health

BACKGROUND

Stroke increases subsequent dementia risk yet there are no specific post-stroke therapies to protect cognition. Cardiorespiratory exercise is recommended for secondary prevention of stroke and may be neuroprotective. The Post Ischaemic Stroke Cardiovascular Exercise Study (PISCES) aims to reduce post-stroke secondary neurodegeneration and cognitive decline. During the pandemic, we pivoted to a ZOom Delivered Intervention Against Cognitive decline (ZODIAC) protocol, reducing pandemic-amplified barriers to exercise.

METHODS

We present pandemic adaptions for a multicentre phase IIb assessor-blinded randomised controlled trial of ischaemic stroke survivors testing the efficacy and feasibility of an 8-week home-based exercise intervention delivered at 2 months post-stroke. We compare cardiorespiratory exercise (intervention arm) versus balance and stretching (active control arm). Participants are assessed with magnetic resonance imaging (MRI), fitness, blood, microbiome, and neuropsychological tests at three study visits: before and after the exercise intervention and at 12 months. Modifications to the original protocol include pre-exercise safety home visits, commercial delivery of exercise equipment to facilitate assessor blinding, and reconsideration of statistical plan to allow pooling of the studies. We have reduced in-person study visits from 27 to 3. Primary outcome remains between-group (intervention versus control) difference in brain volume change; secondary outcome is between-group difference in global cognitive ability to allow remote administration of a validated cognitive scale.

DISCUSSION

Remotely delivered exercise interventions reduce participant burden and may reduce barriers to recruitment. A decrease in the number of in-person study visits can be supported by greater information capture via self-reported questionnaires and phone surveys.

TRIAL REGISTRATION

Prospectively ACTRN12616000942459. Registered on July 2016.

The relationship between diabetes and the dementia risk: a meta-analysis

BACKGROUND

The link between diabetes and dementia risk is not well understood. This study evaluates the factors linking diabetes to dementia onset, providing guidance for preventing dementia in diabetic patients.

METHODS

This analysis utilized databases such as PubMed, Embase, Web of Science, and the Cochrane Library to review literature from January 31, 2012, to March 5, 2023. Articles were rigorously assessed using specific inclusion and exclusion criteria. The Newcastle-Ottawa Scale (NOS) was used to evaluate the quality of the studies. Data analysis was performed with STATA 15.0.

RESULTS

The study analyzed 15 articles, covering 10,103,868 patients, with 8,821,516 diagnosed with diabetes. The meta-analysis reveals a substantial association between diabetes and an increased risk of dementia [RR: 1.59, 95%CI (1.40-1.80), P < 0.01, I²=96.4%]. A diabetes duration of less than five years is linked to a higher dementia risk [RR: 1.29, 95%CI (1.20-1.39), P < 0.01, I²=92.6%]. Additionally, hypoglycemia significantly raises dementia risk [RR: 1.56, 95%CI (1.13-2.16), P < 0.01, I²=51.5%]. Analyses of blood sugar control, glycated hemoglobin, and fasting blood sugar indicated no significant effects on the onset of dementia.

CONCLUSION

Diabetes notably increases dementia risk, particularly where diabetes duration is under five years or hypoglycemia is present.

REGISTRATION

The research protocol was registered with PROSPERO and assigned the registration number CRD42023394942.

A bibliometric analysis on the health behaviors related to mild cognitive impairment

Background

Mild cognitive impairment (MCI) is commonly defined as a transitional subclinical state between normal aging and dementia. A growing body of research indicates that health behaviors may play a protective role against cognitive decline and could potentially slow down the progression from MCI to dementia. The aim of this study is to conduct a bibliometric analysis of literature focusing on health behaviors and MCI to summarize the factors and evidence regarding the influence of health behaviors on MCI.

Methods

The study performed a bibliometric analysis by retrieving publications from the Science Citation Index and Social Sciences Citation Index sub-databases within the Web of Science Core Collection. Utilizing VOSviewer and CiteSpace software, a total of 2,843 eligible articles underwent co-citation, co-keywords, and clustering analyses. This methodology aimed to investigate the current status, trends, major research questions, and potential future directions within the research domain.

Results

The bibliometric analysis indicates that research on healthy behaviors in individuals with MCI originated in 2002 and experienced rapid growth in 2014, reflecting the increasing global interest in this area. The United States emerged as the primary contributor, accounting for more than one-third of the total scientific output with 982 articles. Journals that published the most articles on MCI-related health behaviors included "Journal of Alzheimer's Disease," "Neurobiology of Aging," "Frontiers in Aging Neuroscience," and other geriatrics-related journals. High-impact papers identified by VOSviewer predominantly cover concepts related to MCI, such as diagnostic criteria, assessment, and multifactorial interventions. Co-occurrence keyword analysis highlights five research hotspots in health behavior associated with MCI: exercise, diet, risk factors and preventive measures for dementia, cognitive decline-related biomarkers, and clinical trials.

Conclusion

This study provides a comprehensive review of literature on health behavior in individuals with MCI, emphasizing influential documents and journals. It outlines research trends and key focal points, offering valuable insights for researchers to comprehend significant contributions and steer future studies.

Exercise for frailty research frontiers: a bibliometric analysis and systematic review

Background

Exercise intervention is a method of improving and preventing frailty in old age through physical exercise and physical activity. It has a positive impact on many chronic diseases and health risk factors, in particular cardiovascular disease, metabolic disease, osteoporosis, mental health problems and cancer prevention, and exercise therapies can also fight inflammation, increase muscle strength and flexibility, improve immune function, and enhance overall health. This study was aimed to analyze research hotspots and frontiers in exercise therapies for frailty through bibliometric methods.

Methods

In this study, data of publications from 1st January 2003 to 31st August 2023 were gathered from the Web of Science Core Collection and analyzed the hotspots and frontiers of frailty research in terms of remarkable countries/regions, institutions, cited references, authors, cited journals, burst keywords, and high-frequency keywords using CiteSpace 6.2.R3 software. The PRISMA reporting guidelines were used for this study.

Results

A collection of 7,093 publications was obtained, showing an increasing trend each year. BMC Geriatrics led in publications, while Journals of Gerontology Series A-Biological Sciences and Medical Sciences dominated in citations. The United States led in centrality and publications, with the University of Pittsburgh as the most productive institution. Leocadio R had the highest publication ranking, while Fried Lp ranked first among cited authors. Keywords in the domain of exercise therapies for frailty are "frailty," "older adult," "physical activity," "exercise," and "mortality," with "sarcopenia" exhibiting the greatest centrality. The keywords formed 19 clusters, namely "#0 older persons," "#1 mortality," "#2 muscle strength," "#3 bone mineral density," "#4 muscle mass," "#5 older adults," "#6 older people," "#7 women's health," "#8 frail elderly," "#9 heart failure," "#10 geriatric assessment," "#11 comprehensive geriatric assessment," "#12 outcm," "#13 alzheimers disease," "#14 quality of life," "#15 health care," "#16 oxidative stress," "#17 physical activity," and "#18 protein."

Conclusion

This study presents the latest developments and trends in research on frailty exercise intervention treatments over the past 20 years using CiteSpace visualization software. Through systematic analyses, partners, research hotspots and cutting-edge directions were revealed, providing a guiding basis for future research.

Clinical trajectories preceding incident dementia up to 15 years before diagnosis: a large prospective cohort study

BACKGROUND

Dementia has a long prodromal stage with various pathophysiological manifestations; however, the progression of pre-diagnostic changes remains unclear. We aimed to determine the evolutional trajectories of multiple-domain clinical assessments and health conditions up to 15 years before the diagnosis of dementia.

METHODS

Data was extracted from the UK-Biobank, a longitudinal cohort that recruited over 500,000 participants from March 2006 to October 2010. Each demented subject was matched with 10 healthy controls. We performed logistic regressions on 400 predictors covering a comprehensive range of clinical assessments or health conditions. Their evolutional trajectories were quantified using adjusted odds ratios (ORs) and FDR-corrected p-values under consecutive timeframes preceding the diagnosis of dementia.

FINDINGS

During a median follow-up of 13.7 [Interquartile range, IQR 12.9-14.2] years until July 2022, 7620 subjects were diagnosed with dementia. In general, upon approaching the diagnosis, demented subjects witnessed worse functional assessments and a higher prevalence of health conditions. Associations up to 15 years preceding the diagnosis comprised declined physical strength (hand grip strength, OR 0.65 [0.63-0.67]), lung dysfunction (peak expiratory flow, OR 0.78 [0.76-0.81]) and kidney dysfunction (cystatin C, OR 1.13 [1.11-1.16]), comorbidities of coronary heart disease (OR 1.78 [1.67-1.91]), stroke (OR 2.34 [2.1-1.37]), diabetes (OR 2.03 [1.89-2.18]) and a series of mental disorders. Cognitive functions in multiple tests also demonstrate decline over a decade before the diagnosis. Inadequate activity (3-5 year, overall time of activity, OR 0.82 [0.73-0.92]), drowsiness (3-5 year, sleep duration, OR 1.13 [1.04-1.24]) and weight loss (0-5 year, weight, OR 0.9 [0.83-0.98]) only exhibited associations within five years before the diagnosis. In addition, serum biomarkers of enriched endocrine, dysregulations of ketones, deficiency of brand-chain amino acids and polyunsaturated fatty acids were found in a similar prodromal time window and can be witnessed as the last pre-symptomatic conditions before the diagnosis.

INTERPRETATION

Our findings present a comprehensive temporal-diagnostic landscape preceding incident dementia, which could improve selection for preventive and early disease-modifying treatment trials.

Depressive symptoms and cognitive decline in older adults

OBJECTIVES

Few studies have examined the impact of late-life depression trajectories on specific domains of cognitive function. This study aims to delineate how different depressive symptom trajectories specifically affect cognitive function in older adults.

DESIGN

Prospective longitudinal cohort study.

SETTING

Australia and the United States of America.

PARTICIPANTS

In total, 11,035 community-dwelling older adults with a mean age of 75 years.

MEASUREMENTS

Depressive trajectories were modelled from depressive symptoms according to annual Centre for Epidemiological Studies Depression Scale 10 (CES-D-10) surveys. Four trajectories of depressive symptoms were identified: low ("nondepressed"), consistently mild ("subthreshold depression"), consistently moderate ("persistent depression"), and initially low but increasing ("emerging depression"). Global cognition (Modified Mini-Mental State Examination [3MS]), verbal fluency (Controlled Oral Word Association Test [COWAT]), processing speed (Symbol Digit Modalities Test [SDMT]), episodic memory (Hopkins Verbal Learning Test - Revised [HVLT-R]), and a composite z-score were assessed over a subsequent median 2 years.

RESULTS

Subthreshold depression predicted impaired performance on the SDMT (Cohen's d -0.04) and composite score (-0.03); emerging depression predicted impaired performance on the SDMT (-0.13), HVLT-R (-0.09), 3 MS (-0.08) and composite score (-0.09); and persistent depression predicted impaired performance on the SDMT (-0.08), 3 MS (-0.11), and composite score (-0.09).

CONCLUSIONS

Depressive symptoms are associated with later impaired processing speed. These effects are small. Diverse depression trajectories have different impacts on cognitive function.

Impact of dementia status on intravenous thrombolysis and endovascular treatment for acute ischemic stroke: Retrospective study

INTRODUCTION

Individuals with dementia are underrepresented in interventional studies for acute ischemic stroke (AIS). This research gap creates a bias against their treatment in clinical practice. Our goal was to compare the safety and efficacy of intravenous-thrombolysis (t-PA) and endovascular treatment (EVT) in individuals with or without pre-AIS dementia.

METHOD

A retrospective study of AIS patients receiving t-PA or EVT between 2019 and 2022. Patients were classified as dementia on a case-by-case review of baseline assessment. Additional variables included demographic, vascular risk factors, AIS severity and treatment. Outcomes of interest were intracerebral hemorrhage, mortality in 90-days, and the difference in modified rankin scale (mRS) before AIS and in 90-days follow-up. Outcomes were compared across non-matched groups and following propensity-score matching.

RESULTS

Altogether, 628 patients were included, of which 68 had pre-AIS dementia. Compared to non-dementia group, dementia group were older, had a higher rate of vascular risk factors, higher pre-stroke mRS and higher baseline NIHSS. Individuals with dementia had higher rates of mortality (25% vs.11%,p < 0.01) on non-matched comparison. All cohort and restricted t-PA EVT matched analysis showed no difference in any outcome. Regression analysis confirmed that AIS severity at presentation and its treatment, not dementia, were the chief contributors to patients' outcomes.

DISCUSSION

Our results indicate that pre-AIS dementia does not impact the efficacy or safety of EVT or t-PA for AIS. We thus call for more inclusive research on stroke therapy with regards to baseline cognitive status. Such studies are urgently required to inform stroke guidelines and enhance care.

Cognitive reserve over the life course and risk of dementia: a systematic review and meta-analysis

Background

The number of people with dementia is soaring. Cognitive reserve has been thought to be associated with dementia risk. It is not clear at which period in the life course and which cognitive reserve proxies contribute to the reduced risk of dementia.

Methods

By scanning four databases (PubMed, Embase, Web of Science, and MEDLINE) up to Jun 3, 2023, longitudinal studies of life-course cognitive reserve and risk of dementia were found. The HRs and 95% CIs for each study were summarized using random effects models. Subgroup analyses and sensitivity analyses were conducted. Utilizing funnel plots, Begg and Egger tests, publication bias was investigated.

Results

A total of 27 studies were included, containing 10 in early-life, 10 in middle-life, and 13 in late-life. All studies used validated questionnaires to measure cognitive reserve, and dementia diagnosis followed recognized worldwide guidelines. All included studies were of medium or low risk. Cognitive reserve in early-life (Hazard ratio (HR): 0.82; 95% confidence interval (CI): 0.79-0.86), middle-life (HR: 0.91; 95% CI: 0.84-0.98) and late-life (HR: 0.81; 95% CI: 0.75-0.88) all have protective effects on dementia risk. Multiple sensitivity analyses showed consistent results.

Conclusion

Dementia risk is reduced by the buildup of cognitive reserves during life-course. Accumulation of proxies for cognitive reserve in early and late life had the greatest effect on dementia risk reduction. Social connection may be an effective approach to lower dementia risk.

Predictors for survival in patients with Alzheimer's disease: a large comprehensive meta-analysis

The prevalence of Alzheimer's disease (AD) is increasing as the population ages, and patients with AD have a poor prognosis. However, knowledge on factors for predicting the survival of AD remains sparse. Here, we aimed to systematically explore predictors of AD survival. We searched the PubMed, Embase and Cochrane databases for relevant literature from inception to December 2022. Cohort and case-control studies were selected, and multivariable adjusted relative risks (RRs) were pooled by random-effects models. A total of 40,784 reports were identified, among which 64 studies involving 297,279 AD patients were included in the meta-analysis after filtering based on predetermined criteria. Four aspects, including demographic features (n = 7), clinical features or comorbidities (n = 13), rating scales (n = 3) and biomarkers (n = 3), were explored and 26 probable prognostic factors were finally investigated for AD survival. We observed that AD patients who had hyperlipidaemia (RR: 0.69) were at a lower risk of death. In contrast, male sex (RR: 1.53), movement disorders (including extrapyramidal signs) (RR: 1.60) and cancer (RR: 2.07) were detrimental to AD patient survival. However, our results did not support the involvement of education, hypertension, APOE genotype, Aβ42 and t-tau in AD survival. Our study comprehensively summarized risk factors affecting survival in patients with AD, provided a better understanding on the role of different factors in the survival of AD from four dimensions, and paved the way for further research.

Associations between cognitive function and lifestyle in community-living older people: a correlational study

BACKGROUND

Previous studies have examined relationship between cognitive function and lifestyle; however, the nature of this relationship is expected to vary in diverse cultural and low-income setting where lifestyle practices differ from those in high-income countries.

AIM

This study aims to investigate the correlation between lifestyle factors and cognitive function among individuals aged 60 years and older in 2021.

METHODS

This cross-sectional, Community-based study involved 300 older adults from comprehensive urban health centers in Khorramabad, Iran, selected through stratified cluster sampling. Data were collected using the demographic information questionnaire, Mini-Mental State Examination, and Lifestyle Questionnaire. Data management and analysis were performed using SPSS (version 22) and independent t-tests, Pearson's correlation coefficient, ANOVA, and multiple linear regression analysis were used. A p value < 0.05 was considered significant.

RESULTS

The study included 156 males (52%) and 144 females (48%). Findings revealed a significant correlation between cognitive function and lifestyle (P < 0.001). Multiple linear regression analysis indicated that physical health, environmental health, exercise, accident prevention, and avoidance of medication exerted the most significant positive effect on cognitive function. Conversely, social health exhibited a notable negative influence on cognitive function. (P < 0.001).

CONCLUSION

The results suggest that specific aspects of lifestyle, such as physical health, accident prevention, and avoidance of medication are associated with cognitive function in older adults. Consequently, lifestyle promotion programs may enhance cognitive function and improve the quality of life among older adults.

Multidomain interventions based on a life-course model to prevent dementia in at-risk Chinese older adults: A randomized controlled trial

BACKGROUND

Due to the time-dependent effect of specific risk factors for dementia, multidomain interventions based on a life-course model might achieve optimal preventive effects against dementia.

OBJECTIVE

The purpose of this study was to investigate the effectiveness of multidomain interventions based on a life-course model of modifiable risk factors for dementia in at-risk Chinese older adults.

DESIGN

This was a two-arm, proof-of-concept, randomized controlled trial.

SETTING AND PARTICIPANTS

We randomly assigned 96 community-dwelling at-risk adults aged 60 years or older in a 1:1 ratio to either the 6-month multidomain intervention group (dementia literacy, physical activity, cognitive training, social activity and optional modules) or the control group (health education).

METHODS

The primary outcomes were the dementia risk score and cognitive composite Z score. The secondary outcomes included the individual components of the dementia risk score (protective and risk factors) and cognitive composite Z score (global cognition, memory, executive function and language), social isolation (loneliness, social contact, and social participation), dementia literacy and prevention belief. Linear mixed models with maximum likelihood estimation were used to calculate the outcomes between the groups over time.

RESULTS

The primary analyses showed that the dementia risk score was significantly lower (p < 0.001) and that the cognitive composite Z score was significantly higher (p = 0.013) in the multidomain intervention group than in the control group. Baseline characteristics did not modify the effects of the multidomain interventions (p value for interaction > 0.05). For secondary outcomes, statistically significant group × time interactions were observed for the protective (p = 0.001) and risk factors (p = 0.049), as well as in executive function (p = 0.020), loneliness (p = 0.029), dementia literacy (p < 0.001) and prevention belief (p < 0.001).

CONCLUSIONS

Multidomain interventions based on a life-course model are feasible and have the potential to reduce dementia risk and improve cognitive function in at-risk Chinese older adults.

REGISTRATION

The trial was registered at the Chinese Clinical Trials Registry (ChiCTR2100053417).

A retrospective analysis of serious adverse events and deaths in U.S.-based lifestyle clinical trials for cognitive health

Objective

This retrospective analysis examined serious adverse events (SAEs) and deaths in U.S. lifestyle clinical trials aimed at enhancing cognitive health in older adults.

Methods

Data was gathered from trials completed between January 1, 2000, and July 19, 2023, via ClinicalTrials.gov's API.

Results

Among these trials, 76% did not report results. The remaining studies fell into four intervention categories: Cognitive/Behavioral, Exercise/Movement, Diet/Supplement, and Multi-modal. When considering all trial types collectively, the findings suggest that lifestyle clinical trials are generally safe. There was no significant increase in the relative risk of experiencing an SAE in the intervention group compared to the control group. However, in terms of relative risk of death, an increase of 28% was observed in the intervention compared to the control, which was statistically significant (X2 (1, N = 36), p < 0.00688). Nevertheless, this increase did not surpass age-adjusted U.S. mortality rates. Assessing the data by intervention type, Diet/Supplement, and Multi-modal trials displayed an elevated relative risk of SAEs in the intervention. Diet/Supplement trials had a 16% increase (X2 (1, N = 2), p < 0.0263), and Multi-modal trials had a 365% increase (X2 (1, N = 5), p < 0.000213). Diet/Supplement trials also showed a 67% increased risk of death (X2 (1, N = 2), p < 0.000197).

Conclusions

These findings should be cautiously considered due to the low rate of reporting, but underscore the significance of reporting clinical trial results, enhancing transparency, and facilitating more accurate safety assessments in cognitive aging and lifestyle interventions for older adults.

Transplantation of beige adipose organoids fabricated using adipose acellular matrix hydrogel improves metabolic dysfunction in high-fat diet-induced obesity and type 2 diabetes mice

Transplantation of brown adipose tissue (BAT) is a promising approach for treating obesity and metabolic disorders. However, obtaining sufficient amounts of functional BAT or brown adipocytes for transplantation remains a major challenge. In this study, we developed a hydrogel that combining adipose acellular matrix (AAM) and GelMA and HAMA that can be adjusted for stiffness by modulating the duration of light-crosslinking. We used human white adipose tissue-derived microvascular fragments to create beige adipose organoids (BAO) that were encapsulated in either a soft or stiff AAM hydrogel. We found that BAOs cultivated in AAM hydrogels with high stiffness demonstrated increased metabolic activity and upregulation of thermogenesis-related genes. When transplanted into obese and type 2 diabetes mice, the HFD + BAO group showed sustained improvements in metabolic rate, resulting in significant weight loss and decreased blood glucose levels. Furthermore, the mice showed a marked reduction in nonalcoholic liver steatosis, indicating improved liver function. In contrast, transplantation of 2D-cultured beige adipocytes failed to produce these beneficial effects. Our findings demonstrate the feasibility of fabricating beige adipose organoids in vitro and administering them by injection, which may represent a promising therapeutic approach for obesity and diabetes.

Amyloid pathology mediates the associations between plasma fibrinogen and cognition in non-demented adults

Though previous studies revealed the potential associations of elevated levels of plasma fibrinogen with dementia, there is still limited understanding regarding the influence of Alzheimer's disease (AD) biomarkers on these associations. We sought to investigate the interrelationships among fibrinogen, cerebrospinal fluid (CSF) AD biomarkers, and cognition in non-demented adults. We included 1996 non-demented adults from the Chinese Alzheimer's Biomarker and LifestylE (CABLE) study and 337 from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database. The associations of fibrinogen with AD biomarkers and cognition were explored using multiple linear regression models. The mediation analyses with 10 000 bootstrapped iterations were conducted to explore the mediating effects of AD biomarkers on cognition. In addition, interaction analyses and subgroup analyses were conducted to assess the influence of covariates on the relationships between fibrinogen and AD biomarkers. Participants exhibiting low Aβ42 were designated as A+, while those demonstrating high phosphorylated tau (P-tau) and total tau (Tau) were labeled as T+ and N+, respectively. Individuals with normal measures of Aβ42 and P-tau were categorized as the A-T- group, and those with abnormal levels of both Aβ42 and P-tau were grouped under A+T+. Fibrinogen was higher in the A+ subgroup compared to that in the A- subgroup (p = 0.026). Fibrinogen was higher in the A+T+ subgroup compared to that in the A-T- subgroup (p = 0.011). Higher fibrinogen was associated with worse cognition and Aβ pathology (all p < 0.05). Additionally, the associations between fibrinogen and cognition were partially mediated by Aβ pathology (mediation proportion range 8%-28%). Interaction analyses and subgroup analyses showed that age and ApoE ε4 affect the relationships between fibrinogen and Aβ pathology. Fibrinogen was associated with both cognition and Aβ pathology. Aβ pathology may be a critical mediator for impacts of fibrinogen on cognition.

Efficacy of Magnesium Sulfate and Labetalol in the Treatment of Pregnancy-Induced Hypertension and Its Effect on Anxiety and Depression: A Retrospective Cohort Study

Background

In this study, the effect of magnesium sulfate and labetalol in treating pregnancy-induced hypertension (PIH) and its influence on anxiety and depression in patients are observed, and new ideas for treating anxiety and depression in PIH are introduced.

Methods

A retrospective cohort study was conducted to select patients with PlH diagnosed from July 2020 to July 2023 from Affiliated Hospital of Electronic Science and Technology University and Chengdu Women' s and Children's Central Hospital in Chengdu of Sichuan Province. The changes in blood pressure, Edinburgh Postnatal Depression Scale (EPDS), and generalized anxiety disorder 7 (GAD-7) in patients with hypertensive pregnancy were collected and analyzed.

Results

In our investigation, 219 patients completed the study, and 36.1% (79/219) of them developed anxiety and depression. According to whether the patients were treated with magnesium sulfate and labetalol, 49 cases were assigned to the magnesium sulfate and labetalol treatment (MSLT) group, and 30 cases were assigned to the conventional treatment (CT) group. Edinburgh Postnatal Depression Scale scores and GAD-7 scores in the MSLT group were significantly lower than those in the CT group, indicating that magnesium sulfate and labetalol can improve anxiety and depression in hypertensive patients during pregnancy. The difference was statistically significant (P < .05). According to the changes in systolic blood pressure, the clinical efficacy of patients was evaluated, and no significant difference in efficacy existed between the MSLT and CT groups.

Conclusion

Magnesium sulfate and labetalol can control the blood pressure of patients with PIH and indirectly improve anxiety and depression in patients with PIH, thereby introducing new ideas for the treatment of PIH accompanied by anxiety and depression.

Exercise as medicine in Parkinson's disease

Parkinson's disease (PD) is an incurable and progressive neurological disorder leading to deleterious motor and non-motor consequences. Presently, no pharmacological agents can prevent PD evolution or progression, while pharmacological symptomatic treatments have limited effects in certain domains and cause side effects. Identification of interventions that prevent, slow, halt or mitigate the disease is therefore pivotal. Exercise is safe and represents a cornerstone in PD rehabilitation, but exercise may have even more fundamental benefits that could change clinical practice. In PD, the existing knowledge base supports exercise as (1) a protective lifestyle factor preventing the disease (ie, primary prevention), (2) a potential disease-modifying therapy (ie, secondary prevention) and (3) an effective symptomatic treatment (ie, tertiary prevention). Based on current evidence, a paradigm shift is proposed, stating that exercise should be individually prescribed as medicine to persons with PD at an early disease stage, alongside conventional medical treatment.

Preliminary study on early diagnosis of Alzheimer's disease in APP/PS1 transgenic mice using multimodal magnetic resonance imaging

Alzheimer's disease (AD) has an insidious onset and lacks clear early diagnostic markers, and by the time overt dementia symptoms appear, the disease is already in the mid-to-late stages. The search for early diagnostic markers of AD may open a critical window for Alzheimer's treatment and facilitate early intervention to slow the progression of AD. In this study, we aimed to explore the imaging markers for early diagnosis of AD through the combined application of structural magnetic resonance imaging (sMRI), resting-state functional magnetic resonance imaging (rs-fMRI), and 1H-magnetic resonance spectroscopy (1H-MRS) multimodal magnetic resonance imaging (MRI) techniques at the animal experimental level, with the aim to provide a certain reference for early clinical diagnosis of AD. First, sMRI scans were performed on 4-month-old amyloid beta precursor protein/presenilin 1 (APP/PS1) transgenic AD model mice and wild type mice of the same litter using a 7.0 T animal MRI scanner to analyze the differential brain regions with structural changes in the gray matter of the brain by voxel-based morphometry (VBM). Next, rs-fMRI scans were performed to analyze the differential brain regions between groups for local spontaneous brain activity and functional connectivity (FC) between brain regions. Finally, 1H-MRS scans were performed to quantify and analyze intergroup differences in the relative concentrations of different metabolites within regions of interest (cortex and hippocampus). Compared with wild type mice, the volume of the left hippocampus, and right olfactory bulb of APP/PS1 transgenic AD model mice were reduced, the functional activity of the bilateral hippocampus, right piriform cortex and right caudate putamen was reduced, the functional network connectivity of the hippocampus was impaired, and the relative content of N-acetylaspartate (NAA)in the hippocampus was decreased. In addition, this study found that imaging changes in olfactory-related brain regions were closely associated with AD diagnosis, and these findings may provide some reference for the early diagnosis of AD.

Risk of Dementia Among Patients With Diabetes in a Multidisciplinary, Primary Care Management Program

Importance

Although poorly controlled diabetes is associated with a higher incidence of dementia, few studies have examined the association of diabetes management interventions with dementia incidence.

Objective

To examine the association of receiving a multidisciplinary diabetes management program (the Risk Assessment and Management Program-Diabetes Mellitus [RAMP-DM]) that enables better glycemic control with subsequent risk of dementia incidence and the association of dementia with glycemic control.

Design, Setting, and Participants

This territory-wide, retrospective, matched cohort study with more than 8 years of follow-up was conducted using electronic health care records from all the patients who used public health care services in Hong Kong from 2011 to 2019. Eligible participants included all patients with type 2 diabetes (T2D) who were managed in primary care settings. Patients who received RAMP-DM were matched in a 1:1 ratio with patients who received usual care only. Data analysis occurred from April 2023 to July 2023.

Exposures

Diagnosis of T2D, hemoglobin A1C (HbA1C) level, and attendance at a general outpatient clinic or family medicine clinic. Patients received either RAMP-DM or usual care.

Main Outcomes and Measures

Incidence of all-cause dementia and subtypes of dementia were compared between the RAMP-DM and usual care participants using a Cox proportional hazard model with other baseline characteristics, biomarkers, and medication history adjusted. HbA1C levels were measured as a secondary outcome.

Results

Among the 55 618 matched participants (mean [SD] age, 62.28 [11.90] years; 28 561 female [51.4%]; 27 057 male [48.6%]), including the 27 809 patients in the RAMP-DM group and 27 809 patients in the usual care group, patients had been diagnosed with T2D for a mean (SD) of 5.90 (4.20) years. During a median (IQR) follow-up period of 8.4 (6.8-8.8) years, 1938 patients in the RAMP-DM group (6.97%) and 2728 patients in the usual care group (9.81%) received a diagnosis of dementia. Compared with those receiving usual care, RAMP-DM participants had a lower risk of developing all-cause dementia (adjusted hazard ratio [aHR], 0.72; 95% CI, 0.68-0.77; P < .001), Alzheimer disease (aHR, 0.85; 95% CI, 0.76-0.96; P = .009), vascular dementia (aHR, 0.61; 95% CI, 0.51-0.73; P < .001), and other or unspecified dementia (aHR, 0.71; 95% CI, 0.66-0.77; P < .001). Compared with having a mean HbA1C level during the first 3 years after cohort entry between 6.5% and 7.5%, a higher risk of dementia incidence was detected for patients with a 3-year mean HbA1C level greater than 8.5% (aHR, 1.54; 95% CI, 1.31-1.80]), between 7.5% and 8.5% (aHR, 1.33; 95% CI, 1.19-1.48), between 6% and 6.5% (aHR, 1.17; 95% CI, 1.07-1.29), and 6% or less (aHR, 1.39; 95% CI, 1.24-1.57).

Conclusions and Relevance

In this cohort study of patients with T2D, the findings strengthened evidence of an association of glycemic control with dementia incidence, and revealed that a multidisciplinary primary care diabetes management program was associated with beneficial outcomes for T2D patients against dementia and its major subtypes. A moderate glycemic control target of HbA1C between 6.5% and 7.5% was associated with lower dementia incidence.

HIF-1α serves as a co-linker between AD and T2DM

Alzheimer's disease (AD)-related brain deterioration is linked to the type 2 diabetes mellitus (T2DM) features hyperglycemia, hyperinsulinemia, and insulin resistance. Hypoxia as a common risk factor for both AD and T2DM. Hypoxia-inducible factor-1 alpha (HIF-1α) acts as the main regulator of the hypoxia response and may be a key target in the comorbidity of AD and T2DM. HIF-1α expression is closely related to hyperglycemia, insulin resistance, and inflammation. Tissue oxygen consumption disrupts HIF-1α homeostasis, leading to increased reactive oxygen species levels and the inhibition of insulin receptor pathway activity, causing neuroinflammation, insulin resistance, abnormal Aβ deposition, and tau hyperphosphorylation. HIF-1α activation also leads to the deposition of Aβ by promoting the abnormal shearing of amyloid precursor protein and inhibiting the degradation of Aβ, and it promotes tau hyperphosphorylation by activating oxidative stress and the activation of astrocytes, which further exasperates AD. Therefore, we believe that HIF-α has great potential as a target for the treatment of AD. Importantly, the intracellular homeostasis of HIF-1α is a more crucial factor than its expression level.

Aberrant microstructural integrity of white matter in mild and severe orthostatic hypotension: A NODDI study

OBJECTIVE

Scarce evidence is available to elucidate the association between the abnormal microstructure of white matter (WM) and cognitive performance in patients with orthostatic hypotension (OH). This study investigated the microstructural integrity of WM in patients with mild OH (MOH) and severe OH (SOH) and evaluated the association of abnormal WM microstructure with the broad cognitive domains and cognition-related plasma biomarkers.

METHODS

Our study included 72 non-OH (NOH), 17 MOH, and 11 SOH participants. Across the groups, the WM integrity was analyzed by neurite orientation dispersion and density imaging (NODDI), and differences in WM microstructure were evaluated by nonparametric tests and post hoc models. The correlations between WM microstructure and broad cognitive domains and cognition-related plasma biomarkers were assessed by Spearman's correlation analysis.

RESULTS

The abnormal WM microstructure was localized to the WM fiber bundles in MOH patients but distributed widely in SOH cohorts (p < 0.05). Further analysis showed that the neurite density index of the left cingulate gyrus was negatively associated with amyloid β-40, glial fibrillary acidic protein, neurofilament light chain, phospho-tau181 (p < 0.05) but positively with global cognitive function (MOCA, MMSE, AER-III), memory, attention, language, language fluency, visuospatial function and amyloid β-40 / amyloid β-42 (p < 0.05). Additionally, other abnormal WM microstructures of OH were associated with broad cognitive domains and cognition-related plasma biomarkers to varying degrees.

CONCLUSION

The findings evidence that abnormal WM microstructures may present themselves as early as in the MOH phase and that these structural abnormalities are associated with cognitive functions and cognition-related plasma biomarkers.

Empowerment-based cognitive behavioural therapy for insomnia in persons with mild cognitive impairment: A sequential explanatory mixed-method pilot study

Insomnia is an emerging risk factor for the onset of mild cognitive impairment (MCI) and its progression to dementia. Impaired cognition and neuropsychiatric symptoms create challenges for persons with MCI to participate actively in non-pharmacological interventions. This study examined the feasibility and preliminary effects of empowerment-based cognitive-behavioural therapy for insomnia (CBT-I) on sleep, cognitive function, and health-related quality of life (HRQoL) in persons with MCI and sleep problems. Sixty participants were randomly allocated to the intervention or control group to receive empowerment-based CBT-I or usual care, respectively. The 12 week intervention comprised all core CBT-I techniques delivered through a group and individualised face-to-face approach. An empowerment approach with interactive teaching methods, goal setting, and action planning was used to deliver the intervention. Outcome measures included subjective and objective sleep quality and pattern, and a battery of neuropsychological tests and the 12-item Short Form Survey were administered 3 months (T1) and 6 months post-randomisation (T2). This intervention is feasible and highly acceptable for persons with MCI. The intervention group showed significant improvements in subjective and objective sleep-related outcomes compared with the control group. Moreover, the intervention group showed greater improvements in global cognition, processing speed, attention, and mental flexibility than the control group at T1 and/or T2. No significant between-group differences were observed in memory or HRQoL scores. The qualitative data converged with the quantitative data. In conclusion, empowerment-based CBT-I was well received by persons with MCI and had potential positive effects on improving sleep and cognition in this cohort.

Breaking barriers: a statistical and machine learning-based hybrid system for predicting dementia

Introduction: Dementia is a condition (a collection of related signs and symptoms) that causes a continuing deterioration in cognitive function, and millions of people are impacted by dementia every year as the world population continues to rise. Conventional approaches for determining dementia rely primarily on clinical examinations, analyzing medical records, and administering cognitive and neuropsychological testing. However, these methods are time-consuming and costly in terms of treatment. Therefore, this study aims to present a noninvasive method for the early prediction of dementia so that preventive steps should be taken to avoid dementia. Methods: We developed a hybrid diagnostic system based on statistical and machine learning (ML) methods that used patient electronic health records to predict dementia. The dataset used for this study was obtained from the Swedish National Study on Aging and Care (SNAC), with a sample size of 43040 and 75 features. The newly constructed diagnostic extracts a subset of useful features from the dataset through a statistical method (F-score). For the classification, we developed an ensemble voting classifier based on five different ML models: decision tree (DT), naive Bayes (NB), logistic regression (LR), support vector machines (SVM), and random forest (RF). To address the problem of ML model overfitting, we used a cross-validation approach to evaluate the performance of the proposed diagnostic system. Various assessment measures, such as accuracy, sensitivity, specificity, receiver operating characteristic (ROC) curve, and Matthew's correlation coefficient (MCC), were used to thoroughly validate the devised diagnostic system's efficiency. Results: According to the experimental results, the proposed diagnostic method achieved the best accuracy of 98.25%, as well as sensitivity of 97.44%, specificity of 95.744%, and MCC of 0.7535. Discussion: The effectiveness of the proposed diagnostic approach is compared to various cutting-edge feature selection techniques and baseline ML models. From experimental results, it is evident that the proposed diagnostic system outperformed the prior feature selection strategies and baseline ML models regarding accuracy.

Late-Life High Blood Pressure and Enlarged Perivascular Spaces in the Putaminal Regions of Community-Dwelling Japanese Older Persons

BACKGROUND

Enlarged perivascular spaces (EPVS) of the brain may be involved in dementia, such as Alzheimer's disease and cerebral small vessel disease (CSVD). Hypertension has been reported to be a risk factor for dementia and CSVD, but the association between blood pressure (BP) and perivascular spaces is still unclear. The aim of this study was to determine the association between BP and EPVS volumes and to examine the interactions of relevant factors.

METHODS

A total of 9296 community-dwelling subjects aged ≥65 years participated in a brain magnetic resonance imaging and health status screening examination. Perivascular volume was measured using a software package based on deep learning that was developed in-house. The associations between BP and EPVS volumes were examined by analysis of covariance and multiple regression analysis.

RESULTS

Mean EPVS volumes increased significantly with rising systolic and diastolic BP levels (P for trend = .003, P for trend<.001, respectively). In addition, mean EPVS volumes increased significantly for every 1-mmHg-increment in systolic and diastolic BPs (both P values <.001). These significant associations were still observed in the sensitivity analysis after excluding subjects with dementia.

CONCLUSIONS

The present data suggest that higher systolic and diastolic BP levels are associated with greater EPVS volumes in cognitively normal older people.

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.

Associations of liver dysfunction with incident dementia, cognition, and brain structure: A prospective cohort study of 431 699 adults

The relationship between liver dysfunction and dementia has been researched extensively but remains poorly understood. In this study, we investigate the longitudinal and cross-sectional associations between liver function and liver diseases and risk of incident dementia, impaired cognition, and brain structure abnormalities using Cox proportion hazard model and linear regression model. 431 699 participants with a mean of 8.65 (standard deviation [SD] 2.61) years of follow-up were included from the UK Biobank; 5542 all-cause dementia (ACD), 2427 Alzheimer's disease (AD), and 1282 vascular dementia (VaD) cases were documented. We observed that per SD decreases in alanine transaminase (ALT; hazard ratio [HR], 0.917; PFDR  <0.001) and per SD increases in aspartate aminotransferase (AST; HR, 1.048; PFDR  = 0.010), AST to ALT ratio (HR, 1.195; PFDR  <0.001), gamma-glutamyl transpeptidase (GGT; HR, 1.066; PFDR  <0.001), alcoholic liver disease (ALD; HR, 2.872; PFDR  <0.001), and fibrosis and cirrhosis of liver (HR, 2.285; PFDR  = 0.002), being significantly associated with a higher risk of incident ACD. Restricted cubic spline models identified a strong U-shaped association between Alb and AST and incident ACD (Pnonlinear  <0.05). Worse cognition was positively correlated with AST, AST to ALT ratio, direct bilirubin (DBil), and GGT; negatively correlated with ALT, Alb, and total bilirubin (TBil); and ALD and fibrosis and cirrhosis of liver (PFDR  <0.05). Moreover, changes in ALT, GGT, AST to ALT ratio, and ALD were significantly associated with altered cortical and subcortical regions, including hippocampus, amygdala, thalamus, pallidum, and fusiform (PFDR  <0.05). In sensitivity analysis, metabolic dysfunction-associated steatotic liver disease (MASLD) was associated with the risk of ACD and brain subcortical changes. Our findings provide substantial evidence that liver dysfunction may be an important factor for incident dementia. Early intervention in the unhealthy liver may help prevent cognitive impairment and dementia incidence.

Alzheimer's Disease in Lebanon: Exploring Genetic and Environmental Risk Factors-A Comprehensive Review

Alzheimer's disease (AD) is a neurodegenerative condition that displays a high prevalence in Lebanon causing a local burden in healthcare and socio-economic sectors. Unfortunately, the lack of prevalence studies and clinical trials in Lebanon minimizes the improvement of AD patient health status. In this review, we include over 155 articles to cover the different aspects of AD ranging from mechanisms to possible treatment and management tools. We highlight some important modifiable and non-modifiable risk factors of the disease including genetics, age, cardiovascular diseases, smoking, etc. Finally, we propose a hypothetical genetic synergy model between APOE4 and TREM2 genes which constitutes a potential early diagnostic tool that helps in reducing the risk of AD based on preventative measures decades before cognitive decline. The studies on AD in Lebanon and the Middle East are scarce. This review points out the importance of genetic mapping in the understanding of disease pathology which is crucial for the emergence of novel diagnostic tools. Hence, we establish a rigid basis for further research to identify the most influential genetic and environmental risk factors for the purpose of using more specific diagnostic tools and possibly adopting a local management protocol.

Biomaterials-based anti-inflammatory treatment strategies for Alzheimer's disease

The current therapeutic drugs for Alzheimer's disease only improve symptoms, they do not delay disease progression. Therefore, there is an urgent need for new effective drugs. The underlying pathogenic factors of Alzheimer's disease are not clear, but neuroinflammation can link various hypotheses of Alzheimer's disease; hence, targeting neuroinflammation may be a new hope for Alzheimer's disease treatment. Inhibiting inflammation can restore neuronal function, promote neuroregeneration, reduce the pathological burden of Alzheimer's disease, and improve or even reverse symptoms of Alzheimer's disease. This review focuses on the relationship between inflammation and various pathological hypotheses of Alzheimer's disease; reports the mechanisms and characteristics of small-molecule drugs (e.g., nonsteroidal anti-inflammatory drugs, neurosteroids, and plant extracts); macromolecule drugs (e.g., peptides, proteins, and gene therapeutics); and nanocarriers (e.g., lipid-based nanoparticles, polymeric nanoparticles, nanoemulsions, and inorganic nanoparticles) in the treatment of Alzheimer's disease. The review also makes recommendations for the prospective development of anti-inflammatory strategies based on nanocarriers for the treatment of Alzheimer's disease.

Toward digitally screening and profiling AD: A GAMLSS approach of MemTrax in China

PURPOSES

To establish a normative range of MemTrax (MTx) metrics in the Chinese population.

METHODS

The correct response percentage (MTx-%C) and mean response time (MTx-RT) were obtained and the composite scores (MTx-Cp) calculated. Generalized additive models for location, shape and scale (GAMLSS) were applied to create percentile curves and evaluate goodness of fit, and the speed-accuracy trade-off was investigated.

RESULTS

26,633 subjects, including 13,771 (51.71%) men participated in this study. Age- and education-specific percentiles of the metrics were generated. Q tests and worm plots indicated adequate fit for models of MTx-RT and MTx-Cp. Models of MTx-%C for the low and intermediate education fit acceptably, but not well enough for a high level of education. A significant speed-accuracy trade-off was observed for MTx-%C from 72 to 94.

CONCLUSIONS

GAMLSS is a reliable method to generate smoothed age- and education-specific percentile curves of MTx metrics, which may be adopted for mass screening and follow-ups addressing Alzheimer's disease or other cognitive diseases.

HIGHLIGHTS

GAMLSS was applied to establish nonlinear percentile curves of cognitive decline. Subjects with a high level of education demonstrate a later onset and slower decline of cognition. Speed-accuracy trade-off effects were observed in a subgroup with moderate accuracy. MemTrax can be used as a mass-screen instrument for active cognition health management advice.

Non-Genetic Risk Factors of Alzheimer's Disease: An Updated Umbrella Review

BACKGROUND

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by intricate genetic and environmental etiology. The objective of this study was to identify robust non-genetic risk factors for AD through an updated umbrella review.

METHODS

We conducted a comprehensive search of meta-analyses and systematic reviews on non-genetic risk factors associated with AD in PubMed, Cochrane, Embase, and Ovid Medline up to June 30, 2023. After collecting data, we estimated the summary effect size and their 95% confidence intervals. The degree of heterogeneity between studies was assessed using I2 statistics and a 95% prediction interval was determined. Additionally, we evaluated potential excess significant bias and small study effects within the selected candidate studies.

RESULTS

The umbrella review encompassed a total of 53 eligible papers, which included 84 meta-analyses covering various factors such as lifestyle, diet, environmental exposures, comorbidity or infections, drugs, and biomarkers. Based on the evidence classification criteria employed in this study, two factors as convincing evidence (Class I), including rheumatoid arthritis (RA), potentially reduced the risk of AD, but diabetes significantly increased the risk of AD. Furthermore, three factors as highly suggestive evidence (Class II), namely depression, high homocysteine, and low folic acid level, potentially increased the risk of AD.

CONCLUSION

Our findings highlight several risk factors associated with AD that warrant consideration as potential targets for intervention. However, it is crucial to prioritize the identified modifiable risk factors, namely rheumatoid arthritis, diabetes, depression, elevated homocysteine levels, and low folic acid levels to effectively address this complex neurodegenerative disorder.

Artificial intelligence for dementia genetics and omics

Genetics and omics studies of Alzheimer's disease and other dementia subtypes enhance our understanding of underlying mechanisms and pathways that can be targeted. We identified key remaining challenges: First, can we enhance genetic studies to address missing heritability? Can we identify reproducible omics signatures that differentiate between dementia subtypes? Can high-dimensional omics data identify improved biomarkers? How can genetics inform our understanding of causal status of dementia risk factors? And which biological processes are altered by dementia-related genetic variation? Artificial intelligence (AI) and machine learning approaches give us powerful new tools in helping us to tackle these challenges, and we review possible solutions and examples of best practice. However, their limitations also need to be considered, as well as the need for coordinated multidisciplinary research and diverse deeply phenotyped cohorts. Ultimately AI approaches improve our ability to interrogate genetics and omics data for precision dementia medicine. HIGHLIGHTS: We have identified five key challenges in dementia genetics and omics studies. AI can enable detection of undiscovered patterns in dementia genetics and omics data. Enhanced and more diverse genetics and omics datasets are still needed. Multidisciplinary collaborative efforts using AI can boost dementia research.

Community-Based Strategies to Reduce Alzheimer's Disease and Related Dementia Incidence Among Rural, Racially/Ethnically Diverse Older Adults

Purpose of Review

The purpose of this paper was to address the research question "What recent advances in Alzheimer's Disease and Related Dementias (ADRD) risk reduction strategies can be tailored for rural, racially/ethnically diverse populations?" A rural resident's life story that grounded the work is shared. Next, a brief description is provided regarding ADRD risk factors of importance in rural, multicultural settings. Gaps in U.S.-based research are highlighted. Policy actions and interventions that may make a difference in alleviating rural, ADRD-related disparities are offered.

Recent Findings

More than a dozen factors, including lack of built environment, periodontitis, poor air quality, and sensory loss, were identified that are of particular relevance to rural groups. Evidence of importance to underserved residents has also emerged regarding the harmful effects of ultra-processed foods on brain health, benefits of even minimal physical activity, and importance of social engagement, on brain health.

Summary

Resident-led initiatives will be key to creating change at the community level. Health providers are also called to assist in identifying and adapting culturally specific upstream approaches, in partnership with community stakeholders. These mechanisms are vital for decreasing ADRD burdens in underserved communities facing the largest disparities in preventive care.

Association of biological age with health outcomes and its modifiable factors

Identifying the clinical implications and modifiable and unmodifiable factors of aging requires the measurement of biological age (BA) and age gap. Leveraging the biomedical traits involved with physical measures, biochemical assays, genomic data, and cognitive functions from the healthy participants in the UK Biobank, we establish an integrative BA model consisting of multi-dimensional indicators. Accelerated aging (age gap >3.2 years) at baseline is associated incident circulatory diseases, related chronic disorders, all-cause, and cause-specific mortality. We identify 35 modifiable factors for age gap (p < 4.81 × 10-4 ), where pulmonary functions, body mass, hand grip strength, basal metabolic rate, estimated glomerular filtration rate, and C-reactive protein show the most significant associations. Genetic analyses replicate the possible associations between age gap and health-related outcomes and further identify CST3 as an essential gene for biological aging, which is highly expressed in the brain and is associated with immune and metabolic traits. Our study profiles the landscape of biological aging and provides insights into the preventive strategies and therapeutic targets for aging.

Critical thinking of Alzheimer's transgenic mouse model: current research and future perspective

Transgenic models are useful tools for studying the pathogenesis of and drug development for Alzheimer's Disease (AD). AD models are constructed usually using overexpression or knock-in of multiple pathogenic gene mutations from familial AD. Each transgenic model has its unique behavioral and pathological features. This review summarizes the research progress of transgenic mouse models, and their progress in the unique mechanism of amyloid-β oligomers, including the first transgenic mouse model built in China based on a single gene mutation (PSEN1 V97L) found in Chinese familial AD. We further summarized the preclinical findings of drugs using the models, and their future application in exploring the upstream mechanisms and multitarget drug development in AD.