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Age and Ageing Jun 2024Epigenetic ageing is among the most promising ageing biomarkers and may be a useful marker of physical function decline, beyond chronological age. This study...
BACKGROUND
Epigenetic ageing is among the most promising ageing biomarkers and may be a useful marker of physical function decline, beyond chronological age. This study investigated whether epigenetic age acceleration (AA) is associated with the change in frailty scores over 7 years and the 7-year risk of incident frailty and persistent Activities of Daily Living (ADL) disability among 560 Australians (50.7% females) aged ≥70 years.
METHODS
Seven AA indices, including GrimAge, GrimAge2, FitAge and DunedinPACE, were estimated from baseline peripheral-blood DNA-methylation. Frailty was assessed using both the 67-item deficit-accumulation frailty index (FI) and Fried phenotype (Fried). Persistent ADL disability was defined as loss of ability to perform one or more basic ADLs for at least 6 months. Linear mixed models and Cox proportional-hazard regression models were used as appropriate.
RESULTS
Accelerated GrimAge, GrimAge2, FitAge and DunedinPACE at baseline were associated with increasing FI scores per year (adjusted-Beta ranged from 0.0015 to 0.0021, P < 0.05), and accelerated GrimAge and GrimAge2 were associated with an increased risk of incident FI-defined frailty (adjusted-HRs 1.43 and 1.39, respectively, P < 0.05). The association between DunedinPACE and the change in FI scores was stronger in females (adjusted-Beta 0.0029, P 0.001 than in males (adjusted-Beta 0.0002, P 0.81). DunedinPACE, but not the other AA measures, was also associated with worsening Fried scores (adjusted-Beta 0.0175, P 0.04). No associations were observed with persistent ADL disability.
CONCLUSION
Epigenetic AA in later life is associated with increasing frailty scores per year and the risk of incident FI-defined frailty.
Topics: Humans; Female; Activities of Daily Living; Male; Aged; Frailty; Frail Elderly; Epigenesis, Genetic; Geriatric Assessment; Aging; Risk Factors; Aged, 80 and over; Disability Evaluation; DNA Methylation; Age Factors; Risk Assessment; Time Factors; Functional Status
PubMed: 38941117
DOI: 10.1093/ageing/afae127 -
JAMA Network Open Jun 2024Although existing research has found daily heat to be associated with dementia-related outcomes, there is still a gap in understanding the differing associations of...
IMPORTANCE
Although existing research has found daily heat to be associated with dementia-related outcomes, there is still a gap in understanding the differing associations of nighttime and daytime heat with dementia-related deaths.
OBJECTIVES
To quantitatively assess the risk and burden of dementia-related deaths associated with short-term nighttime and daytime heat exposure and identify potential effect modifications.
DESIGN, SETTING, AND PARTICIPANTS
This case-crossover study analyzed individual death records for dementia across all mainland China counties from January 1, 2013, to December 31, 2019, using a time-stratified case-crossover approach. Statistical analysis was conducted from January 1, 2013, to December 31, 2019.
EXPOSURES
Two novel heat metrics: hot night excess (HNE) and hot day excess (HDE), representing nighttime and daytime heat intensity, respectively.
MAIN OUTCOMES AND MEASURES
Main outcomes were the relative risk and burden of dementia-related deaths associated with HNE and HDE under different definitions. Analysis was conducted with conditional logistic regression integrated with the distributed lag nonlinear model.
RESULTS
The study involved 132 573 dementia-related deaths (mean [SD] age, 82.5 [22.5] years; 73 086 women [55.1%]). For a 95% threshold, the median hot night threshold was 24.5 °C (IQR, 20.1 °C-26.2 °C) with an HNE of 3.7 °C (IQR, 3.1 °C-4.3 °C), and the median hot day threshold was 33.3 °C (IQR, 29.9 °C-34.7 °C) with an HDE of 0.6 °C (IQR, 0.5 °C-0.8 °C). Both nighttime and daytime heat were associated with increased risk of dementia-related deaths. Hot nights' associations with risk of dementia-related deaths persisted for 6 days, while hot days' associations with risk of dementia-related deaths extended over 10 days. Extreme HDE had a higher relative risk of dementia-related deaths, with a greater burden associated with extreme HNE at more stringent thresholds. At a 97.5% threshold, the odds ratio for dementia-related deaths was 1.38 (95% CI, 1.22-1.55) for extreme HNE and 1.46 (95% CI, 1.27-1.68) for extreme HDE, with an attributable fraction of 1.45% (95% empirical confidence interval [95% eCI], 1.43%-1.47%) for extreme HNE and 1.10% (95% eCI, 1.08%-1.11%) for extreme HDE. Subgroup analyses suggested heightened susceptibility among females, individuals older than 75 years of age, and those with lower educational levels. Regional disparities were observed, with individuals in the south exhibiting greater sensitivity to nighttime heat and those in the north to daytime heat.
CONCLUSIONS AND RELEVANCE
Results of this nationwide case-crossover study suggest that both nighttime and daytime heat are associated with increased risk of dementia-related deaths, with a greater burden associated with nighttime heat. These findings underscore the necessity of time-specific interventions to mitigate extreme heat risk.
Topics: Humans; China; Dementia; Female; Male; Aged; Aged, 80 and over; Hot Temperature; Cross-Over Studies; Risk Factors
PubMed: 38941091
DOI: 10.1001/jamanetworkopen.2024.19250 -
Bioinformatics (Oxford, England) Jun 2024Electronic health records (EHRs) represent a comprehensive resource of a patient's medical history. EHRs are essential for utilizing advanced technologies such as deep...
MOTIVATION
Electronic health records (EHRs) represent a comprehensive resource of a patient's medical history. EHRs are essential for utilizing advanced technologies such as deep learning (DL), enabling healthcare providers to analyze extensive data, extract valuable insights, and make precise and data-driven clinical decisions. DL methods such as recurrent neural networks (RNN) have been utilized to analyze EHR to model disease progression and predict diagnosis. However, these methods do not address some inherent irregularities in EHR data such as irregular time intervals between clinical visits. Furthermore, most DL models are not interpretable. In this study, we propose two interpretable DL architectures based on RNN, namely time-aware RNN (TA-RNN) and TA-RNN-autoencoder (TA-RNN-AE) to predict patient's clinical outcome in EHR at the next visit and multiple visits ahead, respectively. To mitigate the impact of irregular time intervals, we propose incorporating time embedding of the elapsed times between visits. For interpretability, we propose employing a dual-level attention mechanism that operates between visits and features within each visit.
RESULTS
The results of the experiments conducted on Alzheimer's Disease Neuroimaging Initiative (ADNI) and National Alzheimer's Coordinating Center (NACC) datasets indicated the superior performance of proposed models for predicting Alzheimer's Disease (AD) compared to state-of-the-art and baseline approaches based on F2 and sensitivity. Additionally, TA-RNN showed superior performance on the Medical Information Mart for Intensive Care (MIMIC-III) dataset for mortality prediction. In our ablation study, we observed enhanced predictive performance by incorporating time embedding and attention mechanisms. Finally, investigating attention weights helped identify influential visits and features in predictions.
AVAILABILITY AND IMPLEMENTATION
https://github.com/bozdaglab/TA-RNN.
Topics: Electronic Health Records; Neural Networks, Computer; Humans; Deep Learning; Alzheimer Disease
PubMed: 38940180
DOI: 10.1093/bioinformatics/btae264 -
Frontiers in Bioscience (Landmark... Jun 2024
Topics: Humans; Biomarkers; Dementia; Proteostasis Deficiencies; Protein Folding; Alzheimer Disease
PubMed: 38940055
DOI: 10.31083/j.fbl2906227 -
Frontiers in Bioscience (Landmark... Jun 2024Alzheimer's disease is characterized by extracellular beta-amyloid plaques, intraneuronal tau neurofibrillary tangles and excessive neurodegeneration. The mechanisms of...
BACKGROUND
Alzheimer's disease is characterized by extracellular beta-amyloid plaques, intraneuronal tau neurofibrillary tangles and excessive neurodegeneration. The mechanisms of neuron degeneration and the potential of these neurons to form new nerve fibers for compensation remain elusive. The present study aimed to evaluate the impact of beta-amyloid and tau on new formations of nerve fibers from mouse organotypic brain slices connected to collagen-based microcontact prints.
METHODS
Organotypic brain slices of postnatal day 8-10 wild-type mice were connected to established collagen-based microcontact prints loaded with polyornithine to enhance nerve fiber outgrowth. Human beta-amyloid(42) or P301S mutated aggregated tau was co-loaded to the prints. Nerve fibers were immunohistochemically stained with neurofilament antibodies. The physiological activity of outgrown neurites was tested with neurotracer MiniRuby, voltage-sensitive dye FluoVolt, and calcium-sensitive dye Rhod-4.
RESULTS
Immunohistochemical staining revealed newly formed nerve fibers extending along the prints derived from the brain slices. While collagen-only microcontact prints stimulated nerve fiber growth, those loaded with polyornithine significantly enhanced nerve fiber outgrowth. Beta-amyloid(42) significantly increased the neurofilament-positive nerve fibers, while tau had only a weak effect. MiniRuby crystals, retrogradely transported along these newly formed nerve fibers, reached the hippocampus, while FluoVolt and Rhod-4 monitored electrical activity in newly formed nerve fibers.
CONCLUSIONS
Our data provide evidence that intact nerve fibers can form along collagen-based microcontact prints from mouse brain slices. The Alzheimer's peptide beta-amyloid(42) stimulates this growth, hinting at a neuroprotective function when physiologically active. This "brain-on-chip" model may offer a platform for screening bioactive factors or testing drug effects on nerve fiber growth.
Topics: Animals; Amyloid beta-Peptides; Mice; Nerve Fibers; Brain; tau Proteins; Humans; Immunohistochemistry; Peptide Fragments; Alzheimer Disease; Mice, Inbred C57BL
PubMed: 38940051
DOI: 10.31083/j.fbl2906232 -
Annals of Clinical and Translational... Jun 2024Amyloid-related imaging abnormalities, were originally described by dementia care experts. The wider use of aducanumab and now lecanemab warrant broader understanding by... (Review)
Review
Amyloid-related imaging abnormalities, were originally described by dementia care experts. The wider use of aducanumab and now lecanemab warrant broader understanding by the health care provider continuum. The optimal care approach for patients with Alzheimer's dementia, treated with amyloid-targeted therapy, includes proper clinical diagnosis, complication surveillance, specific imaging protocols, expert specialty consultation, integrated treatment strategies, and proper facility system planning. Improved awareness and understanding of amyloid-modifying therapy, both benefits and potential complications, among the health care provider continuum is paramount to the success of complex care programs. Specifically, recognition of treatment high risk, high benefit groups, and the interface of concurrent antiplatelet and anticoagulation. This integrated acute, specialty, and primary care approach should improve patient care quality and outcome.
PubMed: 38939962
DOI: 10.1002/acn3.52042 -
Sheng Li Xue Bao : [Acta Physiologica... Jun 2024The purpose of the study was to investigate the mechanism of TFEB activator 1 (TA1) improving the autophagic degradation of oligomeric amyloid-β (oAβ) in microglia,...
The purpose of the study was to investigate the mechanism of TFEB activator 1 (TA1) improving the autophagic degradation of oligomeric amyloid-β (oAβ) in microglia, and to explore the therapeutic effect of TA1 on an in vitro model of microglia in Alzheimer's disease (AD). Primary microglia were exposed to 1 μmol/L oAβ for 0, 3, 12, and 24 h respectively to construct the in vitro model of microglia in AD. In order to explore the therapeutic effect of TA1, primary microglia were co-treated with 1 μmol/L oAβ and 1 μmol/L TA1 for 12 h. To determine the autophagy flux, the above cells were further treated with 100 nmol/L Bafilomycin A1 for 1 h before fixation. Fluorescent probes were used to detect the endocytosis or degradation of oAβ by microglia. The autophagic flux was determined by infection of lentivirus mCherry-EGFP-LC3. The nuclear TFEB intensity, the autophagosomes number, and the colocalization ratio of oAβ with lysosome-associated membrane protein 1 (LAMP1) or microtubule-associated protein light chain 3 (LC3), were detected by immunofluorescence assay. Expressions of autophagy-related-genes, including Lamp1, Atg5, and Map1lc3b, were detected by qRT-PCR. Results showed that prolonged oAβ exposure inhibited the endocytosis and degradation of oAβ by microglia. Meanwhile, the number of autophagosomes and autophagy flux in microglia decreased after 12 h of oAβ treatment. We further found that the nuclear expression of autophagy regulator TFEB decreased after 12 h of oAβ exposure, resulting in the decrease of autophagy genes, thus leading to the damage of autophagic degradation of oAβ. Therefore, long-term oAβ exposure was considered to construct the in vitro model of microglia in AD. After TA1 treatment, the nuclear expression of TFEB in cells was obviously upregulated. TA1 treatment upregulated the expressions of autophagy-related genes, leading to the recovery of autophagy flux. TA1 also recovered the endocytosis and degradation of oAβ by microglia. In conclusion, TA1 could improve oAβ clearance by microglia in AD by upregulating microglial TFEB-mediated autophagy, suggesting TA1 as a potential therapeutic drug for AD.
Topics: Microglia; Amyloid beta-Peptides; Autophagy; Animals; Basic Helix-Loop-Helix Leucine Zipper Transcription Factors; Alzheimer Disease; Cells, Cultured; Mice
PubMed: 38939931
DOI: No ID Found -
Annals of Ibadan Postgraduate Medicine Apr 2024Knowledge on the clinical presentation of dementia is essential for appropriate care, especially in Low-and-Middle-Income Countries where these cases are on a sharp rise...
BACKGROUND
Knowledge on the clinical presentation of dementia is essential for appropriate care, especially in Low-and-Middle-Income Countries where these cases are on a sharp rise and can also aid early detection of other underlying conditions.This study sought to provide a broad and updated socio-demographic, clinical profile, pattern of diagnosis and treatment features of people diagnosed with dementia in this setting.
METHOD
A retrospective cohort study which reviewed the medical case records of all older adults with dementia receiving treatment at the psychogeriatric and the neurology clinic of the Geriatric Centre (N=192). A proforma was designed to collect information from the case records.
RESULTS
The mean (±SD) age of the participants was 74.0(±7.2) years, 97.9% lived with other persons, 50.0% had at least one comorbidity and 52.6% presented late for treatment. Overall, hypertension (64.1%) and diabetes (22.4%) were the most common comorbidity, 55.2% had complaints bordering on behavioural problems; irrational speech (31.3%) being the most common, while 91.7% had forgetfulness as a cognitive symptom.
CONCLUSION
A high rate of comorbidities, as well as late presentation was common among the participants. Our findings appraise the clinical importance of detailed knowledge of the patterns and profiles of older adults with dementia for early presentation and treatment.
PubMed: 38939888
DOI: No ID Found -
Journal of Arrhythmia Jun 2024Recent evidence suggests an elevated risk of cognitive impairment and dementia in individuals with atrial fibrillation (AF), irrespective of stroke occurrence. AF, known... (Review)
Review
BACKGROUND
Recent evidence suggests an elevated risk of cognitive impairment and dementia in individuals with atrial fibrillation (AF), irrespective of stroke occurrence. AF, known to reduce brain perfusion, particularly through silent cerebral ischemia, underscores the intricate relationship between cardiac and cerebral health. The heart plays a crucial role in supporting normal brain function, and rhythm control, a standard AF treatment, has demonstrated enhancements in brain perfusion. This systematic review aimed to examine published data concerning the influence of rhythm control on brain perfusion in patients with atrial fibrillation.
METHODS
A systematic search for relevant studies was carried out in Scopus, PubMed, Cochrane Reviews, ProQuest, and EBSCOhost, spanning from their inception until April 30, 2023. Studies that specifically examined brain perfusion following any form of rhythm control in atrial fibrillation were included in the review.
RESULTS
The review encompassed 10 studies involving 436 participants. Among these, six utilized electrical cardioversion for rhythm control. The majority (8 out of 10) demonstrated that restoring sinus rhythm markedly enhances brain perfusion. In one of the two remaining studies, notable improvement was observed specifically in a region closely linked to cognition. Additionally, both studies reporting data on the Mini-Mental State Examination (MMSE) showed a consistent and significant increase in scores following rhythm control.
CONCLUSION
Successful rhythm control in AF emerges as a significant contributor to enhanced brain perfusion, suggesting a potential therapeutic avenue for reducing cognitive impairment incidence. However, further validation through larger prospective studies and randomized trials is warranted.
PubMed: 38939785
DOI: 10.1002/joa3.13056 -
Frontiers in Global Women's Health 2024Evidence suggests that a combination of biological and social factors influence risk of dementia differently for women and men. In healthy older women, several factors...
BACKGROUND
Evidence suggests that a combination of biological and social factors influence risk of dementia differently for women and men. In healthy older women, several factors may contribute to changes in cognition.
OBJECTIVE
Describe the characteristics associated with variation in cognition in a sample of cognitively healthy older Panamanian women.
METHODS
The study includes cross-sectional analyses of cognitive domains at baseline (= 357) and 17-month (SD = 2.0) follow-up (= 200) for women aged 60 years and older enrolled in the Panama Aging Research Initiative-Health Disparities (PARI-HD) study. Instruments included clinical questionnaires, physiological measures, and a neuropsychological test battery assessing global cognition and seven cognitive domains. Multiple regression analyses examined the associations between demographic and clinical characteristics and cognition at baseline. Repeated measures analyses were used to investigate changes in cognition from baseline to follow-up.
RESULTS
On average, participants were 68.6 years of age (SD = 5.9) with 16.1 years of education (SD = 4.7). Age, income, and education showed robust associations with baseline cognition. Subjective cognitive impairment was associated with lower performance in global cognition, verbal learning, and memory domains. Only performance in the attention domain decreased at follow-up, and subjective health state and depressive symptoms significantly predicted the change in attention.
DISCUSSION
Our study findings contribute to the investigation of cognitive health in older Hispanic women and to the understanding of sociodemographic and health-related factors associated with cognitive decline and the progression to cognitive impairment and dementia.
PubMed: 38939750
DOI: 10.3389/fgwh.2024.1353657