Dementia and Geriatric Cognitive Disorders最新文献

Introduction: Both physical and cognitive functions are required to be assessed to determine the level of gait independence in patients with Alzheimer's disease (AD); nonetheless, a method to achieve this assessment has not been established. This study aimed to investigate the accuracy of an assessment method that combined muscle strength, balance ability, and cognitive function parameters in discriminating the level of gait independence in a real-world setting in hospitalized patients with AD.

Methods: In this cross-sectional study, 63 patients with AD (mean age: 86.1 ± 5.8 years) were classified into three groups according to their gait level: independent, modified independent (independent walking with walking aids), and dependent groups. Discrimination accuracy was calculated for single items of muscle strength, balance ability, and cognitive function tests and for combinations of each.

Results: The combined accuracy of muscle strength, balance ability, and cognitive function had a positive predictive value of 100.0% and a negative predictive value of 67.7% between the independent and modified independent groups. The positive and negative predictive values were 100.0% and 72.4%, respectively, between the modified independent and dependent groups.

Conclusion: This study emphasizes the importance of assessing the level of gait independence in a real-world setting in patients with AD from the perspective of both physical and cognitive functions and proposes a novel method for discriminating an optimal state.

Introduction: Identifying health conditions of persons with cognitive impairment (PCI) in the community and exploring their implications for caregiving experience are vital for effective allocation of healthcare resources. This study examined distinct PCI health profiles among community-dwelling PCI and their association with caregiving burden and benefits.

Methods: Latent profile analysis and multivariable regression were applied to dyadic data from 266 PCI and their caregivers in Singapore.

Results: Three PCI health profiles were identified: less impaired (40% of PCI), moderately impaired (30%), and severely impaired (30%). Caregivers for severely impaired PCI were more likely to report a higher level of caregiving burden, and caregivers for moderately impaired PCI were more likely to report a higher level of caregiving benefits, compared to caregivers for less impaired PCI.

Conclusion: The findings captured heterogeneity in health status among PCI in the community. Tailored interventions, based on PCI health profiles, should be designed to reduce caregiving burden and increase caregiving benefits.

Introduction: Vascular factors have been shown to be associated with increased risk of dementia. However, clinical trials have so far been unsuccessful, suggesting new approaches are needed. The aim of this study was to use population-based real-world data to investigate risk factors and preventive factors for dementia, including the effects of traditional Chinese medicine (TCM).

Methods: This is a retrospective cohort study using LHID2000, a dataset randomly selected from Taiwan's National Health Insurance Research Database. Subjects with occlusion and stenosis of precerebral and cerebral arteries, cerebral atherosclerosis without mention of cerebral infarction, and transient cerebral ischemia were included. Subjects with dementia at baseline were excluded. The primary endpoint was dementia. Data for demographic and clinical comorbid status and treatments administered at baseline in 2000 and at the end of follow-up in 2013 were included.

Results: A total of 4,207 subjects with cerebral vascular disease and no cognitive impairment were included, of whom 392 converted to dementia during an average 5.15-year (SD: 3.79) follow-up. Depression (adjusted HR: 1.54, 95% confidence interval [CI]: 1.13-2.09), osteoporosis (adjusted HR: 1.34, 95% CI: 1.04-1.74), and the use of enalapril (adjusted HR: 1.37, 95% CI: 1.09-1.73) were risk factors for dementia, while nitroglycerin (adjusted HR: 0.67, 95% CI: 0.53-0.85) was a protecting factor, in subjects with cerebrovascular diseases without mention of cerebral infarction. In total, statins were shown to be associated with decreased risk of dementia (HR: 0.73, 95% CI: 0.59-0.91); however, no one statin subtype or TCM had such an effect.

Conclusion: Depression, osteoporosis, and the use of enalapril were associated with a higher risk of dementia, while nitroglycerin might be a protecting factor for dementia, in subjects with cerebrovascular diseases without mention of cerebral infarction.

Introduction: Sensorineural hearing loss is a common problem, especially among geriatric patients, and it requires hearing aids. Unfortunately, most geriatric patients are hesitant to use hearing aids. The purpose of this study was to investigate whether computerized training therapies increase the attention and perception of patients who have been given hearing aids using psychophysiological tests and wave P300 records.

Methods: One hundred patients (40 women and 60 men) who used hearing aids were included in our study. Sixty patients (30 women and 30 men) received computerized training therapies with hearing aids. After the psychophysiological tests, the study group was divided into three groups according to the role given to patients. Passive training was given in group 1; interactive training was given in group 2; and group 3 was active, questioning training. Measurements of P300 wave latencies, stimuli-P300 peak, and baseline-P300 peak were performed before and after training. The control group consisted of 40 patients who did not receive training and were treated with hearing aids only.

Results: We found a significant difference between the pre- and post-training measures of the P300 wave (p < 0.001). Pre-training measurements of P300 waves were recorded for 12% in group 1 and 9.1% in groups 2 and 3 (p = 0.24). Post-training measurements of the P300 wave records were 80% in group 1 and 72.7% in groups 2 and 3 (p = 0.22).

Conclusion: Attention and perception can be measured with the P300 wave. All computer-supported training programs showed an increase of the P300 wave, suggesting that attention and perception of patients with hearing loss can be increased with computer-supported training programs provided with hearing aids.

Introduction: As disease-modifying therapies become available for Alzheimer's disease (AD), detection of AD in early stages of illness (mild cognitive impairment [MCI], early dementia) becomes increasingly important. Biomarkers for AD in low- and middle-income countries (LMICs) are costly and not widely available; hence, it is important to identify cognitive tests that correlate well with AD biomarker status. In this study, we evaluated the memory alteration test (M@T) to detect biomarker-proven AD and quantify its correlation with neurodegeneration and cerebrospinal fluid (CSF) AD biomarkers in a cohort of participants from Lima, Peru.

Methods: This is a secondary analysis of a cohort of 185 participants: 63 controls, 53 with amnestic MCI (aMCI), and 69 with dementia due to AD. Participants underwent testing with M@T and a gold standard neuropsychological battery. We measured total tau (t-tau), phosphorylated tau (p-tau), and beta-amyloid (β-amyloid) in CSF, and evaluated neurodegeneration via medial temporal atrophy score in MRI. We used receiver-operator curves to determine the discriminative capacity of the total M@T score and its subdomains. We used the Pearson coefficient to correlate M@T score and CSF biomarkers.

Results: The M@T had an area under the curve (AUC) of 0.994 to discriminate between controls and cognitively impaired (aMCI or AD) patients, and an AUC of 0.98 to differentiate between aMCI and AD patients. Free-recall and cued recall had the highest AUCs of all subdomains. Total score was strongly correlated with t-tau (-0.77) and p-tau (-0.72), and moderately correlated with β-amyloid (0.66). The AUC for discrimination of neurodegeneration was 0.87.

Conclusion: The M@T had excellent discrimination of aMCI and dementia due to AD. It was strongly correlated with CSF biomarkers and had good discrimination of neurodegeneration. In LMICs, the M@T may be a cost-effective screening tool for aMCI and dementia caused by AD.

Introduction: Carnosine can suppress secondary complications in diabetes and show robust neuroprotective activity against neurodegenerative diseases. Here, we report that carnosine ameliorates diabetes-associated cognitive decline in vivo through the modulation of autophagy.

Methods: A high-fat diet (HFD) and one intraperitoneal injection of 30 mg/kg streptozotocin (STZ) were used to induce type 2 diabetes mellitus in Sprague-Dawley rats. The rats were randomly divided into five groups: control (CON), HFD/STZ, and three intragastric carnosine treatment groups receiving low (100 mg/kg), medium (300 mg/kg), and high (900 mg/kg) doses over 12 weeks. Body weight, blood glucose levels, and cognitive function were continuously monitored. From excised rat hippocampi, we determined superoxide dismutase (SOD) activity and malondialdehyde (MDA) levels; carnosine concentration; protein expressions of Akt, mTOR and the autophagy markers LC3B and P62 and performed histopathological evaluations of the cornu ammonis 1 region.

Results: The HFD/STZ group showed increased blood glucose levels and decreased body weight compared to the CON group. However, there were no significant differences in body weight and blood glucose levels between carnosine-treated and -untreated HFD-STZ-induced diabetic rats. Diabetic animals showed obvious learning and memory impairments in the Morris water maze test compared to the CON group. Compared to those in the HFD/STZ group, carnosine increased SOD activity and decreased MDA levels, increased hippocampal carnosine concentration, increased p-Akt and p-mTOR expression, decreased LC3B and P62 expression, alleviated neuronal injuries, and improved cognitive performance in a dose-dependent manner.

Conclusion: Independent of any hyperglycemic effect, carnosine may improve mild cognitive impairments by mitigating oxidative stress, activating the Akt/mTOR pathway, and modulating autophagy in the hippocampus of type 2 diabetic rats.

Introduction: Early-life educational attainment contributes to cognitive reserve (CR). We investigated the associations of lifelong CR with dementia and mild cognitive impairment (MCI) among older people with limited formal education.

Methods: This population-based cohort study included 2,127 dementia-free participants (≥60 years; 59.4% women; 81.5% with no or elementary school) who were examined at baseline (August-December 2014) and follow-up (March-September 2018). Lifelong CR score at baseline was generated from six lifespan intellectual factors. Dementia, MCI, and their subtypes were defined according to the international criteria. Data were analyzed using Cox proportional-hazards models.

Results: During the total of 8,330.6 person-years of follow-up, 101 persons were diagnosed with dementia, including 74 with Alzheimer's disease (AD) and 26 with vascular dementia (VaD). The high (vs. low) tertile of lifelong CR score was associated with multivariable-adjusted hazards ratios (95% confidence interval) of 0.28 (0.14-0.55) for dementia and 0.18 (0.07-0.48) for AD. The association between higher CR and reduced AD risk was significant in people aged 60-74 but not in those aged ≥75 years (p for interaction = 0.011). Similarly, among MCI-free people at baseline (n = 1,635), the high (vs. low) tertile of lifelong CR score was associated with multivariable-adjusted hazard ratios of 0.51 (0.38-0.69) for MCI and 0.46 (0.33-0.64) for amnestic MCI. Lifelong CR was not related to VaD or non-amnestic MCI.

Discussion: High lifelong CR is associated with reduced risks of dementia and MCI, especially AD and amnestic MCI. It highlights the importance of lifelong CR in maintaining late-life cognitive health even among people with no or limited education.

Introduction: This study aimed to develop novel machine learning models for predicting Alzheimer's disease (AD) and identify key factors for targeted prevention.

Methods: We included 1,219, 863, and 482 participants aged 60+ years with only sociodemographic, both sociodemographic and self-reported health, both the former two and blood biomarkers information from Alzheimer's Disease Neuroimaging Initiative (ADNI) database. Machine learning models were constructed for predicting the risk of AD for the above three populations. Model performance was evaluated by discrimination, calibration, and clinical usefulness. SHapley Additive exPlanation (SHAP) was applied to identify key predictors of optimal models.

Results: The mean age was 73.49, 74.52, and 74.29 years for the three populations, respectively. Models with sociodemographic information and models with both sociodemographic and self-reported health information showed modest performance. For models with sociodemographic, self-reported health, and blood biomarker information, their overall performance improved substantially, specifically, logistic regression performed best, with an AUC value of 0.818. Blood biomarkers of ptau protein and plasma neurofilament light, age, blood tau protein, and education level were top five significant predictors. In addition, taurine, inosine, xanthine, marital status, and L.Glutamine also showed importance to AD prediction.

Conclusion: Interpretable machine learning showed promise in screening high-risk AD individual and could further identify key predictors for targeted prevention.

Introduction: Transcranial Doppler (TCD) sonography is a noninvasive tool for measuring cerebrovascular hemodynamics. Studies have reported alterations in cerebrovascular hemodynamics in normal aging, mild cognitive impairment (MCI), and dementia, as well as in different etiologies of dementia. This systematic review and meta-analysis was designed to investigate the relationship between cerebral blood velocity (CBv) and pulsatility index (PI) in the middle cerebral artery (MCA) in persons with MCI and dementia.

Methods: A systematic literature search was conducted in Pubmed, Embase, Cochrane Library, Epistemonikos, PsychINFO, and CINAHL. The search was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. After screening of 33,439 articles, 86 were reviewed in full-text, and 35 fulfilled the inclusion criteria.

Results: CBv was significantly lower and PI significantly higher in MCA in vascular dementia (VaD) and Alzheimer's disease (AD) compared to cognitively normal (CN) older persons. Also, CBv was lower in MCI compared to CN. There were no significant differences in CBv in MCA in AD compared with VaD, although PI was higher in VaD compared to AD.

Conclusion: Alterations in cerebrovascular hemodynamics are seen in AD, VaD, and MCI. While PI was slightly higher in VaD compared to AD, the reduction in CBv appears to be equally pronounced across neurodegenerative and vascular etiologies of dementia.