Coffee and tea consumption and dementia risk: The role of sex and vascular comorbidities

BACKGROUND

Coffee and tea consumption has been linked to dementia. However, it remained unknown how sex and vascular risk factors modify the association. We aimed to investigate the association of coffee and tea consumption with dementia and whether sex and vascular comorbidities modified the association.

METHODS

We included 278 elderly patients with Alzheimer's disease (AD) and 102 patients with vascular dementia (VaD) from three hospitals; controls (N = 468) were recruited during the same period. We collected the frequency and amount of coffee and tea consumption and the presence of vascular comorbidities. The multinomial logistic regression model was utilized to evaluate the association of coffee and tea consumption with dementia, stratified by sex and vascular comorbidities.

RESULTS

Different combinations and quantities of coffee and tea consumption protected against AD and VaD. Consumption of ≥3 cups of coffee or tea per day was protective against AD [adjusted odds ratio (aOR) = 0.42; 95% confidence interval (CI) = 0.22-0.78)] and VaD (aOR = 0.42; 95% CI = 0.19-0.94). Stratified analyses showed that the protective effects of a higher quantity of coffee and tea against AD were more pronounced among females and individuals with hypertension. Consumption of either coffee or tea was associated with a decreased risk of VaD among diabetic participants (aOR = 0.23; 95% CI = 0.06-0.98). Hyperlipidemia modified the association of coffee or tea consumption on the risk of AD and VaD (both Pinteraction < 0.01).

CONCLUSION

The risk of AD and VaD was lower with increased consumption of coffee and tea; the impact differed by sex and vascular comorbidities including hypertension, hyperlipidemia, and diabetes.

The association between retinal vascular fractal dimension and cognitive function in the community-dwelling older adults cohort TIGER

BACKGROUND/PURPOSE

The small retinal vessels reflect cerebral microcirculation and its fractal dimension (Df), representing the complexity of the retinal microcirculation. However, the connection between retinal circulation and cognitive function lacked consistent and longitudinal evidence. This study aimed to explore the association between retinal vascular complexity and cognitive impairment over time in non-demented community-dwelling older adults.

METHODS

This four-year prospective cohort study (2015-2019) is part of the ongoing Taiwan Initiative for Geriatric Epidemiological Research (TIGER, 2011 to present). Of the 434 older adults (age >65) recruited, 207 participants were included for analysis. The retinal vascular Df was assessed by baseline images from fundus photography (2015-2017). Global (Montreal Cognitive Assessment-Taiwanese version, MoCA-T) and domain-specific cognition were assessed at the baseline and 2-year follow-up (2017-2019). The multivariable linear regression models and generalized linear mixed models were used to evaluate the association of Df with cognitive decline/impairment over time.

RESULTS

Decreased left retinal vascular complexity was associated with poor attention performance (β = -0.40). As follow-up time increased, decreased vascular complexity was associated with poor memory performance (right: β = -0.25; left: β = -0.19), and decreased right vascular complexity was associated with poor attention performance (β = -0.18).

CONCLUSION

Low retinal vascular complexity of the right or left eye may be differentially associated with cognitive domains in community-dwelling older adults over two years. The retinal vascular Df of either eye may be served as a screening tool for detecting cognitive impairment in the preclinical phase of dementia.

Substantia nigra nigrosome-1 imaging correlates with the severity of motor symptoms in Parkinson's disease

BACKGROUND

Nigrosome-1 imaging has been used for assisting the diagnosis of Parkinson's disease (PD). We aimed to examine the diagnostic performance of loss of nigrosome-1 in PD and the correlation between the size of the nigrosome-1 and motor severity of PD.

METHODS

We included 237 patients with PD and 165 controls. The motor severity of PD was assessed with the Unified Parkinson's Disease Rating Scale (UPDRS) part III score and Hoehn-Yahr staging. The 3 or 1.5 Tesla susceptibility-weighted imaging combined with a deep-learning algorithm was applied for detecting the loss and the size of nigrosome-1. Clinical correlations and diagnostic performance of size of nigrosome-1 were also investigated.

RESULTS

The mean nigrosome-1 size was significantly smaller in PD patients than in controls (0.06 ± 0.07 cm² vs. 0.20 ± 0.05 cm², P < 0.001). The area under the receiver operating characteristic curve (AUC) of the established model showed 0.94 accuracy (95% confidence interval [CI]: 0.87, 1.01, P < 0.01) in differentiating between the PD and control groups. Moreover, the partial loss of nigrosome-1 detected with SWI had an AUC of 0.96 in discriminating early-stage PD from controls (95% CI: 0.88, 1.02, P < 0.001). After adjusting for age, sex, disease duration, and levodopa equivalent daily dose, the estimated size of nigrosome-1 was negatively associated with the UPDRS part III motor score (ρ = -0.433, P < 0.001), but not with Mini-Mental State Examination scores (ρ = 0.006, P = 0.894).

CONCLUSIONS

The extent of loss and the size of nigrosome-1 may potentially assist in the diagnosis of PD. Nigrosome-1 size reflects the motor severity of PD.

Association of subclinical depressive symptoms and sleep with cognition in the community-dwelling older adults

BACKGROUND

/Purpose: This study aimed to explore the association of subclinical depressive symptoms and sleep with cognition in community-dwelling Taiwanese older adults.

METHODS

This four-year prospective cohort study (2015-2019) included 379 participants aged 65 years or older from the annual senior health checkup program at National Taiwan University Hospital who were followed up two years later. Global and domain cognitive functions were assessed using validated neuropsychological tests. Depressive symptoms were evaluated using the Center for Epidemiologic Studies Depression (CES-D) Scale. Sleep quality was evaluated using the Pittsburg Sleep Quality Index (PSQI). Excessive daytime sleepiness was assessed using the Epworth Sleepiness Scale (ESS). Generalized linear mixed models were used to explore the associations of subclinical depressive symptoms and sleep variables with cognition, adjusting for important covariates. Stratification analyses were performed using the sleep variables.

RESULTS

Over time, depressive symptoms were associated with poor performance of memory (βˆ = 0.24, P = 0.04) and executive function (βˆ = -0.24, P = 0.03). Poor sleep quality (elevated PSQI score) was associated with poor memory performance (βˆ = -0.04 to -0.03, P < 0.05). Excessive daytime sleepiness (elevated ESS score) was associated with poor performance of memory (βˆ = -0.02, P < 0.05) and executive function (βˆ = -0.02, P = 0.001). At baseline, better sleep quality and no excessive daytime sleepiness were associated with better memory performance over time.

CONCLUSION

Subclinical depressive symptoms, worse sleep quality, and excessive daytime sleepiness were differentially associated with impairment of cognitive domains (mainly memory and executive function).

[Application value of image fusion technology in transcatheter aortic valve implantation]

Objective: To analysis the application value of image fusion technology in transcatheter aortic valve implantation (TAVI). Methods: A total of 35 patients underwent trans-femoral TAVI using the first-generation VENUS-A valve in Heart Center of Henan Provincial People's Hospital from January 2020 to May 2021 were analyzed retrospectively. Among them, there were 21 males and 14 females, aged from 64 to 81 years, with a mean (SD) of (71.37±5.66) years. They were divided into conventional group (n=22) and fusion group (n=13), according to whether image fusion technology was used during operation. The preoperative general data, intraoperative data, differences of postoperative renal function and residence time in intensive care unit (ICU) were analyzed and compared between the two groups. The postoperative echocardiography and 12 lead ECG were observed. Results: All 35 patients in this study were with severe aortic stenosis, of which, 10 patients were complicated with moderate to severe regurgitation. Compared with the conventional group, the intraoperative fusion group had fewer angiography times [3.0 (3.0, 4.0) vs 5.0 (5.0, 6.0)], X-ray absorbed dose [342.0 (44.5) mGy vs 388.4 (71.0) mGy], and contrast dosage [(73.5±10.5) ml vs (90.3±10.3) ml], and shorter rapid pacing time [(14.0±1.6) seconds vs (16.5±2.0) seconds] (all P<0.05). There was no significant differences in X-ray irradiation time, operation time, sizing of the pre-dilated balloon, valve implantation depth and other indicators (all P>0.05). There was no significant differences in ICU retention time and postoperative renal function (all P>0.05). Postoperative echocardiography showed that the function of aortic valve was good, with mild perivalvular leakage in 2 cases in the conventional group and 1 case in the fusion group; and one patient was implanted with permanent pacemaker after TAVI in the conventional group. Conclusion: Image fusion technology simplifies the TAVI process, shortens the ventricular pacing time and reduces the dosage of X-ray and contrast, and has certain clinical application value.

Grip Strength and Sarcopenia Predict 2-Year Cognitive Impairment in Community-Dwelling Older Adults

OBJECTIVES

Using the Asian Working Group for Sarcopenia (AWGS2019) and the European Working Group on Sarcopenia in Older People (EWGSOP2) criteria, this study examined associations of sarcopenia and its components with specific domains of cognitive impairment over time.

DESIGN

A prospective cohort study with a 2-year follow-up.

SETTING AND PARTICIPANTS

This study is part of the Taiwan Initiatives for Geriatric Epidemiological Research (TIGER), which recruited participants aged 65 years old who attended the senior health checkup program at National Taiwan University Hospital (NTUH).

METHODS

Grip strength was measured using a handgrip dynamometer. Walking speed (m/s) was measured as the time required to walk 8 feet. Muscle mass was measured by performing a bioelectrical impedance analysis. Global cognition (assessed using the Taiwanese version of the Montreal Cognitive Assessment) and 4 cognitive domains (memory, executive function, verbal fluency, and attention) were assessed over time. Associations of sarcopenia and its components with cognitive impairment were evaluated after stratification by sex using generalized linear mixed models adjusted for essential covariates for cognitive impairment.

RESULTS

Compared with robust women, those with severe sarcopenia were more likely to have a global cognitive impairment over time (β = -0.87, P = .03 based on AWGS2019 criteria and β = -1.07, P = .02 based on the EWGSOP2 criteria). Among men, low grip strength was associated with poor scores on measures of global cognition (β = -0.80, P = .03), executive function (β = -0.35, P = .001), verbal fluency (β = -0.31, P = .02), and attention (β = -0.34, P = .008) over time.

CONCLUSIONS AND IMPLICATIONS

Severe sarcopenia predicted global and specific domains of cognitive impairment in older adults. Poor grip strength predicted cognitive impairment in men but not in women. A screen for sarcopenia severity and low muscle strength may be used to identify the risk of cognitive impairment.

Multimorbid Patterns and Cognitive Performance in the Presence of Informative Dropout Among Community-Dwelling Taiwanese Older Adults

Background and Objectives

Longitudinal studies among older adults often feature elevated dropout rates and multiple chronic conditions. How Taiwanese multimorbid patterns relate to different cognitive domains remains unclear. This study aims to identify sex-specific multimorbid patterns and associate them with cognitive performance while modeling the risk for dropout.

Research Design and Methods

A prospective cohort study (2011-19) in Taiwan recruited 449 Taiwanese older adults without dementia. Global and domain-specific cognition were assessed biennially. We used exploratory factor analysis to identify baseline sex-specific multimorbid patterns of 19 self-reported chronic conditions. We utilized a joint model incorporating longitudinal and time-to-dropout data to examine the association between multimorbid patterns and cognitive performance accounting for the informative dropout via the shared random effect.

Results

At the end of the study, 324 participants (72.1%) remained in the cohort, with an average annual attrition rate of 5.5%. We found that advanced age, low levels of physical activities, and poor cognition at baseline were associated with increased dropout risks. Besides, 6 multimorbid patterns were identified, labeled Mental, Renal-vascular, and Cancer-urinary patterns in men, and Mental, Cardiometabolic, and Cancer-endocrine patterns in women. For men, as the follow-up time increased, the Mental pattern was associated with poor global cognition and attention; the Renal-vascular pattern was associated with poor executive function. For women, the Mental pattern was associated with poor memory; as follow-up time increased, and Cardiometabolic patterns were related to poor memory.

Discussion and Implications

Sex-specific multimorbid patterns identified in the Taiwanese older population showed differences (notably Renal-vascular pattern in men) from patterns found in Western countries and were differentially associated with cognitive impairment over time. When informative dropout is suspected, appropriate statistical methods should be applied.

Machine Learning-Based Classification of Subjective Cognitive Decline, Mild Cognitive Impairment, and Alzheimer's Dementia Using Neuroimage and Plasma Biomarkers

Alzheimer's disease (AD) progresses relentlessly from the preclinical to the dementia stage. The process begins decades before the diagnosis of dementia. Therefore, it is crucial to detect early manifestations to prevent cognitive decline. Recent advances in artificial intelligence help tackle the complex high-dimensional data encountered in clinical decision-making. In total, we recruited 206 subjects, including 69 cognitively unimpaired, 40 subjective cognitive decline (SCD), 34 mild cognitive impairment (MCI), and 63 AD dementia (ADD). We included 3 demographic, 1 clinical, 18 brain-image, and 3 plasma biomarker (Aß_1-42, Aß_1-40, and tau protein) features. We employed the linear discriminant analysis method for feature extraction to make data more distinguishable after dimension reduction. The sequential forward selection method was used for feature selection to identify the 12 best features for machine learning classifiers. We used both random forest and support vector machine as classifiers. The area under the receiver operative curve (AUROC) was close to 0.9 between diseased (combining ADD and MCI) and the controls. AUROC was higher than 0.85 between SCD and controls, 0.90 between MCI and SCD, and above 0.85 between ADD and MCI. We can differentiate between adjacent phases of the AD spectrum with blood biomarkers and brain MR images with the help of machine learning algorithms.

Distinct brain lipid signatures in response to low-level PM2.5 exposure in a 3xTg-Alzheimer's disease mouse inhalation model

Fine particulate matter (PM_2.5) poses a significant risk to human health. The molecular mechanisms underlying low-level PM_2.5-induced neurotoxicity in the central nervous system remain unclear. In addition, changes in lipids in response to PM_2.5 exposure have not yet been fully elucidated. In this study, 3xTg-Alzheimer's disease (AD) mice experienced continuous whole-body exposure to non-concentrated PM_2.5 for three consecutive months, while control mice inhaled particulate matter-filtered air over the same time span. A liquid chromatography-mass spectrometry-based lipidomic platform was used to determine the distinct lipid profiles of various brain regions. The average PM_2.5 concentration during the exposure was 11.38 μg/m³, which was close to the regulation limits of USA and Taiwan. The partial least squares discriminant analysis model showed distinct lipid profiles in the cortex, hippocampus, and olfactory bulb, but not the cerebellum, of mice in the exposure group. Increased levels of fatty acyls, glycerolipids, and sterol lipids, as well as the decreased levels of glycerophospholipids and sphingolipids in PM_2.5-exposed mouse brains may be responsible for the increased energy demand, membrane conformation, neuronal loss, antioxidation, myelin function, and cellular signaling pathways associated with AD development. Our research suggests that subchronic exposure to low levels of PM_2.5 may cause neurotoxicity by changing the lipid profiles in a susceptible model. Lipidomics is a powerful tool to study the early effects of PM_2.5-induced AD toxicity.

[Association of glutamate receptor metabotropic 5 polymorphisms with schizophrenia susceptibility in a Chinese Han population]

Objectives: To investigate the association of single nucleotide polymorphisms (SNP) of glutamate receptor metabotropic 5 (GRM5) gene with schizophrenia susceptibility(SZ) in a Chinese Han population. Methods: Twenty-two SNPs located in GRM5 gene in 528 paranoid SZ patients and 528 control subjects recruited from northern Henanwere analyzed. The clinical features of 267 first-episode SZ patients were assessed with the Positive and Negative Syndrome Scale (PANSS). Results: The SZ group included 264 males and 264 females, aged (27±8) years; the healthy control group had 264 males and 264 females, aged (28±8) years.The differences in the genotypic and allelic frequencies of two SNPs (rs567990 and rs12421343) were statistically significant between the SZ patients and control groups (all P<0.05). The allele frequency of rs504183 was also statistically different between the two groups (P=0.030). When the subjects were stratified by sex, the genotypic and allelic frequencies of rs12421343 in female subjects were statistically different between the SZ patients and control groups. The allele frequencies of SNPs (rs12422021, rs567990, and rs7101540) were also statisticallydifferent between the two groups (all P<0.05). Meanwhile, rs567990 AG+GG carriers had a higher risk for SZ than AA carriers in female subjects(OR=1.946, 95%CI: 1.264-2.995). In addition, the patients with different genotypes (GG, AA+AG) of rs12422021 showed statistically significant differences in PANSS total score(84.8±24.4 vs 75.3±18.6), positive (16.2±4.3 vs 14.4±4.2), excitement (12.4±5.1 vs 10.2±4.1) and cognitive impairment factor scores (15.2±6.8 vs 13.3±3.9) (all P<0.05). The patients with AC and the other two genotypes (AA and CC) of rs504183 showed statistically significant differences in PANSS negative factor score(27.4±9.9 vs 24.7±8.4 and 23.4±8.1, both P<0.05). Conclusion: The current study provides further evidence that GRM5 is associated with SZ, and suggests a putative sex difference.

White matter pathology in alzheimer's transgenic mice with chronic exposure to low-level ambient fine particulate matter

Background

Air pollution, especially fine particulate matter (PM), can cause brain damage, cognitive decline, and an increased risk of neurodegenerative disease, especially alzheimer’s disease (AD). Typical pathological findings of amyloid and tau protein accumulation have been detected in the brain after exposure in animal studies. However, these observations were based on high levels of PM exposure, which were far from the WHO guidelines and those present in our environment. In addition, white matter involvement by air pollution has been less reported. Thus, this experiment was designed to simulate the true human world and to discuss the possible white matter pathology caused by air pollution.

Results

6 month-old female 3xTg-AD mice were divided into exposure and control groups and housed in the Taipei Air Pollutant Exposure System (TAPES) for 5 months. The mice were subjected to the Morris water maze test after exposure and were then sacrificed with brain dissection for further analyses. The mean mass concentration of PM_2.5 during the exposure period was 13.85 μg/m³. After exposure, there was no difference in spatial learning function between the two groups, but there was significant decay of memory in the exposure group. Significantly decreased total brain volume and more neuronal death in the cerebral and entorhinal cortex and demyelination of the corpus callosum were noted by histopathological staining after exposure. However, there was no difference in the accumulation of amyloid or tau on immunohistochemistry staining. For the protein analysis, amyloid was detected at significantly higher levels in the cerebral cortex, with lower expression of myelin basic protein in the white matter. A diffuse tensor image study also revealed insults in multiple white matter tracts, including the optic tract.

Conclusions

In conclusion, this pilot study showed that even chronic exposure to low PM_2.5 concentrations still caused brain damage, such as gross brain atrophy, cortical neuron damage, and multiple white matter tract damage. Typical amyloid cascade pathology did not appear prominently in the vulnerable brain region after exposure. These findings imply that multiple pathogenic pathways induce brain injury by air pollution, and the optic nerve may be another direct invasion route in addition to olfactory nerve.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12989-022-00485-8.

Dysgraphia Phenotypes in Native Chinese Speakers With Primary Progressive Aphasia

BACKGROUND AND OBJECTIVES

Most primary progressive aphasia (PPA) literature is based on English language users. Linguistic features that vary from English, such as logographic writing systems, are underinvestigated. The current study characterized the dysgraphia phenotypes of patients with PPA who write in Chinese and investigated their diagnostic utility in classifying PPA variants.

METHODS

This study recruited 40 participants with PPA and 20 cognitively normal participants from San Francisco, Hong Kong, and Taiwan. We measured dictation accuracy using the Chinese Language Assessment for PPA (CLAP) 60-character orthographic dictation test and examined the occurrence of various writing errors across the study groups. We also performed voxel-based morphometry analysis to identify the gray matter regions correlated with dictation accuracy and prevalence of writing errors.

RESULTS

All PPA groups produced significantly less accurate writing responses than the control group and no significant differences in dictation accuracy were noted among the PPA variants. With a cut score of 36 out of 60 in the CLAP orthographic dictation task, the test achieved sensitivity and specificity of 90% and 95% in identifying Chinese participants with PPA vs controls. In addition to a character frequency effect, dictation accuracy was affected by homophone density and the number of strokes in semantic variant PPA and logopenic variant PPA groups. Dictation accuracy was correlated with volumetric changes over left ventral temporal cortices, regions known to be critical for orthographic long-term memory. Individuals with semantic variant PPA frequently presented with phonologically plausible errors at lexical level, patients with logopenic variant PPA showed higher preponderance towards visual and stroke errors, and patients with nonfluent/agrammatic variant PPA commonly exhibited compound word and radical errors. The prevalence of phonologically plausible, visual, and compound word errors was negatively correlated with cortical volume over the bilateral temporal regions, left temporo-occipital area, and bilateral orbitofrontal gyri, respectively.

DISCUSSION

The findings demonstrate the potential role of the orthographic dictation task as a screening tool and PPA classification indicator in Chinese language users. Each PPA variant had specific Chinese dysgraphia phenotypes that vary from those previously reported in English-speaking patients with PPA, highlighting the importance of language diversity in PPA.

A Digital Screening System for Alzheimer Disease Based on a Neuropsychological Test and a Convolutional Neural Network: System Development and Validation

Background

Alzheimer disease (AD) and other types of dementia are now considered one of the world’s most pressing health problems for aging people worldwide. It was the seventh-leading cause of death, globally, in 2019. With a growing number of patients with dementia and increasing costs for treatment and care, early detection of the disease at the stage of mild cognitive impairment (MCI) will prevent the rapid progression of dementia. In addition to reducing the physical and psychological stress of patients’ caregivers in the long term, it will also improve the everyday quality of life of patients.

Objective

The aim of this study was to design a digital screening system to discriminate between patients with MCI and AD and healthy controls (HCs), based on the Rey-Osterrieth Complex Figure (ROCF) neuropsychological test.

Methods

The study took place at National Taiwan University between 2018 and 2019. In order to develop the system, pretraining was performed using, and features were extracted from, an open sketch data set using a data-driven deep learning approach through a convolutional neural network. Later, the learned features were transferred to our collected data set to further train the classifier. The first data set was collected using pen and paper for the traditional method. The second data set used a tablet and smart pen for data collection. The system’s performance was then evaluated using the data sets.

Results

The performance of the designed system when using the data set that was collected using the traditional pen and paper method resulted in a mean area under the receiver operating characteristic curve (AUROC) of 0.913 (SD 0.004) when distinguishing between patients with MCI and HCs. On the other hand, when discriminating between patients with AD and HCs, the mean AUROC was 0.950 (SD 0.003) when using the data set that was collected using the digitalized method.

Conclusions

The automatic ROCF test scoring system that we designed showed satisfying results for differentiating between patients with AD and MCI and HCs. Comparatively, our proposed network architecture provided better performance than our previous work, which did not include data augmentation and dropout techniques. In addition, it also performed better than other existing network architectures, such as AlexNet and Sketch-a-Net, with transfer learning techniques. The proposed system can be incorporated with other tests to assist clinicians in the early diagnosis of AD and to reduce the physical and mental burden on patients’ family and friends.

Assessment of High Risk for Alzheimer's Disease Using Plasma Biomarkers in Subjects with Normal Cognition in Taiwan: A Preliminary Study

Background

In Alzheimer's disease (AD), cognitive impairment begins 10-15 years later than neurodegeneration in the brain. Plasma biomarkers are promising candidates for assessing neurodegeneration in people with normal cognition. It has been reported that subjects with the concentration of plasma amyloid-β 1-42×total tau protein higher than 455 pg²/ml² are assessed as having a high risk of amnesic mild impairment or AD, denoted as high risk of AD (HRAD).

Objective

The prevalence of high-risk for dementia in cognitively normal controls is explored by assaying plasma biomarkers.

Methods

422 subjects with normal cognition were enrolled around Taiwan. Plasma Aβ_1-40, Aβ_1-42, and T-Tau levels were assayed using immunomagnetic reduction to assess the risk of dementia.

Results

The results showed that 4.6% of young adults (age: 20-44 years), 8.5% of middle-aged adults (age: 45-64 years), and 7.3% of elderly adults (age: 65-90 years) had HRAD. The percentage of individuals with HRAD dramatically increased in middle-aged and elderly adults compared to young adults.

Conclusion

The percentage of HRAD in cognitively normal subjects are approximately 10%, which reveals that the potentially public-health problem of AD in normal population. Although the subject having abnormal levels of Aβ or tau is not definitely going on to develop cognitive declines or AD, the risk of suffering cognitive impairment in future is relatively high. Suitable managements are suggested for these high-risk cognitively normal population. Worth noting, attention should be paid to preventing cognitive impairment due to AD, not only in elderly adults but also middle-aged adults.

The association between metabolic syndrome and successful aging- using an extended definition of successful aging

Objectives

To examine the association between metabolic syndrome (MetS) and successful aging among community-dwelling older adults.

Methods

Adults aged ≥ 65 years who participated in the senior health checkup program at National Taiwan University Hospital during 2011–2013 were recruited (N = 467 at baseline). The participants were followed after 4 years and 6 years. MetS was assessed at baseline. Successful aging was evaluated at baseline, 4-year follow-up, and 6-year follow-up. We adopted an extended definition of successful aging, which was defined as three major domains: physiological, psychological, and sociological and economic domains. Generalized linear mixed models were used to assess the association between MetS and successful aging adjusting for time (follow-up years), age, sex, years of education, alcohol consumption and MetS×time interaction term.

Results

The mean age of the study population was 72.9 (SD 5.5) years. The absence of baseline MetS had a positive effect on the probability of successful aging over six years. The absences of abdominal obesity, hyperglycemia, reduced high-density lipoprotein cholesterol, and hypertension were associated with the physiological successful aging. The absence of hypertension was the most significant predictor of physiological successful aging [aOR (95% CI) = 2.76 (1.67–4.58), p<0.001]. Significant increased trend was found in the overall and physiological successful aging across MetS status (No MetS, pre MetS, MetS; P_trend <0.001).

Conclusions

We found that MetS is a risk factor of successful aging among community-dwelling older adults. Public health policy should aim at avoidance of MetS in order to facilitate successful aging in older population.

A Longitudinal Study on the Association of Interrelated Factors Among Frailty Dimensions, Cognitive Domains, Cognitive Frailty, and All-Cause Mortality

BACKGROUND

Cognitive frailty integrating impaired cognitive domains and frailty dimensions has not been explored.

OBJECTIVE

This study aimed to explore 1) associations among frailty dimensions and cognitive domains over time and 2) the extended definitions of cognitive frailty for predicting all-cause mortality.

METHODS

This four-year cohort study recruited 521 older adults at baseline (2011-2013). We utilized 1) generalized linear mixed models exploring associations of frailty dimensions (physical dimension: modified from Fried et al.; psychosocial dimension: integrating self-rated health, mood, and social relationship and support; global frailty: combining physical and psychosocial frailty) with cognition (global and domain-specific) over time and 2) time-dependent Cox proportional hazard models assessing associations between extended definitions of cognitive frailty (cognitive domains-frailty dimensions) and all-cause mortality.

RESULTS

At baseline, the prevalence was 3.0%for physical frailty and 37.6%for psychosocial frailty. Greater physical frailty was associated with poor global cognition (adjusted odds ratio = 1.43-3.29, β: -1.07), logical memory (β: -0.14 to -0.10), and executive function (β: -0.51 to -0.12). Greater psychosocial frailty was associated with poor global cognition (β: -0.44) and attention (β: -0.15 to -0.13). Three newly proposed definitions of cognitive frailty, "mild cognitive impairment (MCI)-psychosocial frailty," "MCI-global frailty," and "impaired verbal fluency-global frailty," outperformed traditional cognitive frailty for predicting all-cause mortality (adjusted hazard ratio = 3.49, 6.83, 3.29 versus 4.87; AIC = 224.3, 221.8, 226.1 versus 228.1).

CONCLUSION

Notably, extended definitions of cognitive frailty proposed by this study better predict all-cause mortality in older adults than the traditional definition of cognitive frailty, highlighting the importance of psychosocial frailty to reduce mortality in older adults.

Effectiveness of the 10 cm2 Rivastigmine Patch in Taiwanese Patients with Mild-to-Moderate Alzheimer's Dementia: A 48-Week Real-World Observational Study

Introduction

The current study aimed to provide data on the effectiveness of the 10 cm² rivastigmine patch in patients with Alzheimer’s disease (AD) in a real-world setting in Taiwan.

Methods

This was a 48-week, single-arm, open-label, observational, and post-marketing study conducted across seven centers in Taiwan between May 5, 2016 and July 10, 2017. Eligible patients (aged 55–95 years) treated with the 10 cm²rivastigmine patch were enrolled based on physicians’ judgment and according to the Taiwan reimbursement criteria of the drug. Data were prospectively collected at Week 0 (baseline), Week 24, and Week 48. The primary endpoint was the change in the cognitive assessment screening instrument (CASI) scores at Week 48 versus baseline. The changes from baseline in clinical dementia rating (CDR), mini-mental state examination (MMSE), and neuropsychiatric inventory (NPI) scores were evaluated, as were treatment persistence and the safety profile.

Results

Of the 285 eligible patients [full analysis set (FAS)], 216 (75.8%) completed the study protocol while 180 (63.2%) persisted on the 10 cm² rivastigmine patch for the full 48 weeks. At baseline, 89.8% of patients had a CDR score of 0.5 or 1, while the change in CDR score at Week 48 was not significant. In the FAS, both the CASI and MMSE scores had numerical improvement at Week 24 but declined by 2.1 and 0.4 points, respectively, at Week 48 (p = 0.005 and p = 0.022). The increment in NPI scores was not significant. The most common drug-related adverse events (AEs) were pruritus (11.2%), nausea (3.5%), rash (3.2%), and vomiting (2.8%).

Conclusions

The use of the 10 cm² rivastigmine patch in the mild stage of AD maintained cognitive function at Week 24 and neuropsychiatric function at Week 48. The treatment persistency and safety profile support the clinical tolerability of the rivastigmine patch in the management of mild-to-moderate AD in Taiwan.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-021-01893-6.

Investigation of the Number of Tests Required for Assaying Plasma Biomarkers Associated with Alzheimer's Disease Using Immunomagnetic Reduction

INTRODUCTION

Concentrations of plasma biomarkers associated with Alzheimer's disease have been reported to be as low as several tens of picograms/milliliter (pg/ml). However, in assays measuring these biomarkers, it is likely that repeated measurements are necessary to obtain reliable values.

METHODS

We performed assays as a single test or as duplicate, quadruplicate, fivefold and tenfold repeated tests, on samples spiked with different concentrations of amyloid β 1-40 (Aβ_1-40; 1-1000 pg/ml), Aβ_1-42 (1-30,000 pg/ml) and total Tau protein (T-Tau; 0.1-1000 pg/ml), with the aim to to calculate the coefficients of variation (CVs).

RESULTS

The results demonstrated common changes in the CVs with changes in the number of tests for a given sample: the CVs decreased with increases in the number of tests from one to ten. All CV values were distributed within the range of 0.35 to 15.5%; as such, the CV values were all lower than the acceptable value of 20%.

CONCLUSION

Based on this study, a single assay of Aβ_1-40, Aβ_1-42 and T-Tau, respectively, provides reliable results in terms of the measurement of that plasma biomarker.

An Exploration of the Own-Age Effect on Facial Emotion Recognition in Normal Elderly People and Individuals with the Preclinical and Demented Alzheimer's Disease

BACKGROUND

The issue of whether there exists an own-effect on facial recognition in the elderly remains equivocal. Moreover, currently the literature of this issue in pathological aging is little.

OBJECTIVE

Our study was thus to explore the issue in both of healthy older people and patients with ADMethods:In study 1, 27 older and 31 younger healthy adults were recruited; in study 2, 27 healthy older adults and 80 patients (including subjective cognitive decline (SCD), mild cognitive impairment (MCI), and Alzheimer's disease (AD) groups) were recruited. Participants received the Taiwan Facial Emotion Recognition Task (FER Task), and a clinical neuropsychological assessment.

RESULTS

No significant differences on the FER test were found among our groups, except for sadness recognition in which our MCI and AD patients' scores were remarkably lower than their healthy counterparts. The own-age effect was not significantly evident in healthy younger and older adults, except for recognizing neutral photos. Our patients with MCI and AD tended to have the effect, particularly for the sad recognition in which the effect was significantly evident in terms of error features (mislabeling it as anger in younger-face and neutral in older-face photos).

CONCLUSION

Our results displayed no remarkable own-age effect on facial emotional recognition in the healthy elderly (including SCD). However, it did not appear the case for MCI and AD patients, especially their recognizing those sadness items, suggesting that an inclusion of the FER task particularly involving those items of low-intensity emotion in clinical neuropsychological assessment might be contributory to the early detection of AD-related pathological individuals.

Prognostic Features of Sporadic Creutzfeldt-Jakob Disease: An Analysis of Taiwan's Nationwide Surveillance

OBJECTIVES

To study the prognostic features of Creutzfeldt-Jakob disease (CJD) and shed light on its future therapy.

DESIGN

Retrospective cohort study of a longitudinal national cohort of the Taiwan Centers for Disease Control.

SETTING AND PARTICIPANTS

All patients with suspected CJD are reported to the CJD surveillance unit of the Taiwan Centers for Disease Control. An expert committee discussed the reported cases and designated a consensus-based diagnosis. From 1996 to 2020, a total of 809 cases were referred to the CJD surveillance unit for confirmation; of these, 441 cases (women, n = 230) were determined to be sporadic CJD.

METHODS

We investigated the clinical manifestations and laboratory findings for 400 patients diagnosed with definite or probable sporadic CJD. We used Kaplan-Meier analyses and Cox proportional hazards model to identify prognostic factors.

RESULTS

The mean age of onset was 67 ± 9.9 years. The mean survival duration was 13.3 ± 14.2 (median 10) months. The leading clinical symptoms were myoclonus (73%) and akinetic mutism (54%). For PRNP polymorphism, 99% of patients (195/197) showed a methionine homozygous genotype at codon 129 (M129M). The sensitivity of periodic sharp wave complexes (PSWCs) on electroencephalograms (EEGs) was 59.7%. The sensitivity of cerebrospinal fluid 14-3-3 protein and total tau protein (>1200 pg/mL) were 69.7% and 75.6%, respectively. Younger patients lived longer than those aged ≥65 years [hazard ratio (HR) 0.466, P < .001]. Women had a better survival probability in the first 3 years than their male counterparts (HR 0.712, P = .005). PSWCs had a persistent negative effect on survival (HR 0.788, P < .05). Although uncommon, epileptic seizures were the only clinical prognostic factor for survival time (HR 0.768, P < .05). PSWCs can be used as an EEG biomarker for prognosis. Epileptic seizures, though not common, are the only clinical prognostic factor for a short survival.

CONCLUSIONS AND IMPLICATIONS

We found that a lower age of onset and female gender favor the survival of patients with sCJD. PSWCs are EEG biomarkers unfavorable for survival, and so are epileptic seizures.

Impacts of Kidney Dysfunction and Cerebral Cortical Thinning on Cognitive Change in Elderly Population

BACKGROUND

Cerebral cortical thickness is a neuroimaging biomarker to predict cognitive decline, and kidney dysfunction (KD) is associated with cortical thinning.

OBJECTIVE

This study aimed to investigate the effects of KD and cortical thinning on cognitive change in a prospective cohort study.

METHODS

A total of 244 non-demented participants were recruited from elderly health checkup program and received cognitive exams including Montreal Cognitive Assessment (MoCA) and different cognitive domains at baseline and three biannual follow-ups afterwards. KD was defined as having either glomerular filtration rate <60 ml/min/1.73 m2 or proteinuria. Cortical thickness of global, lobar, and Alzheimer's disease (AD) signature area were derived from magnetic resonance imaging at baseline, and cortical thinning was defined as the lowest tertile of cortical thickness. Generalized linear mixed models were applied to evaluate the effects of KD and cortical thinning on cognitive changes.

RESULTS

KD was significantly associated with the decline in attention function (β= -0.29). Thinning of global (β= -0.06), AD signature area (β= -0.06), temporal (β= -0.06), and parietal lobes (β= -0.06) predicted poor verbal fluency over time, while temporal lobe thinning also predicted poor MoCA score (β= -0.19). KD modified the relationship between thinning of global, frontal, and limbic, and change of logical memory function (pinteraction < 0.05). When considering jointly, participants with both KD and cortical thinning had greatest decline in attention function compared with those without KD or cortical thinning (β= -0.51, ptrend = 0.008).

CONCLUSIONS

KD and cortical thinning have joint effect on cognitive decline, especially the attention function. Reverse associations may exist between cortical thinning and memory function in participants with KD, though the results should be interpreted cautiously as an exploratory analysis.

Synergistic Association between Plasma Aβ1-42 and p-tau in Alzheimer's Disease but Not in Parkinson's Disease or Frontotemporal Dementia

Beta-amyloid (Aβ_1–42) triggers the phosphorylation of tau protein in Alzheimer’s disease (AD), but the relationship between phosphorylated tau (p-tau) and Aβ_1–42 in the blood is not elucidated. We investigated the association in individuals with AD (n = 62, including amnesic mild cognitive impairment and dementia), Parkinson’s disease (n = 30), frontotemporal dementia (n = 25), and cognitively unimpaired controls (n = 41) using immunomagnetic reduction assays to measure plasma Aβ_1–42 and p-tau181 concentrations. Correlation and regression analyses were performed to examine the relation between plasma levels, demographic factors, and clinical severity. Both plasma Aβ_1–42 and p-tau concentrations were significantly higher in AD and frontotemporal dementia than in the controls and Parkinson’s disease. A significant positive association was found between plasma p-tau and Aβ_1–42 in controls (r = 0.579, P < 0.001) and AD (r = 0.699, P < 0.001) but not in frontotemporal dementia or Parkinson’s disease. Plasma p-tau was significantly associated with clinical severity in the AD in terms of scores of clinical dementia rating (r = 0.288, P = 0.025) and mini-mental state examination (r = −0.253, P = 0.049). Regression analysis showed that plasma Aβ_1–42 levels explain approximately 47.7% of the plasma p-tau levels in the AD after controlling age, gender, and clinical severity. While in non-AD participants, the clinical dementia rating explained about 47.5% of the plasma p-tau levels. The disease-specific association between plasma Aβ_1–42 and p-tau levels in AD implies a possible synergic effect in mechanisms involving these two pathological proteins’ genesis.

Integrated 18F-T807 Tau PET, Structural MRI, and Plasma Tau in Tauopathy Neurodegenerative Disorders

Background and Objective: Tau-specific positron emission topography (PET) imaging enables in vivo assessment of Alzheimer's disease (AD). We aimed to investigate its performance in combination with plasma tau levels in patients with non-AD tauopathy.

Methods: A total of 47 participants were enrolled, including 10 healthy controls, 16 with tauopathy parkinsonism syndromes (9 with corticobasal syndrome [CBS], 7 with progressive supranuclear palsy [PSP]), 9 with frontotemporal dementia (FTD), 4 with AD, and 8 with Parkinson's disease (PD). All participants underwent clinical assessments, ¹⁸F-T807 tau PET, brain MRI, and plasma tau assay.

Results: The global cortical standard uptake value ratio (SUVR) of ¹⁸F-T807 PET was comparable between PD and control (p = 0.088). The cortical SUVR was significantly higher in AD group (p = 0.002) but was modestly increased in PSP group compared to the PD group (p = 0.044), especially in parietal and pallidal regions. Asymmetric ¹⁸F-T807 uptake at the pallidum was noted in patients with CBS and FTD. Cortical tau tracer uptake was associated with increased plasma total tau level (p = 0.016), especially in frontal and parietal regions. Regional tracer uptake was correlated with cortical thinning in patients with CBS and PSP (CBS: r = −0.092, p = 0.025; PSP: r = −0.114, p = 0.015).

Conclusions: The ¹⁸F-T807 tau tracer uptake was only modestly increased in patients with PSP. Although the cortical tau tracer uptake correlated with regional cortical atrophy and plasma tau levels, a four-repeated tau-specific tracer is needed for future classifying tauopathy parkinsonism syndromes.

Genetic study of young-onset dementia using targeted gene panel sequencing in Taiwan

Recent genetic progress allows the molecular diagnosis of young-onset dementia, including Alzheimer's disease (AD) and frontotemporal dementia (FTD). We aimed to identify the mutational and clinical spectra of causal genes in a Taiwanese cohort of young-onset dementia. Ninety-one patients with young-onset dementia and 22 age/gender-matched controls were recruited. Genetic causes were identified by a targeted panel containing 90 causative genes for AD, FTD, and related neurodegenerative disorders. Plasma biomarkers, including total tau, Aβ42, and Aβ40, were assayed. Molecular amyloid and tau PET scans were performed in some patients carrying mutations. Nine of 52 patients (17.3%) with young-onset AD had mutations: 2 (22.2%), 4 (44.5%), 2 (22.2%), and 1 (11.1%) in APP, PSEN1, PSEN2, and TREM2, respectively. Two of 33 patients (6.1%) with young-onset FTD had mutations in MAPT and LRRK2. Three of the 6 patients (50.0%) with possible FTD combined with other neurodegenerative disorders had individual mutations in APP, PSEN2, or MAPT. Patients with PSEN1 mutations had earlier onset of disease than those without mutations (p = .02). Plasma level of total tau was increased and Aβ42 and Aβ40 levels decreased in all groups of dementia patients compared to controls. Our findings provide a genetic spectrum of young-onset dementia in our population.

Neuropathology changed by 3- and 6-months low-level PM2.5 inhalation exposure in spontaneously hypertensive rats

Background

Epidemiological evidence has linked fine particulate matter (PM_2.5) to neurodegenerative diseases; however, the toxicological evidence remains unclear. The objective of this study was to investigate the effects of PM_2.5 on neuropathophysiology in a hypertensive animal model. We examined behavioral alterations (Morris water maze), lipid peroxidation (malondialdehyde (MDA)), tau and autophagy expressions, neuron death, and caspase-3 levels after 3 and 6 months of whole-body exposure to urban PM_2.5 in spontaneously hypertensive (SH) rats.

Results

SH rats were exposed to S-, K-, Si-, and Fe-dominated PM_2.5 at 8.6 ± 2.5 and 10.8 ± 3.8 μg/m³ for 3 and 6 months, respectively. We observed no significant alterations in the escape latency, distance moved, mean area crossing, mean time spent, or mean swimming velocity after PM_2.5 exposure. Notably, levels of MDA had significantly increased in the olfactory bulb, hippocampus, and cortex after 6 months of PM_2.5 exposure (p < 0.05). We observed that 3 months of exposure to PM_2.5 caused significantly higher expressions of t-tau and p-tau in the olfactory bulb (p < 0.05) but not in other brain regions. Beclin 1 was overexpressed in the hippocampus with 3 months of PM_2.5 exposure, but significantly decreased in the cortex with 6 months exposure to PM_2.5. Neuron numbers had decreased with caspase-3 activation in the cerebellum, hippocampus, and cortex after 6 months of PM_2.5 exposure.

Conclusions

Chronic exposure to low-level PM_2.5 could accelerate the development of neurodegenerative pathologies in subjects with hypertension.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12989-020-00388-6.

Long-Term Exposure to Air Pollutants and Cognitive Function in Taiwanese Community-Dwelling Older Adults: A Four-Year Cohort Study

BACKGROUND

Previous studies have assessed limited cognitive domains with relatively short exposure to air pollutants, and studies in Asia are limited.

OBJECTIVE

This study aims to explore the association between long-term exposure to air pollutants and cognition in community-dwelling older adults.

METHODS

This four-year prospective cohort study recruited 605 older adults at baseline (2011-2013) and 360 participants remained at four-year follow-up. Global and domain-specific cognition were assessed biennially. Data on PM2.5 (particulate matter≤2.5μm diameter, 2005-2015), PM10 (1993-2015), and nitrogen dioxide (NO2, 1993-2015) were obtained from Taiwan Environmental Protection Administration (TEPA). Bayesian Maximum Entropy was utilized to estimate the spatiotemporal distribution of levels of these pollutants.

RESULTS

Exposure to high-level PM2.5 (>29.98μg/m3) was associated with an increased risk of global cognitive impairment (adjusted odds ratio = 4.56; β= -0.60). High-level PMcoarse exposure (>26.50μg/m3) was associated with poor verbal fluency (β= -0.19). High-level PM10 exposure (>51.20μg/m3) was associated with poor executive function (β= -0.24). Medium-level NO2 exposure (>28.62 ppb) was associated with better verbal fluency (β= 0.12). Co-exposure to high concentrations of PM2.5, PMcoarse or PM10 and high concentration of NO2 were associated with poor verbal fluency (PM2.5 and NO2: β= -0.17; PMcoarse and NO2: β= -0.23; PM10 and NO2: β= -0.21) and poor executive function (PM10 and NO2: β= -0.16). These associations became more evident in women, apolipoprotein ɛ4 non-carriers, and those with education > 12 years.

CONCLUSION

Long-term exposure to PM2.5 (higher than TEPA guidelines), PM10 (lower than TEPA guidelines) or co-exposure to PMx and NO2 were associated with poor global, verbal fluency, and executive function over 4 years.

Incidence of and Mortality Due to Human Prion Diseases in Taiwan: A Prospective 20-Year Nationwide Surveillance Study from 1998 to 2017

Introduction

Epidemiologic studies of Creutzfeldt-Jakob disease (CJD) have been undertaken worldwide since the new variant CJD outbreak in 1996 in the United Kingdom. A nationwide report system, the Creutzfeldt-Jakob Disease Surveillance Unit (CJDSU), directed by the Centers for Disease Control of Taiwan, was established in 1997 to identify human prion diseases.

Methods

From 1998 to 2017, 647 cases were referred to the committee for confirmation. The report to CJDSU included a structured questionnaire recording the clinical, demographic data, and potential iatrogenic exposure, and the results of the clinical and laboratory examination, including tests of blood and cerebrospinal fluid, electroencephalography, and brain magnetic resonance imaging.

Results

In total, 356 cases (women, n=178) were ascertained to be human prion diseases, and 97.4% (n=347) were sporadic CJD, including three definite, 314 probable, and 30 possible cases; one probable variant CJD and 8 cases of the genetic form human prion diseases. The age- and gender-specific average annual incidence were also significantly higher in the second decade (0.95/1,000,000) than in the first decade (0.63/1,000,000), with an incidence rate ratio of 1.51. The incidences increased with increasing age, reaching a peak at the age of 70-79 years. The 10-year survival curve for sCJD patients showed that the 1-, 5-, and 10-year cumulative survival rate were 52%, 5%, and 1%, respectively. PRNP polymorphisms in 170 patients showed that 98.8% were M129M and 97.6% E219E.

Discussion

The significant increase in incidence after 2008 suggests the increase in the awareness of this rare disease among physicians. The longer disease duration in patients with sCJD in Taiwan than in other countries indicates that the comprehensive support of the health care system, as well as the end-of-life care culture in Taiwan, may prolong survival time in patients with such a progressive and fatal disease.

Classifications of Neurodegenerative Disorders Using a Multiplex Blood Biomarkers-Based Machine Learning Model

Easily accessible biomarkers for Alzheimer's disease (AD), Parkinson's disease (PD), frontotemporal dementia (FTD), and related neurodegenerative disorders are urgently needed in an aging society to assist early-stage diagnoses. In this study, we aimed to develop machine learning algorithms using the multiplex blood-based biomarkers to identify patients with different neurodegenerative diseases. Plasma samples (n = 377) were obtained from healthy controls, patients with AD spectrum (including mild cognitive impairment (MCI)), PD spectrum with variable cognitive severity (including PD with dementia (PDD)), and FTD. We measured plasma levels of amyloid-beta 42 (Aβ42), Aβ40, total Tau, p-Tau181, and α-synuclein using an immunomagnetic reduction-based immunoassay. We observed increased levels of all biomarkers except Aβ40 in the AD group when compared to the MCI and controls. The plasma α-synuclein levels increased in PDD when compared to PD with normal cognition. We applied machine learning-based frameworks, including a linear discriminant analysis (LDA), for feature extraction and several classifiers, using features from these blood-based biomarkers to classify these neurodegenerative disorders. We found that the random forest (RF) was the best classifier to separate different dementia syndromes. Using RF, the established LDA model had an average accuracy of 76% when classifying AD, PD spectrum, and FTD. Moreover, we found 83% and 63% accuracies when differentiating the individual disease severity of subgroups in the AD and PD spectrum, respectively. The developed LDA model with the RF classifier can assist clinicians in distinguishing variable neurodegenerative disorders.

The contribution of vascular risk factors in neurodegenerative disorders: from mild cognitive impairment to Alzheimer's disease

Background

Optimization of vascular risk factor control is emerging as an alternative approach to improve cognitive outcomes in Alzheimer’s disease, although its efficacy is still under debate. We aimed to investigate the contribution of vascular risk factors on Alzheimer’s biomarkers and conversion rate to dementia in subjects with mild cognitive impairment (MCI) with low cerebral small vessel disease burden.

Methods

Two hundred ninety-five newly diagnosed MCI subjects were enrolled from March 2005 to May 2017 for a cross-sectional assessment of vascular risk factors and Alzheimer’s plasma and imaging biomarkers, followed by a cognitive outcome assessment 24 months after enrollment. The association between vascular risk factors and Alzheimer’s biomarkers were tested using multivariable linear regression models adjusted with age, gender, education, and APOE ε4 allele. The association between vascular risk factors and conversion to dementia was tested using multivariable logistic regression models adjusted with age, gender, education, and baseline Mini-Mental State Examination (MMSE) score.

Results

At baseline, higher low-density lipoprotein (LDL) cholesterol level was associated with more advanced plasma biomarkers, including Aβ42/Aβ40 ratio (P = 0.012) and tau level (P = 0.001). A history of hypertension was associated with more advanced white matter hyperintensity (P = 0.011), while statin therapy for dyslipidemia was associated with less advanced white matter hyperintensity (P = 0.002). At 24 months, individual vascular risk factor was not significantly associated with cognitive outcome. By contrast, statin therapy for dyslipidemia was associated with reduced conversion to dementia (adjusted OR = 0.191, 95% CI = 0.062~0.586, P = 0.004).

Conclusions

For MCI subjects, dyslipidemia may contribute to AD-related neurodegeneration while hypertension may contribute to vascular pathology. The association between statin therapy for dyslipidemia and reduced conversion to dementia supports further interventional study to evaluate the potential beneficial effect of statin in MCI subjects.

Nanoparticle-based immunomagnetic assay of plasma biomarkers for differentiating dementia and prodromal states of Alzheimer's disease - A cross-validation study

Blood-based biomarker assays of plasma β-amyloid (Aβ) and tau have the advantages of cost-effective and less invasive for the diagnosis of Alzheimer's disease (AD). We used two independent cohorts to cross-validate the clinical use of the nanoparticle-based immunomagnetic assay of plasma biomarkers to assist in the differential diagnosis of early AD. There were in total 160 subjects in the derivation cohort, and 242 in the validation cohort both containing controls, mild cognitive impairment due to AD and AD dementia diagnosed according to the 2011 NIA-AA guidelines. The cutoff value for plasma Aβ_1-42 (16.4 pg/ml) performed the best in differentiating between controls and patients with prodromal or clinical AD, with 92.5% for positive percent agreement (PPA), negative percent agreement (NPA), and overall rate of agreement (ORA). Aβ_1-42 × tau (642.58) was useful for separating patients with dementia and prodromal states of AD, with 84.9% PPA, 78.8% NPA and 83% ORA.

Brain lipid profiles in the spontaneously hypertensive rat after subchronic real-world exposure to ambient fine particulate matter

Recent studies have illustrated an association between ambient fine particulate matter (PM_2.5) exposure and neuronal toxicity in epidemiological studies and animal models. However, the possible molecular effects on brains under real-world exposure to PM_2.5 remain unclear. In this pilot study, male spontaneously hypertensive rats were whole-bodily exposed to ambient air from the outdoor environment of Taipei City for 3 months, while the control rats inhaled HEPA-filtered air. The PM_2.5-induced phosphatidylcholine and sphingomyelin profiles in the hippocampus, cortex, medulla, cerebellum, and olfactory bulb were assessed by mass spectrometry (MS)-based lipidomics. Partial least squares discriminant analysis (PLS-DA) and the Wilcoxon rank sum test were used to examine the lipid changes between the exposed and control groups. The PLS-DA models showed that phosphatidylcholine and sphingomyelin profiles of the PM_2.5 exposure group were different from those of the control group in each brain region except the cortex. More lipid changes were found in the hippocampus, while fewer lipid changes were observed in the olfactory bulb. The lipid alteration in the hippocampus may strengthen membrane integrity, modulate signaling pathways, and avoid accumulation of lipofuscin to counter the PM_2.5-induced stress. The lipid changes in the cortex and medulla may respond to PM_2.5-induced injury and inflammation; while the lipid changes in the cerebellum were associated with neuron protection. This study suggests that the MS-based lipidomics is a powerful approach to discriminate the brain lipid profiles even at the environmental level of ambient PM_2.5 and has the potential to suggest possible adverse health effects in long-term PM_2.5 exposure studies.

Frontal variant of Alzheimer's disease with asymmetric presentation mimicking frontotemporal dementia: Case report and literature review

INTRODUCTION

Frontal variant of Alzheimer's disease (fvAD) is a rare nonamnestic syndrome of Alzheimer's disease (AD). Differentiating it from behavior variant of frontotemporal dementia (bvFTD), which has implications for treatment responses and prognosis, remains a clinical challenge.

METHODS

Molecular neuroimaging and biofluid markers were performed for the index patient for accurate premortem diagnosis of fvAD. The clinical, neuroimaging, and biofluid characteristics of the patient were compared to those reported in previous studies of fvAD from 1999 to 2019.

RESULTS

A 66-year-old man presented with progressive executive dysfunction, personality and behavioral changes, and memory decline since age 59. He had no family history of neurodegenerative disorders. A stimulus-sensitive myoclonus was noted over his left upper extremity. Neuropsychological assessment revealed moderate dementia with a Mini-Mental State Exam score of 10/30 and compromised executive and memory performance. Brain imaging showed asymmetrical atrophy and hypometabolism over the right frontal and temporal areas, mimicking bvFTD. However, we observed increased tau depositions based on ¹⁸ F-labeled T807 Tau PET in these areas and diffusely increased amyloid deposition based on ¹¹ C-labeled Pittsburgh compound B positron emission tomography (PET). Plasma biomarker measures indicated an AD profile with increased Aβ1-42 (18.66 pg/ml; cutoff: 16.42 pg/ml), Aβ1-42/Aβ1-40 ratio (0.45; cutoff: 0.30), total tau (29.78 pg/ml; cutoff: 23.89 pg/ml), and phosphorylated tau (4.11 pg/ml; cutoff: 3.08 pg/ml). These results supported a diagnosis of fvAD.

CONCLUSIONS

Our results with asymmetrical presentations extend current knowledge about this rare AD variant. Application of biofluid and molecular imaging markers could assist in early, accurate diagnosis.

Age-Dependent Relationship Between Plasma Aβ40 and Aβ42 and Total Tau Levels in Cognitively Normal Subjects

Both amyloid plaques and neurofibrillary tangles are pathological hallmarks in the brains of patients with Alzheimer’s disease (AD). However, the constituents of these hallmarks, amyloid beta (Aβ) 40, Aβ42, and total Tau (t-Tau), have been detected in the blood of cognitively normal subjects by using an immunomagnetic reduction (IMR) assay. Whether these levels are age-dependent is not known, and their interrelation remains undefined. We determined the levels of these biomarkers in cognitively normal subjects of different age groups. A total of 391 cognitively normal subjects aged 23–91 were enrolled from hospitals in Asia, Europe, and North America. Healthy cognition was evaluated by NIA-AA guidelines to exclude subjects with mild cognitive impairment (MCI) and AD and by cognitive assessment using the Mini Mental State Examination and Clinical Dementia Rating (CDR). We examined the effect of age on plasma levels of Aβ40, Aβ42, and t-Tau and the relationship between these biomarkers during aging. Additionally, we explored age-related reference intervals for each biomarker. Plasma t-Tau and Aβ42 levels had modest but significant correlations with chronological age (r = 0.127, p = 0.0120 for t-Tau; r = −0.126, p = 0.0128 for Aβ42), ranging from ages 23 to 91. Significant positive correlations were detected between Aβ42 and t-Tau in the groups aged 50 years and older, with Rho values ranging from 0.249 to 0.474. Significant negative correlations were detected between Aβ40 and t-Tau from age 40 to 91 (r ranged from −0.293 to −0.582) and between Aβ40 and Aβ42 in the age groups of 30–39 (r = −0.562, p = 0.0235), 50–59 (r = −0.261, p = 0.0142), 60–69 (r = −0.303, p = 0.0004), and 80–91 (r = 0.459, p = 0.0083). We also provided age-related reference intervals for each biomarker. In this multicenter study, age had weak but significant effects on the levels of Aβ42 and t-Tau in plasma. However, the age group defined by decade revealed the emergence of a relationship between Aβ40, Aβ42, and t-Tau in the 6th and 7th decades. Validation of our findings in a large-scale and longitudinal study is warranted.

Genetic Structure Analysis of Y-Chromosome STR and SNP in Population of Wujiang Area, Suzhou City

Abstract

Objective To analyze the genetic phenotypes of Y-chromosome STR and SNP in Han male population of Wujiang area, Suzhou City and explore the genetic structure of population of Wujiang area for further examination of regional-specific Y-SNP genetic markers ancestor haplogroups. Methods Blood samples of 472 Wujiang area Han males were randomly collected and genotyped by Yfiler^TM Plus PCR Amplification Kit. The allele frequencies and haplotype frequencies of each locus were obtained using the direct calculation method. Y-SNP haplogroups of each sample were estimated using Y-Predictor software and verified through experiments by amplification refractory mutation system-polymerase chain reaction （ARMS-PCR）. Results A total of 453 haplotypes were found in the 27 Y-STR genetic markers in 472 Han males of Wujiang area. The haplotype diversity （HD） was 0.997 696 93, among which, the highest gene diversity （GD） value was DYF387S1a/b （GD=0.953 1） and the lowest was DYS438 （GD=0.321 8）. Based on genotyping data of 27 Y-STRs and 472 samples, 132 haplogroups from C, D, N, O and Q, etc downstream Y-SNP haplogroups were estimated and then verified through experiments. Conclusion This study is based on Y-chromosome STR haplotypes, and predicts Y-SNP haplogroups by Y-Predictor software, then uses ARMS-PCR to verify. Y-SNP genetic markers were introduced to achieve precise analysis of the genetic structure of male families in population of three towns in Wujiang area.

The Social Functioning Scale for Alzheimer's Disease: A Short Informant-based Measure of Functional Status in Patients with Alzheimer's Disease in Taiwan

OBJECTIVE

Evaluating social-functioning impairments in patients with Alzheimer's disease (AD) objectively is essential for clinical service. However, the existing instruments lack representative content, consensus on purposes of use, and adequate scoring systems and samples. This study was thus to develop a social functioning scale for patients: the Social Functioning Scale for Alzheimer's Disease (SFSAD).

METHOD

Questionnaires were analyzed from 142 AD patients, 30 patients with amnestic mild cognitive impairment (aMCI), and 50 normal controls.

RESULTS

Based on the literature review and experts' opinions, the final scale includes 20 items in four subscales. The SFSAD showed high internal consistency coefficients (Cronbach's α = .97) and test-retest reliability (r = .99) coefficients. The content validity was desirable, and the criterion-related validity was demonstrated by a significant association with the MMSE, the IADL, and the Barthel ADL. The discriminant validity of the scale was also demonstrated as the level of social-functioning impairment was significantly related to the degree of dementia, and for construct validity, our findings supported the structure of the four-factor hypothesized model.

CONCLUSIONS

The SFSAD is thus a practical, psychometrically sound, and easy-to-administer measure to evaluate social functioning of AD and aMCI in brisk clinical settings.

Persistence and adherence to rivastigmine in patients with dementia: Results from a noninterventional, retrospective study using the National Health Insurance research database of Taiwan

Introduction

The objective of the study was to assess adherence and persistence of patients treated with rivastigmine versus donepezil.

Methods

Persistence was calculated as the time from the first prescription date of rivastigmine/donepezil until discontinuation/medication switch/end of available data, whichever occurred first. Adherence was calculated as proportion of days covered and medication possession ratio.

Results

A majority of patients persisted on 4.5 and 6 mg of rivastigmine for 429 and 468 days, respectively, versus 443 and 441 days for patients receiving 5 and 10 mg of donepezil daily, respectively. Patients who initially received 1.5 mg of oral rivastigmine required a shorter time to reach a stable dose compared with those who initiated treatment at a higher dose of rivastigmine. Patients at a stable dose of 4.5 or 6 mg of rivastigmine were observed to persist longer than those at a lower dose of rivastigmine and donepezil.

Discussion

Although results indicate significant difference in persistence between rivastigmine and donepezil groups, clinical significance remains undetermined.

Long-Term Storage Effects on Stability of Aβ1-40, Aβ1-42, and Total Tau Proteins in Human Plasma Samples Measured with Immunomagnetic Reduction Assays

Background

The stability of Alzheimer's disease (AD) biomarkers in plasma, measured by immunomagnetic reduction (IMR) after long-term storage at −80°C, has not been established before.

Method

Ninety-nine human plasma samples from 53 normal controls (NCs), 5 patients with amnestic mild cognitive impairment (aMCI), and 41 AD patients were collected. Each plasma sample was aliquoted and stored as single-use aliquots at −80°C. The baseline measurements for Aβ_1–40, Aβ_1–42, and total Tau protein (T-Tau) concentrations for each sample were done within 3 months of blood draw by IMR. They are referred to as baseline concentrations. A separate aliquot from each sample was assayed with IMR to assess the stability of the measured analytes during storage at −80°C between 1.1 and 5.4 years. This is referred to as a repeated result.

Results

IMR shows that plasma levels of Aβ_1–40 and Aβ_1–42 exhibit stability over 5-year storage at −80°C and that plasma levels of T-Tau are less stable (approximately 1.5 years).

Conclusion

Although the measured concentrations of T-Tau in human plasma may alter during storage, the diagnostic utility of the results are only slightly affected when the product of Aβ_1–42 and T-Tau concentrations are used. The results show that the overall agreement between baseline and repeated measurements in the ability of discriminating NCs from aMCI/AD patients is higher than 80%.

Retinal ganglion cell-inner plexiform layer thickness is nonlinearly associated with cognitive impairment in the community-dwelling elderly

Introduction

Thinning of optical coherence tomography-measured retinal nerve fiber layer thickness and ganglion cell-inner plexiform layer (GC-IPL) thickness has been found in patients with Alzheimer's disease. However, the association of these retinal markers and cognition in nondemented elders may not be linear.

Methods

This cross-sectional study included 227 community-dwelling elders (age 65+ years). Multivariable regression analyses were performed to investigate the association between retinal nerve fiber layer/GC-IPL and global/domain-specific cognition.

Results

The performance of global cognition decreased as mean GC-IPL of bilateral eyes deviated from the sample mean (77.5 μm) (quadratic GC-IPL: β = -0.49 × 10^-2; 95% confidence interval: -0.74 × 10^-2 to -0.23 × 10^-2). Similar associations were also found for logical memory. No significant association was observed between retinal nerve fiber layer and cognition.

Discussion

Either thinning or thickening of GC-IPL was associated with poor cognition in nondemented elderly (a U-shaped association). GC-IPL may serve as a noninvasive preclinical predictor of Alzheimer's disease.

Diagnostic accuracy of Instrumental Activities of Daily Living for dementia in community-dwelling older adults

BACKGROUND

many people living with dementia remain underdiagnosed and unrecognised. Screening strategies are important for early detection.

OBJECTIVE

to examine whether the Lawton's Instrumental Activities of Daily Living (IADL) scale, compared with other cognitive screening tools-the Mini-Mental State Examination (MMSE), and the Ascertain Dementia 8-item Informant Questionnaire (AD8)-can identify older (≥ 65 years) adults with dementia.

DESIGN

population-based cross-sectional observational study.

SETTING

all 19 counties in Taiwan.

PARTICIPANTS

community-dwelling older adults (n = 10,340; mean age 74.87 ± 6.03).

METHODS

all participants underwent a structured in-person interview. Dementia was identified using National Institute on Aging-Alzheimer's Association core clinical criteria for all-cause dementia. Receiver operator characteristic curves were used to determine the discriminant abilities of the IADL scale, MMSE and AD8 to differentiate participants with and without dementia.

RESULTS

we identified 917 (8.9%) participants with dementia, and 9,423 (91.1%) participants without. The discriminant abilities of the MMSE, AD8 and IADL scale (cutoff score: 6/7; area under curve = 0.925; sensitivity = 89%; specificity = 81%; positive likelihood ratio = 4.75; accuracy = 0.82) were comparable. Combining IADL with AD8 scores significantly improved overall accuracy: specificity = 93%; positive likelihood ratio = 11.74; accuracy = 0.92.

CONCLUSIONS

our findings support using IADL scale to screen older community-dwelling residents for dementia: it has discriminant power comparable to that of the AD8 and MMSE. Combining the IADL and the AD8 improves specificity.

The Relation Between Brain Amyloid Deposition, Cortical Atrophy, and Plasma Biomarkers in Amnesic Mild Cognitive Impairment and Alzheimer's Disease

Background: Neuritic plaques and neurofibrillary tangles are the pathological hallmarks of Alzheimer’s disease (AD), while the role of brain amyloid deposition in the clinical manifestation or brain atrophy remains unresolved. We aimed to explore the relation between brain amyloid deposition, cortical thickness, and plasma biomarkers.

Methods: We used ¹¹C-Pittsburgh compound B-positron emission tomography to assay brain amyloid deposition, magnetic resonance imaging to estimate cortical thickness, and an immunomagnetic reduction assay to measure plasma biomarkers. We recruited 39 controls, 25 subjects with amnesic mild cognitive impairment (aMCI), and 16 subjects with AD. PiB positivity (PiB+) was defined by the upper limit of the 95% confidence interval of the mean cortical SUVR from six predefined regions (1.0511 in this study).

Results: All plasma biomarkers showed significant between-group differences. The plasma Aβ₄₀ level was positively correlated with the mean cortical thickness of both the PiB+ and PiB- subjects. The plasma Aβ₄₀ level of the subjects who were PiB+ was negatively correlated with brain amyloid deposition. In addition, the plasma tau level was negatively correlated with cortical thickness in both the PiB+ and PiB- subjects. Moreover, cortical thickness was negatively correlated with brain amyloid deposition in the PiB+ subjects. In addition, the cut-off point of plasma tau for differentiating between controls and AD was higher in the PiB- group than in the PiB+ group (37.5 versus 25.6 pg/ml, respectively). Lastly, ApoE4 increased the PiB+ rate in the aMCI and control groups.

Conclusion: The contributions of brain amyloid deposition to cortical atrophy are spatially distinct. Plasma Aβ₄₀ might be a protective indicator of less brain amyloid deposition and cortical atrophy. It takes more tau pathology to reach the same level of cognitive decline in subjects without brain amyloid deposition, and ApoE4 plays an early role in amyloid pathogenesis.

The effect of lifestyle on late-life cognitive change under different socioeconomic status

This study aimed to identify lifestyle factors associated with cognitive change and to explore whether the effect of lifestyle varies by socioeconomic status (SES). Participants aged 65 years and older were recruited from elderly health checkup programs from 2011 to 2013 in Taiwan. Neuropsychological tests, including tests of global cognition, logical memory, executive function, verbal fluency and attention, were administered at baseline (N = 603) and 2 years later (N = 509). After literature review, 9 lifestyle factors and 3 SES indicators were chosen and their effects on cognitive change were evaluated using linear regression adjusting for age, sex, education, APOE ε4 status, and baseline cognitive score. Five lifestyle factors (high vegetable and fish intake, regular exercise, not smoking, and light to moderate alcohol consumption) and 3 SES indicators [annual household income (> 33,333 USD vs. less), occupational complexity (high vs. low mental demanding job), and years of education (> 12 years vs. less)] were found to be protective against cognitive decline (P < 0.1 in any cognitive domains, ß ranging from 0.06 to 0.38). After further adjusting for all the lifestyle and SES factors, fish intake, higher income and occupational complexity remained protective. Significant interactions were found between a healthful lifestyle (defined as having ≥ 3 healthful lifestyle factors) and income on changes of global cognition and verbal fluency (P_interaction = 0.02 and 0.04). The protective effect of a healthful lifestyle was observed only among participants with lower income in global cognition and logical memory [ß = 0.17, 95% confidence interval (CI) = 0.07–0.26; ß = 0.30, 95% CI = 0.14–0.46]. To the best of our knowledge, this study for the first time explored how the interactions of lifestyle and SES affect cognitive change. Our findings will aid in developing dementia prevention programs and reduce health inequalities.