Low serum serotonin is associated with functional decline, mild behavioural impairment and brain atrophy in dementia-free subjects.

Brain serotonin dysregulation is associated with dementia and neuropsychiatric symptomology. However, the prognostic utility of circulating serotonin levels in detecting features of prodromal dementia including functional decline, cognitive impairment, mild behavioural impairment and brain atrophy remains unclear. In this prospective study of memory clinic subjects followed-up for ≤5 years, dementia-free subjects, classified as having no cognitive impairment or cognitive impairment, no dementia at baseline, underwent annual neuropsychological assessments including Montreal Cognitive Assessment, Global Cognition scores and Clinical Dementia Rating Scale Global Scores (where a ≥ 0.

Clinical utility of plasma p-tau217 in identifying abnormal brain amyloid burden in an Asian cohort with high prevalence of concomitant cerebrovascular disease.

Introduction: Using an Asian cohort with high prevalence of concomitant cerebrovascular disease (CeVD), we evaluated the performance of a plasma immunoassay for tau phosphorylated at threonine 217 (p-tau217) in detecting amyloid beta positivity (Aβ+) on positron emission tomography and cognitive decline, based on a three-range reference, which stratified patients into low-, intermediate-, and high-risk groups for Aβ+.

Methods: Brain amyloid status (Aβ- [n = 142] vs Aβ+ [n = 73]) on amyloid PET scans was assessed along with the plasma ALZpath p-tau217 assay to derive three-range reference points for PET Aβ+ based on 90% sensitivity (lower threshold) and 90% specificity (upper threshold).

Results: Plasma p-tau217 (area under the curve [AUC] = 0.

Additive effects of cerebrovascular disease functional connectome phenotype and plasma p-tau181 on longitudinal neurodegeneration and cognitive outcomes.

Introduction: We investigated the effects of multiple cerebrovascular disease (CeVD) neuroimaging markers on brain functional connectivity (FC), and how such CeVD-related FC changes interact with plasma phosphorylated tau (p-tau)181 (an Alzheimer's disease [AD] marker) to influence downstream neurodegeneration and cognitive changes.

Methods: Multivariate associations among four CeVD markers and whole-brain FC in 529 participants across the dementia spectrum were examined using partial least squares correlation. Interactive effects of CeVD-related FC patterns and p-tau181 on longitudinal gray matter volume (GMV) and cognitive changes were investigated using linear mixed-effects models.

Associations of Circulating Platelet Endothelial Cell Adhesion Molecule-1 Levels With Progression of Cerebral Small-Vessel Disease, Cognitive Decline, and Incident Dementia.

Background: The association between platelet endothelial cell adhesion molecule-1 (PECAM-1) with cerebral small-vessel disease and cognition in dementia-free subjects remains uninvestigated.

Methods And Results: A prospective cohort of dementia-free subjects was recruited from memory clinics and followed up for 5 years. Annual neurocognitive assessments and twice-yearly brain magnetic resonance imaging scans were performed.

Serum Placental Growth Factor as a Marker of Cerebrovascular Disease Burden in Alzheimer's Disease.

Background: Concomitant cerebrovascular diseases (CeVD) have been identified as an important determinant of Alzheimer's disease (AD) progression. Development of robust blood-based biomarkers will provide critical tools to evaluate prognosis and potential interventional strategies for AD with CeVD.

Objective: This study investigated circulating placental growth factor (PlGF), a potent pro-angiogenic factor related to endothelial dysfunction and vascular inflammation, in an Asian memory clinic cohort of non-demented individuals as well as AD, including its associations with neuroimaging markers of CeVD.

Detection of Bacterial Neutral Ceramidase in Diabetic Foot Ulcers with an Optimized Substrate and Chemoenzymatic Probes.

Ceramidases (CDases) are important in controlling skin barrier integrity by regulating ceramide composition and affording downstream signal molecules. While the functions of epidermal CDases are known, roles of neutral CDases secreted by skin-residing microbes are undefined. Here, we developed a one-step fluorogenic substrate, S-B, for specific detection of bacterial CDase activity and inhibitor screening.

Associations of Blood Cardiovascular Biomarkers With Brain Free Water and Its Relationship to Cognitive Decline: A Diffusion-MRI Study.

Background And Objectives: There is an increasing awareness of the "Heart-Brain Connection," whereby cardiovascular function is connected with cognition. Diffusion-MRI studies reported higher brain free water (FW) was associated with cerebrovascular disease (CeVD) and cognitive impairment. In this study, we investigated whether higher brain FW was related to blood cardiovascular biomarkers and whether FW mediated the associations between blood biomarkers and cognition.

Qualitative study exploring heterogeneity in caregiving experiences post-stroke in Singapore.

Objective: Stroke, a common illness in older adults, accounts for up to 4% of direct medical costs in developed nations. Informal caregiving contributing a significant proportion of economic burden post-stroke warrants a deeper understanding of the caregiving context to sustain caregiving arrangement. While literature exists describing differences in motivation and preferences of caregivers, limited literature explores differences in caregiving experiences of different types of caregivers (ie, spouse, adult-child, sibling or others).

Serum Cathepsin D Is a Potential Biomarker for Alzheimer's Disease Dementia and Cognitive Decline.

Background: The lysosomal protease cathepsin D (catD) has been reported to be upregulated in postmortem Alzheimer's disease (AD) cortex, where it colocalized with neurofibrillary tangles and correlated with levels of phosphorylated tau, suggesting pathophysiological links between catD and neurodegeneration. In contrast, studies of serum catD in AD have yielded conflicting results, and potential associations between baseline serum catD and functional outcomes of patients are at present unknown.

Objective: We aimed to examine the status of serum catD in a Singapore-based longitudinal study of dementia and investigate catD associations with functional and cognitive decline.

Deep-learning retinal vessel calibre measurements and risk of cognitive decline and dementia.

Previous studies have explored the associations of retinal vessel calibre, measured from retinal photographs or fundus images using semi-automated computer programs, with cognitive impairment and dementia, supporting the concept that retinal blood vessels reflect microvascular changes in the brain. Recently, artificial intelligence deep-learning algorithms have been developed for the fully automated assessment of retinal vessel calibres. Therefore, we aimed to determine whether deep-learning-based retinal vessel calibre measurements are predictive of risk of cognitive decline and dementia.

Age-Related Eye Diseases in Individuals With Mild Cognitive Impairment and Alzheimer's Disease.

Introduction: Alzheimer's disease (AD) and age-related eye diseases pose an increasing burden as the world's population ages. However, there is limited understanding on the association of AD/cognitive impairment, no dementia (CIND) with age-related eye diseases.

Methods: In this cross-sectional, memory clinic-based study of multiethnic Asians aged 50 and above, participants were diagnosed as AD ( = 216), cognitive impairment, no dementia (CIND) ( = 252), and no cognitive impairment (NCI) ( = 124) according to internationally accepted criteria.

Association Between Cerebral Cortical Microinfarcts and Perilesional Cortical Atrophy on 3T MRI.

Background And Objectives: Cerebral cortical microinfarcts (CMIs) are a novel MRI marker of cerebrovascular disease (CeVD) that predicts accelerated cognitive decline. Presence of CMIs is known to be associated with global cortical atrophy, although the mechanism linking the two is unclear. Our primary objective was to examine the relation between CMIs and cortical atrophy and to establish possible perilesional atrophy surrounding CMIs.

Alzheimer's Disease THErapy With NEuroaid (ATHENE): A Randomized Double-Blind Delayed-Start Trial.

Objectives: Preclinical and clinical studies indicate a role for MLC901 (NeuroAiD II) in Alzheimer's disease (AD). The primary aim was to investigate its safety as add-on therapy to standard treatment and the secondary aims its effect on cognition and slowing disease progression.

Design: Randomized double-blind placebo-controlled delayed-start study.

A wireless and battery-free wound infection sensor based on DNA hydrogel.

The confluence of wireless technology and biosensors offers the possibility to detect and manage medical conditions outside of clinical settings. Wound infections represent a major clinical challenge in which timely detection is critical for effective interventions, but this is currently hindered by the lack of a monitoring technology that can interface with wounds, detect pathogenic bacteria, and wirelessly transmit data. Here, we report a flexible, wireless, and battery-free sensor that provides smartphone-based detection of wound infection using a bacteria-responsive DNA hydrogel.

Seeking healthcare services post-stroke: a qualitative descriptive study exploring family caregiver and stroke survivor perspectives in an asian setting.

Aim: Exploration of the healthcare journey post-stroke is incomplete without acknowledging the crucial role of family caregivers. With limited literature documenting the role of caregivers in the healthcare journey post-stroke, we aimed to describe the healthcare experiences of family caregivers and stroke survivors across different caregiver identities in Singapore.

Methods: We conducted a qualitative descriptive study involving semi-structured interviews with transcripts analysed using thematic analysis.

Burden of informal care in stroke survivors and its determinants: a prospective observational study in an Asian setting.

Background: Informal caregiving is an integral part of post-stroke recovery with strenuous caregiving demands often resulting in caregiving burden, threatening sustainability of caregiving and potentially impacting stroke survivor's outcomes. Our study aimed to examine and quantify objective and subjective informal care burden after stroke; and to explore the factors associated with informal care burden in Singapore.

Methods: Stroke patients and their informal caregivers were recruited from all five tertiary hospitals in Singapore from December 2010 to September 2013.

Support system diversity among family caregivers of stroke survivors: a qualitative study exploring Asian perspectives.

Background: Caregiving is a global phenomenon which is bound to increase in tandem with the aging population worldwide. Stroke is a condition common in older people that requires complex caregiving necessitating provision of adequate support to the caregivers. Past literature consists of limited accounts of types and organization of support arrangements needed by different caregivers.

Role of caregiver factors in outpatient medical follow-up post-stroke: observational study in Singapore.

Background: Outpatient medical follow-up post-stroke is not only crucial for secondary prevention but is also associated with a reduced risk of rehospitalization. However, being voluntary and non-urgent, it is potentially determined by both healthcare needs and the socio-demographic context of stroke survivor-caregiver dyads. Therefore, we aimed to examine the role of caregiver factors in outpatient medical follow-up (primary care (PC) and specialist outpatient care (SOC)) post-stroke.

Stroke Rehabilitation Use and Caregiver Psychosocial Health Profiles in Singapore: A Latent Profile Transition Analysis.

Objectives: To identify and describe caregiver profiles based on their psychosocial health characteristics over a 12-month period and transitions among these profiles, to determine if stroke rehabilitation use at 12 months post-stroke differed by caregiver profile transition patterns, and to investigate if caregiver profiles at 3 months post-stroke moderate the association of stroke rehabilitation use at 3 months and 12 months post-stroke after accounting for covariates.

Design: Latent profile transition analysis of caregiver psychosocial health with stroke rehabilitation use at 12 month post-stroke as outcome.

Setting And Participants: A total of 149 stroke patient-caregiver dyads from the Singapore Stroke Study.

Plasma osteopontin as a biomarker of Alzheimer's disease and vascular cognitive impairment.

Cerebrovascular disease (CeVD) and neurodegenerative dementia such as Alzheimer's disease (AD) are frequently associated comorbidities in the elderly, sharing common risk factors and pathophysiological mechanisms including neuroinflammation. Osteopontin (OPN) is an inflammatory marker found upregulated in vascular diseases as well as in AD. However, its involvement in vascular dementia (VaD) and pre-dementia stages, namely cognitive impairment no dementia (CIND), both of which fall under the spectrum of vascular cognitive impairment (VCI), has yet to be examined.

Primary Care Prognostic (PCP) Index of 11-Year Mortality Risk: Development and Validation of a Brief Prognostic Tool.

Background: Healthcare providers use a life expectancy of at least 5 to 10 years in shared clinical decision-making with older adults about cancer screening, major surgeries, and disease prevention interventions. At present, few prognostic indexes predict long-term mortality beyond 10 years or are suited for use in primary care settings.

Objective: We developed and validated an 8-item multidimensional index predicting 11-year mortality for use in primary care.