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Background: The associations between small vessel disease (SVD) and cerebrospinal amyloid-β1-42 (Aβ1-42) pathology have not been well-elucidated. Objective: Baseline (BL) white matter hyperintensities (WMH) were examined for associations with month-24 (M24) and longitudinal Aβ1-42 change in cognitively normal (CN) subjects. The interaction of WMH and Aβ1-42 on memory and executive function were also examined. Methods: This study included 72 subjects from the Alzheimer’s Disease Neuroimaging Initiative. Multivariable linear regression models evaluated associations between baseline WMH/intracranial volume ratio, M24 and change in Aβ1-42 over two years. Linear mixed effects models evaluated interactions between BL WMH/ICV and Aβ1-42 on memory and executive function. Results: Mean age of the subjects (Nmales = 36) = 73.80 years, SD = 6.73; mean education years = 17.1, SD = 2.4. BL WMH was significantly associated with M24 Aβ1-42 (p = 0.008) and two-year change in Aβ1-42 (p = 0.006). Interaction between higher WMH and lower Aβ1-42 at baseline was significantly associated with worse memory at baseline and M24 (p = 0.003). Conclusion: BL WMH was associated with M24 and longitudinal Aβ1-42 change in CN. The interaction between higher WMH and lower Aβ1-42 was associated with poorer memory. Since SVD is associated with longitudinal Aβ1-42 pathology, and the interaction of both factors is linked to poorer cognitive outcomes, the mitigation of SVD may be correlated with reduced amyloid pathology and milder cognitive deterioration in Alzheimer’s disease.

Background: Mild behavioral impairment (MBI) describes persistent behavioral changes in later life as an at-risk state for dementia. While cardiovascular risk factors (CVRFs) are linked to dementia, it is uncertain how CVRFs are associated with MBI. Objective: To determine the prevalence of MBI and its association with CVRFs among cognitively normal (CN) and mild cognitive impairment (MCI) individuals in Singapore. Methods: 172 individuals (79 CN and 93 MCI) completed the MBI-checklist (MBI-C). The prevalence of MBI and MBI-C sub-domain characteristics among CN and MCI were examined. Regression models evaluated the relationships between MBI-C sub-domain scores with CVRFs. Results: The prevalence of MBI and mean MBI-C total score were significantly higher among MCI than CN (34.4%versus 20.3%, p = 0.022 and 7.01 versus 4.12, p = 0.04). The highest and lowest-rated sub-domains among CN and MCI were impulse dyscontrol and abnormal thoughts and perception respectively. Within the MCI cohort, a higher proportion of individuals with diabetes mellitus (DM) had MBI compared to individuals without DM (28.1%versus 10.4%, p = 0.025). The interaction of DM and MCI cohort resulted in significantly higher mean MBI-C total, decreased motivation, emotional dysregulation, impulse dyscontrol, and abnormal thoughts and perception sub-domain scores. Conclusion: The prevalence of MBI is higher among a Singapore cohort compared to Caucasian cohorts. The associations of DM with both the presence and severity of MBI among MCI suggest that DM may be a risk factor for MBI. The optimization of DM may be a potential therapeutic approach to improve clinical outcomes among MCI with MBI.

Background Mild Behavioural Impairment (MBI) is a neurobehavioral syndrome characterized by later‐life emergent and sustained neuropsychiatric symptoms that is associated with higher risk of incident cognitive decline and dementia. While MBI is common in both subjective and mild cognitive impairment (MCI), most findings are based on Caucasians and the literature of MBI among Asians remains sparse. Here, we aim to investigate the frequency of MBI and its relationship with cognition, sleep and mood symptoms among cognitively intact (CN) and MCI Asians. Method 162 subjects (80 CN and 82 MCI) with a Clinical Dementia Rating of 0 or 0.5 were recruited from an outpatient neurology clinic (National Neuroscience Institute, Singapore). All subjects were administered a comprehensive neuropsychological assessment, the Pittsburgh Sleep Quality Index (PSQI) and the MBI‐checklist (MBI‐C). The presence of MBI was determined based on published cut‐offs of 6.5 for MCI and 8.5 for CN. Regression models evaluated the relationships between MBI and cognition, sleep and mood. Result 29 out of 162 subjects (17.9%) had MBI (28.0% of MCI and 7.5% of CN). Subjects with MBI had poorer global cognition (p=.029) and attention/working memory (p=.049). Specifically, we found that interest and impulse control subdomains of the MBI‐C were associated with poorer performance on the global cognition tests. In addition, those with MBI had sleep‐related daytime dysfunction (p=.008), poorer GDS and DASS scores (p<.01 or p<.001). Conclusion MBI in common among our Asian cohort and is associated with poorer cognitive performance, sleep and mood symptoms. Our findings further support the utility of MBI in clinical practice to identify individuals with early presentation of neurodegenerative diseases so as to provide a window of opportunity for early interventions to improve clinical outcomes.

Background There are 6000‐7000 stroke survivors yearly in Singapore with about 40% being at risk for post‐stroke cognitive impairment (PSCI). Stroke Memory Rehabilitation (SMaRT) programme was designed to reduce the incidence of PSCI, facilitate transition back to the community, improve the mood and quality of life of patients with mild ischemic strokes. We report the preliminary outcomes of the program. Method Participants who attended the programme from April 2018 to Dec 2019 were included in this study. Each patient attended 8 two‐hour sessions over 8 weeks, focusing on cognitive processes (episodic memory, executive function and visuospatial function); healthy lifestyle habits, relaxation techniques and goal setting. All patients were administered neuropsychological assessments and questionnaires pre‐programme, 8 weeks and 6 months post‐programme. Paired sample t‐tests were applied to evaluate the changes in scores over the four time points on each outcome measure, subject to Bonferroni correction for family‐wise errors. Result 156 participants (mean age=63.53 years, SD=9.63; mean education=9.95 years SD=4.18, 65.4 % male). Significant improvements in all outcome measures were observed from pre‐programme to all other time points. Cognitive scores significantly improved from pre to post‐programme and pre to 6 months post‐programme on the Montreal Cognitive Assessment (24.52 to 25.36; p<.001 and 25.05 to 25.98; p<.001 respectively); Visual Cognitive Assessment Test (VCAT) Score (22.67 to 24.14; p<.001 and 22.63 to 24.92; p<.001). Scores for Trail Making Test‐A only significantly shortened from pre‐ to 6 months post‐programme (52.00 to 45.52; p<.001). Depression levels significantly reduced on the Geriatric Depression Scale (4.01 to 3.29; p=.001 and 3.46 to 2.33; p<.001). Activities of daily living measured on the NEADL significantly improved (52.24 to 55.15; p<.001 and 52.48 to 56.27; p<.001). Quality of life (DemQOL) also significantly improved (88.77 to 91.88; p=.006 and 91.83 to 95.52; p<.001). Conclusion Preliminary findings demonstrate encouraging improvement in global cognition, executive function, quality of life, depression and activities of daily living from pre‐programme to 8 weeks and 6 months post‐programme. A multi‐approach structured cognitive rehabilitation programme for stroke survivors may thus be useful in preventing post‐stroke dementia.