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Abstract Introduction Only two studies investigated the associations between peak width of skeletonized mean diffusivity (PSMD) and age‐related cognitive alterations, whereas none of the studies investigated the association with vascular risk factors. Methods We evaluated 801 stroke‐ and dementia‐free elderlies with baseline and 3‐year follow‐up assessments. Regression analyses were used to assess the association between age‐related cognitive functions and PSMD. Simple mediation models were used to study the mediation effect of PSMD between vascular risk factors and age‐related cognitive outcomes. Results PSMD was negatively associated with processing speed at baseline and negatively associated with processing and memory scores at 3‐year follow‐up. The association between vascular risk factors and age‐related cognition was mediated by PSMD, as well as other diffusion tensor imaging markers. Discussion PSMD is preferred over other diffusion tensor imaging markers as it is sensitive to age‐related cognitive alterations and calculation is fully automated. PSMD is proposed as a research tool to monitor age‐related cognitive alterations.

Early identification of cognitive impairment would allow affected patients to receive care at earlier stage. Changes in the arterial stiffness have been identified as a prominent pathological feature of dementia. This study aimed to verify if applying machine-learning analysis to spectral indices of the arterial pulse waveform can be used to discriminate different cognitive conditions of community subjects. 3-min Radial arterial blood pressure waveform (BPW) signals were measured noninvasively in 123 subjects. Eight machine-learning algorithms were used to evaluate the following 4 pulse indices for 10 harmonics (total 40 BPW spectral indices): amplitude proportion and its coefficient of variation; phase angle and its standard deviation. Significant differences were noted in the spectral pulse indices between Alzheimer’s-disease patients and control subjects. Using them as training data (AUC = 70.32% by threefold cross-validation), a significant correlation (R2 = 0.36) was found between the prediction probability of the test data (comprising community subjects at two sites) and the Mini-Mental-State-Examination score. This finding illustrates possible physiological connection between arterial pulse transmission and cognitive function. The present findings from pulse-wave and machine-learning analyses may be useful for discriminating cognitive condition, and hence in the development of a user-friendly, noninvasive, and rapid method for the early screening of dementia.

Early identification of cognitive impairment would allow affected patients to receive care at earlier stage. Changes in the arterial stiffness have been identified as a prominent pathological feature of dementia. This study aimed to verify if applying machine-learning analysis to spectral indices of the arterial pulse waveform can be used to discriminate different cognitive conditions of community subjects. 3-min Radial arterial blood pressure waveform (BPW) signals were measured noninvasively in 123 subjects. Eight machine-learning algorithms were used to evaluate the following 4 pulse indices for 10 harmonics (total 40 BPW spectral indices): amplitude proportion and its coefficient of variation; phase angle and its standard deviation. Significant differences were noted in the spectral pulse indices between Alzheimer's-disease patients and control subjects. Using them as training data (AUC = 70.32% by threefold cross-validation), a significant correlation (R2 = 0.36) was found between the prediction probability of the test data (comprising community subjects at two sites) and the Mini-Mental-State-Examination score. This finding illustrates possible physiological connection between arterial pulse transmission and cognitive function. The present findings from pulse-wave and machine-learning analyses may be useful for discriminating cognitive condition, and hence in the development of a user-friendly, noninvasive, and rapid method for the early screening of dementia. [ABSTRACT FROM AUTHOR]

Objective: There have been limited data available on the prevalence of structural brain abnormalities in asymptomatic individuals and a growing interest in the various ethical issues related to reporting of such findings. This study evaluated the prevalence of incidental abnormalities on brain magnetic resonance imaging (MRI) in a random sample of 60- to 64-year-old community-dwelling individuals as well as successfully followed a referral pathway taking into account of the various ethical issues related to the referral process. The Personality and Total Health (PATH) Project was designed to study the risk and protection factors of normal ageing, dementia and other neuropsychiatric disorders. Method: MRI scans were performed in randomly selected 478 healthy, community-dwelling 60- to 64-year-old individuals. All scans were reported for abnormalities by a radiologist. Results: Abnormalities were detected in 22 (4.8%) subjects, comprising 10 tumours (pituitary adenoma 4, meningioma 3, suprasellar tumour 1, cavernous haemangioma 1, subarachnoid lipoma 1), 6 infarct-like lesions, 2 arachnoid cysts, 1 possible normal pressure hydrocephalus, and 1 each of unconfirmed aneurysm and mesial temporal sclerosis. Further evaluation led to novel intervention in one case of pituitary adenoma, and adjustment of drug treatment to modify risk factors in two cases with subclinical infarction. Conclusion: While no case required immediate referral or urgent surgical intervention, the change in the outcome of treatment of some cases suggests that appropriate referral process should be in place when researchers study large number of subjects in the community using MRI of the brain. [ABSTRACT FROM AUTHOR]

Our purpose was to estimate the rate of carriage of vancomycin-resistant enterococci (VRE) in hospitalized patients in a district hospital and in healthy subjects in the community in Hong Kong. Rectal swabs were collected from all patients admitted to the intensive care unit, and stool specimens were collected from all patients presenting with suspected antibiotic-associated diarrhea over a 2-month period. Stool specimens were also collected from healthy subjects in the community. Specimens were enriched and cultured on selective media for the isolation of enterococci. All isolates were identified, and their minimum inhibitory concentration for vancomycin was determined. Susceptibility to other antibiotics was investigated. Samples yielded 125 isolates of enterococci, the majority of isolates being Enterococcus faecalis (75) and E. faecium (35). Nine of 11 strains of E. gallinarum and 2 of 2 strains of E. casseliflavus isolated from hospitalized patients were intermediately resistant to vancomycin, but no strains highly resistant to vancomycin were isolated. Resistance to other drugs, including the fluoroquinolones, was present, and a high-level resistance to gentamicin and streptomycin was found in 37% and 46% of strains, respectively. Colonization with VRE remains low in Hong Kong. This result is supported by the low level of isolation of VRE from infections in the region and may be attributable to low levels of vancomycin use. High-level aminoglycoside resistance and fluoroquinolone resistance are common, and continued monitoring for VRE is suggested. [ABSTRACT FROM AUTHOR]

Introduction: Only two studies investigated the associations between peak width of skeletonized mean diffusivity (PSMD) and age-related cognitive alterations, whereas none of the studies investigated the association with vascular risk factors., Methods: We evaluated 801 stroke- and dementia-free elderlies with baseline and 3-year follow-up assessments. Regression analyses were used to assess the association between age-related cognitive functions and PSMD. Simple mediation models were used to study the mediation effect of PSMD between vascular risk factors and age-related cognitive outcomes., Results: PSMD was negatively associated with processing speed at baseline and negatively associated with processing and memory scores at 3-year follow-up. The association between vascular risk factors and age-related cognition was mediated by PSMD, as well as other diffusion tensor imaging markers., Discussion: PSMD is preferred over other diffusion tensor imaging markers as it is sensitive to age-related cognitive alterations and calculation is fully automated. PSMD is proposed as a research tool to monitor age-related cognitive alterations., (© 2019 The Authors.)