Association of Glycemic Variability With Imaging Markers of Vascular Burden, ß-Amyloid, Brain Atrophy, and Cognitive Impairment.

BACKGROUND AND OBJECTIVE: We aimed to investigate the association between glycemic variability (GV) and neuroimaging markers of white matter hyperintensities (WMH), beta-amyloid (Aß), brain atrophy, and cognitive impairment. METHODS: This was a retrospective cohort study that included participants without dementia from a memory clinic. They all had Aß PET, brain MRI, and standardized neuropsychological tests and had fasting glucose (FG) levels tested more than twice during the study period. We defined GV as the intraindividual visit-to-visit variability in FG levels. Multivariable linear regression and logistic regression were used to identify whether GV was associated with the presence of severe WMH and Aß uptake with DM, mean FG levels, age, sex, hypertension, and presence of APOE4 allele as covariates. Mediation analyses were used to investigate the mediating effect of WMH and Aß uptake on the relationship between GV and brain atrophy and cognition. RESULTS: Among the 688 participants, the mean age was 72.2 years, and the proportion of female participants was 51.9%. Increase in GV was predictive of the presence of severe WMH (coefficient [95% CI] 1.032 [1.012-1.054]; p = 0.002) and increased Aß uptake (1.005 [1.001-1.008]; p = 0.007). Both WMH and increased Aß uptake partially mediated the relationship between GV and frontal-executive dysfunction (GV → WMH → frontal-executive; direct effect, -0.319 [-0.557 to -0.080]; indirect effect, -0.050 [-0.091 to -0.008]) and memory dysfunction (GV → Aß â†’ memory; direct effect, -0.182 [-0.338 to -0.026]; indirect effect, -0.067 [-0.119 to -0.015]), respectively. In addition, increased Aß uptake completely mediated the relationship between GV and hippocampal volume (indirect effect, -1.091 [-2.078 to -0.103]) and partially mediated the relationship between GV and parietal thickness (direct effect, -0.00101 [-0.00185 to -0.00016]; indirect effect, -0.00016 [-0.00032 to -0.000002]). DISCUSSION: Our findings suggest that increased GV is related to vascular and Alzheimer risk factors and neurodegenerative markers, which in turn leads to subsequent cognitive impairment. Furthermore, GV can be considered a potentially modifiable risk factor for dementia prevention.

Machine learning-based prediction of post-stroke cognitive status using electroencephalography-derived brain network attributes.

Objectives: More than half of patients with acute ischemic stroke develop post-stroke cognitive impairment (PSCI), a significant barrier to future neurological recovery. Thus, predicting cognitive trajectories post-AIS is crucial. Our primary objective is to determine whether brain network properties from electroencephalography (EEG) can predict post-stroke cognitive function using machine learning approach. Methods: We enrolled consecutive stroke patients who underwent both EEG during the acute stroke phase and cognitive assessments 3 months post-stroke. We preprocessed acute stroke EEG data to eliminate low-quality epochs, then performed independent component analysis and quantified network characteristics using iSyncBrain®. Cognitive function was evaluated using the Montreal cognitive assessment (MoCA). We initially categorized participants based on the lateralization of their lesions and then developed machine learning models to predict cognitive status in the left and right hemisphere lesion groups. Results: Eighty-seven patients were included, and the accuracy of lesion laterality prediction using EEG attributes was 97.0%. In the left hemispheric lesion group, the network attributes of the theta band were significantly correlated with MoCA scores, and higher global efficiency, clustering coefficient, and lower characteristic path length were associated with higher MoCA scores. Most features related to cognitive scores were selected from the frontal lobe. The predictive powers (R-squared) were 0.76 and 0.65 for the left and right stroke groups, respectively. Conclusion: Estimating EEG-based network properties in the acute phase of ischemic stroke through a machine learning model has a potential to predict cognitive outcomes after ischemic stroke.

Stress cardiomyopathy associated with area postrema syndrome as a presentation of neuromyelitis optica: case report.

BACKGROUND: Stress cardiomyopathy (Takotsubo cardiomyopathy) is very rare in the central nervous system (CNS) demyelinating disorders. Although this dysfunction of the heart-brain axis has been reported in several case series related to multiple sclerosis (MS), stress cardiomyopathy by neuromyelitis optica (NMO), which is rarer CNS demyelinating disorder than MS, is extremely rare. Herein, we report a case of stress cardiomyopathy associated with a medullary lesion as a presentation of NMO. CASE PRESENTATION: A 30-year-old woman was treated by veno-arterial extracorporeal membrane oxygenation due to catastrophic cardiopulmonary dysfunction after prolonged and unexplained nausea, vomiting, and cough. Myoclonus on the limbs developed afterward. Taken with suspicion of area postrema syndrome (APS), the brain MRI showed a demyelinating lesion in the medulla oblongata. APS and severe heart failure by stress cardiomyopathy were completely resolved by ECMO and hydrocortisone therapy. However, the CNS demyelinating lesion recurred after 1 month. The patient was diagnosed with NMO evident by the presence of aquaporin-4 antibody; Steroid therapy improved her symptoms. CONCLUSION: NMO should be considered as one of the differential diagnoses in patients with APS preceding severe cardiopulmonary distress.

Early Impairment of Chopsticks Skills in Parkinsonism Suggests Progressive Supranuclear Palsy.

BACKGROUND AND PURPOSE: Chopsticks are a primary eating utensil in East Asia, but systematic assessments of chopsticks skills in parkinsonian disorders is lacking. We aimed to identify any differences in chopsticks skills in the early stages of Parkinson's disease (PD) and atypical parkinsonism (AP), including progressive supranuclear palsy (PSP), multiple system atrophy (MSA), and corticobasal syndrome (CBS). METHODS: We consecutively recruited 111 patients with PD and 74 with AP (40 with PSP, 30 with MSA, and 4 with CBS) who were in a drug-naïve state. The motor and cognitive functions of the patients were evaluated using a standardized protocol. Everyday chopsticks skills were evaluated using a chopsticks questionnaire developed in-house. The chopsticks skills test (CST) involved counting the number of pills that the subject was able to carry using chopsticks between two dishes separated by 20 cm within 20 seconds. RESULTS: Patient responses to the questionnaire indicating poor chopsticks skills ("I cannot pick up some of the food items" or "I cannot use chopsticks anymore") were present in 23.0% of AP patients and 30% of PSP patients, compared to only 5.6% of PD patients [odd ratio (OR)=5.07 and OR=7.29, p≤0.001 in both]. The performance in the CST was worse in PSP than in PD (p<0.001). The CST results were correlated with hand motor skills including in the coinrotation test, timed figure-tapping test, and motor Unified Parkinson's Disease Rating Scale scores in all of the patient groups (p<0.001). In PSP, a decline in visuospatial function and frontal executive function was associated with a poor performance in the CST in addition to poor motor performance (p<0.05). CONCLUSIONS: Impairments in chopsticks skills were more common in PSP than in PD during the early stages of parkinsonism. This suggests that early functional impairment of chopsticks skills can be used as a warning sign for PSP.