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Background and purpose: Amyloid β (Aβ), a major biomarker of Alzheimer's disease, leads to tau accumulation, neurodegeneration and cognitive decline. Modelling the trajectory of Aβ accumulation in cognitively unimpaired (CU) individuals is crucial, as treatments targeting Aβ are anticipated. The evolution of Aβ levels was investigated to determine whether it could lead to classification into different groups by studying longitudinal Aβ changes in older CU individuals, and differences between the groups were compared. Methods: A total of 297 CU participants were included from the Alzheimer's Disease Neuroimaging Initiative database, and these participants underwent apolipoprotein E (APOE) genotyping, neuropsychological testing, brain magnetic resonance imaging, and an average of 3.03 follow‐up 18F‐florbetapir positron emission tomography scans. Distinct Aβ trajectory patterns were classified using latent class growth analysis, and longitudinal cognitive performances across these patterns were assessed with a linear mixed effects model. Results: The optimal model consisted of three classes, with a high entropy value of 0.947. The classes were designated as follows: class 1, non‐accumulation group (n = 197); class 2, late accumulation group (n = 70); and class 3, early accumulation group (n = 30). The late accumulation and early accumulation groups had more APOE ε4 carriers than the non‐accumulation group. The longitudinal analysis of cognitive performance revealed that the early accumulation group showed the steepest decline (modified Preclinical Alzheimer's Cognitive Composite with digit symbol substitution [mPACCdigit], p < 0.001; modified Preclinical Alzheimer's Cognitive Composite with trails B [mPACCtrailsB], p < 0.001) and the late accumulation group showed a steeper decline (mPACCdigit, p = 0.014; mPACCtrailsB, p = 0.007) compared to the non‐accumulation group. Conclusions: Our study showed the heterogeneity of Aβ accumulation trajectories in CU older individuals. The prognoses for cognitive decline differ according to the Aβ trajectory patterns. [ABSTRACT FROM AUTHOR]

Background: Alcohol withdrawal is widely recognized as a trigger for acute symptomatic seizures among individuals with chronic alcohol consumption. While most alcohol withdrawal seizures occur shortly after cessation, chronic alcohol consumption can be associated with the development of epilepsy, necessitating anti‐epileptic drug (AED) therapy. This study aimed to investigate the clinical characteristics, seizure recurrence, and epilepsy development in patients with alcohol‐related seizures and to identify prognostic factors for epilepsy. Methods: In a retrospective analysis at Ewha Womans University Mokdong Hospital, 206 patients with alcohol‐related seizures were examined and 15 were excluded due to preexisting epilepsy. Demographic and clinical data, including alcohol withdrawal duration, seizure recurrence, types, and comorbidities, were investigated. Logistic regression models were used to analyze the risk factors for seizure recurrence and epilepsy development. The performance of the final models was evaluated based on the area under the receiver operating characteristic curve (AUC) and validated using calibration plots and leave‐one‐out cross‐validation. Results: Of the 191 patients (146 males; mean age 48.3 ± 12.1 years) with alcohol‐related seizures, 99 patients (51.8%) experienced seizure recurrence and 79 patients (41.4%) developed epilepsy. Factors associated with seizure recurrence included alcohol consumption levels, occurrence of focal impaired awareness seizure, anxiety, and headache. The number of recurrent seizures, semiology, status epilepticus, electroencephalogram findings, and brain imaging findings was associated with epilepsy development. The predictive models showed strong diagnostic performance, with AUCs of 0.833 for seizure recurrence and 0.939 for epilepsy development. Conclusion: High alcohol consumption and specific clinical and diagnostic features are significant predictors of seizure recurrence and the development of epilepsy among patients with alcohol‐related seizures. These findings underscore the importance of early identification and intervention to prevent seizure recurrence and the onset of epilepsy, emphasizing the importance of AED treatment in managing these conditions. [ABSTRACT FROM AUTHOR]

INTRODUCTION: We investigated the prevalence of amyloid beta (Aβ) positivity (+) and cognitive trajectories in Koreans and non‐Hispanic Whites (NHWs). METHODS: We included 5121 Koreans from multiple centers across South Korea and 929 NHWs from the Alzheimer's Disease Neuroimaging Initiative (ADNI). Participants underwent Aβ positron emission tomography and were categorized into cognitively unimpaired (CU), mild cognitive impairment (MCI), and dementia stages. Age, sex, education, and apolipoprotein E. genotype were adjusted using multivariable logistic regression and stabilized inverse probability of treatment weights based on the propensity scores to mitigate imbalances in these variables. RESULTS: The prevalence of Aβ+ was lower in CU Koreans than in CU NHWs (adjusted odds ratio 0.60). Aβ+ Koreans showed a faster cognitive decline than Aβ+ NHWs in the CU (B = −0.314, p =.004) and MCI stages (B = −0.385, p <.001). DISCUSSION: Ethnic characteristics of Aβ biomarkers should be considered in research and clinical application of Aβ‐targeted therapies in diverse populations. Highlights: Koreans have a lower prevalence of Aβ positivity compared to NHWs in the CU stage.The effects of Alzheimer's risk factors on Aβ positivity differ between Koreans and NHWs.Aβ‐positive (Aβ+) Koreans show faster cognitive decline than Aβ+ NHWs in the CU and MCI stages. [ABSTRACT FROM AUTHOR]

Objective: We investigated whether hippocampal perfusion changes are associated with cognitive decline, motor deficits, and the risk of dementia conversion in patients with Parkinson disease (PD). Methods: We recruited patients with newly diagnosed and nonmedicated PD and healthy participants who underwent dual phase 18F‐N‐(3‐fluoropropyl)‐2β‐carboxymethoxy‐3β‐(4‐iodophenyl) nortropane positron emission tomography scans. Patients were classified into 3 groups according to hippocampal perfusion measured by standard uptake value ratios (SUVRs): (1) PD hippocampal hypoperfusion group (1 standard deviation [SD] below the mean hippocampal SUVR of healthy controls; PD‐hippo‐hypo), (2) PD hippocampal hyperperfusion group (1 SD above the mean; PD‐hippo‐hyper), and (3) the remaining patients (PD‐hippo‐normal). We compared the baseline cognitive performance, severity of motor deficits, hippocampal volume, striatal dopamine transporter (DAT) availability, and risk of dementia conversion among the groups. Results: We included 235 patients (PD‐hippo‐hypo, n = 21; PD‐hippo‐normal, n = 157; PD‐hippo‐hyper, n = 57) and 48 healthy participants. Patients in the PD‐hippo‐hypo group were older and had smaller hippocampal volumes than those in the other PD groups. The PD‐hippo‐hypo group showed less severely decreased DAT availability in the putamen than the other groups despite similar severities of motor deficit. The PD‐hippo‐hypo group had a higher risk of dementia conversion compared to the PD‐hippo‐normal (hazard ratio = 2.59, p = 0.013) and PD‐hippo‐hyper (hazard ratio = 3.73, p = 0.006) groups, despite similar cognitive performance at initial assessment between groups. Interpretation: Hippocampal hypoperfusion may indicate a reduced capacity to cope with neurodegenerative processes in terms of the development of motor deficits and cognitive decline in patients with PD. ANN NEUROL 2024;95:388–399 [ABSTRACT FROM AUTHOR]

Background: Early detection of β‐amyloid (Aβ) accumulation, a major biomarker for Alzheimer's disease (AD), has become important. While Aβ deposition can be detected by positron emission tomography (PET), practical fluid Aβ biomarker is also being developed recently. In the present study, we aimed to determine whether APOE genotypes, age, and cognitive status increase the predictive performance of fluid Aβ levels for amyloid PET positivity. Methods: We recruited 488 participants who underwent both plasma Aβ and Aβ PET studies (Cohort 1) and 217 participants who underwent both cerebrospinal fluid (CSF) Aβ and Aβ PET studies (Cohort 2). Plasma and CSF samples were analyzed using ABtest‐MS, an antibody‐free liquid chromatography‐differential mobility spectrometry‐triple quadrupole mass spectrometry method and INNOTEST enzyme‐linked immunosorbent assay kits, respectively. To evaluate the predictive performance of plasma Aβ and CSF Aβ, respectively, logistic regression and receiver operating characteristic analyses were performed. Results: When predicting Aβ PET status, both plasma Aβ42/40 ratio and CSF Aβ42 showed high accuracy (plasma Aβ area under the curve (AUC) 0.814; CSF Aβ AUC 0.848). In the plasma Aβ models, the AUC values were higher than plasma Aβ alone model, when the models were combined with either cognitive stage (p < 0.001) or APOE genotype (p = 0.011). On the other hand, there was no difference between the CSF Aβ models, when these variables were added. Conclusions: Plasma Aβ might be a useful predictor of Aβ PET status as much as CSF Aβ, particularly when considered with clinical information. [ABSTRACT FROM AUTHOR]