Publications by authors named "Dong-Won Yang"

Introduction: Alzheimer's disease (AD) is now diagnosed biologically. Since subjective cognitive decline (SCD) may indicate preclinical AD, assessing AD-biomarkers is crucial. We investigated cognitive and neurodegenerative trajectories in SCD over 24 months based on biomarker positivity, and evaluated the predictive value of plasma biomarkers.

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Lecanemab (product name Leqembi®) is an anti-amyloid monoclonal antibody treatment approved for use in Korea for patients with mild cognitive impairment (MCI) or mild dementia due to Alzheimer's disease. The Korean Dementia Association has created recommendations for the appropriate use of lecanemab to assist clinicians. These recommendations include selecting patients for administration, necessary pre-administration tests and preparations, administration methods, monitoring for amyloid related imaging abnormalities (ARIA), and communication with patients and caregivers.

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Background And Purpose: To ensure data privacy, the development of defacing processes, which anonymize brain images by obscuring facial features, is crucial. However, the impact of these defacing methods on brain imaging analysis poses significant concern. This study aimed to evaluate the reliability of three different defacing methods in automated brain volumetry.

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Background And Purpose: Alzheimer's disease (AD) is a neurodegenerative disease characterized by a progressive decline in cognition and performance of daily activities. Recent studies have attempted to establish the relationship between AD and sleep. It is believed that patients with AD pathology show altered sleep characteristics years before clinical symptoms appear.

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Purpose: Telomerase activation, a critical step in cancer progression, occurs in approximately 95% of breast cancer cases. Telomerase is an attractive therapeutic target for breast cancer owing to its unique expression pattern. GV1001, a telomerase-derived peptide, is loaded onto human leukocyte antigen (HLA) class II antigen-presenting cells and binds to CD4+ T cell activating immune responses.

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Background: Subjective cognitive decline (SCD) refers to the self-reported persistent cognitive decline despite normal objective testing, increasing the risk of dementia compared to cognitively normal individuals.

Objective: This study aims to investigate the attributes of SCD patients who demonstrated memory function improvement.

Methods: In this prospective study of SCD, a total of 120 subjects were enrolled as part of a multicenter cohort study aimed at identifying predictors for the clinical progression to mild cognitive impairment or dementia (CoSCo study).

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Background: Subjective cognitive decline (SCD) is a risk factor for Alzheimer's disease (AD); however, the rates of cognitive decline are variable according to underlying pathologies and biomarker status. We conducted an observational study and aimed to investigate baseline characteristics and biomarkers related with cognitive declines in SCD. Our study also assessed whether SCD participants showed different cognitive and biomarker trajectories according to baseline amyloid deposition.

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Background And Purpose: Physical frailty is known to be closely associated with cognitive impairment and to be an early sign of Alzheimer's disease. We aimed to understand the characteristics of physical frailty and define factors associated with physical frailty in subjects with subjective cognitive decline (SCD) by analyzing amyloid data.

Methods: We prospectively enrolled subjects with SCD from a cohort study to identify predictors for the clinical progression to mild cognitive impairment or dementia from SCD (CoSCo).

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Developing reliable biomarkers is important for screening Alzheimer's disease (AD) and monitoring its progression. Although EEG is non-invasive direct measurement of brain neural activity and has potentials for various neurologic disorders, vulnerability to noise, difficulty in clinical interpretation and quantification of signal information have limited its clinical application. There have been many research about machine learning (ML) adoption with EEG, but the accuracy of detecting AD is not so high or not validated with Aβ PET scan.

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Introduction: This multicentre, randomised, open-label, and prospective study aimed to evaluate the effectiveness of memantine (memantine solution) on speech function in patients with moderate to severe Alzheimer's disease (AD) who were already on donepezil therapy.

Methods: Participants were divided into two groups: the drug trial group was administered donepezil + memantine (memantine solution), while the control group was administered only donepezil. Patients in the test group were required to increase the dose of memantine by 5 mg/day per week for the first 4 weeks and were maintained at 20 mg/day until the end of the trial.

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Background And Purpose: Subjective cognitive decline (SCD) indicates a self-perceived persistent cognitive worsening despite of normal performance in standard neuropsychological tests. Owing to its heterogeneity and potential risk of Alzheimer's disease, baseline biomarkers to predict cognitive decline are important. In the present study, we developed a home-based cognitive test (HCT) to monitor cognitive changes regularly without visiting hospitals.

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The Seoul Neuropsychological Screening Battery (SNSB) is known as a representative comprehensive neuropsychological evaluation tool in Korea since its first standardization in 2003. It was the main neuropsychological evaluation tool in the Clinical Research Center for Dementia of South Korea, a large-scale multi-center cohort study in Korea that was started in 2005. Since then, it has been widely used by dementia clinicians, and further solidified its status as a representative dementia evaluation tool in Korea.

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Background And Purpose: Early detection of subjective cognitive decline (SCD) due to Alzheimer's disease (AD) is important for clinical research and effective prevention and management. This study examined if quantitative electroencephalography (qEEG) could be used for early detection of AD in SCD.

Methods: Participants with SCD from 6 dementia clinics in Korea were enrolled.

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Background And Purpose: Subjective cognitive decline (SCD) refers to the self-perception of cognitive decline with normal performance on objective neuropsychological tests. SCD, which is the first help-seeking stage and the last stage before the clinical disease stage, can be considered to be the most appropriate time for prevention and treatment. This study aimed to compare characteristics between the amyloid positive and amyloid negative groups of SCD patients.

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Introduction: Subjective cognitive decline (SCD) is a self-reported cognitive decline without objective cognitive impairment. The relationship between audiometric hearing loss (HL) and cognitive function has not been reported in SCD. The purpose of this study was to investigate whether HL affects cognition-related indexes in SCD individuals.

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Background And Purpose: Oral administration of cholinesterase inhibitors is often associated with adverse gastrointestinal effects, and so developing an alternative administration route, such as transdermal, is urgently needed. The primary objective of this study was to determine the efficacy and safety of the IPI-301 donepezil transdermal patch compared with donepezil tablets (control) in mild-to-moderate probable Alzheimer's disease (AD).

Methods: This prospective, randomized, double-blind, double-dummy, two-arm parallel, multicenter trial included 399 patients, among whom 303 completed the trial.

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The presence of amyloid-β (Aβ) deposition is considered important in patients with amnestic mild cognitive impairment (aMCI), since they can progress to Alzheimer's disease dementia. Amyloid positron emission tomography (PET) has been used for detecting Aβ deposition, but its high cost is a significant barrier for clinical usage. Therefore, we aimed to develop a new predictive scale for amyloid PET positivity using easily accessible tools.

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A quantitative analysis of brain volume can assist in the diagnosis of Alzheimer's disease (AD) which is ususally accompanied by brain atrophy. With an automated analysis program Quick Brain Volumetry (QBraVo) developed for volumetric measurements, we measured regional volumes and ratios to evaluate their performance in discriminating AD dementia (ADD) and mild cognitive impairment (MCI) patients from normal controls (NC). Validation of QBraVo was based on intra-rater and inter-rater reliability with a manual measurement.

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We investigated the survival time of each clinical syndrome of frontotemporal dementia (FTD) and the impacts of behavioral and motor features on survival of FTD. A total of 216 patients with FTD [82 behavioral variant FTD (bvFTD), 78 semantic variant primary progressive aphasia (svPPA), 43 non-fluent/agrammatic variant PPA (nfvPPA), 13 FTD-motor neuron disease (MND)] were enrolled from 16 centers across Korea. Behaviors and parkinsonism were assessed using the Frontal Behavioral Inventory and Unified Parkinson's Disease Rating Scale Part III, respectively.

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Choline alphoscerate (α-GPC) is a choline-based compound and acetylcholine precursor commonly found in the brain; it has been known to be effective in treating neuronal injury and increasing the levels of acetylcholine (Ach) and brain-derived neurotrophic factor (BDNF) which in turn enhances memory and cognitive function. This study was designed to establish rat models of dual stress using noise and restraint in order to investigate the effect of α-GPC on cognitive function and neuronal differentiation after dual stress. The rats were randomly divided into four groups as follows: a control group (CG), a control with α-GPC group (CDG), a noise-restraint stress group (NRSG), and a noise-restraint stress with α-GPC group (NRSDG).

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Introduction: Subjective cognitive decline (SCD) can be considered as the preclinical manifestation of Alzheimer's disease (AD). The National Institute on Aging and the Alzheimer's Association criteria for preclinical AD proposed that subtle cognitive changes appear along with AD biomarkers in the late stage of preclinical AD. The objective of this study was to explore whether subtle cognitive impairment (SCI) in individuals with SCD is associated with brain amyloid-β (Aβ) status and SCD severity.

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Background: Preclinical studies in transgenic models of Alzheimer's disease (AD) suggest that DHP1401 has neuroprotective and memory-enhancing effects.

Objective: To evaluate the efficacy and safety of DHP1401 in AD patients treated with donepezilMethods:Methods: In a double-blind study, patients with mild-to-moderate AD were randomized (1:1:1) to receive a twice daily total dose of 500 mg or 1000 mg DHP1401 or placebo for 24 weeks. Tolerability and safety were monitored at baseline and weeks 12 and 24.

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The use of positron emission tomography (PET) as the initial or sole biomarker of β-amyloid (Aβ) brain pathology may inhibit Alzheimer's disease (AD) drug development and clinical use due to cost, access, and tolerability. We developed a qEEG-ML algorithm to predict Aβ pathology among subjective cognitive decline (SCD) and mild cognitive impairment (MCI) patients, and validated it using Aβ PET. We compared QEEG data between patients with MCI and those with SCD with and without PET-confirmed beta-amyloid plaque.

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Background: Subjective cognitive decline (SCD) is a self-perceived cognitive worsening without objective cognitive impairment. Due to its heterogeneity and potential risk of Alzheimer's disease (AD), baseline biomarkers to predict progression are clinically important. In the present study, cognitive trajectories during a 24-month period were compared between amyloid-positive SCD (A+SCD) and amyloid-negative SCD (A-SCD) subjects, and biomarkers associated with memory decline were investigated.

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