Jung-Min Pyun

Abstract Background The combinatorial effect of multiple genetic factors calculated as a polygenic risk score (PRS) has been studied to predict disease progression to Alzheimer’s disease (AD) from mild cognitive impairment (MCI). Previous studies have investigated the performance of PRS in the prediction of disease progression to AD by including and excluding single nucleotide polymorphisms within the region surrounding the APOE gene. These studies may have missed the APOE genotype-specific pred

PURPOSE: Among other emerging amyloid-targeting blood-based biomarkers, Multimer Detection System-Oligomeric Amyloid-β (MDS-OAβ) measures dynamic changes in concentration of oligomeric amyloid-β (OAβ), which is considered the main pathogenic culprit of Alzheimer's disease (AD), in plasma after spiking with synthetic amyloid-β (Aβ). We aimed to investigate the predictability of MDS-OAβ on amyloid positron emission tomography (PET) positivity. PATIENTS AND METHODS: A total of 96 subjects who visit

BACKGROUND: Although thyroid dysfunction has been considered as a cause of reversible cognitive impairment, association between subclinical hypothyroidism and cognitive impairment is controversial. OBJECTIVE: We compared cognitive profiles of patients in an euthyroid or subclinical hypothyroid (sHypo) state, as well as their disease progression from mild cognitive impairment (MCI) to dementia within 3 years. METHODS: We included 2,181 patients in a euthyroid and 284 in a sHypo state over 60 year

BACKGROUND: Fibrinogen is considered a marker of vascular pathology, indicating a weakened blood-brain barrier, and has a causative role in neuroinflammation and neurodegeneration. Little is known about the relationship between fibrinogen levels and cognitive function in patients with mild cognitive impairment (MCI). We aimed to investigate differences in cognitive profiles according to plasma fibrinogen levels in patients with MCI and the influence of plasma fibrinogen levels on cognitive decli

BACKGROUND: Cholinesterase inhibitors (ChEIs) are an FDA-approved symptomatic treatment for patients with Alzheimer's disease (AD). Its efficacy in patients with mild cognitive impairment (MCI), however, is controversial. Nonetheless, ChEIs have often been used in patients with MCI. From the perspective that ChEIs were developed based on the pathomechanism of AD, the effect of ChEIs in MCI patients could be different depending on the amyloid burden. In this retrospective observational study, we

Although driving by adults with cognitive impairment is an important public health concern, little is known about the indicators of driving cessation in patients with mild cognitive impairment (MCI). We aimed to investigate the prevalence of driving cessation in patients with MCI and the predictive value of cognitive performances for driving cessation. Patients with MCI were recruited in the Seoul National University Bundang Hospital; they met following inclusion criteria. Age range of 51⁻80 yea

BACKGROUND: Sundown syndrome (SS) in patients with Alzheimer's disease (AD) is characterized by aggravation of behavioral problems at sunset. Disturbance of the circadian rhythm, a possible cause of SS, also facilitates amyloidopathy and reduces sleep quality. However, the associations of SS with amyloidopathy and sleep quality remain unclear. OBJECTIVE: To investigate the prevalence of SS in patients with AD, the association between SS and APOEɛ4 carrier, representing an enhanced amyloid pathol

Amyloid-β (Aβ) is a key protein in Alzheimer's disease (AD) in that its accumulation induces complex pathological changes. Although there has been extensive research on the metabolism of Aβ in AD, new compelling results have recently emerged. Historically, the production and clearance of Aβ have been thought to originate in the central nervous system (CNS). However, recent evidence suggests that the production and clearance of Aβ can also occur in the peripheral system, and that the peripherally

INTRODUCTION: Our previously developed blood-based transcriptional risk scores (TRS) showed associations with diagnosis and neuroimaging biomarkers for Alzheimer's disease (AD). Here, we developed brain-based TRS. METHODS: We integrated AD genome-wide association study summary and expression quantitative trait locus data to prioritize target genes using Mendelian randomization. We calculated TRS using brain transcriptome data of two independent cohorts (N = 878) and performed association analysi

Abstract Introduction We investigated single‐nucleotide polymorphisms (SNPs) in IFITM3 , an innate immunity gene and modulator of amyloid beta in Alzheimer's disease (AD), for association with cognition and AD biomarkers. Methods We used data from the Alzheimer's Disease Neuroimaging Initiative (ADNI; N = 1565) and AddNeuroMed ( N = 633) as discovery and replication samples, respectively. We performed gene‐based association analysis of SNPs in IFITM3 with cognitive performance and SNP‐based asso

Introduction: There has been significant development in blood-based biomarkers targeting amyloidopathy of Alzheimer's disease (AD). However, the guidelines for integrating such biomarkers into AD diagnosis are still inadequate. Multimer Detection System-Oligomeric Amyloid-β (MDS-OAβ) as a plasma biomarker detecting oligomerization tendency is available in the clinical practice. Main text: We suggest how to interpret the results of plasma biomarker for amyloidopathy using MDS-OAβ with neuropsycho

Late-onset progressive cerebellar ataxia is a diagnostic challenge because of a poor correlation between genotype and phenotype, and a broad range of secondary causes that extend beyond the neurological field. We report the case of a 45-year-old woman admitted after 2 years of slowly progressing cerebellar ataxia, dysarthria, and emotional instability. Notably, she was diagnosed with diabetes insipidus at the age of 35. As 'idiopathic cerebellar ataxia' was suspected, diagnostic tests, including

Various plasma biomarkers for amyloid-β (Aβ) have shown high predictability of amyloid PET positivity. However, the characteristics of discordance between amyloid PET and plasma Aβ42/40 positivity are poorly understood. Thorough interpretation of discordant cases is vital as Aβ plasma biomarker is imminent to integrate into clinical guidelines. We aimed to determine the characteristics of discordant groups between amyloid PET and plasma Aβ42/40 positivity, and inter-assays variability depending

Abstract Background Cholinesterase inhibitors (ChEIs) are prescribed for Alzheimer’s disease (AD) and sometimes for mild cognitive impairment (MCI) without knowing underlying pathologies and its effect on cognition. We investigated the frequency of ChEI prescriptions in amyloid-negative MCI and their association with cognitive changes in the Alzheimer’s Disease Neuroimaging Initiative (ADNI) cohort. Methods We included participants with amyloid positron emission tomography (PET)-negative MCI fro