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Dive into the research topics where Hyun Jeong Han is active.

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Featured researches published by Hyun Jeong Han.


Current Medical Research and Opinion | 2011

Tolerability and efficacy of memantine add-on therapy to rivastigmine transdermal patches in mild to moderate Alzheimer's disease: a multicenter, randomized, open-label, parallel-group study

Seong Hye Choi; Kyung Won Park; Duk L. Na; Hyun Jeong Han; Eun-Joo Kim; Yong S. Shim; Jae-Hong Lee

Abstract Objective: To compare the tolerability and efficacy of combination therapy of memantine plus rivastigmine patch with rivastigmine patch monotherapy in patients with mild to moderate Alzheimers disease (AD). Research design and methods: In this multicenter, randomized, open-label study, patients entered an 8-week run-in period (a 5 cm2 rivastigmine patch for 4 weeks, then a 10 cm2 patch for 4 weeks) followed by 16 weeks of memantine plus rivastigmine patch or rivastigmine patch monotherapy. The primary outcome measure was the retention rate at the end of the trial. Clinical trial registration: clinicaltrials.gov. NCT01025466. Results: Overall, 88 and 84 patients received rivastigmine patch with and without memantine, respectively, and of these, 77 (87.5%) and 70 (83.3%) patients completed the study. The difference in retention rate was not significant (95% confidence interval: −6.3–14.7%). The incidence of adverse events (AEs) (53.4 vs. 50.6%) and discontinuation due to AEs (6.8 vs. 4.8%) were not different between patients with and without memantine. The most frequent AEs were skin irritation in patients with and without memantine (42.0 vs. 34.9%, p = 0.71), but discontinuation due to skin irritation was rare (4.5 vs. 2.4%, p = 0.74). The incidence of gastrointestinal AEs was very low in patients with and without memantine (nausea, 2.3 vs. 1.2%; vomiting, 1.1 vs. 1.2%). The Korean Version of the Cohen Mansfield Agitation Inventory scores favored rivastigmine patch monotherapy at the end of treatment (p = 0.01). Changes in other efficacy measures were similar between the groups. Conclusion: There were no significant differences in tolerability and safety between the treatment groups. The combination therapy of memantine plus rivastigmine patch did not show an advantage over rivastigmine patch monotherapy on efficacy analyses. The sample size for comparing tolerability may have been too small to detect a difference of efficacy between the two groups.


European Neurology | 2002

Hypometabolism and Interictal Spikes during Positron Emission Tomography Scanning in Temporal Lobe Epilepsy

Seung Bong Hong; Hyun Jeong Han; Suk-Young Roh; Dae Won Seo; Sang Eun Kim; Myoung-Hee Kim

To study the influence of interictal spikes on 18F-fluorodeoxyglucose positron emission tomography (FDG-PET), EEG monitoring was performed during PET scanning in 21 patients with temporal lobe epilepsy. Asymmetry indices were calculated in the polar, mesial, anterior-lateral, mid-lateral and posterior-lateral temporal region of interests of FDG-PET (PET-AI). 70.7% of spikes were recorded with their maximum at the anterior temporal region (F7, F8, FT9, FT10), 29.3% at mid-temporal (T7, T8), and none at posterior temporal region (P7, P8). Regardless of the side of epileptic focus, right-left difference of the total spikes had a significant negative correlation with right/left PET-AIs of the anterior-lateral temporal region (Spearman’s ρ = –0.565, p = 0.009), polar (ρ = –0.500, p = 0.021) and whole temporal region (ρ = –0.480, p = 0.028). FDG-PET hypometabolism may reflect not only a permanent functional deficit but also a transient regional cerebral dysfunction related to the occurrence of interictal spikes.


Journal of Clinical Neurology | 2011

Efficacy and Safety of Switching from Oral Cholinesterase Inhibitors to the Rivastigmine Transdermal Patch in Patients with Probable Alzheimer's Disease

Hyun Jeong Han; Jeong Ju Lee; Sun A. Park; Hyun-Young Park; Jeong Eun Kim; Young Soo Shim; Dong-Seok Shim; Eun-Joo Kim; Soo Jin Yoon; Seong Hye Choi

Background and Purpose The goal of this study was to estimate the efficacy and safety of the rivastigmine transdermal patch in patients with probable Alzheimers disease (AD) who cannot tolerate or do not respond to oral cholinesterase inhibitors (ChEIs). Methods A 24-week, prospective, open-label, single-arm, multicenter study was conducted from June 2009 to June 2010 in patients with probable AD. The enrolled patients had either a poor response or a decline in global function after treatment with oral ChEIs, or they were not able to tolerate treatment with oral ChEIs due to adverse events such as nausea or vomiting. A poor response was defined as a decrease of at least 2 points on the Korean version of the Mini-Mental State Examination (K-MMSE) within the previous 6 months (the decline in global function was determined by the investigator or caregiver). The efficacy of treatment was assessed using a follow-up Clinical Global Impression of Change (CGIC) assessment and K-MMSE conducted after 24 weeks, and safety was measured by the occurrence of adverse events and patient disposition. Results In total, 164 patients aged 74.7±7.52 years (mean±SD) and with 5.12±3.64 years of education were included. The study was completed by 70% of the patients (n=116), with 12.2% discontinuing due to adverse events. The most frequently reported adverse events (11%) were skin lesions, such as erythema or itching, followed by gastrointestinal problems (1.2%). Either an improvement or no decline in CGIC scores was reported for 82% of the patients. Conclusions The immediate switching of patients from an oral ChEI to the rivastigmine transdermal patch without a washout period was safe and well tolerated by the probable-AD patients in this study.


International Psychogeriatrics | 2015

Periventricular white matter hyperintensities and the risk of dementia: a CREDOS study.

Sangha Kim; Seong Hye Choi; Young-Min Lee; Min-Ji Kim; Young Don Kim; Jinyoung Kim; Jin Hong Park; Woojae Myung; Hae Ri Na; Hyun Jeong Han; Yong S. Shim; Jong Hun Kim; Soo Jin Yoon; Sang Yun Kim; Doh Kwan Kim

BACKGROUND Cerebral white matter hyperintensities (WMH) are prevalent incident findings on brain MRI scans among elderly people and have been consistently implicated in cognitive dysfunction. However, differential roles of WMH by region in cognitive function are still unclear. The aim of this study was to ascertain the differential role of regional WMH in predicting progression from mild cognitive impairment (MCI) to different subtypes of dementia. METHODS Participants were recruited from the Clinical Research Center for Dementia of South Korea (CREDOS) study. A total of 622 participants with MCI diagnoses at baseline and follow-up evaluations were included for the analysis. Initial MRI scans were rated for WMH on a visual rating scale developed for the CREDOS. Differential effects of regional WMH in predicting incident dementia were evaluated using the Cox proportional hazards model. RESULTS Of the 622 participants with MCI at baseline, 139 patients (22.3%) converted to all-cause dementia over a median of 14.3 (range 6.0-36.5) months. Severe periventricular WMH (PWMH) predicted incident all-cause dementia (Hazard ratio (HR) 2.22; 95% confidence interval (CI) 1.43-3.43) and Alzheimers disease (AD) (HR 1.86; 95% CI 1.12-3.07). Subcortical vascular dementia (SVD) was predicted by both PWMH (HR 16.14; 95% CI 1.97-132.06) and DWMH (HR 8.77; 95% CI 1.77-43.49) in more severe form (≥ 10 mm). CONCLUSIONS WMH differentially predict dementia by region and severity. Our findings suggest that PWMH may play an independent role in the pathogenesis of dementia, especially in AD.


Neurological Sciences | 2011

A case of rheumatoid meningitis: pathologic and magnetic resonance imaging findings

Hye Yun Kim; Jong Ho Park; Hwa Eun Oh; Hyun Jeong Han; Dong-Ick Shin; Man Ho Kim

Central nervous system (CNS) involvement is extremely rare in patients with rheumatoid arthritis (RA). Additionally, most patients with CNS involvement have chronic and severe RA. We present a report of a 66-year-old man who was diagnosed with rheumatoid meningitis and CNS vasculitis without a history of RA. His initial symptom was seizure. Brain magnetic resonance imaging showed leptomeningeal enhancement.CSF analysis revealed slight increase in the number of white blood cells. An examination of viral markers and culture studies for infectious etiology were unremarkable. However, the rheumatoid factor was positive and the levels of anti-cyclic citrullinated peptide antibody were very high. The patient was diagnosed with rheumatoid meningitis and received steroid therapy. However, he developed CNS vasculitis. We suggested that the possibility of rheumatoid meningitis should be considered during the differential diagnosis stage in patients with uncontrolled meningitis, even though RA does not typically show CNS involvement.


Dementia and Geriatric Cognitive Disorders | 2012

Neuropsychological Performance and Conversion to Alzheimer's Disease in Early- Compared to Late-Onset Amnestic Mild Cognitive Impairment: CREDOS Study

Byoung Seok Ye; Sang Won Seo; Yunhwan Lee; Seong Yoon Kim; Seong Hye Choi; Young Min Lee; Do Hoon Kim; Hyun Jeong Han; Duk L. Na; Eun-Joo Kim

Background: Amnestic mild cognitive impairment (aMCI) is regarded as a prodromal stage of Alzheimer’s disease (AD). Given that patients with early-onset AD (EOAD) and with late-onset AD (LOAD) are known to have different clinical courses, symptoms and neuroimaging findings, early-onset (EOMCI) and late-onset aMCI (LOMCI) might be expected to have similar differences as EOAD versus LOAD. Methods: Our study involving 425 patients with aMCI (124 EOMCI, 301 LOMCI), who were followed for around 1.5 years, and 958 normal control subjects (NC) investigated neuropsychological characteristics and prediction of progression to AD in patients with EOMCI versus LOMCI. Neuropsychological scores were compared between EOMCI, LOMCI and NC with analyses of covariance controlling age, gender, education and disease duration. The risk of AD conversion was evaluated by Cox proportional hazard analyses. Results: The baseline neuropsychological performances were comparable between EOMCI and LOMCI. Visuospatial memory for EOMCI and verbal memory scores for LOMCI were significant predictors of AD conversion. Conclusion: Our study indicates that EOMCI with visuospatial memory impairment, which implies underlying right predominant pathology, and LOMCI with poor verbal memory, which suggests underlying left predominant pathology, are individual conditions at an increased risk of conversion to AD.


Dementia and Geriatric Cognitive Disorders | 2012

Response to rivastigmine transdermal patch or memantine plus rivastigmine patch is affected by apolipoprotein E genotype in Alzheimer patients.

Hyun Jeong Han; Byeong C. Kim; Jun-Young Lee; Seungho Ryu; Hae Ri Na; Soo Jin Yoon; Hyun-Young Park; Joon Hyun Shin; Soo-Jin Cho; Hyon-Ah Yi; Mun Seong Choi; Jae-Hyeok Heo; Kyung Won Park; Kwang K. Kim; Seong Hye Choi

Background/Aims: The apolipoprotein E (APOE) genotype in response to pharmacological treatments in patients with Alzheimer’s disease (AD) remains a matter of controversy. This analysis investigated the effect of the APOE genotype on the clinical response to rivastigmine transdermal patch monotherapy or memantine plus rivastigmine patch in patients with mild to moderate AD. Methods: Two hundred and six (n = 206) patients with probable AD and Mini-Mental State Examination (MMSE) scores of 10–20 were randomized to rivastigmine patch monotherapy or memantine plus rivastigmine patch for 24 weeks. Of the 206 patients with probable AD, 146 patients who consented to genetic testing for APOE were included and assessed for this subgroup study. Results: There were no significant differences on MMSE, NPI, ADAS-cog, ADCS-ADL, CDR-SB, NPI and FAB between rivastigmine patch monotherapy and memantine plus rivastigmine patch according to the APOE genotype. However, patients with moderately severe AD (MMSE ≤15) who were APOE ε4 carriers showed higher responder rates on ADCS-ADL with memantine plus rivastigmine patch compared to rivastigmine patch monotherapy. Conclusion: Moderately severe AD patients with the APOE ε4 allele may respond more favorably to memantine plus rivastigmine patch than ε4 noncarriers.


Journal of Alzheimer's Disease | 2015

Elevation of the Plasma Aβ40/Aβ42 Ratio as a Diagnostic Marker of Sporadic Early-Onset Alzheimer's Disease.

Hyeong Jun Kim; Kyung Won Park; Tae Eun Kim; Ji Young Im; Ho Sik Shin; Saeromi Kim; Dong Hyun Lee; Byoung Seok Ye; Jong Hun Kim; Eun-Joo Kim; Kee Hyung Park; Hyun Jeong Han; Jee Hyang Jeong; Seong Hye Choi; Sun Ah Park

BACKGROUND Although plasma amyloid-β (Aβ) levels have been evaluated as a possible diagnostic marker of Alzheimers disease (AD), the findings are inconsistent. OBJECTIVE The present study aimed to validate plasma levels of Aβ40, Aβ42, and the Aβ40/Aβ42 ratio as biomarkers of AD in subjects with early-onset AD (EOAD) without familial AD genetic mutations. METHODS Patients with sporadic EOAD (sEOAD) were prospectively recruited by nine neurology clinics. Plasma levels of Aβ40 and Aβ42 were measured using a sandwich enzyme-linked immunosorbent assay (ELISA) in 100 sEOAD (50-69 year-old) and 46 age-matched normal control subjects (50-72 year-old). Cerebrospinal fluid (CSF) was obtained from 32 sEOAD subjects and 25 controls. The integrity of the blood-brain barrier was assessed using the CSF/plasma albumin ratio. RESULTS The plasma levels of Aβ42 were significantly lower, while the Aβ40/Aβ42 ratio was significantly higher in sEOAD patients than in controls. The levels of Aβ40, Aβ42, and the Aβ40/Aβ42 ratio did not differ in relation to the APOEɛ4 allele. The CSF/plasma albumin ratio was comparable between the two groups, and the plasma parameters of Aβ proteins were not significantly associated. A multivariate analysis revealed that an increased Aβ40/Aβ42 ratio is valuable for the discrimination of sEOAD from controls (β=0.344, p=0.000). The area under the ROC curve for the Aβ40/Aβ42 ratio was 0.76, and a cut-off ratio of 5.87 was suggested to have 70% sensitivity and 68% specificity. CONCLUSION The plasma Aβ40/Aβ42 ratio had moderate validity for the discrimination of sEOAD patients from age-matched controls.


Neurological Sciences | 2010

Magnetic resonance imaging of pachymeningeal enhancement in Vogt-Koyanagi-Harada disease

Hyun Jeong Han; Hye Yun Kim; Jong-Ho Park; Eun Ja Lee; Do Gyun Kim; Dong-Ick Shin

Vogt-Koyanagi-Harada (VKH) disease is a systemic disease consisting of bilateral granulomatous panuveitis combined with cutaneous and neurologic manifestations. However, there have been few reports of brain magnetic resonance imaging (MRI) in VKH disease. A 54-year-old Korean woman presented with severe periorbital pain, blurred vision and meningismus. Ophthalmologic examination disclosed bilateral optic disc edema with peripapillary nerve fiber hemorrhages. Lumbar puncture revealed monocytic pleocytosis. After a diagnosis of VKH disease was made, the patient was treated with high-dose corticosteroid. Brain MRI showed diffusely thickened posterior ocular walls with retinal detachment and perineural infiltrative changes along the optic nerves and adjacent pachymeningeal enhancement of the anterior temporal lobes bilaterally. We report a case of VKH disease with panuveitis and meningeal involvement of the anterior temporal lobe detected by brain MRI.


Journal of Korean Medical Science | 2010

Reversible Splenium Lesion of the Corpus Callosum in Hemorrhagic Fever with Renal Failure Syndrome

Shin-Hye Baek; Dong-Ick Shin; Hyung-Suk Lee; Sung-Hyun Lee; Hye-Young Kim; Kyeong Seob Shin; Seung Young Lee; Ho-Seong Han; Hyun Jeong Han; Sang-Soo Lee

This is the first case of virus-associated encephalitis/encephalopathy in which the pathogen was Hantaan virus. A 53-yr-old man presented fever, renal failure and a hemorrhagic tendency and he was diagnosed with hemorrhagic fever with renal failure syndrome (HFRS). In the course of his illness, mild neurologic symptoms such as dizziness and confusion developed and magnetic resonance images revealed a reversible lesion in the splenium of the corpus callosum. This case suggests that HFRS patients with neurologic symptoms like dizziness and mental slowing should be considered to have structural brain lesions and to require brain imaging studies.

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Eun-Joo Kim

Pusan National University

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Duk L. Na

Samsung Medical Center

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Jong-Ho Park

Seoul National University

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