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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]

Background and purpose: Subcortical vascular cognitive impairment (SVCI) is characterized by the presence of cerebral small vessel disease (CSVD) markers. Some SVCI patients also show Alzheimer's disease and cerebral amyloid angiopathy markers. However, the effects of these imaging markers on long‐term clinical outcomes have not yet been established. The present study, therefore, aimed to determine how these imaging markers influence functional disability and/or mortality. Methods: We recruited 194 participants with SVCI from the memory clinic and followed them up. All participants underwent brain magnetic resonance imaging at baseline, and 177 (91.2%) participants underwent beta‐amyloid (Aβ) positron emission tomography. We examined the occurrence of ischemic or hemorrhagic strokes. We also evaluated functional disability and mortality using the modified Rankin scale. To determine the effects of imaging markers on functional disability or mortality, we used Fine and Gray competing regression or Cox regression analysis. Results: During a 8.6‐year follow‐up period, 46 of 194 patients (23.7%) experienced a stroke, 110 patients (56.7%) developed functional disabilities and 75 (38.6%) died. Aβ positivity (subdistribution hazard ratio [SHR] = 2.73), greater white matter hyperintensity (WMH) volume (SHR = 3.11) and ≥3 microbleeds (SHR = 2.29) at baseline were independent predictors of functional disability regardless of the occurrence of stroke. Greater WMH volume (hazard ratio = 2.07) was an independent predictor of mortality. Conclusions: Our findings suggest that diverse imaging markers may predict long‐term functional disability and mortality in patients with SVCI, which in turn may provide clinicians with a more insightful understanding of the long‐term outcomes of SVCI. [ABSTRACT FROM AUTHOR]

Background: Amyloid‐β (Aβ) accumulation, a major biomarker in Alzheimer's disease (AD), induces tau accumulation, eventually resulting in cognitive decline. However, Aβ trajectory in cognitively normal participants has not been extensively investigated, yet. Modeling of Aβ trajectory remains an important goal, as future treatments targeting Aβ are expected to be developed. In the present study, we therefore investigated whether they might be divided into the normal aging group and the pathological group with increased amyloid. We also compared the differences between the non‐accumulating group and accumulating group. Method: We included 297 subjects from the Alzheimer's Disease Neuroimaging Initiative database, who showed normal cognition at baseline. All subjects underwent neuropsychological test, apolipoprotein E (APOE) genotype test, brain MRI, and an average of 3.03 follow‐up 18F‐florbetapir (AV45) PET scans. The original dataset was divided by 6:4 to create a training set and a validation set. Latent Class Growth Analysis was used for statistical analysis. Result: Based on the information criterion, the model consisting of three classes was found to be the best with a high entropy of 0.979: class 1 (non‐accumulating group; n = 117, 65.7%), class 2 (accumulating group; n = 46, 25.8%), and class 3 (high accumulation group; n = 15, 8.4%) (Figure). The accumulating group had more APOE ε4 carriers and a higher tau burden than the non‐accumulating group (Table). Conclusion: Our study showed that there is the heterogeneity of Aβ trajectories according to aging in the normal cognitive elderly. Heterogeneity of Aβ accumulation and early detection of accumulating group may be helpful in early diagnosis and treatment of AD. [ABSTRACT FROM AUTHOR]

Objective: Diagnosis of reversible cerebral vasoconstriction syndrome (RCVS) is currently based on luminographic findings of vasoconstriction. In addition to vasoconstriction, the blood-brain barrier (BBB) breakdown has been postulated as a central mechanism of RCVS. Our aim was to document BBB breakdown in patients with RCVS and its role for the pathophysiology-based diagnosis of RCVS.Methods: We prospectively recruited 72 consecutive patients with thunderclap headache who did not have aneurysmal subarachnoid hemorrhage from April 2015 to July 2016 at the Samsung Medical Center. Based on the International Classification of Headache Disorders-3 beta criteria and neuroimaging, patients were classified as having RCVS (n = 41; "definite" in 29 imaging-proven patients and "probable" in 12 imaging-negative patients), other secondary causes (n = 7), and thunderclap headache of undetermined cause (n = 24). BBB breakdown was evaluated using contrast-enhanced fluid-attenuated inversion recovery magnetic resonance imaging.Results: BBB breakdown was documented in 20 (69.0%) patients with definite RCVS, 3 (25.0%) patients with probable RCVS, and none with other secondary causes. BBB breakdown was present in RCVS patients with (n = 4) and without (n = 19) concomitant posterior reversible encephalopathy syndrome. In patients with RCVS, the extent of BBB breakdown was independently associated with neurological complications (multivariate odds ratio = 1.48 per 1 territorial increase, 95% confidence interval = 1.04-2.12, adjusted p = 0.032). Three (12.5%) patients with thunderclap headache of undetermined cause were newly classified as having RCVS by the presence of BBB breakdown.Interpretation: This is the first study to show BBB breakdown in patients with RCVS. This finding might broaden our understanding of the pathophysiology and clinical spectrum of RCVS. Ann Neurol 2017;81:454-466. [ABSTRACT FROM AUTHOR]

Objectives/hypothesis: Chronic suppurative otitis media (CSOM) is a common infectious condition that can cause hearing loss and persistent otorrhea. The prevalence rates of CSOM in developed countries is typically <1%, whereas developing countries and some racial groups have shown higher prevalence rates exceeding 4%. The aim of this study was to investigate the prevalence of CSOM in South Korea and associated factors using data from the Korea National Health and Nutrition Examination Survey during 2009-2012.Study Design: Cross-sectional analysis of a nationwide health survey.Methods: Physical examination, interview, and laboratory testing were performed by the field survey team including an otolaryngologist.Results: Among the population >4 years of age (n = 25,147), the prevalence of CSOM was 3.13% (95% confidence interval [CI] = 3.07-3.92). Specifically, the prevalence of tympanic membrane perforation, retraction pocket, and obvious cholesteatoma was 1.78% (95% CI = 1.51-2.00), 1.21% (95% CI = 1.02-1.40), and 0.34% (95% CI = 0.24-0.44), respectively. The prevalence of CSOM increased with age (P < .001) and had a female predominance (P = .014). In a multivariate analysis of associated factors in 14,396 participants >19 years of age, hearing threshold, the presence of tinnitus, diabetes, drinking alcohol, residence in a row house, and education level of the mother were significantly associated with CSOM (P < .05).Conclusions: The prevalence of CSOM in the Korean population >4 years of age was 3.13%. Understanding of epidemiologic data and associated factors might contribute to the better management of CSOM and reducing the social burden.Level Of Evidence: 4. Laryngoscope, 126:2351-2357, 2016. [ABSTRACT FROM AUTHOR]

Objective: Depression is prevalent among elders with cognitive impairment. Cerebral white matter hyperintensities (WMH) have consistently been implicated in late-life depression and in cognitive impairment. This study aims to clarify the factors related to prevalence, persistence, and new onset of depressive symptoms in subjects with mild cognitive impairment (MCI).Methods: As part of a multicenter prospective study, the Clinical Research Center for Dementia of South Korea (CREDOS) Study, we enrolled 590 subjects diagnosed with MCI and with no prior history of depression. Depressive symptoms were assessed by the Korean version of the Geriatric Depression Scale short form (SGDS-K) at baseline and at follow-up visits. Brain magnetic resonance imaging was performed at baseline to quantify WMH using a visual rating scale.Results: The baseline prevalence of clinically significant depressive symptoms (SGDS-K ≥5) was 51.4%, and this feature was associated with younger age, lower educational achievement, and higher Clinical Dementia Rating Sum of Boxes (CDR-SB) scores. Persistence of depressive symptoms across the study period was significantly associated with baseline CDR-SB and depression scores. New onset of depression (SGDS-K ≥8; incidence 15.7%) among subjects free of depressive symptoms (SGDS-K <5) at baseline was associated with severe deep subcortical, but not periventricular, WMH.Conclusions: In patients with MCI aged 50 years or older, depressive symptoms were highly prevalent. Cognitive status was closely related to both prevalence and persistence of depressive symptoms, while new onset of depression was associated with deep subcortical WMH severity in this MCI cohort. Our findings provide prospective evidence consistent with the vascular depression hypothesis. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Purpose To determine a new cutoff value that can further distinguish between the incomplete and complete discoid lateral meniscus (DLM). Materials and Methods Twenty-one cases of incomplete DLM and 42 cases of complete DLM without tear were included. In all, 105 patients with normal lateral menisci were included as a control group. We measured the ratio of the shortest width of the lateral meniscus to the longest width of the tibia (ratio 1) and the ratio of the shortest width of the medial meniscus to the shortest width of the lateral meniscus (ratio 2). Results By applying a cutoff value of ratio 1 as 0.32 between two incomplete and complete DLM groups, the proportion of the complete and incomplete DLM diagnosed cases among the true cases were 84% and 94%, respectively. By applying a cutoff value of ratio 2 as 0.40 between two incomplete and complete DLM groups, the proportion of the complete and incomplete DLM diagnosed cases among the true cases were 84% and 75%, respectively. Conclusion A cutoff value of 0.32 using the ratio of the shortest width of the lateral meniscus and the longest width of the tibia are probably useful to help distinguish between complete DLM and incomplete DLM. Additionally, the new ratio using the width of the medial meniscus is also useful to improve distinguishing between the types of DLM. J. Magn. Reson. Imaging 2013;38:417-421. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Aims The objective of this study was to derive a customised birth weight standard curve in our institute and to compare the perinatal outcomes of small-for-gestational-age ( SGA) births classified by population-based versus customised birth weight standards. Methods We surveyed 9052 normal singleton deliveries and generated customised standards by adjusting for maternal characteristics and neonatal gender. We compared adverse perinatal outcomes between SGA and non- SGA births classified by both standards. Results According to the population-based standards, mothers of SGA infants were younger, thinner and shorter and had higher rates of nulliparity and female births. We adjusted for these maternal characteristics and neonatal gender in our customised standards. Multivariate analysis revealed that there were no differences in neonatal composite morbidity between the standards. However, infants classified as SGA by the customised standards showed a significantly higher rate of neonatal intensive care unit ( NICU) admission than those classified by the population-based standards. Conclusion Our study showed that customised SGA made no significant differences in neonatal composite morbidity, only a modest increase in NICU admission rate compared to population-based standard. To clarify the association of adverse perinatal outcomes with customised SGA, larger studies are required. [ABSTRACT FROM AUTHOR]

Background: Aging and the apolipoprotein E e4 (APOE4) are the two major risk factors for Alzheimer's disease (AD). Previous reports suggest that the impact of APOE4 on increasing risk for AD differs according to age. However, whether the impact of APOE4 on cognitive trajectories in AD differ according to age is not well established. Thus, we evaluated the impact of APOE4 on cognitive trajectories in early‐onset AD (EOAD) and late‐onset AD (LOAD). Method: In this retrospective longitudinal study, we collected 807 AD patients who underwent two or more neuropsychological tests after they were diagnosed with AD. We categorized the patients into two groups according to their age at symptom onset: 222 patients with EOAD (age at onset <65 years) and 585 patients with LOAD (age at onset ≥ 65 years). Linear mixed‐effects model analyses were performed to evaluate the effects of APOE4 on cognitive changes after controlling for age, sex, and education in each group. Result: In LOAD, APOE4 carriers showed more rapid cognitive decline compared to APOE4 noncarriers in language and visuospatial functions. However, in EOAD, APOE4 noncarriers showed more rapid cognitive decline compared to APOE4 carriers in general cognitive function and in all cognitive domains including language, visuospatial, memory, and frontal executive function. Conclusion: Our data showed that APOE4 is associated with accelerated cognitive decline in LOAD whereas the association is reversed in EOAD. We suggest that in EOAD, there might be other genetic or environmental factors that overshadow the detrimental effects of APOE4. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented which is concerned with the article "Comparison of Perinatal Outcomes in Small-for-Gestational-Age Infants Classified by Population-Based Versus Customised Birth Weight Standards" by Hyun-Hwa Cha et al.