Dataset Information

Reference Intervals for Plasma Amyloid ? in Korean Adults Without Cognitive Impairment.

ABSTRACT: Amyloid ? (A?) peptides are important components of plaques in patients with Alzheimer's disease (AD). Recent studies suggest that a low plasma ratio of A?42 to A?40 may precede the development of the sporadic form of AD. The aim of this study was to establish reference intervals for plasma A? in Korean adults. A total of 370 apparently healthy individuals (181 males and 189 females aged 40-69 yr) without cognitive impairment were enrolled. Plasma concentrations of A?40 and A?42 were measured by using a human amyloid ? assay kit (Immuno-Biological Laboratories, Japan). Reference intervals were established according to the "CLSI guidelines for defining, establishing, and verifying reference intervals in the clinical laboratory". There was no need to partition the data with respect to gender or age group. The 95th percentile reference intervals for A?40 and A?42 were 127-331 pg/mL and 2.31-19.84 pg/mL, respectively. The reference interval for the A?42/A?40 ratio was 0.011-0.092. Plasma A? concentrations obtained in this study could be used as reference intervals for clinical purposes.

SUBMITTER: Kim MY

PROVIDER: S-EPMC5011114 | biostudies-other | 2016 Nov

REPOSITORIES: biostudies-other

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Reference Intervals for Plasma Amyloid β in Korean Adults Without Cognitive Impairment.

Kim Min Young MY Kim Kyu Nam KN Cho Hye Min HM Lee Duck Joo DJ Cho Doo Yeoun DY

Annals of laboratory medicine 20161101 6

Amyloid β (Aβ) peptides are important components of plaques in patients with Alzheimer's disease (AD). Recent studies suggest that a low plasma ratio of Aβ42 to Aβ40 may precede the development of the sporadic form of AD. The aim of this study was to establish reference intervals for plasma Aβ in Korean adults. A total of 370 apparently healthy individuals (181 males and 189 females aged 40-69 yr) without cognitive impairment were enrolled. Plasma concentrations of Aβ40 and Aβ42 were measured by ...[more]

PMID: 27578514

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Project description:BackgroundCognitive impairment is associated with a negative prognosis in amyotrophic lateral sclerosis (ALS), as well as with clinical specificity. We investigate neuropsychological function in ALS patients without known genetic mutations in a Korean tertiary clinic.MethodsThree hundred and eighteen patients were enrolled in a prospective longitudinal cohort from September 2008 to February 2012. At the time of diagnosis of sporadic ALS, we carried out genetic and comprehensive neuropsychological tests on all patients, and collected demographic and clinical characteristics. Six cognitive domains, namely executive function, attention, language, calculation, visuospatial function and memory were evaluated. ANOVA and t-tests were used to assess differences in clinical characteristics and neuropsychological parameters between sporadic ALS patients. The Kaplan-Meier method and Cox proportional hazard model were used for survival analysis.ResultsOne hundred and sixty-six patients were categorized into five subtypes: normal cognition (ALS pure), cognitive impairment (ALSci), behavioral impairment (ALSbi), frontotemporal dementia (ALS-FTD), and other types of dementia. Seventy patients (70/166, 42.2%) were cognitively or behaviorally impaired. Among the impaired patients, eight (8/166, 4.8%) had FTD-type dementia and one (1/166, 0.6%) was Alzheimer's disease-type. The ALS patients with cognitive impairment (ALSci) and with FTD (ALS-FTD) were more severely impaired in executive function, attention, language and memory than the cognitively intact ALS patients (ALS pure). In a survival analysis, ALSci (β = 1.925, p = 0.025) and ALS-FTD groups (β = 4.150, p = 0.019) tended to have shorter survival than the ALS pure group.ConclusionsAbout half of ALS patients without known genetic variation have cognitive or behavioral impairment. ALS patients with cognitive abnormalities, especially FTD, have a poorer prognosis than those without cognitive impairment. In neuropsychological profiling, executive tasks were effective in identifying cognitive impairment in the ALS patients. It would be useful for clinicians to classify ALS according to neuropsychological profiles, and screen for subtle cognitive impairment.

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Dataset Information

Reference Intervals for Plasma Amyloid ? in Korean Adults Without Cognitive Impairment.

Publications

Reference Intervals for Plasma Amyloid β in Korean Adults Without Cognitive Impairment.

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