The Alzheimer disease 8 (AD8) is a brief informant-based measure that distinguishes individuals with very mild dementia and mild cognitive impairment from those with normal cognition. The aim of this study was to establish the validity, reliability, and discriminative properties of the Korean version of the AD8 (K-AD8). Evaluation was made on 155 patient-informant dyads. The K-AD8 scores with the Clinical Dementia Rating (CDR) and performance on neuropsychologic tests were compared. Internal consistency of the K-AD8 was significant (Cronbach alpha=0.88). The K-AD8 had strong correlation with CDR (Spearman rho=0.76). Concurrent validity was strong with the K-AD8 scores correlating with CDR domains and performance on neuropsychologic tests. The K-AD8 was found to have excellent test-retest reliability (weighted kappa=0.81) and good interrater reliability (intraclass correlation coefficient=0.89). The area under the receiver operator characteristic curve was 0.88, suggesting good discrimination between nondemented individuals and those with cognitive impairment. To distinguish CDR 0.5 from CDR 0, in particular, the K-AD8 (cutoff score of 2) had a sensitivity of 68% and a specificity of 90%. In conclusion, the K-AD8 is a sensitive screening tool in detecting very early dementia, indicating that the AD8 could work very well in a variety of cultural entities.

The LICA is a valid and reliable instrument for a diagnosis of dementia in both illiterate and literate elderly.

Background and Purpose: Evaluating instrumental activities of daily living (IADL) is an important part of procedure to diagnose dementia. The Korean-Instrumental Activities of Daily Living (K-IADL) has been used extensively in Korea. However, its cut-off score has not been reformulated since 2002. The purpose of this study was to yield a new optimal cut-off score for the K-IADL and confirm the validity of this new cut-off score with various dementia groups. Methods: We retrospectively collected a total of 2,347 patients' K-IADL data from 6 general hospitals in Korea. These patients had mild cognitive impairment (MCI) or dementia with various etiologies for cognitive impairment. We also recruited a normal control group (n=254) from the community. Korean-Mini Mental State Examination, Short version of the Geriatric Depression Scale, Clinical Dementia Rating, and Global Deterioration Scale were administered to all participants. Caregivers completed K-IADL and Barthel Index. Results: K-IADL scores were significantly different among dementia subgroups, but not significantly different among MCI subgroups. Based on internal consistency, correlations with other scales, and factor analysis, K-IADL showed excellent reliability and validity. The new optimal cut-off score to diagnose dementia was 0.40, which gave a sensitivity of 0.901 and a specificity of 0.916. Positive predictive value for dementia using the new cut-off score was 94.2% for Alzheimer's disease, 100% for vascular dementia, and 84% for Parkinson's disease. Conclusions: Our results illustrate that the new K-IADL cut-off score of 0.40 is reliable and valid for screening impairments of daily functioning resulting from various etiologies.

The SRT is a sensitive measurement of verbal memory function that can be used in clinical settings to discriminate between normal memory functioning and the very early and moderate stages of AD in a Korean population. Moreover, it is important to recognize that the SRT is more appropriate for subjects with a high level of education rather than a low level of education to differentiate normal cognitive aging from MCI or AD.

Prior research has shown that the total amount of white matter ischemia had no significant correlation with cognitive deficits. We compared the association of white matter hyperintensities (WMHs) of total as well as cholinergic pathways with clinical dementia severity and investigated whether cholinergic ischemic burden had an independent predictive value with respect to cognitive decline in subcortical vascular cognitive impairment (SVCI). Forty-eight patients underwent detailed neuropsychological tests and brain magnetic resonance imaging. Quantification of WMH in the total white matter and in cholinergic pathways was achieved using the visual Scheltens scale and Cholinergic Pathway HyperIntensity Scale (CHIPS), respectively. We explored the association between WMH scores and clinical dementia rating scale (CDR). To assess the relation between WMH and cognitive scores, multiple linear regression analysis was used. The CHIPS score was higher in subcortical vascular dementia compared to subcortical vascular MCI, while this difference was not found with the total TMHs (TWMH) score. The TWMH score had a positive correlation with CHIPS, however only CHIPS scores positively correlated with sum of box scores of CDR scale (CDR SB; ρ = .474, P = .001). Higher CHIPS scores were associated with lower performance on the semantic word fluency test (β = -.447, P = .036), whereas the TWMH scores had no independent predictive value with respect to cognitive impairment, after controlling for CHIPS score. Our data confirmed the association of ischemic damage within cholinergic pathways with dementia severity, independent of TWMH in SVCI. In addition, this cholinergic deficit is clinically relevant to cognitive deterioration, especially with frontal dysfunction.