Dong Y. Lee

A normative study of the CERAD neuropsychological assessment battery in the Korean elderly

This study aimed to explore the effects of age, education and gender on the performance of eight tests in the Korean version of the CERAD neuropsychological assessment battery and to provide normative information on the tests in the Korean elderly. The battery was administered to 618 healthy volunteers aged from 60 to 90. People with serious neurological, medical and psychiatric disorders, including dementia, were excluded. Multiple linear regression analyses were performed to assess the relative contribution of the demographic factors on the score of each cognitive test. Age, education, and gender were found to have significant effects on the performance of many tests in the battery. Based on these results, 4 overlapping age normative tables (60 to 74, 65 to 79, 70 to 84, and 75 to 90 years of age) with 3 educational strata (0 to 3 years, 4 to 6 years, and 7 years and more) for both genders are presented. The normative information will be useful for a clinical interpretation of the CERAD neuropsychological battery in Korean elderly as well as for comparing the performance of the battery across countries.

Diagnostic Accuracy of Mini-Mental Status Examination and Revised Hasegawa Dementia Scale for Alzheimer’s Disease

To compare the diagnostic accuracies of the Revised Hasegawa Dementia Scale (HDS-R) and Mini-Mental Status Examination (MMSE) for Alzheimer’s diseases (AD), we administered them simultaneously to 82 AD patients and 82 age- and sex-matched nondemented control subjects. The area under the receiver operator curve (AUC) for AD of the HDS-R (AUCHDS-R) and MMSE (AUCMMSE) were bigger than 0.90 indicating that both tests are useful for detecting AD. However, AUCHDS-R (0.952) was significantly larger than that of the AUCMMSE (0.902) regardless of the educational level of the subjects, indicating that the HDS-R is more accurate than MMSE in diagnosing AD. Moreover, the superiority of the HDS-R (AUCHDS-R = 0.894) to the MMSE (AUCMMSE = 0.704) remained significant in mild AD patients alone, who are the focus of screening. In conclusion, the HDS-R is better than the MMSE as a screening instrument for AD.

A telemedicine system as a care modality for dementia patients in Korea.

Because dementia is a chronic debilitating disease, there are the issues of the difficulty in continuous long-term care and limited accessibility to medical service. We developed the telemedicine system for dementia patients and aimed to examine the acceptance, reliability, and clinical outcome of our telemedicine service. We established the Dementia Telemedicine Center in connection with two recipient sites in 1996. The reliability of the center, which provides telemedicine, tele-education, and telecounseling services, was tested by comparing assessment via our system with in-person assessment, and the clinical outcome was assessed by rating the changes of behavioral symptoms. There have been 140 registered patients for 2 years. The general acceptance of our system by the patients and caregivers was good, and the consistency rates between the assessment via our telemedicine system and in-person assessment ranged from 76% to 89%. A considerable proportion of dementia patients in nursing homes (46%) showed relative clinical improvements through our service. Our telemedicine system seems to be reliable and effective for the assessment and care of dementia patients. Our future direction is to promote our system as a core model of the home-based care system for dementia patients.

Depression in Vascular Dementia Is Quantitatively and Qualitatively Different from Depression in Alzheimer's Disease

Background/Aims: To compare the prevalence and characteristics of depression in vascular dementia (VaD) and Alzheimer’s disease (AD) after adjusting for dementia severity and gender. Methods: One hundred and eight pairs of VaD and AD patients matched for dementia severity and gender were assessed. Results: Major depressive disorder (MDD) was more prevalent in the VaD group than in the AD group (20.4% in VaD, 10.2% in AD, p = 0.04, Cochran-Mantel-Haenszel, CMH, test) regardless of the dementia severity and gender. The odds ratio for developing MDD in the VaD group versus the AD group was estimated to be 2.20 (95% confidence interval = 1.02–4.74). Neurovegetative symptoms such as ‘felt tired and weak all the time’ (30.6% in VaD, 13.9% in AD, p = 0.003, CMH test) and ‘changed weight without trying’ (16.7% in VaD, 6.5% in AD, p = 0.02, CMH test) were more prevalent in the VaD group than in the AD group. Conclusion: Depression in VaD was quantitatively and qualitatively different from that in AD regardless of the severity of dementia and gender; depression was more prevalent, severer and more retarded and vegetative in VaD than in AD.

The Domain-Specific, Stage-Limited Impact of the Apolipoprotein E Epsilon-4 Allele on Cognitive Functions in Alzheimer’s Disease

To examine the impact of the APOE Ε4 allele on the cognitive functions of Alzheimer’s disease (AD) patients, we administered the eight neuropsychological tests from the Consortium to Establish a Registry for Alzheimer’s Disease Neuropsychological Assessment Battery to 118 Korean AD patients. The impact of the APOE Ε4 allele was significant in the Word List Recall Test (WLRT) and the Word List Recognition Test (WLRcT) only, and its impact was confined to the very mild AD (VMAD) patients (F = 7.65, d.f. = 2, p < 0.01 for WLRT; F = 3.27, d.f. = 2, p = 0.04 for WLRcT). In the VMAD group, the performance on the two tests of the APOE-Ε4-positive patients was poorer than that of the APOE-Ε4-negative patients. Our findings suggest that the impact of the APOE Ε4 allele on cognitive functions in AD may be domain specific and confined to the early stage of AD.

A Normative Study of the Revised Hasegawa Dementia Scale: Comparison of Demographic Influences between the Revised Hasegawa Dementia Scale and the Mini-Mental Status Examination

Background/Aims: We investigated the demographic influence on the performance of the Revised Hasegawa Dementia Scale (HDS-R) and provided normative data of the HDS-R in the elderly. Methods: The HDS-R was administered to 803 community-dwelling cognitively normal elderly subjects aged 55 years or over. Cognitive disorders and psychiatric disorders were strictly excluded using the CERAD-K assessment packet and the Mini-International Neuropsychiatric Interview. The demographic influence on the performance of the HDS-R was examined using multiple linear regression analyses, and compared with that on the performance of the Mini-Mental Status Examination (MMSE) using the Chow test and t statistics. Overlapping strata were used in developing age-, education- and gender-specific normative data of the HDS-R. Results: Age, education, and gender influenced significantly the performance of the HDS-R, and explained 22.5% of the total score variance. Older age, lower education, and male gender were associated with lower performance of the HDS-R. However, the demographic influence on the HDS-R was much weaker than that on the MMSE (t = 5.578, d.f. = 800, p < 0.001). The normative data of the HDS-R stratified by age (60–69, 70–79, ≧80), education (0–6, 7–12, ≧13), and gender were presented. Conclusions: The HDS-R was more robust to demographic influences than the MMSE, and normative data may contribute to improving further its diagnostic accuracy for dementia.

The Severe Cognitive Impairment Rating Scale – An Instrument for the Assessment of Cognition in Moderate to Severe Dementia Patients

Background/Aims: This study aimed to develop a brief, reliable and valid test for cognitive function of severely demented patients. Methods: We constructed the Severe Cognitive Impairment Rating Scale, which consisted of 11 items covering memory, language, visuospatial function, frontal function and orientation, and investigated its reliability and validity on 267 subjects [normal: 65, very mild Alzheimer’s disease (AD): 42, mild AD: 58, moderate AD: 36, severe AD: 44, profound AD: 22]. Results: The internal consistency obtained by Cronbach’s coefficient α was 0.93. The interrater reliability and test-retest reliability in the moderately to severely impaired subjects with an MMSE score of ≤14 was 0.99 (p < 0.001) and 0.90 (p < 0.001), respectively. It showed significant correlation with Severe MMSE (r = 0.96, p < 0.01), MMSE (r = 0.86, p < 0.01) and Clinical Dementia Rating (r = –0.83, p < 0.01). It was robust to both the floor effect in the severe/profound stage of AD and the ceiling effect in the mild/moderate stage of AD. Exploratory factor analysis yielded 2 factors (automatic informational processing and controlled informational processing) accounting for 73.5% of the total variance. Conclusions: The Severe Cognitive Impairment Rating Scaleis a valid and reliable test for evaluating the cognitive function of advanced AD patients.

Beta-Amyloid Associated Differential Effects of APOE ε4 on Brain Metabolism in Cognitively Normal Elderly

OBJECTIVEnAlthough apolipoprotein (APOE) ε4 allele is a well-established risk factor for late-onset Alzheimer disease (AD), the mechanism of its effects on AD pathogenesis is not fully understood. We aimed to investigate the effects of APOE genotype on regional cerebral glucose metabolism in cognitively normal (CN) elderly. We further tried to elucidate whether or not such effects are associated with beta-amyloid protein (Aβ) deposition.nnnMETHODSn31 CN elderly participants underwent clinical examination, a range of neuropsychological tests, APOE genotyping, and Pittsburgh compound-B- and fluorodeoxyglucose-PET scans.nnnRESULTSn17 APOE ε4 carriers and 15 non-carriers were included. Both hypometabolic and hypermetabolic regions were observed in ε4 carriers compared with noncarriers when age, education, and sex were controlled. When the degree of global cerebral Aβ deposition was adjusted, the hypometabolic regions in the temporo-parietal area (i.e., BA 22 and 39) largely disappeared, whereas the hypermetabolic regions persisted in medial frontal and anterior temporal areas (i.e., BA 38, 11, and 39). Behaviorally, verbal episodic memory scores of APOE ε4 carriers were slightly lower than those of noncarriers, though still within normal range.nnnCONCLUSIONSnOur findings indicate that decreased cerebral glucose metabolism in the temporoparietal junction associated with APOE ε4 in CN elderly appears to be mediated by Aβ deposition, and the effect of APOE ε4 on hypermetabolism in the frontal and anterior temporal regions is independent of Aβ and may be associated with presence of compensatory mechanism in CN elderly with the ε4 allele.

Neither the butyrylcholinesterase K variant nor transferrin C2 variant confers a risk for Alzheimer's disease in Koreans.

Summary. To investigate the possible involvement of the butyrylcholinesterase (BCHE) K variant and transferrin (TF) C2 variant in the manifestation of Alzheimers disease (AD), we analyzed the BCHE, TF and apolipoprotein E (APOE) genotypes of 164 sporadic AD patients and 239 normal elderly controls.The frequencies of the BCHE K and TF C2 did not differ between the AD patients and controls (P > 0.1). The occurrence of the APOE ε4 did not influence the distribution of the BCHE K and TF C2 variants (P > 0.1). No linkage disequilibrium between the BCHE K and TF C2 was observed either in both the AD patients and controls (P > 0.1).In conclusion, neither the BCHE K nor the TF C2 confers a risk for AD.

No association between presenilin 1 (PS1) intronic polymorphism and sporadic Alzheimer's disease in Koreans

Summary. To investigate the possible involvement of an intronic polymorphism in the presenilin 1 (PS1) gene and its interactions with the aplolipoprotein E (APOE) or alpha-1 antichymotrypsin (ACT) polymorphisms in the manifestation of AD, we analyzed the PS1, APOE and ACT genotypes of 100 sporadic AD patients and 199 normal elderly controls in Koreans. The genotypic (χ2 = 0.92, df = 2, P > 0.1) and allelic (χ2 = 0.01, df = 1, P > 0.1) frequencies of the PS1 polymorphism in the late- and early-onset sporadic AD patients did not differ from those in the controls. And the occurrence of the APOE ε4 allele and ACT A allele did not influence the distribution of the PS1 intronic polymorphism. The PS1 intronic polymorphism didnt influence the age-at-onset of AD (F = 0.02, df = 2, P > 0.1). In conclusion, the PS1 intronic polymorphism did not modify the risk for sporadic AD, neither independently nor synergistically with the APOE ε4 allele or ACT A allele, in Koreans.