Screening Ability of Subjective Memory Complaints, Informant-Reports for Cognitive Decline, and Their Combination in Memory Clinic Setting

OBJECTIVE: This study aimed to compare the accuracy of subjective memory complaints, informant-reports for cognitive declines, and their combination for screening cognitive disorders in memory clinic setting. METHODS: One-hundred thirtytwo cognitively normal (CN), 136 mild cognitive impairment (MCI), and 546 dementia who visited the memory clinic in the Seoul National University Hospital underwent standardized clinical evaluation and comprehensive neuropsychological assessment. The Subjective Memory Complaints Questionnaire (SMCQ) and the Seoul Informant Report Questionnaire for Dementia (SIRQD) were used to assess subjective memory complaints and informant-reports for cognitive declines, respectively. RESULTS: Both SMCQ and SIRQD showed significant screening ability for MCI, dementia, and overall cognitive disorder (CDall: MCI plus dementia) (screening accuracy: 60.1–94.6%). The combination of SMCQ and SIRQD (SMCQ+SIRQD) was found to have significantly better screening accuracy compared to SMCQ alone for any cognitive disorders. SMCQ+SIRQD also significantly improved screening accuracy of SIRQD alone for MCI and CDall, but not for dementia. CONCLUSION: Our findings suggest that the combined information of both subjective memory complaints and informant-reports for cognitive declines can improve MCI screening by each individual information, while such combination appears not better than informant-reports in regard of dementia screening.

Korean Brain Aging Study for the Early Diagnosis and Prediction of Alzheimer's Disease: Methodology and Baseline Sample Characteristics

OBJECTIVE: The Korean Brain Aging Study for the Early Diagnosis and Prediction of Alzheimer's disease (KBASE) aimed to recruit 650 individuals, aged from 20 to 90 years, to search for new biomarkers of Alzheimer's disease (AD) and to investigate how multi-faceted lifetime experiences and bodily changes contribute to the brain changes or brain pathologies related to the AD process. METHODS: All participants received comprehensive clinical and neuropsychological evaluations, multi-modal brain imaging, including magnetic resonance imaging, magnetic resonance angiography, [11C]Pittsburgh compound B-positron emission tomography (PET), and [18F]fluorodeoxyglucose-PET, blood and genetic marker analyses at baseline, and a subset of participants underwent actigraph monitoring and completed a sleep diary. Participants are to be followed annually with clinical and neuropsychological assessments, and biannually with the full KBASE assessment, including neuroimaging and laboratory tests. RESULTS: As of March 2017, in total, 758 individuals had volunteered for this study. Among them, in total, 591 participants–291 cognitively normal (CN) old-aged individuals, 74 CN young- and middle-aged individuals, 139 individuals with mild cognitive impairment (MCI), and 87 individuals with AD dementia (ADD)–were enrolled at baseline, after excluding 162 individuals. A subset of participants (n=275) underwent actigraph monitoring. CONCLUSION: The KBASE cohort is a prospective, longitudinal cohort study that recruited participants with a wide age range and a wide distribution of cognitive status (CN, MCI, and ADD) and it has several strengths in its design and methodologies. Details of the recruitment, study methodology, and baseline sample characteristics are described in this paper.

Distinct Clinical Characteristics Depending on Cerebral Amyloid Positivity in Patients with Alzheimer Disease Dementia

OBJECTIVE: The present study investigated the clinical characteristics of Alzheimer's disease (AD) dementia with low brain amyloid-beta (Aβ-AD) burden comparing with AD dementia with high amyloid-beta burden (Aβ+AD). We also developed a prediction model for the amyloid positivity on ¹¹C-labelled Pittsburgh Compound B (PiB) positron emission tomography (PET) with distinct clinical variables in AD dementia patients. METHODS: Fifty-nine clinically defined AD dementia individuals, who participated in the Korean Brain Aging Study for Early diagnosis and prediction of AD (KBASE) study, were included. All the subjects received comprehensive clinical evaluations and PiB-PET. Based on cerebral PiB retention, all subjects were divided into Aβ+AD (n=47) and Aβ-AD (n=12) subgroups. To develop a prediction model for amyloid positivity, stepwise multiple logistic regression analysis was conducted. RESULTS: When compared to Aβ+AD, Aβ-AD showed older age, later age-at-onset, and lower education. In regard of risk factors for dementia, Aβ-AD had higher frequency of hypertension and diabetes mellitus as well as lower frequency of apolipoprotein E (APOE) ε4 allele. Although there was no between group difference in Clinical Dementia Rating (CDR) or CDR sum-of-boxes scores, mini-mental state examination and constructional recall scores were higher for Aβ-AD than Aβ+AD. The final amyloid positivity prediction model included APOE4 genotype, hypertension, and diabetes mellitus. CONCLUSION: The findings from this study indicated that clinically diagnosed AD dementia may have high possibility of not being pathological AD if they have older age and higher vascular risks, and did not have APOE4 genotype.

Prevalence and Associated Factors of Depression in Mild Cognitive Impairment

OBJECTIVE: The aims of this study were to investigate the prevalence of co-morbid depression and related factors of depression in mild cognitive impairment (MCI) patients. METHODS: Nine hundred and six MCI individuals were included in this study. Depression was defined as major and minor depressive disorder according to the Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV). Depression-related demographic and clinical factors were also explored through multivariate logistic regression analysis. RESULTS: In MCI patients, the prevalence of depression as defined according to the DSM-IV diagnostic criteria was 1.8% for major depressive disorder, 11.4% for minor depressive disorder, and overall 13.2% for both. Multivariate logistic regression showed that increased prevalence of overall depression was associated with female gender and non-amnestic subtype of MCI. CONCLUSION: Our findings based on a large number of MCI subjects who visited memory clinic indicated that more than ten percent of MCI patients have comorbid depression. In addition, female and non-amnestic subtype of MCI patients seems to be more vulnerable to depression.