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BACKGROUND: Vocal acoustic features are potential biomarkers of elderly depression. Previous automated diagnostic tests for depression have employed unstandardized speech samples, and few studies have considered differences in voice reactivity. We aimed to develop a voice-based screening test for depression measuring vocal acoustic features of elderly Koreans while they read a series of mood-inducing sentences (MIS). METHODS: In this case-control study, we recruited 61 individuals with major depressive disorder and 143 healthy controls (mean age [SD]: 72 [6]; female, 70%) from the community-dwelling elderly population. Participants were asked to read MIS and their variation pattern of acoustic features represented by the correlation distance between two MIS were analyzed as input features using the univariate feature selection technique and subsequently classified by AdaBoost. RESULTS: Acoustic features showing significant discriminatory performances were spectral and energy-related features for males (sensitivity 0.95, specificity 0.88, and accuracy 0.86) and prosody-related features for females (sensitivity 0.73, specificity 0.86, and accuracy 0.77). The correlation distance between negative and positive MIS was significantly shorter in the depressed group than in the healthy control (F = 18.574, P < 0.001). LIMITATIONS: Small sample size and relatively homogenous clinical profile of depression could limit the generalizability. CONCLUSIONS: While reading MIS, spectral and energy-related acoustic features for males and prosody-related features for females are good discriminators for major depressive disorder. These features may be used as biomarkers of depression in the elderly.
Subject(s)
Depressive Disorder, Major , Acoustics , Aged , Case-Control Studies , Depressive Disorder, Major/diagnosis , Female , Humans , Male , Speech , Speech AcousticsABSTRACT
OBJECTIVE: This study estimated the incidence of driving-related adverse events and examined the association of cognitive function with the risk of future driving-related adverse events in the elderly Korean male population. METHODS: We analyzed 1,172 male drivers aged 60 years or older in the Korean Longitudinal Study on Cognitive Aging and Dementia (KLOSCAD). Using the data from Korean National Police Agency, we classified the participants into three groups: safe driving (drove for 2 years after baseline without a traffic accident or repeated violations), driving cessation (stopped driving), and risky driving (one or more traffic accidents or repeated violations). We estimated the incidences of driving cessation and risky driving, and examined the effect of cognitive function on their risks. RESULTS: The incidence of driving cessation and risky driving in the Korean male drivers aged 60 years or older was 19.3 and 69.9 per 1,000 person-years respectively and increased in the late 80s. Drivers with better baseline Word List Memory Test scores showed less risky driving (OR=0.94, p=0.039). CONCLUSION: Driving-related adverse events increased in late 80s, and better memory function was protective against these events.
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OBJECTIVE: Cardiovascular diseases are representative risk factors for the onset of cognitive decline. The purpose of this study was to confirm the relationship between diastolic blood pressure and cognitive function in elderly people in Korea. METHODS: Data from subjects who were enrolled in the prospective Korean Longitudinal Study on Cognitive Aging and Dementia were used in this study. Data from 701 subjects whose diastolic blood pressure range did not change (≤79 mm Hg or ≥80 mm Hg) over 2 years were analyzed. To analyze the differences in cognitive function between the groups at the 2-year follow-up, an analysis of covariance was performed with covariates, which were significantly different between the two groups, and the baseline cognitive function. RESULTS: Significant differences were observed between the two groups, and the mean scores on the constructional praxis (η2=0.010) and word list recall tests (η2=0.018) in the diastolic blood pressure ≥80 mm Hg group were higher than those in the diastolic blood pressure ≤79 mm Hg group at the 2-year follow-up. CONCLUSION: These results indicate that maintaining a DBP below 79 mm Hg presents a greater risk of cognitive decline in Korean elderly people.
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OBJECTIVE: This study aimed to examine the association between normal-but-low folate levels and cognitive function in the elderly population using a prospective cohort study. METHODS: We analyzed 3,910 participants whose serum folate levels were within the normal reference range (1.5-16.9 ng/mL) at baseline evaluation in the population-based prospective cohort study named the "Korean Longitudinal Study on Cognitive Aging and Dementia." The association between baseline folate quartile categories and baseline cognitive disorders [mild cognitive impairment (MCI) or dementia] was examined using binary logistic regression analysis adjusting for confounding variables. The risks of incident MCI and dementia associated with the decline of serum folate level during a 4-year follow-up period were examined using multinomial logistic regression analysis. RESULTS: The lowest quartile group of serum folate (≥1.5, ≤5.9 ng/mL) showed a higher risk of cognitive disorders than did the highest quartile group at baseline evaluation (odds ratio 1.314, p=0.012). Over the 4 years of follow-up, the risk of incident dementia was 2.364 times higher among subjects whose serum folate levels declined from the 2nd-4th quartile group to the 1st quartile than among those for whom it did not (p=0.031). CONCLUSION: Normal-but-low serum folate levels were associated with the risk of cognitive disorders in the elderly population, and a decline to normal-but-low serum folate levels was associated with incident dementia. Maintaining serum folate concentration above 5.9 ng/mL may be beneficial for cognitive status.
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OBJECTIVE: Due to an unprecedented rate of population aging, South Korea is facing a dementia epidemic. For this reason, the Korean Longitudinal Study on Cognitive Aging and Dementia (KLOSCAD) was launched in 2009 with support from the Korean Health Industry Development Institute to investigate the epidemiology, biopsychosocial risk factors, and outcomes of dementia and dementia-related conditions. METHODS: The KLOSCAD is the first nationwide multi-center population-based prospective cohort study. In October 2010, 12,694 individuals were randomly sampled from residents aged 60 years or older who lived in 13 districts across South Korea. In the baseline assessment, which was conducted from November 2010 through October 2012, 6,818 (53.7%) individuals participated. Follow-up assessments have been conducted every two years, with the first follow-up assessment conducted between November 2012 and October 2014, and the second between November 2014 and October 2016. The third is now in progress, and will span from November 2016 to October 2018. Diagnosis of cognitive disorders, neuropsychological battery, behavioral and psychological symptoms of dementia, activities of daily living, physical and neurologic examination and laboratory tests, life styles, quality of life, and identification of death were evaluated in each assessment. RESULTS: The cumulative drop-out rate at the second follow-up assessment was 38.7%. Dementia and mild cognitive impairment were 5.0% and 27.0%, respectively. CONCLUSION: The KLOSCAD may provide strong scientific evidence for advancing the fight against dementia both in Korea and globally.
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BACKGROUND: The aim of this study was to investigate the association of gait speed and gait variability, an index of how much gait parameters, such as step time, fluctuate step-to-step, with risk of cognitive decline in cognitively normal elderly individuals. While high gait variability is emerging as an early indicator of dementing illnesses, there is little research on whether high gait variability predicts cognitive decline in cognitively normal elderly who have no evidence of cognitive impairment. METHODS: In this 4-year prospective cohort study on 91 community-dwelling cognitively normal elderly individuals without cerebral ischemic burden or Parkinsonism, we evaluated gait speed and step time variability using a tri-axial accelerometer placed on the center of body mass, and diagnosed mild cognitive impairment (MCI) according to the International Working Group on MCI. We performed Kaplan-Meier analysis with consecutive log-rank testing for MCI-free survival by cohort-specific tertiles of gait speed; hazard ratios (HR) of incident MCI were estimated using Cox proportional hazards regression analysis adjusted for age, sex, education level, Cumulative Illness Rating Scale score, GDS score, and presence of the apolipoprotein E ε4 allele. RESULTS: Out of the 91 participants in the baseline assessment, 87 completed one or more 2-year follow-up assessments, and the median duration of follow-up was 47.1 months. Kaplan-Meier curves of incident MCI show evident differences in risk by gait variability group (χ2 = 9.64, p = 0.002, log-rank test). Mean MCI-free survival in the high variability group was 12% shorter than in the mid-to-low tertile group (47.4 ± 1.74 [SD] vs. 54.04 ± 0.52 months), while it was comparable between gait speed groups (51.59 ± 0.70 vs. 50.64 ± 1.77 months; χ2 = 1.16, p = 0.281). In multivariate analysis, subjects with high gait variability showed about 12-fold higher risk of MCI (HR = 11.97, 95% CI = 1.29-111.37) than those with mid-to-low variability. However, those with slow gait speed showed comparable MCI risk to those with mid-to-high speed (HR = 5.04, 95% CI = 0.53-48.18). CONCLUSIONS: Gait variability may be a better predictor of cognitive decline than gait speed in cognitively normal elderly individuals without cerebral ischemic burden or Parkinsonism.
Subject(s)
Aging , Cognitive Dysfunction , Gait , Aged , Aged, 80 and over , Aging/pathology , Aging/psychology , Alleles , Apolipoprotein E4/genetics , Female , Humans , Male , Middle Aged , Multivariate Analysis , Proportional Hazards Models , Prospective Studies , Risk FactorsABSTRACT
BACKGROUND: We investigated the effects of lifetime cumulative ginseng intake on cognitive function in a community-dwelling population-based prospective cohort of Korean elders. METHODS: Community-dwelling elders (N = 6422; mean age = 70.2 ± 6.9 years, education = 8.0 ± 5.3 years, female = 56.8%) from the Korean Longitudinal Study on Cognitive Aging and Dementia were included. Among them, 3918 participants (61.0%) completed the 2-year and 4-year follow-up evaluations. Subjects were categorized according to cumulative ginseng intake at baseline evaluation; no use group, low use (< 5 years) group, and high use (≥ 5 years) group. One-way analysis of covariance (ANCOVA) was conducted to compare the impact of cumulative ginseng intake on baseline Consortium to Establish a Registry for Alzheimer's Disease Assessment Packet neuropsychological battery total score (CERAD total score) and Mini-Mental State Examination (MMSE) score among the three groups while adjusting for potential covariates. A repeated-measures ANCOVA was performed to investigate the impacts on the changes in CERAD total scores and MMSE scores during the 4 years of follow-up. RESULTS: The high use group showed higher CERAD total scores compared to the no use group after controlling for age, sex, education years, socioeconomic status, smoking, alcohol intake, presence of hypertension, stroke history, Geriatric Depression Scale, Cumulative Illness Rating Scale, and presence of the APOE e4 allele (F(2, 4762) = 3.978, p = 0.019). The changes of CERAD total score for 2 or 4 years of follow-up did not differ according to the use of ginseng. CONCLUSIONS: Cumulative ginseng use for longer than 5 years may be beneficial to cognitive function in late life.
Subject(s)
Cognition/physiology , Cognitive Aging , Life Style , Panax/metabolism , Aged , Aged, 80 and over , Analysis of Variance , Cohort Studies , Female , Geriatric Assessment , Humans , Independent Living , Logistic Models , Male , Neuropsychological Tests , PsychometricsABSTRACT
OBJECTIVE: To investigate sleep disturbances that induce cognitive changes over 4 years in nondemented elderlies. METHODS: Data were acquired from a nationwide, population-based, prospective cohort of Korean elderlies (2,238 normal cognition [NC] and 655 mild cognitive impairment [MCI]). At baseline and 4-year follow-up assessments, sleep-related parameters (midsleep time, sleep duration, sleep latency, subjective sleep quality, sleep efficiency, and daytime dysfunction) and cognitive status were measured using the Pittsburgh Sleep Quality Index and Consortium to Establish a Registry for Alzheimer's Disease Assessment, respectively. We used logistic regression models adjusted for covariates including age, sex, education, apolipoprotein E genotype, Geriatric Depression Scale, Cumulative Illness Rating Scale, and physical activity. RESULTS: In participants with NC, long sleep latency (>30 minutes), long sleep duration (≥7.95 hours), and late midsleep time (after 3:00 am) at baseline were related to the risk of cognitive decline at 4-year follow-up assessment; odds ratio (OR) was 1.40 for long sleep latency, 1.67 for long sleep duration, and 0.61 for late midsleep time. These relationships remained significant when these variables maintained their status throughout the follow-up period. Newly developed long sleep latency also doubled the risk of cognitive decline. In those with MCI, however, only long sleep latency reduced the chance of reversion to NC (OR = 0.69). INTERPRETATION: As early markers of cognitive decline, long sleep latency can be used for elderlies with NC or MCI, whereas long sleep duration and relatively early sleep time might be used for cognitively normal elderlies only. Ann Neurol 2018;83:472-482.
Subject(s)
Aging/physiology , Cognitive Dysfunction/diagnosis , Cognitive Dysfunction/physiopathology , Sleep/physiology , Aged , Aged, 80 and over , Aging/pathology , Cognitive Dysfunction/epidemiology , Cohort Studies , Female , Follow-Up Studies , Humans , Longitudinal Studies , Male , Prospective Studies , Random Allocation , Republic of Korea/epidemiologyABSTRACT
BACKGROUND: Spaced retrieval training (SRT) is a nonpharmacological intervention for mild cognitive impairment (MCI) and dementia that trains the learning and retention of target information by recalling it over increasingly long intervals. We recently developed the Ubiquitous Spaced Retrieval-based Memory Advancement and Rehabilitation Training (USMART) program as a convenient, self-administered tablet-based SRT program. We also demonstrated the utility of USMART for improving memory in individuals with MCI through an open-label uncontrolled trial. METHODS: This study had an open-label, single-blind, randomized, controlled, two-period crossover design. Fifty patients with MCI were randomized into USMART-usual care and usual care-USMART treatment sequences. USMART was completed or usual care was provided biweekly over a 4-week treatment period with a 2-week washout period between treatment periods. Primary outcome measures included the Word List Memory Test, Word List Recall Test (WLRT), and Word List Recognition Test. Outcomes were measured at baseline, week 5, and week 11 by raters who were blinded to intervention type. An intention-to-treat analysis and linear mixed modeling were used. RESULTS: Of 50 randomized participants, 41 completed the study (18% dropout rate). The USMART group had larger improvements in WLRT score (effect size = 0.49, p = 0.031) than the usual care group. There were no significant differences in other primary or secondary measures between the USMART and usual care groups. Moreover, no USMART-related adverse events were reported. CONCLUSIONS: The 4-week USMART modestly improved information retrieval in older people with MCI, and was well accepted with minimal technical support. TRIAL REGISTRATION: ClinicalTrials.gov NCT01688128 . Registered 12 September 2012.
Subject(s)
Cognitive Behavioral Therapy/methods , Cognitive Dysfunction/diagnosis , Cognitive Dysfunction/therapy , Neurological Rehabilitation/methods , Aged , Cross-Over Studies , Female , Humans , Male , Neuropsychological Tests , Pregnancy , Treatment OutcomeABSTRACT
We developed and evaluated the effect of Multimodal Cognitive Enhancement Therapy (MCET) consisting of cognitive training, cognitive stimulations, reality orientation, physical therapy, reminiscence therapy, and music therapy in combination in older people with mild cognitive impairment (MCI) or mild dementia. This study was a multi-center, double-blind, randomized, placebo-controlled, two-period cross-over study (two 8-week treatment phases separated by a 4-week wash-out period). Sixty-four participants with MCI or dementia whose Clinical Dementia Rating was 0.5 or 1 were randomized to the MCET group or the mock-therapy (placebo) group. Outcomes were measured at baseline, week 9, and week 21. Fifty-five patients completed the study. Mini-Mental State Examination (effect sizeâ=â0.47, pâ=â0.013) and Alzheimer's Disease Assessment Scale-Cognitive Subscale (effect sizeâ=â0.35, pâ=â0.045) scores were significantly improved in the MCET compared with mock-therapy group. Revised Memory and Behavior Problems Checklist frequency (effect sizeâ=â0.38, pâ=â0.046) and self-rated Quality of Life - Alzheimer's Disease (effect sizeâ=â0.39, pâ=â0.047) scores were significantly improved in the MCET compared with mock-therapy. MCET improved cognition, behavior, and quality of life in people with MCI or mild dementia more effectively than conventional cognitive enhancing activities did.
Subject(s)
Cognitive Behavioral Therapy/methods , Cognitive Dysfunction/rehabilitation , Dementia/rehabilitation , Aged , Aged, 80 and over , Cross-Over Studies , Double-Blind Method , Female , Follow-Up Studies , Humans , Male , Outcome Assessment, Health Care , Psychiatric Status Rating Scales , Time FactorsABSTRACT
Despite its significance as a contributing factor for late-life dementia risk, illiteracy is frequently underappreciated in the management of dementia. In this study, we estimated the proportion of dementia cases attributable to illiteracy using the population attributable fraction (PAF), and calculated to what extent the monetary cost of dementia could be saved in the future by reducing illiteracy from the South Korean, Latin American, South Asian/Middle Eastern, and African populations. We collected necessary data from the 2011 United Nations Human Development Report and prevalence studies conducted in these regions. Additional variables not included in the above sources were estimated using a logit model under a "trend scenario"-based assumption. Around 16% of the total number of dementia cases in South Korea in 2015 can be attributed to illiteracy, with this figure predicted to decline to around 2% by 2050. This translates to a saving in dementia care costs of approximately 52 billion USD, providing we are successful in theoretically eradicating illiteracy as of 2015, in the population aged 65 years or under. Likewise, reducing illiteracy to 50% in Latin America, South Asia/The Middle East, and Africa by 2050 could generate further cost savings of between 71 and 244 billion, 13 and 94 billion, and 17 and 78 billion USD, respectively. Even public policies aimed solely at reducing illiteracy in the childhood, adolescent, or middle-aged population could potentially have a role in the primary prevention of dementia. Moving forward, governments will need to address this issue in a purposeful and systematic manner.