Hippocampus Mediates the Effect of Emotional Support on Cognitive Function in Older Adults.

BACKGROUND: Despite strong evidence that emotional support has a protective effect on cognitive decline, the neural basis for how an individual's emotional support is associated with cognition is unknown. We investigated if the hippocampus mediates the relationship between emotional support and cognition in older adults. METHOD: Four hundred and ten nondemented Korean older adults were classified into two groups according to their Medical Outcomes Study-Social Support Survey emotional support scores: the poor emotional support (score ≤ 25th percentile of entire sample) and normal emotional support (score > 25th percentile of entire sample) groups. Cognitive function was assessed using the Verbal Memory Score and Consortium to Establish a Registry for Alzheimer's Disease Assessment Packet Neuropsychological Assessment Battery total score (CERAD-TS). Left and right hippocampal volume were obtained using 3T T1-weighted magnetic resonance images. Mediation analyses were conducted. RESULTS: In the association of emotional support with Verbal Memory Score, left hippocampal volume played a mediating role (indirect effect = 0.40, SE = 0.21, bias-corrected 95% confidence interval = 0.04, 0.86). In the association of emotional support with CERAD-TS, both left (indirect effect = 0.82, SE = 0.45, bias-corrected 95% confidence interval = 0.09, 1.83) and right (indirect effect = 0.51, SE = 0.32, bias-corrected 95% confidence interval = 0.02, 1.24) HPVs played mediating roles. CONCLUSIONS: The hippocampus may mediate the association between emotional support and cognition. Higher levels of emotional support may be associated with better verbal memory and global cognition via larger HPV.

Depressive symptoms and suicidal behaviours in adolescent non-daily smokers compared to daily smokers and never-smokers in Korea: National cross-sectional study.

INTRODUCTION: We aimed to investigate the association of non-daily smoking with depressive symptoms and suicidal behaviours among adolescents by analysing data from the 2016 Korean Youth Risk Behavior Web-based Survey (KYRBWS), a national school-based survey. METHODS: We analysed data from a nationally representative sample of Korean adolescents aged 12-18 years (n = 65,528). We investigated the risks of depressive symptoms, suicide ideation, plan and attempt in adolescent non-daily smokers using multiple logistic regression analyses after adjusting for confounding factors. Taking into account the trajectory of smoking patterns in adolescents, we assessed all analyses with stratification by early (aged 12-15) and late (aged 16-18) adolescents. RESULTS: Among early adolescents, non-daily smokers were more likely to have depressive symptoms, suicide ideation and plan compared with never smokers and even more likely to have depressive symptoms compared with daily smokers. Among late adolescents, non-daily smokers had higher risks of depressive symptoms, suicide ideation, plan and attempt than never smokers, whereas the risk for suicide attempts was lower than daily smokers. CONCLUSIONS: Our findings suggest that non-daily smoking in adolescents was associated with risks for depressive symptoms and suicidal behaviours, and the association was more prominent in early adolescents. Careful attention on the mental health of adolescent non-daily smokers is needed because this is an increasing and easily overlooked group.

Impact of Mild Cognitive Impairment on Mortality and Cause of Death in the Elderly.

BACKGROUND: Mild cognitive impairment (MCI) is a cognitive state that lies on the continuum between normal aging and dementia, and the prevalence of MCI is higher than dementia. However, the risk for mortality of people with MCI has been far less studied than that of people with dementia, and the population attributable risk percent (PAR%) of death attributable to MCI has not been estimated yet. OBJECTIVE: To investigate the impact of MCI on mortality and the cause of death in the elderly, and to estimate the PAR% of deaths attributable to MCI. METHODS: Data came from 7,315 elderly subjects aged ≥60 years without dementia from two cohort studies with diagnostic assessments of MCI at baseline. Deaths among participants were confirmed through the nationwide mortality database of Statistics Korea. RESULTS: MCI increased the risk of mortality in a multivariate Cox proportional model adjusting for age, sex, education, smoking, alcohol drinking, chronic illness, depression, vascular components, and cohort (hazard ratio = 1.59, 95% confidence interval 1.30, 1.94). PAR% of death attributable to MCI was 10.7% for age 65-74 years, 16.0% for age 75-84 years, and 24.2% for age ≥85 years. In the elderly with MCI, mortality risks from cerebrovascular disease, respiratory disease, and external causes were higher than in the cognitively normal elderly. CONCLUSIONS: Our results suggest that the mortality risk of MCI in Asian countries may be comparable to that in Western countries, and MCI can contribute to the death of the elderly as much as dementia.

Effects of lifetime cumulative ginseng intake on cognitive function in late life.

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.

Exposure to pesticide as a risk factor for depression: A population-based longitudinal study in Korea.

BACKGROUND: Exposure to pesticides is associated with mental disorders, including depression, especially among occupationally exposed populations, such as farmers. The results of experimental studies ascribed the negative effects of pesticides on mental health to their neurotoxic and endocrine-disrupting activities. PURPOSE: This study aimed to investigate the association between the risk of depression and high- or low-level exposure to pesticides in a rural population. METHODS: This longitudinal study was performed in 2005-2008 (baseline) and 2008-2012 (follow-up) to evaluate the risk of depression among 2151 Korean adults. A standardized questionnaire was used to obtain information on depression upon self-reported exposure to pesticide based on the Center for Epidemiologic Studies Depression Scale. Logistic regression analysis was performed to evaluate the association between pesticide exposure and depression. We adjusted the data for age, cigarette smoking status, current alcohol use, monthly income, educational level, marriage status, and religion. RESULTS: Among the individuals who reported depression, the number of participants who used pesticides was significantly higher than that who did not (N=61 [7.2%] vs. N=54 [4.2%], P=0.003). A positive association was noted between >20-year period of pesticide use and depression (odds ratio [OR], 2.35; 95% confidence interval [CI], 1.41-3.88). Individuals who reported depression showed greater odds of being exposed to higher pesticide concentrations (OR, 2.33; 95% CI, 1.40-3.88) and experiencing pesticide poisoning (OR, 5.83; 95% CI, 1.80-18.86) than those who did not. CONCLUSION: Exposure to pesticides at a high concentration was found to be associated with depressive symptoms among Korean adults.

Cost-effectiveness of nationwide opportunistic screening program for dementia in South Korea.

Although more demand for screening for dementia is envisaged, the cost-effectiveness of opportunistic population screening for dementia at a nationwide level has never been directly investigated. Since 2010, Korea has implemented "the National Dementia Early Detection Program" (NDEDP) for the aged. This study aims to investigate the cost-effectiveness of the NDEDP of Korea and to explore the requirements for enhancing its cost-effectiveness. A Markov model was developed to simulate the disease progression of dementia patients. Data sources for the model parameters included the NDEDP database for cohort characteristics and other national representative data. The model's estimates of the expected costs and Quality Adjusted Life Years (QALYs) for each strategy were used to calculate the incremental cost-effectiveness ratio of screening compared to no screening, and sensitivity analysis was performed to assess the effect of key variables on the cost-effectiveness. Screening showed that the cost per QALY gained ranged from $24,150 to $35,661 depending on the age group. The probability of screening being cost-effective was highest in the group over 75 years old in a wide range of willingness to pay (WTP). The implementation of an opportunistic screening program for dementia can be cost-effective depending on disease severity, treatment effect, costs by disease stage, ages of the participants, and the societal WTP. Above all things, improving access to more effective therapies in slowing the course of the disease is essential since the main benefit of earlier diagnosis for dementia is starting early treatment and subsequent savings. Although it is too early to conclude the cost-effectiveness of opportunistic population screening for dementia, this current study may be a meaningful step toward generating practical evidence for implementing an effective and efficient dementia screening program.

A new scoring method of the mini-mental status examination to screen for dementia.

BACKGROUND: Although the Mini-Mental Status Examination (MMSE) is the most widely used screening instrument for dementia, it has several limitations. METHODS: We developed and validated a new scoring method of the MMSE, namely the short form of the MMSE (MMSE-S). RESULTS: The MMSE-S was more robust to demographic influences than the MMSE. The influence of education, in particular, was smaller in the MMSE-S compared to the MMSE (p < 0.01). The diagnostic accuracy of the MMSE-S for very mild to mild dementia was also better than that of the original MMSE (p < 0.0001). Its specificity, in particular, was higher than that of the original MMSE. In Korea, we could improve the post-test probability for dementia from 46.88 to 64.76% by employing the MMSE-S instead of the MMSE. We also provided optimal cut-off scores for dementia stratified by age, education, and gender, which may further improve the diagnostic accuracy of the MMSE-S for dementia. CONCLUSION: Due to its good accuracy and brevity, the MMSE-S may contribute to enhancing the cost-effectiveness of and accessibility to dementia screening as well as early diagnosis and treatment of dementia, particularly in low- and middle-income countries.

Application of variable threshold intensity to segmentation for white matter hyperintensities in fluid attenuated inversion recovery magnetic resonance images.

INTRODUCTION: White matter hyperintensities (WMHs) are regions of abnormally high intensity on T2-weighted or fluid-attenuated inversion recovery (FLAIR) magnetic resonance imaging (MRI). Accurate and reproducible automatic segmentation of WMHs is important since WMHs are often seen in the elderly and are associated with various geriatric and psychiatric disorders. METHODS: We developed a fully automated monospectral segmentation method for WMHs using FLAIR MRIs. Through this method, we introduce an optimal threshold intensity (I O ) for segmenting WMHs, which varies with WMHs volume (V WMH), and we establish the I O -V WMH relationship. RESULTS: Our method showed accurate validations in volumetric and spatial agreements of automatically segmented WMHs compared with manually segmented WMHs for 32 confirmatory images. Bland-Altman values of volumetric agreement were 0.96 ± 8.311 ml (bias and 95 % confidence interval), and the similarity index of spatial agreement was 0.762 ± 0.127 (mean ± standard deviation). Furthermore, similar validation accuracies were obtained in the images acquired from different scanners. CONCLUSIONS: The proposed segmentation method uses only FLAIR MRIs, has the potential to be accurate with images obtained from different scanners, and can be implemented with a fully automated procedure. In our study, validation results were obtained with FLAIR MRIs from only two scanner types. The design of the method may allow its use in large multicenter studies with correct efficiency.

Cough in the elderly population: relationships with multiple comorbidity.

BACKGROUND: The epidemiology of cough in the elderly population has not been studied comprehensively. The present study aimed to investigate the epidemiology of cough in a community elderly population, particularly in relation with their comorbidity. METHODS: A cross-sectional analysis was performed using a baseline dataset from the Korean Longitudinal Study on Health and Aging, a community-based elderly population cohort study. Three types of cough (frequent cough, chronic persistent cough, and nocturnal cough) were defined using questionnaires. Comorbidity was examined using a structured questionnaire. Health-related quality of life was assessed using the Short Form 36 questionnaire. RESULTS: The prevalence was 9.3% for frequent cough, 4.6% for chronic persistent cough, and 7.3% for nocturnal cough. In multivariate logistic regression analyses, smoking, asthma and allergic rhinitis were found to be risk factors for cough in the elderly. Interestingly, among comorbidities, constipation and uncontrolled diabetes mellitus (HbA1c ≥ 8%) were also found to have positive associations with elderly cough. In the Short Form 36 scores, chronic persistent cough was independently related to impairment of quality of life, predominantly in the mental component. CONCLUSIONS: Cough has a high prevalence and is detrimental to quality of life in the elderly. Associations with smoking, asthma and rhinitis confirmed previous findings in younger populations. Previously unrecognised relationships with constipation and uncontrolled diabetes mellitus suggested the multi-faceted nature of cough in the elderly.

Smoking in elderly Koreans: prevalence and factors associated with smoking cessation.

The aims of this study were to investigate the prevalence of smoking and to explore the factors associated with smoking cessation. 1118 Koreans were randomly sampled from the residents aged 65 years or older living in Seongnam, Korea. Structured face-to-face interviews with neurological and physical examinations were conducted to the 714 respondents. A current smoker was defined as a person who had been smoking at least one cigarette per day for 1 year, and a past smoker as a person who used to smoke but had not smoked in the past 1 year. Nicotine dependence was defined as having the Fagerström Test for Nicotine Dependence (FTND) score of 4 or higher. Age- and gender-standardized prevalence of ever smoker, past smoker and current smoker among the elderly Koreans aged 65 and over were estimated to be 36.3% (95% CI=32.7-39.8), 24.4% (95% CI=21.2-27.5) and 11.9% (95% CI=9.5-14.3), respectively. Current smokers were much more prevalent in men (23.3%) than in women (3.9%), but did not decline with advancing age in both genders. 36.0% (21 men, 10 women) of the current smokers were nicotine-dependent. The smokers with depression or alcohol use disorder (AUD) were less likely and those who were educated more or inhaled smoke more deeply were more likely to quit smoking. Thus, smoking is common in the elderly men, and treatments of depression and AUD may be helpful in increasing smoking cessation rate among elderly Koreans.

Alcohol dependence, mortality, and chronic health conditions in a rural population in Korea.

To determine the effects of excessive drinking and alcohol dependency on mortality and chronic health problems in a rural community in South Korea, this study represents a nested case-control study. In 1998, we conducted the Alcohol Dependence Survey (ADS), a population survey of a village in Korea. To measure the effects of alcohol on chronic health conditions and mortality over time, in 2004, we identified 290 adults from the ADS sample (N=1,058) for follow-up. Of those selected, 145 were adults who had alcohol problems, either alcohol dependence as assessed in the ADS by the Severity of Alcohol Dependence Questionnaire (N=59), or excessive drinking without dependency (N=86). Further 145 nondrinkers were identified, matching those with alcohol problems in age and sex. We revisited the village in 2004 and completed personal interviews with them. In multivariate logistic regressions, the rates of mortality and morbidity of chronic health conditions were three times greater for alcohol dependents compared with the rate for nondrinkers. Importantly, however, excessive drinking without dependency was not associated with the rates of either mortality or morbidity. Future investigations would benefit by attending more specifically to measures for alcohol dependence as well as measures for alcohol consumption.