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There are growing concerns about the impact of the COVID-19 pandemic on the mental health of older adults. We examined the effect of the pandemic on the risk of depression in older adults.
We analyzed data from the prospective cohort study of Korean older adults, which has been followed every 2 years. Among the 2308 participants who completed both the third and the fourth follow-up assessments, 58.4% completed their fourth follow-up before the outbreak of COVID-19 and the rest completed it during the pandemic. We conducted face-to-face diagnostic interviews using Mini International Neuropsychiatric Interview and used Geriatric Depression Scale. We performed generalized estimating equations and logistic regression analyses.
The COVID-19 pandemic was associated with increased depressive symptoms in older adults [b (standard error) = 0.42 (0.20), p = 0.040] and a doubling of the risk for incident depressive disorder even in euthymic older adults without a history of depression (odds ratio = 2.44, 95% confidence interval 1.18–5.02, p = 0.016). Less social activities, which was associated with the risk of depressive disorder before the pandemic, was not associated with the risk of depressive disorder during the pandemic. However, less family gatherings, which was not associated with the risk of depressive disorder before the pandemic, was associated with the doubled risk of depressive disorder during the pandemic.
The COVID-19 pandemic significantly influences the risk of late-life depression in the community. Older adults with a lack of family gatherings may be particularly vulnerable.
To investigate whether amnestic mild cognitive impairment (aMCI) identified with visual memory tests conveys an increased risk of Alzheimer’s disease (risk-AD) and if the risk-AD differs from that associated with aMCI based on verbal memory tests.
4,771 participants aged 70.76 (SD = 6.74, 45.4% females) from five community-based studies, each a member of the international COSMIC consortium and from a different country, were classified as having normal cognition (NC) or one of visual, verbal, or combined (visual and verbal) aMCI using international criteria and followed for an average of 2.48 years. Hazard ratios (HR) and individual patient data (IPD) meta-analysis analyzed the risk-AD with age, sex, education, single/multiple domain aMCI, and Mini-Mental State Examination (MMSE) scores as covariates.
All aMCI groups (n = 760) had a greater risk-AD than NC (n = 4,011; HR range = 3.66 – 9.25). The risk-AD was not different between visual (n = 208, 17 converters) and verbal aMCI (n = 449, 29 converters, HR = 1.70, 95%CI: 0.88, 3.27, p = 0.111). Combined aMCI (n = 103, 12 converters, HR = 2.34, 95%CI: 1.13, 4.84, p = 0.023) had a higher risk-AD than verbal aMCI. Age and MMSE scores were related to the risk-AD. The IPD meta-analyses replicated these results, though with slightly lower HR estimates (HR range = 3.68, 7.43) for aMCI vs. NC.
Although verbal aMCI was most common, a significant proportion of participants had visual-only or combined visual and verbal aMCI. Compared with verbal aMCI, the risk-AD was the same for visual aMCI and higher for combined aMCI. Our results highlight the importance of including both verbal and visual memory tests in neuropsychological assessments to more reliably identify aMCI.
This study aimed to investigate the influences of age, education, and gender on the two total scores (TS-I and TS-II) of the Consortium to Establish a Registry for Alzheimer's Disease Neuropsychological assessment battery (CERAD-NP) and to provide normative information based on an analysis for a large number of elderly persons with a wide range of educational levels.
In the study, 1,987 community-dwelling healthy volunteers (620 males and 1,367 females; 50–90 years of age; and zero to 25 years of education) were included. People with serious neurological, medical, and psychiatric disorders (including dementia) were excluded. All participants underwent the CERAD-NP assessment. TS-I was generated by summing raw scores from the CERAD-NP subtests, excluding Mini-Mental State Examination and Constructional Praxis (CP) recall subtests. TS-II was calculated by adding CP recall score to TS-I.
Both TS-I and TS-II were significantly influenced by demographic variables. Education accounted for the greatest proportion of score variance. Interaction effect between age and gender was found. Based on the results obtained, normative data of the CERAD-NP total scores were stratified by age (six overlapping tables), education (four strata), and gender.
The normative information will be very useful for better interpretation of the CERAD-NP total scores in various clinical and research settings and for comparing individuals’ performance of the battery across countries.
Social support programs for dementia caregivers were widely used in order to reduce care burden. We investigated which types of social supports can reduce psychological and non-psychological burdens of dementia caregivers, and explored the mechanism of those social supports.
We evaluated 731 community-dwelling dementia patients and their caregivers from the National Survey of Dementia Care in South Korea. We investigated the five types of social supports (emotional support, informational support, tangible support, positive social interaction, affectionate support) using the Medical Outcomes Study Social Support Survey in each caregiver. The mechanisms of specific types of social support on psychological/non-psychological burden were examined using path analysis.
Positive social interaction and affectionate support reduced psychological burden via direct and indirect paths. Tangible support reduced the non-psychological burden via direct and indirect paths. Informational support and emotional support were not helpful for reducing psychological or non-psychological burden. A maximum of 20% of psychological burden could be relieved by positive social interaction and 10.3% of that could be reduced by affectionate support. Tangible support was associated with a 15.1% maximal improvement in non-psychological burden.
In order to reduce caregiver burden in dementia effectively, psychosocial interventions should be tailored to target type of caregiver burden.
In many countries, illiteracy rates among aged people are quite high. However, only few studies have specifically investigated the impact of illiteracy on depression.
Data for 1,890 elderly individuals (aged ≥65 years) were obtained from a nationwide dementia epidemiological study conducted in South Korea. Based on their reading ability, the participants were divided into three groups: totally illiterate, partially illiterate, and literate. The Korean version of the Geriatric Depression Scale – Short Form (SGDS-K) was used to detect depression (cut-off score = 8). Multivariate logistic regression analyses were used to assess the association between illiteracy and depression. To explore clinical features of depression in illiterate people, we performed logistic regression to calculate odds ratios of positive responses (or negative responses to reverse-coded items) for each SGDS-K item using literate individuals as the reference group.
Totally illiterate participants had 2.41 times the odds and partially illiterate individuals had 1.59 times the odds of being depressed compared with literate participants after controlling for other variables. Compared with literate individuals, illiterate elderly persons were at increased odds for responding negatively to the majority of SGDS-K items, including “having memory problems,” “others are better off than me,” and “feeling worthless” even after controlling for various demographic and clinical factors.
Illiteracy in elderly individuals was associated with a higher rate and increased severity of depression. Illiteracy negatively affected depression symptomatology, especially factors associated with self-esteem. Therefore, clinicians should carefully monitor for the presence of depression in illiterate elderly adults.
Background: Mortality associated with depression may be influenced by severity of depression and gender. We investigated the differential impacts on all-cause mortality of late-life depression by the type of depression (major depressive disorder, MDD; minor depressive disorder, MnDD; subsyndromal depression, SSD) and gender after adjusting comorbid conditions in the randomly sampled elderly.
Methods: One thousand community-dwelling elderly individuals were enrolled. Standardized face-to-face clinical interviews, neurological examination, and physical examination were conducted to diagnose depressive disorders and comorbid cognitive disorders. Depressive disorders were diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV) criteria and SSD to study-specific operational criteria. Five-year survivals were compared between groups using Cox proportional hazards models.
Results: By the end of 2010, 174 subjects (17.4%) died. Depressive disorder (p = 0.001) and its interaction term with gender (p < 0.001) were significant in predicting five-year survival. MDD was an independent risk factor for mortality in men (hazard ratio = 3.65, 95% confidence interval = 1.67–7.96) whereas MnDD and SSD were not when other risk factors were adjusted.
Conclusions: MDD may directly confer the risk of mortality in elderly men whereas non-major depression may be just an indicator of increased mortality in both genders.
Background: The influences of demographics, culture, language, and environmental changes on Mini-Mental State Examination (MMSE) scores are considerable.
Methods: Using a sample of 7452 healthy, community-dwelling elderly Koreans, aged 55 to 94 years, who participated in the four ongoing geriatric cohorts in Korea, we investigated demographic influences on MMSE scores and derived normative data for this population. Geropsychiatrists strictly excluded subjects with cognitive disorders according to the protocol of the Korean version of the Consortium to Establish a Registry for Alzheimer's Disease Assessment Packet (CERAD-K) Clinical Assessment Battery (CERAD-K-C).
Results: Education (standardized β = 0.463), age (standardized β = −0.303), and gender (standardized β = −0.057) had significant effects on MMSE scores (p < 0.001). The score of MMSE increase 0.379 point per 1-year education, decrease 0.188 per 1-year older, and decrease 0.491 in women compared to men. Education explained 30.4% of the scores’ total variance, which was much larger than the variances explained by age (8.4%) or gender (0.3%). Accordingly, we present normative data for the MMSE stratified by education (0, 1–3, 4–6, 7–9, 10–12, and ≥ 13 years), age (60–69, 70–79, and 80–89 years), and gender.
Conclusions: We provide contemporary education-, age-, and gender-stratified norms for the MMSE, derived from a large, community-dwelling elderly Korean population sample, which could be useful in evaluating individual MMSE scores.
Background: This study investigates discrepancies between the confidence expressed by Korean elders in their balance and their actual physical performances according to sex and age. It also attempts to identify the factors responsible for such gaps or discrepancies.
Methods: The Korean Longitudinal Study on Health and Aging (KLoSHA) was designed as a population-based prospective cohort study on the health and aging of Korean adults aged 65 years and over. We evaluated 1000 of 1118 randomly selected subjects in terms of activities-specific balance confidence (ABC) and performance in regard to balance and gait (POMA). Activities of daily living (ADL) and instrumental activities of daily living (IADL) were assessed to measure disability. Pain-related dysfunctions, depression and cognitive functions were assessed. Next, we assessed the relationship between balance confidence and physical performance and functioning by sex and age.
Results: The balance confidence of elderly women was lower than that of elderly men, although the physical performances of men and women under the age of 80 were similar. Women showed increased functional disability related to lower extremity pain and closely associated with balance confidence. However, psychological variables such as depression and cognitive functioning did not affect balance confidence.
Conclusion: We found a discrepancy between balance confidence and physical performance according to sex and age among Koreans elders. Low balance confidence among women elders was correlated with pain-related dysfunctions other than those reflected in POMA scores. Therefore, enhancing confidence and controlling pain as a means of preventing disability should be emphasized when developing models for maintaining and promoting health in elders.
Conventional Ge2Sb2Te5 (GST) was modified by adding up a small amount of SiOx, using co-sputtering technique from multiple targets. The SiOx content was gradually increased by increasing the power applied to SiOx target, up to 8 volume percent. The sheet resistance of SiOx-containing GST exponentially increased, when the room-temperature-deposited samples were annealed at 300 °C. Transmission electron microscopy images revealed that no SiOx particulates were formed, which was confirmed by Gattan image filtering. It was indicated by x-ray diffraction patterns that the grain size of SiOx-containing GST is smaller than normal GST with lattice locally distorted at its crystalline state, suggesting that molecular SiOx is homogeneously distributed throughout the GST matrix. We observed that the crystallization temperature of SiOx-containing GST is gradually elevated by increasing the SiOx content, while the melting point decreased. These observations led to the reset current reduction, which is a critical requirement for the high density PRAM.
In this study, we investigated the effects of the addition of CF4, Cl2, and N2 gases to oxygen electron cyclotron resonance (ECR) plasma on the reactive ion etching (RIE) properties of RuO2 film such as etch rate, selectivity, and etched profile. The concentration of the etching species in the plasma was analyzed with an optical emission spectroscopy (OES) and a quadrupole mass spectrometer (QMS). The etch product was also examined with QMS.
The addition of a small amount of CF4, Cl2, or N2 to the O2 plasma increases the concentration of oxygen radicals and accordingly increases the etch rate of the RUO2 films appreciably. The etch rate of the RuO2 film was enhanced more with the addition of a small amount of CF4 and CI2 than with the addition of N2. On the contrary, the etched profile obtained in O2/N2 plasma was superior, without any damaged layer at the sidewall, to O2/CF4 and O2/Cl2 plasma. The selectivity of RuO2 to Si)2 mask was over 20:1 for each of the additive gas proportion at which the etch rate was maximum for each plasma system.
The influence of ion bombardment on the mechanical stress and microstructure of sputtered silicon nitride (SiNx) films has been systematically investigated. Applied substrate bias voltage was used to control the bombardment energy in a radio frequency (rf) reactive magnetron sputtering system. The resultant films were characterized by transmission electron microscopy (TEM), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FT-IR), Rutherford backscattering spectrometry (RBS), stress and chemical etch rate measurements. As the bias voltage was increased, the internal stress in SiNx films became increasingly compressive and reached a value of about 18.3 × 109 dyne/cm2 at higher bias voltages. These correlated well with the transition of the film microstructure from a porous microcolumnar structure containing large void to the more densely packed one. The obtained results can be explained in terms of atomic peening by energetic particles, leading to densification of the microstructure. It was also found that the amount of argon incorporated in the film is increased with increasing bias voltage, whereas the oxygen content is decreased. The lowest etch rate in buffered HF solution, approximately 1.2 Å/sec, was observed with the application of a substrate bias of -50 V.
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