Social Mobility and Cognitive Impairment Among Korean Older Adults: Does Gender Matter?

The purpose of this study is to investigate the association between social mobility and cognitive impairment among older adults in Korea. The study sample is drawn from nationally representative data, which comes from the 2016 Korean Longitudinal Study of Ageing (KLoSA). The final sample consists of 4264 KLoSA respondents aged 65 or older. Gender-specific logistic regression models are used to examine the association between social mobility and cognitive impairment. The results show that, when compared to the reference group (stable low social mobility), women in the downward and the stable high social mobility groups were less likely to have cognitive impairment. In contrast, upward social mobility was a protective factor for cognitive impairment only among men. Gender-specific interventions may be needed to enhance cognitive health among older Koreans. Further research is needed to examine the causal relations between social mobility and cognitive health between the genders.

Multi-group frailty trajectories among older Koreans: Results from the Korean Longitudinal Study of Aging.

BACKGROUND: Studies that examined changes in frailty in older populations have been increasing. However, frailty patterns are often portrayed as having single trajectories corresponding to age, and different courses of change in frailty and related factors remain unexplored. OBJECTIVES: We aimed to identify distinct frailty trajectories over time and examine the relationship of frailty trajectories with the sociodemographic and lifestyle-related factors among older Koreans. METHODS: We used data of 3160 community-dwelling Korean adults aged ≥65 years from the Korean Longitudinal Study of Aging (2006-2016). We conducted the analyses using group-based trajectory modeling, analysis of variance or chi-square tests, and multinomial logistic regression. RESULTS: We identified three frailty trajectory groups among older Koreans: no frailty, increasing frailty, and high frailty based on a deficit-related frailty measure. Each frailty trajectory group showed unique sociodemographic and lifestyle characteristics. Compared to individuals in the no frailty group, those in the increasing frailty group were more likely to be older, less educated, unemployed, current smokers, and current drinkers. Compared to those in the no frailty group, individuals in the high frailty group were more likely to be older, unemployed, current drinkers, and without regular exercise. CONCLUSIONS: Using longitudinal data over a 10-year period, we identified multiple frailty trajectories in a cohort of older Koreans, which highlights a significant heterogeneity in frailty development. Our findings suggest the importance of socioeconomic status in determining different patterns of frailty change and the role of lifestyle factors in delaying frailty.

Body mass index, subjective body shape, and suicidal ideation among community-dwelling Korean adults.

BACKGROUND: Previous studies have not investigated in depth the combination of objective body weight and subjective body shape and its association with suicidal ideation among different age groups. Therefore, this study aimed to examine the abovementioned association among Korean adults, stratified by developmental stages. METHODS: We used nationally representative data from the 2017 Korean Community Health Survey, and included 222,037 participants aged 19 years or older in our study. Suicidal ideation was considered as the dependent variable (1 = yes, 0 = no). Along with body mass index (BMI) and subjective body shape measures, seven categories were created (1 = underweight-skinny, 2 = underweight-normal/fat, 3 = healthy weight-skinny, 4 = healthy weight-normal, 5 = healthy weight-fat, 6 = overweight-skinny/normal, 7 = overweight-fat). Multivariate logistic regression was conducted for each age group. RESULTS: Adjusted for covariates, young adults who were overweight-fat (OR = 1.18, p < .01), middle-aged adults who were underweight-skinny (OR = 1.32, p < .05), and older adults who were healthy weight-fat (OR = 1.19, p < .05) were more likely to have suicidal ideation than their healthy weight-normal counterparts. CONCLUSIONS: The results suggest that the association between the combination of objective body weight and subjective body shape and suicidal ideation differs according to the developmental stage. Therefore, this difference should be considered when developing suicide prevention interventions based on the developmental stages.

Body mass index and trajectories of cognitive decline among older Korean adults.

Objectives: This study examined the relationship between body mass index (BMI) and trajectories of cognitive decline among older Korean adults.Methods: Participants were a nationally representative sample of 5126 Korean adults aged 60 or older from the Korean Longitudinal Study of Aging (KLoSA: 2006-2014). The main outcome variable, cognitive function, was measured with the Korean Mini-Mental State Examination (K-MMSE). According to the BMI values, respondents were divided into four groups at each wave: underweight (<18.5 kg/m2), healthy weight (18.5-22.9 kg/m2), overweight (23.0-24.9 kg/m2), and obese (≥25.0 kg/m2). Growth curve modeling was used to analyze the relationship of interest.Results: The growth curve modeling revealed that, regardless of BMI values, cognitive functioning declined as participants aged, and the rate of cognitive decline accelerated with age. After adjusting for all covariates, older Korean adults who were underweight displayed steeper declines in cognitive functioning, compared to those with a healthy weight. Conversely, overweight or obese older adults showed a much slower cognitive decline as they aged, after adjusting for covariates.Conclusion: Compared to people with a healthy BMI, people with a low BMI may be at risk for cognitive dysfunction, whereas a high BMI could function as a protective factor for cognitive dysfunction in older adulthood. Future research examining the mechanism for these trajectories are needed. Implications for research and clinical practice are discussed.

Trajectories of cognitive decline by widowhood status among Korean older adults.

OBJECTIVES: Given the limited evidence regarding the longitudinal impact of widowhood on cognitive function in later life, the present study aimed to investigate the longitudinal effect of widowhood status on cognitive change among Korean older adults. METHODS: The study sample was drawn from a nationally representative data set, the Korean Longitudinal Study of Ageing (KLoSA); it consisted of 3,660 Korean adults aged 60 and over who were married at baseline. Our dependent variable, cognitive function, was measured by the Korean version of the Mini-Mental State Examination (K-MMSE). Widowhood status was measured with the combination of widowhood status and duration. Growth curve models were constructed using five waves of the KLoSA (2006-2014) to examine the longitudinal trajectories of cognitive changes. RESULTS: In the unadjusted model, widowed older adults had significantly lower cognitive function than their nonwidowed counterparts regardless of widowhood duration. Adjusting for covariates, results from the growth curve models showed that widowed older adults with widowhood duration 4 to 6 years had a significantly steeper decline in cognitive function than nonwidowed older adults (P < 0.05). CONCLUSIONS: These findings suggest that widowhood is detrimental for late-life cognitive function. Further research is required to understand the mechanisms underlying this relationship. Policy and practice implications are discussed according to the cultural context.

Volunteering among First-Generation Asian Ethnic Groups Residing in California.

This study was a cross-sectional investigation of volunteer activity among four distinct Asian ethnic subgroups-Chinese, Filipino, Korean, and Vietnamese-who have immigrated to the United States. Data from the 2011-2012 California Health Interview Survey (CHIS) were used with an analytic sample of Chinese (n = 547), Filipino (n = 229), Korean (n = 490), and Vietnamese (n = 546) adults 50 and older. A series of logistic regression models were estimated to examine differences and similarities across the four ethnic groups in volunteer activity. Consistent with previous studies, Asian immigrants with more years of education and those who became U.S. citizens were more likely to participate in volunteering. However, the correlates were not consistent within Asian ethnic subgroups. For example, education was not a significant factor for older Korean immigrants while it was a salient factor among other Asian subgroups. Results showed similarities and differences associated with volunteer participation among diverse ethnic subgroups. The findings underscored the importance of culture-specific information in creating inclusive opportunities for volunteering.

Gender-Specific Associations of Sensory Impairments with Depression and Cognitive Impairment in Later Life.

OBJECTIVE: Sensory impairments, such as vision and hearing impairments, increase with age, and studies have shown that self-reported vision and hearing impairments are associated with adverse mental health outcomes in later life. Although gender differences may exist in the associations between sensory impairments and geriatric mental health outcomes, little research has been done examining gender differences in the above associations. Therefore, the purpose of this study was to investigate the relationship between self-reported sensory impairments and geriatric mental health outcomes with the aim of determining whether any association differs by gender. METHODS: The study sample was drawn from a nationally representative data set, the 2012 Korean Longitudinal Study of Ageing, and the final sample consisted of 2,167 females and 1,664 males aged 65 and over. Self-reported sensory impairments were categorized into four groups: no sensory impairment (reference), vision impairment only, hearing impairment only, and dual sensory impairment. Depression and cognitive impairment were used as dependent variables in separate analyses. RESULTS: Adjusted for confounding variables, results from a multivariate analysis showed that vision impairment was significantly associated with depression only among women. Moreover, hearing impairment was significantly associated with cognitive impairment for women, but not for men. Having dual sensory impairment was associated with depression only among men, while having dual sensory impairment was associated with cognitive impairment only among women. CONCLUSION: These findings suggest that the associations between sensory impairments and geriatric mental health outcomes vary according to gender. Therefore, gender-specific strategies in healthcare policies are needed.

Childhood Misfortune and Adult Health in a National Study.

This study investigated the relationship between childhood misfortune and 10-year change in health and whether this relationship was mediated by the quality of social relations. We used data from the Midlife in the United States (MIDUS) national longitudinal study, 1995-1996 (Time 1) and 2005-2006 (Time 2). Childhood misfortune was measured at Time 1 using indicators of financial strain, family structure, and abuse. Self-rated physical and mental health indicators were obtained at both occasions. The measure of quality of social relations was based on items relative to social support and social strain from spouse, friends, and family at Time 1. Mediational models showed that a higher level of childhood misfortune was associated with low-quality family relations which in turn tend to account for change in mental health. These findings suggest that childhood misfortune is associated with the quality of social relations, which in turn explain individual changes in mental health in adulthood.

Gender-Specific Incidence and Predictors of Cognitive Impairment among Older Koreans: Findings from a 6-Year Prospective Cohort Study.

OBJECTIVE: This study investigated gender-specific incidence and predictors of cognitive impairment among community-dwelling older adults in South Korea. METHODS: Using data from the 2006 and 2012 Korean Longitudinal Study of Ageing (KLoSA), 925 females and 834 males aged 65 and over without cognitive impairment at 2006 were analyzed separately. Cognitive impairment was measured based on the Korean version of the Mini-Mental State Exam (K-MMSE) normative score. Generalized Estimating Equations (GEE) was conducted to examine the predictors of cognitive impairment at 6-year follow up. RESULTS: Incidence of cognitive impairment at 2012 was significantly higher for women (30.5%) than men (26.1%). GEE result showed that depression was significantly associated with cognitive impairment for both genders (female: OR=2.26, 95% CI=1.63-3.12; male: OR=3.26, 95% CI=2.19-4.83). Having IADL limitations (OR=1.15, 95% CI=1.03-1.28), high blood pressure (OR=1.72, 95% CI=1.27-2.34), poor hearing (OR=1.94, 95% CI=1.29-2.92), regular exercise (OR=0.67, 95% CI=0.45-0.99), and normal weight (OR=1.39, 95% CI=1.03-1.86) were significant predictors of cognitive impairment only among women. In contrast, age (OR=1.04, 95% CI=1.01-1.07) and ADL limitations (OR=1.48, 95% CI=1.21-1.82) were significant predictors of cognitive impairment at follow-up only among men. CONCLUSION: Findings of this study show gender-specific predictors of cognitive impairment among older Koreans. This study can provide information for clinicians and policy makers to develop different intervention strategies considering gender differences in the progress of cognitive impairment.

Socioeconomic Status Across the Life Course and Cognitive Function Among Older Adults: An Examination of the Latency, Pathways, and Accumulation Hypotheses.

OBJECTIVE: This study investigated the relationship between life course socioeconomic status (SES) and cognitive function among older adults in the United States over a 12-year observation period. The mediation of adult SES on the association between childhood SES and cognition was examined, along with the relationship between cumulative SES and cognition. METHOD: Using a nationally representative sample from the Health and Retirement Study, cognitive status and change in cognition from 1998 to 2010 were examined using growth curve models. RESULTS: The results showed that cognitive function varied within-persons and between-persons. SES disadvantage in childhood was associated with lower cognitive function at baseline. Adult SES mediated the relationship between childhood SES and cognitive function. Persons with higher cumulative SES demonstrated an advantage in cognitive function. DISCUSSION: Childhood SES and adult SES both had relationships with cognitive status and, to a lesser degree, change in cognition in later life.

Associations between healthy lifestyles and health outcomes among older Koreans.

AIM: Healthy lifestyles have been found to be positively associated with physical and mental health outcomes in later life. Although multiple health behaviors have the potential to enhance health among older adults, little is known about a multiple behavior approach. Therefore, the purpose of the present study was to examine the relationship between multiple healthy lifestyles and health outcomes among Korean older adults. METHODS: The study sample consisted of 3844 Korean older adults aged 65 years and older from a cross-section sample being followed in the nationally representative dataset, the 2012 Korean Longitudinal Study of Ageing. Healthy lifestyles included non-smoking, normal drinking, physical activity and normal weight. Adjusting for covariates (age, sex, marital status, education, household income and having chronic condition), a multivariate logistic regression was carried out to examine self-rated health, disability, cognitive impairment and depression as four individual health outcomes. RESULTS: Compared with respondents with no healthy lifestyle factors, respondents with at least one healthy lifestyle factor had better self-rated health, respondents with at least two healthy lifestyle factors had reduced risk of disability, and respondents with at least three healthy lifestyle factors had reduced risk of cognitive impairment. Interestingly, having just two or three healthy lifestyle factor was associated with reduced risk of depression. CONCLUSIONS: These results suggest that older Koreans with more healthy lifestyles are healthier than those with less healthy lifestyles. Also, the association between multiple healthy lifestyle factors and health outcomes is different by specific health outcome, showing different mechanisms between multiple healthy lifestyle factors and each health outcome. Geriatr Gerontol Int 2015; ●●: ●●-●●.

Risk factors related to cognitive functioning: a cross-national comparison of U.S. and Korean older adults.

The purpose of this study was to conduct a cross-national comparison of factors related to cognitive functioning in later life in a U.S. and Korean sample. The study sample was comprised of subjects from the HRS (N = 10,175) and the KLoSA (N = 3,550). Separate multivariate regression models were employed to examine the impact of socio-demographic, health, and health behaviors on cognitive functioning among older adults. Regression results showed that age, gender, education, wealth, self-rated health, ADL, IADL, stroke, and poor eyesight were significantly associated with cognitive functioning in both countries. However, depression, high blood pressure, diabetes, and drinking were significantly associated with cognition only among Americans, while marital status and poor hearing were significantly associated with cognition only among Koreans. In addition, gender-specific models suggested several socio-economic and health factors had significantly different effects by gender in both countries. Cross-national comparative research identified similar risk factors, suggesting robust associations. Unique factors related to cognitive functioning in U.S. and Korean older adults highlight the important role of societal influences on cognitive outcomes.

Risk factors related to cognitive functioning: a cross-national comparison of U.S. and Korean older adults.

The purpose of this study was to conduct a cross-national comparison of factors related to cognitive functioning in later life in a U.S. and Korean sample. The study sample was comprised of subjects from the HRS (N = 10,175) and the KLoSA (N = 3,550). Separate multivariate regression models were employed to examine the impact of socio-demographic, health, and health behaviors on cognitive functioning among older adults. Regression results showed that age, gender, education, wealth, self-rated health, ADL, IADL, stroke, and poor eyesight were significantly associated with cognitive functioning in both countries. However, depression, high blood pressure, diabetes, and drinking were significantly associated with cognition only among Americans, while marital status and poor hearing were significantly associated with cognition only among Koreans. In addition, gender-specific models suggested several socio-economic and health factors had significantly different effects by gender in both countries. Cross-national comparative research identified similar risk factors, suggesting robust associations. Unique factors related to cognitive functioning in U.S. and Korean older adults highlight the important role of societal influences on cognitive outcomes.

Alcohol consumption and cognitive impairment among Korean older adults: does gender matter?

BACKGROUND: This study investigated gender differences in the relationship between alcohol consumption and cognitive impairment among older adults in South Korea. METHODS: Using data from the Korean Longitudinal Study of Ageing, 2,471 females and 1,657 males were analyzed separately. Cognitive impairment was measured based on the Korean version of the Mini-Mental State Exam score. Logistic regression was conducted to examine the relationship between alcohol consumption and cognitive impairment among Korean older adults. RESULTS: Multivariate analysis showed that compared to moderate drinkers, past drinkers were more likely to be cognitively impaired for women, while heavy drinkers were more likely to be cognitively impaired for men. CONCLUSIONS: Findings suggest that the relationship between alcohol consumption and cognition varies with gender. Clinicians and service providers should consider gender differences when developing strategies for the prevention and treatment of alcohol-related cognitive decline among older adults.

Intergenerational financial exchange and the psychological well-being of older adults in the Republic of Korea.

OBJECTIVES: This study examined whether the exchange of instrumental support (i.e., financial resources) among older adults and their children was related to the psychological well-being of older Koreans. METHODS: Data from the Korean Longitudinal Study of Ageing were employed. Older adults who were aged 65 and older and who had at least one living child who did not live in the respondent's household were included (N = 3791). Well-being was measured with depressive symptoms (CES-D-10) and life satisfaction. For the direction model of exchange, giving and receiving support was assessed with financial aid (cash and non-cash). For the reciprocity model of exchange, four patterns of financial exchanges were identified: both giving and receiving, receiving only, giving only, and no exchange. RESULTS: The results from the direction model showed that older adults who give financial support were less likely to be depressed and reported higher levels of life satisfaction. The effect of receiving support was not significant for depression but was related to higher levels of life satisfaction. The results from the reciprocity model showed that those who gave and received support had better psychological health compared to those who only received support. CONCLUSIONS: Both giving and receiving were positively related to the psychological well-being of older adults. Our results provide support for identity theory and equity theory as frameworks for understanding intergenerational exchange and well-being of older Koreans.

Statistical methods used in articles published by the Journal of Periodontal and Implant Science.

PURPOSE: The purposes of this study were to assess the trend of use of statistical methods including parametric and nonparametric methods and to evaluate the use of complex statistical methodology in recent periodontal studies. METHODS: This study analyzed 123 articles published in the Journal of Periodontal & Implant Science (JPIS) between 2010 and 2014. Frequencies and percentages were calculated according to the number of statistical methods used, the type of statistical method applied, and the type of statistical software used. RESULTS: Most of the published articles considered (64.4%) used statistical methods. Since 2011, the percentage of JPIS articles using statistics has increased. On the basis of multiple counting, we found that the percentage of studies in JPIS using parametric methods was 61.1%. Further, complex statistical methods were applied in only 6 of the published studies (5.0%), and nonparametric statistical methods were applied in 77 of the published studies (38.9% of a total of 198 studies considered). CONCLUSIONS: We found an increasing trend towards the application of statistical methods and nonparametric methods in recent periodontal studies and thus, concluded that increased use of complex statistical methodology might be preferred by the researchers in the fields of study covered by JPIS.

Gender differences in the link between excessive drinking and domain-specific cognitive functioning among older adults.

OBJECTIVE: This study investigated gender differences in the relationship between excessive drinking and two cognitive domains among older adults. METHOD: Using data from the Health and Retirement Study, 3,888 females and 2,350 males were analyzed separately. Multivariate regression was used to analyze the association between excessive drinking and fluid intelligence score. Logistic regression was conducted to examine the relationship between excessive drinking and crystallized intelligence. RESULTS: Multivariate analysis showed that compared to non-excessive drinking, excessive drinking did not have a significant impact on fluid intelligence for either women or men, but it had a significantly negative association with a high crystallized intelligence score for women. DISCUSSION: Findings suggest that the relationship between excessive drinking and cognition varies with gender when crystallized intelligence is measured. Clinicians and service providers should consider gender differences when developing strategies for the prevention and treatment of alcohol-related cognitive decline among older adults.