Joung Hwan Back

Systematic review of health behavioral risks and cognitive health in older adults

BACKGROUND An increasing body of evidence suggests that health behaviors may protect against cognitive impairment and dementia. The purpose of this study was to summarize the current evidence on health behavioral factors predicting cognitive health through a systematic review of the published literature. METHODS PubMed, Embase, and PsycINFO databases were searched for studies on community representative samples aged 65 and older, with prospective cohort design and multivariate analysis. The outcome--cognitive health--was defined as a continuum of cognitive function ranging from cognitive decline to impairment and dementia, and health behaviors included physical activity, smoking, alcohol drinking, body mass index, and diet and nutrition. RESULTS Of 12,105 abstracts identified, 690 relevant full-texts were reviewed. The final yield amounted to 115 articles of which 37 studies were chosen that met the highest standards of quality. Leisure time physical activity, even of moderate level, showed protective effects against dementia, whereas smoking elevated the risk of Alzheimers disease. Moderate alcohol consumption tended to be protective against cognitive decline and dementia, but nondrinkers and frequent drinkers exhibited a higher risk for dementia and cognitive impairment. Midlife obesity had an adverse effect on cognitive function in later life. Analysis showed vegetable and fish consumption to be of benefit, whereas, persons consuming a diet high in saturated fat had an increased dementia risk. CONCLUSION The review demonstrates accumulating evidence supporting health behavioral effects in reducing the risk of cognitive decline and dementia. Results indicate potential benefits of healthy lifestyles in protecting cognitive health in later life.

Gender differences in the association between socioeconomic status (SES) and depressive symptoms in older adults.

With rapid population aging, increasing attention is given to the mental health of older people. This study examined the association between SES and depressive symptoms in older adults. The study population consisted of a representative community sample of 4165 persons aged 65 and older from Wave 1 of the Korean Longitudinal Study of Aging. The Center for Epidemiologic Studies Depression scale was used to measure the extent of depressive symptoms. Socioeconomic indicators included education, household income, and net worth. Analyses were conducted by gender, using multiple linear regression analysis, to identify independent effects of socioeconomic variables on depressive symptoms, controlling for demographics and health-related variables. There was an inverse association between higher levels of socioeconomic factors and depressive symptoms in the study population. A clear difference in the association between depressive symptoms and socioeconomic factors by gender was observed. In the multivariate analysis, wealth was significantly associated with depressive symptoms in men, whereas education and income was so in women. Gender disparities in depressive symptoms across social gradients suggest the need for gender-sensitive investments in health and social services for the disadvantaged segments of the older population.

A new classification system for ischemia using a combination of deep and periventricular white matter hyperintensities.

The Clinical Research Center for Dementia of South Korea (CREDOS) group developed a new classification system for ischemia using a combination of deep and periventricular white matter hyperintensities (WMHs). In this study, we aimed to evaluate the validity of the CREDOS ischemia classification system. A total of 352 patients with cognitive impairments were included. Their WMH scores were rated using the CREDOS WMH visual rating scale. These patients were divided into 3 groups according to the CREDOS ischemia classification system. The volume of WMH was also automatically measured. The number of lacunes and microbleeds (MBs) were counted. The CREDOS ischemia classification system was revised with factor analysis using vascular risk factors and cerebrovascular disease (CVD) markers (WMH volume, lacunes, and MBs). External validation was performed in another group of patients with cognitive impairment using multinomial logistic regression analysis. The CREDOS WMH visual rating scale showed excellent correlation with the automatically measured volume of WMH. The factor analysis showed that the severe group was expanded to D3P1 and D3P2 in the revised CREDOS ischemia classification system. In the validation group, the presence of vascular risk factors and the severity of CVD markers could be distinguished according to the revised CREDOS ischemia classification. We validated a newly developed classification system for ischemia. This simple visual classification system was capable of providing information on vascular risk factors and CVD markers by simply rating WMH on magnetic resonance imaging.

The influence of multiple lifestyle behaviors on cognitive function in older persons living in the community

OBJECTIVE This study aimed to examine the influence of multiple lifestyle behaviors on cognitive function in older persons living in an urban community. METHOD A representative sample of 977 persons aged 65 and older in Suwon, Korea were interviewed in 2001, with follow-up interviews completed on 645 (2002) and 537 (2003). Lifestyle behaviors included physical activity, non-smoking, vegetable consumption, and social activity. Individual, as well as, the number and combination of health behavioral profiles were considered. Cognitive function was assessed by the Korean version of the Mini-Mental State Examination. Linear regression with generalized estimating equations was used in the analysis, controlling for sociodemographics and chronic conditions. RESULTS All lifestyle behaviors showed independent association with cognitive ability, even after adjusting for the covariates. An incremental benefit of multiple lifestyle behaviors was evident, with those engaging in more positive behaviors exhibiting a tendency to have a higher cognitive score. A two- or three-factor combination of non-smoking, vegetable consumption, and social activity showed the strongest association with cognitive function. CONCLUSION Participation in healthy lifestyles may contribute to the maintenance of cognitive function in later life. It underlines the potential benefit of multiple behaviors in promoting cognitive health of older persons.

Participation in Physical, Social, and Religious Activity and Risk of Depression in the Elderly: A Community-Based Three-Year Longitudinal Study in Korea

Background We examined the longitudinal association between participation in individual or combinations of physical, social, and religious activity and risk of depression in the elderly. Methods Elderly subjects aged ≥60 years who completed the Living Profiles of Older People Survey in Korea (n = 6,647) were included. The baseline assessment, Wave 1, was conducted in 2008, and a follow-up assessment, Wave 2, was conducted in 2011. We defined participation in frequent physical activity as ≥3 times weekly (at least 30 minutes per activity). Frequent participation in social and religious activity was defined as ≥1 activity weekly. The primary outcome was depression at 3-year follow up. Results Multivariable logistic regression analysis showed that subjects who participated in frequent physical, social, and religious activity had an adjusted odds ratio of 0.81 (95% confidence interval [CI], 0.69–0.96), 0.87 (95% CI, 0.75–1.00), and 0.78 (95% CI, 0.67–0.90), respectively, compared with participants who did not participate in each activity. Participants who participated in only one type of activity frequently and participants who participated in two or three types of activities frequently had an adjusted odds ratio of 0.86 (95% CI, 0.75–0.98) and 0.64 (95% CI, 0.52–0.79), respectively, compared with participants who did not participate in any type of physical, social, and religious activity frequently. Conclusion Participation in physical, social, and religious activity was associated with decreased risk of depression in the elderly. In addition, risk of depression was much lower in the elderly people who participated in two or three of the above-mentioned types of activity than that in the elderly who did not.

Effects of education on the progression of early- versus late-stage mild cognitive impairment.

BACKGROUND Highly educated participants with normal cognition show lower incidence of Alzheimers disease (AD) than poorly educated participants, whereas longitudinal studies involving AD have reported that higher education is associated with more rapid cognitive decline. We aimed to evaluate whether highly educated amnestic mild cognitive impairment (aMCI) participants show more rapid cognitive decline than those with lower levels of education. METHODS A total of 249 aMCI patients enrolled from 31 memory clinics using the standard assessment and diagnostic processes were followed with neuropsychological evaluation (duration 17.2 ± 8.8 months). According to baseline performances on memory tests, participants were divided into early-stage aMCI (-1.5 to -1.0 standard deviation (SD)) and late-stage aMCI (below -1.5 SD) groups. Risk of AD conversion and changes in neuropsychological performances according to the level of education were evaluated. RESULTS Sixty-two patients converted to AD over a mean follow-up of 1.43 years. The risk of AD conversion was higher in late-stage aMCI than early-stage aMCI. Cox proportional hazard models showed that aMCI participants, and late-stage aMCI participants in particular, with higher levels of education had a higher risk of AD conversion than those with lower levels of education. Late-stage aMCI participants with higher education showed faster cognitive decline in language, memory, and Clinical Dementia Rating Sum of Boxes (CDR-SOB) scores. On the contrary, early-stage aMCI participants with higher education showed slower cognitive decline in MMSE and CDR-SOB scores. CONCLUSIONS Our findings suggest that the protective effects of education against cognitive decline remain in early-stage aMCI and disappear in late-stage aMCI.

Perceived sleep quality is associated with depression in a Korean elderly population

Our study aimed to examine the relationship between perceived sleep quality and depression using Pittsburgh Sleep Quality Index (PSQI) and Coles model to materialize the concept of perceived sleep quality in the non-cognitively impaired elderly. Older adults aged 60+ were recruited from the baseline study of Suwon Project (SP) between 2009 and 2011 (n=2040). Perceived sleep quality was measured using the Korean version of the Pittsburgh Sleep Quality Index (PSQI-K), and depression was accessed using the Korean version of the Geriatric Depression Scale-Short Form (SGDS-K). We excluded the cognitively impaired elderly using the Korean version-Mini Mental Status Examination (K-MMSE) score less than or equal to 17. In multivariable adjusted logistic regression related to PSQI-K components, poor perceived sleep quality, including poor subjective sleep quality (Odds ratio (OR)=1.27, 95% confidence interval (CI)=1.01-1.61), longer sleep latency (OR=1.32, 95% CI=1.13-1.55) and the frequent use of sleeping medication (OR=1.30, 95% CI=1.10-1.53) were significantly associated with depression after adjusting for age, sex, education, living status, current smoking and current alcohol drinking, the number of comorbidity and Beck Anxiety Inventory (BAI). PSQI-K global score also had greater odds of reporting depression (OR=1.12, 95% CI=1.07-1.16). These results suggested that poor perceived sleep quality was associated with a greater level of depression in the elderly.

Multiple Socioeconomic Risks and Cognitive Impairment in Older Adults

Background/Aim: To investigate the multiple effects of socioeconomic factors on cognitive impairment in older persons. Methods: Subjects were a nationally representative sample (n = 4,155) aged ≧65 years of the Korean Longitudinal Study of Aging. Cognitive status was assessed by the Mini-Mental State Examination. Education, income, wealth and occupation were measured, with low levels on each factor combined to produce an aggregate risk score. Multiple logistic regression was used to analyze the combined effects of socioeconomic risks on cognitive impairment. Results: A socioeconomic risk gradient was evident, with the combined effect being stronger than any one of the risk factors acting alone. Compared with those with no risks, the odds ratios were 2.4 (for 2 socioeconomic risks), 3.4 (3 risks) and 7.7 (4 risks) for men, and 2.8 (2 risks), 3.5 (3 risks) and 5.4 (4 risks) for women. For individual socioeconomic risks, income and occupation were significant predictors of cognitive impairment in men, whereas in women, all 4 factors were independently associated. Conclusion: Multiple socioeconomic risks have a combined effect on cognitive impairment in older adults.

Changes in combined lifestyle risks and disability transition in older adults: Korean Longitudinal Study of Aging, 2006-2008.

OBJECTIVE This study examined associations between changes in lifestyle risks and disability in late life. METHODS A national sample of Koreans aged ≥ 65 years was surveyed at baseline (2006) and 2-year follow-up (n=3511). Disability transition was categorized as disability-free, improved, maintained, and declined, based on activities of daily living (ADL) and instrumental ADL (IADL) scales. Lifestyle risk factors included current smoking, heavy alcohol consumption, low physical activity, and unhealthy weight. Changes in lifestyle risks were categorized as risk-free, positive (decreased risk), stable, and negative (increased risk). Multinomial logistic regression models examined the influence of changes in lifestyle risks on disability transition. RESULTS A higher percentage (82.9%) of respondents who were risk-free remained disability-free than those who exhibited positive (71.8%), stable (64.9%), or negative (63.8%) change (p<0.001). Sustaining no lifestyle risks, compared with negative change, was associated with a higher likelihood of remaining disability-free than decline (odds ratio=2.68, 95% confidence interval (CI): 1.32-5.42), adjusting for covariates. Among individual lifestyle factors, physical activity was predictive of not only functional independence but also improvement and maintenance. CONCLUSIONS Older adults adopting more healthy lifestyles are more likely to maintain functional independence than decline. Making healthy lifestyle choices may delay disability progression in later life.

Clustering of multiple healthy lifestyles among older Korean adults living in the community.

Aim:  Despite the predictive value of combined healthy lifestyles in maintaining physical and cognitive functioning in late life, little is known about the clustering patterns of healthy lifestyle behaviors in older people. The aim of the present study was to examine the prevalence, clustering and population characteristics of adherence to multiple health behaviors in community‐dwelling older Korean adults.