The Mediation Effect of Self-Report Physical Activity Patterns in the Relationship between Educational Level and Cognitive Impairment in Elderly: A Cross-Sectional Analysis of Chilean Health National Survey 2016-2017

Healthy aging meta-analyses and scoping review of risk factors across Latin America reveal large heterogeneity and weak predictive models

Models of healthy aging are typically based on the United States and Europe and may not apply to diverse and heterogeneous populations. In this study, our objectives were to conduct a meta-analysis to assess risk factors of cognition and functional ability across aging populations in Latin America and a scoping review focusing on methodological procedures. Our study design included randomized controlled trials and cohort, case-control and cross-sectional studies using multiple databases, including MEDLINE, the Virtual Health Library and Web of Science. From an initial pool of 455 studies, our meta-analysis included 38 final studies (28 assessing cognition and 10 assessing functional ability, n = 146,000 participants). Our results revealed significant but heterogeneous effects for cognition (odds ratio (OR) = 1.20, P = 0.03, confidence interval (CI) = (1.0127, 1.42); heterogeneity: I2 = 92.1%, CI = (89.8%, 94%)) and functional ability (OR = 1.20, P = 0.01, CI = (1.04, 1.39); I2 = 93.1%, CI = (89.3%, 95.5%)). Specific risk factors had limited effects, especially on functional ability, with moderate impacts for demographics and mental health and marginal effects for health status and social determinants of health. Methodological issues, such as outliers, inter-country differences and publication bias, influenced the results. Overall, we highlight the specific profile of risk factors associated with healthy aging in Latin America. The heterogeneity in results and methodological approaches in studying healthy aging call for greater harmonization and further regional research to understand healthy aging in Latin America.

Education, Social Engagement, and Cognitive Function: A Cross-Lagged Panel Analysis

OBJECTIVES

Although education and social engagement are considered cognitive reserves, the pathway of both reserves on cognitive function has been rarely studied. This study aimed to examine the underlying mechanism between education, social engagement, and cognitive function.

METHODS

This study used 2-wave data (2010 and 2014) from Health and Retirement Study in the United States (N = 3,201). Education was measured by years of schooling. Social engagement was evaluated by 20 items including volunteering, physical activities, social activities, and cognitive activities. Cognitive function was assessed by a modified Telephone Interview for Cognitive Status. A cross-lagged panel model was fitted to test the mediating mechanism between education, social engagement, and cognitive function.

RESULTS

Controlling for covariates, higher education in early life was associated with better cognitive function in old age (b = 0.211, 95% confidence interval [CI] = [0.163, 0.259], p < .01). Late-life social engagement partially mediated the association between education and cognitive function (indirect effect = 0.021, 95% CI = [0.010, 0.033], p < .01). The indirect path between education and social engagement via cognition also existed (b = 0.009, 95% CI = [0.005, 0.012], p < .001).

DISCUSSION

Education in earlier life stage may exert a lifelong effect on cognitive function as well as an indirect effect via enhancing late-life cognitive reserve such as social engagement. The cross-lagged effect of social engagement on cognitive function is significant and vice versa. Future research may explore other cognitive reserves over the life course and its underlying mechanism to achieve healthy cognitive aging.

Gut Microbiota and Breast Cancer: The Dual Role of Microbes

Breast cancer is the most frequently diagnosed cancer and also one of the leading causes of mortality among women. The genetic and environmental factors known to date do not fully explain the risk of developing this disease. In recent years, numerous studies have highlighted the dual role of the gut microbiota in the preservation of host health and in the development of different pathologies, cancer among them. Our gut microbiota is capable of producing metabolites that protect host homeostasis but can also produce molecules with deleterious effects, which, in turn, may trigger inflammation and carcinogenesis, and even affect immunotherapy. The purpose of this review is to describe the mechanisms by which the gut microbiota may cause cancer in general, and breast cancer in particular, and to compile clinical trials that address alterations or changes in the microbiota of women with breast cancer.

Neighbourhood walkability and mental health in older adults: A cross-sectional analysis from EpiFloripa Aging Study

This study aims to analyse the association between walkability index and depressive symptoms and cognitive impairment and test the mediating role of moderate-vigorous physical activity (MVPA) in this relationship among older adults from Florianópolis, Brazil. This is cross-sectional research with data from the third wave of the EpiFloripa Aging cohort study, conducted in 2017–2019. Depressive symptoms were assessed using the short version of the Geriatric Depression Scale (GDS), and cognitive impairment, using the Mini-Mental State Examination (MMSE) scales. The neighbourhood environment was assessed using a walkability index, which considered 500-m network buffers around the participants’ homes. Binary logistic regression analysis the association between the walkability index (quartile) and mental health outcomes (yes vs. no). Structural equation modelling evaluated the mediation between the walkability index and cognitive impairment by MVPA with an estimator of dichotomous variables. 1,162 people participated in the study (61.5% women, average age = 73.1). Older adults residing in places with a high and highest walkability index were 38% and 44% less likely to have cognitive impairment, respective. There was no association between depressive symptoms and walkability index in crude nor adjusted analysis. Engaging in MVPA had a partial but not significant effect (14%; p = 0.087), showing a tendency for this relationship to be partially explained by the greater engagement in physical activities in places with greater walkability. Policy planning to prevent and reduce the risks of cognitive impairment should consider factors of the physical environment as determinants in older adults.

Education and grip strength among older Thai adults: A mediation analysis on health-related behaviours

Abstract.

BACKGROUND

Previous studies have investigated the effect of differential educational attainment at younger ages on health disparities among older adults, but how such an effect can be attenuated remains understudied. This study examines the mediating effects of four health-related behaviours, namely smoking, alcohol drinking, healthy eating, and physical activity, on the relationship between older adults' education and grip strength.

METHODS

The study used data from 7,064 individuals aged 60 years and older who participated in the 2009 National Health Examination Survey of Thailand. To examine the relationships among education, health behaviours, and grip strength, multivariate regressions were performed following Baron and Kenny's approach. Generalized Structural Equation Modelling (SEM) was utilized to quantify the mediating effects.

RESULTS

All else being equal, education is positively associated with stronger grip for both genders. The mediation analyses demonstrate that health-related behaviour plays an important role in the relationship between education and grip strength; however, the extent to which it mediates the effect of education varies with the type of health behaviour and between genders. Not smoking and engaging in physical activity can partly explain the relationship between education and grip strength in older men. Meanwhile, the consumption of fruits and vegetables and participation in regular physical activity significantly mediate the effect of education on grip strength in older women.

CONCLUSION

Our study reaffirms the importance of educational opportunity in earlier life and recommends health-related behavioural modifications to improve health status in low-educated older adults.

Types of leisure time physical activities (LTPA) of community-dwelling persons who have been screened positive for dementia

Background

To (a) describe the pattern of leisure time physical activities (LTPA) in community-dwelling persons who have been screened positive for dementia and (b) determine the health-related and sociodemographic factors associated with LTPA.

Methods

Data of the general practitioner-based, randomized, controlled intervention trial, DelpHi-MV (Dementia: life- and person-centered help in Mecklenburg-Western Pomerania) were used. Patients aged 70 years or older, who lived at home and had a DemTect< 9 were informed about the study by their General practitioners and invited to participate. Data from 436 participants with complete baseline data were used. Standardized, computer-assisted assessments were made during face-to-face interviews at the participants’ homes.

Results

Two hundred thirty-eight patients (54.6%) carried out LTPA (men 58.4%, women 51.8%). Physically active patients mentioned one to two different activities; diversity of LTPA was higher for men than for women. The most-frequently mentioned types of activity were gardening (35.3%), cycling (24.1%) and mobility training (12.4%); there was only a statistically significant difference between men and women in cycling, χ²(1) = 21.47, p < .001. The odds of LTPA increased with increasing quality of life (OR = 2.41), lower impairments in activities of daily living (OR = 0.85), and living in a rural environment (OR = 2.02).

Conclusions

Our findings suggest that people who have been screened positive for dementia living in a rural area are more likely to be active than people living in an urban area. Following studies should investigate whether this difference has an effect on the progression of dementia.

Trial registration

ClinicalTrial.gov Identifier NCT01401582.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-021-02201-1.