Patterns and associates of cognitive function, psychosocial wellbeing and health in the Lothian Birth Cohort 1936

Investigation of memory-enhancing effects of Streptococcus thermophilus EG007 in mice and elucidating molecular and metagenomic characteristics using nanopore sequencing

Over the past decades, accumulating evidences have highlighted the gut microbiota as a key player in the brain functioning via microbiota–gut–brain axis, and accordingly, the beneficial role of several probiotic strains in cognitive ability also have been actively investigated. However, the majority of the research have demonstrated the effects against age-related cognitive decline or neurological disease. To this end, we aimed to investigate lactic acid bacteria strains having beneficial effects on the cognitive function of healthy young mice and elucidate underlying characteristics by carrying out nanopore sequencing-based genomics and metagenomics analysis. 8-week consumption of Streptococcus thermophilus EG007 demonstrated marked enhancements in behavior tests assessing short-term spatial and non-spatial learning and memory. It was revealed that EG007 possessed genes encoding various metabolites beneficial for a health condition in many aspects, including gamma-aminobutyric acid producing system, a neurotransmitter associated with mood and stress response. Also, by utilizing 16S–23S rRNA operon as a taxonomic marker, we identified more accurate species-level compositional changes in gut microbiota, which was increase of certain species, previously reported to have associations with mental health or down-regulation of inflammation or infection-related species. Moreover, correlation analysis revealed that the EG007-mediated altered microbiota had a significant correlation with the memory traits.

Dynamic Longitudinal Associations Between Social Support and Cognitive Function: A Prospective Investigation of the Directionality of Associations

Objective

To investigate the reciprocity of social support and cognitive function in late life.

Method

Analyses were based on three parallel repeat measures of social support and cognition from the Whitehall II cohort, providing 10-year follow-up of 6,863 participants (mean age 55.8 years, SD 6.0 at baseline). Alternative hypotheses were evaluated via four bivariate dual change score models: Full coupling model estimated mutual influences of social support and cognition on subsequent changes in each other; social causation model assumed a unidirectional influence from social support onto changes in cognition, while the opposite assumption was tested by health selection model; last, no coupling model suggested independent growth of these two sets of variables.

Results

A better cognition at the preceding stage was related to less positive changes in confiding support and less negative changes in practical support. In contrast, influences from social support on subsequent changes in cognition were not detected.

Discussion

This empirical study provides some evidence for the health selection mechanism, such that cognition modified changes in social support. The hypothesized neuroprotective effect of social support was not detectable.

Identification of Heterogeneous Cognitive Subgroups in Community-Dwelling Older Adults: A Latent Class Analysis of the Einstein Aging Study

OBJECTIVES

The aim of this study was to identify natural subgroups of older adults based on cognitive performance, and to establish each subgroup's characteristics based on demographic factors, physical function, psychosocial well-being, and comorbidity.

METHODS

We applied latent class (LC) modeling to identify subgroups in baseline assessments of 1345 Einstein Aging Study (EAS) participants free of dementia. The EAS is a community-dwelling cohort study of 70+ year-old adults living in the Bronx, NY. We used 10 neurocognitive tests and 3 covariates (age, sex, education) to identify latent subgroups. We used goodness-of-fit statistics to identify the optimal class solution and assess model adequacy. We also validated our model using two-fold split-half cross-validation.

RESULTS

The sample had a mean age of 78.0 (SD=5.4) and a mean of 13.6 years of education (SD=3.5). A 9-class solution based on cognitive performance at baseline was the best-fitting model. We characterized the 9 identified classes as (i) disadvantaged, (ii) poor language, (iii) poor episodic memory and fluency, (iv) poor processing speed and executive function, (v) low average, (vi) high average, (vii) average, (viii) poor executive and poor working memory, (ix) elite. The cross validation indicated stable class assignment with the exception of the average and high average classes.

CONCLUSIONS

LC modeling in a community sample of older adults revealed 9 cognitive subgroups. Assignment of subgroups was reliable and associated with external validators. Future work will test the predictive validity of these groups for outcomes such as Alzheimer's disease, vascular dementia and death, as well as markers of biological pathways that contribute to cognitive decline. (JINS, 2018, 24, 511-523).

Healthy cognitive ageing in the Lothian Birth Cohort studies: marginal gains not magic bullet

In the face of shifting demographics and an increase in human longevity, it is important to examine carefully what is known about cognitive ageing, and to identify and promote possibly malleable lifestyle and health-related factors that might mitigate age-associated cognitive decline. The Lothian Birth Cohorts of 1921 (LBC1921, n = 550) and 1936 (LBC1936, n = 1091) are longitudinal studies of cognitive and brain ageing based in Scotland. Childhood IQ data are available for these participants, who were recruited in later life and then followed up regularly. This overview summarises some of the main LBC findings to date, illustrating the possible genetic and environmental contributions to cognitive function (level and change) and brain imaging biomarkers in later life. Key associations include genetic variation, health and fitness, psychosocial and lifestyle factors, and aspects of the brain's structure. It addresses some key methodological issues such as confounding by early-life intelligence and social factors and emphasises areas requiring further investigation. Overall, the findings that have emerged from the LBC studies highlight that there are multiple correlates of cognitive ability level in later life, many of which have small effects, that there are as yet few reliable predictors of cognitive change, and that not all of the correlates have independent additive associations. The concept of marginal gains, whereby there might be a cumulative effect of small incremental improvements across a wide range of lifestyle and health-related factors, may offer a useful way to think about and promote a multivariate recipe for healthy cognitive and brain ageing.

Adapting to Aging: Older People Talk About Their Use of Selection, Optimization, and Compensation to Maximize Well-being in the Context of Physical Decline

Objectives:

Selection, Optimization, and Compensation (SOC) may contribute to successful aging by helping older people maximize well-being in the context of physical decline. To explore this hypothesis, and to investigate the potential for narrative analysis to improve understanding of SOC, we analyze interviews conducted with 15 members of the 6-Day Sample, a cohort of Scots born in 1936.

Method:

Interviewees were chosen based on their physical function and well-being scores. Interviews were analyzed to investigate “SOC talk,” that is, older people’s talk about SOC behaviors in everyday life. Types and amounts of SOC talk were quantified, and talk was narratively analyzed. We hypothesized that older people who engaged in more SOC talk would have higher well-being.

Results:

Older people who engaged in high levels of SOC talk had high well-being despite low physical function. Those who engaged in little SOC talk had low well-being despite higher physical function.

Discussion:

The concept of successful aging is valuable in part because of its narrative quality: One must strive to keep one’s life story developing despite physical decline and other losses. We provide evidence, from the perspectives of older people themselves, of the ways in which SOC may play a role in that process.

Life review in advanced age: qualitative research on the 'start in life' of 90-year-olds in the Lothian Birth Cohort 1921

Background

This research report presents findings on ‘start in life’ from a qualitative study of 90-year-olds from the Lothian Birth Cohort 1921. The study aimed to contextualise the LBC1921 cohort in time and place, describe cohort members’ experiences of family and schooling and stimulate further inquiry into the relationships between ‘start in life’ and risk and resilience factors relating to longevity and healthy ageing. Scottish education and family life in the early 1930s are briefly described.

Methods

Life review questionnaire: A qualitative Life Review Questionnaire was developed, requiring free-text handwritten responses. Its ‘Start in Life’ section focused on schooling and family support.

Sample: Wave 4 of the Lothian Birth Cohort 1921 involved testing 129 members near to their 90^th birthday. They reside largely in Edinburgh and its environs. The Life Review Questionnaire was administered to 126 participants, 54 % women.

Qualitative analysis: Thematic analysis was the qualitative technique used to categorise, code and extract meaning from questionnaire text. Narratives were extracted from the data to present illustrative stories.

Results

Narratives of start in life gave contextual description. Thematic analysis showed LBC1921 members enjoying their schooling, highlighting teachers, academic achievement, school activities and school friendships. Personal qualities, family circumstances and aspects of schooling sometimes hindered educational performance. Family life was recalled mostly with warmth and parents were often portrayed as valuing education and supporting learning and development. Family adversity from poverty, parental illness and parental death was often mitigated by support from parents (or the remaining parent). Overall, most cohort members believed that they had got off to a good ‘start in life’.

Conclusions

This qualitative investigation of ‘start in life’ adds context and richness to quantitative investigations of the sizeable LBC1921 cohort, stimulating fresh insights and hypotheses into the relationship between child risk and resilience factors that may influence ageing. It demonstrates the utility and wider application of the Life Review Questionnaire. Although the surviving cohort is not representative of their childhood peers, their words provide insight into the processes of weaving experience and memory into a rich texture of meanings that may help create wellbeing across a lifetime.