Multi-study coordinated meta-analysis of pulmonary functioning and cognitive ability.

A coordinated multi-study analysis of the longitudinal between cognition and grip strength in aging.

Objectives. Grip strength and cognitive function reflect upper body muscle strength and mental capacities. Cross-sectional research has suggested that in old age these two processes are moderately to highly associated, and that an underlying common cause drives this association. Our aim was to synthesize and evaluate longitudinal research addressing whether changes in grip strength are associated with changes in cognitive function in healthy older adults.

Introduction: This study examines the role of educational attainment, an indicator of cognitive reserve, on transitions in later life between cognitive states (normal Mini-Mental State Examination (MMSE), mild MMSE impairment, and severe MMSE impairment) and death. Methods: Analysis of six international longitudinal studies was performed using a coordinated approach. Multistate survival models were used to estimate the transition patterns via different cognitive states. Life expectancies were estimated.

Objectives: Although personality change is typically considered a symptom of dementia, some studies suggest that personality change may be an early indication of dementia. One prospective study found increases in neuroticism preceding dementia diagnosis. This study extends this research by examining trajectories of personality traits in additional longitudinal studies of aging.

Background: Cognitive reserve was postulated to explain individual differences in susceptibility to ageing, offering apparent protection to those with higher education. We investigated the association between education and change in memory in early old age. 

This study examines the relationship between retirement and cognitive aging. We build on previous research by exploring how different specifications of retirement that reflect diverse pathways out of the labor market, including reason for leaving the pre-retirement job and duration spent in retirement, impact three domains of cognitive functioning. We further assess how early-life factors, including adolescent cognition, and mid-life work experiences, condition these relationships.

Objectives. Given theoretical and methodological advances that propose hypothesis about change in one or multiple processes, analytical methods for longitudinal data have been developed that provide researchers with various options for analyzing change over time. In this paper, we revisited several latent growth curve models that may be considered to answer questions about repeated measures of continuous variables, which may be operationalized as time-varying covariates or outcomes.

Introduction: Although personality change is typically considered a symptom of dementia, some studies suggest that personality change may be an early indication of dementia. This project examines this possibility by examining trajectories of personality traits preceding dementia diagnosis in several longitudinal studies of aging.

Social activity is one aspect of an active lifestyle and some evidence indicates it is related to preserved cognitive function in older adulthood. However, the potential mechanisms underlying this association remain unclear. We investigate 4 potential mediational pathways through which social activity may relate to cognitive performance.

Objectives. The present study examined age differences among older adults in the daily co-occurrence of affect and its potential role in buffering the negative effects of health stressors.

Design. Participants were from the Veterans Affairs Normative Aging Study (NAS) and included 249 young-old adults (age = 60–79 years, M=71.6) and 64 old-old adults (age = 80–89, M = 82.9) who completed questionnaires assessing stressors, physical health symptoms, and positive and negative affect on eight consecutive days.

Background: The DNA methylation-based ‘epigenetic clock’ correlates strongly with chronological age, but it is currently unclear what drives individual differences. We examine cross-sectional and longitudinal associations between the epigenetic clock and four mortality-linked markers of physical and mental fitness: lung function, walking speed, grip strength and cognitive ability.

Research on stress and cognitive aging has primarily focused on examining the effects of biological and psychosocial indicators of stress, with little attention provided to examining the association between perceived stress and cognitive aging. We examined the longitudinal association between global perceived stress (GPS) and cognitive change among 116 older adults (Mage = 80, SD = 6.40, range = 67–96) in a repeated measurement burst design.

We examined the joint contributions of self-reported adverse childhood experiences (ACEs) and recent life events (RLEs) to inflammation at midlife, by testing 3 competing theoretical models: stress generation, stress accumulation, and early life stress sensitization. We aimed to identify potential mediators between adversity and inflammation. Participants were 1,180 middle-aged and older adults from the Midlife in the United States (MIDUS) Biomarker Project (M age = 57.3 years, SD = 11.5; 56% female).

Objective: Older adults are increasingly likely to have two or more chronic medical conditions (multimorbidity) and are consequently at greater risk of disability. Here we examine the role of inflammation in mediating the relationship between multimorbidity and disability. 

Background: Education has been robustly associated with cognitive reserve and dementia, but not with the rate of cognitive aging, resulting in some confusion about the mechanisms of cognitive aging.

Objective: Personality traits predict both health behaviors and mortality risk across the life course. However, there are few investigations that have examined these effects in a single study. Thus, there are limitations in assessing if health behaviors explain why personality predicts health and longevity. Method: Utilizing 14-year mortality data from a national sample of over 6,000 adults from the Midlife in the United States Study, we tested whether alcohol use, smoking behavior, and waist circumference mediated the personality–mortality association.

Background: Previous studies reporting on the interaction between physical activity and genetic susceptibility on obesity have been cross-sectional and have not considered the potential influences of other lifestyle behaviours. The aim of this study was to examine modification of genetic influences on changes across age in adiposity during mid-adulthood by physical activity and smoking.

Early-life cognitive ability is likely to be dynamically related to life course factors including educational attainment, occupational outcomes, health behaviors, activities, health, and subsequent cognitive health. Disentangling the selective and causal processes contributing to cognitive functioning across the life span is challenging and requires long-term investments in longitudinal data.

This commentary on the special section on conscientiousness and healthy aging focuses on several topics brought up in this collection of articles. One is the promise of personality interventions. Despite skepticism on the part of some, such interventions may ultimately prove successful. This is in part because of similarities between personality dimensions and cognitive dimensions and in part due to evidence showing personality is more dynamic and plastic than once believed. The commentary concludes with a discussion of the role of longitudinal investigations to inform interventions.

Objectives. We describe and compare the expected performance trajectories of older adults on the Mini-Mental Status Examination (MMSE) across six independent studies from four countries in the context of a collaborative network of longitudinal studies of aging. A coordinated analysis approach is used to compare patterns of change conditional on sample composition differences related to age, sex, and education. Such coordination accelerates evaluation of particular hypotheses. In particular, we focus on the effect of educational attainment on cognitive decline.

Student service members/veterans represent a growing population on college campuses. Despite this growth, scholarly investigations into their health- and adjustment-related issues are almost nonexistent. The limited research that is available suggests that student service members/veterans may have trouble connecting with their civilian counterparts and be at risk for social isolation.

On average, older people remember less and walk more slowly than do younger persons. Some researchers argue that this is due in part to a common biologic process underlying age-related declines in both physical and cognitive functioning. Only recently have longitudinal data become available for analyzing this claim. We conducted a systematic review of English-language research published between 2000 and 2011 to evaluate the relations between rates of change in physical and cognitive functioning in older cohorts.

The present study used a coordinated analyses approach to examine the association of physical activity and cognitive change in four longitudinal studies. A series of multilevel growth models with physical activity included both as a fixed (between-person) and time-varying (within-person) predictor of four domains of cognitive function (reasoning, memory, fluency, and semantic knowledge) was used. Baseline physical activity predicted fluency, reasoning and memory in two studies.

We illustrate the use of the parallel latent growth curve model using data from OCTO-Twin. We found a significant intercept-intercept and slope-slope association between processing speed and visuospatial ability. Within-person correlations among the occasion-specific residuals were significant, suggesting that the occasion-specific fluctuations around individual’s trajectories, after controlling for intraindividual change, are related between both outcomes.

The current study examines the role of social contact intensity, cognitive activity, and depressive symptoms as within- and between-person mediators for the relationships between physical activity and cognitive functioning. All three types of mediators were considered simultaneously using multilevel structural equations modeling with longitudinal data. The sample consisted of 470 adults ranging from 79.37 to 97.92 years of age (M = 83.4; SD = 3.2) at the first occasion.

The terminal decline hypothesis states that in the proximity of death, an individual’s decline in cognitive abilities accelerates. We aimed at estimating the onset of faster rate of decline in global cognition using Mini Mental State Examination (MMSE) scores from participants of the Cambridge City over 75 Cohort Study (CC75C), a U.K. population-based longitudinal study of aging where almost all participants have died.

Midlife hypertension is associated with increased risk of cognitive impairment in later life. The association between blood pressure (BP) in older ages and cognition is less clear. In this study we provide estimates of between-person and within-person associations of BP and cognition in a population-based sample (N = 382) followed from age 70 across 12 occasions over 30 years. Between-person associations refer to how individual differences in BP relates to individual differences in cognition.

Although the relationship between education and cognitive status is well-known, evidence regarding whether education moderates the trajectory of cognitive change in late life is conflicting. Early studies suggested that higher levels of education attenuate cognitive decline. More recent studies using improved longitudinal methods have not found that education moderates decline. Fewer studies have explored whether education exerts different effects on longitudinal changes within different cognitive domains.

Aging reflects ongoing transactions between context and person across many decades of life. Life course sociology is now central to investigations focused on the dynamic social context of aging, with its distinctive emphasis on long-term patterns in people's statuses, roles, and relationships. Recent advances in the understanding of the genome and its measurement have created new and exciting possibilities for studying the genetic basis of aging-related outcomes.

This chapter contains sections titled: Conceptual Issues at the Interface of Theory, Design, and Analysis, Analytic Approaches for Understanding Within‐Person Change and Variation Methodological Applications in Developmental and Aging Research, Integrative Data Analysis: Within‐Person Change in the Context of Cohort, Country, and Culture, Acknowledgments, References.

Objectives. In this article, we discuss the importance of studying the relationship between health and cognitive function, and some of the methods with which this relationship has been studied.

Joint longitudinal-survival models are useful when repeated measures and event time data are available and possibly associated. The application of this joint model in aging research is relatively rare, albeit particularly useful, when there is the potential for nonrandom dropout. In this article we illustrate the method and discuss some issues that may arise when fitting joint models of this type.

Objective: The terminal cognitive decline hypothesis has been debated for almost 50 years. This hypothesis implies a change in rate of decline within an individual. Therefore, we examine the hypothesis from a within-person perspective using a time to death chronological structure.

Researchers who study human development are interested in how psychological, physiological, and behavioral phenomena change over time in aging individuals. In fact, Baltes and Nesselroade (1979) identified the primary objective of longitudinal developmental research as the “direct identification of intraindividual change” (p. 23). However, this goal is complicated by the possibility that observable change in any given individual may reflect the joint influences of multiple processes.

The study of aging demands an integrative life-span developmental framework, involving interdisciplinary collaborations and multiple methodological approaches for understanding how and why individuals change, in both normative and idiosyncratic ways. We highlight and summarize some of the issues encountered when conducting integrative research for understanding aging-related change, including, the integration of results across different levels of analysis; the integration of theory, design, and analysis; and the synthesis of results across studies of aging.

Replication of research findings across independent longitudinal studies is essential for a cumulative and innovative developmental science. Meta-analysis of longitudinal studies is often limited by the amount of published information on particular research questions, the complexity of longitudinal designs and the sophistication of analyses, and practical limits on full reporting of results. In many cases, cross-study differences in sample composition and measurements impede or lessen the utility of pooled data analysis.

As the authors describe in this chapter, numerous calls have been made for increased collaboration as a means to focus developmental research on within-person processes. The authors highlight and summarize some examples of collaborative and coordinated research, and the authors elaborate on some fundamental ideas for implementing strategies for maximizing our understanding of within person aging-related changes.

Although elevated rates of parent psychosocial distress have been associated with child behavior and emotional problems, little is known about the nature of this relationship over time. This study followed an epidemiological cohort of children and adolescents over 11 years with 4 waves of data collection. Within this cohort, complete data were available on 238 mothers and their children. Behavior and emotional problems were assessed using the DBC, maternal mental health with the GHQ. Multivariate growth curve modelling was used to evaluate the commonality of individual change patterns.