Does Rural Living in Early Life Increase the Risk for Reduced Cognitive Functioning in Later Life?

Health Disparities in Appalachian and Other Rural Communities

Rural areas are home to a larger proportion of older adults and populations who age within these locales and suffer disproportionately from health, mental health, and economic disparities compared to their urban counterparts. This article will explore the disparities faced by persons that reside in rural communities across the lifespan. It will briefly discuss what is meant by rural. As a rural region at specific risk, the issues confronting those aging in Appalachia will be examined. Finally, best practices and future directions to combat health disparities among rural residents and elders will be discussed. This includes the Appalachian Gerontology Experiences: Advancing Diversity in Aging Research training program which recruits and trains minority and first-generation undergraduate students in aging and health disparity research.

An investigation of psychoactive polypharmacy and related gender-differences in older adults with dementia: a retrospective cohort study

BACKGROUND

Older adults living with dementia may express challenging responsive behaviours. One management strategy is pharmacologic treatment though these options often have limited benefit, which may lead to multiple treatments being prescribed.

METHODS

The aim of the present study was to describe psychoactive medication polypharmacy and explore factors associated with psychoactive polypharmacy in a cohort of older adults living with dementia in Nova Scotia, Canada, including a gender-stratified analysis. This was a retrospective cohort study of those aged 65 years or older with a recorded diagnosis of dementia between 2005 and 2015. Medication dispensation data was collected from April 1, 2010, or dementia diagnosis (cohort entry) to either death or March 31, 2015 (cohort exit). Psychoactive medication claims were captured. Psychoactive medication polypharmacy was defined as presence of three or more psychoactive prescription medications dispensed to one subject and overlapping for more than 30 days. Psychoactive polypharmacy episodes were described in duration, quantity, and implicated medications. Regression analysis examined factors associated with experience and frequency of psychoactive polypharmacy. All analysis were stratified by gender.

RESULTS

The cohort included 15,819 adults living with dementia (mean age 80.7 years; 70.0% female), with 99.4% (n = 15,728) receiving at least one psychoactive medication over the period of follow-up. Psychoactive polypharmacy was present in 19.3% of the cohort. The gender specific logistic regressions demonstrated that for both men and women a younger age was associated with an increased risk of psychoactive polypharmacy (women: OR 0.97, 95%CI[0.96, 0.98], men: OR 0.96, 95%CI[0.95, 0.97]). Men were less likely to experience psychoactive polypharmacy if their location of residence was urban (OR 0.86, 95%CI[0.74, 0.99]). There was no significant association between location of residence (urban or rural) and psychoactive polypharmacy for women living with dementia. Antidepressants were the most dispensed medication class, while quetiapine was the most dispensed medication.

CONCLUSIONS

This study suggests that of adults living with dementia those of younger ages were more likely to experience psychoactive polypharmacy and that men living with dementia in rural locations may benefit from increased access to non-pharmacological options for dementia management.

Residential trajectories across the life course and their association with cognitive functioning in later life

Previous work has found that later life urban-rural differences in cognitive health can be largely explained by indicators of cognitive reserve such as education or occupation. However, previous research concentrated on residence in limited, specific, periods. This study offers a detailed investigation on the association between urban (vs. rural) residence from birth, and cognitive functioning in older age. Using data from the Survey of Health Ageing and Retirement in Europe we created residential trajectories from birth to survey enrolment with a combination of sequence and cluster analysis. Using mixed-effects models, we investigated the association between residential trajectories in early, mid, and later life and three cognitive functioning outcomes: immediate recall, delayed recall, and verbal fluency. In a sample of 38,165 participants, we found that, even after accounting for differences related to education and occupation, rural (vs. urban) residence in early life remained associated with poorer cognitive performance later in life. This suggests that growing up in rural regions leads to a long-term disadvantage in cognitive functioning. Thus, public health policies should consider that urban-rural inequalities in early life may have long-lasting associations with inequalities in cognitive health in old and very old age.

Are Brain and Cognitive Reserve Shaped by Early Life Circumstances?

When growing older, many people are faced with cognitive deterioration, which may even amount to a form of dementia at some point in time. Although neuropathological signs of dementia disorders can often be demonstrated in brains of patients, the degree to which clinical symptoms are present does mostly not accurately reflect the amount of neuropathology that is present. Sometimes existent pathology even goes without any obvious clinical presentation. An explanation for this phenomenon may be found in the concept of reserve capacity. Reserve capacity refers to the ability of the brain to effectively buffer changes that are associated with normal aging processes and to cope with pathological damage. A larger reserve capacity has been suggested to increase resilience against age-associated cognitive deterioration and dementia disorders. Traditionally, a division has been made between brain reserve, which is based on morphological characteristics of the brain, and cognitive reserve, which is based on functional characteristics of the brain. The present review discusses the premises that brain and cognitive reserve capacity are shaped by prenatal and early postnatal factors. Evidence is accumulating that circumstances during the first 1,000 days of life are of the utmost importance for the lifelong health of an individual. Cognitive deterioration and dementia disorders may also have their origin in early life and a potentially important pathway by which the early environment affects the risk for neurodegenerative diseases is by developmental programming of the reserve capacity of the brain. The basic idea behind developmental programming of brain and cognitive reserve is explained and an overview of studies that support this idea is presented. The review is concluded by a discussion of potential mechanisms, synthesis of the evidence and relevance and future directions in the field of developmental origins of reserve capacity.

Life course linkages between enriching early-life activities and later life cognition: Evidence from the Wisconsin Longitudinal Study

Prior research suggests that participation in enriching early-life activities (EELAs) has long-term benefits for cognitive health and aging. This study aims to examine the life course processes underlying these associations by drawing on theoretical models from life course epidemiology. Specifically, we tested sensitive-period effects, social pathways, and selection effects as potential explanations for linkages between greater participation in EELAs and better later life cognition. We drew on data from the Wisconsin Longitudinal Study (WLS), which is among the longest-running cohort studies in the U.S. that has followed graduates (all identified as non-Hispanic White) from Wisconsin high schools since 1957. We used prospective measures of key variables, including information from high school yearbooks, with assessments of cognitive performance at ages 65 and 72. Results from multilevel modeling indicated that greater participation in cognitively oriented extracurricular activities (but not physically nor socially oriented activities) was associated with both better language/executive functioning and memory at age 65. Although the size of these associations was reduced when accounting for other cognitive resources in adolescence (childhood socioeconomic status and adolescent cognitive ability) and in midlife (adult socioeconomic status and formal group participation), there remained small, yet statistically robust, associations. We did not find robust associations between greater EELA engagement and slower rates of decline in cognition between ages 65 and 72, nor did we find evidence of gender differences. Results suggest that for this cohort of older adults, EELA participation is part of life course "protective chains," whereby exposures to assets at one point in the life course increase the likelihood of subsequent exposures, each sequentially and in their own right, toward better later life cognition. We discuss how results support the importance of policies and practices to promote healthy cognitive development among youth for the long-term cognitive health of a rapidly aging U.S. population.

Early Life Interventions Can Shape Aging

It is well documented that the environment of the developing fetus, including availability of nutrients and presence of toxins, can have major impact on adult phenotype, age-related traits and risk of chronic disease. There is also accumulating evidence that postnatal environment can impact adult characteristics related to evolutionary fitness, health, and aging. To determine whether early life hormonal interventions can alter trajectory of aging, we have examined the effects of early life growth hormone (GH) replacement therapy in Prop1^df (Ames dwarf) mice which are GH deficient and remarkably long lived. Twice-daily GH injections between the ages of two and eight weeks completely normalized ("rescued") a number of adult metabolic characteristics believed to contribute to extended longevity of these mutants. Importantly, longevity of Ames dwarf mice was reduced by early life GH treatment. This was associated with histone H3 modifications. We conclude that the trajectory of mammalian aging can be modified by early life interventions. Mechanistic links among interventions during postnatal development, adult metabolic characteristics, aging, and longevity, apparently involve epigenetic phenomena.