Changing Minds: A Study of Cognitive Change Disparities and Their Social Determinants Among Older Adults in the Health and Retirement Study, 1998-2012

Open Access
Author:
Sherman-Wilkins, Kyler James
Graduate Program:
Sociology
Degree:
Doctor of Philosophy
Document Type:
Dissertation
Date of Defense:
May 12, 2017
Committee Members:
  • David R. Johnson , Dissertation Advisor
  • David R. Johnson, Committee Chair
  • Steven Andrew Haas, Committee Member
  • Liying Luo, Committee Member
  • Rhonda Belue, Outside Member
Keywords:
  • Cognitive Decline
  • Intersectionality
  • Life Course
  • General Growth Mixture Models
  • Disparities in Aging
Abstract:
Despite the rapidly growing literature on cognitive functioning trajectories, sociologists and social demographers have been largely removed from the research on age-related cognitive change. Indeed, research on cognitive decline tends to be dominated by biological psychologists and cognitive neuroscientists. Given the important insights that the sociological and demographic perspective can provide to understanding cognitive aging processes—particularly with regards to the social determinants of cognitive aging and how the patterns of change vary across social locations (e.g. race, gender, socioeconomic status)—it is imperative for a social demographic analysis to be applied when examining cognitive aging. This dissertation aims to describe and explain sociodemographic variations in trajectories of age-related cognitive decline. Using data from the nationally representative longitudinal Health and Retirement Study (HRS) and drawing on the life course perspective, reserve theory, intersectionality theory, and differential exposure/susceptibility perspectives, this study uses an integrated person-centered/variable-centered methodological approach to examine both patterns of cognitive decline across social locations as well as said patterns’ social determinants. Broadly, this study has three main aims. First, this study aims to provide a more nuanced understanding of the various trajectories of age-related cognitive decline by estimating and examining distinct classes of cognitive aging trajectories using general growth mixture modeling with latent trajectory classes (GGMM-LTC). Further, this study seeks to ascertain whether the cognitive aging disparities follow an age-as-leveler, persistent inequality, or cumulative (dis)advantage pattern. Additionally, I examine whether active or passive reserve processes underlie changes in cognitive performance with advancing age. Building on the previous identification of distinct classes of cognitive decline, the second aim of this study is to examine patterns of cognitive aging across social locations by applying intersectionality theory. Lastly, the third aim is to employ differential exposure and differential susceptibility hypotheses to explain racial and gender differences in cognitive aging patterns. Findings addressing the first aim indicate that distinct classes for both episodic memory and mental status exist, and that membership in classes is stratified by race, gender, socioeconomic status, health, and early life adversity. Additionally, support for the age-as leveler, persistent inequality, and cumulative (dis)advantage patterns were found depending on the groups compared and the cognitive domain examined. It was also found that the cognitive reserve process plays out in the mental status domain. Findings related to the second aim of this study indicate that gender and levels of education influence cognitive trajectory class membership for blacks and whites in both episodic memory and mental status domains. More specifically, whites and respondents with higher levels of education are more likely to belong in episodic memory and mental status classes with higher levels of initial functioning. Further, I find evidence for the multiplicative effects of gender and education for episodic memory among whites and for mental status among both whites and blacks thus providing support for the intersectionality perspective. Lastly, findings related to the third aim show that race and gender are both significant predictors of episodic memory and mental status trajectory class membership. Blacks and men are more likely to belong in episodic memory trajectory classes characterized by low initial function with more rapid declines than their white and female counterparts. For mental status, blacks and women are more likely to be in lower initial functioning classes, but are advantaged with regards to rate of decline. Additionally, findings provide little evidence for the notion that early life adversity attenuates the relationship between race and/or gender and cognitive decline trajectory class membership, thereby no support for the differential exposure hypothesis was found. Lastly, lack of statistically significant interactions between both race and gender and early life adversity indicates that there is no support for the differential susceptibility hypothesis. Overall, findings herein show that the social patterning and determinants of cognitive decline in the U.S. are complex, varying with the groups being compared as well as the cognitive domain in question. Moreover, this dissertation provides an argument that researchers in the area of cognitive decline would benefit greatly from an intersectionality approach. This dissertation concludes with the placement of current findings within the existing literature, a detailing of policy implications, a discussion of study limitations, and the outlining of planned future research in the area of cognitive decline and ideas for better cognitive functioning assessment in the population.