Estimation and Sensitivity Analysis for Causal Decomposition in Heath Disparity Research

In the field of disparities research, there has been growing interest in developing a counterfactual-based decomposition analysis to identify underlying mediating mechanisms that help reduce disparities in populations. Despite rapid development in the area, most prior studies have been limited to regression-based methods, undermining the possibility of addressing complex models with multiple mediators and/or heterogeneous effects. We propose an estimation method that effectively addresses complex models. Moreover, we develop a novel sensitivity analysis for possible violations of identification assumptions. The proposed method and sensitivity analysis are demonstrated with data from the Midlife Development in the US study to investigate the degree to which disparities in cardiovascular health at the intersection of race and gender would be reduced if the distributions of education and perceived discrimination were the same across intersectional groups

Gender differences in the pathways from childhood disadvantage to metabolic syndrome in adulthood: An examination of health lifestyles.

We investigate whether socioeconomic status (SES) in childhood shapes adult health lifestyles in domains of physical activity (leisure, work, chores) and diet (servings of healthy [i.e., nutrient-dense] vs. unhealthy [energy-dense] foods). Physical activity and food choices vary by gender and are key factors in the development of metabolic syndrome (MetS). Thus, we examined gender differences in the intervening role of these behaviors in linking early-life SES and MetS in adulthood. We used survey data (n = 1054) from two waves of the Midlife in the U.S. Study (MIDUS 1 and 2) and biomarker data collected at MIDUS 2. Results show that individuals who were disadvantaged in early life are more likely to participate in physical activity related to work or chores, but less likely to participate in leisure-time physical activity, the domain most consistently linked with health benefits. Women from low SES families were exceedingly less likely to complete recommended amounts of physical activity through leisure. Men from low SES consumed more servings of unhealthy foods and fewer servings of healthy foods. The observed associations between childhood SES and health lifestyles in adulthood persist even after controlling for adult SES. For men, lack of leisure-time physical activity and unhealthy food consumption largely explained the association between early-life disadvantage and MetS. For women, leisure-time physical activity partially accounted for the association, with the direct effect of childhood SES remaining significant. Evidence that material deprivation in early life compromises metabolic health in adulthood calls for policy attention to improve economic conditions for disadvantaged families with young children where behavioral pathways (including gender differences therein) may be shaped. The findings also underscore the need to develop gender-specific interventions in adulthood

The importance of examining movements within the US health care system: sequential logit modeling

Background: Utilization of specialty care may not be a discrete, isolated behavior but rather, a behavior of sequential movements within the health care system. Although patients may often visit their primary care physician and receive a referral before utilizing specialty care, prior studies have underestimated the importance of accounting for these sequential movements. Methods: The sample included 6,772 adults aged 18 years and older who participated in the 2001 Survey on Disparities in Quality of Care, sponsored by the Commonwealth Fund. A sequential logit model was used to account for movement in all stages of utilization: use of any health services (i.e., first stage), having a perceived need for specialty care (i.e., second stage), and utilization of specialty care (i.e., third stage). In the sequential logit model, all stages are nested within the previous stage. Results: Gender, race/ethnicity, education and poor health had significant explanatory effects with regard to use of any health services and having a perceived need for specialty care, however racial/ethnic, gender, and educational disparities were not present in utilization of specialty care. After controlling for use of any health services and having a perceived need for specialty care, inability to pay for specialty care via income (AOR = 1.334, CI = 1.10 to 1.62) or health insurance (unstable insurance: AOR = 0.26, CI = 0.14 to 0.48; no insurance: AOR = 0.12, CI = 0.07 to 0.20) were significant barriers to utilization of specialty care. Conclusions: Use of a sequential logit model to examine utilization of specialty care resulted in a detailed representation of utilization behaviors and patient characteristics that impact these behaviors at all stages within the health care system. After controlling for sequential movements within the health care system, the biggest barrier to utilizing specialty care is the inability to pay, while racial, gender, and educational disparities diminish to non-significance. Findings from this study represent how Americans use the health care system and more precisely reveals the disparities and inequalities in the U.S. health care system

Adult Children’s Education and Physiological Dysregulation Among Older Parents

ObjectivesDespite growing awareness that children's education benefits the health of older parents, the underlying mechanisms of this relationship are not well-understood. We investigated (a) the associations between children's education and biological functioning of parents, (b) psychosocial and behavioral factors that explain the associations, and (c) gendered patterns in the associations.MethodsUsing longitudinal data from a nationally representative sample of older Taiwanese, we performed mediation analysis of the association between adult children's education and physiological dysregulation of their parents.ResultsOffspring's schooling is inversely associated with parental inflammation after controlling for parental socioeconomic status and baseline health. Parents who have well-educated children report higher social standing and life satisfaction, experience fewer stressful events, and are more likely to engage in healthy behaviors related to smoking and diet. These factors moderately attenuate the associations between children's education and parental inflammation. There is no conclusive evidence that mothers and fathers benefit differently from having well-educated children.DiscussionParents who devote family and personal resources to their offspring's schooling may have better biological profiles in later life. Well-educated children may promote their parents' wellbeing by strengthening perceived social status, reducing exposure to stressors, and encouraging a healthy lifestyle

Childhood abuse and physiological dysregulation in midlife and old age

The overarching goal of my research is to incorporate sociological perspectives (the life course perspective, inequality theory) with biomedical knowledge (stress theory) to document midlife and old age health for victims of childhood abuse. Using data from the National Survey of Midlife Development in the U.S. (MIDUS), I explore the extent to which childhood abuse creates physiological dysregulation and chronic diseases: cortisol abnormality (Chapter 2), metabolic syndrome (MetS) (Chapter 3), elevated markers of inflammation (Chapter 4), and three immune-related disorders (asthma, allergies, arthritis) (Chapter 2). I then explore the extent to which these associations are explained by three potential mediators: behavioral risk factors (sleeping and eating problems, body mass index [BMI]), perceived stress, and social relationship quality (Chapters 3-4). I also investigate whether profiles of childhood abuse and the pathways linking abuse to MetS differ by gender (Chapter 3). Finally, I assess whether the effects of childhood abuse on inflammatory markers vary by age group (Chapter 4). I find five distinct classes of childhood abuse for the full sample and for women and four for men. Women are more likely than men to report frequent emotional and sexual abuse. Childhood abuse is associated with low cortisol levels and immune-related disorders. Low levels of cortisol partially mediate the association between abuse and both allergies and arthritis. Some abuse subgroups are at greater risk of MetS than the no abuse subgroup. For women, frequent sexual abuse increases the risk of MetS; this association is not statistically significant among men. The associations between abuse and inflammatory markers vary by age. In the younger age groups (ages 34-44 and 45-54), the levels of inflammatory markers for victims are higher than non-victims; there are no statistically significant differences in the older age groups (ages 55-64 and 65-84). Victims are at greater risk of mortality, suggesting that selective mortality might contribute to the reduced gap in the older age cohorts. High BMI, sleep problems, and weak or strained family ties partially mediate the association. Overall, my project demonstrates how integrating sociological perspectives and biomedical knowledge illuminates the associations between early life adversity and lifelong health consequences.Ph. D.Includes bibliographical referencesIncludes vitaby Chioun Le