The Mediating Role of Systemic Inflammation and Moderating Role of Race/Ethnicity in Racialized Disparities in Incident Dementia: A Decomposition Analysis.

Background: Exposure to systemic racism is linked to increased dementia burden. To assess systemic inflammation as a potential pathway linking exposure to racism and dementia disparities, we investigated the mediating role of C-reactive protein (CRP), a systemic inflammation marker, and the moderating role of race/ethnicity on racialized disparities in incident dementia. Methods: In the US Health and Retirement Study (n=5,143), serum CRP was measured at baseline (2006, 2008 waves). Incident dementia was classified by cognitive tests over a six-year follow-up. Self-reported racialized categories were a proxy for exposure to the racialization process. We decomposed racialized disparities in dementia incidence (non-Hispanic Black and/or Hispanic vs. non-Hispanic White) into 1) the mediated effect of CRP, 2) the moderated portion attributable to the interaction between racialized group membership and CRP, and 3) the controlled direct effect (other pathways through which racism operates). Results: The 6-year cumulative incidence of dementia was 15.5%. Among minoritized participants (i.e., non-Hispanic Black and/or Hispanic), high CRP levels (> 75th percentile or 4.57µg/mL) was associated with 1.27 (95%CI: 1.01,1.59) times greater risk of incident dementia than low CRP (≤4.57µg/mL). Decomposition analysis comparing minoritized versus non-Hispanic White participants showed that the mediating effect of CRP accounted for 2% (95% CI: 0%, 6%) of the racial disparity, while the interaction effect between minoritized group status and high CRP accounted for 12% (95% CI: 2%, 22%) of the disparity. Findings were robust to potential violations of causal mediation assumptions. Conclusions: Systemic inflammation mediates racialized disparities in incident dementia.

Linking History to Contemporary State-Sanctioned Slow Violence through Cultural and Structural Racism.

Environmental scientists started documenting the racial inequities of environmental exposures (e.g., proximity to waste facilities or to industrial pollution) in the 1970s and 1980s. Since then, research has documented inequities in exposures to nearly every studied environmental hazard, showing that American society delivers racial violence toward non-White families. Through cultural racism, a resilient social hierarchy is set where the lives of some groups of people are considered more valuable than others; then, through structural racism, institutions unequally mete and dole environmental benefits and burdens to these groups. We argue that the "slow violence" of environmental racism is linked to other forms of racial violence that have been enacted throughout history. We discuss the meaning of cultural racism as it pertains to the hierarchy of groups of people whose lives are valued unequally and its link to structural racism. To remedy this environmental racial violence, we propose shifts in the empirical research on environmental inequities that are built upon, either implicitly or explicitly, the interconnected concepts of cultural and structural racism that link historical to contemporary forms of racial violence.

Structural Racism: The Rules and Relations of Inequity.

Why do racial inequalities endure despite numerous attempts to expand civil rights in certain sectors? A major reason for this endurance is due to lack of attention to structural racism. Although structural and institutional racism are often conflated, they are not the same. Herein, we provide an analogy of a "bucky ball" (Buckminsterfullerene) to distinguish the two concepts. Structural racism is a system of interconnected institutions that operates with a set of racialized rules that maintain White supremacy. These connections and rules allow racism to reinvent itself into new forms and persist, despite civil rights interventions directed at specific institutions. To illustrate these ideas, we provide examples from the fields of environmental justice, criminal justice, and medicine. Racial inequities in power and health will persist until we redirect our gaze away from specific institutions (and specific individuals), and instead focus on the resilient connections among institutions and their racialized rules.

Life course trauma and muscle weakness in older adults by gender and race/ethnicity: Results from the U.S. health and Retirement Study.

Muscle weakness, as measured by handgrip strength, is a primary determinant of physical functioning and disability. There is a high burden of muscle weakness in the United States with close to 50 percent of older Americans meeting criteria for clinical muscle weakness. While previous racial/ethnic disparities have been documented among older adults, the extent to which lifecourse trauma shapes muscle strength trajectories is unknown. Using U.S. Health and Retirement Study (N = 20,472, Mean Age = 63.8 years) data on grip strength (2006-2014, up to 3 assessments) and retrospectively reported traumatic events, we fit gender-stratified growth curve models to investigate whether traumatic events experienced across the lifecourse or at distinct sensitive periods (childhood, early/emerging adulthood or mid-life) predicted later-life trajectories of grip strength. There was no association between cumulative trauma and trajectories of grip strength and the main effects for the life stage models were largely null. However, among White women, our results suggest that traumatic events experienced during childhood (ß = -0.012; 95% CI = -0.024, 0.0004) compared to middle adulthood are associated with faster declines in grip strength in later life. Traumatic events reported during childhood was related to a slower decline in grip strength over time among Hispanic women compared to that for White women (ß = 0.086, 95% CI = 0.044, 0.128). Among Black men, the association between traumatic events during early/emerging adulthood and age-related declines in grip strength was stronger for Black men than for White men (interaction ß = -0.070; 95% CI = -0.138, 0.001). Traumatic events experienced during distinct life stages may influence later life declines in grip strength and exacerbate racial inequalities in later life. This study addresses an important gap by investigating the life course social determinants of later life muscle strength, which is a key driver of physical functioning and mobility.

Understanding the intersection of race and place: the case of tuberculosis in Michigan.

BACKGROUND: Race and place intersect to produce location-based variation in disease distributions. We analyzed the geographic distribution of tuberculosis (TB) incidence in Michigan, USA to better understand the complex interplay between race and place, comparing patterns in Detroit, Wayne County and the state of Michigan as a whole. METHODS: Using cross-sectional TB surveillance data from the Michigan Department of Health and Human Services, multivariable statistical models were developed to analyze the residence patterns of TB incidence from 2007 through 2012. Two-way interactions among the residence location and race of cases were assessed. RESULTS: Overall, Detroit residents experienced 58% greater TB incidence than residents of Wayne County or the state of Michigan. Racial inequalities were less pronounced in Detroit compared to both Wayne County and the state of Michigan. Blacks in Detroit had 2.01 times greater TB incidence than Whites, while this inequality was 3.62 times more in Wayne County and 8.72 greater in the state of Michigan. CONCLUSION: Our results highlight how race and place interact to influence patterns of TB disease, and the ways in which this interaction is context dependent. TB elimination in the U.S. will require strategies that address the local social environment, as much as the physical environment.

Interpreting Subjective and Objective Measures of Job Resources: The Importance of Sociodemographic Context.

Salutary retirement policy depends on a clear understanding of factors in the workplace that contribute to work ability at older ages. Research in occupational health typically uses either self-reported or objective ratings of the work environment to assess workplace determinants of health and work ability. This study assessed whether individual characteristics and work-related demands were differentially associated with (1) self-reported ratings of job resources from older workers in the Health and Retirement Study, and (2) corresponding objective ratings of job resources from the Occupational Information Network (O*NET). Results from regression and relative weights analyses showed that self-reported ratings were associated with self-reported job demands and personal resources, whereas corresponding O*NET ratings were associated with differences in gender, race, or socioeconomic standing. As a result, subjective ratings may not capture important aspects of aging workers' sociodemographic background that influence work ability, occupational sorting, opportunities for advancement, and ultimately the job resources available to them. Future studies should consider including both subjective and objective measures to capture individual and societal level processes that drive the relationship between work, health, and aging.

Neighbourhood racial/ethnic residential segregation and cardiometabolic risk: the multiethnic study of atherosclerosis.

BACKGROUND: Racial residential segregation has been linked to adverse health outcomes, but associations may operate through multiple pathways. Prior studies have not examined associations of neighbourhood-level racial segregation with an index of cardiometabolic risk (CMR) and whether associations differ by race/ethnicity. METHODS: We used data from the Multi-Ethnic Study of Atherosclerosis to estimate cross-sectional and longitudinal associations of baseline neighbourhood-level racial residential segregation with a composite measure of CMR. Participants included 5015 non-Hispanic black, non-Hispanic white and Hispanic participants aged 45-84 years old over 12 years of follow-up (2000-2012). We used linear mixed effects models to estimate race-stratified associations of own-group segregation with CMR at baseline and with the rate of annual change in CMR. Models were adjusted for sociodemographics, medication use and individual-level and neighbourhood-level socioeconomic status (SES). RESULTS: In models adjusted for sociodemographics and medication use, high baseline segregation was associated with higher baseline CMR among blacks and Hispanics but lower baseline CMR among whites. Individual and neighbourhood-level SES fully explained observed associations between segregation and CMR for whites and Hispanics. However, associations of segregation with CMR among blacks remained (high vs low segregation: mean difference 0.17 SD units, 95% CI 0.02 to 0.32; medium vs low segregation: mean difference 0.18 SD units, 95% CI 0.03 to 0.33). Baseline segregation was not associated with change in CMR index scores over time. CONCLUSION: Associations of own-group racial residential segregation with CMR varied by race/ethnicity. After accounting for SES, living in a more segregated neighbourhood was associated with greater risk among black participants only.

The weight of racism: Vigilance and racial inequalities in weight-related measures.

In the United States, racial/ethnic inequalities in obesity are well-documented, particularly among women. Using the Chicago Community Adult Health Study, a probability-based sample in 2001-2003 (N = 3105), we examined the roles of discrimination and vigilance in racial inequalities in two weight-related measures, body mass index (BMI) and waist circumference (WC), viewed through a cultural racism lens. Cultural racism creates a social environment in which Black Americans bear the stigma burden of their racial group while White Americans are allowed to view themselves as individuals. We propose that in this context, interpersonal discrimination holds a different meaning for Blacks and Whites, while vigilance captures the coping style for Blacks who carry the stigma burden of the racial group. By placing discrimination and vigilance within the context of cultural racism, we operationalize existing survey measures and utilize statistical models to clarify the ambiguous associations between discrimination and weight-related inequalities in the extant literature. Multivariate models were estimated for BMI and WC separately and were stratified by gender. Black women had higher mean BMI and WC than any other group, as well as highest levels of vigilance. White women did not show an association between vigilance and WC but did show a strong positive association between discrimination and WC. Conversely, Black women displayed an association between vigilance and WC, but not between discrimination and WC. These results demonstrate that vigilance and discrimination may hold different meanings for obesity by ethnoracial group that are concealed when all women are examined together and viewed without considering a cultural racism lens.

Child and Adult Socioeconomic Status and the Cortisol Response to Acute Stress: Evidence From the Multi-Ethnic Study of Atherosclerosis.

OBJECTIVE: A long-hypothesized pathway through which low socioeconomic status (SES) harms health is through dysregulation of the physiologic stress response systems. No previous studies have tested this hypothesis by investigating cortisol reactivity and recovery to acute stress in relation to SES at different times in the life course in adults. Alteration of the cortisol response to an acute stressor could signal dysregulation of the hypothalamic-pituitary-adrenal axis and has been associated with chronic illness. METHODS: We used data on 997 adults 54 years or older from a multiethnic, multisite United States study to examine associations between life course SES and cortisol response to a laboratory stress challenge. Informed by life course theory, we hypothesized that lower child and adult SES would be associated with lower reactivity (i.e., smaller increase in cortisol) and a slower recovery rate (i.e., slower rate of decline in cortisol after the challenge). RESULTS: In demographics-adjusted multilevel piecewise linear regression models, low child and adult SES were associated with a 19% (95% CI = 4%-50%) and 27% (7%-55%) slower recovery rate compared with high child and adult SES, respectively. Compared with participants with stable high SES, those with stable low SES had a 48% (16%-70%) slower recovery rate. Differences in reactivity by SES were small. CONCLUSIONS: Our results support the hypothesis that low SES throughout life affects the hypothalamic-pituitary-adrenal axis and in turn the ability to recover from exposure to acute stressors. This mechanism can help explain how socioeconomic disparities contribute to disparities in chronic disease.

Structural racism in the workplace: Does perception matter for health inequalities?

Structural racism has been linked to racial health inequalities and may operate through an unequal labor market that results in inequalities in psychosocial workplace environments (PWE). Experiences of the PWE may be a critical but understudied source of racial health disparities as most adults spend a large portion of their lives in the workplace, and work-related stress affects health outcomes. Further, it is not clear if the objective characteristics of the workplace are important for health inequalities or if these inequalities are driven by the perception of the workplace. Using data from the 2008 to 2012 waves of the Health and Retirement Study (HRS), a probability-based sample of US adults 50 years of age and older and the Department of Labor's Occupational Information Network (O*NET), we examine the role of both standardized, objective (O*NET) and survey-based, subjective (as in HRS) measures of PWEs on health and Black-White health inequalities. We find that Blacks experience more stressful PWEs and have poorer health as measured by self-rated health, episodic memory function, and mean arterial pressure. Mediation analyses suggest that these objective O*NET ratings, but not the subjective perceptions, partially explain the relationship between race and health. We discuss these results within the extant literature on workplace and health and health inequalities. Furthermore, we discuss the use of standardized objective measures of the PWE to capture racial inequalities in workplace environment.

Maternal Social Disadvantage and Newborn Telomere Length in Archived Dried Blood Spots from the Michigan Neonatal Biobank.

Telomeres are the protective caps at the ends of eukaryotic chromosomes. Short telomere length is associated with morbidity and mortality among adults and may mark the biological impact of social experiences. Using archived dried blood spots from the Michigan Neonatal Biobank, this study examined markers of maternal social disadvantage (educational attainment, receipt of public assistance, marital status, and race/ethnicity) from linked birth certificates as predictors of telomere length at birth in a sample of 192 singleton neonates born to non-Hispanic black, non-Hispanic white, and Latina mothers aged 20-35 years. Consistent with two recent studies in newborns, but counter to the idea that maternal social disadvantage is associated with shorter offspring telomere length, we found that infants born to black mothers had longer telomeres than those born to white mothers (b = 0.12, SE = 0.06, p = .05). However, black/white differences in newborn telomere length varied by receipt of public assistance. Among newborns whose mothers received WIC and/or Medicaid, there were no significant black/white differences in telomere length (b = 0.09, SE = 0.08, p = .25). In contrast, among those whose mothers did not receive public assistance-just 6 out of 69 infants born to black mothers versus 41 out of 69 infants born to white mothers-we found that babies born to black mothers had longer telomere length than babies born to white mothers (b = 0.37, SE = 0.16, p = .03). The interaction between black race/ethnicity and receipt of public assistance did not reach the conventional threshold for statistical significance (b = -0.22, SE = 0.15, p = .13), suggesting that this finding may be due to chance. No other markers of maternal social disadvantage were related to infant telomere length. Although replication of these results in a larger sample with more infants born to black mothers with relatively high socioeconomic status is needed, this study offers preliminary support for the hypothesis that race/ethnic differences in newborn telomere length depend on social context.

Measurement and modeling of race and health in Brazil: continuing the discussion.

Recent reviews have discussed the conceptualization of race in health studies in Brazil. This review further documents and discusses specific measurement and modeling issues with regard to race and how this can impact result interpretation. Three scientific databases were used to search the literature on race and three health outcomes. The search yielded 38 empirical studies on birth outcomes, self-rated health, and weight. Results suggest that, while there are racial patterns in the overall literature, conceptual and methodological challenges can be addressed to clarify the ways in which racial group membership is linked to health.

Measurement and modeling of race and health in Brazil: continuing the discussion / Medição e modelagem de raça e saúde no Brasil: continuando a discussão / Medición y modelización de raza y salud en Brasil: continuando la discusión

Recent reviews have discussed the conceptualization of race in health studies in Brazil. This review further documents and discusses specific measurement and modeling issues with regard to race and how this can impact result interpretation. Three scientific databases were used to search the literature on race and three health outcomes. The search yielded 38 empirical studies on birth outcomes, self-rated health, and weight. Results suggest that, while there are racial patterns in the overall literature, conceptual and methodological challenges can be addressed to clarify the ways in which racial group membership is linked to health.

Recentes revisões têm discutido a conceitualização da raça em estudos sobre saúde no Brasil. Esta revisão descreve e discute temas específicos de medição e modelização de raça e como isso pode impactar a interpretação de resultados. Três bases de dados científicas foram usadas para buscar a literatura sobre raça e três resultados em saúde. A pesquisa encotnrou 38 estudos empíricos sobre os resultados do parto, auto-avaliação da saúde e peso. Os resultados sugerem que, embora existam padrões raciais na literatura em geral, os desafios conceituais e metodológicos podem ser abordados para esclarecer as formas em que a adesão ao grupo racial está ligada à saúde.

Recientes revisiones han discutido la conceptualización de la raza en estudios de la salud en el Brasil. Esta revisión documenta y discute temas específicos de medición y modelización con respecto a la raza y cómo esto puede impactar la interpretación de resultados. Tres bases de datos científicas fueron utilizadas para buscar la literatura sobre raza y tres resultados de salud. La búsqueda encontró 38 estudios empíricos sobre los resultados del nacimiento, la autoevaluación de la salud y el peso. Los resultados sugieren que, si bien hay patrones raciales en la literatura general, desafíos conceptuales y metodológicos pueden ser abordados para aclarar las formas en que la pertenencia a grupos raciales está vinculada a la salud.

Air Pollution, Cardiovascular Outcomes, and Social Disadvantage: The Multi-ethnic Study of Atherosclerosis.

BACKGROUND: Social factors may enhance health effects of air pollution, yet empirical support is inconsistent. The interaction of social and environmental factors may only be evident with long-term exposures and outcomes that reflect long-term disease development. METHODS: We used cardiac magnetic resonance imaging data from the Multi-Ethnic Study of Atherosclerosis to assess left-ventricular mass index (LVMI) and left-ventricular ejection fraction (LVEF). We assigned residential concentrations of fine particulate matter (PM2.5), oxides of nitrogen, and nitrogen dioxide in the year 2000 to each participant in 2000 using prediction models. We examined modifying roles of four measures of adversity: race/ethnicity, racial/ethnic residential segregation, and socioeconomic status and psychosocial adversity as composite indices on the association between air pollution and LVMI or LVEF. RESULTS: Compared with whites, blacks showed a stronger adjusted association between air pollution and LVMI. For example, for each 5 µg/m greater PM2.5 level, whites showed a 1.0 g/m greater LVMI (95% confidence interval = -1.3, 3.1), while blacks showed an additional 4.0 g/m greater LVMI (95% confidence interval = 0.3, 8.2). Results were similar for oxides of nitrogen and nitrogen dioxide with regard to black race and LVMI. However, we found no evidence of a modifying role of other social factors or ethnic groups. Furthermore, we found no evidence of a modifying role for any social factors or racial/ethnic groups on the association between air pollution and LVEF. CONCLUSIONS: Our results suggest that racial group membership may modify the association between air pollution and cardiovascular disease.

Invited Commentary: Fundamental Causes, Social Context, and Modifiable Risk Factors in the Racial/Ethnic Inequalities in Blood Pressure and Hypertension.

Racial and ethnic inequalities in blood pressure and hypertension have been well documented, but their causes remain unclear, making efforts to reduce these inequalities challenging. In this issue of the Journal, Basu et al. (Am J Epidemiol. 2015;182(4):345-353) address this gap in our knowledge by using an econometric approach to examine the role of 4 conventional risk factors for hypertension. Their results suggest that targeting certain risk factors will reduce racial inequalities in the prevalence of hypertension. However, racial differences in modifiable risk factors are enmeshed within disparate socioenvironmental contexts which are in turn determined by inequalities in the distribution of social, economic, and political resources and constraints. A small but growing body of literature suggests that targeting the intermediate risk factors that link racial group membership to hypertension, rather than the context or the inequalities in the distribution of resources and constraints, will ultimately result in little change in hypertension inequalities, increase these inequalities, or even create inequalities in poor mental health.

Matching the Genotype in Resolution: Innovative Ways of Phenotype Capture.

Social and spatial context are important determinants of morbidity and mortality. However, there is little clarity about the role of context for kidney disease specifically, particularly before the end stage. Meanwhile, research clarifying the clinical, cellular, molecular, and genetic causes of kidney disease is accelerating considerably. We postulate that without contextual information, even the most detailed biomedical information cannot fully capture the factors that ultimately drive the development and progression of kidney disease. The Nephrotic Syndrome Study Network is integrating detailed, state-of-the-art information on a social and spatial context to enable the exploration of the associations between the social environment and kidney disease. Here, we discuss the extant literature on social context and kidney disease, present information on sources of contextual information, and provide recommended further reading to facilitate future research on the contribution of the social context to kidney disease.

"Every shut eye, ain't sleep": The role of racism-related vigilance in racial/ethnic disparities in sleep difficulty.

Although racial/ethnic disparities in health have been well-characterized in biomedical, public health, and social science research, the determinants of these disparities are still not well-understood. Chronic psychosocial stress related specifically to the American experience of institutional and interpersonal racial discrimination may be an important determinant of these disparities, as a growing literature in separate scientific disciplines documents the adverse health effects of stress and the greater levels of stress experienced by non-White compared to White Americans. However, the empirical literature on the importance of stress for health and health disparities specifically due to racial discrimination, using population-representative data, is still small and mixed. In this paper, we explore the association between a novel measure of racially-salient chronic stress - "racism-related vigilance" - and sleep difficulty. We found that, compared to the White adults in our sample, Black (but not Hispanic) adults reported greater levels of vigilance. This vigilance was positively associated with sleep difficulty to similar degrees for all racial/ethnic groups in our sample (White, Black, Hispanic). Black adults reported greater levels of sleep difficulty compared to White adults. This disparity was slightly attenuated after adjustment for education and income. However, this disparity was completely attenuated after adjustment for racism-related vigilance. We found similar patterns of results for Hispanic compared to White adults, however, the disparities in sleep difficulty were smaller and not statistically significant. Because of the importance of sleep quality to health, our results suggest that the anticipation of and perseveration about racial discrimination is an important determinant of racial disparities in health.

Cumulative social risk and racial/ethnic disparities in obesity during the transition to adulthood.

Racial/ethnic disparities in adolescent obesity in the U.S. are stark, and the causes of these disparities are largely unknown. We used a cumulative risk index (CRI) to examine the role of social risk in racial/ethnic disparities in obesity. Using the National Longitudinal Study of Adolescent Health and multinomial logistic regression, we examined the role of this CRI in disparities in obesity in the transition from adolescence to adulthood. Controlling for sociodemographic characteristics, compared with White females, Black and Hispanic females had roughly a 50% increase in the odds of newly-developed obesity in adulthood and a 90% increase in the odds of persistent obesity in adolescence and adulthood. After adding our CRI, the Black-White disparities were attenuated to statistical non-significance. Hispanic-White disparities did not change. There were no disparities in obesity for males. Our results suggest that social risk factors accumulate to explain Black-White disparities in obesity for females.

Cardiovascular disease among Black Americans: comparisons between the U.S. Virgin Islands and the 50 U.S. states.

OBJECTIVES: Consistent findings show that black Americans have high rates of cardiovascular disease (CVD) and related behavioral risk factors. Despite this body of work, studies on black Americans are generally limited to the 50 U.S. states. We examined variation in CVD and related risk factors among black Americans by comparing those residing within the U.S. Virgin Islands (USVI) with those residing in the 50 U.S. states and Washington, D.C. (US 50/DC) and residing in different regions of the US 50/DC (Northeast, Midwest, South, and West). METHODS: Using data from the 2007 and 2009 Behavioral Risk Factor Surveillance System, we compared CVD and CVD risk factor prevalence in non-Hispanic black people (≥20 years of age) in the USVI and US 50/DC, examining the relative contributions of health behaviors, health insurance, and socioeconomic status (SES). RESULTS: Accounting for age, sex, education, health insurance, and health behaviors, US 50/DC black Americans were significantly more likely than USVI black people to report ever having a stroke and coronary heart disease, and to be hypertensive, diabetic, or obese. While there was heterogeneity by region, similar patterns emerged when comparing the USVI with different regions of the US 50/DC. CONCLUSION: USVI black people have lower CVD and risk factor prevalence than US 50/DC black people. These lower rates are not explained by differences in health behaviors or SES. Understanding health in this population may provide important information on the etiology of racial/ethnic variation in health in the U.S. and elsewhere, and highlight relevant public health policies to reduce racial/ethnic group disparities.