Independent and joint contributions of economic, social and physical environmental characteristics to mortality in the Detroit Metropolitan Area: A study of cumulative effects and pathways

Neighborhood Environment, DNA Methylation, and Presence of Crown-Like Structures of the Breast

Importance

Inflammation impacts cancer risk and tumor biological processes, yet studies linking it to social and environmental risk factors are lacking.

Objective

To investigate the association of neighborhood deprivation and air pollution with breast adipose inflammation as well as the association between crown-like structures of the breast (CLS-B) and DNA methylation in Black and White women.

Design, Setting, and Participants

This cross-sectional study analyzed women with and without breast cancer participating in the National Cancer Institute-Maryland Breast Cancer Study, most of whom were recruited between January 1, 1993, and December 1, 2003, from the University of Maryland Medical Center and surrounding hospitals in the Baltimore, Maryland, area. A small subset of the sample was recruited between March 27, 2012, and November 27, 2017. Noncancerous breast tissue was collected from women who underwent reduction mammoplasty or breast cancer surgery. Statistical analyses were conducted between May and August 2024.

Exposures

Two socioenvironmental exposures were examined: air pollution (specifically, fine particulate matter less than 2.5 μm in diameter [PM2.5]) and neighborhood deprivation (measured with Neighborhood Deprivation Index [NDI]). Participant geocodes were linked to 2000 US Census data to calculate PM2.5 concentrations (total mass [μg/m3]) and NDI.

Main Outcomes and Measures

Breast tissues underwent immunohistochemical staining for pan-macrophage marker CD68 to detect 2 outcomes: CLS-B and adipose-associated macrophages. CLS-B and adipose-related macrophages were assessed by pathologists using artificial intelligence-assisted and manual approaches. Covariate-adjusted logistic regression models were used to ascertain associations between PM2.5 and NDI (exposures) and presence or absence of CLS-B (outcome); CD68-positive adipose macrophages were modeled as a dichotomous high or low variable. Covariate-adjusted linear regression was used to identify associations between CLS-B (exposure) and DNA methylation (outcome).

Results

The cohort included 205 participants (127 Black [62.0%], 78 White [38.0%] women; mean [SD] age, 48.7 [13.3] years). Women with vs without CLS-B had higher median (IQR) body mass index (calculated as weight in kilograms divided by height in meters squared; 35.5 [30.5-40.9] vs 31.8 [26.6-36.4]; P = .02). Higher levels of PM2.5 (odds ratio [OR], 2.32; 95% CI, 1.12-4.78; P = .02) and NDI (OR, 1.21; 95% CI, 1.02-1.43; P = .03) were associated with presence of CLS-B overall; findings were still significant among Black women (PM2.5: OR, 2.64 [95% CI, 1.10-6.33], P = .03; NDI: OR, 1.22 [95% CI, 1.01-1.48], P = .04) but were not statistically significant among White women (PM2.5: OR, 1.65 [95% CI, 0.45-5.99], P = .45; NDI: OR, 1.19 [95% CI, 0.83-1.70], P = .35). Higher PM2.5 concentration was associated with increased macrophage infiltration (OR, 2.11; 95% CI, 1.24-3.60; P = .006), with similar outcomes by race. The top 2 significant differentially methylated CpG sites by CLS-B status were SAR1B (β = 0.01; 95% CI, 0.01-0.02; P < .001) and IL2RB (β = -0.04; 95% CI, -0.05 to -0.02; P < .001). Significant interaction was observed between CLS-B status and race for IL2RB methylation levels (β = -0.03; 95% CI, -0.04 to -0.01; P for interaction <.001).

Conclusions and Relevance

This cross-sectional study uncovered an association between neighborhood-level social and environmental risk factors and breast tissue inflammation. The findings help inform efforts to reduce racial and socioeconomic disparities in breast cancer and improve health equity for socially vulnerable populations.

Racial Composition of Social Environments Over the Life Course Using the Pictorial Racial Composition Measure: Development and Validation Study

BACKGROUND

Studies investigating the impact of racial segregation on health have reported mixed findings and tended to focus on the racial composition of neighborhoods. These studies use varying racial composition measures, such as census data or investigator-adapted questions, which are currently limited to assessing one dimension of neighborhood racial composition.

OBJECTIVE

This study aims to develop and validate a novel racial segregation measure, the Pictorial Racial Composition Measure (PRCM).

METHODS

The PRCM is a 10-item questionnaire of pictures representing social environments across adolescence and adulthood: neighborhoods and blocks (adolescent and current), schools and classrooms (junior high and high school), workplace, and place of worship. Cognitive interviews (n=13) and surveys (N=549) were administered to medically underserved patients at a primary care clinic at the Barnes-Jewish Hospital. Development of the PRCM occurred across pilot and main phases. For each social environment and survey phase (pilot and main), we computed positive versus negative pairwise comparisons: mostly Black versus all other categories, half Black versus all other categories, and mostly White versus all other categories. We calculated the following validity metrics for each pairwise comparison: sensitivity, specificity, correct classification rate, positive predictive value, negative predictive value, positive likelihood ratio, negative likelihood ratio, false positive rate, and false negative rate.

RESULTS

For each social environment, the mostly Black and mostly White dichotomizations generated better validity metrics relative to the half Black dichotomization. Across all 10 social environments in the pilot and main phases, mostly Black and mostly White dichotomizations exhibited a moderate-to-high sensitivity, specificity, correct classification rate, positive predictive value, and negative predictive value. The positive likelihood ratio values were >1, and the negative likelihood ratio values were close to 0. The false positive and negative rates were low to moderate.

CONCLUSIONS

These findings support that using either the mostly Black versus other categories or the mostly White versus other categories dichotomizations may provide accurate and reliable measures of racial composition across the 10 social environments. The PRCM can serve as a uniform measure across disciplines, capture multiple social environments over the life course, and be administered during one study visit. The PRCM also provides an added window into understanding how structural racism has impacted minoritized communities and may inform equitable intervention and prevention efforts to improve lives.

Climate change and cancer: the Environmental Justice perspective

Despite advances in cancer control-prevention, screening, diagnosis, treatment, and survivorship-racial disparities in cancer incidence and survival persist and, in some cases, are widening in the United States. Since 2020, there's been growing recognition of the role of structural racism, including structurally racist policies and practices, as the main factor contributing to historical and contemporary disparities. Structurally racist policies and practices have been present since the genesis of the United States and are also at the root of environmental injustices, which result in disproportionately high exposure to environmental hazards among communities targeted for marginalization, increased cancer risk, disruptions in access to care, and worsening health outcomes. In addition to widening cancer disparities, environmental injustices enable the development of polluting infrastructure, which contribute to detrimental health outcomes in the entire population, and to climate change, the most pressing public health challenge of our time. In this commentary, we describe the connections between climate change and cancer through an Environmental Justice perspective (defined as the fair treatment and meaningful involvement of people of all racialized groups, nationalities, or income, in all aspects, including development, implementation, and enforcement, of policies and practices that affect the environment and public health), highlighting how the expertise developed in communities targeted for marginalization is crucial for addressing health disparities, tackling climate change, and advancing cancer control efforts for the entire population.

The impact of air pollution on neurocognitive development: Adverse effects and health disparities

Air pollution is recognized as a major public health concern. The number of deaths related to ambient air pollution has increased in recent years and is projected to continue rising. Additionally, both short- and long-term air pollution exposure has been linked with deleterious effects on neurocognitive function and development. While air pollution poses as a threat to everyone, people of color and individuals of lower socioeconomic status are often exposed to elevated levels of air pollution as a function of systemic racism and classism. Further, given additional disparities in access to healthcare and other compounding stressors, adverse effects of air pollution on neurocognitive health are exacerbated among individuals who hold marginalized identities-making effects both less likely to be detected and treated. This review examines evidence of the effects of air pollution on neurocognitive development across the lifespan and incorporates an environmental justice perspective to highlight disparities in air pollution exposure across race and socioeconomic status. Last, upon the reviewed evidence, limitations of past research and recommendations for policy are discussed.

Spatial Decomposition of Air Pollution Concentrations Highlights Historical Causes for Current Exposure Disparities in the United States

Racial-ethnic disparities in exposure to air pollution in the United States (US) are well documented. Studies on the causes of these disparities highlight unequal systems of power and longstanding systemic racism-for example, redlining, white flight, and racial covenants-which reinforced racial segregation and wealth gaps and which concentrated polluting land uses in communities of color. Our analysis is based on empirical estimates of ambient concentrations for two important pollutants (NO2 and PM2.5). We show that spatially decomposed concentrations can be used to infer and quantify types of root causes for local- to national-scale disparities. Urban-scale segregation is important yet reflects less than half of the overall national disparities. Other historical causes of national exposure disparities include those that led current populations of Black, Asian, and Hispanic Americans to live in larger cities; those outcomes are consistent with, for example, greater economic opportunity in large cities, land-takings from non-White farmers, and racism in homesteading and between-state migration. Our results suggest that contemporary national exposure disparities in the US reflect a broad set of historical local- to national-scale mechanisms-including racist laws and actions that include, but also extend beyond, urban-scale aspects-and offer a first attempt to quantify their relative importance.

The impact of social and environmental factors on cancer biology in Black Americans

Low socioeconomic status (SES) is associated with early onset of chronic diseases and reduced life expectancy. The involvement of neighborhood-level factors in defining cancer risk and outcomes for marginalized communities has been an active area of research for decades. Yet, the biological processes that underlie the impact of SES on chronic health conditions, such as cancer, remain poorly understood. To date, limited studies have shown that chronic life stress is more prevalent in low SES communities and can affect important molecular processes implicated in tumor biology such as DNA methylation, inflammation, and immune response. Further efforts to elucidate how neighborhood-level factors function physiologically to worsen cancer outcomes for disadvantaged communities are underway. This review provides an overview of the current literature on how socioenvironmental factors within neighborhoods contribute to more aggressive tumor biology, specifically in Black U.S. women and men, including the impact of environmental pollutants, neighborhood deprivation, social isolation, structural racism, and discrimination. We also summarize commonly used methods to measure deprivation, discrimination, and structural racism at the neighborhood-level in cancer health disparities research. Finally, we offer recommendations to adopt a multi-faceted intersectional approach to reduce cancer health disparities and develop effective interventions to promote health equity.

Fixed Effect Estimates of Student-Teacher Racial or Ethnic Matching in U.S. Elementary Schools

We used student fixed effects and statistical controls to investigate whether U.S. elementary students (N = 18,170) displayed greater academic achievement, social-emotional behavior, or executive functioning and were more likely to receive gifted or special education services when taught by teachers of the same race or ethnicity. We observed mostly null effects for student-teacher racial or ethnic matching across the study's 12 dependent measures in analyses adjusting for Type 1 error. For the full sample, matching resulted in lower science achievement (effect size [ES] = -.03 SD). For Black students, matching resulted in fewer internalizing problem behaviors (ES = 0.18 SD). We observed null effects for Hispanic students. Robustness checks including those stratified by race or ethnicity and biological sex or by prior levels of low or high level of achievement, behavior, or executive functioning largely supported the study's null findings. Exceptions were that matching resulted in fewer externalizing problem behaviors (ES = 0.22 SD) for Black girls and lower academic achievement (ES range = -0.04 to -0.14 SD) and fewer externalizing and internalizing problem behaviors (ES range = 0.24 to 0.33 SD) for students who had previously displayed low levels of academic, behavioral, or executive functioning. Collectively, the analyses provide limited support for student-teacher racial or ethnic matching as a school-based policy to address educational disparities in U.S. elementary schools.

A Bibliometric Analysis on Research Regarding Residential Segregation and Health Based on CiteSpace

Considerable scholarly attention has been directed to the adverse health effects caused by residential segregation. We aimed to visualize the state-of-the-art residential segregation and health research to provide a reference for follow-up studies. Employing the CiteSpace software, we uncovered popular themes, research hotspots, and frontiers based on an analysis of 1211 English-language publications, including articles and reviews retrieved from the Web of Science Core Collection database from 1998 to 2022. The results revealed: (1) The Social Science & Medicine journal has published the most studies. Roland J. Thorpe, Thomas A. LaVeist, Darrell J. Gaskin, David R. Williams, and others are the leading scholars in residential segregation and health research. The University of Michigan, Columbia University, Harvard University, the Johns Hopkins School of Public Health, and the University of North Carolina play the most important role in current research. The U.S. is the main publishing country with significant academic influence. (2) Structural racism, COVID-19, mortality, multilevel modelling, and environmental justice are the top five topic clusters. (3) The research frontier of residential segregation and health has significantly shifted from focusing on community, poverty, infant mortality, and social class to residential environmental exposure, structural racism, and health care. We recommend strengthening comparative research on the health-related effects of residential segregation on minority groups in different socio-economic and cultural contexts.

Childhood obesity within the lens of racism

Despite decades of research and a multitude of prevention and treatment efforts, childhood obesity in the United States continues to affect nearly 1 in 5 (19.3%) children, with significantly higher rates among Black, Indigenous, and People of Colour communities. This narrative review presents social foundations of structural racism that exacerbate inequity and disparity in the context of childhood obesity. The National Institute of Minority Health and Health Disparities' Research Framework guides the explication of structurally racist mechanisms that influence health disparities and contribute to childhood obesity: biologic and genetic, health behaviours, chronic toxic stress, the built environment, race and cultural identity, and the health care system. Strategies and interventions to combat structural racism and its effects on children and their families are reviewed along with strategies for research and implications for policy change. From our critical review and reflection, the subtle and overt effects of societal structures sustained from years of racism and the impact on the development and resistant nature of childhood obesity compel concerted action.

Does air pollution contribute to urban-rural disparity in male lung cancer diseases in China?

It remains unknown whether exposure to ambient air pollution can be a mediator linking socioeconomic indicator to health outcome. The present study aims to examine the mediation effect of PM2.5 air pollution on the association between urban-rural division and the incidence (mortality) rate of male lung cancer. We performed a nationwide analysis in 353 counties (districts) of China between 2006 and 2015. A structural equation model was developed to determine the mediation effect of exposure to PM2.5. We also tested whether the findings of the mediation effect of exposure to PM2.5 are sensitive to the controls of smoking factors and additional air pollutant, and PM2.5 exposures with different lag structures. According to the results, we found that exposure to PM2.5 significantly mediated the association between urban-rural division and the incidence rate of male lung cancer. Specifically, there were significant associations between urban-rural division, exposure to PM2.5, and the incidence rate of male lung cancer, with PM2.5 exposure accounting for 29.80% of total urban-rural difference in incidence rates of male lung cancer. A similar pattern of results was observed for the mortality rate of male lung cancer. That is, there was a significant mediation effect by PM2.5 on the association of the mortality rate with urban-rural division. The findings of exposure to PM2.5 as a mediator were robust in the three sensitivity analyses. In conclusion, urban-rural difference in exposures to PM2.5 may be a potential factor that contributes to urban-rural disparity in male lung cancer diseases in China. The findings inform that air pollution management and control may be effective measures to alleviate the great difference in male lung cancer diseases between urban and rural areas in China.

All-cause mortality and residential racial and ethnic segregation and composition as experienced differently by individual-level race, ethnicity, and gender: Mortality disparities in american communities data

PURPOSE

Use a large nationally representative population to evaluate whether differences in mortality in relation to residential racial and ethnic segregation and diversity varied by gender, and race or Hispanic ethnicity in the United States.

METHODS

The Mortality Disparities in American Communities (MDAC) was used to evaluate mortality risk in relation to segregation. MDAC is a nationally representative record linkage of the 2008 American Community Survey data with mortality outcomes derived from the National Death Index through 2015. Gender-stratified mortality risk for White, Black, and Hispanic groups in relation to quartiles of residential segregation, composition, and diversity were modeled using parametric survival regression with an exponential distribution, adjusted for individual-level socioeconomic characteristics.

RESULTS

The study population included >3,950,000 individuals and >273,000 all-cause mortality outcomes. Statistically significant differences in associations were observed with Black segregation vs. Hispanic segregation across Black or Hispanic groups; some differences in stratification by gender for Hispanic and Non-Hispanic Black groups, but gender-stratified associations were more similar in non-Hispanic Whites.

CONCLUSIONS

Future multidisciplinary and ethnographic research is needed to identify the specific structural mechanisms by which these associations differ to support means by which to more effectively target public health interventions.

Association between disparities in intergenerational economic mobility and cause-specific mortality among Black and White persons in the United States

BACKGROUND

Evidence about the association between structural racism and mortality in the United States is limited. We examined the association between ongoing structural racism, measured as inequalities in adulthood income between White and Black children with similar parental household income (economic mobility gap) in a recent birth cohort, and Black-White disparities in death rates (mortality gap) overall and for major causes.

METHODS

Sex-, race/ethnicity-, and county-specific data were used to examine sex-specific associations between economic mobility and mortality gaps for all causes combined, heart diseases, cerebrovascular diseases, chronic obstructive pulmonary disease (COPD), injury/violence, all malignant cancers, and 14 cancer types. Economic mobility data for 1978-1983 birth cohorts and death rates during 2011-2018 were obtained from the Opportunity Atlas and National Center for Health Statistics, respectively. Data from 471 counties were included in analyses of all-cause mortality at ages 30-39 years during 2011-2018 (corresponding to partially overlapping 1978-1983 birth cohorts); and from 1,572 and 1,248 counties in analyses of all-cause and cause-specific mortality in all ages combined, respectively.

RESULTS

In ages 30-39 years, a one percentile increase in the economic mobility gap was associated with a 6.8 % (95 % confidence interval 1.8 %-11.8 %) increase in the Black-White mortality gap among males and a 13.5 % (8.9 %-18.1 %) increase among females, based on data from 471 counties. In all ages combined, the corresponding percentages based on data from 1,572 counties were 10.2 % (7.2 %-13.2 %) among males and 14.8 % (11.4 %-18.2 %) among females, equivalent to an increase of 18.4 and 14.0 deaths per 100,000 in the mortality gap, respectively. Similarly, strong associations between economic mobility gap and mortality gap in all ages were found for major causes of death, notably for potentially preventable conditions, including COPD, injury/violence, and cancers of the lung, liver, and cervix.

CONCLUSIONS

Economic mobility gap conditional on parental income in a recent birth cohort as a marker of ongoing structural racism is strongly associated with Black-White disparities in all-cause mortality and mortality from several causes.

Still striding toward social justice? Redirecting physical activity research in a post-COVID-19 world

The COVID-19 crisis and parallel Black Lives Matter movement have amplified longstanding systemic injustices among people of color (POC). POC have been differentially affected by COVID-19, reflecting the disproportionate burden of ongoing chronic health challenges associated with socioeconomic inequalities and unhealthy behaviors, including a lack of physical activity. Clear and well-established benefits link daily physical activity to health and well-being—physical, mental, and existential. Despite these benefits, POC face additional barriers to participation. Thus, increasing physical activity among POC requires additional considerations so that POC can receive the same opportunities to safely participate in physical activity as Americans who are White. Framed within the Ecologic Model of Physical Activity, this commentary briefly describes health disparities in COVID-19, physical activity, and chronic disease experienced by POC; outlines underlying putative mechanisms that connect these disparities; and offers potential solutions to reduce these disparities. As behavioral medicine leaders, we advocate that solutions must redirect the focus of behavioral research toward community-informed and systems solutions.