Spaces of Segregation and Health: Complex Associations for Black Immigrant and US-Born Mothers in New York City

Measuring Spatial Social Polarization in Public Health Research: A Scoping Review of Methods and Applications

Spatial social polarization (SSP) refers to the uneven spatial distribution and subsequent concentration of polarized social and/or economic groups in a specified geographic area. However, there is heterogeneity in how SSP is measured and operationalized in research. To this end, we conducted a scoping review to characterize the use of SSP measures in public health research, providing a foundation for those seeking to navigate this complex literature, select measurement options, and identify opportunities for methodological development. Using a structured search strategy, we searched PubMed for any primary research, published since 2007, that examined the relationship between SSP and health outcomes. Across 117 included studies, we found a body of evidence that was primarily set in the United States (n = 104), published between 2020 and 2022 (n = 52), and focused on non-communicable diseases (n = 40). We found that defining SSP in the context of privilege, deprivation, and segregation returns a variety of measures. Among measures, we categorized 18 of them as SSP measures, with the Index of Concentration at the Extremes (n = 43) being the most common, and 5 of them as composite indices based on numerous underlying variables spanning several domains like education and race/ethnicity. While most employed a single SSP measure (n = 64), some included up to 5 measures to examine the robustness of findings or to identify how a multidimensional approach to SSP affected associations. Our findings fill a critical literature gap by summarizing options for operationalizing SSP measures and documenting their respective methodologies. Future research should consider using multiple SSP measures to capture the multidimensionality of SSP, widen the scope of health outcomes, and clearly explain the choice of measure(s) and methods used to derive them. Our findings can inform future research questions and help guide researchers in the selection and utilization of the various SSP measures.

Systemic racism and Non-Hispanic Black to Non-Hispanic White disparities in infant mortality at the county level

OBJECTIVE

To use a novel measure of systemic racism to examine its relationship with Non-Hispanic Black (NHB) to Non-Hispanic White (NHW) racial disparities in infant mortality across U.S. counties.

STUDY DESIGN

In this cross-sectional study, a composite, multi-dimensional measure of systemic racism at the county level was developed using confirmatory factor analysis based on indicators across five dimensions of systemic racism. Using linear regression analysis, we examined the relationship between the systemic racism factor scores and the NHB to NHW racial disparities in county-level infant mortality rates. Additionally, we performed a multi-level analysis of infant mortality, with births nested within counties by running a random intercept model that controlled for factors at both the individual and county levels to take into account the clustered nature of the data.

RESULTS

There were 325 counties that met inclusion criteria for the county level analysis and 1181 counties for the individual level analysis. Each one standard deviation increase in the Systemic Racism Index was associated with an increase of 10.4% in the Non-Hispanic Black to Non-Hispanic White infant mortality rate ratio at the county level (aOR 1.104, 95% CI [1.061-1.148]). After controlling for individual level clinical factors and county level factors, each one standard deviation increase in the systemic racism index score was associated with a decrease of 3.5% in the NHW infant mortality rate (aOR 0.965, 95% CI [0.943-0.988]).

CONCLUSION

Systemic racism is significantly associated with differences between counties in the magnitude of their Non-Hispanic Black to Non-Hispanic White racial disparities in infant mortality rates.

National Variation in Black Immigrant Preterm Births and the Role of County-Level Social Factors

Preterm birth rates among Black individuals continue to be inequitably high in the USA. Black immigrants appear to have a preterm birth advantage over US-born counterparts. This national cross-sectional study of singleton non-Hispanic Black individuals in the USA from 2011 to 2018 aimed to investigate if the Black immigrant preterm birth advantage varied geographically and how this advantage associated with county-level social drivers of health. Generalized linear mixed models explored the odds of preterm birth (< 37 weeks) by birthing person's nativity, defined as US- versus foreign-born. In county-level analyses, five measures were explored as possible sources of structural risk for or resilience against preterm birth: percent of residents in poverty, percent uninsured, percent with more than a high school education, percent foreign-born, and racial polarization. County-level immigrant advantage among foreign-born compared to US-born Black individuals was defined by a disparity rate ratio (RR); RR < 1 indicated a county-level immigrant preterm birth advantage. Linear regression models at the level of counties quantified associations between county-level factors and disparity RRs. Among 4,072,326 non-Hispanic Black birthing individuals, immigrants had 24% lower adjusted odds of preterm birth compared to US-born Black individuals (aOR 0.77, 95% CI 0.76-0.78). In county-level analyses, the immigrant advantage varied across counties; disparity RRs ranged from 0.13 to 2.82. County-level lack of health insurance and education greater than high school were both associated with immigrant preterm birth advantage. Future research should explore policies within counties that impact risk of preterm birth for both US-born and immigrant Black individuals.

Racial/Ethnic Residential Segregation, Neighborhood Health Care Provision, and Choice of Pediatric Health Care Provider Across the USA

Much research has been conducted that demonstrates a link between racial/ethnic residential segregation and health care outcomes. We suggest that minority segregated neighborhoods may have diminished access to organizations and that this differential access may contribute to differences in health care outcomes across communities. We analyze this specifically using the case of pediatric health care provider choice. To examine this association, we estimate a series of multinomial logistic regression models using restricted data with ZIP code level geoidentifiers from the 2011-2012 National Survey of Children's Health (NSCH). We find that racial/ethnic residential segregation is related to a greater reliance on non-ideal forms of health care, such as clinics, and hospital outpatient departments, instead of pediatric physician's offices. This association is at least partially attenuated by the distribution of health care facilities in the local area, physician's offices, and health care practitioners in particular. Additionally, families express greater dissatisfaction with these other forms of care compared to physician's offices, demonstrating that the lack of adequate health care provision is meaningful for health care outcomes. This study expands the literature by examining how the siting of health organizations has consequences for individuals residing within these areas.

Residential segregation and summertime air temperature across 13 northeastern U.S. states: Potential implications for energy burden

High ambient summertime temperatures are an increasing health concern with climate change. This is a particular concern for minoritized households in the United States, for which differential energy burden may compromise adaptive capacity to high temperatures. Our research question was: Do minoritized groups experience hotter summers than the area average, and do non-Hispanic white people experience cooler summers? Using a fine-scaled spatiotemporal air temperature model and U.S. census data, we examined local (within-county) differences in warm season cooling degree days (CDDs) by ethnoracial group as a proxy for local energy demand for space cooling across states of the northeast and mid-Atlantic U.S. in 2003-2019. Using state-specific regression models adjusted for year and county, we found that Black and Latino people consistently experienced more CDDs, non-Hispanic white people experienced fewer CDDs, and Asian populations showed mixed results. We also explored a concentration-based measure of residential segregation for each ethnoracial group as one possible pathway towards temperature disparities. We included the segregation measure as a smooth term in a regression model adjusted for county and year. The results were nonlinear, but higher concentrations of white people were associated with lower annual CDDs and higher concentrations of Latino people were associated with higher annual CDDs than the county average. Concentrations for Black and Asian people were nonmonotonic, sometimes with bowed associations. These findings suggest that present-day residential segregation, as modeled by spatially smoothed ethnoracial subgroup concentrations, may contribute to summertime air temperature disparities and influence adaptive capacity. We hope these findings can support place-based interventions, including targeting of energy insecurity relief programs.

Structural racism, nativity and risk of adverse perinatal outcomes among Black women

BACKGROUND

Black women in the United States (US) have the highest risk of preterm birth (PTB) and small for gestational age (SGA) births, compared to women of other racial groups. Among Black women, there are disparities by nativity whereby foreign-born women have a lower risk of PTB and SGA compared to US-born women. Differential exposure to racism may confer nativity-based differences in adverse perinatal outcomes between US- and foreign-born Black women. This remains unexplored among US- and African-born women in California.

OBJECTIVES

Evaluate the relationship between structural racism, nativity, PTB and SGA among US- and African-born Black women in California.

METHODS

We conducted a population-based study of singleton births to US- and African-born Black women in California from 2011 to 2017 (n = 131,424). We examined the risk of PTB and SGA by nativity and neighbourhoods with differing levels of structural racism, as measured by the Index of Concentration at the Extremes. We fit crude and age-adjusted Poisson regression models, estimated using generalized estimating equations, with risk ratios (RR) and 95% confidence intervals (CI) as the effect measure.

RESULTS

The proportions of PTB and SGA were 9.7% and 14.5%, respectively, for US-born women, while 5.6% and 8.3% for African-born women. US-born women (n = 24,782; 20.8%) were more likely to live in neighbourhoods with high structural racism compared to African-born women (n = 1474; 11.6%). Structural racism was associated with an elevated risk of PTB (RR 1.19, 95% CI 1.12, 1.26) and SGA (RR 1.19, 95% CI 1.13, 1.25) for all Black women, however, there was heterogeneity by nativity, with US-born women experiencing a higher magnitude of effect than African-born women.

CONCLUSIONS

Among Black women in California, exposure to structural racism and the impacts of structural racism on the risk of PTB and SGA varied by nativity.

Nativity and perinatal outcome disparities in the United States: Beyond the immigrant paradox

In the United States (US), epidemiologists have long documented paradoxically lower rates of adverse perinatal health outcomes among immigrant birthing people than what might be expected in light of socioeconomic and language barriers to healthcare, especially as compared to their US-born racial and ethnic counterparts. However, researchers have also documented significant variability in this immigrant birth paradox when examining within and across racial and ethnic subgroups. This review paper summarizes fifty years of research regarding differences in low, preterm birth, and infant mortality in the US, according to the nativity status of the birthing person. While there is ample evidence of the importance of nativity in delineating a pregnant person's risk of adverse infant outcomes, this review also highlights the relative paucity of research exploring the intersection of acculturation, ethnic enclaves, and structural segregation. We also provide recommendations for advancing the study of perinatal outcomes among immigrants.