(63) A Novel Index to Assess Association Between Structural Racism and Black/White Stillbirth Rate Disparities

Racial disparities in stillbirth rates are well-documented but the association with structural racism has not been adequately studied. Using the Structural Racism Index, a novel index that assesses Black/White disparities in multiple socioeconomic indicators and quantifies exposure to systemic inequalities, this study investigates the relationship between structural racism and Black/White stillbirth rate disparities across US counties.

Study Design: Using CDC Vital Statistics data from 2016 - 2019, stillbirth rates were calculated for non-Hispanic Black (NHB) compared to non-Hispanic White (NHB) populations at the county level. The Structural Racism Index (SRI) and its relationship to differences in stillbirth rates by race was studied. Analyses were restricted to counties with more than 50,000 Black residents and at least 10 stillbirths to assure model stability. Linear regression of the stillbirth rate were performed and adjusted for county level access to resources using the CDC’s Social Vulnerability Index (SVI) and other county level socioeconomic factors.

Results:

A total of 149 counties, representing 150 million residents and 70% of the US Black population, met inclusion criteria. The average stillbirth rate  was 10.4 in the NHB population versus 5.3 per 1000 in the NHW population. After adjusting for SVI, each standard deviation increase in the SRI score still resulted in a 12% increase in the rate of stillbirth disparity (aOR 1.12, 95% CI 1.07-1.17). The disparity in rates was not explained by county level differences in social vulnerability as measured by the SVI or county level factors like education, unemployment, or poverty.

Conclusion: There are significant racial disparities in rates of stillbirth between NHB and NHW populations at the US county level and structural racism as measured by the Structural Racism Index is strongly associated with these differences. Measures such as the CDC’s SVI do not adequately account for the differences observed thus other measures such as the SRI should be considered to better understand how exposure to structural racism leads to worse health outcomes.