Neighborhood Characteristics and Racial Disparities in Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Seropositivity in Pregnancy

Abstract

Objective: To quantify the extent to which neighborhood characteristics contribute to racial and ethnic disparities in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) seropositivity in pregnancy.

Methods: This cohort study included pregnant patients who presented for childbirth at two hospitals in Philadelphia, Pennsylvania from April 13 to December 31, 2020. Seropositivity for SARS-CoV-2 was determined by measuring immunoglobulin G and immunoglobulin M antibodies by enzyme-linked immunosorbent assay in discarded maternal serum samples obtained for clinical purposes. Race and ethnicity were self-reported and abstracted from medical records. Patients' residential addresses were geocoded to obtain three Census tract variables: community deprivation, racial segregation (Index of Concentration at the Extremes), and crowding. Multivariable mixed effects logistic regression models and causal mediation analyses were used to quantify the extent to which neighborhood variables may explain racial and ethnic disparities in seropositivity.

Results: Among 5,991 pregnant patients, 562 (9.4%) were seropositive for SARS-CoV-2. Higher seropositivity rates were observed among Hispanic (19.3%, 104/538) and Black (14.0%, 373/2,658) patients, compared with Asian (3.2%, 13/406) patients, White (2.7%, 57/2,133) patients, and patients of another race or ethnicity (5.9%, 15/256) (P<.001). In adjusted models, per SD increase, deprivation (adjusted odds ratio [aOR] 1.16, 95% CI 1.02-1.32) and crowding (aOR 1.15, 95% CI 1.05-1.26) were associated with seropositivity, but segregation was not (aOR 0.90, 95% CI 0.78-1.04). Mediation analyses revealed that crowded housing may explain 6.7% (95% CI 2.0-14.7%) of the Hispanic-White disparity and that neighborhood deprivation may explain 10.2% (95% CI 0.5-21.1%) of the Black-White disparity.

Conclusion: Neighborhood deprivation and crowding were associated with SARS-CoV-2 seropositivity in pregnancy in the prevaccination era and may partially explain high rates of SARS-CoV-2 seropositivity among Black and Hispanic patients. Investing in structural neighborhood improvements may reduce inequities in viral transmission.

Figure 1.

Cohort development

Figure 2.

A. Map of seropositivity rates in census tracts with at least 20 study participants. Study participants lived in other tracts, but rates would be too unstable and individuals too identifiable to depict. B. Map of segregation using the index of the concentration of extremes (ICE). Higher values indicate higher proportion of White residents. C. Map of neighborhood deprivation index includes six indicators and ranges from 0 to 1, with 1 indicating more deprivation. D. Map of crowding defined as the proportion of residences with more humans than rooms in the house. Maps created using ArcGIS software by Esri. ArcGIS and ArcMap are the intellectual property of Esri and are used herein under license. Copyright Esri. All rights reserved. For more information about Esri software, please visit www.esri.com. Census tract boundaries, water features, segregation, and crowding data are from the U.S. Census Bureau (https://www.census.gov). Neighborhood deprivation index data are from Brokamp’s Nationwide Community Deprivation Index (https://github.com/geomarker-io/dep_index)

Figure 3.

Proportion (and 95% confidence intervals) of the racial and ethnic disparity in SARS-CoV-2 seropositivity at the end of pregnancy mediated by neighborhood factors. Neighborhood deprivation index includes six indicators and ranges from 0 to 1 with 1 indicating more deprivation; Segregation assigned using index of the concentration of extremes (ICE), higher values indicate higher proportion White residents. Crowding defined as the proportion of residences with more humans than rooms in the house.