Impact of Historical Redlining and Neighborhood SES on Breast Cancer Survival

Overview

This study of 60,773 invasive breast cancer cases in New York State found that historical redlining is associated with increased 5-year mortality risk. Approximately half of this association is mediated by contemporary neighborhood socioeconomic conditions, while the other half is directly attributable to historical redlining.

Background

Historical redlining was a 1930s federally backed residential segregation policy that graded neighborhoods from A (best) to D (hazardous) based on race, class, and land use. Although outlawed in 1968, the socioeconomic and environmental disparities created by redlining persist and contribute to health disparities, including breast cancer survival. Prior research has linked redlining to worse breast cancer outcomes, but the role of current neighborhood socioeconomic status (NSES) as a mediator or modifier of this relationship remains unclear. Understanding these pathways is critical for developing targeted interventions to reduce breast cancer mortality disparities.

Data Highlights

Key Findings

• Historical redlining grade D (hazardous) is associated with a 20% increased risk of 5-year mortality compared to grade A (best).
• Contemporary neighborhood socioeconomic condition mediates approximately half of the association between historical redlining and breast cancer survival.
• No significant interaction was detected between historical redlining and current neighborhood socioeconomic status on survival.
• The mediation effect was consistent among hormone receptor-positive, local-stage, and regional-stage tumors, but not among hormone receptor-negative or distant-stage tumors.
• Decomposition of effects varied by race/ethnicity, indicating differential impacts across populations.

Clinical Implications

Interventions aimed at improving contemporary neighborhood socioeconomic conditions may reduce breast cancer survival disparities rooted in historical redlining. Clinicians and public health practitioners should consider neighborhood context as a factor influencing patient outcomes and target resources accordingly. Addressing socioeconomic barriers in historically redlined areas could attenuate mortality risk among breast cancer patients.

Conclusion

Historical redlining continues to influence breast cancer survival disparities, with contemporary neighborhood socioeconomic conditions mediating a substantial portion of this effect. Targeted interventions addressing current neighborhood SES may help mitigate the long-term adverse impacts of redlining on breast cancer outcomes.

References

1. New York State Cancer Registry-based cohort study (2024) -- The Impact of Historical Redlining on Breast Cancer Survival