BUFFALO, N.Y. – In neighborhoods across America, women face a daunting threat from a federal practice that, although it was outlawed decades ago, continues to negatively impact their health today.
That's according to the findings of new University at Buffalo research that examines how historical redlining — the federal policy from the 1930s where neighborhoods were given mortgage security grades based on race, ethnicity, class status and land use — impacts both present-day breast cancer factors and survival after diagnosis.
The Federal Housing Administration (FHA) began redlining in 1934, denying prospective homeowners access to credit based solely on where they lived, oftentimes in urban neighborhoods that had large populations of Black residents. Neighborhoods were assigned grades from A to D. Marked on a map in green, 'A' neighborhoods were deemed the best, while 'D' areas were marked in red and considered hazardous. The practice was made illegal in 1968.
"While it is a near-century-old residential segregation policy, redlining still has influences on a neighborhood's breast cancer environment, and a woman's survival," says Sarah M. Lima, the lead author on both studies, who will graduate this May with her PhD in epidemiology from UB's School of Public Health and Health Professions. Lima's study on redlining and breast cancer survival was published in Cancer Epidemiology, Biomarkers & Prevention ; the paper on redlining and clustering of breast cancer factors was published in January in the journal Cancer Causes & Control .
"Historical redlining is a really interesting factor to study with breast cancer because it ties neighborhood environmental profiles to socioeconomic factors," explains Lima, who focused on the increasing rates of breast cancer among younger women while working toward her master's at Columbia University, where she also worked on a breast cancer study prior to coming to UB.
Lima credits her UB advisors, Heather Ochs-Balcom, PhD , associate professor, and Tia Palermo, PhD, research associate professor, both in the Department of Epidemiology and Environmental Health and co-authors on the two papers, with helping to identify the connection between redlining and breast cancer.
Homeownership and wealth continue to be much lower in redlined neighborhoods, which also were used as sites to build highways and industrial facilities, Lima says. As a result, those neighborhoods continue to have higher exposure to pollution and toxic waste, and fewer parks and trees.
"Redlining affected the design of U.S. cities and determined much of today's environmental profiles and socioeconomic resources in neighborhoods — that makes it a type of perfect storm for breast cancer," according to Lima.
Progressively lower survival by redlining grade
The study on redlining and survival after breast cancer diagnosis showed that regardless of a woman's health insurance status, the treatments she received and the socioeconomic status of her neighborhood, she is more likely to die within five years of her diagnosis simply based on whether her neighborhood was redlined or not.
In fact, it showed that redlining was associated with progressively lower survival for each grade among breast cancer cases. The study was based on nearly 61,000 breast cancer cases in New York State from 2008-2018.
Among the 60,773 cases, only 5.6% were in A-graded neighborhoods, compared to 21.7% for B, 42.5% in C, and 30.1% in D neighborhoods. Breast cancer cases in B, C and D areas had a 1.29, 1.37 and 1.64-fold higher risk of death compared to cases in A areas.
In addition, the study found that worse redlining grades had a higher prevalence of worse prognostic factors, including distant stage or metastatic cancer and more aggressive forms of breast cancer like hormone receptor-negative tumors and triple-negative breast cancer.
"These results tell us that the differences in survival by historical redlining are not just due to differences in the resources of the people who live there, but that there's something about the neighborhoods themselves that have an effect," says Lima, who encourages women who live in historically redlined areas to make sure they are up to date on breast cancer screenings.
The study was conducted in collaboration with New York State Department of Health cancer epidemiologists Tabassum Insaf, PhD, and Furrina Lee, PhD, who provided guidance with the state cancer registry data.
"This project demonstrates the power of population-based cancer surveillance data and how it can be used to understand how factors related to places in which we live and work can influence cancer survival," says Insaf, who serves as director of the state Department of Health's Bureau of Cancer Epidemiology and scientific director for the New York State Cancer Registry. "Through our New York State Cancer Registry, the New York State Department of Health is proud to partner with University at Buffalo to contribute to our understanding of cancer disparities."
Additional UB co-authors are Lili Tian, professor of biostatistics; Henry-Louis Taylor Jr., professor in the Department of Urban and Regional Planning; and Deborah O. Erwin, research professor of epidemiology and environmental health and professor of oncology at Roswell Park Comprehensive Cancer Center.
Differences among regions
The paper looking at clustering of breast cancer risk and survival factors complements the survival research by explaining how the neighborhoods may influence breast cancer survival.
This study examined 12,894 neighborhoods around the U.S., 74% of which were historically redlined. Researchers found that high-risk breast cancer factors were more common in redlined neighborhoods than non-redlined, with the exception of binge drinking, which was more prominent among non-redlined communities.
While historically redlined areas had an average of 5.41 breast cancer factors at high-risk levels, non-redlined neighborhoods averaged 3.55. High school education, lack of health insurance and physical inactivity were most strongly correlated to historical redlining status. Efforts to improve education, income, healthy lifestyles and mammography in redlined areas could help boost survival, Lima says.
Interestingly, this study revealed differences across U.S. regions (Northeast, South, Midwest and West) and is believed to be the first to evaluate historical redlining with geographic distribution of established breast cancer factors.
The identification of geographic differences could be used to help health departments in those areas think about useful interventions to reverse factors that contribute to higher risk for breast cancer, Lima says. For example, the disparities discovered in the South region would suggest that health practitioners there should focus on reducing obesity and smoking and improving physical activity, particularly for residents of redlined communities.
In the West, however, increasing mammography and routine medical care access would be more beneficial.
In addition to Taylor and Tian, Jared Aldstadt, associate professor in the Department of Geography, is also a UB co-author on this paper.
Taken together, Lima says, "Our results suggest that redlining determines a person's environment and access to health resources, which, in turn, affects their health. While redlining was outlawed long ago, that doesn't mean the pathways it helped establish are gone."
