Historical structural racism impacts modern-day breast cancer outcomes

Key takeaways:

• Living in historically redlined areas raised odds for estrogen receptor-negative status, late diagnosis and breast cancer mortality.
• Persistent mortgage discrimination was tied to mortality for white vs. Black women.

U.S. policies built around racism and persistent discrimination impact modern-day breast cancer outcomes, with worse outcomes for women living in historically redlined areas, according to study findings published in JAMA Network Open.

“Discriminatory policies and laws in the U.S. have perpetuated institutional and structural racism, which have profoundly affected various aspects of society, including education, health care, economics and housing, ultimately affecting neighborhoods,” Jasmine M. Miller-Kleinhenz, PhD, a previous postdoctoral fellow in the department of epidemiology at the Rollins School of Public Health at Emory University and assistant professor at the University of Mississippi Medical Center, and colleagues wrote. “Recent research has shown that historical redlining, a form of mortgage discrimination that was largely based on the racial and ethnic composition of neighborhoods, is a contributing factor to racial disparities in breast cancer outcomes, including diagnosis at later stages and with estrogen receptor-negative breast cancer.”

Miller-Kleinhenz and colleagues conducted a population-based cohort study with data from 1,764 non-Hispanic Black and white women diagnosed with breast cancer who lived in areas graded by the Home Owners’ Loan Corporation in Georgia. All women were diagnosed with a first primary breast cancer from 2010 to 2017 and were followed until December 2019. Researchers evaluated scores for historical redlining, with less than 2.5 defining non-redlined areas and 2.5 or greater defining redlined areas.

Primary outcomes were estrogen receptor status, late-stage breast cancer at diagnosis and breast cancer-specific mortality.

In total, 48.5% of women were non-Hispanic Black and 51.5% were non-Hispanic white. Overall, 65.1% of women were diagnosed with breast cancer at age 55 years or older. Of all participants, 30.5% lived in historically non-redlined areas and 69.5% lived in historically redlined areas.

Among women living in historically redlined areas, compared with those living in areas without redlining, non-Hispanic Black women had 62% increased odds of estrogen receptor-negative breast cancer (22.1% vs. 13.9%; OR = 1.62; 95% CI, 1.01-2.6), and non-Hispanic white women had 97% increased odds of late-stage breast cancer diagnosis (14.5% vs. 8.9%; OR = 1.97; 95% CI, 1.15-3.36). In addition, women living in historically redlined areas had a 60% increase in breast cancer mortality overall (HR = 1.6; 95% CI, 1.17-2.18).

According to the researchers, persistent mortgage discrimination was associated with breast cancer mortality for non-Hispanic white women (HR = 2.17; 95% CI, 1.13-4.18) but not for non-Hispanic Black women.

“Our observations reinforce the concept of race as a social construct and emphasize the need for a more nuanced investigation of the differing social and structural drivers of disparate breast cancer outcomes,” the researchers wrote. “Additional methods and approaches are needed to capture the intersecting influences from multiple social and structural domains on race disparities in breast cancer mortality.”