A study published December 21, 2021, in Proceedings of the National Academy of Sciences (PNAS) focused on the cardiovascular health of a multiethnic sample of 4,779 middle-aged people living in 949 neighborhoods in seven U.S. cities: Los Angeles; New York; Chicago; Saint Paul, Minnesota; Minneapolis; Winston-Salem, North Carolina; and Baltimore. Back in the 1930s, maps used by the federal Home Owner’s Loan Corporation (HOLC) graded each of these neighborhoods based on discriminatory assessments of how risky it would be to issue mortgages to prospective home buyers, according to the study. On these maps, the most “hazardous” places to issue loans were colored in red and had high proportions of Black, low-income, and immigrant residents; predominantly white and affluent communities were colored green to indicate the “safest” places for banks to offer mortgages. Overall, about 19 percent of study participants lived in “hazardous” redlined neighborhoods, while roughly 5 percent lived in the “best” communities. Using these historical HOLC maps, researchers examined the cardiovascular health of modern-day residents of each neighborhood, using factors such as blood pressure, blood sugar, cholesterol, overweight and obesity, diet, physical activity, and smoking.
Surprising Findings
On the basis of these risk factors, Black people who lived in historically redlined neighborhoods had much worse cardiovascular health than Black people living elsewhere. But this wasn’t the case for the three other groups examined in the study: white, Hispanic, and Chinese people. “We were surprised by these findings,” says the lead study author, Mahasin Mujahid, PhD, an associate professor of epidemiology in the school of public health at the University of California in Berkeley. “We had hypothesized that our findings would be more pronounced among Black participants, but that there would still be associations for other racialized groups.” Poorer health outcomes for Black people living in historically redlined neighborhoods persisted across several different risk factors for poor heart health, the study found. For example, Black people in these neighborhoods were 78 percent less likely to have healthy blood pressure and 60 percent less likely to have a healthy body weight. “Our findings are an important reminder that Black people have a different history in this country, from slavery through Reconstruction, Jim Crow and the civil rights movement,” Dr. Mujahid says. “The effects of this unique history continue to shape the current reality of Black Americans in relation to health outcomes, especially heart health.”
Study Limitations
One limitation of the study is that factors not directly measured in the analysis, such as socioeconomic status, may have impacted heart health outcomes for Black people. Redlined neighborhoods often tended to be high-poverty communities, and unfair lending practices often coincided with discrimination in employment and other aspects of life that could also negatively impact health, the researchers noted. On top of this, redlining prevented Black families from passing accumulated wealth — in the form of a family home — on to subsequent generations, Mujahid says. Homeownership is one of the most common ways that families in the United States are able to move into the middle class and allow their children to achieve more financial success. Even though redlining may technically be a thing of the past, structural racism and discrimination persist in contributing to worse health outcomes for Black people, several studies suggest. One study, published in October 2015 in the American Journal of Public Health, for example, found that people living in communities with higher levels of anti-Black prejudice were 24 percent more likely to die prematurely than individuals living in more tolerant neighborhoods. Another study looked at who in New York City gets care at academic medical centers that provide access to advanced treatments and technologies that aren’t available elsewhere. This study, published in February 2017 in the International Journal of Health Services, found that Black patients were half as likely as white patients to receive care at academic medical centers even after accounting for differences in health insurance.
Can Moving Help?
It’s also possible that moving out of segregated communities to more diverse neighborhoods may help Black people improve their heart health. A study published in July 2017 in JAMA Internal Medicine found significant improvements in blood pressure among Black people who moved to less-segregated communities. This isn’t a sure thing, however, because even though Black people who move away from historically redlined communities improve their chances of upward mobility and higher earnings, they also may leave behind strong social support networks that can be beneficial for their health, Mujahid says. Whether Black people remain in historically redlined neighborhoods or move away, they need to be vigilant about the potential for their health to be shaped by where they were born and how generations of their family lived, Mujahid adds. “Clinicians and health providers should recognize that many of their patients experience worse health because of intergenerational effects from policies that were racist or discriminatory,” Mujahid says. “Redlining is just one example, but there are many more examples out there.”
