An American Heart Association peer-reviewed study finds that Blacks still living in once-redlined districts have an 8% greater chance of heart attacks.
DALLAS – An American Heart Association (AHA) analysis of more than two million U.S. adults found that present day heart failure risk is higher among Black adults living in zip codes historically impacted by redlining than Black adults now living in non-redlined areas.
The peer-reviewed study, which was published in AHA’s journal, Circulation, found that white adults living in historically redlined zip codes don’t see an increased rate of heart failure.
The analysis, published as part of the journals Disparities in Cardiovascular Medicine Special Issue, included more than 2.3 million adults from 2014-2019 who lived in U.S. communities with varying degrees of redlining, which began in the mid-1930s.
What is redlining?
In 1933, the Home Owners Loan Corporation (HOLC) – a government agency created as part of President Roosevelt’s New Deal – began sponsoring low-interest mortgage loans to help people recover from the financial crisis of the Great Depression.
In a process called redlining, however, the HOLC developed a color-coding system for neighborhoods based on investment risk. Its red areas, which were largely Black communities, were considered too risky to insure mortgages.
As a result, red-lined neighborhood residents were denied home loans, which lowered tax revenues and reduced their investment in schools and government programs and services, a problem that impacted multiple generations until redlining was outlawed under the Fair Housing Act of 1968.
According to AHA, previous research found that once-redlined communities had higher rates of stroke, as well as increased risk of hypertension, Type 2 diabetes and early mortality due to heart disease.
Heart failure is a progressive condition in which the heart is unable to pump enough blood to the body either due to the heart muscle stiffening or from the loss of pumping strength. According to the American Heart Association’s 2023 Statistical Update, heart failure affects 6.7 million people in the U.S. and disproportionately impacts Black adults.
Housing and health
“The relationship between historic redlining practices and health today gives us unique insight into how historical policies may still be exerting their effects on the health of many communities,” says study co-senior author Shreya Rao, a cardiologist and assistant professor in the department of internal medicine at the University of Texas Health Science Center.
The researchers identified nearly 2.4 million adults in the Medicare Beneficiary Summary Files between 2014 and 2019 with linked residential zip codes. Participants were excluded from the analysis if they had a history of heart failure or heart attack in the preceding two years, had fewer than two years of Medicare coverage before the study start date or were younger than the age of 40. The researchers mapped historical redlining maps onto modern day maps of 1,044 zip codes in the U.S. and sorted them into four groups ranging from zip codes that had the least amount of area impacted by redlining to zip codes with the most areas exposed to redlining.
“Ultimately, we were most interested in assessing the difference in risk of heart failure between individuals from communities with the highest level of exposure to redlining and individuals from other communities,” says first author Amgad Mentias, an interventional cardiology fellow at Cleveland Clinic in Cleveland, Ohio.
The analysis found:
- Black adults in zip codes with the highest proportion of redlining had an 8% higher risk of developing heart failure compared to Black adults living in communities with low levels of redlining.
- In contrast, white adults living in zip codes with the highest proportion of redlining did not have an increased risk of heart failure.
- About half of the excess risk of heart failure among Black adults living in redlined communities was explained by higher levels of socioeconomic distress (determined by Social Deprivation Index scores) in those communities.
- The risk of heart failure was highest in Black adults living in redlined communities that had high scores on the Social Deprivation Index.
“The findings also highlight the pivotal role housing plays as a social determinant of health,” Pandey says. “Aggressive enforcement of anti-discrimination laws in housing, and support for and pathways to homeownership for Black families are needed in order to begin to achieve equity in health.”
The study does have limitations, however, according to the authors, because redlining is only one facet of discrimination. It does not alone “capture the full contribution of systemic racism on health today,” the authors say.
© 2023 Florida Realtors®