In parts of cities once marked "hazardous" on federal housing maps, an ambulance is still more likely to show up late than in neighborhoods that bankers favored nearly a century ago, according to a national analysis of 236 urban areas.
Rutgers researchers found that 7.06 % of residents in historically redlined Grade D tracts (considered "hazardous") lacked rapid access to emergency medical services compared with 4.36 % in Grade A tracts, a gap that held across every U.S. region.
The study in JAMA Network Open used modern traffic data, 2020 Census block groups and historic Home Owners' Loan Corporation (HOLC) maps to trace drive times from 42,472 emergency medical service (EMS) stations. The researchers found that 2.2 million of the 41 million people (5.34%) living inside the mapped zones cannot count on an ambulance arriving within five minutes, the National Fire Protection Association's benchmark for critical calls.
The odds of EMS response times exceeding 5 minutes were 67% higher in the "redlined" neighborhoods that fell in the lowest of HOLC's four color-coded rankings nearly a century ago.
Lead author Cherisse Berry, a professor of surgery and vice chair of academic surgery at the Rutgers New Jersey Medical School in Newark, said the pattern shows how a New Deal lending program still shapes who survives a stroke or car crash.
"Location alone determines whether people get the rapid care that saves lives," said Berry, who is also a trauma surgeon and director of research and trauma surgeon at University Hospital's Eric Munoz Trauma Center.
Berry's team overlaid today's street grid on the color-coded HOLC grades, green for "best," blue for "still desirable," yellow for "declining" and red for "hazardous." (The grades were mostly used in the 30s, but their usage was not outlawed until 1968.) The researchers then measured the distance from each census block's population center to the nearest EMS station, adjusting for average driving speeds.
The persistent inequity between differently coded neighborhoods emerged everywhere, but it was starkest in the Great Lakes. Residents of redlined parts of cities there were nearly three times as likely to be beyond the five-minute reach of an ambulance.
The findings echo earlier work by the same group that mapped areas called "ambulance deserts," but Berry said this study is the first to tie EMS inequities directly to redlining. Because delays before hospital arrival raise trauma mortality by 8% for every extra 10 minutes, members of the team argue that targeting EMS systems development and investing resources in EMS operations with health equity in mind could yield immediate health gains.
The researchers also compared demographic data and found that redlined tracts still hold more Black and Hispanic residents, higher population density and lower median incomes than their Grade A counterparts. These persistent inequities, the researchers said, reflect the historical racist housing policy of redlining-a political determinant of health that produced residential segregation, concentrated poverty, and community disinvestment-and a structural determinant of health that has shaped the distribution of resources and opportunities, leading to inequitable EMS access and enduring adverse health outcomes.
Berry said improving EMS equity will take more than adding stations: "It is time to dismantle the structural determinants of health that perpetuate preventable deaths. Historical redlining and other discriminatory policies have hardwired inequities into our emergency response systems, leaving racially and economically marginalized communities to wait longer for lifesaving care.
"We must redesign prehospital systems to achieve spatial justice-by embedding equity metrics into EMS policy, targeting investments to historically excluded neighborhoods, and holding agencies accountable for equitable access," she added. "National and state health policy must treat equitable EMS access as a non-negotiable public health standard, ensuring that the zip code where someone is injured never determines whether they live or die."
She and co-authors urge creating public dashboards, using geographic information system tools to reposition units, and adding equity metrics to certificate-of-need reviews.
Policy shifts could matter quickly in places where residents already face longer 911 wait times and higher rates of chronic illness. By shortening ambulance drives even a minute or two, Berry said, "we can cut mortality significantly."
The study has limits beyond the usual note that correlation doesn't prove causation. Most importantly, it models travel distance, not real-world response records that include dispatch delays, traffic or hospital hand-offs. Still, outside experts argue in an accompanying editorial that the work offers a road map for righting persistent wrongs.
