A new study from researchers at Boston Medical Center (BMC), the largest essential hospital in New England, found that Massachusetts neighborhoods given the lowest grades on historic redlining maps had 86% higher annual opioid-related overdose death rates than those given the highest grades. The study, published in the Journal of Health Care for the Poor and Underserved , suggests that the long-term effects of historical disinvestment continue to affect health outcomes based on where people live.
Massachusetts has made meaningful progress in reducing opioid-related overdose deaths. According to the Massachusetts Department of Public Health , opioid-related overdose deaths fell nearly 60% from 2022 to 2025, falling below 1,000 for the first time in more than a decade. However, these improvements may not be shared equally across communities due to longstanding structural inequities that continue to shape overdose risk.
"Addressing the opioid overdose crisis requires understanding the broader social and structural factors that shape health outcomes. Where people live, the resources available to their communities, and the lasting effects of historical disinvestment all matter," says Avik Chatterjee, MD, MPH, addiction specialist at BMC and senior author on the study.
Redlining maps, created by the Home Owners' Loan Corporation in the 1930s, assigned neighborhoods grades ranging from "best" to "hazardous." Those grades reflected discriminatory lending assessments that disadvantaged Black and immigrant communities and contributed to long-term disinvestment. Researchers used the maps to calculate a historical redlining grade for each of 326 Massachusetts census tracts, where 1,829 adults died from opioid-related overdoses from 2015 to 2019.
"Our findings suggest that overdose risk is influenced not only by individual factors, but also by long-standing structural inequities tied to place and community investment," says Rebecca Smeltzer, first author on the study and PhD student at the University of Southern California.
The pattern extended across the other grading categories. Compared with census tracts classified as "best," adjusted opioid-related overdose death rates were 53% higher in those classified as "still desirable" and 61% higher in those classified as "declining." These differences remained statistically significant after accounting for race and ethnicity, neighborhood age composition, and social vulnerability, a measure of social and economic conditions.
"Additional investment to redress historical disinvestment is an opportunity to help address overdose death risk in these neighborhoods," says Dr. Chatterjee, "Policies that strengthen housing, economic opportunity, healthcare access, and community resources may play an important role in reducing overdoses for all communities."
The researchers note that the study identifies an association and does not establish that historical redlining caused the differences in overdose death rates. The analysis was limited to census tracts with sufficient historical mapping coverage and excluded nonurban communities that had not received redlining grades.
