Boston Medical Center: opioid overdose deaths 86% higher in Massachusetts tracts graded Hazardous

Researchers at Boston Medical Center (BMC) found that Massachusetts census tracts with the lowest historical redlining grade had 86% higher annual opioid-related overdose death rates than tracts with the highest grade. The study covers deaths in 2015–2019 and was published on 3 November 2026 in the Journal of Health Care for the Poor and Underserved doi.orgJournal of Health Care for the Poor and Underserveddoi.orgOpen source ↗. The work was led by first author Rebecca Smeltzer of the University of Southern California, with Avik Chatterjee, an addiction specialist at BMC, as senior author.

Method: redlining grades and overdose deaths

Redlining maps were created by the Home Owners' Loan Corporation in the 1930s. They assigned neighborhoods grades from "best" to "hazardous", reflecting lending assessments that disadvantaged Black and immigrant communities. The authors assigned a grade to 2010 census tracts using a weighting method and linked it to decedent data and tract population estimates doi.orgJournal of Health Care for the Poor and Underserveddoi.orgOpen source ↗.

The analysis included 326 census tracts, where 1,829 adults died of opioid-related overdoses from 2015 to 2019. The authors used negative binomial regression and robust standard errors to account for spatial autocorrelation (Moran's I p<.001). The models were adjusted for demographics, including race and ethnicity and age composition, and for tract social vulnerability doi.orgJournal of Health Care for the Poor and Underserveddoi.orgOpen source ↗.

Results: rates by grade

Compared with tracts graded Best, five-year annual death rates were 53% higher in Still Desirable tracts (adjusted incidence rate ratio 1.53, 95% CI 1.03–2.28). They were 61% higher in Declining tracts (aIRR 1.61, 95% CI 1.07–2.43) and 86% higher in Hazardous tracts (aIRR 1.86, 95% CI 1.18–2.93) doi.orgJournal of Health Care for the Poor and Underserveddoi.orgOpen source ↗.

The authors say the findings point to long-term effects of historical disinvestment on where overdose risk is concentrated. According to the Massachusetts Department of Public Health, cited in the BMC release, opioid-related overdose deaths in the state fell nearly 60% from 2022 to 2025 and dropped below 1,000 for the first time in more than a decade. The authors note that such gains may not be shared equally across communities.

Limitations

The researchers state that the study identifies an association and does not establish that redlining caused the differences in death rates. The analysis was limited to census tracts with sufficient historical mapping coverage. It excluded nonurban communities that had not received redlining grades. Chatterjee said that policies strengthening housing, economic opportunity, healthcare access and community resources may play a role in reducing overdoses.