Widening Racial and Gender Inequities Reported in Polysubstance Overdose Deaths

U.S. overdose deaths involving polysubstance use—particularly opioids combined with stimulants—have risen sharply in recent years, with disproportionate increases among non-Hispanic Black and Hispanic populations, especially men. While the role of different patterns of polysubstance use in driving these disparities is still under study, findings from a new paper at Columbia University Mailman School of Public Health and Vagelos College of Physicians & Surgeons provide compelling and comprehensive evidence linking these patterns to inequities in overdose mortality. The results are published in the journal Addiction.

Polysubstance use—defined as the intentional or unintentional use of two or more drugs over varying timeframes—can intensify physiological risks, including cardiovascular strain and respiratory depression.

“The United States is in the fourth wave of the overdose crisis, driven by polysubstance use,” said Kechna Cadet, PhD, assistant professor in the Department of Epidemiology, Columbia Mailman School of Public Health, and first author. “In recent years, Black men and women have been disproportionately affected compared to their White counterparts. Our study offers a comprehensive, contemporary analysis of opioid-only, opioid-stimulant, and opioid-benzodiazepine deaths across race, ethnicity, and gender. By understanding who is experiencing the highest burden of these overdose patterns, we can better tailor our treatment and harm reduction services to those who need it the most.”

The research team analyzed national overdose death records from 2004 to 2022 using the CDC’s WONDER Multiple Cause of Death database. Trends in age-adjusted mortality rates were assessed using joinpoint regression developed by the National Cancer Institute.

The study included individuals of all ages across all 50 states and Washington, D.C., categorized into six groups: non-Hispanic White men and women, non-Hispanic Black men and women, and Hispanic men and women. In total, the analysis captured 627,793 opioid-only deaths, 196,001 opioid-stimulant deaths, and 117,322 opioid-benzodiazepine deaths.

Key findings include:
•    Opioid-involved deaths increased across all groups, with the largest rise among non-Hispanic Black men, particularly after 2011.
•    Opioid-stimulant deaths showed the steepest increases among non-Hispanic Black men (39.5 percent annually from 2011–2022) and Black women (36 percent).
•    Among Hispanic men, opioid-stimulant deaths rose sharply by 34 percent annually from 2012–2022.
•    Opioid-benzodiazepine deaths remained lower overall but showed widening disparities, with the highest increases among non-Hispanic White men and women.

Across all categories, non-Hispanic Black men experienced the highest absolute increase in opioid-only mortality rates (53.55 per 100,000), followed by non-Hispanic White men (31.05) and Hispanic men (24.19). Among women, non-Hispanic Black women had the highest annual average increase (15 percent), with notable acceleration after 2013.

“Our findings highlight rapidly widening racial and ethnic disparities in overdose deaths,” said Cadet, who is also in the Department of Emergency Medicine at Columbia University Vagelos College of Physicians & Surgeons. “Yet treatment guidelines have not kept pace with the growing crisis. Additionally, to date, there are no pharmacotherapies for stimulant use disorder approved by the FDA.”

Black and Hispanic individuals remain less likely to receive medications for opioid use disorder compared to White individuals. Structural factors—including unequal access to care, lack of insurance, poverty, and medical mistrust—continue to drive these disparities. 

The authors emphasize the need for more equitable and targeted responses.

“Future research should examine how overlapping systems of oppression, including racism and sexism, create distinct vulnerabilities,” said Silvia Martins, MD, PhD, professor of Epidemiology at Columbia Mailman School, and senior author of the study. “We also call for more consistent toxicology testing and reporting across jurisdictions.”

Martins and Cadet urge policymakers to use these findings to better target harm reduction strategies and invest in equity-focused and gender-responsive interventions.

“Despite clear evidence of need, current federal priorities fall short in supporting equity-based research and tailored interventions for polysubstance use,” Martins concludes.
A co-author is Paige Brinzo, MS, Schmidt College of Medicine, Florida Atlantic University.

The study is supported by the Columbia University Data Science Institute Seed Funding (Substance Abuse Epidemiology Training Grant, T32DA031099, R01DA059376 and the NIH Loan Repayment Program, L60DA061545, National Institute of Drug Abuse.

The authors report no financial conflicts of interest.