Research Spotlight: Regional Disparities in Opioid Overdose Mortality Persist Despite National Decline

Sarah Wakeman, MD, Senior Medical Director for Substance Use Disorder at Mass General Brigham, is the co-senior author and Will Oles, BS, of Harvard Medical School, is a corresponding author of a paper published in the Journal of General Internal Medicine, “Geographic Trends in Opioid and Polysubstance Overdose Deaths in the US, 2014-2023.”

Q: How would you summarize your study for a lay audience?

In May 2024, the Centers for Disease Control (CDC) announced a national decline in the rate of drug overdose deaths for the first time since 2018. However, little is known about how this decline varies by geographic region.

To address this gap, we analyzed US opioid overdose deaths by region, finding that opioid-related mortality increased in the western US despite a decrease in other regions between 2022 and 2023.

This regional divergence was driven by an increase in overdoses due to fentanyl or a combination of fentanyl and stimulants (e.g., methamphetamine).

These findings highlight the evolving nature of the overdose crisis and suggest the need for region-specific strategies to address differing patterns of substance use and overdose risk.

Q: What knowledge gap does your study help to fill?

Given recent reports of national improvements in opioid-related mortality, we sought to understand how trends in opioid overdoses––particularly those involving combinations of opioids with other substances––have shifted over time across different regions of the US.

Q: What methods or approach did you use?

We examined publicly available death certificate data from the CDC’s WONDER database to identify all opioid-related deaths reported in the US between 2014 and 2023.

Q: What did you find?

Between 2022 and 2023, we found that opioid overdose deaths decreased in non-West regions but continued to rise in the western US by 14%.

Beginning in 2019, rates of overdoses that co-involved both fentanyl and a stimulant accelerated across all US regions.

Overdoses involving fentanyl and cocaine were more common in non-West regions, while overdoses involving fentanyl and methamphetamine were more common in the West.

Nationally, around one in three fentanyl-related deaths now involve stimulants, with states in the West nearing one in two.

Q: What are the implications?

Our findings of a continued increase in opioid overdose deaths in the West, masked by a decline in mortality nationally, underscore an ongoing shift in the landscape of the opioid overdose crisis.

The emergence of these distinct overdose patterns highlight the need for ongoing surveillance of these substances in local drug markets, equitable access to medications for opioid use disorder and investment in therapies for stimulant use disorder.

Q: What are the next steps?

Ongoing surveillance of regional opioid mortality trends will be essential as new data emerges nationally. Future research should also investigate the root causes of geographic disparities to help guide targeted public health responses and inform policy development.

Authorship: In addition to Wakeman and Oles, additional authors include Michael Liu and Marc Larochelle.

Paper cited: Oles W C, et al. “Geographic Trends in Opioid and Polysubstance Overdose Deaths in the US, 2014-2023” Journal of General Internal Medicine. DOI: 10.1007/s11606-025-09589-1

Funding: N/A

Disclosures: Dr. Wakeman reported being an author for UpToDate and a textbook editor for Springer and Wolters Kluwer.