Key Points

  • Drug overdose deaths dropped 26% in 2024, the second consecutive year of decline, with alcohol-related deaths and suicide rates also falling, according to a Trust for America’s Health report.
  • A study of 606,434 U.S. veterans found GLP-1 medications linked to 14% lower odds of developing a new substance use disorder, with lower risk spanning alcohol, nicotine, cannabis, cocaine, and opioids.
  • Among veterans who already had a substance use disorder, GLP-1 users had roughly 40% fewer overdoses and about half as many drug-related deaths over three years.
  • The GLP-1 findings come from an observational study, not a randomized clinical trial. The study population was primarily older male veterans with type 2 diabetes, and results may not apply to younger people or those without diabetes.
  • Oxford researchers found that people diagnosed with opioid use disorder were 56% more likely to develop dementia, with genetic analysis suggesting the link reflects opioid exposure rather than confounding factors alone.

Addiction News Weekly Episode 1.3

In This Episode:

Welcome back to Addiction News Weekly from Rehab.com, your weekly read on the science shaping recovery. This week, two major studies, both built on the health records of hundreds of thousands of veterans, are changing how we think about treating addiction. We’ll start with the big picture, because this week it was cautiously hopeful.

Overdose Deaths Fall for the Second Straight Year

A new national report from the Trust for America’s Health found that drug overdose deaths fell 26% in 2024, the second straight year of decline.1,2 Alcohol-related deaths and suicide deaths fell as well. The report credits wider access to medications for opioid use disorder and to harm reduction.

So, the question researchers are now racing to answer is how to build on that progress. Two studies out this week, both drawn from veteran health data, offer real clues. The first study looks at a class of drugs you have probably heard of for weight loss, the GLP-1 medications like semaglutide.

GLP-1 Medications May Reduce Addiction Risk Across Substances

Researchers at Washington University in St. Louis reviewed the health records of more than 600,000 veterans with type 2 diabetes, comparing those on GLP-1 drugs to those on a different diabetes medication. Among people who did not have a substance use disorder, GLP-1 users were 14% less likely to develop one, with lower risk across alcohol, nicotine, cannabis, cocaine, and opioids. And among people who already had a substance use disorder, the drugs were linked to fewer overdoses and fewer drug-related deaths.

The findings were published in the BMJ.3 For what this means clinically, here’s Dr. Sylvie Stacy.

It’s really exciting to see research pointing towards something that could potentially turn down what many of my patients describe as a constant mental pull towards substances. Many people call it drug noise. I’ve had plenty of patients tell me that they get exhausted from spending so much of their day thinking about using drugs, even when they’re really trying hard not to.

At the same time, this study does have some limits. It looked at medical records. It’s not a randomized clinical trial, so it shows an association rather than proving cause and effect. And in terms of the study population, these were mostly older male veterans with type 2 diabetes. We can’t automatically assume the same results would apply to younger people or people without diabetes.

One thing that did stick out to me was how consistent the findings were across different substances. The reduced risk showed up with alcohol, nicotine, cannabis, cocaine, and opioids. So that suggests that these medications are affecting a shared pathway that’s involved in rewards, cravings, and reinforcement.

For people who already had a substance use disorder, the differences were pretty large. The study found roughly 40% fewer overdoses and about half as many drug-related deaths over three years. The results are especially interesting for stimulant use disorders. I regularly work with people struggling with methamphetamine or cocaine addiction, and it’s often frustrating we still don’t have any FDA-approved medications for these. I think the right takeaway from this study is that the findings are promising and they absolutely warrant clinical trials. That’s a necessary step to getting FDA approval for addiction indications.

Opioid Use Disorder Is Linked to Higher Dementia Risk

Our second study this week stays with veteran data, but it turns from treatment to a long-term risk we are only beginning to understand. Researchers at Oxford, publishing in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association, drew on more than 220,000 records from the U.S. Million Veteran Program.4 They found that people diagnosed with opioid use disorder were 56% more likely to develop dementia than people without that diagnosis. The part that caught researchers’ attention is that they used genetic analysis to separate opioid exposure from other risk factors, like chronic pain or alcohol use. And the links still pointed to the opioids themselves.

Dr. Stacy, this is a heavier finding. Help us understand what it does and does not mean.

This is a concerning finding, but it also fits with what many of us have worried about for years when it comes to the long-term effects of opioid use. What makes this study particularly interesting is that the researchers used genetic methods to help separate opioid exposure from some other factors that often muddy the waters, like chronic pain, mental health conditions, and alcohol use. The proposed explanation also makes sense from a medical standpoint. Over time, opioid use can contribute to changes that reduce healthy blood flow and oxygen delivery to the brain. That happens through effects on blood vessels, repeated infections, and episodes of fluctuating blood pressure. When you look at these factors together over many years, you can see how they could contribute to cognitive decline.

One challenge I see clinically is that early cognitive problems can be easy to miss in people with an active addiction. Memory issues, difficulty concentrating, changes in behavior — those things often get attributed to substance use itself, but sometimes there’s more going on there. For me, this reinforces the importance of getting people onto effective treatment as early as possible. Medications like buprenorphine and methadone help stabilize patients and reduce those repeated cycles of intoxication and withdrawal that put stress on the body and brain.

So I don’t want people to hear about this study and be worried, but rather the message is that treatment matters. The longer we help people stay healthy and stable, the better chance we have of protecting their lives and their long-term brain health.

Thank you, Dr. Stacy.

Conclusion

Both of these studies point in the same direction. When people get into treatment and stay in it, the benefits reach further than we used to think, into overdose risk, into long-term brain health, across substance after substance, which brings us back to where we started. That same national report that delivered the good news in 2024 also carried a warning. The federal agency that funds much of this work, SAMHSA, lost roughly half its workforce over the past two years, and proposed Medicaid cuts could narrow access further. The progress is real. However, the report’s own word for it was fragile.

If you or someone you love is struggling, help is available right now. You can reach out to the SAMHSA National Helpline, free and confidential at 1-800-662-4357, or find treatment options near you at rehab.com. And that’s the week. We read the research so you don’t have to chase it. Find sources and past episodes at rehab.com/podcast. I’m Kay. Take care of yourself, and we’ll see you next week.

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Sources in This Episode

  1. Gracia JN; Trust for America’s Health. Deaths Due to Drug Overdose and Alcohol Are Down Nationally, But Progress Is Uneven Across Population Groups and at Risk Due to Cuts in Federal Health Programs. Trust for America’s Health; May 28, 2025. https://www.tfah.org/article/deaths-due-to-drug-overdose-and-alcohol-are-down-nationally-but-progress-is-uneven-across-population-groups-and-at-risk-due-to-cuts-in-federal-health-programs/. Accessed June 17, 2026.
  2. National Center for Health Statistics. Drug Overdose Deaths in the United States, 2023–2024. NCHS Data Brief No. 549. Centers for Disease Control and Prevention; May 14, 2025. https://www.cdc.gov/nchs/products/databriefs/db549.htm. Accessed June 17, 2026.
  3. Cai M, Choi T, Xie Y, Al-Aly Z. Glucagon-like peptide-1 receptor agonists and risk of substance use disorders among US veterans with type 2 diabetes: cohort study. BMJ. 2026;392:e086886. doi:10.1136/bmj-2025-086886.
  4. Javidnia V, et al. Opioid use disorder and dementia risk: evidence from observational and genetic analyses in diverse ancestry cohorts. Alzheimer’s Dement. 2026;22:e71418. doi:10.1002/alz.71418.