New study finds link between legalized marijuana and reduced opioid deaths

Posted Date: October 12, 2017

Lead author Melvin D. Livingston, PhD, with Tracey E. Barnett, PhD

UNT Health Science Center researchers and colleagues have released findings from a new study, published in the American Journal of Public Health, showing a reduction in opioid-related deaths following legalized recreational marijuana in Colorado.

Illegal and legally prescribed opioids now account for nearly 30,000 deaths a year in the United States, and the CDC says that 91 Americans die every day from an opioid overdose.

CDC data shows that opioid deaths from prescription drugs, heroin and synthetics like fentanyl have more than quadrupled since 1999.

In a July 31, 2017, interim report to the White House, the U.S. Commission on Combating Drug Addiction and the Opioid Crisis emphasized the severity of the problem, calling America “a nation in crisis.”

“As policy makers continue to grapple with both the growing opioid crisis and the rapidly changing landscape of marijuana laws in the U.S., scientific evidence is needed to help inform policy decisions to combat this disturbing upward trend in opioid-related deaths,” said Melvin D. Livingston, PhD, lead author of the study.

The researchers analyzed Colorado data covering a 15-year period from 2000 to 2015 to compare changes in the number of opioid-related deaths before and after recreational marijuana sale and use was legalized.

Findings showed that opioid deaths fell more than 6 percent in the following two years after the state’s marijuana legalization, reversing the previous upward trend.

“As of 2016, eight states and Washington DC have legalized recreational marijuana. While we found an apparent public health benefit in short-term reduction of opioid-related deaths following Colorado’s legalization, it’s important to note that expanded, legalized marijuana can also be associated with significant potential harms,” Dr. Livingston said.

“For policymakers to weigh decisions balancing potential beneficial and detrimental effects of these laws, researchers must continue to examine the full range of health outcomes through further study,” he said.

Dr. Livingston is Assistant Professor of Biostatistics and Epidemiology at the UNTHSC School of Public Health.

Co-authors of the study were Tracey E. Barnett, PhD, Associate Professor and Associate Dean for Academic Affairs, also with the UNTHSC School of Public Health; Chris Delcher, PhD, from the University of Florida; and Alex C. Wagenaar, PhD, from Emory University.