Study muddies the water on cannabis / opioid use

Contrary to some claims, people in the U.S may not be substituting cannabis for opioids, according to new research at Columbia University Mailman School of Public Health.

The study examined the direction and strength of association between cannabis and opioid use over 90 consecutive days among adults who used non-medical opioids.

The findings showed that opioid use was at least as prevalent on days when cannabis was used as on days when it was not, and that this was irrespective whether participants were experiencing pain or not. The study, published in the scientific journal Addiction, is among the first to test opioid substitution directly.

The study, which compared the probability of non-medical opioid use on days when cannabis was used with days when cannabis was not used, included 13,271 days of observation among 211 participants from the greater New York area.

The participants were predominantly male, urban, unemployed, unmarried, and had a high prevalence of substance misuse and pain.

“Our results suggest that cannabis seldom serves as a substitute for non-medical opioids among opioid-using adults, even among those who report experiencing moderate or more severe pain,” said Deborah Hasin, professor of epidemiology at Columbia Mailman School and a professor in the Department of Psychiatry at Columbia University Irving Medical Center.

“In other words, our study suggests that cannabis is not an effective way to limit non-medical opioid use.”

In 2017, there were over 2 million people with opioid use disorder and over 70,000 opioid-related deaths in the US. Illicit opioid use, including non-medical use of prescription opioids, synthetic opioids and heroin, are the primary cause of overdose deaths among U.S. adults. Understanding how cannabis may change non-medical opioid use is critical to informing discussions around cannabis-based interventions for addressing the opioid crisis.