HealthDay News — For U.S. adults with problem substance use who use nonmedical opioids, the odds of opioid use are increased on days when cannabis is used, according to a study published online Oct. 8 in Addiction.
Lauren R. Gorfinkel, M.P.H., from Columbia University in New York City, and colleagues conducted a prospective cohort study involving adults with problem substance use who use nonmedical opioids recruited from May 2016 to June 2019. A total of 13,271 days of observation were included for 211 participants. Interviewer- and self-administered computerized surveys were completed, and participants responded to an interactive voice response system to assess cannabis use, nonmedical or illicit opioid use, and pain for the following 90 days.
The researchers found that the unadjusted odds ratio was 2.00 for opioid use on days with cannabis use relative to opioid use on days without cannabis use. The adjusted odds ratio was 1.86 after controlling for demographic characteristics, recruitment method, opioid types at baseline, and pain. Inconclusive results were seen in a test of interaction between pain and cannabis use.
“Our study is among the first to test opioid substitution directly, suggesting that cannabis seldom serves as a substitute for nonmedical opioids among opioid-using adults, even among those who report experiencing moderate or more severe pain. In other words, our study suggests that cannabis is not an effective way to limit nonmedical opioid use,” one coauthor said in a statement.