States with medical cannabis laws had significantly lower opioid prescription rates among privately insured adults under 55, but not among those 55-64, and recreational cannabis or decriminalization laws showed no association.
Policymakers, pain management clinicians, and researchers studying the opioid-cannabis relationship.
44% lower opioid prescriptions in 18-25 year-olds in medical cannabis states
What the researchers found
In states with medical cannabis laws, opioid prescription rates (>30-day and >90-day) were significantly lower for adults aged 18-54 (aORs ranging from 0.56 to 0.77). The association was not significant for ages 55-64. Recreational use and decriminalization laws showed no significant association with opioid prescriptions in any age group.
Why it matters
The opioid crisis has driven interest in whether cannabis access could reduce opioid dependence. This study provides evidence that medical cannabis laws specifically (not recreational or decriminalization) are associated with lower opioid prescribing in younger adults.
The numbers in context
Medical cannabis states: >30-day opioid aOR = 0.56 (ages 18-25), 0.67 (26-35), 0.67 (36-45), 0.76 (46-54). All p < 0.0001. Not significant for ages 55-64. No association with recreational or decriminalization laws.
How the study worked
Cross-sectional analysis of the 2016 Clinformatics Data Mart, a nationwide commercial insurance database. Multilevel multivariable analysis compared opioid prescribing patterns across states with different cannabis law stringencies, stratified by five age groups.
What this study cannot tell us
Cross-sectional design; cannot establish causation. Only privately insured adults included. State-level confounders (pain management culture, prescribing policies) could explain differences. Cannabis use itself was not measured.
How to read the evidence
Moderate: large nationwide insurance database with multilevel analysis, but cross-sectional and ecological design.
When this study was published
Published in 2019.
The bigger picture
The finding that only medical cannabis laws (not recreational or decriminalization) showed an association suggests something specific about the medical framework matters, possibly clinical involvement or insurance coverage.
Questions still open
- Why did the association disappear in adults 55-64? Are older adults less likely to substitute cannabis for opioids? Would similar patterns emerge in Medicaid or Medicare populations?
Common questions
Does this mean cannabis replaces opioids?
Why only medical cannabis and not recreational?
Read the original research
Association between cannabis laws and opioid prescriptions among privately insured adults in the US.
Preventive medicine, 125, 62-68
Citation
Raji, Mukaila A; Abara, N Ogechi; Salameh, Habeeb; Westra, Jordan R; Kuo, Yong-Fang. (2019). Association between cannabis laws and opioid prescriptions among privately insured adults in the US.. Preventive medicine, 125, 62-68. https://doi.org/10.1016/j.ypmed.2019.05.012