State cannabis legalization accounted for a modest but significant portion of increasing CUD prevalence among VA patients, with the greatest impact on adults aged 65-75.
VA clinicians, addiction medicine specialists, and cannabis legalization researchers.
18.6% attributable to RCLof CUD prevalence increase among VA patients aged 65-75 in recreational cannabis law states
What the researchers found
MCL-only enactment accounted for 4.7% of CUD increases, while RCL enactment accounted for 9.8%. The effect was strongest in patients 65-75 years old, where RCL accounted for 18.6% of CUD prevalence increases.
Why it matters
While cannabis legalization plays a role in rising CUD rates, the relatively small effect sizes suggest other factors (changing attitudes, commercialization) are equally or more important.
The numbers in context
CUD prevalence: no-CL states 1.38% to 2.25%, MCL-only states 1.38% to 2.54%, RCL states 1.39% to 2.56% (2005-2019). RCL in ages 65-75: 0.15% absolute increase, 18.6% of total increase attributable.
How the study worked
Staggered-adoption difference-in-difference analysis of VHA electronic health records (2005-2019) with fixed effects for state, year, and demographics.
Who was studied
VHA patients aged 18-75 (3.2M in 2005 to 4.6M in 2019), largely male (94.1% in 2005, 89.0% in 2019).
What this study cannot tell us
VHA patients are predominantly male. CUD diagnoses depend on clinical screening practices. Effect sizes are small in absolute terms. Cannot capture undiagnosed CUD.
How to read the evidence
Large quasi-experimental study with robust difference-in-difference design from VHA records.
When this study was published
Covers 15 years of national VHA data (2005-2019).
The bigger picture
CUD is increasing across the U.S. regardless of cannabis law status, suggesting that legalization accelerates rather than initiates the trend. The outsized effect on older patients warrants particular clinical attention.
Replication
Companion to RTHC-04612 and RTHC-04614; consistent findings across related analyses.
Funding
Not specified in abstract
Conflicts of interest
Not specified in abstract
Questions still open
- What factors beyond legalization are driving the nationwide increase in CUD?
- Should CUD screening be intensified for older VA patients in legalized states?
Read the original research
State Cannabis Legalization and Cannabis Use Disorder in the US Veterans Health Administration, 2005 to 2019.
JAMA psychiatry, 80(4), 380-388
Citation
Hasin, Deborah S; Wall, Melanie M; Choi, C Jean; Alschuler, Daniel M; Malte, Carol; Olfson, Mark; Keyes, Katherine M; Gradus, Jaimie L; Cerdá, Magdalena; Maynard, Charles C; Keyhani, Salomeh; Martins, Silvia S; Fink, David S; Livne, Ofir; Mannes, Zachary; Sherman, Scott; Saxon, Andrew J. (2023). State Cannabis Legalization and Cannabis Use Disorder in the US Veterans Health Administration, 2005 to 2019.. JAMA psychiatry, 80(4), 380-388. https://doi.org/10.1001/jamapsychiatry.2023.0019