Adolescent cannabis hospitalizations increased after legalization, especially in recreational states

Among nearly 1.9 million adolescent hospitalizations across 18 states from 2008-2019, cannabis-related admissions increased after both medical and recreational legalization, with the steepest increases in recreational states and among younger teens.

Masonbrink, Abbey R et al.·The Journal of adolescent health : official publication of the Society for Adolescent Medicine·2021·Strong EvidenceRetrospective Cohort
RTHC-03328Retrospective CohortStrong Evidence2021RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Retrospective Cohort
Evidence
Strong Evidence
Sample
Not reported

What This Study Found

Cannabis-related hospitalization odds increased after both medical cannabis laws (OR 1.05) and recreational cannabis laws (OR 1.03). The greatest increases post-legalization were in adolescents without underlying mental health or substance use disorders and in younger adolescents (age 13) in recreational states.

Key Numbers

1,898,432 hospitalizations; 37,562 (2%) cannabis-related; MCL states OR 1.05; NMCL states OR 1.03; greatest increases in adolescents without mental health disorders and age 13 in NMCL states

How They Did This

Retrospective cohort study of 1,898,432 adolescent (11-17 years) hospitalizations at children's hospitals from 2008-2019 using the Inpatient Essentials database across 18 states and Washington, DC. Logistic regression compared cannabis-related diagnoses by state legalization status.

Why This Research Matters

Legalization policies for adults (21+) may have downstream effects on adolescent health. The finding that younger teens and those without pre-existing mental health conditions showed the greatest post-legalization increases suggests legalization may be expanding cannabis-related hospitalizations beyond traditional high-risk groups.

The Bigger Picture

While the absolute odds ratios are small, the shift toward younger adolescents and those without pre-existing conditions after recreational legalization suggests these policies may be normalizing cannabis use in ways that reach vulnerable populations not previously at risk.

What This Study Doesn't Tell Us

Hospital-based data may miss cases managed in outpatient settings. Cannabis-related diagnosis coding may vary across institutions and time. Cannot determine whether increases reflect more use or more screening/documentation. Administrative data lacks use pattern details.

Questions This Raises

  • ?Are the increases driven by actual increased use or improved detection?
  • ?What specific harms are driving these hospitalizations?
  • ?Would targeted prevention in recreational states reduce these trends?
  • ?How do these patterns evolve as legalization matures?

Trust & Context

Key Stat:
Greatest increase in 13-year-olds in recreational legalization states
Evidence Grade:
Large multi-state hospital database with longitudinal tracking across policy changes, though administrative data limitations apply.
Study Age:
Published in 2021 using data from 2008-2019.
Original Title:
Trends in Adolescent Cannabis-Related Hospitalizations by State Legalization Laws, 2008-2019.
Published In:
The Journal of adolescent health : official publication of the Society for Adolescent Medicine, 69(6), 999-1005 (2021)
Database ID:
RTHC-03328

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-ControlFollows or compares groups over time
This study
Cross-Sectional / Observational
Case Report / Animal Study

Looks back at existing records to find patterns.

What do these levels mean? →

Frequently Asked Questions

Did legalization increase teen hospitalizations for cannabis?

Yes, modestly. Both medical and recreational legalization were associated with small but significant increases in cannabis-related adolescent hospitalizations, with recreational states showing a disproportionate increase.

Which teens were most affected?

The greatest post-legalization increases were in younger adolescents (age 13) and those without pre-existing mental health or substance use disorders, suggesting legalization may be reaching new populations.

Read More on RethinkTHC

Cite This Study

RTHC-03328·https://rethinkthc.com/research/RTHC-03328

APA

Masonbrink, Abbey R; Richardson, Troy; Hall, Matt; Catley, Delwyn; Wilson, Karen. (2021). Trends in Adolescent Cannabis-Related Hospitalizations by State Legalization Laws, 2008-2019.. The Journal of adolescent health : official publication of the Society for Adolescent Medicine, 69(6), 999-1005. https://doi.org/10.1016/j.jadohealth.2021.07.028

MLA

Masonbrink, Abbey R, et al. "Trends in Adolescent Cannabis-Related Hospitalizations by State Legalization Laws, 2008-2019.." The Journal of adolescent health : official publication of the Society for Adolescent Medicine, 2021. https://doi.org/10.1016/j.jadohealth.2021.07.028

RethinkTHC

RethinkTHC Research Database. "Trends in Adolescent Cannabis-Related Hospitalizations by St..." RTHC-03328. Retrieved from https://rethinkthc.com/research/masonbrink-2021-trends-in-adolescent-cannabisrelated

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.