Changes in Healthcare Encounter Rates Possibly Related to Cannabis or Alcohol following Legalization of Recreational Marijuana in a Safety-Net Hospital: An Interrupted Time Series Analysis.

Authors:
Susan L Calcaterra
Susan L Calcaterra
University of Colorado Denver
United States
Christian J Hopfer
Christian J Hopfer
Institute for Behavioral Genetics
United States
Angela Keniston
Angela Keniston
Division of Hospital Medicine
United States

J Addict Med 2018 Nov 20. Epub 2018 Nov 20.

Department of Medicine, Division of Hospital Medicine, Denver Health Medical Center, Denver (SLC, AK, MLH); Department of Medicine, Division of General Internal Medicine (SLC); Department of Family Medicine (SLC); Department of Psychiatry (CJH); Department of Medicine, Division of Hospital Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO (AK).

Objectives: Liberalization of marijuana laws in Colorado contributed to increases in cannabis-related adverse events over time. We examined characteristics of patients with healthcare encounters possibly related to cannabis and assessed the temporal association between legalization of recreational marijuana and healthcare encounters possibly attributed to cannabis.

Methods: Annual encounter rates possibly related to cannabis and alcohol were compared using negative binomial regression. Two-time intervals, pre/post-recreational marijuana legalization (January 2009 to December 2013 and January 2014 to December 2015, respectively) were used to examine changes in monthly rates of emergency encounters and hospitalizations possibly related to cannabis. Level and trend changes on encounter rates by legalization period were assessed using interrupted time series analyses. Encounters possibly related to alcohol were used as a comparator group.

Results: Most encounters identified during the study period had alcohol-related International Classification of Diseases Diagnosis and Procedural Codes (ICD-9/10-CM) codes (94.8% vs 5.2% for cannabis). Patients with encounters possibly related to cannabis were younger, more likely to be hospitalized and more likely to be admitted to the psychiatric unit than patients with encounters possibly related to alcohol. Initial and sustained effects of encounter rates possibly related to cannabis demonstrated an increased trend in slope before and after recreational marijuana legalization. The slope became more abrupt following legalization with a significant increase in trend during the post-legalization period (β = 2.7, standard error = 0.3, ρ < 0.0001). No significant change was noted for encounters possibly related to alcohol.

Conclusions: Additional research should identify patients at highest risk of an adverse health event related to cannabis and quantify costs associated with cannabis-related healthcare delivery.

Download full-text PDF

Source
http://dx.doi.org/10.1097/ADM.0000000000000480DOI Listing

Still can't find the full text of the article?

We can help you send a request to the authors directly.
November 2018
27 Reads

Publication Analysis

Top Keywords

encounter rates
16
recreational marijuana
12
rates cannabis
12
cannabis alcohol
8
marijuana legalization
8
legalization recreational
8
patients encounters
8
healthcare encounters
8
encounters alcohol
8
encounters cannabis
8
interrupted time
8
time series
8
encounters
7
cannabis
7
legalization
6
marijuana
5
rates
5
encounters hospitalizations
4
hospitalizations cannabis
4
2015 examine
4

Similar Publications