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Recreational Cannabis Legalization and Opioid-Related Deaths in Colorado, 2000-2015
Melvin D Livingston1, Tracey E Barnett1, Chris Delcher1
1Melvin D. Livingston is with the Department of Biostatistics and Epidemiology, School of Public Health, University of North Texas Health Science Center, Fort Worth. Tracey E. Barnett is with the Department of Health Behavior and Health Systems, School of Public Health, University of North Texas Health Science Center. Chris Delcher is with the Department of Health Outcomes and Policy, College of Medicine, University of Florida, Gainesville. Alexander C. Wagenaar is with the Department of Behavioral Sciences and Health Education, Rollins School of Public Health, Emory University, Atlanta, GA.
Objectives:
To examine the association between Colorado's legalization of recreational cannabis use and opioid-related deaths.
Methods:
We used an interrupted time-series design (2000-2015) to compare changes in level and slope of monthly opioid-related deaths before and after Colorado stores began selling recreational cannabis. We also describe the percent change in opioid-related deaths by comparing the unadjusted model-smoothed number of deaths at the end of follow-up with the number of deaths just prior to legalization.
Results:
Colorado's legalization of recreational cannabis sales and use resulted in a 0.7 deaths per month (b = -0.68; 95% confidence interval = -1.34, -0.03) reduction in opioid-related deaths. This reduction represents a reversal of the upward trend in opioid-related deaths in Colorado.
Conclusions:
Legalization of cannabis in Colorado was associated with short-term reductions in opioid-related deaths. As additional data become available, research should replicate these analyses in other states with legal recreational cannabis.
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