Associations Between Canada's Cannabis Legalization and Emergency Department Presentations for Transient Cannabis-Induced Psychosis and Schizophrenia Conditions: Ontario and Alberta, 2015-2019.
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ABSTRACT: Objective
Cannabis legalization in many jurisdictions worldwide has raised concerns that such legislation might increase the burden of transient and persistent psychotic illnesses in society. Our study aimed to address this issue.Methods
Drawing upon emergency department (ED) presentations aggregated across Alberta and Ontario, Canada records (April 1, 2015-December 31, 2019), we employed Seasonal Autoregressive Integrated Moving Average (SARIMA) models to assess associations between Canada's cannabis legalization (via the Cannabis Act implemented on October 17, 2018) and weekly ED presentation counts of the following ICD-10-CA-defined target series of cannabis-induced psychosis (F12.5; n = 5832) and schizophrenia and related conditions ("schizophrenia"; F20-F29; n = 211,661), as well as two comparison series of amphetamine-induced psychosis (F15.5; n = 10,829) and alcohol-induced psychosis (F10.5; n = 1,884).Results
ED presentations for cannabis-induced psychosis doubled between April 2015 and December 2019. However, across all four SARIMA models, there was no evidence of significant step-function effects associated with cannabis legalization on post-legalization weekly ED counts of: (1) cannabis-induced psychosis [0.34 (95% CI -4.1; 4.8; P = 0.88)]; (2) schizophrenia [24.34 (95% CI -18.3; 67.0; P = 0.26)]; (3) alcohol-induced psychosis [0.61 (95% CI -0.6; 1.8; P = 0.31); or (4) amphetamine-induced psychosis [1.93 (95% CI -2.8; 6.7; P = 0.43)].Conclusion
Implementation of Canada's cannabis legalization framework was not associated with evidence of significant changes in cannabis-induced psychosis or schizophrenia ED presentations. Given the potentially idiosyncratic rollout of Canada's cannabis legalization, further research will be required to establish whether study results generalize to other settings.
SUBMITTER: Callaghan RC
PROVIDER: S-EPMC9301152 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:ImportanceCannabis hyperemesis syndrome is an emerging clinical issue associated with cannabis use. Legalization of cannabis has led to an increase in vomiting-related illnesses in health care settings.ObjectiveTo examine whether legalization of cannabis in Colorado has been associated with increases in vomiting-related emergency department (ED) visits.Design, setting, and participantsA cross-sectional design was used to assess the increase in ED claims for vomiting reported to the Colorado Hospital Association between January 1, 2013, and December 31, 2018, in counties that had no prior cannabis dispensaries before legalization compared with those that did. A total of 820 778 patients seeking care through Colorado EDs were included in the analysis.ExposuresThe number of medical and recreational cannabis dispensaries per county per quarter.Main outcomes and measuresCounty per capita rate of vomiting-related ED claims per quarter.ResultsVomiting-related ED health care encounters increased from 119 312 in 2013 to 153 699 in 2018 (29% increase). Over this period, 203 861 patients (25%) were aged 0 to 18 years; 114 201 (14%) were aged 19 to 25 years, and 502 771 (61%) were aged 26 years or older; 510 584 patients (62%) were female. Additional recreational dispensaries were associated with increased vomiting-related ED visits (incidence rate ratio, 1.03; 95% CI, 1.01-1.05), but counties with high baseline medical dispensary exposure experienced smaller increases in vomiting-related ED visits than counties with no baseline medical dispensary exposure (incidence rate ratio, 0.97; 95% CI, 0.95-0.99). Counties with a high number of medical marijuana dispensaries had increases at a 5.8% slower rate than counties with none.Conclusions and relevanceThe findings of this study suggest that cannabis legalization in Colorado is associated with an increase in annual vomiting-related health care encounters with regard to exposure to these markets. It may be useful for health care clinicians to be aware of cannabis hyperemesis syndrome and inquire about cannabis use when appropriate.
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Project description:ObjectivesDespite increasing rates of legalization of medical cannabis worldwide, the current evidence available on its effect on mental health outcomes including anxiety is of mixed results. This study assesses the effect of medical cannabis on generalized anxiety disorder 7-item (GAD-7) scores in adult patients between 2014 and 2019 in Ontario and Alberta, Canada.MethodsAn observational cohort study of adults authorized to use medical cannabis. The GAD-7 was administered at the time of the first visit to the clinic and subsequently over the follow-up time period of up to 3.2 years. Overall changes in GAD-7 scores were computed (mean change) and categorized as: no change (<1 point); improvement; or worsening-over time.ResultsA total of 37,303 patients had initial GAD-7 scores recorded and 5,075 (13.6%) patients had subsequent GAD-7 follow-up scores. The average age was 54.2 years (SD 15.7 years), 46.0% were male, and 45.6% noted anxiety symptoms at the baseline. Average GAD-7 scores were 9.11 (SD 6.6) at the baseline and after an average of 282 days of follow-up (SD 264) the average final GAD-7 score recorded was 9.04 (SD 6.6): mean change -0.23 (95% CI, -0.28 to -0.17, t[5,074]: -8.19, p-value <0.001). A total of 4,607 patients (90.8%) had no change in GAD-7 score from their initial to final follow-up, 188 (3.7%) had a clinically significant decrease, and 64 (1.3%) noted a clinically significant increase in their GAD-7 scores.ConclusionsOverall, there was a statistically significant decrease in GAD-7 scores over time (in particular, in the 6-12-month period). However, this change did not meet the threshold to be considered clinically significant. Thus, we did not detect clinical improvements or detriment in GAD-7 scores in medically authorized cannabis patients. However, future well-controlled clinical trials are needed to fully examine risks or benefits associated with using medical cannabis to treat anxiety conditions.
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Project description: Not available
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Project description:BACKGROUND:Collectively, the most common acute cardiac presentations to emergency departments are acute coronary syndromes (ACSs) and heart failure. We examined geographic variation and clustering in emergency department presentations by adults for ACS or heart failure in Alberta in 2010/11. METHODS:All emergency department presentations for ACS or heart failure made by Alberta residents aged 35 years or more during 2010/11 were extracted from 5 linked population-based Alberta administrative health databases. Data extracted included demographic characteristics, hospital admissions and physician claims. Spatial scan tests and logistic regression analyses were performed. RESULTS:There were 6342 patients with ACS (mean age 65.9 yr, 63.1% male) and 4780 patients with heart failure (mean age 76.6 yr, 49.9% male). For both ACS and heart failure, a primary cluster and 2 secondary clusters were identified. Different clusters were identified for the 2 conditions. For both conditions, patients living in the clusters had more primary care physician claims, prior emergency department visits and prior hospital admissions than did patients living outside the clusters. However, they were less likely to have had a specialist claim in the prior 2 years (odds ratio 0.64 [95% confidence interval 0.56-0.73] for ACS and 0.51 [95% confidence interval 0.43-0.61] for heart failure). INTERPRETATION:Geographic areas were identified with higher numbers than expected of patients presenting to the emergency department for ACS or heart failure. Lower specialist access in these areas was associated with increased emergency department use.
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Project description:BackgroundCannabis-related emergency department visits can be an entry point for youths to mental health and substance use care systems. We aimed to examine trends in cannabis-related emergency department visits as a function of youths' age and sex.MethodsUsing administrative data, we examined all visits to emergency departments in Ontario, Canada, from 2003 to 2017, by youth aged 10-24 years (grouped as 10-13, 14-18 and 19-24 yr) to determine trends in cannabis-related emergency department visits. Cannabis-related visits were identified using International Statistical Classification of Diseases and Related Health Problems, 10th Revision codes for cannabis poisoning and mental disorders due to cannabinoids. We categorized presentations as "less severe" versus "more severe" using scores assigned by nurses at triage.ResultsWe examined 14 697 778 emergency department visits. Cannabis-related visits increased from 3.8 per 10 000 youths (95% confidence interval [CI] 3.5-4.0) in 2003 to 17.9 (95% CI 17.4-18.4) in 2017, a 4.8-fold increase (95% CI 4.4-5.1). Rates increased for both sexes and each age group. Males were more likely to have a visit than females (rate ratios ≥ 1.5 in 2003 and 2017). The number of cannabis-related visits in 2017 was 25.0 per 10 000 (95% CI 24.0-25.9) among youth aged 19-24 years, 21.9 per 10 000 (95% CI 20.9-22.9) among those aged 14-18 years, and 0.8 per 10 000 (95% CI 0.5-1.0) among those aged 10-13 years. In 2017, 88.2% (95% CI 87.3%-89.0%) of cannabis-related visits and 58.1% (95% CI 58.0%-58.2%) of non-cannabis-related visits were triaged as "more severe," (rate ratio 1.52, 95% CI 1.50-1.53). Similarly, in 2017, 19.0% (95% CI 18.0%-20.1%) of cannabis-related visits and 5.8% (95% CI 5.7%-5.8%) of non-cannabis-related visits resulted in hospital admission (rate ratio 3.3, 95% CI 3.1-3.5).InterpretationRates of cannabis-related emergency department visit by youths aged 10-24 years increased almost fivefold from 2003 to 2017, with increases in visit severity and hospital admissions. These trends describe an emerging public health problem, and research is needed to identify the causes of this increase and the health and social consequences of cannabis-related visits for these youths.
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