Colorado Cannabis Legalization and Its Effect on Emergency Care

Exploring Cannabis-Associated Presentations to Canadian Pediatric Emergency Departments: A Cross-Sectional Study

Objective

Recent studies found that recreational legalization of cannabis consumption for Canadian adults has increased presentation to the emergency department (ED) among children. In this descriptive study, our objectives were to (1) understand Canadian pediatric emergency medicine (PEM) providers' training and knowledge of clinical presentations associated with cannabis exposure in children and (2) describe pediatric ED presentations related to cannabis exposure across Canada following legalization in 2018.

Method

In 2021, following ethics board approval, 230 Pediatric Emergency Research Canada (PERC) network pediatric emergency medicine (PEM) physicians were invited to share about their knowledge, training, and experience with patients presenting with cannabis-associated emergencies using an anonymized survey administered through REDCap.

Results

In total, 84/230 (36.5%) invited physicians completed the survey. Almost 70% of the PEM physicians reported an increase in the number of cannabis-associated ED presentations they have seen since legalization, while only 15% reported no increase in presentations. More than 90% of the respondents reported an average or higher level of knowledge of cannabis-associated pediatric emergencies. More than half (n = 48, 57%) were interested in pursuing further training, preferring formal training opportunities. The main presentations to the ED were decreased level of consciousness, known unintentional (accidental) ingestion and vomiting. Significantly more tests were ordered when cannabis consumption was unknown at the beginning of the assessment, compared to when it was known, however, treatment plans were the same (mainly supportive measures).

Conclusions

Most PEM providers are managing an increasing number of cannabis-associated ED presentations. PEM providers should improve communication with caregivers around household cannabis use. When caregivers feel comfortable disclosing cannabis presence at home, it can help prevent unnecessary tests and interventions for their children if they present to the ED.

Sociodemographic profile and clinical presentation of young children unintentionally exposed to marijuana: A single site retrospective cohort

BACKGROUND AND OBJECTIVES

Legalization of medical marijuana has increased unintentional exposure to marijuana in young children. We aim to explore the sociodemographic disadvantage profile, prevalence, and clinical presentation of children diagnosed with unintentional exposure to marijuana.

METHODS

We conducted a retrospective chart abstraction of 121 children (aged 0-6) seen at the Emergency Department (ED) at a single tertiary hospital center in Dayton, Ohio between January 01, 2010 and January 09, 2022.

RESULTS

Majority were female (62.8%), white (50.4%), and with Medicaid as their primary insurance (84.3%). The median age at exposure was 1.8 years. There was a 14-fold increase in unintentional marijuana cases pre-2017 (7 cases) versus post-2017 (114 cases), the year of legalization of medical marijuana in the state of Ohio. Majority of the patients were using public assistance (66.4%). 26.7% of the cases had a prior social work consultation and 38.1% had a prior children services consultation. 51.3% of the children had a social disadvantage index score of 3 or greater (range 0-5) with higher scores indicating greater disadvantage.

DISCUSSION AND CONCLUSIONS

The number of patients presenting to the ED at the hospital has increased 14-fold since the legalization of medical marijuana in Ohio. Half of the children displayed a higher sociodemographic disadvantage index score.

SCIENTIFIC SIGNIFICANCE

Our study is the first study investigating the sociodemographic profile of children exposed to marijuana. The findings of this study may be utilized to inform policy for safely dispensing recreational and medicinal marijuana products and focus the efforts on families with sociodemographic disadvantage.

The impact of recreational cannabis legalization on ED visit rates for acute cannabis intoxication

BACKGROUND

In December 2018 the Michigan Regulation and Taxation of Marihuana Act legalized the recreational use of cannabis in Michigan. There are now high potency forms of cannabis readily available in the state, which could result in increased emergency department (ED) visit rates due to intoxication in adults and children. Although cannabis related visits account for a small percentage of all adult and pediatric ED visits, they impose a significant burden on the health care system's resources. This study aimed to assess the impact of the legalization of recreational marijuana on the rate of ED visits for acute cannabis intoxication.

METHODS AND DESIGN

We utilized the legalization of marijuana in the state of Michigan to conduct a natural experiment utilizing a retrospective observational cohort design of ED visits for acute intoxication before and after legalization. The study was conducted at a health system composed of eight hospitals in southeast Michigan, including both academic and community hospitals serving a diverse patient population. We estimated monthly cannabis-related ED visits based on cannabis-related ICD-10 discharge codes and total ED visits using electronic health record data from 2016 to 2022. A negative-binomial (NB) regression model was used to estimate the immediate and cumulative changes in cannabis-related ED visit rate after legalization.

RESULTS

There were a total of 2177 ED visits from 2066 patients for cannabis intoxication in our study cohort. Of the 2177 visits, 671 were before and 1506 were after legalization. In the univariate analysis, recreational cannabis legalization was associated with an increase in the average cannabis-related ED visit rate (Rate Ratio [RR]:1.70, 95% CI: (1.49, 1.94), p-value <0.001). In the multivariate analysis adjusting for age, results remain significant (RR 1.47, 95% CI (1.29, 1.70), p-value <0.001). The increased visit rate occurred in the first month after legalization; however, the slope of the increasing rate of ED visits were similar before and after cannabis legalization (RR, 1.28, 95% CI (1.07, 1.54), p-value <0.001).

CONCLUSIONS

The legalization of recreational cannabis in Michigan was associated with an immediate increase in ED visit rates for acute cannabis intoxications across all ages, especially among middle-aged adults, in the context of an stably increasing ED visit rate.

Clinician perspectives on adolescent cannabis-related beliefs and behaviors following recreational cannabis legalization

BACKGROUND

As more states legalize cannabis, studies are needed to understand the potential impacts of recreational cannabis legalization (RCL) on adolescents from the perspective of clinicians who care for them.

METHODS

This qualitative study characterized clinician perspectives on whether cannabis legalization is associated with changes in adolescents' cannabis use beliefs, behaviors, and consequences. Semi-structured qualitative interviews were conducted with 32 clinicians in a large healthcare organization from 9/6/2022-12/21/2022. Video-recorded interviews were transcribed and analyzed using thematic analysis.

RESULTS

The 32 participants (56.3 % female, mean [SD] age, 45.9 [7.6] years; 65.3 % non-Hispanic White) were from Addiction Medicine (n = 13), Psychiatry/Mental Health (n = 7), Pediatrics (n = 5), and the Emergency Department (n = 7). Clinicians described post-RCL increases in adolescent cannabis use, use of non-combustible modes and high-potency products, and younger age of first use. Clinicians reported social, physical, and policy changes, including changes in social norms, appealing advertisements, marketing, and easier access. Many noted fewer perceived harms among adolescents and greater self-medication post-RCL. They described how RCL contributed to increased parental cannabis use and permissiveness around adolescent use. Finally, many described post-RCL increases in cannabis hyperemesis syndrome, and several noted increased cannabis-related psychosis and acute intoxication, and decreased court-mandated treatment.

CONCLUSIONS

Clinicians from diverse specialties described post-RCL increases in adolescent cannabis use and cannabis-related consequences, alongside changes in social norms, access, marketing and advertisements, and decreased perceptions of harms. Findings can inform strategies to support adolescents in the context of increased cannabis availability and acceptability post-legalization and support the development of hypotheses for broader-scale quantitative work.

Trends in cannabis use in New Jersey: Effects of COVID-19 and cannabis legalization

Objectives

With the legalization of cannabis in New Jersey on April 21, 2022, including the licensing of cannabis dispensaries, concerns have arisen about potential adverse events related to cannabis use. Here, we explore temporal trends and risk factors for cannabis-related harm in both adult and pediatric cannabis-related visits at a tertiary care academic institution.

Methods

We performed a retrospective chart review and temporal trend analysis via the electronic health record from May 1, 2019 to October 31, 2022, covering 2 years before, and 6 months after, cannabis legalization in New Jersey. The pediatric charts identified were analyzed for root causes of adverse events, and changes in the frequency of specific unsafe practices since cannabis legalization were tracked.

Results

We found that adult cannabis ED-related visits significantly increased during the COVID-19 pandemic and remained higher than pre-pandemic levels for the remainder of the study periods, without a significant change upon legalization. Pediatric rates of cannabis-related ED visits did not vary significantly during the study period. The vast majority of visits for children aged 0-12 years were related to accidental cannabis exposures-often a household member's edibles-whereas most visits for older children stemmed from intentional cannabis use.

Conclusion

This project highlights the unintended consequences of wider cannabis access in New Jersey. Notably, cannabis use increased even before its legalization, presumably in response to the COVID-19 pandemic and its attendant mental health effects. Rates of cannabis use disorder and its highlight of other concurrent psychiatric disorders are important topics for both clinicians and lawmakers to consider.

Trends of emergency department visits for cannabinoid hyperemesis syndrome in Nevada: An interrupted time series analysis

Cannabis-related emergency department visits have increased after legalization of cannabis for medical and recreational use. Accordingly, the incidence of emergency department visits due to cannabinoid hyperemesis syndrome in patients with chronic cannabis use has also increased. The aim of this study was to examine trends of emergency department visit due to cannabinoid hyperemesis syndrome in Nevada and evaluate factors associated with the increased risk for emergency department visit. The State Emergency Department Databases of Nevada between 2013 and 2021 were used for investigating trends of emergency department visits for cannabinoid hyperemesis syndrome. We compared patients visiting the emergency department due to cannabinoid hyperemesis syndrome with those visiting the emergency department due to other causes except cannabinoid hyperemesis and estimated the impact of cannabis commercialization for recreational use. Emergency department visits due to cannabinoid hyperemesis syndrome have continuously increased during the study period. The number of emergency department visits per 100,000 was 1.07 before commercialization for recreational use. It increased to 2.22 per 100,000 (by approximately 1.1 per 100,000) after commercialization in the third quarter of 2017. Those with cannabinoid hyperemesis syndrome were younger with fewer male patients than those without cannabinoid hyperemesis syndrome. A substantial increase in emergency department visits due to cannabinoid hyperemesis syndrome occurred in Nevada, especially after the commercialization of recreational cannabis. Further study is needed to explore factors associated with emergency department visits.

Perceptions and engagement of patients with chronic conditions on the use of medical cannabis: a scoping review

CONTEXT

Studies generally focus on one type of chronic condition and the effect of medical cannabis (MC) on symptoms; little is known about the perceptions and engagement of patients living with chronic conditions regarding the use of MC.

OBJECTIVES

This scoping review aims to explore: (1) what are the dimensions addressed in studies on MC that deal with patients' perceptions of MC? and (2) how have patients been engaged in developing these studies and their methodologies? Through these objectives, we have identified areas for improving future research.

METHODS

We searched five databases and applied exclusion criteria to select relevant articles. A thematic analysis approach was used to identify the main themes: (1) reasons to use, to stop using or not to use MC, (2) effects of MC on patients themselves and empowerment, (3) perspective and knowledge about MC, and (4) discussion with relatives and healthcare professionals.

RESULTS

Of 53 articles, the main interest when assessing the perceptions of MC is to identify the reasons to use MC (n = 39), while few articles focused on the reasons leading to stop using MC (n = 13). The majority (85%) appraise the effects of MC as perceived by patients. Less than one third assessed patients' sense of empowerment. Articles determining the beliefs surrounding and knowledge of MC (n = 41) generally addressed the concerns about or the comfort level with respect to using MC. Only six articles assessed patients' stereotypes regarding cannabis. Concerns about stigma constituted the main topic while assessing relationships with relatives. Some articles included patients in the research, but none of them had co-created the data collection tool with patients.

CONCLUSIONS

Our review outlined that few studies considered chronic diseases as a whole and that few patients are involved in the co-construction of data collection tools as well. There is an evidence gap concerning the results in terms of methodological quality when engaging patients in their design. Future research should evaluate why cannabis' effectiveness varies between patients, and how access affects the decision to use or not to use MC, particularly regarding the relationship between patients and healthcare providers. Future research should consider age and gender while assessing perceptions and should take into consideration the legislation status of cannabis as these factors could in fact shape perception. To reduce stigma and stereotypes about MC users, better quality and accessible information on MC should be disseminated.

The impact of recreational cannabis laws on cannabis use disorder during "treat and release" visits to hospital emergency departments in four U.S. states, 2017-2020

States' legalization of cannabis influences cannabis use and may increase cannabis use disorder (CUD)-a problematic pattern of use leading to significant impairment. Few studies have examined the influence of recreational cannabis legalization on CUD in the emergency department (ED). We used four years of data from the State Emergency Department Databases (SEDD) (2017-2020) from three states (CO, MD, OR) and three years of SEDD from Rhode Island (2017-2019) to examine the relationship between the recreational legalization of cannabis and CUD among "treat and release" ED visits. During the study period, CO and OR were legal for recreational cannabis while it was illegal in MD and RI. We examined the proportion of ED visits for CUD and used multivariate logistic regression to examine the association between recreational legalization and CUD diagnosis. The sample had 17,434,655 ED visits (56.2 % female). The proportion of ED visits for CUD was 0.63 %. Annual rates ranged from 0.67 % (2017) to 0.59 % (2019) and state-level rates were 0.39 % (CO), 0.35 % (OR), 1.03 % (MD), and 0.79 % (RI). Compared to ED visits in legal states, a higher proportion of ED visits in non-legal states were from women (56.8 % versus 55.7 %) and Blacks (40.9 % versus 5.9 %). Compared to states where recreational cannabis was illegal, legalizing cannabis for recreational use was associated with nearly a 50 % decrease in the adjusted odds of CUD (AOR = 0.49, 95 % CI 0.47, 0.52). In summary, CUD rates among "treat and release" ED visits were significantly lower in legalized states than in non-legal states.

Cannabinoid hyperemesis syndrome in pregnancy: Challenges and opportunities

Antenatal cannabis consumption is common and associated with adverse perinatal outcomes, including low birthweight, pre-term birth and increased rates of admission to neonatal intensive care. Cannabinoid hyperemesis syndrome (CHS) comprises severe, cyclical episodes of vomiting, intractable nausea and abdominal pain observed in chronic cannabis users. CHS, particularly during pregnancy, poses a diagnostic dilemma with a tendency to be ineffectively managed secondary to reduced clinician awareness and a scarcity of available therapies. This clinical perspective explores the current literature on CHS in pregnancy, available pharmacotherapeutics, and recognises the current barriers to improving clinical care.

Health, safety, and socioeconomic impacts of cannabis liberalization laws: An evidence and gap map

Background

Globally, cannabis laws and regulations are rapidly changing. Countries are increasingly permitting access to cannabis under various decriminalization, medicalization, and legalization laws. With strong economic, public health, and social justice incentives driving these domestic cannabis policy reforms, liberalization trends are bound to continue. However, despite a large and growing body of interdisciplinary research addressing the policy-relevant health, safety, and socioeconomic consequences of cannabis liberalization, there is a lack of robust primary and systematic research that comprehensively investigates the consequences of these reforms.

Objectives

This evidence and gap map (EGM) summarizes the empirical evidence on cannabis liberalization policies. Primary objectives were to develop a conceptual framework linking cannabis liberalization policies to relevant outcomes, descriptively summarize the empirical evidence, and identify areas of evidence concentration and gaps.

Search Methods

We comprehensively searched for eligible English-language empirical studies published across 23 academic databases and 11 gray literature sources through August 2020. Additions to the pool of potentially eligible studies from supplemental sources were made through November 2020.

Selection Criteria

The conceptual framework for this EGM draws upon a legal epidemiological perspective highlighting the causal effects of law and policy on population-level outcomes. Eligible interventions include policies that create or expand access to a legal or decriminalized supply of cannabis: comprehensive medical cannabis laws (MCLs), limited medical cannabidiol laws (CBDLs), recreational cannabis laws (RCLs), industrial hemp laws (IHLs), and decriminalization of cultivations laws (DCLs). Eligible outcomes include intermediate responses (i.e., attitudes/behaviors and markets/environments) and longer-term consequences (health, safety, and socioeconomic outcomes) of these laws.

Data Collection and Analysis

Both dual screening and dual data extraction were performed with third person deconfliction. Primary studies were appraised using the Maryland Scientific Methods Scale and systematic reviews were assessed using AMSTAR 2.

Main Results

The EGM includes 447 studies, comprising 438 primary studies and nine systematic reviews. Most research derives from the United States, with little research from other countries. By far, most cannabis liberalization research focuses on the effects of MCLs and RCLs. Studies targeting other laws-including CBDLs, IHLs, and DCLs-are relatively rare. Of the 113 distinct outcomes we documented, cannabis use was the single most frequently investigated. More than half these outcomes were addressed by three or fewer studies, highlighting substantial evidence gaps in the literature. The systematic evidence base is relatively small, comprising just seven completed reviews on cannabis use (3), opioid-related harms (3), and alcohol-related outcomes (1). Moreover, we have limited confidence in the reviews, as five were appraised as minimal quality and two as low quality.

Authors’ Conclusions

More primary and systematic research is needed to better understand the effects of cannabis liberalization laws on longer-term-and arguably more salient-health, safety, and socioeconomic outcomes. Since most research concerns MCLs and RCLs, there is a critical need for research on the societal impacts of industrial hemp production, medical CBD products, and decriminalized cannabis cultivation. Future research should also prioritize understanding the heterogeneous effects of these laws given differences in specific provisions and implementation across jurisdictions.

Perceptions and Practices of Cannabis Use Among Emergency Department Patients

BACKGROUND

Nationally, in states where cannabis has been legalized, increases in cannabis-related hospitalizations and emergency department (ED) visits have also been observed.

OBJECTIVES

This study aims to: 1) Describe the sociodemographic characteristics of cannabis users presenting to two academic EDs in California; 2) Assess cannabis-related behaviors; 3) Assess perceptions of cannabis; 4) Identify and describe reasons for cannabis-related ED utilization.

METHODS

This is a cross-sectional study of patients visiting one of two academic EDs between February 16, 2018 and November 21, 2020. Eligible participants completed a novel questionnaire developed by the authors. Basic descriptive statistics, Pearson correlation coefficients, and logistic regression were used for statistical analysis of responses.

RESULTS

The questionnaire was completed by 2577 patients. A quarter were categorized as Current Users (n = 628, 24.4%). Current, Regular Users were evenly divided across gender, were relatively younger (18-34 years, 48.1%), and were largely non-Hispanic Caucasian. Over half of all respondents believed that the use of cannabis was less harmful than tobacco or alcohol use (n = 1537, 59.6%). One in five Current Users (n = 123, 19.8%) reported driving while using cannabis in the past month. A small proportion (n = 24, 3.9%) of Current Users reported ever visiting the ED for a cannabis-related chief complaint.

CONCLUSIONS

Overall, many ED patients are currently using cannabis; few report utilizing the ED due to cannabis-related problems. Current, Irregular Users may represent the ideal target group for ED-based educational efforts aimed at improving knowledge of safe cannabis use.

Chronic health conditions, acute health events, and healthcare utilization among adults over age 50 in Hawai'i who use cannabis: A matched cohort study

BACKGROUND

Research on cannabis-related health outcomes in diverse older adults is limited. The current study utilized a matched cohort study design to compare older adults in Hawai'i with identified cannabis diagnoses and matched controls on chronic health conditions, acute health events, and healthcare utilization from 2016 to 2020.

METHOD

Patients age 50 + were identified using ICD-10 diagnostic codes for cannabis use, abuse, and dependence using electronic health record data from an integrated health system (Kaiser Permanente Hawai'i). Those with cannabis diagnoses (n = 275) were compared to matched non-using controls (n = 275; based on age, sex) on chronic health conditions (coronary heart disease, hypertension, COPD, chronic non-cancer pain), acute health events (myocardial infarction, respiratory symptoms, stroke, persistent or cyclic vomiting, injuries), and healthcare utilization (outpatient, inpatient, and emergency department visits) following case identification for two years.

RESULTS

Participants were 19.3% Native Hawaiian/Pacific Islander, 24.4% Asian, 47.8% White, and 8.5% Other/Unknown, with an average age of 62.8 years (SD=7.3). Adjusting for covariates as possible, participants with a cannabis diagnosis had significantly greater risk of coronary heart disease, chronic non-cancer pain, stroke, myocardial infarction, cyclic vomiting, and injuries, over time, compared to controls. Cannabis use was associated with any and greater frequency of outpatient, inpatient, and emergency department visits.

CONCLUSIONS

In a diverse sample, older adults who used cannabis had worse health conditions and events and used more health services over a two-year period. Future studies should evaluate cannabis-related health outcomes, effects of cannabis problem severity, as well as implications for healthcare in aging populations.

Retail cannabis environment and adolescent use: The role of advertising and retailers near home and school

Youth cannabis use is influenced by overlapping environmental contexts. We examined the associations between proximity to cannabis retailers and seeing cannabis advertisements and cannabis use behaviors in Oregon, a state with adult cannabis legalization. We used 2017 anonymous survey data from 24,154 Oregon 8th and 11th grade students. After adjustments for student and school district characteristics, advertising for 8th graders and presence of a retailer within a mile from school for 11th graders were associated with cannabis use and perceived harm. Additional policy efforts may further reduce youth exposure to cannabis.

Differentiating Diabetic Ketoacidosis and Hyperglycemic Ketosis Due to Cannabis Hyperemesis Syndrome in Adults With Type 1 Diabetes

OBJECTIVE

To differentiate diabetic ketoacidosis (DKA) from hyperglycemic ketosis due to cannabis hyperemesis syndrome (HK-CHS) in adults with type 1 diabetes.

RESEARCH DESIGN AND METHODS

Of 295 adults with type 1 diabetes who were seen with DKA-related ICD-10 codes, 68 patients with 172 DKA events meeting the inclusion criteria were analyzed. Cannabis use was defined as a positive urine test result for cannabis. Linear mixed models were used to define HK-CHS (pH ≥7.4 with bicarbonate ≥15 mmol/L [mEq/L]), and sensitivity and specificity were calculated using the receiver operating characteristic (ROC) curve.

RESULTS

Cannabis users had significantly higher pH (7.42 ± 0.01 vs. 7.09 ± 0.02) and bicarbonate (19.2 ± 0.61 vs. 9.1 ± 0.71 mmol/L) (P < 0.0001) compared with nonusers. The area under the ROC curve for a positive cannabis urine test result predicting HK-CHS was 0.9892.

CONCLUSIONS

In patients who present with DKA and higher pH, especially pH ≥7.4, cannabis use should be considered in the differential diagnosis.

Changes in California cannabis exposures following recreational legalization and the COVID-19 pandemic

INTRODUCTION

Since 2012, eighteen states and the District of Columbia have legalized recreational cannabis. Past research suggests this policy change is associated with increased cannabis exposures however this has not yet been studied in California, despite its status as the world's largest legal cannabis market.

METHODS

This observational, retrospective study analyzed trends in cannabis exposures reported to the California Poison Control System (CPCS) from 2010 to 2020. We assessed shifts in exposures before and after the legalization of recreational cannabis in November 2016, the establishment of recreational retail sales in January 2018, and the institution of a statewide shelter-in-place order due to the COVID-19 pandemic in March 2020 using interrupted time-series analysis and reviewed all records to identify specific products associated with exposures.

RESULTS

Between 2010 and 2020 edible exposures increased from near zero to 79% of exposures in 2020. Cannabis exposures significantly increased following recreational legalization in 2016 (by an estimated 2.07 exposures per month [CI: 0.60, 3.55]; p < 0.01) and initiation of retail sales in 2018 (0.85 [CI: 0.12, 1.58]; p < 0.05). There was no significant change in cannabis exposures following the first shelter-in-place order of the COVID-19 pandemic (1.59 [CI: -1.61, 3.68]; p = 0.43). Cannabis exposures for those thirteen and under increased significantly both after recreational legalization (1.04 [CI: 0.38, 1.70]) and after the opening of the retail sales market (0.73 [CI: 0.34, 1.12]), but not following the shelter-in-place order (1.59 [CI: -1.61, 3.68]), nor was there a significant change for those older than thirteen.

CONCLUSIONS

Our findings suggest that cannabis legalization is linked to increased exposures, particularly for products such as gummies and candy edibles among children under the age of thirteen. Clinicians should be aware of these risks and communicate them to patients, and policymakers should consider stronger regulations on packaging to reduce these exposures.Key pointsQuestion: How have cannabis exposures changed following legalization of recreational use, the opening of the recreational retail sales market, and the institution of shelter-in-place orders during the COVID-19 pandemic?Findings: In this retrospective review of 10,757 cases reported to the California Poison Control System (CPCS) between 2010 and 2020, exposures increased significantly after the legalization of recreational cannabis use and the opening of the recreational retail sales market, particularly among children, who primarily consumed candies and gummies.Meaning: Stronger regulation of cannabis edibles that mimic other products is warranted to decrease exposures among children.

Prevalence and Clinical Characteristics of Unintentional Ingestion of Marijuana in Children Younger Than 6 Years in States With and Without Legalized Marijuana Laws

OBJECTIVE

The aim of this study was to examine the relationship between state marijuana legalization and the rates of unintentional ingestions of marijuana in children younger than 6 years.

METHODS

This was a retrospective review of all marijuana ingestions in the National Poison Data System in children younger than 6 years between January 1, 2000, and July 31, 2017. Data analysis from NPDS included, age, sex, state and year of occurrence, clinical effects, therapies, health care facility utilization, and medical outcome. Population of children younger than 6 years was obtained from the US Census Bureau. Public records search provided state legal status of marijuana and year of state marijuana legalization.

RESULTS

From 2000 through 2008, there was no significant change in the annual number or rate of ingestions of marijuana in children younger than 6 years across the United States. Following 2009, there was mean annual increase of 27% per year, rising to 742 ingestions per year or 2.98 ingestions per 100,000 population, respectively, in 2017. More than 70% of all cases occurred in states with legalized marijuana. Of all pediatric patients, 54.6% received some form of hospital-based care, of which 7.5% required critical care. Pediatric patients experienced a wide range of symptoms from drowsiness and confusion, to seizures and coma. Medical treatments ranged from hydration therapy to sedation and intubation. Poison centers safely managed 23.4% of these pediatric cases by phone, without the need for hospital evaluation.

CONCLUSION

There was a strong association between the legalization of marijuana and ingestions of marijuana by children younger than 6 years.

Cannabinoid Use Among Liver Transplant Recipients

The effect of cannabinoids on liver transplant outcomes is an area of active research. We aimed to investigate marijuana (MJ) and cannabidiol (CBD) use among liver transplant recipients at the University of Colorado Hospital (UCH), specifically prevalence, habits, and predictors of use. Liver transplant recipients followed at UCH with valid email addresses were sent an informed consent postcard and survey invitation. This exploratory survey was conducted using REDCap. IBM SPSS Statistics software was used for statistical analysis. Of 1227 recipients who were sent surveys, 538 people responded. On average, respondents were 59 years old, with 63.7% male and 81.7% White. Hepatitis C virus (HCV; 30.4%) and alcohol use (17.7%) were the most common etiologies of liver disease. Among respondents, 23.8% reported current MJ use. Methods of use included smoking (72.4%), ingestion (55.3%), and vaporization (31.7%). Top reasons for MJ use were recreation (56.5%), anxiety (54.8%), and pain (53.2%). Among respondents, 21.0% currently used CBD, usually in the form of creams or lotions (58.9%) and to relieve pain (84.9%) and anxiety (31.1%). In multivariable analysis, age (odds ratio [OR], 0.941; 95% confidence interval [CI], 0.923-0.959; P < 0.001), diabetes mellitus (OR, 0.357; 95% CI, 0.171-0.746; P = 0.01), HCV cirrhosis (OR, 3.949; 95% CI, 2.281-6.835; P < 0.001), alcohol-related cirrhosis (OR, 2.101; 95% CI, 1.202-3.671; P = 0.01), and current tobacco use (OR, 2.918; 95% CI, 1.065-7.990; P = 0.04) were significant predictors of MJ use. Our study shows that cannabinoid use after liver transplant is common. MJ use is associated with decreasing age, alcohol-related and HCV cirrhosis, and tobacco use. Anxiety, pain, and recreation were top reasons for its use. Transplant teams should address reasons why their patients use MJ and CBD and develop programs to mitigate anxiety and pain after transplant. Further studies are needed to examine effects of cannabinoids on liver transplant outcomes.

QTc prolongation in cannabis hyperemesis syndrome patients exposed to antiemetics: A retrospective chart review

OBJECTIVE

To evaluate the risk of QT prolongation in patients treated for Cannabis Hyperemesis Syndrome (CHS) in the emergency department.

METHODS

This was a retrospective comprehensive chart review of patients in the University of Colorado Health Emergency Department. Charts were identified by ICD9/10 codes from January 1, 2012 to December 31, 2014 for cannabis use and data were manually abstracted. We performed chi-square and odds ratios, stratified by drug, to determine differences in medication induced QTc prolongation and performed logistic regression to predict prolongation greater than 500 ms. We captured adverse events from medications as a secondary outcome.

RESULTS

We found 282 cases of CHS during the study period. There were no significant differences between the median post-medication QTc value stratified by drug when all medications were analyzed simultaneously. A multiple logistic regression model showed that only a potassium below 3.0 mmol/L predicted QT prolongation greater than 500 msec.

CONCLUSION

Anti-emetics used to treat CHS did not result in significant QTC prolongation in this cohort.

Clearing the air: A study of cannabis-related presentations to urban Alberta emergency departments following legalization

OBJECTIVES

Non-medical cannabis recently became legal for adults in Canada. Legalization provides opportunity to investigate the public health effects of national cannabis legalization on presentations to emergency departments (EDs). Our study aimed to explore association between cannabis-related ED presentations, poison control and telemedicine calls, and cannabis legalization.

METHODS

Data were collected from the National Ambulatory Care Reporting System from October 1, 2013, to July 31, 2019, for 14 urban Alberta EDs, from Alberta poison control, and from HealthLink, a public telehealth service covering all of Alberta. Visitation data were obtained to compare pre- and post-legalization periods. An interrupted time-series analysis accounting for existing trends was completed, in addition to the incidence rate ratio (IRR) and relative risk calculation (to evaluate changes in co-diagnoses).

RESULTS

Although only 3 of every 1,000 ED visits within the time period were attributed to cannabis, the number of cannabis-related ED presentations increased post-legalization by 3.1 (range -11.5 to 12.6) visits per ED per month (IRR 1.45, 95% confidence interval [CI]; 1.39, 1.51; absolute level change: 43.5 visits per month, 95% CI; 26.5, 60.4). Cannabis-related calls to poison control also increased (IRR 1.87, 95% CI; 1.55, 2.37; absolute level change: 4.0 calls per month, 95% CI; 0.1, 7.9). Lastly, we observed increases in cannabis-related hyperemesis, unintentional ingestion, and individuals leaving the ED pre-treatment. We also observed a decrease in co-ingestant use.

CONCLUSION

Overall, Canadian cannabis legalization was associated with small increases in urban Alberta cannabis-related ED visits and calls to a poison control centre.

Pediatric cannabis intoxication trends in the pre and post-legalization era

INTRODUCTION

On April 13, 2017, a bill to legalize cannabis was introduced to the Canadian Parliament and presented to the public. On October 17, 2018, Canada legalized recreational cannabis use. We assessed intoxication severity, reflected by ICU admission rates, risk factors and other characteristics in children who presented to the emergency department (ED) with cannabis intoxication, before and after legalization.

METHODS

A retrospective cohort study of children 0-18 years who presented to a pediatric ED between January 1, 2008 and December 31, 2019 with cannabis intoxication. The pre-legalization period was defined from January 1, 2008 to April 12, 2017 and the peri-post legalization period from April 13, 2017 to December 31, 2019.

RESULTS

We identified 298 patients; 232 (77.8%) presented in the pre legalization period and 66 (22.1%) in the peri-post legalization period; median age: 15.9 years (range: 11 months-17.99 years). A higher proportion of children were admitted to the ICU in the peri-post legalization period (13.6% vs. 4.7%, respectively; p = .02). While the median monthly number of cannabis-related presentations did not differ between the time periods (2.1 [IQR:1.9-2.5] in the pre legalization period vs. 1.7 [IQR:1.0-3.0] in the peri-post legalization period; p = .69), the clinical severity did. The proportions of children with respiratory involvement (65.9% vs. 50.9%; p = .05) and altered mental status (28.8% vs. 14.2%; p < .01) were higher in the peri-post legalization period. The peri-post legalization period was characterized by more children younger than 12 years (12.1% vs. 3.0%; p = .04), unintentional exposures (14.4% vs, 2.8%; p = .002) and edibles ingestion (19.7% vs. 7.8%; p = .01). Edible ingestion was an independent predictor of ICU admission (adjusted OR: 4.1, 95%CI: 1.2-13.7, p = .02).

CONCLUSIONS

The recreational cannabis legalization in Canada is associated with increased rates of severe intoxications in children. Edible ingestion is a strong predictor of ICU admission in the pediatric population.

High-intensity cannabis use and hospitalization: a prospective cohort study of street-involved youth in Vancouver, Canada

BACKGROUND

There is concern that cannabis use negatively affects vulnerable groups such as youth; however, the relationship between cannabis use and health care utilization has not been well characterized in this population. We longitudinally evaluated the association between daily cannabis use and hospitalization among a prospective cohort of street-involved youth.

METHODS

Data were collected from the At-Risk Youth Study (ARYS) in Vancouver, Canada, from September 2005 to May 2015. Participants were interviewed semi-annually and multivariable generalized estimating equation (GEE) logistic regression was used to examine the relationship between daily cannabis use and hospitalization.

RESULTS

A total of 1216 participants (31.2% female) were included in this analysis, and 373 (30.7%) individuals reported hospitalization at some point during the study period. In a multivariable GEE analysis, daily cannabis use was not significantly associated with hospitalization (Adjusted Odds Ratio [AOR] = 1.17, 95% Confidence interval [CI] = 0.84, 1.65). We did observe a significant interaction between daily cannabis use and sex (AOR = 0.51, 95% CI = 0.34, 0.77), whereby cannabis use was associated with a decreased odds of hospitalization among males (AOR = 0.60, 95% CI = 0.47, 0.78), yet was not significantly associated with hospitalization among females (AOR = 1.19, 95% CI = 0.84, 1.67).

CONCLUSIONS

The finding that daily cannabis use was not associated with hospitalization among street-involved youth is encouraging given the high rates of cannabis use in this population and the expansion of cannabis legalization and regulation. Future studies, however, are warranted to monitor possible changes in the consequences of cannabis use as cannabis legalization and regulation increase internationally.

Down and High: Reflections Regarding Depression and Cannabis

In light of the recent changes in the legal status of cannabis in Canada, the understanding of the potential impact of the use of cannabis by individuals suffering from depression is increasingly considered as being important. It is fundamental that we look into the existing literature to examine the influence of cannabis on psychiatric conditions, including mood disorders. In this article, we will explore the relationship that exists between depression and cannabis. We will examine the impact of cannabis on the onset and course of depression, and its treatment. We have undertaken a wide-ranging review of the literature in order to address these questions. The evidence from longitudinal studies suggest that there is a bidirectional relationship between cannabis use and depression, such that cannabis use increases the risk for depression and vice-versa. This risk is possibly higher in heavy users having initiated their consumption in early adolescence. Clinical evidence also suggests that cannabis use is associated with a worse prognosis in individuals with major depressive disorder. The link with suicide remains controversial. Moreover, there is insufficient data to determine the impact of cannabis use on cognition in individuals with major depression disorder. Preliminary evidence suggesting that the endogenous cannabinoid system is involved in the pathophysiology of depression. This will need to be confirmed in future positron emission tomography studies. Randomized controlled trials are needed to investigate the potential efficacy of motivational interviewing and/or cognitive behavioral therapy for the treatment of cannabis use disorder in individuals with major depressive major disorder. Finally, although there is preclinical evidence suggesting that cannabidiol has antidepressant properties, randomized controlled trials will need to properly investigate this possibility in humans.

Acute cannabis intoxication in the emergency department: the effect of legalization

Background

On October 17, 2018, the Cannabis Act decriminalized the recreational use of cannabis in Canada. This study seeks to determine how legalization of cannabis has impacted emergency department (ED) visits for acute cannabis intoxication.

Methods

We conducted a retrospective chart review at an academic ED in Hamilton, Ontario. We assessed all visits with a cannabis-related ICD-10 discharge code 6 months before and after legalization (October 17, 2018) to determine cases of acute cannabis intoxication. The primary outcome was the rate of ED visits. Secondary outcomes included number of visits distributed by age, length of stay, co-ingestions, and clinical course in the emergency department (investigations and treatment).

Results

There was no difference in the overall rate of ED visits following legalization (2.44 vs. 2.94 visits/1000, p = 0.27). However, we noted a 56% increase in visits among adults aged 18–29 (p = 0.03). Following legalization, a larger portion of patients required observation without interventions (25% vs 48%, p < 0.05). Bloodwork and imaging studies decreased (53% vs. 12%, p < 0.05; 29% vs. 2%, p < 0.05); however, treatment with benzodiazepines increased (24% vs. 51%, p < 0.05).

Conclusions

Legalization was not associated with a change in the rate of cannabis-related ED visits in our study. More research is needed regarding changing methods of cannabis ingestion and trends among specific age groups.

When Cannabis Use Goes Wrong: Mental Health Side Effects of Cannabis Use That Present to Emergency Services

Cannabis use is a modifiable risk factor for the development and exacerbation of mental illness. The strongest evidence of risk is for the development of a psychotic disorder, associated with early and consistent use in youth and young adults. Cannabis-related mental health adverse events precipitating Emergency Department (ED) or Emergency Medical Services presentations can include anxiety, suicidal thoughts, psychotic or attenuated psychotic symptoms, and can account for 25-30% of cannabis-related ED visits. Up to 50% of patients with cannabis-related psychotic symptoms presenting to the ED requiring hospitalization will go on to develop schizophrenia. With the legalization of cannabis in various jurisdiction and the subsequent emerging focus of research in this area, our understanding of who (e.g., age groups and risk factors) are presenting with cannabis-related adverse mental health events in an emergency situation is starting to become clearer. However, for years we have heard in popular culture that cannabis use is less harmful or no more harmful than alcohol use; however, this does not appear to be the case for everyone. It is evident that these ED presentations should be considered another aspect of potentially harmful outcomes that need to be included in knowledge mobilization. In the absence of a clear understanding of the risk factors for mental health adverse events with cannabis use it can be instructive to examine what characteristics are seen with new presentations of mental illness both in emergency departments (ED) and early intervention services for mental illness. In this narrative review, we will discuss what is currently known about cannabis-related mental illness presentations to the ED, discussing risk variables and outcomes both prior to and after legalization, including our experiences following cannabis legalization in Canada. We will also discuss what is known about cannabis-related ED adverse events based on gender or biological sex. We also touch on the differences in magnitude between the impact of alcohol and cannabis on emergency mental health services to fairly present the differences in service demand with the understanding that these two recreational substances may impact different populations of individuals at risk for adverse events.

Topical Capsaicin for Treating Cannabinoid Hyperemesis Syndrome

Introduction

Cannabinoid hyperemesis syndrome (CHS), associated with chronic cannabis use, presents with cyclic abdominal pain, nausea, and vomiting. With increasing use of marijuana, the incidence of CHS is expected to increase. Most patients with CHS make frequent visits to the emergency room and are usually refractory to conventional treatment. We, therefore, present a case of CHS successfully treated with topical capsaicin application. Case Presentation. A 41-year-old female with a recent excess use of cannabis presented to the emergency department for evaluation of recurrent excruciating epigastric pain accompanied by severe nausea and vomiting. She had similar, milder symptoms a year ago and underwent endoscopic evaluation which was negative except for mild reflux esophagitis for which she was started on a proton pump inhibitor. On this presentation, basic laboratory workup, EKG, and CT scan of abdomen and pelvis were unremarkable. A detailed abdominal exam was only positive for mild epigastric tenderness. She was instructed to continue pantoprazole and pain medication and outpatient repeat esophagogastroduodenoscopy. The patient returned the next day with extreme retching, nausea, and vomiting and was admitted for further evaluation. Intravenous fluids, antiemetics, and morphine were started for pain control with no symptomatic improvement. A diagnosis of cannabis hyperemesis syndrome was made based on history of chronic marijuana use and otherwise negative workup. A trial of topical capsaicin, over the epigastric region, was tried that provided dramatic relief within 24 hours. Repeat endoscopic evaluation had no evidence of ulcers, celiac disease, or esophagitis. She was discharged on topical capsaicin and counselled on marijuana abstinence, with no return of symptoms.

Conclusion

Based on the dramatic resolution of symptoms with topical capsaicin, our case supports this promising intervention and provides an alternate approach to antiemetics and narcotics routinely used in patients with cannabis hyperemesis syndrome.

Trends in Web Searches About the Causes and Treatments of Autism Over the Past 15 Years: Exploratory Infodemiology Study

BACKGROUND

Ninety percent of adults in the United States use the internet, and the majority of internet users report looking on the web for health information using search engines. The rising prevalence of autism spectrum disorder (ASD), uncertainty surrounding its etiology, and variety of intervention approaches contribute to questions about its causes and treatments. It is not known which terms people search most frequently about ASD and whether web search queries have changed over time. Infodemiology is an area of health informatics research using big data analytics to understand web search behavior.

OBJECTIVE

The objectives were to (1) use infodemiological data to analyze trends in web-based searches about the causes and treatments of ASD over time and (2) inform clinicians and ASD organizations about web queries regarding ASD.

METHODS

Google Trends was used to analyze web searches about the causes and treatments of ASD in the United States from 2004 to 2019. The search terms analyzed for queries about causes of ASD included vaccines, genetics, environmental factors, and microbiome and those for therapies included applied behavior analysis (ABA), gluten-free diet, chelation therapy, marijuana, probiotics, and stem cell therapy.

RESULTS

Google Trends results are normalized on a scale ranging from 0 to 100 to represent the frequency and relative interest of search topics. For searches about ASD causes, vaccines had the greatest frequency compared to other terms, with an initial search peak observed in 2008 (scaled score of 81), reaching the highest frequency in 2015 (scaled score of 100), and a current upward trend. In comparison, searches about genetics, environmental factors, and microbiome occurred less frequently. For web searches about ASD therapies, ABA consistently had a high frequency of search interest since 2004, reaching a maximum scaled score of 100 in 2019. The analyses of chelation therapy and gluten-free diet showed trending interest in 2005 (scaled score of 68) and 2007 (scaled score of 100), respectively, followed by a steady decline since (scaled scores of only 10 and 16, respectively, in 2019). Searches related to ASD and marijuana showed a rise in 2009 (scaled score of 35), and they continue to trend upward. Searches about probiotics and stem cell therapy have been relatively low (scaled scores of 22 and 18, respectively), but are gradually gaining interest. Web search volumes for stem cell therapy in 2019 surpassed both gluten-free diet and chelation therapy as web-searched interventions for ASD.

CONCLUSIONS

Google Trends is an effective infodemiology tool to analyze large-scale web search trends about ASD. The results showed informative variation in search trends over 15 years. These data are useful to inform clinicians and organizations about web queries on topics related to ASD, identify knowledge gaps, and target web-based education and knowledge translation strategies.

Risk Management in First Aid for Acute Drug Intoxication

Drug abuse (cannabis, cocaine, opiates, and synthetic drugs) is an increasing phenomenon, especially in the younger population, thus leading to more cases of intoxication requiring evaluation in the emergency department and subsequent hospitalization. In 2017, 34.2% of students reported having used an illegal psychoactive substance in their lifetime, while 26% reported having done so over the past year. We made a review about the effectiveness of the role of the temporary observation unit in the emergency department to improve management of acute drugs intoxication. We checked medical literature from the last 10 years (2009-2019). The following electronic databases were systematically searched: MEDLINE-PubMed, Web of Science, Scopus, and the Cochrane Central Register of Controlled Trials. Then, a systematic review was carried out according to the Preferred Reporting Items for Systematic Review standards. Intoxicated patients usually display a favorable medical course, few diagnostic and therapeutic interventions, a short stay in the hospital, and, when hospitalization is needed, semi-intensive therapy is a feasible solution; therefore, intoxicated patients are ideal candidates for a temporary observation unit. The emergency department is very important to manage intoxicated patients; however, the hospitalization of these patients is often not necessary.

Management of Cannabinoid Hyperemesis Syndrome: Focus on Capsaicin

Cannabinoid hyperemesis syndrome is a condition characterized by cyclic severe nausea, vomiting, and abdominal pain associated with frequent, long-term marijuana use. The condition resolves with cessation of cannabis but may be temporarily relieved by bathing in hot water. Topical capsaicin cream may also alleviate symptoms, perhaps through antiemetic effects produced by activation of TRPV1 receptors, similar to that of hot water bathing. This review summarizes the epidemiology, clinical presentation, diagnosis, pathophysiology, and management of cannabinoid hyperemesis syndrome, focusing on treatment with topical capsaicin.

Role of Cannabis and Its Derivatives in Gastrointestinal and Hepatic Disease

Medical and recreational cannabis use has increased dramatically over the last decade, resulting from mainstream cultural acceptance and legalization in several countries worldwide. Cannabis and its derivatives affect many gastrointestinal processes via the endocannabinoid system (ECS). The ECS influences gastrointestinal homeostasis through anti-inflammatory, anti-nociceptive, and anti-secretory effects. Some gastrointestinal disorders might therefore be treated with cannabinoids. Despite numerous studies in cell lines and animals, few human studies have evaluated the therapeutic effects of cannabinoids. Cannabis' schedule 1 drug status has limited its availability in research; cannabis has been legalized only recently, in some states, for medicinal and/or recreational use. Cannabinoids can alleviate chemotherapy-induced nausea and emesis and chronic pain. Studies have demonstrated the important roles of the ECS in metabolism, obesity, and nonalcoholic fatty liver disease and the anti-inflammatory effects of cannabis have been investigated in patients with inflammatory bowel diseases. Despite its potential benefits, undesired or even detrimental effects of cannabis can limit its use. Side effects such as cannabinoid hyperemesis syndrome affect some users. We review the ECS and the effects of cannabis and its derivatives on gastrointestinal and hepatic function in health and disease.

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

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.

Assessing the public health impact of cannabis legalization in Canada: core outcome indicators towards an 'index' for monitoring and evaluation

The legalization of non-medical cannabis use and supply is impending in Canada. This constitutes a major policy change with the declared objective of improving public health outcomes, which requires rigorous monitoring and evaluation. While numerous different aspects associated with legalization will be examined, a focused perspective is required for effective policy evaluation purposes. To these ends, we have identified a set of 10 core indicators associated with cannabis-related risk/harm outcomes-based on current best evidence-that are expected to measure the primary impacts of legalization on public health outcomes. We briefly review these indicators, and their respective data availability in Canada. As ideally an integrated outcome assessment of cannabis legalization's impact on public health will be available, we further propose options to merge the individual indicators into an integrated, weighted 'index', considering their expected relative impact for public health. One possible approach to undertake this is 'multi-criteria decision analysis' as a method to weight the relative indicator impact on public health; alternative approaches are proposed. The integrated 'public health index' for cannabis legalization will allow for scientifically comprehensive, while focused, monitoring and evaluation of the effects of legalization in Canada for the benefits of science and evidence-based policy alike.

Personality Traits and Psychotic Proneness Among Chronic Synthetic Cannabinoid Users

OBJECTIVE

Chronic use of synthetic cannabinoids (SCs) has been associated with a wide range of negative consequences for health including psychotic and affective disturbances. Accumulating evidence indicates that cannabinoids use may be a risk factor for schizophrenia, and chronic natural cannabis users score higher than non-users on measures of schizotypal personality traits. However, little is known regarding the personality characteristics of SC users, especially in comparison with recreational cannabis users and healthy individuals. This study aimed to examine the differences in personality characteristics and schizotypy between SC users, regular cannabis users, and non-users and to compare these measures between groups.

METHODS

Forty-two chronic SC users, 39 natural cannabis users, and 47 non-using control participants, without history of mental disorder, or current substance use diagnosis (mean age 26± 4.47 years; 23 females, 105 males), completed the Big-Five Factor Inventory (BFI), the Schizotypal Personality Questionnaire-Brief (SPQ-B), substance use history, rating scales of depression and anxiety, and a demographic questionnaire.

RESULTS

On the BFI, SC users scored higher than natural cannabis users and non-users on neuroticism, but lower on agreeableness and extraversion, and endorsed greater schizotypal symptoms on the SPQ-B. In addition, SC users had lower scores on conscientiousness than non-users, and natural cannabis users were more extroverted than non-users. Higher openness and lower conscientiousness predicted schizotypy for both SC and natural cannabis users. Finally, greater neuroticism predicted schizotypy for natural cannabis users, and introversion predicted schizotypy for non-users.

CONCLUSIONS

These results show that chronic SC users differ from natural cannabis users and non-users on dimensions of specific personality traits and schizotypy that may indicate psychotic proneness.

Subjective effects of combustible, vaporized, and edible cannabis: Results from a survey of adolescent cannabis users

BACKGROUND

Data from controlled laboratory experiments in adults indicate that the subjective effects of cannabis vary by administration method (e.g., combustible, vaporized). Whether the subjective effects of cannabis experienced in the natural ecology and among adolescents differ by cannabis administration method is unknown. In this observational study, adolescents' retrospective reports of subjective effects after combustible, edible, and vaporized cannabis use were examined.

METHODS

Students from ten public schools in Los Angeles, CA, USA (M[SD] age = 16.1 [.43] years) who reported past 6-month use of combustible, edible, or vaporized cannabis (N = 584) were surveyed on subjective effects experienced after use (yes/no). They were provided with a 12 item self-report checklist of six positive (e.g., relaxed, energetic) and six negative (e.g., drowsy, lazy) subjective effects. For each method of administration, affirmative responses were summed in positive (range: 0-6) and negative (range: 0-6) effect composite scores.

RESULTS

Generalized estimating equations adjusted for demographics and recent cannabis use revealed a graded pattern of differences in positive subjective effects across products, with highest scores for combustible (M[SD] = 3.98[1.76]), followed by edible (M[SD] = 3.58 [2.04]) and vaporized (M[SD] = 3.11 [2.21]) cannabis (all pairwise cross-product contrasts p < .01). Mean negative effect score was highest for edible (M[SD] = 2.27 [1.95]), followed by combustible (M[SD] = 1.94 [1.66]), and vaporized (M[SD] = 1.34 [1.73]) cannabis, respectively (all pairwise contrasts p < .02).

CONCLUSION

Adolescents' reports of subjective effects varied across cannabis administration methods. Combustible cannabis' more desirable subjective effects profile might be indicative of higher abuse liability.

Cannabinoid1 (CB-1) receptor antagonists: a molecular approach to treating acute cannabinoid overdose

The legalization of cannabis for both recreational and medical use in the USA has resulted in a dramatic increase in the number of emergency department visits and hospital admissions for acute cannabinoid overdose (also referred to as cannabis intoxication and cannabis poisoning). Both “edibles” (often sold as brownies, cookies, and candies) containing large amounts of Δ⁹-tetrahydrocannabinol and synthetic cannabinoids (many possessing higher potencies and efficacies than Δ⁹-tetrahydrocannabinol) are responsible for a disproportionate number of emergency department visits relative to smoked cannabis. Symptoms of acute cannabinoid overdose range from extreme lethargy, ataxia, and generalized psychomotor impairment to feelings of panic and anxiety, agitation, hallucinations, and psychosis. Treatment of acute cannabinoid overdose is currently supportive and symptom driven. Converging lines of evidence indicating many of the symptoms which can precipitate an emergency department visit are mediated through activation of cannabinoid₁ receptors. Here, we review the evidence that cannabinoid₁ receptor antagonists, originally developed for indications ranging from obesity to smoking cessation and schizophrenia, provide a molecular approach to treating acute cannabinoid overdose.

Emergency department visits during the 4/20 cannabis celebration

BACKGROUND

Annual '4/20' cannabis festivals occur around the world on April 20 and often feature synchronised consumption of cannabis at 4:20 pm. The relationship between these events and demand for emergency medical services has not been systematically studied.

METHODS

We conducted a population-based retrospective cohort study in Vancouver, Canada, using 10 consecutive years of data (2009-2018) from six regional hospitals. The number of emergency department (ED) visits between 4:20 pm and 11:59 pm on April 20 were compared with the number of visits during identical time intervals on control days 1 week earlier and 1 week later (ie, April 13 and April 27) using negative binomial regression.

RESULTS

A total of 3468 ED visits occurred on April 20 and 6524 ED visits occurred on control days. A non-significant increase in all-cause ED visits was observed on April 20 (adjusted relative risk: 1.06; 95% CI 1.00 to 1.12). April 20 was associated with a significant increase in ED visits among prespecified subgroups including a 5-fold increase in visits for substance misuse and a 10-fold increase in visits for intoxication. The hospital closest to the festival site experienced a clinically and statistically significant 17% (95% CI 5.1% to 29.6%) relative increase in ED visits on April 20 compared with control days.

INTERPRETATION

Substance use at annual '4/20' festivals may be associated with an increase in ED visits among key subgroups and at nearby hospitals. These findings may inform harm reduction initiatives and festival medical care service planning.

Cohort study of medical cannabis authorisation and healthcare utilisation in 2014-2017 in Ontario, Canada

BACKGROUND

The impact of medical cannabis on healthcare utilisation between 2014 and 2017 in Ontario, Canada. With cannabis legalisation in Canada and some states in the USA, high-quality longitudinal cohort research studies are of urgent need to assess the impact of cannabis use on healthcare utilisation.

METHODS

A matched cohort study of 9925 medical cannabis authorised adult patients (inhaled (smoked or vaporised) or orally consumed (oils)) at specialised cannabis clinics, and inclusion of 17 732 controls (not authorised) between 24 April 2014 and 31 March 2017 from Ontario, Canada. Interrupted time series and multivariate Poisson regression analyses were conducted. Medical cannabis impact on healthcare utilisation was measured over 6 months: all-cause physician visits, all-cause hospitalisation, ambulatory care sensitive conditions (ACSC)-related hospitalisations, all-cause emergency department (ED) visits and ACSC-related ED visits.

RESULTS

For medical cannabis patients compared with controls, there was an initial (within the first month) increase in physician visits (additional 4330 visits per 10 000 patients). However, a numerical reduction was noted over the 6-month follow-up, and no statistical difference was observed (p=0.126). Likewise, in hospitalisations and ACSC ED visits, there was an initial increase (44 per 10 000 people, p<0.05) but no statistical difference after follow-up (p=0.34). Conversely, no initial increase in all-cause ED visits was observed with a slight decrease (19 visits per 10 000 patients, p=0.014) in follow-up.

CONCLUSIONS

An initial increase (within first month) in healthcare utilisation may be expected among medical cannabis users that appears to wane over time. Proactive follow-up of patients using medical cannabis is warranted to minimise initial risks to patients and actively assess potential benefits/harms of ongoing use.

Fatal crashes in the 5 years after recreational marijuana legalization in Colorado and Washington

Colorado and Washington legalized recreational marijuana in 2012, but the effects of legalization on motor vehicle crashes remains unknown. Using Fatality Analysis Reporting System data, we performed difference-in-differences (DD) analyses comparing changes in fatal crash rates in Washington, Colorado and nine control states with stable anti-marijuana laws or medical marijuana laws over the five years before and after recreational marijuana legalization. In separate analyses, we evaluated fatal crash rates before and after commercial marijuana dispensaries began operating in 2014. In the five years after legalization, fatal crash rates increased more in Colorado and Washington than would be expected had they continued to parallel crash rates in the control states (+1.2 crashes/billion vehicle miles traveled, CI: -0.6 to 2.1, p = 0.087), but not significantly so. The effect was more pronounced and statistically significant after the opening of commercial dispensaries (+1.8 crashes/billion vehicle miles traveled, CI: +0.4 to +3.7, p = 0.020). These data provide evidence of the need for policy strategies to mitigate increasing crash risks as more states legalize recreational marijuana.

Why do patients come to the emergency department after using cannabis?

Background: Cannabis (MJ) policy liberalization in a majority of US states has impacted emergency department (ED) visits. It is important to understand why people come to the ED after using MJ because the drug is now available to experienced and naïve people across the country. The objectives of this study were to (1) improve upon administrative dataset methodology by performing additional chart review to describe ED visits related to cannabis, (2) understand why patients come to the ED after using cannabis, and (3) begin to inform our understanding of cannabis-attributable ED visits to start to educate patients and providers about cannabis' safety.Methods: We performed a retrospective chart review of ED visits identified by cannabis ICD-9 and 10-CM codes between 2012 and 2016. Visits were reviewed and determined if the visit was partially attributable to cannabis based upon a pre-specified definition, then categorized into clinical complaint categories. Descriptive statistics, Chi-Square, and T-tests were used to elucidate the data.Results: About one-fourth (25.74%) of visits with cannabis ICD-CM codes were found to be at least partially attributable to cannabis. These patients are more often young, Caucasian males when compared to the overall ED population (p < .0001). Patients with a cannabis-attributable visit were more often admitted to the hospital (p < .0001). The most common complaints in cannabis-attributable visits were gastrointestinal and psychiatric complaints, as well as intoxication. The number of cannabis-attributable visits rose with time (p=.012).Conclusions: Based on a pre-specified definition, with good inter-rater reliability, we found that 25% of visits with a cannabis ICD-CM code were partially attributable to cannabis. These findings represent areas to target in cannabis user education as public perceptions change across time.