Cannabis

Changes in Cannabis Use Patterns in Psychiatric Populations Pre- and Post- Legalization of Recreational Cannabis Use in Canada: A Repeated Cross-Sectional Survey

Maryam Sorkhou — 2024-12-16

Objective: Since the federal Canadian government legalized cannabis in 2018, cannabis use in the general population has slightly increased. However, little is known about the impact of cannabis legalization on pattens of cannabis use in psychiatric populations. Method: We studied changes in daily/almost daily and average 30-day cannabis use amongst individuals currently using cannabis who reported past 12-month experiences of specific mental health disorders and among those without past 12-month experiences of any mental health disorder before and after Canadian legalization of recreational cannabis use (N = 13,527). Data came from Canadian respondents in Wave 1 (August–October 2018), Wave 2 (September–October 2019), and Wave 3 (September–November 2020) of the International Cannabis Policy Study (ICPS). Results: After adjustment for covariates, among individuals currently using cannabis, the odds of using cannabis daily/almost daily increased only in individuals with schizophrenia between Wave 1 and Waves 3 (a OR = 9.19, 95% CI: 2.46 – 34.37). Similarly, significant increases in average 30-day cannabis use between Wave 1 (M = 12.80, SE = 1.65) and Wave 3 (M = 18.07, SE = 1.03) were observed only among individuals with schizophrenia, F (1,2) = 4.58, p < .05. No significant changes in daily/almost daily or average past 30-day cannabis use were observed in those without mental health problems or those reporting anxiety, depression, PTSD, bipolar disorder, or substance use disorders. Conclusions: Since legalization, cannabis use has significantly increased only among people with schizophrenia, highlighting the need for targeted public health prevention programs.

Predictors of Change in Cannabis Use Status from Pre- to Post-Recreational Cannabis Legalization in Canada: Evidence from a Two-Wave Longitudinal National Survey

Daniel McGrath — 2024-12-16

Objective: In October 2018, the Government of Canada legalized cannabis for recreational use nationwide. The effects of legalization on cannabis use have been primarily assessed through cross-sectional surveys. Method: In the present study, a two-wave longitudinal design was used to explore potential demographic, substance use and behavioral addiction, and mental health predictors of change in cannabis use status following legalization. Canadian online panelists (18+) were initially surveyed about their gambling and substance use in 2018 (i.e., before cannabis legalization). From the original sample, 4,707 (46.2%) were retained in the follow-up survey one year later, post-cannabis legalization. These respondents were the focus of the present study. Results: When queried about how legalization would impact their use, 61.8% said, ‘I’ll never use it’, 21.1% stated ‘I’ll use it about the same as I do now’, 10.3% indicated ‘I may try it for the first time’, 5.0% answered ‘I’ll use it more’, and 1.9% responded that ‘I’ll use it less’. Consistent with these sentiments, within the retained sample there was a modest but significant increase in cannabis use from baseline (18.4%) to follow-up (26.1%). Regressions established that younger age, being male, substance use, tobacco or e-cigarette use, problematic gambling, and stated intention to use cannabis were predictors of later cannabis use. Conclusions: This national cohort design indicates that cannabis use appears to have increased in Canada following legalization. The present study makes a unique contribution by also identifying variables that statistically forecast movement toward and away from cannabis use.

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

Zina Zaslawski — 2024-12-16

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.

Mental Health and Dispositional Predictors of Simultaneous Versus Concurrent Cannabis and Alcohol Use in a Canadian Context

Jenna Vieira — 2024-12-16

Objective: Cannabis has become more available in Canada since its legalization in 2018. Many individuals who use cannabis also use alcohol (co-use), which can be used either at the same time such that their effects overlap (simultaneous use) or at different times (concurrent use). Though studies have identified predictors of co-use relative to single-substance use, less is known about the predictors of specific types of co-use. The present study examined the mental health and dispositional predictors of simultaneous relative to concurrent use of the two legal substances (cannabis and alcohol) among adults in Canada. Method: Canadian adults reporting past-year use of both cannabis and alcohol (N = 1,761) were recruited from Academic Prolific and six Canadian universities. Participants completed online self-report measures of demographic characteristics, cannabis and alcohol co-use, mental health symptoms, impulsivity, and personality traits. Results: Binary logistic regression analyses revealed that when independent variables were each examined individually, greater severity of depression, anxiety, PTSD, and ADHD symptoms; greater negative urgency and lack of premeditation; and greater impulsivity each predicted an increased likelihood of reporting past-year simultaneous use relative to concurrent use. When independent variables were grouped into three separate models (mental health, impulsivity, and personality variables), greater anxiety symptom severity, ADHD symptom severity, negative urgency, and sensation seeking were each uniquely associated with an increased likelihood of simultaneous relative to concurrent use. Conclusions:Individuals with elevated anxiety and ADHD symptoms, as well as negative urgency and sensation seeking, may be more inclined to engage in simultaneous use to self-medicate and achieve greater symptom reduction. Future studies may examine the directionality of these relations and motives (e.g., coping) that may differentiate simultaneous and concurrent use.

Expressive Writing About One's Trauma Increases Accessibility of Cannabis Information in Memory among Cannabis Users with Trauma Histories

Sarah DeGrace — 2024-12-16

Objective: Increasingly, cannabis is being prescribed/used to help manage posttraumatic stress symptoms (PTSS) or chronic pain, as cannabis has been argued to be beneficial for both types of symptoms. However, the evidence on efficacy is conflicting with evidence of risks mounting, leading some to caution against the use of cannabis for the management of PTSS and/or chronic pain. We examined the main and interactive effects of PTSS and chronic pain interference on adverse cannabis outcomes (a composite of cannabis uselevels and cannabis use disorder, CUD,symptoms). We hypothesized that chronic pain interference and PTSS would each significantly predict adverse cannabis outcomes, and that chronic pain interference effects on adverse cannabis outcomes would be strongest among those with greater PTSS. Method: Forty-seven current cannabis users with trauma histories and chronic pain (34% male; mean age=32.45 years) were assessed for current PTSS, daily chronic pain interference, past month cannabis use levels (grams), and CUD symptom count. Results: Moderator regression analyses demonstrated chronic pain interference significantly predicted the adverse cannabis outcomes composite, but only at high levels of PTSS. Conclusions: Cannabis users with trauma histories may be at greatest risk for heavier/more problematic cannabis use if they are experiencing both chronic pain interference and PTSS

Examining the Potential Impact of Recreational Cannabis Legalization on Individuals Receiving Treatment for Substance Use Disorder: An Interrupted Time Series Study in Guelph, Ontario, Canada

Emily M. Britton — 2024-12-16

Objective: The present research evaluated the impact of legalizing recreational cannabis among individuals with substance use disorders (SUD) who may already use cannabis at high rates. Methods: Using an interrupted time series study design, we evaluated the potential impact of legalization among individuals seeking treatment for SUD within a hospital-based treatment setting in Guelph, Ontario. We examined 2,925 individuals who entered the treatment program between April 2017 and December 2021. We performed segmented regression analyses using both the date of cannabis legalization and the date of edibles legalization as the interruption time point. We also performed stratified analyses to examine potential sex differences. Results: We found no significant changes in the prevalence of cannabis use or readiness to quit using cannabis following legalization with either of the interruption time points. However, there was evidence of increasing CUD severity post-edibles legalization. Stratified analyses also suggested possible sex differences in readiness to quit over time. Conclusions: Results point to some small but potentially important impacts of recreational cannabis legalization among individuals with SUD that may only continue with time. Nevertheless, there is a need to continue to monitor cannabis use trends to understand any potential lagged effects.

Examining the Relationship Between Cannabis Use and Mood, Anxiety, and Psychotic Symptoms in Psychiatric Patients with Severe Concurrent Mental Health and Substance Use Disorders Before and After Recreational Cannabis Legalization in Canada

Karina Thiessen — 2024-12-16

Objective: The relationship between cannabis use and mental health has garnered significant attention in recent decades. However, studies have largely been in general populations or in countries in which recreational cannabis use is illegal. Method: The current cross-sectional study examines the relationship between cannabis use, mood disorders, anxiety, and psychosis in an inpatient psychiatric population with severe concurrent mental health and substance use disorders, exploring the potential moderating effect of the legalization of recreational cannabis in Canada. Results: Cannabis use compared to non-use was associated with higher self-reported depression, anxiety, and psychotic symptoms but was not associated with diagnosis of a mood, anxiety, or psychotic disorder. Frequency of cannabis use was unrelated to mental health outcomes, but age of first use was negatively associated with self-reported psychoticism symptoms. There were some significant associations between recreational cannabis legalization and mental health, but legalization was largely unrelated to outcomes. There were also some significant differences by demographics. Conclusions: While findings are relatively consistent with prior literature, some significant associations differed, suggesting the importance of examining concurrent disorder patients as a unique population when examining relationships between cannabis use and mental health.

Legal Recreational Cannabis Sales and Opioid-Related Mortality in the 5 Years Following Cannabis Legalization in Canada: A Granger Causality Analysis

André J. McDonald — 2024-12-16

Objective: Little is known about the population-level impact of recreational cannabis legalization on trends in opioid-related mortality. Increased access to cannabis due to legalization has been hypothesized to reduce opioid-related deaths because of the potential opioid-sparing effects of cannabis. The objective of this study was to examine the relations between national retail sales of recreational (non-medical) cannabis and opioid overdose deaths in the 5 years following legalization in Canada. Method: Using time-series data, we applied Granger causality methods to evaluate the association between trends in legal recreational cannabis sales and opioid-related deaths over time. Both sales and opioid deaths grew over time, with the latter exhibiting significant increases following the onset of the COVID-19 pandemic. Results: We found no support for the hypothesis that increasing post-legalization sales Granger caused changes in opioid-related deaths in British Columbia, Ontario, or at the national level. Conclusions: These findings suggest that increases in legal recreational cannabis sales following legalization were not meaningfully associated with changes in opioid-related mortality. Further examination with longer follow-up periods will be needed as the legal cannabis market becomes more entrenched in Canada, but these findings converge with previous work suggesting legalization is not related to opioid overdose mortality and further undermine that hypothesized link as a basis for legalization in other jurisdictions.

Perceived Risk of Medical Cannabis and Prescribed Cannabinoids for Chronic Pain: A Cross-Sectional Study Among Quebec Clinicians

Gwenaelle De Clifford-Faugère — 2024-12-16

Objective: An increase in medical cannabis and prescribed cannabinoids use for chronic pain management has been observed in Canada in the past years. This study aimed to: 1) Describe clinicians’ perceived risk associated with the use of medical cannabis and prescribed cannabinoids for the management of chronic pain; and 2) Identify sociodemographic and professional factors associated with perceived risk of adverse effects. Method: A web-based cross-sectional study was conducted in Quebec, Canada in 2022. A convenience sample of 207 clinicians was recruited (physicians/pharmacists/nurse practitioners). They were asked to rate the risk of adverse effects associated with medical cannabis (e.g., smoke, or oil) and prescribed cannabinoids (e.g., nabilone) on a scale of 0 to 10 (0: no risk, 10: very high risk), respectively. Multiple linear regression was performed to identify factors associated with perceived risk. Results: Average perceived risk associated with medical cannabis and prescribed cannabinoids were 5.93 ± 2.08 (median:6/10) and 5.76 ± 1.81 (median:6/10). Factors associated with higher medical cannabis perceived risk were working in primary care (β = 1.38, p = .0034) or in another care setting (β = 1.21, p = .0368) as compared to a hospital setting. As for prescribed cannabinoids, being a pharmacist (β = 1.14, p = .0452), working in a primary care setting (β = 0.83, p = .0408) and reporting more continuing education about chronic pain (β = 0.02, p = .0416) were associated with higher perceived risk. No sex differences were found in terms of perceived risk. Conclusions: Considering the clinician’s experience provide insights on cannabis risk as these professionals are at the forefront of patient care when they encounter adverse effects.

Potential Risks from Cannabis-Infused Beverages: A Critical Review

Anna Marie Froude — 2024-12-16

Although Canada legalized cannabis beverages in 2019, most available research on acute cannabis intoxication derives from dried flower and edible products. The distinct bioavailability and pharmacokinetic properties of phytocannabinoids ingested from beverages, however, contribute to significantly different acute and long-term effects that need to be better understood to ensure consumer safety. Objective: This review investigates existing cannabis beverage literature, with a particular focus on acute intoxication effects. Method: PubMed, PsycINFO and Web of Science databases were systematically searched. A structured search generated 29 eligible studies, comprising studies of consumption patterns and beliefs, advertisements and marketing, acute effects in human models, and drink composition. Results: Human studies report aversive acute subjective and physiological effects induced by cannabis beverages in healthy, infrequent users. Beverages also showed inaccurate cannabinoid labeling, posing potential risks to consumers. This review highlights the paucity and inconsistency of available research, further exacerbated by the sheer diversity of formulations investigated, while beginning to address some questions surrounding the safety and risks associated with cannabis beverages. Conclusions: Given the extensive differences in effects across cannabis-infused beverages, and the growing ‘drinkables’ market, it is essential that more studies directly examine both acute and long-term impacts of cannabis beverage consumption.

Predictors of Response to Medical Cannabis for Chronic Pain: A Retrospective Review of Real-Time Observational Data

Aidan Giangregorio — 2024-12-16

Objective: People living with chronic pain increasingly use medical cannabis for symptom relief. We conducted a retrospective cohort study examining cannabis for chronic pain relief using anonymous archival data obtained from the medicinal cannabis tracking app, Strainprint®. Method: We acquired cannabis utilization data from 741 adults with chronic pain and used multilevel modeling to examine the association of age, sex, type of pain (muscle, joint or nerve pain), cannabis formulation (high CBD, balanced CBD:THC, or high THC), route of administration (inhaled or ingested), cannabis use before vs. during the COVID-19 pandemic, and duration of cannabis use, with pain relief. Results: Most patients were female (n = 464; 63%), with a mean age of 39 (SD = 11), and our cohort had completed a total of 83,622 tracked cannabis sessions through Strainprint. The majority of sessions reported use of inhaled cannabis products (78%), typically with high tetrahydrocannabinol (THC; 64%) versus high cannabidiol (CBD; 15%) or balanced THC:CBD (21%) products. The median change in pain scores across sessions was -3.0 points on a 10-point numeric rating scale (NRS; IQR -4.5 to -2.0). In our adjusted model, greater pain relief was associated with male vs. female sex (-0.69 points on a 10-point NRS; 95%CI -0.46 to -0.91). We found statistically significant, but trivial associations with joint pain (-0.05 points), balanced THC:CBD products in the long term (-0.003 points), and cannabis use during the pandemic (0.18 points). Conclusions: We found that people living with chronic pain report important pain relief when using cannabis for medical purposes, and that men may achieve greater pain relief than women.

Dried Cannabis Use, Tobacco Smoking, and COVID-19 Infection: Findings from a Longitudinal Observational Cohort Study

Nadia Milad — 2024-12-16

Objective: The potential impact of cigarette and cannabis smoking on COVID-19 infection outcomes is not well understood. We investigated the association between combustible tobacco use and dried cannabis use with COVID-19 infection in a longitudinal cohort of community adults. Method: The sample comprised 1,343 participants, originally enrolled in 2018, who reported their cigarette and cannabis use in 11 assessments over 44 months, until 2022. COVID-19 infection history were self-reported after the onset of the pandemic. Univariate and multivariate logistic regression analyses were performed. The potentially confounding factor of vaccination status was also considered by stratifying data by booster vaccination self-reporting. Results: Among 1,343 participants, 820 (61.1%) reported any COVID-19 infection. Dried cannabis use (46.3% of participants, n = 721) was associated with higher self-reporting of 2+ COVID-19 infections (13.3% vs. 7.3% in non-users, p = .0004), while tobacco use (18.5% of participants, n = 248) had no significant effect (13.3% vs. 10.0% in no use group, p = .116). When stratified into single or dual substance use groups, dried cannabis-only use was associated with increased reporting of 1 or 2+ COVID-19 infections compared to substance non-users, while tobacco-only use and dual use groups were not significantly different from non-users. To account for differences in vaccination rates between substance use groups, we found that, among individuals with a COVID-19 booster vaccine, dried cannabis use was still associated with increased reporting of 2+ COVID-19 infections (p = .008). Conclusions: Our study suggests that dried cannabis use is associated with a higher likelihood of reporting 2+ COVID-19 infections. Although the study was observational and relied on self-report infection status, our findings support the need for further investigation into the impact of cannabis use on COVID-19 infection, particularly studies employing controlled experimental designs.