Work-related and non-work-related mild traumatic brain injury: Associations with mental health and substance use challenges in a Canadian population-level survey.

BACKGROUND: Mild traumatic brain injury (mTBI) can profoundly impact overall health, employment, and family life. Incidence of mTBI in the workplace represents an important subgroup with poorer outcomes. Mental health (MH) and substance use (SU) challenges are a primary correlate of TBI, but are rarely assessed among individuals with a work-related (wr)-mTBI, particularly at a population-level. OBJECTIVE: This study aimed to assess the association between lifetime wr-mTBI and non-wr-mTBI and the experience of MH and SU challenges. METHODS: The 2019 Centre for Addiction and Mental Health (CAMH) Monitor is a cross-sectional telephone survey of adults aged≥18 years in Ontario, Canada, employing a stratified (six regions) two-stage (telephone number, respondent) list-assisted random digit dialing probability selection procedure (N = 1792). Adjusting for sociodemographic variables, binary logistic regression was conducted to assess the association between lifetime wr-mTBI and non-wr-mTBI (relative to no TBI) and four outcomes: hazardous use of alcohol and of cannabis, psychological distress, and fair/poor mental health. RESULTS: Adjusting for sociodemographic variables, non-wr-mTBI demonstrated increased odds of hazardous alcohol (AOR = 2.12, 95% CI = 1.41, 3.19) and cannabis use (AOR = 1.61, 95% CI = 1.05, 2.45), psychological distress (AOR = 1.68, 95% CI = 1.14, 2.49), and fair/poor mental health (AOR = 1.70, 95% CI = 1.11, 2.59). Lifetime wr-mTBI demonstrated increased odds of reporting psychological distress (AOR = 3.40, 95% CI = 1.93, 5.97) and fair/poor mental health (AOR = 2.16, 95% CI = 1.12, 4.19) only. CONCLUSIONS: Non-wr-mTBI was associated with both MH and SU, whereas wr-mTBI was associated with MH only. MH outcomes were more strongly associated with wr-mTBI than non-wr-mTBI. Physicians, employers, and insurers need to consider the potential association between wr-mTBI and MH, and provide care accordingly.

Social determinants of health associated with psychological distress stratified by lifetime traumatic brain injury status and sex: Cross-sectional evidence from a population sample of adults in Ontario, Canada.

This study identified the social determinants of health (SDoH) associated with psychological distress in adults with and without a self-reported history of traumatic brain injury (TBI), stratified by sex. Data from the 2014-2017 cycles of the Centre for Addiction and Mental Health Monitor Survey, a representative survey of adults ≥18 years in Ontario, Canada, were analyzed (N = 7,214). The six-item version of the Kessler Psychological Distress Scale was used to determine moderate to severe psychological distress. Self-reported lifetime TBI was defined as a head injury resulting in a loss of consciousness for ≥5 minutes or at least one-night stay in the hospital (16.4%). Among individuals reporting a history of TBI, 30.2% of males and 40.1% of females reported psychological distress (p = 0.0109). Among individuals who did not report a history of TBI, 17.9% of males and 23.5% of females reported psychological distress (p<0.0001). Multivariable logistic regression analyses showed that the SDoH significantly associated with elevated psychological distress were similar between individuals with and without a history of TBI. This included unemployment, student, or 'other' employment status among both males and females; income below the provincial median and age 65+ among males; and rural residence among females. This study highlighted opportunities for targeted population-level interventions, namely accessible and affordable mental health supports for individuals with lower income. Notably, this study presented evidence suggesting adaptations to existing services to accommodate challenges associated with TBI should be explored, given the finite and competing demands for mental health care and resources.

Separate and combined effects of alcohol and cannabis on mood, subjective experience, cognition and psychomotor performance: A randomized trial.

Co-use of alcohol and cannabis is associated with increased frequency and intensity of use and related problems. This study examined acute effects of alcohol and cannabis on mood, subjective experience, cognition, and psychomotor performance. Twenty-eight healthy cannabis users aged 19-29 years with recent history of binge drinking completed this within-subjects, double-blind, double-dummy, placebo-controlled, randomized clinical trial. Participants received: placebo alcohol and placebo cannabis (<0.1% THC); alcohol (target breath alcohol content [BrAC] 80 mg/dL) and placebo cannabis; placebo alcohol and active cannabis (12.5% THC); and active alcohol and cannabis over four sessions. Profile of Mood States (POMS), Addiction Research Centre Inventory (ARCI), verbal free recall (VFR), Digit Symbol Substitution Test (DSST), Continuous Performance Test (CPT), and grooved pegboard (GPB) task were administered before and approximately 75 min after drinking alcohol (1 h after smoking cannabis ad libitum). Significant effects of condition were found for the POMS (Tension-Anxiety, Confusion) and ARCI (MBG, LSD, PCAG, Euphoria, Sedation), predominantly with greater increases emerging after cannabis or alcohol-cannabis combined relative to placebo. Significant effects were found for VFR (immediate total and delayed recall, percent retained), DSST (trials attempted, trials correct, reaction time), and GPB (non-dominant hand) predominantly with greater declines in performance after alcohol and alcohol-cannabis combined relative to placebo and/or cannabis. Cannabis appeared to affect mood and subjective experience, with minimal impact on cognitive performance. Alcohol appeared to impair cognitive and psychomotor performance, with minimal impact on mood and subjective experience. Acute effects of alcohol and cannabis combined were additive at most.

Mu opioid receptor gene variant modulates subjective response to smoked cannabis.

The mu-opioid receptor (MOR) mediates the rewarding properties of many psychoactive drugs and is an important target in the treatment of addictions. Functional interactions between the opioid and endocannabinoid systems are established and have been hypothesized to contribute to the effects of cannabis. We investigated associations between three single nucleotide polymorphisms in the MOR gene OPRM1 (rs1799971, rs2281617, and rs510769) and subjective responses to smoked cannabis. Fifty-two regular cannabis users (1-4 days/week) were given a cannabis cigarette (12.5% THC) and rated their subjective responses on visual analog scales at baseline and at multiple time points after smoking. Blood samples were collected for THC quantification. There was a significant impact of the intronic variant rs510769 on subjective cannabis effects and THC blood levels. The influence of this gene variant may thus be mediated by pharmacodynamics and/or pharmacokinetic factors. We provide novel evidence that variability in OPRM1 contributes to individual responses to cannabis and may affect risk of cannabis use disorder. Our findings add to the growing body of literature on the genetic basis of individual responses to cannabis and may have implications for targeting the endogenous opioid system in the treatment of cannabis use disorder.

Effects of combining alcohol and cannabis on driving, breath alcohol level, blood THC, cognition, and subjective effects: A narrative review.

Alcohol and cannabis are the two most commonly found intoxicating substances in fatally injured drivers. Epidemiological studies have demonstrated that the use of alcohol or cannabis can lead to an increase in the risk of a motor vehicle collision. Reducing the risks associated with driving under the influence of alcohol or cannabis is achieved partly through roadside detection of breath alcohol concentrations (BrAC) or blood delta-9-tetrahydrocannabinol (THC) levels. The purpose of the present review is to compile the laboratory studies on the combined effects of alcohol and cannabis on simulated driving as well as those evaluating combinations of these drugs on BrAC or blood THC. Given that driving can be affected by a number of cognitive processes, the literature on the cognitive effects of combinations of alcohol and cannabis is also reviewed, along with a discussion of a potential additive effect on the subjective qualities of these drugs. In sum, it is concluded that alcohol and cannabis have additive effects on driving skills, cognition and subjective effects. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Cannabis Legalization and Detection of Tetrahydrocannabinol in Injured Drivers.

BACKGROUND: The effect of cannabis legalization in Canada (in October 2018) on the prevalence of injured drivers testing positive for tetrahydrocannabinol (THC) is unclear. METHODS: We studied drivers treated after a motor vehicle collision in four British Columbia trauma centers, with data from January 2013 through March 2020. We included moderately injured drivers (those whose condition warranted blood tests as part of clinical assessment) for whom excess blood remained after clinical testing was complete. Blood was analyzed at the provincial toxicology center. The primary outcomes were a THC level greater than 0, a THC level of at least 2 ng per milliliter (Canadian legal limit), and a THC level of at least 5 ng per milliliter. The secondary outcomes were a THC level of at least 2.5 ng per milliliter plus a blood alcohol level of at least 0.05%; a blood alcohol level greater than 0; and a blood alcohol level of at least 0.08%. We calculated the prevalence of all outcomes before and after legalization. We obtained adjusted prevalence ratios using log-binomial regression to model the association between substance prevalence and legalization after adjustment for relevant covariates. RESULTS: During the study period, 4339 drivers (3550 before legalization and 789 after legalization) met the inclusion criteria. Before legalization, a THC level greater than 0 was detected in 9.2% of drivers, a THC level of at least 2 ng per milliliter in 3.8%, and a THC level of at least 5 ng per milliliter in 1.1%. After legalization, the values were 17.9%, 8.6%, and 3.5%, respectively. After legalization, there was an increased prevalence of drivers with a THC level greater than 0 (adjusted prevalence ratio, 1.33; 95% confidence interval [CI], 1.05 to 1.68), a THC level of at least 2 ng per milliliter (adjusted prevalence ratio, 2.29; 95% CI, 1.52 to 3.45), and a THC level of at least 5 ng per milliliter (adjusted prevalence ratio, 2.05; 95% CI, 1.00 to 4.18). The largest increases in a THC level of at least 2 ng per milliliter were among drivers 50 years of age or older (adjusted prevalence ratio, 5.18; 95% CI, 2.49 to 10.78) and among male drivers (adjusted prevalence ratio, 2.44; 95% CI, 1.60 to 3.74). There were no significant changes in the prevalence of drivers testing positive for alcohol. CONCLUSIONS: After cannabis legalization, the prevalence of moderately injured drivers with a THC level of at least 2 ng per milliliter in participating British Columbia trauma centers more than doubled. The increase was largest among older drivers and male drivers. (Funded by the Canadian Institutes of Health Research.).

Influence of personality on acute smoked cannabis effects on simulated driving.

A recent study of the impact of smoked cannabis on simulated driver behavior demonstrated a reduction in mean speed after smoked cannabis. Previous research identified an association between personality and individual differences and acute drug effects. The present study examined the impact of personality on the reduction in mean speed after smoking cannabis under single- and dual-task driving conditions originally reported by Brands et al. (2019). Sixty-one participants randomly assigned to the active drug condition completed a battery of self-report questionnaires measuring various personality constructs and subsequently operated a driving simulator before and 30 min after smoking a 12.5% Δ9-tetrahydrocannabinol (THC) cigarette. Linear regression modeling tested the influence of self-reported driving errors, lapses, and violations, driver vengeance, psychological distress, impulsivity, and sensation seeking on the reduction in speed after smoking cannabis. After adjusting for the influence of sex, blood THC concentration, and predrug mean speed, impulsivity was a significant predictor of change in speed under both single- (ß = -.45, t = -3.94, p < .001) and dual- (ß = -.35, t = -2.74, p = .008) task driving conditions after cannabis. Higher trait impulsivity was significantly associated with greater reductions in driving speed after cannabis use, which may reflect greater sensitivity to drug effects and a stronger compensatory response. Further multidisciplinary study, including neurochemical, genetic, and psychological components, would be beneficial in helping to better understand how impulsivity and other personality or individual differences may impact the effects of cannabis on driver behavior and performance. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Associations of cannabis use, opioid use, and their combination with serious psychological distress among Ontario adults.

Considering the widespread use of cannabis and opioids, examining the use of cannabis, opioids and their combination with serious psychological distress (SPD) is important. A total of N = 12,358 adults participating in the Monitor surveillance study between 2014 and 2019 were included. Cannabis and opioid use reflected any use of the substances in the past 12 months. SPD was defined as having a score of 13 or more on the Kessler-6 questionnaire, a 6-item scale that includes feeling nervous, hopeless, restless or fidgety, sad or depressed. Odds ratios (ORs) were estimated from logistic regression models accounting for complex survey design and sociodemographic factors. Overall, 12.8% of the sample reported cannabis use only, 18% reported opioid use only, and 4.9% reported both cannabis and opioid use. Use of both cannabis and opioids was significantly associated with SPD in both women (OR = 4.24; 95% CI, 2.34 to 7.69), and in men (OR = 2.99; 95% CI, 1.56 to 5.73) compared to use of neither. The joint association of cannabis and opioids with SPD was additive. Addressing those who use both cannabis and opioids may help reduce the burden of SPD among adults in Ontario.

Combined effect of alcohol and cannabis on simulated driving.

RATIONALE: With alcohol and cannabis remaining the most commonly detected drugs in seriously and fatally injured drivers, there is a need to understand their combined effects on driving. OBJECTIVES: The present study examined the effects of combinations of smoked cannabis (12.5% THC) and alcohol (target BrAC 0.08%) on simulated driving performance, subjective drug effects, cardiovascular measures, and self-reported perception of driving ability. METHODS: In this within-subjects, double-blind, double-dummy, placebo-controlled, randomized clinical trial, cannabis users (1-7 days/week) aged 19-29 years attended four drug administration sessions in which simulated driving, subjective effects, cardiovascular measures, and whole blood THC and metabolite concentrations were assessed following placebo alcohol and placebo cannabis (<0.1% THC), alcohol and placebo cannabis, placebo alcohol and active cannabis, and alcohol and active cannabis. RESULTS: Standard deviation of lateral position in the combined condition was significantly different from the placebo condition (p < 0.001). Standard deviation of lateral position was also significantly different from alcohol and cannabis alone conditions in the single task overall drive (p = 0.029 and p = 0.032, respectively), from the alcohol alone condition in the dual task overall drive (p = 0.022) and the cannabis alone condition in the dual task straightaway drive (p = 0.002). Compared to the placebo condition, the combined and alcohol conditions significantly increased reaction time. Subjective effects in the combined condition were significantly greater than with either of the drugs alone at some time points, particularly later in the session. A driving ability questionnaire showed that participants seemed unaware of their level of impairment. CONCLUSION: Combinations of alcohol and cannabis increased weaving and reaction time, and tended to produce greater subjective effects compared to placebo and the single drug conditions suggesting a potential additive effect. The fact that participants were unaware of this increased effect has important implications for driving safety.

Cannabis, Impaired Driving, and Road Safety: An Overview of Key Questions and Issues.

The road safety impact of cannabis has been a topic of much discussion and debate over the years. These discussions have been revitalized in recent years by initiatives in several jurisdictions to legalize non-medical cannabis. Canada became the second country to legalize non-medical cannabis use in October, 2018, preceded by Uruguay in December 2013. Road safety concerns were key issues in the Canadian government's deliberations on the issue. In this paper, we identify several key questions related to the impact of cannabis on road safety, and provide a consideration of the relevant literature on these questions. These questions cover several perspectives. From an epidemiological perspective, perhaps the central question is whether cannabis use contributes to the chances of being involved in a collision. The answer to this question has evolved in recent years as the ability to conduct the relevant studies has evolved. A related question is the extent to which cannabis plays an important role in road safety, and recent research has made progress in estimating the collisions, injuries, and deaths that may be attributed to cannabis use. Several questions relate to the behavioral and pharmacological effects of cannabis. One central question is whether cannabis affects driving skills in ways that can increase the chances of being involved in a collision. Another important question is whether the effects of the drug on the driving behavior of medical users is similar to, or different from, the effects on non-medical users and whether there are sex differences in the pharmacological and behavioral effects of cannabis. Other important questions are the impact of tolerance to the effects of cannabis on road safety as well as different routes of administration (e.g., edibles, vaped). It remains unclear if there is a dose-response relationship of cannabis to changes in driving. These and other key questions and issues are identified and discussed in this paper.

Driving under the influence of cannabis risk perceptions and behaviour: A population-based study in Ontario, Canada.

Driving under the influence of cannabis (DUIC) is detrimental to road safety. Risk perception is a strong determinant of DUIC behaviour, yet little is known about the factors influencing DUIC risk perception in the general population. The objective of this study was to identify factors associated with risk perceptions of motor vehicle collision and legal consequences due to DUIC and examine whether these perceptions were associated with DUIC behaviour. Data were derived from the 2017 CAMH Monitor, a cross-sectional telephone survey of adults aged 18+ years in Ontario, Canada (n = 1813). Multivariable logistic regression analyses were performed. Approximately 90% of adults overall agreed that DUIC increases motor vehicle collision risk compared to 55% of those reporting past-year DUIC. Being male, less educated, and using cannabis at least monthly were associated with disagreeing that DUIC increases motor vehicle collision risk. Being male, young, and using cannabis at least monthly were associated with agreeing that DUIC is safer than driving under the influence of alcohol (DUIA). Being male and using cannabis less than monthly were associated with agreeing that the chances of getting caught for DUIC are higher than DUIA. Safety but not legal risk perceptions were associated with DUIC behaviour among cannabis-using drivers. Cannabis legalization provides a timely opportunity for DUIC prevention strategies. This study suggests that policymakers should target male cannabis users and highlight the safety risks of DUIC. Further research is needed to assess the effectiveness of prevention measures and the impact of cannabis legalization on DUIC perceptions and behaviour.

Preliminary Eye-Tracking Data as a Nonintrusive Marker for Blood Δ-9-Tetrahydrocannabinol Concentration and Drugged Driving.

Background: Cannabis is one of the drugs most often found in drivers involved in serious motor vehicle collisions. Validity and reliability of roadside cannabis detection strategies are questioned. This pilot study aimed to investigate the relationship between eye characteristics and cannabis effects in simulated driving to inform potential development of an alternative detection strategy. Materials and Methods: Multimodal data, including blood samples, eye-tracking recordings, and driving performance data, were acquired from 10 participants during a prolonged single-session driving simulator experiment. The study session included a baseline driving trial before cannabis exposure and seven trials at various times over ∼5 h after exposure. The multidimensional eye-tracking recording from each driving trial for each participant was segmented into nonoverlapping epochs (time windows); 34 features were extracted from each epoch. Blood Δ-9-tetrahydrocannabinol (THC) concentration, standard deviation of lateral position (SDLP), and mean vehicle speed were target variables. The cross-correlation between the temporal profile of each eye-tracking feature and target variable was assessed and a nonlinear regression analysis evaluated temporal trend of features following cannabis exposure. Results: Mean pupil diameter (r=0.81-0.86) and gaze pitch angle standard deviation (r=0.79-0.87) were significantly correlated with blood THC concentration (p<0.01) for all epoch lengths. For driving performance variables, saccade-related features were among those showing the most significant correlation (r=0.61-0.83, p<0.05). Epoch length significantly affected correlations between eye-tracking features and speed (p<0.05), but not SDLP or blood THC concentration (p>0.1). Temporal trend analysis of eye-tracking features after cannabis also showed a significant increasing trend (p<0.01) in saccade-related features, including velocity, scanpath, and duration, as the influence of cannabis decreased by time. A decreasing trend was observed for fixation percentage and mean pupil diameter. Due to the lack of placebo control in this study, these results are considered preliminary. Conclusion: Specific eye characteristics could potentially be used as nonintrusive markers of THC presence and driving-related effects of cannabis. clinicaltrials.gov (NCT03813602).

Influence of Cannabinoid Receptor 1 Genetic Variants on the Subjective Effects of Smoked Cannabis.

As many jurisdictions consider relaxing cannabis legislation and usage is increasing in North America and other parts of the world, there is a need to explore the possible genetic differences underlying the subjective effects of cannabis. This pilot study investigated specific genetic variations within the cannabinoid receptor 1 (CNR1) gene for association with the subjective effects of smoked cannabis. Data were obtained from a double-blinded, placebo-controlled clinical trial studying the impact of cannabis intoxication on driving performance. Participants randomized to the active cannabis group who consented to secondary genetic analysis (n = 52) were genotyped at the CNR1 rs1049353 and rs2023239 polymorphic areas. Maximum value and area under the curve (AUC) analyses were performed on subjective measures data. Analysis of subjective effects by genotype uncovered a global trend towards greater subjective effects for rs1049353 T-allele- and rs2023239 C-allele-carrying subjects. However, significant differences attributed to allelic identity were only documented for a subset of subjective effects. Our findings suggest that rs1049353 and rs2023239 minor allele carriers experience augmented subjective effects during acute cannabis intoxication.

Sex differences in the acute pharmacological and subjective effects of smoked cannabis combined with alcohol in young adults.

Objective: The prevalence of co-use of alcohol and cannabis is increasing, particularly among young adults. Sex differences in the effects of alcohol alone and cannabis alone have been observed in animals and humans. However, sex differences in the acute pharmacological effects of cannabis combined with alcohol have not yet been studied. In young adults, aged 19-29 years, we aimed to examine sex differences following an intoxicating dose of alcohol (target 0.08% breath alcohol content) combined with a moderate dose of cannabis (12.5% Δ9-tetrahydrocannabinol; THC) using an ad libitum smoking procedure. Method: Using a within-subjects design, 28 regular cannabis users (16 males; 12 females) received in random order: (a) placebo alcohol and placebo cannabis, (b) active alcohol and placebo cannabis, (c) placebo alcohol and active cannabis, and (d) active alcohol and active cannabis. Blood samples for THC were collected and measures of vital signs, subjective drug effects, and cognition were collected. Results: In the alcohol-cannabis combined condition, females smoked significantly less of the cannabis cigarette compared to males (p < .001), although both sexes smoked similar amounts in the other conditions. There was minimal evidence that females and males differed in THC blood concentrations, vitals, subjective effects, or cognitive measures. Conclusions: In the alcohol-cannabis combined condition, females experienced the same acute pharmacological and subjective effects of alcohol and cannabis as males, after smoking less cannabis, which has potential implications for informing education and policy. Further research is warranted on sex differences in cannabis pharmacology, as well as the combined effects of alcohol and cannabis. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Adult attention-deficit hyperactivity disorder symptoms and psychological distress, hazardous drinking, and problem gambling: A population-based study.

Recognition of ADHD in the adult population is relatively recent. Epidemiological research examining the mental health impact of ADHD in adulthood is thus limited. The objective of this study was to examine whether adult ADHD symptoms are associated with psychological distress, hazardous drinking, and problem gambling, after controlling for traumatic brain injury and sociodemographic characteristics. We analyzed data from a population-based survey administered in 2015 and 2016 to adults aged 18 years and over in Ontario, Canada (N = 3,817). Logistic regression was used to construct unadjusted and multivariable models for each of the three focal relationships. In the unadjusted models, ADHD symptoms were significantly related to psychological distress (OR = 9.3; 95% CI:6.1, 14.0) and hazardous drinking (OR = 2.1; 95% CI: 1.3, 3.4), but not to problem gambling (OR = 1.5; 0.5, 4.3). After adjustment, ADHD symptoms were significantly related to psychological distress (OR = 7.1; 95% CI: 4.6, 11.1), but not hazardous drinking (OR = 1.4; 95% CI: 0.8, 2.5) or problem gambling (OR = 0.6; 95% CI: 0.2, 2.5). This study further highlights the importance of clinicians assessing for concomitant ADHD and psychological distress in adults.

Ethnicity, Immigration Status, And Driving Under The Influence Of Alcohol.

BACKGROUND: Understanding risk factors for driving under the influence of alcohol (DUIA) informs development of effective interventions. This study examined the association between ethnicity, immigration status, and DUIA, exploring psychological distress and hazardous drinking as additional contributors. METHOD: Data were derived from the 2003-2011 cycles of the Centre for Addiction and Mental Health (CAMH) Monitor of 16,101 adults from Ontario, Canada. Hierarchical binary logistic regression analysis assessed self-identified ethnicity and immigration status as predictors of DUIA, adjusting for sociodemographics and driving exposure (Model 1), psychological distress (Model 2), and hazardous drinking (Model 3). RESULTS: In Model 1, respondents born outside of Canada had reduced odds of engaging in DUIA compared to those born in Canada (AOR = 0.72, 95%CI = 0.56 - 0.92). Relative to those identifying as Canadian, the odds of DUIA were significantly reduced for those identifying as East Asian (AOR = 0.28, 95%CI = 0.13 - 0.61) and South Asian (AOR = 0.52, 95%CI = 0.27 - 0.98). In Model 3, individuals who reported psychological distress (AOR = 1.69, 95%CI = 1.33 - 2.16) and those who reported hazardous drinking (AOR = 6.28, 95%CI= 5.13 - 7.69) were more likely to DUIA. Those identifying as East Asian continued to have reduced odds of DUIA compared to those identifying as Canadian (AOR = 0.38, 95%CI = 0.17 - 0.85). CONCLUSION: Individuals born outside of Canada were less likely to engage in DUIA than individuals born in Canada. Drivers who self-identified as East Asian were less likely to DUIA than those who self-identified as Canadian. Understanding ethnic differences underlying divergent risks for DUIA will improve prevention initiatives and remedial measures programming.

Increases in Serious Psychological Distress among Ontario Students between 2013 and 2017: Assessing the Impact of Time Spent on Social Media.

OBJECTIVE: The objective of the current research was to examine the association between time spent on social media and serious psychological distress between 2013 and 2017, a period when the rates of both were trending upward. METHODS: The current study analyzed population-based data from 3 waves of the Ontario Student Drug Use and Health Survey (N = 15,398). Multivariate logistic regression models were used to examine the association between time spent on social media and serious psychological distress controlling for theoretically relevant covariates. Interactions were tested to assess whether the association changed over time. RESULTS: The prevalence of serious psychological distress increased from 10.9% in 2013 to 16.8% in 2017 concomitantly with substantial increases in social media usage, especially at the highest levels. In the multivariate context, we found a significant interaction between social media use and the survey year which indicates that the association between time spent on social media and psychological distress has decreased from 2013 to 2017. CONCLUSION: Although both social media use and psychological distress increased between 2013 and 2017, the interaction between these variables indicates that the strength of this association has decreased over time. This finding suggests that the higher rate of heavy social media use in 2017 compared to 2013 is not actually associated with the higher rate of serious psychological distress during the same time period. From a diffusion of innovation perspective, it is possible that more recent adopters of social media may be less prone to psychological distress. More research is needed to understand the complex and evolving association between social media use and psychological distress. Researchers attempting to isolate the factors associated with the recent increases in psychological distress could benefit from broadening their investigation to factors beyond time spent on social media.

Prevalence and Correlates of Medicinal Cannabis Use Among Adolescents.

PURPOSE: Prior studies of medicinal cannabis use (MCU) have focused primarily on adults. This study examined the prevalence and correlates of self-reported MCU among adolescents. METHODS: Secondary school students (grades 9-12; N = 3,221) completed a cross-sectional survey in classrooms across Ontario, Canada, in 2016-2017. Participants reported on cannabis use behavior, cannabis dependence, other drugs use, and general health and sleep. Participants reporting cannabis use in the past year were grouped based on whether they reported MCU or not (i.e., recreational cannabis use only [RCU-only]). RESULTS: An estimated 6.89% (95% confidence interval 5.48%-8.63%) of students reported MCU, representing one quarter of the students reporting current cannabis use. Relative to the RCU-only group, the MCU group reported using cannabis more frequently, were more likely to report vaping and eating cannabis, had greater risk for cannabis dependence, perceived cannabis as less harmful, were more likely to report tobacco use, recreational use of other drugs, and medicinal use of sedatives or tranquilizers, and were less likely to report good health and sleeping for seven or more hours per night. Frequency of cannabis use accounted for differences between MCU and RCU-only groups in cannabis dependence risk, recreational use of other drugs, and perceiving cannabis as harmful, but it did not account for the other differences. CONCLUSIONS: A sizable portion of secondary school students report MCU, which appears to be associated with more frequent cannabis use and certain substance use and health-related correlates. Research is needed to further characterize motives for self-reported MCU among adolescents.

Alcohol retail privatisation in Canadian provinces between 2012 and 2017. Is decision making oriented to harm reduction?

INTRODUCTION: Policy changes may contribute to increased alcohol-related risks to populations. These include privatisation of alcohol retailing, which influences density of alcohol outlets, location of outlets, hours of sale and prevention of alcohol sales to minors or intoxicated customers. Meta-analyses, reviews and original research indicate enhanced access to alcohol is associated with elevated risk of and actual harm. We assess the 10 Canadian provinces on two alcohol policy domains-type of alcohol control system and physical availability of alcohol-in order to track changes over time, and document shifting changes in alcohol policy. METHODS: Our information was based on government documents and websites, archival statistics and key informant interviews. Policy domains were selected and weighted for their degree of effectiveness and population reach based on systematic reviews and epidemiological evidence. Government representatives were asked to validate all the information for their jurisdiction. RESULTS: The province-specific reports based on the 2012 results showed that 9 of 10 provinces had mixed retail systems-a combination of government-run and privately owned alcohol outlets. Recommendations in each provincial report were to not increase privatisation. However, by 2017 the percentage of off-premise private outlets had increased in four of these nine provinces, with new private outlet systems introduced in several. DISCUSSION AND CONCLUSIONS: Decision-making protocols are oriented to commercial interests and perceived consumer convenience. If public health and safety considerations are not meaningfully included in decision-making protocols on alcohol policy, then it will be challenging to curtail or reduce harms.