Physician Follow-Up of Pediatric and Young Adult Emergency Department Visits for Substance Use in Ontario, Canada.

PURPOSE: To study the proportion and predictors of outpatient physician follow-up within 60 days of substance-related emergency department (ED) visits for Ontario youth. METHODS: We examined administrative data on substance-related ED visits before and during the COVID-19 pandemic among youths aged 10-24 years in Ontario, Canada. Substance-related visits were identified using International Classification of Diseases-10-CA codes. We described demographic characteristics, receipt of mental health services in the year before the ED visit, disposition from the ED, and follow-up services within 60 days of the ED visit. RESULTS: Between April 1, 2017, and May 31, 2021, 64,236 youth had at least one ED visit for substance use. Visits for alcohol were the most common (49%), followed by cannabis (32.3%). ED visits for all substances were more prevalent during the pandemic than prepandemic, except visits for alcohol. The receipt of follow-up physician care for substance use was low (33.2% prepandemic) but increased during the pandemic (41.7%; adjusted odds ratio 1.34, 95% CI 1.28, 1.39) and varied between substances. Mental health service history in the year before the substance-related ED visit had the strongest association with receipt of follow-up physician care within 60 days (adjusted odds ratio 6.86, 95% CI 6.57, 7.17). DISCUSSION: Youth frequently do not receive physician follow-ups within two months of the substance-related ED visit, although higher follow-up proportions were seen during the pandemic after the implementation of virtual care. Further research is required to understand why follow-up is low and to examine interventions that can increase connection to care.

Mental health service use among mothers and other birthing parents during the COVID-19 pandemic in Ontario, Canada.

BACKGROUND: Parents have reported increased symptoms of depression and anxiety during the COVID-19 pandemic. This study evaluated changes in mental health and addiction (MHA)-related health service use among mothers and other birthing parents during the COVID-19 pandemic. METHODS: We conducted a repeated cross-sectional study using health administrative data in Ontario, Canada. The population included all mothers and birthing parents (≥1 child aged 1-18, no children <1 to exclude postpartum parents) between January 2016 and December 2021. We compared rates of MHA-related outpatient physician visits, hospitalizations, and emergency department (ED) visits during COVID-19 (March 2020-December 2021) to pre-COVID-19 (pre-March 2020). RESULTS: MHA-related outpatient visit rates increased by 17 % (rate ratio (RR) 1.17, 95 % CI 1.16-1.18) during COVID-19. Monthly utilization rates remained higher than expected across the COVID-19 period. MHA-related ED visit rates remained lower than expected during COVID-19, while MHA-related hospitalization rates returned to expected levels by August 2020. The largest relative increases in MHA-related outpatient visits during COVID-19 were in mothers and other birthing parents living in higher income (RR 1.20, 95 % CI 1.19-1.22) or urban areas (RR 1.20, 95 % CI 1.18-1.21), with children aged 1-3 years (RR 1.23, 95 % CI 1.20-1.25) and with no history of MHA-related health service use (RR 1.20, 95 % CI 1.19-1.21). LIMITATIONS: This study only captured physician-delivered MHA-related health service use. CONCLUSIONS: The COVID-19 pandemic was associated with an increase in MHA-related outpatient visits among mothers and other birthing parents. These findings point to the need for improvements in mental health service access.

Correction to "Changes in cannabis involvement in emergency department visits for anxiety disorders after cannabis legalization: a repeated cross-sectional study" - The Lancet Regional Health - Americas 2024; 36: 100815.

[This corrects the article DOI: 10.1016/j.lana.2024.100815.].

Physician Posttraumatic Stress Disorder During COVID-19: A Systematic Review and Meta-Analysis.

Importance: The COVID-19 pandemic placed many physicians in situations of increased stress and challenging resource allocation decisions. Insight into the prevalence of posttraumatic stress disorder in physicians and its risk factors during the COVID-19 pandemic will guide interventions to prevent its development. Objective: To determine the prevalence of posttraumatic stress disorder (PTSD) among physicians during the COVID-19 pandemic and examine variations based on factors, such as sex, age, medical specialty, and career stage. Data Sources: A Preferred Reporting Items for Systematic Reviews and Meta-analyses-compliant systematic review was conducted, searching MEDLINE, Embase, and PsychInfo, from December 2019 to November 2022. Search terms included MeSH (medical subject heading) terms and keywords associated with physicians as the population and PTSD. Study Selection: Peer-reviewed published studies reporting on PTSD as a probable diagnosis via validated questionnaires or clinician diagnosis were included. The studies were reviewed by 6 reviewers. Data Extraction and Synthesis: A random-effects meta-analysis was used to pool estimates of PTSD prevalence and calculate odds ratios (ORs) for relevant physician characteristics. Main Outcomes and Measures: The primary outcome of interest was the prevalence of PTSD in physicians, identified by standardized questionnaires. Results: Fifty-seven studies with a total of 28 965 participants and 25 countries were included (of those that reported sex: 5917 of 11 239 [52.6%] were male and 5322 of 11 239 [47.4%] were female; of those that reported career stage: 4148 of 11 186 [37.1%] were medical trainees and 7038 of 11 186 [62.9%] were attending physicians). The estimated pooled prevalence of PTSD was 18.3% (95% CI, 15.2%-22.8%; I2 = 97%). Fourteen studies (22.8%) reported sex, and it was found that female physicians were more likely to develop PTSD (OR, 1.93; 95% CI, 1.56-2.39). Of the 10 studies (17.5%) reporting age, younger physicians reported less PTSD. Among the 13 studies (22.8%) reporting specialty, PTSD was most common among emergency department doctors. Among the 16 studies (28.1%) reporting career stage, trainees were more prone to developing PTSD than attendings (OR, 1.33; 95% CI, 1.12-1.57). Conclusions and Relevance: In this meta-analysis examining PTSD during COVID-19, 18.3% of physicians reported symptoms consistent with PTSD, with a higher risk in female physicians, older physiciansy, and trainees, and with variation by specialty. Targeted interventions to support physician well-being during traumatic events like pandemics are required.

Changes in cannabis involvement in emergency department visits for anxiety disorders after cannabis legalization: a repeated cross-sectional study.

Background: An increasing number of countries have or are considering legalizing cannabis. One concern is that legalization of cannabis will result in increased cannabis use and in turn a higher prevalence of anxiety disorders. We examined changes in emergency department (ED) visits for anxiety disorders with cannabis involvement in Ontario, over a period that involved medical and non-medical cannabis legalization. Methods: This repeated cross-sectional population-based study identified all ED visits for anxiety disorders from residents of Ontario, Canada aged 10-105 between 2008 and 2022 (n = 15.7 million individuals). We used interrupted time series analyses to examine immediate and gradual changes in cannabis-involvement and alcohol-involvement (control condition) over four policy periods: medical cannabis legalization (January 2008-November 2015), expanded medical access (December 2015-September 2018), non-medical cannabis legalization with restrictions (October 2018-February 2020), and commercialization which overlapped with the COVID-19 pandemic (March 2020-December 2022). Poisson models were used to generate incidence rate ratios with 95% confidence intervals. Findings: Over the 14-year study, there were 438,700 individuals with one or more ED visits for anxiety disorders of which 3880 (0.89%) individuals had cannabis involvement and 6329 (1.45%) individuals had alcohol involvement. During the commercialization/COVID-19 period monthly rates of anxiety disorders with cannabis-involvement were 156% higher (0.11 vs 0.29 per 100,000 individuals) relative to the pre-legalization period, compared to a 27% increase for alcohol-involvement (0.27 vs 0.35 per 1100,000 individuals). Rates of anxiety ED visits with cannabis involvement per 100,000 individuals increased gradually over the study period with no immediate or gradual changes after expanded medical access, legalization with restrictions or commercialization/COVID-19. However, during the commercialization/COVID-19 period there were large declines in total anxiety disorder ED visits and anxiety disorder ED visits with alcohol-involvement. Consequently, during this period there was an immediate 31.4% relative increase in the proportion of anxiety visits with cannabis-involvement (incidence rate ratio [IRR], 1.31; 95% CI 1.05-1.65). Interpretation: We found large relative increases in anxiety disorder ED visits with cannabis involvement over a 14-year period involving medical and non-medical cannabis legalization. These findings may reflect increasing anxiety disorder problems from cannabis use, increasing self-medication of anxiety disorders with cannabis use, or both. The proportion of anxiety ED visits with cannabis involvement increased during the final period of the study but could have been the results of the market commercialization, COVID-19 or both and ongoing monitoring is indicated. Funding: Canadian Institutes of Health Research (grant #452360).

COVID-19 vaccine uptake among Ontario physicians: a descriptive population-based retrospective cohort study.

OBJECTIVES: To determine COVID-19 vaccine uptake among physicians in Ontario, Canada from 14 December 2020 to 13 February 2022. DESIGN: Population-based retrospective cohort study. SETTING: All registered physicians in Ontario, Canada using data from linked provincial administrative healthcare databases. PARTICIPANTS: 41 267 physicians (including postgraduate trainees) who were Ontario residents and registered with the College of Physicians and Surgeons of Ontario were included. Physicians who were out of province, had not accessed Ontario Health Insurance Plan-insured services for their own care for ≥5 years and those with missing identifiers were excluded. PRIMARY AND SECONDARY OUTCOME MEASURES: Primary outcomes were the proportions of physicians who were recorded to have received at least one, at least two and three doses of a Health Canada-approved COVID-19 vaccine by study end date. Secondary outcomes were how uptake varied by physician characteristics (including age, sex, specialty and residential location) and time elapsed between doses. RESULTS: Of 41 267 physicians, (56% male, mean age 47 years), 39 359 (95.4%) received at least one dose, 39 148 (94.9%) received at least two doses and 35 834 (86.8%) received three doses of a COVID-19 vaccine. Of those who received three doses, the proportions were 90.4% among those aged ≥60 years and 81.2-89.5% among other age groups; 88.7% among family physicians and 89% among specialists. 1908 physicians (4.6%) had no record of vaccination, and this included 3.4% of family physicians and 4.1% of specialists; however, 28% of this group had missing specialty information. CONCLUSIONS: In Ontario, within 14 months of COVID-19 vaccine availability, 86.8% of physicians had three doses of a COVID-19 vaccine, compared with 45.6% of the general population. Findings may signify physicians' confidence in the safety and effectiveness of COVID-19 vaccines.

The association between alcohol retail access and health care visits attributable to alcohol for individuals with and without a history of alcohol-related health-care use.

BACKGROUND AND AIMS: Alcohol retail access is associated with alcohol use and related harms. This study measured whether this association differs for people with and without heavy and disordered patterns of alcohol use. DESIGN: The study used a repeated cross-sectional analysis of health administrative databases. SETTING, PARTICIPANTS/CASES: All residents of Ontario, Canada aged 10-105 years with universal health coverage (n = 10 677 604 in 2013) were included in the analysis. MEASUREMENTS: Quarterly rates of emergency department (ED) and outpatient visits attributable to alcohol in 464 geographic regions between 2013 and 2019 were measured. Quarterly off-premises alcohol retail access scores were calculated (average drive to the closest seven stores) for each geographic region. Mixed-effect linear regression models adjusted for area-level socio-demographic covariates were used to examine associations between deciles of alcohol retail access and health-care visits attributable to alcohol. Stratified analyses were run for individuals with and without prior alcohol-attributable health-care use in the past 2 years. FINDINGS: We included 437 707 ED visits and 505 271 outpatient visits attributable to alcohol. After adjustment, rates of ED visits were 39% higher [rate ratio (RR) = 1.39, 95% confidence interval (CI) = 1.20-1.61] and rates of outpatient visits were 49% higher (RR = 1.49, 95% CI = 1.26-1.75) in the highest versus lowest decile of alcohol access. There was a positive association between alcohol access and outpatient visits attributable to alcohol for individuals without prior health-care attributable to alcohol (RR = 1.65, 95% CI = 1.39-1.95 for the highest to lowest decile of alcohol access) but not for individuals with prior health-care attributable to alcohol (RR = 1.08, 95% CI = 0.90-1.30). There was a positive association between alcohol access and ED visits attributable to alcohol for individuals with and without prior health-care for alcohol for ED visits. CONCLUSION: In Ontario, Canada, greater alcohol retail access appears to be associated with higher rates of emergency department (ED) and outpatient health-care visits attributable to alcohol. Individuals without prior health-care for alcohol may be more susceptible to greater alcohol retail access for outpatient but not ED visits attributable to alcohol.

Geographic clustering of cannabis stores in Canadian cities: A spatial analysis of the legal cannabis market 4 years post-legalisation.

INTRODUCTION: Following the legalisation of non-medical cannabis in 2018, the number of cannabis stores in Canada has rapidly expanded with limited regulation on their geographic placement. This study characterised the clustering of cannabis stores in Canadian cities and evaluated the association of clustering with provincial policy and sociodemographic variables. METHODS: Cross-sectional spatial analysis of cannabis store density in dissemination areas ('neighbourhoods', n = 39,226) in Canadian cities in September 2022. Cannabis store density was defined as the count of stores within 1000 m of a neighbourhood centre. Clusters of high-density cannabis retail were identified using Local Indicators of Spatial Autocorrelation. Associations between provincial policy (privatised vs. public market), sociodemographic variables and cannabis store density were evaluated using multivariable regression. RESULTS: Clusters of high-density cannabis retail were identified in 86% of Canadian cities, and neighbourhoods in clusters had a median of 5 stores within 1000 m. Toronto, Canada's most populous city, had the most extreme clustering where neighbourhoods in clusters had a median of 10 stores (and a maximum of 25 stores) within 1000 m. Neighbourhoods in private versus public retail markets had a significantly higher neighbourhood-level density of cannabis stores (adjusted rate ratio [aRR] 63.37, 95% confidence interval [CI] 25.66-156.33). Lower neighbourhood income quintile was also associated with a higher neighbourhood-level density of cannabis stores (Q5 vs. Q1, aRR 1.28, 95% CI 1.17-1.40). DISCUSSION AND CONCLUSIONS: Since cannabis was legalised, clusters of high-density cannabis retail have emerged in most Canadian cities and were more likely to form lower income neighbourhoods and in private retail markets.

The association between physical availability of cannabis retail outlets and frequent cannabis use and related health harms: a systematic review.

An increasing number of regions have or are considering legalising the sale of cannabis for adult use. Experience from tobacco and alcohol regulation has found that greater access to physical retail stores is positively associated with increased substance use and harm. Whether this association exists for cannabis is unclear. We completed a systematic review examining the association between cannabis retail store access and adverse health outcomes. We identified articles up until July 20, 2023 by searching four databases. We included studies examining the association between measures of cannabis store access and adverse outcomes: frequent or problematic cannabis use, healthcare encounters due to cannabis use (e.g., cannabis-induced psychosis), and healthcare encounters potentially related to cannabis (e.g., self-harm episodes). Results were compared by study design type, retail access measure, and by subgroups including: children, adolescents, young adults, adults, and pregnant individuals. This review was registered with PROSPERO (CRD42021281788). The search generated 5750 citations of which we included 32 studies containing 44 unique primary analyses (unique retail measure and outcome pairs). Studies come from 4 countries (United States, Canada, Netherlands and Uruguay). Among the included analyses, there were consistent positive associations between greater cannabis retail access and 1) increased healthcare service use or poison control calls directly due to cannabis (10/12 analyses; 83%) (2) increased cannabis use and cannabis-related hospitalization during pregnancy (4/4; 100%) and 3) frequent cannabis use in adults and young adults (7/11; 64%). There was no consistent positive association between greater cannabis retail and increased frequent cannabis use in adolescents (1/4; 25%), healthcare service use potentially related to cannabis (2/6; 33%) or increased adverse neonatal birth outcomes (2/7; 26.8%). There is a positive association between greater cannabis store access and increases in cannabis harm. In countries with legal cannabis, retail restrictions may reduce use and harm. Funding: Canadian Centre on Substance Use and Addiction (CCSA).

Development of an anxiety disorder following an emergency department visit due to cannabis use: a population-based cohort study.

Background: There is ongoing uncertainty about whether cannabis use increases the risk of developing an anxiety disorder. In this study we estimated the risk of having an incident healthcare visit for an anxiety disorder following an emergency department (ED) visit for cannabis use and explored factors associated with increased risk. Methods: We used health administrative data to perform a population-based cohort study of all individuals aged 10-105 years with no previous healthcare visits for anxiety disorders in Ontario, Canada, between January 2008 and March 2019. We compared the risk of having an incident healthcare visit for an anxiety disorder in the ED or hospital (primary analysis) or additionally in an outpatient setting (secondary analysis) for individuals with an incident ED visit for cannabis to members of the general population using cumulative incidence functions and cause-specific hazard models adjusted for relevant confounders. Findings: Our study included 12,099,144 individuals aged 10-105 without prior care for an anxiety disorder in the ED or hospital, of which 34,822 (0.29%) had an incident ED visit due to cannabis. Within 3-years of an incident ED visit due to cannabis, 12.3% (n = 4294) of individuals had an incident ED visit or hospitalization for an anxiety disorder-a 3.7-fold (adjusted Hazard Ratio [aHR] 3.69 95% CI 3.57-3.82) increased risk relative to the general population (1.2%). In secondary analysis, further excluding individuals with prior outpatient care for anxiety disorders, 23.6% of individuals with an ED visit due to cannabis had an incident outpatient visit, ED visit, or hospitalization for an anxiety disorder within 3-years compared to 5.6% of individuals in the general population (aHR 3.88 95% CI 3.77-2.99). The risk of having an incident healthcare visit for an anxiety disorder was higher in individuals with ED visits for cannabis use compared to the general population across all age and sex strata. However, younger males with ED visits for cannabis use (aHR 5.67 95% CI 5.19-6.21) had a greater risk relative to the general population than younger women with cannabis use (aHR 3.22 95% CI 2.95-3.52). Interpretation: ED visits for cannabis use were associated with an increased risk of having an incident healthcare visit for an anxiety disorder, particularly in young males. These findings have important clinical and policy implications given the increasing use of cannabis over time and trend towards legalization of cannabis. Funding: Canadian Institutes for Health Research.

Cannabis-involvement in emergency department visits for self-harm following medical and non-medical cannabis legalization.

AIMS: Cannabis use may increase the risk of self-harm, but whether legalization of cannabis is associated with changes in self-harm is unknown. We examined changes in cannabis-involvement in emergency department (ED) visits for self-harm after the liberalization of medical and legalization of non-medical cannabis in Canada. METHODS: This repeated cross-sectional study used health administrative data to identify all ED visits for self-harm in individuals aged ten and older between January 2010 and December 2021. We identified self-harm ED visits with a co-diagnosis of cannabis (main exposure) or alcohol (control condition) and examined changes in rates of visits over four distinct policy periods (pre-legalization, medical liberalization, non-medical legalization with restrictions, and non-medical commercialization/COVID-19) using Poisson models. RESULTS: The study included 158,912 individuals with one or more self-harm ED visits, of which 7810 (4.9 %) individuals had a co-diagnosis of cannabis use and 24,761 (15.6 %) had a co-diagnosis of alcohol use. Between 2010 and 2021, the annual rate of ED visits for self-harm injuries involving cannabis per 100,000 individuals increased by 90.1 % (3.6 in 2010 to 6.9 in 2021 per 100,000 individuals), while the annual rate of self-harm injuries involving alcohol decreased by 17.3 % (168.1 in 2010 to 153.1 in 2021 per 100,000 individuals). The entire increase in visits relative to pre-legalization occurred after medical liberalization (seasonally adjusted Risk Ratio [asRR] 1.71 95 % CI 1.09-1.15) with no further increases during the legalization with restrictions (asRR 1.77 95%CI 1.62-1.93) or commercialization/COVID-19 periods (asRR 1.63 95%CI 1.50-176). CONCLUSIONS: Cannabis-involvement in self-harm ED visits almost doubled over 12 years and may have accelerated after medical cannabis liberalization. While the results cannot determine whether cannabis is increasingly causing self-harm ED visits or whether cannabis is increasingly being used by individuals at high risk of self-harm, greater detection for cannabis use in this population and intervention may be indicated.

The effect of non-medical cannabis retailer proximity on use of mental health services for psychotic disorders in Ontario, Canada.

BACKGROUND: Cannabis is associated with the onset and persistence of psychotic disorders. Evidence suggests that accessibility of substances is associated with an increased risk of use-related harms. We sought to examine the effect of residing in proximity to non-medical cannabis retailers on the prevalence of health service use for psychosis. METHODS: We conducted a cross-sectional study using linked health administrative data, and used geospatial analyses to determine whether people in Ontario, Canada (aged 14-60 years) resided within walking (1.6 km) or driving (5.0 km) distance of non-medical cannabis retailers (open as of February-2020). We identified outpatient visits, emergency department (ED) visits, and hospitalizations for psychotic disorders between 01-April-2019 and 17-March-2020. We used zero-inflated Poisson regression models and gamma generalized linear models to estimate the association between cannabis retailer proximity and indicators of health service use. RESULTS: Non-medical cannabis retailers were differentially located in areas with high levels of marginalization and pre-existing health service use for psychosis. People residing within walking or driving distance of a cannabis retailer had a higher rate of psychosis-related outpatient visits, ED visits, and hospitalizations, compared to people living outside these areas. This effect was stronger among those with no prior service use for psychosis. CONCLUSIONS: Proximity to a non-medical cannabis retailer was associated with higher health service use for psychosis, even after adjustment for prior health service use. These findings suggest that opening of non-medical cannabis retailers could worsen the burden of psychosis on mental health services in areas with high-risk populations.

New perspectives on how to formulate alcohol drinking guidelines.

BACKGROUND: Low-Risk Alcohol Drinking Guidelines (LRDGs) aim to reduce the harms caused by alcohol. However, considerable discrepancies exist in the 'low-risk' thresholds employed by different countries. ARGUMENT/ANALYSIS: Drawing upon Canada's LRDGs update process, the current paper offers the following propositions for debate regarding the establishment of 'low-risk' thresholds in national guidelines: (1) as an indicator of health loss, years of life lost (YLL) has several advantages that could make it more suitable for setting guidelines than deaths, premature deaths or disability adjusted years of life (DALYs) lost. (2) Presenting age-specific guidelines may not be the most appropriate way of providing LRDGs. (3) Given past overemphasis on the so-called protective effects of alcohol on health, presenting cause-specific guidelines may not be appropriate compared with a 'whole health' effect derived from a weighted composite risk function comprising conditions that are causally related to alcohol consumption. (4) To help people reduce their alcohol use, presenting different risk zones associated with alcohol consumption instead of a single low risk threshold may be advantageous. CONCLUSIONS: National LRDGs should be based on years of life lost and should be neither age-specific nor cause-specific. We recommend using risk zones rather than a single drinking threshold to help people assess their own risk and encourage the adoption of behaviours with positive health impacts across the alcohol use spectrum.

Unintentional pediatric poisonings before and during the COVID-19 pandemic: A population-based study.

OBJECTIVES: The impact of coronavirus disease 2019 (COVID-19) on unintentional pediatric poisonings is unclear. We examined changes in emergency department (ED) visits and hospitalizations for poisonings before and during the COVID-19 pandemic. We compared changes in cannabis vs non-cannabis poisoning events given the recent legalization of cannabis in October 2018 and cannabis edibles in January 2020. STUDY DESIGN: Interrupted time-series (ITS) analyses of changes in population-level ED visits and hospitalizations for poisonings in children aged 0-9 years in Ontario, Canada (annual population of 1.4 million children), over two time periods: pre-pandemic (January 2010-March 2020) and pandemic (April 2020-December 2021). RESULTS: Overall, there were 28,292 ED visits and 2641 hospitalizations for unintentional poisonings. During the pandemic, poisonings per 100,000 person-years decreased by 14.6% for ED visits (40.15 pre- vs. 34.29 during) and increased by 35.9% for hospitalizations (3.48 pre- vs. 4.73 during). ED visits dropped immediately (Incidence Rate Ratio [IRR], 0.76; 95% CI, 0.70-0.82) at the onset of the pandemic, followed by a gradual return to baseline (quarterly change, IRR 1.04, 95%CI 1.03-1.06), while hospitalizations had an immediate increase (IRR 1.34; 95% CI, 1.08-1.66) and no gradual change. The only increase in poisonings was for cannabis which had a 10.7-fold for ED visits (0.45 to 4.83 per 100,000 person-years) and a 12.1-fold increase for hospitalizations (0.16 to 1.91 per 100,000 person-years). Excluding cannabis, there was no overall increase in poisoning hospitalizations. CONCLUSIONS: The COVID-19 pandemic was not associated with increases in any type of unintentional pediatric poisonings, with the exception of cannabis poisonings. Increased cannabis poisonings may be explained by the legalization of non-medical cannabis edibles in Canada in January 2020.

Impact of non-medical cannabis legalization with market restrictions on health service use and incident cases of psychotic disorder in Ontario, Canada.

BACKGROUND: Cannabis is a risk factor in the onset and persistence of psychotic disorders. There is concern that non-medical cannabis legalization in Canada may have population-level impacts on psychotic disorders. We sought to examine changes in health service use and incident cases of psychotic disorder following cannabis legalization, during a period of tight restrictions on retail stores and product types. METHODS: We conducted a cross-sectional interrupted time-series analysis using linked population-based health administrative data from Ontario (Canada) from January 2014 to March 2020. We identified psychosis-related outpatient visits, emergency department visits, hospitalizations, and inpatient length of stay, as well as incident cases of psychotic disorders, among people aged 14 to 60 years. RESULTS: We did not find evidence of increases in health service use or incident cases of psychotic disorders over the short-term (17 month) period following cannabis legalization. However, we found clear increasing trends in health service use and incident cases of substance-induced psychotic disorders over the entire observation window (2014-2020). CONCLUSION: Our findings suggest that the initial period of tight market restriction following legalization of non-medical cannabis was not associated with an increase in health service use or frequency of psychotic disorders. A longer post-legalization observation period, which includes expansion of the commercial cannabis market, is needed to fully understand the population-level impacts of non-medical cannabis legalization; thus, it would be premature to conclude that the legalization of non-medical cannabis did not lead to increases in health service use and incident cases of psychotic disorder.

The Impacts of Selling Alcohol in Grocery Stores in Ontario, Canada: A Before-After Study.

OBJECTIVE: From 2015 to 2019, the Government of Ontario expanded privatized sales of alcohol, licensing 450 grocery stores to sell beer, cider, and wine. The impacts of a nearby grocery store gaining an alcohol license on adults' alcohol use in Ontario are examined, including whether impacts differed by gender. METHOD: Data from 2015-2019 Canadian Community Health Survey participants in Ontario (age ≥ 20 years), living within 1,000 m and 1,500 m of grocery stores that gained a license to sell alcohol and propensity-matched controls were included (1,000 m n = 14,052, 1,500 m n = 30,486). Alcohol use outcomes included past-7-day number of standard drinks consumed, near-daily drinking (≥4 days/week), and heavy drinking (5+ drinks in men/4+ in women, at least once/month). Gender-specific difference-in-differences (DiD) analyses compared changes in alcohol use before and after intervention in intervention and control populations. RESULTS: Decreases in past-7-day drinks, near-daily drinking, and heavy drinking were observed after intervention in both intervention and control populations. At the 1,000 m level, adjusted DiD analyses showed past-7-day drinking in women (risk ratio = 1.21, 95% CI [0.88, 1.60]) and heavy drinking in men (odds ratio = 1.38, 95% CI [0.92, 2.08]) had effect sizes above 1, a relative increase over controls, although confidence intervals crossed 1. Findings did not indicate significant differences in alcohol use in intervention relative to controls for other alcohol use measures and at 1,500 m. CONCLUSIONS: Findings suggest no association between a partial alcohol deregulation initiative in Ontario and alcohol use from 2015 to 2019. It is important to monitor the impacts on alcohol use over time as further alcohol deregulation plans in Ontario and other jurisdictions are considered.

Mortality in adolescents and young adults following a first presentation to the emergency department for alcohol.

BACKGROUND AND METHODS: We conducted a population-based, retrospective cohort study of first-time emergency department (ED) visits in adolescents and young adults (AYA) due to alcohol and compared mortality to AYA with nonalcohol ED visits between 2009 and 2015 using standardized all-cause mortality ratios (age, sex, income, and rurality). We described the cause of death for AYA and examined the association between clinical factors and mortality rates in the alcohol cohort using proportional hazard models. RESULTS: A total of 71,776 AYA had a first-time ED visit due to alcohol (56.1% male, mean age 20.7 years) between 2009 and 2015, representing 3.3% of the 2,166,838 AYA with an ED visit in this time period. At 1 year, there were 2396 deaths, 248 (10.3%) following an ED visit related to alcohol. First-time alcohol ED visits were associated with a threefold higher risk in mortality at 1 year (0.35% vs. 0.10%, adjusted hazard ratio [aHR] 3.07, 95% confidence interval [CI] 2.69-3.51). Mortality was associated with age 25-29 years (aHR 3.88, 95% CI 2.56-5.86), being male (aHR 1.98, 95% CI 1.49-2.62), having a history of mental health or substance use (aHR 3.22, 95% CI 1.64-6.32), cause of visit being withdrawal/dependence (aHR 2.81, 95% CI 1.96-4.02), and having recurrent ED visits (aHR 1.97, 95% CI 1.27-3.05). Trauma (42.7%), followed by poisonings from drugs other than opioids (38.3%), and alcohol (28.6%) were the most common contributing causes of death. CONCLUSION: Incident ED visits due to alcohol in AYA are associated with a high risk of 1-year mortality, especially in young adults, those with concurrent mental health or substance use disorders, and those with a more severe initial presentation. These findings may help inform the need and urgency for follow-up care in this population.