Population-based comparison of cancer survival outcomes in patients with and without psychiatric disorders.

BACKGROUND: Individuals with psychiatric disorders (PD) have a high prevalence of tobacco use. Patients with PD also potentially receive substandard care in comparison to the general population. Previous research has shown that individuals with PD have a decreased risk of receiving a tobacco related (TR) cancer diagnosis. To further assess this trend, this study assesses the survival of patients with a TR cancer with or without a PD. MATERIALS AND METHODS: Our study utilized multiple databases, with methods described elsewhere,6 to identify people in British Columbia that have been diagnosed with psychiatric disorders and appendicitis (our control group). From these groups, we selected individuals who also had a TR cancer. We subsequently extracted information pertaining to these patients from these databases. RESULTS: Thirty-nine thousand eight hundred forty-one patients with cancer were included in our study. Analyses of these patients were controlled for by age, gender, cancer type and diagnosis year. This analysis displayed shorter survival time among patients who were diagnosed with depression (HR = 1.16; p = 0.01; 95% CI: 1.04-1.29), schizophrenia (HR = 1.62; p < 0.01; 95% CI: 1.43-1.84), or bipolar disorder (HR = 1.35; p < 0.01; 95% CI: 1.12-1.64) compared to the cancer patients without a PD, all of which were statistically significant. People that were diagnosed with anxiety disorders did not have a survival time that was significantly different from our control population (HR = 1.07; p = 0.22; 95% CI: 0.96-1.19). CONCLUSIONS: Individuals with PD, except for those with anxiety, were found to have a shorter survival time following diagnosis with a TR cancer as compared to our control group. We hypothesize several factors, which may account for this statistically significant difference: (1) delayed diagnosis, (2) poor access to care, (3) poor assessment or follow-up, or (4) physician beliefs of poor treatment adherence.

Associations Between Canada's Cannabis Legalization and Emergency Department Presentations for Transient Cannabis-Induced Psychosis and Schizophrenia Conditions: Ontario and Alberta, 2015-2019.

OBJECTIVE: Cannabis legalization in many jurisdictions worldwide has raised concerns that such legislation might increase the burden of transient and persistent psychotic illnesses in society. Our study aimed to address this issue. METHODS: Drawing upon emergency department (ED) presentations aggregated across Alberta and Ontario, Canada records (April 1, 2015-December 31, 2019), we employed Seasonal Autoregressive Integrated Moving Average (SARIMA) models to assess associations between Canada's cannabis legalization (via the Cannabis Act implemented on October 17, 2018) and weekly ED presentation counts of the following ICD-10-CA-defined target series of cannabis-induced psychosis (F12.5; n = 5832) and schizophrenia and related conditions ("schizophrenia"; F20-F29; n = 211,661), as well as two comparison series of amphetamine-induced psychosis (F15.5; n = 10,829) and alcohol-induced psychosis (F10.5; n = 1,884). RESULTS: ED presentations for cannabis-induced psychosis doubled between April 2015 and December 2019. However, across all four SARIMA models, there was no evidence of significant step-function effects associated with cannabis legalization on post-legalization weekly ED counts of: (1) cannabis-induced psychosis [0.34 (95% CI -4.1; 4.8; P = 0.88)]; (2) schizophrenia [24.34 (95% CI -18.3; 67.0; P = 0.26)]; (3) alcohol-induced psychosis [0.61 (95% CI -0.6; 1.8; P = 0.31); or (4) amphetamine-induced psychosis [1.93 (95% CI -2.8; 6.7; P = 0.43)]. CONCLUSION: Implementation of Canada's cannabis legalization framework was not associated with evidence of significant changes in cannabis-induced psychosis or schizophrenia ED presentations. Given the potentially idiosyncratic rollout of Canada's cannabis legalization, further research will be required to establish whether study results generalize to other settings.

Systematic Review of Cannabis Use and Risk of Occupational Injury.

Aim: A range of nations, including countries of the European Union, Australia, and the Americas have recently implemented or proposed reforms to how they control cannabis use, thereby departing from traditional approaches of criminal prohibition that have dominated throughout most of the twentieth century. Given these policy developments and the widespread global use of cannabis, it is critically important to understand the possible risks associated with cannabis use in relation to major societal harms. Methods: This systematic review investigates the potential link between cannabis use and occupational injury. Consequently, it appraises all available current literature from five databases, following Cochrane and PRISMA guidelines. Results: Seven of the 16 reviewed studies show evidence supporting a positive association between cannabis use and occupational injury. One study shows evidence supporting a negative association and the remaining eight studies show no evidence of a significant relation. None of the studies assessed cannabis-related impairment. Only three of the reviewed studies show clear evidence that cannabis use preceded the occupational-injury event. Conclusion: The current body of evidence does not provide sufficient evidence to support the position that cannabis users are at increased risk of occupational injury. Further, the study quality assessment suggests significant biases in the extant literature are present due to potential confounding variables, selection of participants, and measurement of exposures and outcomes. Future high-quality evidence will be needed to elucidate the relation between cannabis use and occupational injury.

Brain dopamine neurone 'damage': methamphetamine users vs. Parkinson's disease - a critical assessment of the evidence.

The objective of this review is to evaluate the evidence that recreational methamphetamine exposure might damage dopamine neurones in human brain, as predicted by experimental animal findings. Brain dopamine marker data in methamphetamine users can now be compared with those in Parkinson's disease, for which the Oleh Hornykiewicz discovery in Vienna of a brain dopamine deficiency is established. Whereas all examined striatal (caudate and putamen) dopamine neuronal markers are decreased in Parkinson's disease, levels of only some (dopamine, dopamine transporter) but not others (dopamine metabolites, synthetic enzymes, vesicular monoamine transporter 2) are below normal in methamphetamine users. This suggests that loss of dopamine neurones might not be characteristic of methamphetamine exposure in at least some human drug users. In methamphetamine users, dopamine loss was more marked in caudate than in putamen, whereas in Parkinson's disease, the putamen is distinctly more affected. Substantia nigra loss of dopamine-containing cell bodies is characteristic of Parkinson's disease, but similar neuropathological studies have yet to be conducted in methamphetamine users. Similarly, it is uncertain whether brain gliosis, a common feature of brain damage, occurs after methamphetamine exposure in humans. Preliminary epidemiological findings suggest that methamphetamine use might increase risk of subsequent development of Parkinson's disease. We conclude that the available literature is insufficient to indicate that recreational methamphetamine exposure likely causes loss of dopamine neurones in humans but does suggest presence of a striatal dopamine deficiency that, in principle, could be corrected by dopamine substitution medication if safety and subject selection considerations can be resolved.

Association Between Socioeconomic Status and Access to Care and Quitting Smoking With and Without Assistance.

INTRODUCTION: Socio-economic disparities in smoking rates persist, in Ontario, despite public health care and universal tobacco control policies. Mechanisms for continuing disparities are not fully understood. Unequal access or utilization of assistance for cessation may contribute. The objective of this research was to use longitudinal data on smokers to examine the associations between socioeconomic status (SES) and access to care measures and assisted and unassisted quit attempts. METHODS: Data were taken from 3578 smokers with at least one follow-up interview participating in the Ontario Tobacco Survey (OTS). Multinomial regression models with imputed missing values were run for each measure of SES and access to care to assess the association with quitting behavior and use of assistance, unadjusted and while adjusting for smoking history and demographic covariates. RESULTS: Adjusted analyses found smokers living in areas with the lowest ethnic concentration were more likely to make an assisted quit attempt compared to unassisted quitting (RR = 1.64; 95% CI = 1.08-2.50) or making no quit attempt (RR = 1.65; 95% CI = 1.15-2.37). Smokers who reported visiting a doctor in the previous 6 months were more likely to quit with assistance versus unassisted compared to those not visiting a doctor, whether they were advised (RR = 1.89, 95% CI = 1.43-2.48) or not advised to quit (OR = 1.32, 95% CI = 1.01-1.74). Similar results were seen when comparing assisted quit attempts with no quit attempts. CONCLUSIONS: Adjusted analyses showed that quitting with assistance was unrelated to measures of SES except ethnic concentration. Physician intervention with patients who smoke is important for increasing assisted quit attempts. IMPLICATIONS: For most measures of SES there were no significant associations with either assisted or unassisted quitting adjusting for demographic and smoking history. Smokers who live in areas with the lowest ethnic concentration were most likely to use assistance as were smokers who visited their doctor and were advised to quit smoking. Interventions to increase the delivery of effective quitting methods in smokers living in areas with high ethnic concentrations and to increase physician compliance with asking and advising patients to quit may increase assisted quit attempts.

Release from drinking-age restrictions is associated with increases in alcohol-related motor vehicle collisions among young drivers in Canada.

BACKGROUND: Alcohol-related motor vehicle collisions (MVCs) are a key concern in current international debates about the effectiveness of minimum legal drinking age (MLDA) laws, but the majority of this literature is based on natural experiments involving MLDA changes occurring 2-4 decades ago. METHODS: A regression-discontinuity approach was used to estimate the relation between Canadian drinking-age laws and population-based alcohol-related MVCs (n=50,233) among drivers aged 15-23years in Canada. RESULTS: In comparison to male drivers slightly younger than the MLDA, those just older had immediate and abrupt increases in alcohol-related MVCs of 40.6% (95% CI 25.1%-56.6%; P<0.001) in Ontario; 90.2% (95% CI 7.3%-171.2%; P=0.033) in Manitoba; 21.6% (95% CI 8.5%-35.0%; P=0.001) in British Columbia; and 27.3% (95% CI 10.9%-44.5%; P=0.001) in Alberta; but also an unexpected significant decrease in the Northwest Territories of -102.2% (95% CI -120.7%-74.9%; P<0.001). For females, release from MLDA restrictions was associated with increases in alcohol-related MVCs in Ontario [34.2% (95% CI 0.9%-68.0%; P=0.044)] and Alberta [82.2% (95% CI 41.1%-125.1%; P<0.001)]. Nationally, in comparison to male drivers slightly younger than the legislated MLDA, male drivers just older had significant increases immediately following the MLDA in alcohol-related severe MVCs [27.0% (95% CI 12.6%-41.7%, P<0.001)] and alcohol-related fatal MVCs [53.4% (95% CI 2.4%-102.9%, P=0.04)]. CONCLUSIONS: Release from Canadian drinking-age restrictions appears to be associated with immediate increases in alcohol-related fatal and non-fatal MVCs, especially among male drivers.

Health profiles of clients in substance abuse treatment: a comparison of clients dependent on alcohol or cocaine with those concurrently dependent.

UNLABELLED: The purpose of this study was to assess whether, among clients receiving substance abuse treatment (n = 616), those dependent on alcohol or cocaine differed significantly from those concurrently dependent on both drugs in terms of physical, mental, social, and economic harms as well as substance use behaviors. METHODS: Clients from five substance abuse treatment agencies presenting with a primary problem of cocaine or alcohol were classified into three groups as dependent on: (1) alcohol alone, (2) cocaine alone, or (3) both cocaine and alcohol (i.e. concurrent dependence). Participants completed a self-administered questionnaire that included details of their drug and alcohol use, physical health, mental health, social health, economic health, and demographic characteristics. RESULTS: The concurrent group drank similar amounts of alcohol as those in the alcohol group and used similar amounts of cocaine as the cocaine group. The alcohol group had significantly (p < .05) poorer health profiles than the concurrent group across most variables of the four health domains. An exception was significantly more accidental injuries (p < .05) in the alcohol group. In both bivariate and multivariate analyses, the concurrent group had significantly (p < .05) more accidental injuries, violence, and overdoses than the cocaine group. As well, the concurrent group had significantly (p < .05) higher scores on the anxiety and sexual compulsion scales than the cocaine group, controlling for demographic variables. CONCLUSION: These findings can aid health care professionals to better respond to issues related to concurrent dependence of cocaine and alcohol.

Marijuana use and risk of lung cancer: a 40-year cohort study.

PURPOSE: Cannabis (marijuana) smoke and tobacco smoke contain many of the same potent carcinogens, but a critical-yet unresolved-medical and public-health issue is whether cannabis smoking might facilitate the development of lung cancer. The current study aimed to assess the risk of lung cancer among young marijuana users. METHODS: A population-based cohort study examined men (n = 49,321) aged 18-20 years old assessed for cannabis use and other relevant variables during military conscription in Sweden in 1969-1970. Participants were tracked until 2009 for incident lung cancer outcomes in nationwide linked medical registries. Cox regression modeling assessed relationships between cannabis smoking, measured at conscription, and the hazard of subsequently receiving a lung cancer diagnosis. RESULTS: At the baseline conscription assessment, 10.5 % (n = 5,156) reported lifetime use of marijuana and 1.7 % (n = 831) indicated lifetime use of more than 50 times, designated as "heavy" use. Cox regression analyses (n = 44,284) found that such "heavy" cannabis smoking was significantly associated with more than a twofold risk (hazard ratio 2.12, 95 % CI 1.08-4.14) of developing lung cancer over the 40-year follow-up period, even after statistical adjustment for baseline tobacco use, alcohol use, respiratory conditions, and socioeconomic status. CONCLUSION: Our primary finding provides initial longitudinal evidence that cannabis use might elevate the risk of lung cancer. In light of the widespread use of marijuana, especially among adolescents and young adults, our study provides important data for informing the risk-benefit calculus of marijuana smoking in medical, public-health, and drug-policy settings.

Effects of the minimum legal drinking age on alcohol-related health service use in hospital settings in Ontario: a regression-discontinuity approach.

OBJECTIVES: We assessed the impact of the minimum legal drinking age (MLDA) on hospital-based treatment for alcohol-related conditions or events in Ontario, Canada. METHODS: We conducted regression-discontinuity analyses to examine MLDA effects with respect to diagnosed alcohol-related conditions. Data were derived from administrative records detailing inpatient and emergency department events in Ontario from April 2002 to March 2007. RESULTS: Relative to youths slightly younger than the MLDA, youths just older than the MLDA exhibited increases in inpatient and emergency department events associated with alcohol-use disorders (10.8%; P = .048), assaults (7.9%; P < .001), and suicides related to alcohol (51.8%; P = .01). Among young men who had recently crossed the MLDA threshold, there was a 2.0% increase (P = .01) in hospitalizations for injuries. CONCLUSIONS: Young adults gaining legal access to alcohol incur increases in hospital-based care for a range of serious alcohol-related conditions. Our regression-discontinuity approach can be used in future studies to assess the effects of the MLDA across different settings, and our estimates can be used to inform cost-benefit analyses across MLDA scenarios.

Association between use of contraband tobacco and smoking cessation outcomes: a population-based cohort study.

BACKGROUND: High tobacco prices, typically achieved through taxation, are an evidence-based strategy to reduce tobacco use. However, the presence of inexpensive contraband tobacco could undermine this effective intervention by providing an accessible alternative to quitting. We assessed whether the use of contraband tobacco negatively affects smoking cessation outcomes. METHODS: We evaluated data from 2786 people who smoked, aged 18 years or older, who participated in the population-based longitudinal Ontario Tobacco Survey. We analyzed associations between use of contraband tobacco and smoking cessation outcomes (attempting to quit, 30-d cessation and long-term cessation at 1 yr follow-up). RESULTS: Compared with people who smoked premium or discount cigarettes, people who reported usually smoking contraband cigarettes at baseline were heavier smokers, perceived greater addiction, identified more barriers to quitting and were more likely to have used pharmacotherapy for smoking cessation. People who smoked contraband cigarettes were less likely to report a period of 30-day cessation during the subsequent 6 months (adjusted relative risk [RR] 0.23, 95% confidence interval [CI] 0.09-0.61) and 1 year (adjusted RR 0.30, 95% CI 0.14-0.61), but they did not differ significantly from other people who smoked regarding attempts to quit (at 6 mo, adjusted RR 0.74, 95% CI 0.43-1.20) or long-term cessation (adjusted RR 0.24, 95% CI 0.04-1.34). INTERPRETATION: Smoking contraband cigarettes was negatively associated with short-term smoking cessation. Access to contraband tobacco may therefore undermine public health efforts to reduce the use of tobacco at the population level.

Alcohol use disorders and risk of Parkinson's disease: findings from a Swedish national cohort study 1972-2008.

BACKGROUND: Alcohol has been suggested to be either protective of, or not associated with Parkinson's disease (PD). However, experimental animal studies indicate that chronic heavy alcohol consumption may have dopamine neurotoxic effects relevant for PD. We studied the association between diagnosed alcohol use disorders and PD. METHODS: All individuals in Sweden admitted with a diagnosis of an alcohol use disorder or appendicitis (reference group) between January 1, 1972 and December 31, 2008 were identified through the Swedish National Inpatient Register, and followed for up to 37 years for a diagnosis of PD. We estimated hazard ratios (HR) with 95% confidence intervals (CI) and adjusted for age and sex. RESULTS: We found 1,741 (0.3%) cases of PD in the cohort of 602,930 individuals, 1,083 (0.4%) among those admitted with an alcohol use disorder and 658 (0.2%) of the individuals admitted with appendicitis. The mean follow-up time was 13.6 and 17.1 years, respectively. The HR for PD associated with an alcohol use disorder was 1.38 (CI 1.25-1.53) adjusted for age and sex. When the risk was estimated in age groups for first hospital admission with PD the highest risk was observed in the lowest age group, ≤44, HR 2.39 (0.96-5.93), adjusted for age at exposure and sex. CONCLUSIONS: A history of an alcohol use disorder conferred an increased risk of admission with a diagnosis of Parkinson's disease in both women and men. In particular, the risk seemed higher at lower ages of first admission with Parkinson's disease.

Canada's cannabis legalization and adult crime patterns, 2015-2021: A time series study.

BACKGROUND AND AIM: A central goal of the Cannabis Act (October 17, 2018) - Canada's national cannabis legalization framework - aimed to reduce cannabis-related criminalization and consequent impact on the Canadian criminal justice system. We assessed whether Canada's cannabis legalization was associated with changes in adult police-reported cannabis-related, property, or violent criminal incidents. DESIGN: Seasonal Autoregressive Integrated Moving Average (SARIMA) time series models evaluated relations between legalization and adult cannabis-related, property, and violent crimes, using criminal incident data from the Canadian Uniform Crime Reporting Survey (UCR-2; January 1, 2015-December 31, 2021). PRIMARY SAMPLE: National police-reported adult cannabis-related offenses (n = 247,249), property crimes (n = 2,299,777), and violent crimes (n = 1,903,762). FINDINGS: Implementation of the Cannabis Act was associated with decreases in adult police-reported cannabis-related offenses: females, -13.2 daily incidents (95% CI, -16.4; -10.1; p < 0.001) - a reduction of 73.9% [standard error (se), 30.6%]; males, -69.4 daily offenses (95% CI, -81.5; -57.2; p < 0.001) - a drop of 83.2% (se, 21.2%). Legalization was not associated with significant changes in the adult property-crime or violent-crime series. CONCLUSIONS: Our findings suggest that Canada's cannabis legalization was successful in reducing cannabis-related criminalization among adults. There was also a lack of evidence for spillover effects of cannabis legalization on adult property or violent crimes.

Impact of Canada's cannabis legalisation on youth emergency department visits for cannabis-related disorders and poisoning in Ontario and Alberta, 2015-2019.

INTRODUCTION: Although there is momentum towards legalising adult recreational cannabis use worldwide, the extent of youth cannabis-related harm associated with legalisation is still uncertain. The current study aimed to assess whether the initial implementation of Canada's cannabis legalisation (via the Cannabis Act) on 17 October 2018 might be associated with youth harm, as assessed by emergency department visits for cannabis-related disorders/poisoning. METHODS: We used Ontario and Alberta, Canada emergency department data from 1 April 2015 to 31 December 2019. We identified all cannabis-related disorders/poisoning (ICD-10 CA: F12.X, T40.7) emergency department visits of youth (n = 13,615), defined as patients younger than the minimum legal cannabis sales age (18 years, Alberta; 19 years, Ontario). Seasonal Autoregressive Integrated Moving Average (SARIMA) models were employed to assess the impact of legalisation on weekly counts of cannabis-related harms. RESULTS: The final SARIMA intervention (step) parameter indicated a post-legalisation increase of 14.7 (95% confidence interval [CI] 5.0; 24.3, p < 0.01) weekly youth cannabis-related disorder/poisoning presentations to Ontario/Alberta emergency department settings, equivalent to an increase of 20.0% (95% CI 6.2%; 33.9%). There was no evidence of associations between cannabis legalisation and comparison series of youth alcohol, opioid or appendicitis emergency department episodes. DISCUSSION/CONCLUSION: Our findings require replication and extension but are consistent with the possibility that the implementation of the Cannabis Act was associated with an increase in youth cannabis-related presentations to Ontario/Alberta emergency departments.

Canada's cannabis legalization and police-reported cannabis-related criminal incidents among youth, 2015-2021.

BACKGROUND: We previously reported that the 2018 Canadian Cannabis Act, allowing youth to possess up to 5 g dried cannabis or equivalent for personal use/sharing, was associated with short-term (76 days) post-legalization reduction in police-reported cannabis-related crimes among youth. To establish whether the change might be sustained, we now estimate this association during a much longer time period by including an additional three years of post-legalization data. METHODS: Using national daily police-reported criminal incident data from January 1, 2015-December 31, 2021 from the Canadian Uniform Crime Reporting Survey (UCR-2), the study employed Seasonal Autoregressive Integrated Moving Average (SARIMA) time series models to assess the associations between legalization and youth (12-17 years) cannabis-related offenses (male, n = 34,508; female, n = 9529). RESULTS: Legalization was associated with significant reductions in both male and female police-reported cannabis-related offenses: females, 4.04 daily incidents [95% confidence interval (CI), 3.08; 5.01], a 62.1% decrease [standard error (se), 34.3%]; males, 12.42 daily offenses (95% CI, 8.99; 15.86), a reduction of 53.0% (se, 22.7%). There was no evidence of associations between cannabis legalization and patterns of property or violent crimes. CONCLUSIONS: Results suggest that the impact of the Cannabis Act on reducing cannabis-related youth crimes is sustained, supporting the Act's objectives to reduce cannabis-related criminalization among youth and associated effects on the Canadian criminal justice system.

First-generation immigrants and hospital admission rates for psychosis and affective disorders: an ecological study in Ontario.

OBJECTIVE: The immigrant population in Canada, and particularly in Ontario, is increasing. Our ecological study first assessed if there was an association between areas with proportions of first-generation immigrations and admissions rates for psychotic and affective disorders. Second, this study examined if area-level risks would persist after controlling for area socioeconomic factors in census-derived geographical areas-Forward Sortation Areas (FSAs)-in Ontario. METHODS: Ontario's inpatient admission records from 1996 to 2005 and census data from 2001 were analyzed to derive FSA rates of first admissions for psychotic disorders and affective disorders per 100 000 person-years. Negative binomial regression models were adjusted, first, for FSA age and sex and, second, also for FSA population density and average income. RESULTS: Using age- and sex-adjusted models, admission rates for psychotic disorders were higher in areas with greater proportions of immigrants. These areas were associated with lower admission rates for affective disorders. When FSA average income and population density were added to the models, the influence of immigrants was attenuated to nonsignificant levels in models predicting psychotic disorders admission rates. However, greater proportions of immigrants remained significantly protective when predicting rates of affective disorders. DISCUSSION: Our study provides insight about the influence of area-level variables on risk of admission for psychotic and affective disorders in high immigrant areas. There is a dearth of current Canadian research on immigrant admission for psychotic disorders at the individual or area level. Future area- and individual-level studies may better identify groups at risk and possible explanations.

Trends in primary methamphetamine-related admissions to youth residential substance abuse treatment facilities in Canada, 2005-2006 and 2009-2010.

OBJECTIVE: During the last decade, methamphetamine use and issues surrounding its toxicity have triggered major concern in the Canadian government, leading to significant changes in drug policy and funding strategies to limit the societal impact of methamphetamine-related harms. This concern appears justified by research which found in 2005-2006 that 21% of all youth admissions to inpatient substance abuse treatment centres in Canada were due primarily to methamphetamine abuse. Given these patterns of treatment use and targeted governmental initiatives, an open question is whether the demand for methamphetamine treatment found in 2005-2006 has decreased. Our study aims to provide follow-up estimates of admissions for 2009-2010, as well as important trend information for these periods. METHOD: We developed a comprehensive list of all Canadian residential youth substance abuse treatment facilities. The executive director of each facility was asked about the site's annual caseload, and the proportion of cases primarily due to methamphetamine abuse within the past 12 months. RESULTS: Our survey data for the periods of 2005-2006 and 2009-2010 show marked reductions in admissions. In 2009-2010, we found that about 6% of all admissions were due primarily to methamphetamine abuse, a substantial drop from the 21% reported in our 2005-2006 study. CONCLUSIONS: Our data show a significant national reduction in methamphetamine-related admissions. Other reports show that methamphetamine-related treatment admissions in the United States and Mexico declined sharply during 2005-2008, reportedly in association with Mexico's methamphetamine precursor chemical controls, raising the possibility that the controls may also be associated with the declines reported here.

Identification of Tobacco-Related Cancer Diagnoses among Individuals with Psychiatric Disorders: A Population-Based Matched Cohort Study Using a Competing Risks Approach from British Columbia.

BACKGROUND: Individuals with psychiatric disorders (PD) have a high prevalence of tobacco use. Therefore, we assessed the hazard of receiving a tobacco-related (TR) cancer diagnosis among individuals with PD. METHODS: Several population-based provincial databases were used to identify individuals in BC diagnosed with depression, schizophrenia, bipolar disorder, anxiety disorders, or multiple PD between 1990 and 2013. A primary population proxy comparison group (appendicitis) was also identified and matched to the psychiatric cohort based on age at cohort entry, gender, year of cohort entry, and postal code. We linked individuals in the cohort and comparison groups with the BC Cancer Registry. Using a competing risks approach, we estimated the effect of having a PD on the risk of receiving a TR cancer diagnosis, in light of the competing risk of mortality. RESULTS: In total, 165,289 patients were included. Individuals with depression (HR = 0.81; p < 0.01; 95% CI: 0.73-0.91), anxiety disorders (HR = 0.84; p = 0.02; 95% CI: 0.73-0.97), or multiple PD (HR = 0.74; p < 0.01; 95% CI: 0.66-0.83) had a statistically significant lower risk of a TR cancer diagnosis compared to the comparison group. Individuals with schizophrenia (HR = 0.86; p = 0.40; 95% CI: 0.62-1.21) or bipolar disorder (HR = 0.58; p = 0.12; 95% CI: 0.29-1.14), however, showed no evidence of a statistically significant difference from the comparison group. INTERPRETATION: We found that individuals with depression, anxiety disorders, or multiple PD diagnoses had a significantly reduced risk of receiving a tobacco-related cancer diagnosis. These results were unexpected and could be explained by individuals with a PD having barriers to a cancer diagnosis rather than a true decreased incidence.

Impacts of Canada's cannabis legalization on police-reported crime among youth: early evidence.

AIMS: Canada's 2018 Cannabis Act allows youth (age 12-17 years) to possess up to 5 g of dried cannabis (or equivalent) for personal consumption/sharing. This study assessed whether the Cannabis Act was associated with changes in police-reported cannabis offences among youth in Canada. DESIGN: Time series model using national daily criminal incident data from January 1, 2015-December 31, 2018 from the Canadian Uniform Crime Reporting Survey (UCR-2). Seasonal autoregressive integrated moving average time series models, stratified by sex, assessed the relations between legalization and youth cannabis-related offences. SETTING: Canada, 2015-2018. CASES: Police-reported cannabis-related offenses among youth age 12-17 years (male, n = 32 178; female, n = 9001). MEASUREMENTS: Outcomes: police-reported cannabis-related crimes, property crimes, and violent crimes. Covariate: calendar-month. FINDINGS: For females, legalization was associated with a step-effect decrease of 4.56 (95% confidence interval [CI] = 3.32, 5.81; P < 0.001) police-reported cannabis-related criminal offences per day, an effect equivalent to a 64.6% (standard error [SE] = 33.5%) reduction. For males, legalization was associated with a drop of 12.73 (95% CI = 8.82, 16.64; P < 0.001) cannabis-related offences per day, equaling a decrease of 57.7% (SE = 22.6%). Results were inconclusive as to whether there were associations between cannabis legalization and patterns of property crimes or violent crimes. CONCLUSIONS: Implementation of the Cannabis Act in Canada in 2018 appears to have been associated with decreases of 55%-65% in cannabis-related crimes among male and female youth.

Canada's cannabis legalization and drivers' traffic-injury presentations to emergency departments in Ontario and Alberta, 2015-2019.

BACKGROUND: Worldwide momentum toward legalization of recreational cannabis use has raised a common concern that such policies might increase cannabis-impaired driving and consequent traffic-related harms, especially among youth. The current study evaluated this issue in Canada. METHODS: Utilizing provincial emergency department (ED) records (April 1, 2015-December 31, 2019) from Alberta and Ontario, Canada, we employed Seasonal Autoregressive Integrated Moving Average (SARIMA) models to assess associations between Canada's cannabis legalization (via the Cannabis Act implemented on October 17, 2018) and weekly provincial counts of ICD-10-CA-defined traffic-injury ED presentations. For each province (Alberta/Ontario), SARIMA models were developed on two driver groups: all drivers, and youth drivers (aged 14-17 years in Alberta; 16-18 years, Ontario). RESULTS: There was no evidence of significant changes associated with cannabis legalization on post-legalization weekly counts of drivers' traffic-injury ED visits in: (1) Alberta, all drivers (n = 52,752 traffic-injury presentations), an increase of 9.17 visits (95 % CI -18.85; 37.20; p = 0.52); (2) Alberta, youth drivers (n = 3265 presentations), a decrease of 0.66 visits (95 % CI -2.26; 0.94; p = 0.42); (3) Ontario, all drivers (n = 186,921 presentations), an increase of 28.93 visits (95 % CI -26.32; 84.19; p = 0.30); and (4) Ontario, youth drivers (n = 4565), an increase of 0.09 visits (95 % CI -6.25; 6.42; p = 0.98). CONCLUSIONS: Implementation of the Cannabis Act was not associated with evidence of significant post-legalization changes in traffic-injury ED visits in Ontario or Alberta among all drivers or youth drivers, in particular.

Incidence of Parkinson's disease among hospital patients with methamphetamine-use disorders.

Because methamphetamine exposure to experimental animals can damage brain dopamine neurones, we examined whether hospital patients diagnosed with methamphetamine-related disorders might have greater risk of subsequent admission with a Parkinson's disease diagnosis. This was a population-based cohort study using all statewide inpatient hospital discharge records from July 1, 1990, through June 30, 2000, in California, USA, in which subjects aged at least 50 years were followed for up to 10 years. Individuals with reported methamphetamine-related conditions (n = 1,863; ICD-9 codes 304.4, 305.7, 969.7, and E854.2) were matched on demographic variables and follow-up time with those with primary appendicitis conditions (n = 9,315). The appendicitis group had a Parkinson's disease incidence rate no different than the rate found among members of a large health maintenance organization in California. Cox regression procedures were used to estimate group differences in the rates of receiving a subsequent inpatient diagnosis of Parkinson's disease (ICD-9 332.0). The methamphetamine group showed increased risk of a subsequent admission with Parkinson's disease compared with that of the matched appendicitis group (adjusted hazard ratio = 2.65, 95% CI, 1.17-5.98, P= 0.019). Study limitations include a population limited to hospital admissions, an uncertainty regarding diagnostic validity of the ICD-9 code 332.0 (Parkinson's disease), and a small number of incident cases with suspected Parkinson's disease. We strongly emphasize the preliminary nature of the findings. Nevertheless, these data, requiring replication, provide some evidence that methamphetamine users might be at greater than normal risk for developing Parkinson's disease.