Age-dependent association of cannabis use with risk of psychotic disorder.

BACKGROUND: Epidemiologic research suggests that youth cannabis use is associated with psychotic disorders. However, current evidence is based heavily on 20th-century data when cannabis was substantially less potent than today. METHODS: We linked population-based survey data from 2009 to 2012 with records of health services covered under universal healthcare in Ontario, Canada, up to 2018. The cohort included respondents aged 12-24 years at baseline with no prior psychotic disorder (N = 11 363). The primary outcome was days to first hospitalization, ED visit, or outpatient visit related to a psychotic disorder according to validated diagnostic codes. Due to non-proportional hazards, we estimated age-specific hazard ratios during adolescence (12-19 years) and young adulthood (20-33 years). Sensitivity analyses explored alternative model conditions including restricting the outcome to hospitalizations and ED visits to increase specificity. RESULTS: Compared to no cannabis use, cannabis use was significantly associated with psychotic disorders during adolescence (aHR = 11.2; 95% CI 4.6-27.3), but not during young adulthood (aHR = 1.3; 95% CI 0.6-2.6). When we restricted the outcome to hospitalizations and ED visits only, the strength of association increased markedly during adolescence (aHR = 26.7; 95% CI 7.7-92.8) but did not change meaningfully during young adulthood (aHR = 1.8; 95% CI 0.6-5.4). CONCLUSIONS: This study provides new evidence of a strong but age-dependent association between cannabis use and risk of psychotic disorder, consistent with the neurodevelopmental theory that adolescence is a vulnerable time to use cannabis. The strength of association during adolescence was notably greater than in previous studies, possibly reflecting the recent rise in cannabis potency.

Youth cannabis use and subsequent health service use for mood and anxiety disorders: A population-based cohort study.

Epidemiologic research suggests a modest association between youth cannabis use and mood and anxiety disorders (MADs). However, current evidence is based mostly on cohort studies using data from the 20th century when cannabis was significantly less potent than today. We linked population-based survey data from 2009 to 2012 with administrative records of health services covered under universal healthcare up to 2017. The cohort included youth aged 12 to 24 years at baseline living in Ontario, Canada with no prior MAD health service use (n = 8,252). We conducted a multivariable Cox model to estimate the association between cannabis use frequency (never,

Cannabis Use Frequency and Cannabis-Related Consequences in High-Risk Young Adults Across Cannabis Legalization.

Importance: A key concern about recreational cannabis legalization is increases in use and adverse consequences, particularly among young adults (aged 18-29 years) who have the highest prevalence of cannabis use, and especially in higher-risk, more vulnerable young adults. However, few longitudinal studies have examined patterns of cannabis consumption in high-risk young adults over the course of legalization. Objective: To examine changes in cannabis use frequency and cannabis-related consequences over recreational cannabis legalization in Canada in a longitudinal sample of high-risk young adults. Design, Setting, and Participants: Longitudinal observational cohort study following young adults in Ontario, Canada, aged 19.5 to 23.0 years who reported regular heavy episodic drinking (65% past-month cannabis use) at enrollment. Participants were surveyed every 4 months for 3 years between February 2017 and February 2020 (3 prelegalization waves, 4 postlegalization waves). Data were analyzed from March to May 2023. Exposures: Recreational cannabis legalization in Canada and 4 potential moderators of change: sex, income, education, and prelegalization cannabis use frequency. Main Outcomes and Measures: Cannabis use frequency and cannabis-related adverse consequences. Results: In a cohort of 619 high-risk young adults (baseline mean [SD] age, 21.0 [1.2] years; 346 female participants [55.9%]), omnibus model testing revealed significant overall decreases in both cannabis use frequency (F = 2.276, 3000.96; P = .03) and cannabis-related consequences (F = 10.436, 3002.21; P < .001) over time, but these changes were substantially moderated by prelegalization frequency (frequency: F = 7.5224, 3021.88; P < .001; consequences: F = 7.2424, 2986.98; P < .001). Follow-up tests showed individuals who used cannabis more frequently prelegalization significantly decreased their use and cannabis-related consequences postlegalization. In contrast, individuals who did not use cannabis prelegalization exhibited a small magnitude increase in frequency over time but nonsignificant changes in cannabis-related consequences. Sex, income, and education did not moderate changes over time. Conclusions and Relevance: In this cohort study of high-risk young adults, individuals using cannabis frequently prelegalization showed significant reductions in use and consequences over time, reflecting an aging out pattern. Small increases in use among participants with no prelegalization use were observed over time, but without parallel changes in cannabis-related consequences. The results did not reveal substantive adverse near-term outcomes across the legalization period, although a within-participants design cannot rule out the possibility of alternative trajectories in the absence of legalization.

Impact Deposition Behavior of Al/B4C Cold-Sprayed Composite Coatings: Understanding the Role of Porosity on Particle Retention.

This study explores the role of porosity in the impact deposition of a ceramic-reinforced metal-matrix (i.e., Al/B4C) composite coating fabricated via cold spraying. The Johnson-Holmquist-Beissel constitutive law and the modified Gurson-Tvergaard-Needleman model were used to describe the high strain-rate behavior of the boron carbide and the aluminum metal matrix during impact deposition, respectively. Within a finite element model framework, the Arbitrary Lagrangian-Eulerian technique is implemented to explore the roles of reinforcement particle size and velocity, and pore size and depth in particle retention by examining the post-impact crater morphology, penetration depth, and localized plastic deformation of the aluminum substrate. Results reveal that some degree of matrix porosity may improve particle retention. In particular, porosity near the surface facilitates particle retention at lower impact velocities, while kinetic energy dominates particle retention at higher deposition velocities. Altogether, these results provide insights into the effect of deposition variables (i.e., particle size, impact velocity, pore size, and pore depth) on particle retention that improves coating quality.

Household composition and anxiety symptoms during the COVID-19 pandemic: A population-based study.

INTRODUCTION: Household composition may be an important factor associated with anxiety during the COVID-19 pandemic as people spend more time at home due to physical distancing and lockdown restrictions. Adults living with children-especially women-may be particularly vulnerable to anxiety as they balance additional childcare responsibilities and homeschooling with work. The objective of this study was to examine the association between household composition and anxiety symptoms during the COVID-19 pandemic and explore gender as an effect modifier. METHODS: Data were derived from seven waves of a national online survey of Canadian adults aged 18+ years from May 2020 to March 2021, which used quota sampling by age, gender, and region proportional to the English-speaking Canadian population (n = 7,021). Multivariable logistic and modified least-squares regression models were used. RESULTS: Compared to those living alone, significantly greater odds of anxiety symptoms were observed among single parents/guardians (aOR = 2.00; 95%CI: 1.41-2.84), those living with adult(s) and child(ren) (aOR = 1.39; 95%CI: 1.10-1.76), and those living with adult(s) only (aOR = 1.22; 95%CI: 1.00-1.49). Gender was a significant effect modifier on the additive scale (p = 0.0487) such that the association between living with child(ren) and anxiety symptoms was stronger among men than women. CONCLUSION: Additional tailored supports are needed to address anxiety among adults living with children-especially men-during the COVID-19 pandemic and future infectious disease events.

Age differences in the association between loneliness and anxiety symptoms during the COVID-19 pandemic.

Loneliness and associated mental health problems are of particular concern during the COVID-19 pandemic due to physical distancing and lockdown restrictions. Loneliness is most common among young adults and women during the pandemic, but it is unclear if the association between loneliness and mental health problems, notably anxiety, is strongest in these groups. The objective of this study was to examine whether the association between loneliness and anxiety differed by age and/or gender during the pandemic. We analyzed data from a multi-wave national online survey of Canadians aged 18+ years from May 2020 to March 2021 (n = 7,021). Multivariable modified least-squares regression was used to examine whether the association between loneliness and moderate to severe anxiety symptoms (GAD-7 10+) differed by age and/or gender on the additive scale, controlling for socio-demographic factors, depression, hopefulness, and survey wave. Age significantly moderated the association between loneliness and anxiety symptoms while gender did not. Loneliness was associated with anxiety symptoms for all age groups, but the association was not as strong among those aged 70+ years compared to other age groups. Evidence-based loneliness interventions that target younger adults are needed to mitigate the mental health effects of infectious disease events such as COVID-19.

3D Microstructure-Based Finite Element Simulation of Cold-Sprayed Al-Al2O3 Composite Coatings Under Quasi-Static Compression and Indentation Loading.

This study developed microstructure-based finite element (FE) models to investigate the behavior of cold-sprayed aluminum-alumina (Al-Al2O3) metal matrix composite (MMC) coatings subject to indentation and quasi-static compression loading. Based on microstructural features (i.e., particle weight fraction, particle size, and porosity) of the MMC coatings, 3D representative volume elements (RVEs) were generated by using Digimat software and then imported into ABAQUS/Explicit. State-of-the-art physics-based modeling approaches were incorporated into the model to account for particle cracking, interface debonding, and ductile failure of the matrix. This allowed for analysis and informing on the deformation and failure responses. The model was validated with experimental results for cold-sprayed Al-34 wt.% Al2O3 and Al-46 wt.% Al2O3 metal matrix composite coatings under quasi-static compression by comparing the stress versus strain histories and observed failure mechanisms (e.g., matrix ductile failure). The results showed that the computational framework is able to capture the response of this cold-sprayed material system under compression and indentation, both qualitatively and quantitatively. The outcomes of this work have implications for extending the model to materials design and for applications involving different types of loading in real-world application (e.g., erosion and fatigue).

Anticipating the long-term neurodevelopmental impact of the COVID-19 pandemic on newborns and infants: A call for research and preventive policy.

It is estimated that 116 million children were born worldwide in the first nine months of the COVID-19 pandemic. Given the critical importance of early life for neurodevelopment, and evidence suggesting that prenatal maternal stress and early childhood adversity negatively impact neurodevelopment, it is alarming that many pregnant women and new mothers are experiencing high levels of pandemic-related stress. Research and proactive mental health policy is needed to minimize the impact of the COVID-19 pandemic on the future mental health of a global cohort of newborns and infants.

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.

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.

Loneliness in the COVID-19 pandemic: Associations with age, gender and their interaction.

Loneliness is associated with mental health and thus is of particular concern in the COVID-19 pandemic, due to physical distancing restrictions and shelter-in-place orders. The current study assessed the associations of age, gender and their interaction with loneliness during the COVID-19 pandemic, controlling for other sociodemographic variables. A pooled sample of 3,012 English-speaking Canadian adults aged 18+ years completed a web-based survey in one of three waves between May 8 and June 23, 2020. Multivariable logistic regression was used to examine the associations of loneliness with age and gender controlling for marital status, household income, education, living alone, employment situation, and survey wave. A likelihood ratio test assessed the model with interaction between age and gender included. Approximately 8.4% of the sample reported feeling lonely 5+ days in the past week. The regression model with main effects found greater odds of loneliness among women than men (AOR = 1.76, 95%CI = 1.32, 2.34) and among all age groups younger than 60 years compared to those aged 60+ years (p = 0.002). In the final regression model, a significant interaction effect between age and gender on loneliness was found. The interaction showed that women had greater odds of loneliness than men among those aged 18-29 years (AOR = 3.53, 95%CI = 1.69, 7.37) and 60+ years (AOR = 2.62, 95%CI = 1.33, 5.17). Special consideration of loneliness among younger and older adult women is needed in service planning. Given inconsistencies with pre-pandemic studies, detailed data collected during the current crisis is essential to inform proactive resource allocation to prevent and treat mental health consequences of the pandemic.

Traumatic brain injuries and problem gambling in youth: Evidence from a population-based study of secondary students in Ontario, Canada.

Traumatic brain injury (TBI) is characterized by a change in brain function after an external force or sudden movement to the head. TBI is associated with risk-taking, impulsivity, psychological distress, substance abuse, and violent crime. Previous studies have also linked problem gambling to TBI, but these studies have not controlled for possible confounding variables such as mental health problems and hazardous drinking which are also linked to TBI. This study examines the relationship between problem gambling and TBI among adolescents. Data were obtained from the 2011, 2013 and 2015 cycles of the OSDUHS, a biennial cross-sectional school-based study of children in grades 7 to 12 (N = 9,198). Logistic regression was used to estimate adjusted odds ratios (AOR) in controlled and uncontrolled analyses. Adjusting for sex and grade only, problem gambling was associated with a history of TBI (AOR = 2.8). This association remained significant after adjusting for hazardous drinking and suicidality (AOR = 2.0). In addition, problem gambling had a statistically significant relationship with being male (AOR = 4.7), hazardous drinking (AOR = 4.5), and suicidality (AOR = 3.1). This study provides further data to suggest a link between TBI and problem gambling. However, research is needed on the causal relationship between these variables and the potential implications for treatment and prevention.

Assessing the impact of the 2015 introduction of increased penalties and enhanced public awareness and enforcement activities on texting while driving among adults in Ontario, Canada.

Objective: Texting while driving (TWD) is considered a particularly hazardous form of distracted driving. It is highly prevalent among young drivers, but fewer studies of TWD among adult drivers exist and these prevalence rates may approach those of younger drivers. The effectiveness of measures to prevent distracted driving, and TWD specifically, is unclear. On September 1, 2015, Ontario introduced increased penalties for distracted driving accompanied by public education programs to increase public awareness of the new regulations. Provincial police also introduced enhanced enforcement efforts. The current study examined self-reported TWD in a representative sample of Ontario adults before and after introduction of the new legislation and the enhanced public education and enforcement efforts.Methods: Data were based on telephone interviews with 1,846 respondents who reported having driven in the past year. Data were derived from the 2015-2016 cycles of the Centre for Addiction and Mental Health (CAMH) Monitor, an ongoing cross-sectional telephone survey of adults aged 18+ years in Ontario, Canada. A binary logistic regression analysis of TWD in the previous 30 days was conducted, adjusting for demographic characteristics (sex, age), driving exposure, and introduction of the legislation (before versus after).Results: The proportion of the sample reporting TWD declined significantly from 37.6% before the law was introduced to 24.2% after the law was introduced. The impact appeared to be most pronounced among drivers who reported TWD more frequently. Adjusted odds of TWD declined 42% following introduction of the legislation and associated enhanced public education and enforcement.Conclusions: These results identify a decrease in TWD following the introduction of enhanced penalties with corresponding public education and enforcement efforts, adding to the existing evaluative evidence base to inform transportation safety policy. These results also support the need to examine TWD and its determinants among all age groups.

In-situ SEM observations of ultrasonic cavitation erosion behavior of HVOF-sprayed coatings.

Several typical high-velocity oxy-fuel (HVOF)-sprayed coatings, including WC-10Co4Cr coatings, Co-based coatings, WC-10Co4Cr/Co-based composite coatings, and Fe-based amorphous/nanocrystalline coatings were fabricated, and their cavitation behavior was evaluated in deionized water. Further, in-situ SEM surface observations were used to understand the microstructure of tested coatings. The results show that cavitation erosion initially occurred at pre-existing defects in the coatings. Meanwhile, it was found that cavitation erosion damage of the WC-10Co4Cr/Co-based composite coating, which contained a hard reinforcing phase (WC-10Co4Cr phase) and a soft matrix phase (Co-based phase), preferentially occurred at or around pores and microcracks in the reinforcement, rather than in the defect free matrix. This suggested that defects were a critical contributing factor to cavitation damage of the composite coatings. Furthermore, a mechanism was suggested to explicate the cavitation behavior of composite coatings. The approach of using in-situ SEM surface observations proved to be useful for the analysis of the cavitation mechanism of engineering materials and protective coatings.

Moderate to severe gambling problems and traumatic brain injury: A population-based study.

Traumatic brain injury (TBI) is a common injury characterized by a change in brain function after an external blow to the head and is associated with substance abuse, psychological distress, risk-taking, and impulsivity. Convenience and clinical samples have also linked TBI to problem gambling, but have not ruled out confounding variables such as hazardous drinking and psychological distress. This study examines the relationship between TBI and moderate to severe problem gambling in a general population probability sample controlling for hazardous drinking and psychological distress. The data were obtained from a 2015-2016 cross-sectional general population telephone survey of adults ages 18+from Ontario, Canada (N = 3809). Logistic regression was used to estimate the association as adjusted odds ratios (AOR). Moderate to severe problem gambling was independently associated with a history of TBI after adjusting for potential confounders (AOR: 2.80), and had a statistically significant relationship with psychological distress (AOR = 2.74), hazardous drinking (AOR = 2.69), and lower educational levels (AOR = 0.37). This study provides further data to suggest a link between TBI and moderate to severe problem gambling; however, more research is needed to determine if there is a causal relationship or the potential implications for prevention and treatment.

Defining and measuring health equity effects in research on task shifting interventions in high-income countries: a systematic review protocol.

INTRODUCTION: Task shifting interventions are intended to both deliver clinically effective treatments to reduce disease burden and address health inequities or population vulnerability. Little is known about how health equity and population vulnerability are defined and measured in research focused on task shifting. This systematic review will address the following questions: Among task shifting interventions in high-income settings that have been studied using randomised controlled trials or variants, how are health inequity or population vulnerability identified and defined? What methods and indicators are used to describe, characterise and measure the population's baseline status and the intervention's impacts on inequity and vulnerability? METHODS AND ANALYSIS: Studies were identified through database searches (MEDLINE, Embase, CINAHL, PsycINFO and Web of Science). Eligible studies will be randomised controlled trials published since 2004, conducted in high-income countries, concerning task shifting interventions to treat any disease, in any population that may face health disadvantage as defined by the PROGRESS-Plus framework (place of residence, race/ethnicity/culture/language, occupation, gender/sex, religion, social capital, socioeconomic position, age, disability, sexual orientation, other vulnerable groups). We will conduct independent and duplicate title and abstract screening, then identify related papers from the same programme of research through further database and manual searching. From each programme of research, we will extract study details, and definitions and measures of health equity or population vulnerability based on the PROGRESS-Plus framework. Two investigators will assess the quality of reporting and measurement related to health equity and vulnerability using a scale developed for this study. A narrative synthesis will highlight similarities and differences between the gathered studies and offer critical analyses and implications. ETHICS AND DISSEMINATION: This review does not involve primary data collection, does not constitute research on human subjects and is not subject to additional institutional ethics review or informed consent procedures. Dissemination will include open-access peer-reviewed publication and academic conference presentations.PROSPERO Registration Number CRD42017049959.