Examining the role that weight perception and social influences have on mental health among youth in the COMPASS study.

PURPOSE: We investigated whether social health mitigates the association between weight perception and anxiety and depression 1 year later in a large sample of Canadian youth in a prospective, gender-specific analysis. METHODS: We used 2 years of linked survey data from 20,485 grade 9-11 students who participated in wave 6 (2017/18) and 7 (2018/19) of the COMPASS study. Mental health outcomes included the Generalized Anxiety Disorder-7 item (GAD-7) scale and the 10-item Centre for Epidemiological Studies Depression Scale Revised (CESD-10-R). Social health encompassed students' perceived relationships with friends, family, teachers, and within schools. Multilevel, prospective, linear models regressed mental health (at wave 7) on social health (at wave 6) and weight perception (at wave 6) while controlling for weight status, ethnicity, and grade (at wave 6). Interaction terms were used to test social health factors as moderators in the association between weight perception and mental health. RESULTS: Overweight perceptions were associated with higher anxiety and depression scores among youth; this was more pronounced among females. Social health was associated with lower anxiety and depression scores. Among females only, an overweight perception had the highest predicted scores for significant depressive symptoms. Among males only, underweight perceptions were associated with higher anxiety scores. No social health factors had moderating effects in females, and only two interactions were significant among males: feeling safe at school had protective associations with anxiety scores among those with underweight perceptions while those with overweight perceptions had higher depression scores when they reported rewarding social relationships. CONCLUSION: Overweight perceptions in all youth, and underweight perceptions in males, predicted anxiety and depression symptoms 1 year later. The role of social health should not be discounted as a means of preventing anxiety and depression in youth, although this study suggests it is not sufficient to protect against adverse associations with overweight perceptions for all youth, and underweight perceptions for males.

Patterns of Cannabis Use among Canadian Youth over Time; Examining Changes in Mode and Frequency Using Latent Transition Analysis.

Background: Historically substance use literature has focused on smoking as the main mode of cannabis consumption, so there are knowledge gaps surrounding current understanding of edibles and vaping. These alternative modes of cannabis use are already common among Canadian youth; however, little is known about how these cannabis use patterns change over time. Methods: This study examined the mode (smoking, eating/drinking, vaping) and frequency of cannabis use among a large sample of Canadian youth who participated in 2017-2018 and 2018-2019 data collection waves of the COMPASS study. Using latent transition analysis, this sample consisting of 18,824 youth in grades 9-12 were categorized into cannabis use classes stratified by sex, and their transition between these classes over the one-year period was examined. Results: Three cannabis use classes were identified (occasional multimode, regular multimode, and smoking) alongside one nonuse class. Among youth who reported cannabis use at baseline, transitioning to a multimode group, and/or increasing frequency of multimode use was likely over the one-year period. Conclusions: These findings may highlight a key leverage point for harm-reduction strategies which aim to prevent cannabis related harms associated with high frequency use.

High School Intramural Participation and Substance Use: A Longitudinal Analysis of COMPASS Data.

BACKGROUND: There is an association between sports participation and substance use. However, there is some evidence that intramural sports in high school may not have the same effect. Therefore, the objective of this research was to examine the longitudinal associations between intramural participation in high school and substance use. Methods: This study used a three-year linked sample (2016-2018) of grade 9 and 10 (ages 13-17) Canadian high school students in the COMPASS (Cannabis use, Obesity, Mental health, Physical activity, Alcohol use, Smoking, Sedentary behavior) study (n = 7,845). Students reported their participation in intramurals over time (consistent, none, initiate, intermittent, and quit) and their substance use behaviors (binge drinking, cannabis use, cigarette use, and e-cigarette use). Mixed effects models were used. Results: 42% of students did not participate in intramurals. For binge drinking, male students who never participated had lower odds (0.66 [0.47-0.93]) compared to consistent intramural participators. Female (3.50 [CI: 1.34-9.16]) and male students (1.97 [1.28-3.02]) who did not participate in any intramurals were more likely to use cannabis than consistent participators. Male students who did not participate were also more likely to use cigarettes (1.81 [1.05-3.12]). No associations were found between intramural participation and e-cigarette use. Conclusion: Intramural participation may be associated with increased binge drinking among male high school students. More promisingly, consistent participation in intramurals may be protective against cannabis use among male and female students and cigarette use among male students.

The association between public health engagement in school-based substance use prevention programs and student alcohol, cannabis, e-cigarette and cigarette use.

OBJECTIVE: This study examined the associations between public health engagement (PHE) in school-based substance use prevention programs and student substance use. For the purposes of this study, PHE refers to any form of collaboration between the local government public health agency and the school to promote the physical and mental health of students. METHODS: Data for this study were collected from the Cannabis, Obesity, Mental health, Physical activity, Alcohol use, Smoking and Sedentary behaviour (COMPASS) study during the 2018/2019 data collection year. Multilevel logistic regression was used to analyze the associations between PHE and student substance use. RESULTS: Data from 84 schools and 42,149 students were included; 70% of schools had PHE in substance use prevention programs. PHE in substance use prevention appears to have had no significant impact on student substance use in our models. When PHE was divided into five methods of engagement, it was found that when public health solved problems jointly with schools, the odds of a student using alcohol or cannabis significantly increased. When schools were split into low- and high-use schools for each substance measured, some methods of PHE significantly decreased the odds of cannabis and cigarette use in high-use schools and significantly increased the odds of alcohol and cannabis use in low-use schools. CONCLUSION: This study highlights the need to develop better partnerships and collaborations between public health and schools, and the importance of ensuring that school-based substance use prevention programs are evidence-based and tailored to the specific needs of schools and students.

RéSUMé: OBJECTIF: L'étude porte sur les associations entre la participation de la santé publique (PSP) aux programmes de prévention de l'usage de substances en milieu scolaire et l'usage de substances par les élèves. Pour les besoins de l'étude, la PSP désigne toute forme de collaboration entre un organisme de santé publique local et une école visant à promouvoir la santé physique et mentale des élèves. MéTHODE: Nos données sont tirées de l'étude COMPASS (étude de cohorte sur l'obésité, la consommation de marijuana, l'activité physique, la consommation d'alcool, le tabagisme et le comportement sédentaire) durant l'année de collecte de données 2018-2019. Les associations entre la PSP et l'usage de substances par les élèves ont été analysées au moyen de régressions logistiques multiniveaux. RéSULTATS: Nous avons inclus les données de 84 écoles et de 42 149 élèves; dans 70 % des écoles, la santé publique participait aux programmes de prévention de l'usage de substances. La PSP à la prévention de l'usage de substances semble n'avoir eu aucun effet significatif sur l'usage de substances par les élèves dans nos modèles. Quand nous avons divisé la PSP en cinq méthodes de participation, nous avons constaté que lorsque la santé publique résolvait les problèmes conjointement avec les écoles, la probabilité qu'une ou un élève consomme de l'alcool ou du cannabis augmentait de façon significative. Quand nous avons divisé les écoles en écoles à faible et à forte consommation pour chaque substance mesurée, certaines méthodes de PSP réduisaient de façon significative les probabilités d'usage de cannabis et de cigarettes dans les écoles à forte consommation et faisaient augmenter de façon significative les probabilités d'usage d'alcool et de cannabis dans les écoles à faible consommation. CONCLUSION: Notre étude fait ressortir le besoin de créer de meilleurs partenariats et collaborations entre la santé publique et les écoles, ainsi que l'importance de s'assurer que les programmes de prévention de l'usage de substances en milieu scolaire reposent sur des données probantes et qu'ils sont adaptés aux besoins particuliers des écoles et des élèves.

Youth perception of difficulty accessing cannabis following cannabis legalization and during the early and ongoing stages of the COVID-19 pandemic: repeat cross-sectional and longitudinal data from the COMPASS study.

BACKGROUND: Very little research has examined how perceptions of cannabis access among underage youth in Canada have changed since cannabis was legalized and since the onset of the COVID-19 pandemic. As such, this paper examines the effect of the early and ongoing stages of the COVID-19 pandemic period on youth perceptions of cannabis access over time since the onset of the Cannabis Act in 2018 in a large sample of Canadian youth. METHODS: Using data from the COMPASS study (T1:2018/19, T2:2019/20, T3:2020/21), we used both repeat cross-sectional data [T1 (n = 38,890), T2 (n = 24,109), and T3 (n = 22,795)] to examine overall trends in perceptions of cannabis access, and sequential cohort longitudinal data [n = 4,677 students linked from T1 to T3] to examine the differential changes in perceptions of cannabis access among students over time. RESULTS: In the cross-sectional sample, the frequency of students reporting that cannabis was easy to access decreased by 26.7% from T1 (51.0%) to T3 (37.4%), although respondents who have used cannabis were more likely to report access was easy. In the longitudinal sample, perceptions of cannabis access being easy increased over time, especially among cannabis users. Perceived ease of access appears to have been slightly impeded during the initial pandemic period but rebounded during the ongoing pandemic period. CONCLUSIONS: While the prevalence of youth reporting that cannabis is easy to access has declined since legalization and throughout the early and ongoing pandemic periods, a substantial number of underage youth continue to report that cannabis is easy to access. This suggest that there is an ongoing need for continued cannabis control efforts to address this issue.

Mental health and cannabis use among Canadian youth: Integrated findings from cross-sectional and longitudinal analyses.

BACKGROUND AND PURPOSE: Using data from two methodologically independent youth research studies in Canada, the Health Behaviour in School-aged Children (HBSC) study and the Cannabis, Obesity, Mental health, Physical activity, Alcohol, Smoking, and Sedentary behaviour (COMPASS) study, the objective of this study was to compare associations between youth's mental health and cannabis use across samples. Using similar indicators in both studies, our goal was to affirm the potential for nationally representative cross-sectional analyses (HBSC) to replicate findings found in a longitudinal non-representative data source (COMPASS), enhancing opportunity for causal inferences. METHODS: Data were collected from grade 9 and 10 Canadian students participating in the 2017/18 HBSC (n=8462) and 2017/18 to 2018/19 waves of COMPASS (n=32,023). Using multivariable Poisson regression models, the strength and statistical significance of the effects of mental health indicators on cannabis use outcomes were estimated within both studies and compared for consistency. Using a 2-year linked sample of students participating in COMPASS, models examining the impact of mental health indicators on cannabis use initiation and maintenance over time were similarly fit using Poisson regression to estimate relative risk. RESULTS: Similar associations between mental health problems and cannabis use were observed in both data sources. The direction, magnitude, and precision of the estimates for restless sleep, loneliness, poor wellbeing, and cannabis use were highly comparable across both studies. Worse mental health was consistently associated with current and lifetime cannabis use among youth. DISCUSSION: Cross-sectional and longitudinal findings from two large methodologically diverse studies in Canada demonstrate a replicable association between indicators of mental health and youth cannabis use. Similarities were identified and two generalizations may be concluded: 1) potentially causal etiological relationships inferred from HBSC data were supported in longitudinal findings based on COMPASS, and 2) longitudinal COMPASS data aligns with nationally representative data from HBSC.

Examining Engagement With Public Health in the Implementation of School-Based Health Initiatives: Findings From the COMPASS Study.

BACKGROUND: Adolescence coincides with the adoption of health behaviors that schools are not necessarily equipped to properly address. Collaboration between schools and external health services such as public health could fill gaps in addressing student health. METHODS: The current study uses student- and school-level survey data from 59 nonprivate secondary schools in Ontario, Canada in year 6 (2017-2018) of the COMPASS study to examine barriers to improving student health, and analyze the effect of public health engagement on student health behaviors. RESULTS: The majority of schools have received resources from their local public health unit, however, less than one third of schools were developing/implementing programs jointly, and 12% of schools reported no engagement. Students had higher odds of better overall mental health, of meeting screen time guidelines, and were less likely to bully others if public health units solved issues together with schools regarding these health behaviors. CONCLUSIONS: There is a notable lack of consistent public health engagement in schools participating in the COMPASS study despite a need for such services. Creating mechanisms to develop and strengthen effective partnerships between schools and external service providers such as public health might alleviate some barriers to implementing health interventions in Ontario secondary schools.

Correction: An examination of the prospective association between physical activity and academic achievement in youth at the population level.

[This corrects the article DOI: 10.1371/journal.pone.0253142.].

A School-Level Examination of the Association between Programs and Policies and Physical Activity Outcomes among Females from the COMPASS Study.

(1) The majority of Canadian youth are not meeting physical activity guidelines, and more female than male youth are falling short of these recommendations. School programs and policies are a viable strategy to improve youth physical activity. However, they may differentially affect female and male activity. This study aimed to examine school-level differences in physical activity outcomes among male and female students and to explore how school programs and policies associate with school-level physical activity outcomes among females. (2) This study used data from 136 schools participating in year 7 (Y7 2018-2019) of the COMPASS study. Data on school programs and policies and on student physical activity were collected. School-level means and percentages for outcomes were calculated and compared between males and females and the impact of physical activity programs and policies on female physical activity outcomes were examined. (3) More males met the guidelines, achieved more strength training days and physical activity minutes compared to females. The number of female varsity sports, community partnerships and fitness ambassadors were all positively and significantly associated with female physical activity. (4) Supportive physical activity environments fostered by offering varsity sports, establishing community partnerships and positive role models may promote physical activity among female youth.

An examination of the prospective association between physical activity and academic achievement in youth at the population level.

Exercise has significant benefits for brain health and this may have downstream learning benefits for youth. However existing studies looking at links between physical activity and academic achievement are limited by relatively small sample sizes and/or cross-sectional designs. The objective of this study is to determine the direction and magnitude of the association between physical activity and academic achievement in a large prospective sample of adolescents. Linear mixed models with random intercepts and multinomial ordinal generalized estimating equations were employed to analyze the prospective relationship between measures of physical activity and academic achievement from the COMPASS study (N = 9,898 linked participant data cases from year 2 (2013-2014) to year 4 (2015-2016)). The linear relationships between minutes of moderate to vigorous physical activity and academic achievement (English: r = -.047, p < .000; Math: r = -.026, p = .008) as well as meeting the national physical activity guidelines and academic achievement (English: est = -.052, p = .004; Math: est = -.052, p = .028) were negative and trivial in magnitude. Organized sport participation showed slight positive associations with academic achievement indices, but these were also of trivial magnitude. In conclusion, the relationship between physical activity and academic achievement was effectively null in this population sample. Advocacy for physical activity programming for adolescent populations may best be undertaken with reference to lack of net academic achievement cost, rather than presence of benefit, or simply with reference to the many other physical and mental health benefits for youth.

The Impact of Changes in Physical Education Class Enrollment on Moderate-to-Vigorous Physical Activity Among a Large Sample of Canadian Youth.

BACKGROUND: Few youth engage in sufficient daily moderate-to-vigorous physical activity (MVPA), and the likelihood of meeting guidelines declines through secondary school. Physical education (PE) can afford youth with opportunities for MVPA. Therefore, the purpose of this study was to investigate the impact of changes in PE enrollment on MVPA and MVPA guideline adherence in Ontario and Alberta secondary students. METHODS: Linked survey data was used from 1514 students who participated in year 3 (2014/2015 baseline) and year 6 (2017/2018 follow-up) of the COMPASS Study. Regression models tested whether changes in PE enrollment predicted changes in self-reported MVPA (minutes) and MVPA guideline adherence from grade 9 (baseline) to grade 12 (follow-up), controlling for sports participation and sociodemographic variables. RESULTS: Students who remained enrolled in PE in grade 12 reported a daily average of 30 minutes more MVPA. Among students meeting MVPA guidelines and enrolled in PE in grade 9, students not taking PE in the current term in grade 12 were less likely to continue to meet guidelines than students currently enrolled in PE (adjusted odds ratio 0.53; 95% confidence interval: 0.36, 0.78; p < .0013). CONCLUSIONS: Findings from this study could inform the future implementation of a mandatory PE credit for upper year secondary students.

Trends in youth e-cigarette and cigarette use between 2013 and 2019: insights from repeat cross-sectional data from the COMPASS study.

OBJECTIVES: E-cigarettes are an increasingly popular product among youth in Canada. However, there is a lack of long-term data presenting trends in use. As such, the objective of this study was to examine trends in e-cigarette and cigarette use across various demographic characteristics between 2013 and 2019 among a large sample of secondary school youth in Canada. METHODS: Using repeat cross-sectional data from a non-probability sample of students in grades 9 to 12, this study explored trends in the prevalence of ever and current e-cigarette use and cigarette smoking between 2013-2014 and 2018-2019 in British Columbia, Alberta, Ontario, and Quebec. Trends in ever and current e-cigarette use and cigarette smoking were studied across demographic variables among students in Ontario. RESULTS: The prevalence of e-cigarette ever and current use was variable across province and increased over time, particularly between 2016-2017 and 2018-2019. In contrast, the prevalence of current cigarette smoking was relatively stable over the study period, decreasing significantly in Alberta and Ontario between 2017-2018 and 2018-2019. In Ontario, the prevalence of ever and current e-cigarette use increased among all grades, both genders, and all ethnicities. CONCLUSION: Consistent with data from the United States, the prevalence of e-cigarette use among our large sample of Canadian youth has increased substantially in a short period of time. Surveillance systems should continue to monitor the prevalence of tobacco use among youth. Additional interventions may be necessary to curb e-cigarette use among Canadian youth.

RéSUMé: OBJECTIFS: Les cigarettes électroniques sont de plus en plus populaires auprès des jeunes au Canada. Il manque cependant de données à long terme sur les tendances de leur usage. C'est pourquoi nous avons cherché à examiner les tendances de l'usage des cigarettes électroniques et des cigarettes selon diverses caractéristiques démographiques entre 2013 et 2019 dans un vaste échantillon de jeunes fréquentant l'école secondaire au Canada. MéTHODE: À l'aide de données transversales répétées d'un échantillon non probabiliste d'élèves de la 9e à la 12e année, l'étude a exploré les tendances de la prévalence de l'usage antérieur et actuel des cigarettes électroniques et des cigarettes entre 2013-2014 et 2018-2019 en Colombie-Britannique, en Alberta, en Ontario et au Québec. Les tendances de l'usage antérieur et actuel des cigarettes électroniques et des cigarettes ont été étudiées pour diverses variables démographiques chez les élèves de l'Ontario. RéSULTATS: La prévalence de l'usage antérieur et actuel des cigarettes électroniques varie selon la province et a augmenté avec le temps, particulièrement entre 2016-2017 et 2018-2019. Par contre, la prévalence de l'usage actuel des cigarettes a été relativement stable sur la période de l'étude et a sensiblement diminué en Alberta et en Ontario entre 2017-2018 et 2018-2019. En Ontario, la prévalence de l'usage antérieur et actuel des cigarettes électroniques a augmenté chez les élèves de toutes les années, des deux sexes et de toutes les origines ethniques. CONCLUSION: Comme pour les données des États-Unis, la prévalence de l'usage des cigarettes électroniques dans notre vaste échantillon de jeunes Canadiens a considérablement augmenté sur une courte période. Les systèmes de surveillance devraient continuer à surveiller la prévalence du tabagisme chez les jeunes. Des interventions supplémentaires pourraient être nécessaires pour freiner l'usage des cigarettes électroniques chez les jeunes Canadiens.

An examination of how age of onset for alcohol, cannabis, and tobacco are associated with school outcomes in grade 12.

INTRODUCTION: Youth substance use prevention is a key public health priority. There is evidence that delaying substance use can improve health outcomes. While substance use is associated with negative outcomes at school, the benefits of delaying substance use on these outcomes are less well understood. METHODS: The current study examined the substance use behaviours and school outcomes of 35,221 grade 12 students in Canada. Students were asked to report when they began using alcohol, cannabis, and tobacco products as well as school outcomes including school connectedness, math and English grades, truancy, and post-secondary aspirations and expectations. Regression models were used to examine the relationship between of age of initiation of alcohol, cannabis, and tobacco use and these outcomes. RESULTS: Students who abstained from substance use throughout high school had higher school connectedness, lower truancy, and higher grades in grade 12 than students who did not. Earlier cannabis use was associated with increased truancy in grade 12. English grades were higher among students who did not use tobacco. Finally, post-secondary educational aspirations and expectations were higher among students who initiated substance use later. CONCLUSION: Grade 12 school outcomes were the best among students who abstained from substance use throughout high school. However, among students who did engage in substance use, school connectedness, truancy, English grades, and educational aspirations and expectations were more favourable among those who initiated substance use at a later age.

Longitudinal associations between bullying and alcohol use and binge drinking among grade 9 and 10 students in the COMPASS study.

OBJECTIVES: Adolescents involved in bullying are at increased risk for alcohol use; however, much of this research has been cross-sectional. The aim of this work was to therefore examine the longitudinal associations between bullying and future alcohol use. METHODS: Data were drawn from the COMPASS study. The current study used a 2-year linked sample of grade 9 and 10 students from 2015 to 2017 (n = 6005). Students were asked to report their involvement with bullying as well as alcohol use and binge drinking behaviours. Generalized estimating equations regression analyses were used to examine the relationship between bullying involvement at baseline and alcohol use and binge drinking at follow-up. RESULTS: Overall, 20% of students in grades 9 and 10 reported involvement in bullying. There was evidence of a modest longitudinal association between bullying and binge drinking. Being a bully or bully-victim at baseline was associated with increased odds of initiating future binge drinking. CONCLUSIONS: Being a bully or bully-victim in grade 9 or 10 was associated with initiating binge drinking within the following 2 years. Targeted alcohol use prevention programming may benefit these groups.

RéSUMé: OBJECTIFS: Les adolescents impliqués dans l'intimidation courent un risque accru de consommation d'alcool. Cependant, une grande partie de cette recherche a été transversale. Cette étude vise à examiner les associations longitudinales entre l'intimidation et la consommation future d'alcool. MéTHODES: Les données provenaient de l'étude COMPASS. La présente étude utilise un échantillon d'élèves de 9e et 10e années qui ont été suivi de 2015 à 2017 (n = 6 005). Les élèves ont été invités à signaler leur implication dans l'intimidation, la consommation d'alcool et la consommation excessive d'alcool. Des modèles d'équations d'estimation généralisées ont servi à examiner la relation entre la participation à l'intimidation au départ, et la consommation d'alcool et la consommation excessive d'alcool occasionnelle dans les deux années suivantes. RéSULTATS: 20 % des élèves de 9e et 10e années ont déclaré avoir été victimes d'intimidation. Il y avait des preuves d'une modeste association longitudinale entre l'intimidation et la consommation excessive d'alcool. Être un intimidateur ou une victime d'intimidation au départ était associé à une probabilité accrue de consommation excessive d'alcool occasionnelle par la suite. CONCLUSION: Être un intimidateur ou victime d'intimidation était associé à une consommation excessive d'alcool occasionnelle deux ans plus tard chez les élèves de la 9e et la 10e année. Des programmes ciblés de prévention de la consommation d'alcool pourraient bénéficier à ces groupes.

A cross-sectional examination of the association between co-ed and gender-specific school intramural programs and intramural participation among a sample of Canadian secondary school students.

Intramurals are an important part of the physical activity offerings in secondary schools; however, it is not well understood how co-ed and gender-specific intramural programs impact intramural participation among male and female students. Therefore, the objective of this research was to examine if the number of co-ed, male-only, and female-only intramurals offered at a school was associated with student participation in intramurals. A large sample of Canadian secondary school students (N = 59,370) completed the COMPASS survey in 2017-2018. School staff reported the number of co-ed, male-only, and female-only intramurals offered at each school. Students reported whether they participated in school intramurals. Hierarchical models were used to assess associations. Intramural participation was marginally higher among male students (36%) than female students (32%; p < 0.0001). Female students attending schools that offered female-only intramurals were 17% (OR 1.17 [95% CI: 1.05-1.30]) more likely to participate. The number of co-ed and male-only intramurals offered were not significantly associated with student participation. We found a positive association between offering female-only intramurals and female intramural participation, highlighting the importance of these programs for female students. Offering female-only intramurals may be a way for schools to improve participation and physical activity levels of female students. More research is needed on the impact of specific sports or activities on male and female student participation.

High school sport participation and substance use: A cross-sectional analysis of students from the COMPASS study.

INTRODUCTION: The objective of this study was to examine the association between participation in school sports and substance use behaviors in both male and female high school students. METHODS: The current study used cross-sectional data from 60,601 students from Year 6 (2017-2018) of the COMPASS study. Students reported their school physical activity participation (none, intramurals only, varsity only, both) and past 30-day substance use (binge drinking, cannabis use, cigarette use, e-cigarette use). Hierarchical logistic regression models predicted the odds of substance use, by sex. RESULTS: 55% of students did not participate in any school sports and 32% reported substance use. Intramurals were negatively associated with cannabis use and cigarette use among all students and e-cigarette use among females. Varsity sports were associated with lower odds of cigarette use among all students and cannabis use among males. In contrast, participating in varsity sports was associated with increased odds of binge drinking and e-cigarette use among all students. Participating in both intramurals and varsity sports was associated with increased odds of binge drinking and e-cigarette use but with decreased odds of cannabis use and cigarette use. CONCLUSIONS: Intramurals were found to be protective against cannabis use and cigarette use among all students and e-cigarette use among females. Although varsity sports were protective against cannabis and cigarette use, they were found to be a risk factor for binge drinking and e-cigarette use. Substance use prevention efforts should be a focus among school varsity sports teams, especially for binge drinking and e-cigarette use.

Environmental Factors of Youth Milk and Milk Alternative Consumption.

Objective: The objective of this research was to determine the school and community characteristics associated with milk and milk alternative (MMA) consumption by Canadian youth. Methods: We analyzed self-reported data from 50,058 Canadian students participating in the 2017-2018 wave of the COMPASS survey. We used logistic and linear regression analyses to identify school- and community-level factors associated with students meeting the MMA guidelines, and factors associated with daily number of MMA servings consumed, respectively. Results: Student-level factors were more strongly associated with MMA consumption than school- and community-level factors. Students who attended schools that provided staff with nutrition training consumed fewer daily servings of MMAs and were less likely to meet MMA guidelines. Students attending schools that received healthy eating grants were more likely to meet MMA guidelines, whereas students attending schools that sold flavored milk in their vending machines were less likely to meet MMA guidelines. Conclusion: Our findings suggest that student-level factors have a stronger association with MMA consumption than school or community factors. Additional research is needed to understand how factors associated with MMA consumption may influence behaviours over time, and how changes to Canada's food guide may impact youth eating habits.

Examining the impact of timing of alcohol use initiation on changes to body weight and weight status among students in the COMPASS study.

Obesity rates among Canadian youth continue to be a concern, as weight issues during adolescence can transfer into adulthood, leading to long-term health problems. Current evidence lacks a consistent relationship between alcohol consumption and weight gain, and there remains a paucity of research examining the effect of alcohol intake on body weight and BMI over time. This study seeks to examine the effect of grade when students are first classified as "current drinker" and "current binge drinker" on weight and weight status (BMI) trajectories. Two waves of 4-year linked longitudinal data (Y1:2012-13 to Y4:2015-16 and Y2:2013-14 to Y5:2016-17) collected from the COMPASS study (a large prospective cohort study examining health behaviours among Canadian high school students), were used to examine alcohol intake and weight gain among students in grade 9 at their respective baseline year (Y1, n = 1180 or Y2, n = 1612). A modest association between alcohol intake and increased body weight was seen in students who reported binge drinking and earlier onset of alcohol consumption (initiation in grade 10), compared to those who never became binge drinkers, or those who started drinking in grade 11 or grade 12. This additional increase was sustained in grade 11 in males but not females. In contrast, those categorized as "current drinkers" showed no significant increases in weight compared to non-drinkers regardless of grade of initiation. More research should investigate the association between binge drinking and weight gain in high school and beyond, specifically in relation to gender, to approach this issue comprehensively.

An examination of how age of onset for alcohol, cannabis, and tobacco are associated with physical activity, screen time and BMI as students are preparing to graduate from high school.

INTRODUCTION: In this study we examined the co-occurrence of alcohol, cannabis, and tobacco among a large cohort of grade 12 students in Canada, and then explored if the age of initiation of these substances was associated with moderate-to-vigorous physical activity (MVPA), screen time, and BMI. METHODS: This cross-sectional study used student-level data from grade 12 students in years 1 to 5 (2012-2016) of the COMPASS study. Random intercept linear regression models were used to examine the impact of age of initiation of alcohol, cannabis, and tobacco use on student average daily physical activity, daily screen time and BMI. RESULTS: Twenty-eight percent of students had only tried one substance with alcohol being the most reported single substance used (25%). The most common co-occurrence was students reporting having tried all three substances (27%). Nineteen percent of students reported no substance use by grade 12.Younger age of first use of alcohol was associated with increased MVPA in grade 12. Earlier initiation of cannabis and tobacco were associated with increased screen time in grade 12. Age of first use of alcohol, cannabis and tobacco were not associated with BMI in grade 12. CONCLUSION: While no specific cut-off age was identified this study indicates that for every year tobacco and cannabis use are delayed among children, there are subsequent reductions to screen time in grade 12. Early initiation of alcohol was associated with increased MVPA in grade 12. Early initiation of alcohol, cannabis and tobacco were not associated with BMI in grade 12.

Estimating how extra calories from alcohol consumption are likely an overlooked contributor to youth obesity. / Estimation des calories supplémentaires liées à la consommation d'alcool comme facteur potentiellement négligé de l'obésité chez les jeunes.

INTRODUCTION: Youth obesity rates in Canada continue to rise. In this study, we produced conservative estimates of the potential excess calories from alcohol use across different alcohol consumption patterns common among Canadian youth to assess whether alcohol use should be considered in future obesity prevention strategies. METHODS: Using data from 10 144 Grade 12 students participating in the COMPASS study (2013/14), we estimated the number of calories consumed per year from alcohol consumption. Our estimates were based on three different generic types of alcoholic beverages, which were grouped according to average calorie content (vodka coolers; beer [5%]; and beer [4%], wine and liquor) across different frequencies of alcohol use and binge drinking. RESULTS: Results indicated high potential caloric intake for students who binge drank, as well as high variability in the estimates for calories consumed based on common consumption patterns for the different beverage types. For instance, 27.2% of students binge drank once per month, meaning they consumed between 6000 and 13 200 calories in one year (equivalent to 0.78 - 1.71 kg of fat). For the 4.9% of students who binge drank twice per week, the total calories in one year would range from 52 000 to 114 400 (equivalent to 6.74 - 14.83 kg of fat). CONCLUSION: Current recommendations for preventing youth obesity do not generally include any consideration of alcohol use. The high prevalence of frequent alcohol consumption and binge drinking by youth in this study and the substantial number of calories contained in alcoholic beverages suggest alcohol use among youth may warrant consideration in relation to youth obesity prevention.

INTRODUCTION: Les taux d'obésité chez les jeunes ne cessent d'augmenter au Canada. Dans cette étude, nous avons réalisé des estimations conservatrices des calories excédentaires susceptibles de découler de la consommation d'alcool en fonction des habitudes de consommation courantes chez les jeunes Canadiens, afin de déterminer si la consommation d'alcool devrait être prise en compte dans les futures stratégies de prévention de l'obésité. MÉTHODOLOGIE: Des données portant sur 10 144 élèves de 12e année ayant participé à l'étude COMPASS (2013-2014) ont été utilisées pour estimer l'apport calorique annuel provenant de la consommation d'alcool. Pour effectuer nos estimations, nous avons classé les boissons alcoolisées en trois catégories, en fonction de leur teneur moyenne en calories (coolers à base de vodka; bière 5 %; bière 4 %, vin et spiritueux) et de la fréquence de consommation et d'abus occasionnel d'alcool (ou hyperalcoolisation rapide). RÉSULTATS: Les résultats ont indiqué un apport calorique potentiel élevé chez les élèves qui s'adonnaient aux abus occasionnels d'alcool, ainsi qu'une forte variabilité dans les estimations de l'apport calorique en fonction des habitudes de consommation courantes associées aux différents types de boisson. Par exemple, 27,2 % des élèves s'adonnaient à un abus occasionnel d'alcool une fois par mois, ce qui représente une consommation de 6 000 à 13 200 calories par année (soit 0,78 à 1,71 kg de gras). Pour les 4,9 % d'élèves qui s'adonnaient à un abus occasionnel d'alcool deux fois par semaine, le nombre de calories consommées en une année se situerait entre 52 000 et 114 400 (soit 6,74 à 14,83 kg de gras). CONCLUSION: Les recommandations en vigueur pour la prévention de l'obésité chez les jeunes ne tiennent généralement pas compte de la consommation d'alcool. Étant donné à la fois les taux élevés de consommation d'alcool et d'abus occasionnels d'alcool fréquents chez les jeunes mis en lumière dans cette étude et la grande quantité de calories que contiennent les boissons alcoolisées, tenir compte de la consommation d'alcool dans les efforts de prévention de l'obésité chez les jeunes serait pertinent.