Changing eating to manage weight or shape: A cross-sectional and prospective study of the prevalence and correlates in a large Canadian adolescent cohort.

OBJECTIVE: The present study examined reports of changing eating to manage weight/shape over one year among adolescents. It also tested how changing eating for weight/shape was associated with physical activity (resistance training, moderate-to-vigorous physical activity; MVPA) and mental health (depressive symptoms, flourishing), and whether weight perceptions moderated these associations. METHODS: Participants were Canadian adolescents (N = 20,614, Mage ± SD = 14.4 ± 1.3, 52.9% girls) who completed self-report surveys in the 2020-2021 and 2021-2022 waves of the COMPASS study. Separate multilevel models were tested for each outcome. RESULTS: Approximately 30% of adolescents reported changing their eating to manage weight/shape at least once a week. More days of changing eating were associated with significantly higher depressive symptoms and lower flourishing cross-sectionally (b = 0.51, b = -0.27) and over time (b = 0.35, -0.20); the flourishing association over time was weaker for adolescents who perceived themselves as overweight relative to about right. More days of changing eating were also associated with more MVPA and resistance training cross-sectionally (b = 2.81, b = 0.19) and over time (b = 1.28, b = 10). The relationship between changing eating and MVPA over time was stronger for adolescents who perceived themselves as overweight relative to about right; whereas the cross-sectional relationship between changing eating and resistance training was weaker. CONCLUSIONS: Reports of changing eating to manage weight/shape were associated with divergent health outcomes; research into how and to what extreme adolescents are changing eating to manage weight/shape, and identity factors that may contribute to these differences, is warranted.

Attitudes, subjective norms and perceived behavioural control factors influencing Canadian secondary school students' milk and milk alternatives consumption.

OBJECTIVE: The research objectives were to evaluate factors that influence Canadian secondary school students' milk and milk alternatives (MMA) consumption and to explore associations through age and gender lenses. DESIGN: A qualitative design was used, consisting of semi-structured interviews and photo-elicitation methods. Analysis was guided by the Theory of Planned Behaviour (TPB). Deductive and inductive thematic analyses were used to generate themes, charting data based on attributes such as gender and age. SETTING: Interviews were held virtually or via telephone. PARTICIPANTS: Participants were twenty-eight high school students from Ontario, Canada, diverse in terms of gender and age. RESULTS: Both desirable and undesirable beliefs about the health outcomes of consuming MMA were commonly discussed. These included health benefits such as strong bones, muscular strength, and growth, and health consequences like unwanted skin conditions, weight gain, and diseases. While boys and girls associated MMA consumption with muscular strength, boys predominantly considered this favourable, while girls discussed outcomes like unwanted skin conditions and weight gain more often. Adolescents' perspectives on taste/perceived enjoyment, environmentally friendly choices and animal welfare also influenced their MMA preferences. Parental influences were most cited among social factors, which appeared to be stronger during early adolescence. Factors involving cost, time and accessibility affected adolescents' beliefs about how difficult it was to consume MMA. CONCLUSIONS: Recommendations for shifting attitudes towards MMA are provided to address unfavourable beliefs towards these products. Interventions to increase MMA consumption among adolescents should include parents and address cost barriers.

Public health unit engagement in school mental health programs and adolescent mental health during the COVID-19 pandemic: COMPASS, 2018-2022.

BACKGROUND: Public health unit (PHU) engagement in schools is important for promoting wellness in students. We aimed to investigate if PHU engagement with schools may have provided protection against the risk of depression and anxiety in students during the COVID-19 pandemic. METHODS: We used longitudinal data from the Cannabis, Obesity, Mental health, Physical activity, Alcohol use, Smoking and Sedentary behaviour survey between the 2018/19 and 2020/21 academic years. Multilevel models were used to assess the association between PHU engagement with school mental health programs prior to the COVID-19 pandemic and depressive (Center for Epidemiologic Studies Depression scale Revised) and anxiety symptoms (Generalized Anxiety Disorder scale) during the COVID-19 pandemic. RESULTS: The sample included 23 894 students across 104 secondary schools in British Columbia, Alberta, Ontario and Quebec. In confounder-adjusted models, PHU engagement before the pandemic was not associated with student depressive symptoms (B = -0.01, 95% CI = -0.04, 0.02), but was protective against anxiety symptoms (B = -0.03, -0.06, 0.001) during the COVID-19 pandemic. DISCUSSION: The results highlight that PHU engagement with mental health programming in schools was protective against anxiety for students during the COVID-19 pandemic. The findings support the importance of PHU engagement for improving student mental health and pandemic recovery.

Identifying latent classes of physical activity profiles over time among adolescents in Ontario, Canada.

BACKGROUND: Physical activity behaviours are known to be highly correlated. Adolescents who participate in one type of physical activity (e.g., physical education) have a greater likelihood of participating in other physical activities (e.g., organized sports); however, little research has examined participation rates in various physical activity behaviours concurrently. This study identified longitudinal physical activity profiles among secondary school aged youth in Ontario, Canada. METHODS: We used data from the COMPASS Study, a school-based prospective cohort study of adolescents in Canada. Using a repeated measures latent class analysis, Ontario students who participated in grade 9 PE in 2015-16 were analysed through to 2018-19 (n = 1,917). Latent classes were defined by: PE participation, guideline adherence (≥ 60 min/day of moderate to vigorous activity over the last 7 days), and sport participation (varsity, community, and/or intramural). Multinomial logistic regression models were used to examine associations between latent class membership and student characteristics. RESULTS: Three distinct latent classes were identified for females and four were identified for males. These classes were: (1) Guidelines (high probability of guideline adherence; females: 44%; males: 16%), (2) PE & Sports (high probability of PE and sport participation; females: 33%; males: 43%), (3) Guidelines & Sports (high probability of guideline adherence and sport participation; females: 23%; males: 23%;), and (4) Inactive (low probability of all physical activity indicators; males: 18%). Strength training, sleep, and English grade were associated with class membership among females. Ethno-racial identity, weekly spending money, strength training, and English and math grades were associated with class membership among males. CONCLUSIONS: Findings suggest that latent physical activity profiles differ by sex. Guideline adherence was the most common class among females, indicating high levels of independent physical activity, whereas PE & Sport participation was the most common class among males, indicating greater tendency towards organized activities. Additionally, a substantial number of male students were not engaging in any physical activity. Participation in both PE and sports did not necessarily lead to meeting physical activity guidelines, highlighting that these activities alone may not be providing sufficient levels of physical activity that align with current recommendations for Canadian youth.

Adolescents' impairment due to climate anxiety is associated with self-efficacy and behavioral engagement: a cross-sectional analysis in Quebec (Canada).

BACKGROUND: The current understanding of climate anxiety among adolescents is sparse. This study identifies the characteristics of adolescents living in Quebec (Canada) who experience impairments induced by climate anxiety, who have feelings of self-efficacy and who adopt pro-environment behaviors. It also characterizes the association between climate anxiety, feelings of self-efficacy, and environmental actions. METHODS: We used a cross-sectional design to analyze data from the COMPASS study on adolescent health. Participants (n = 45 362) from 113 schools in Quebec (Canada) answered questions about climate anxiety, self-efficacy, behavioral engagement, and several indicators of well-being. Data were analyzed using ordered logistic regressions adjusted for potential confounders (age, gender, school type, material deprivation, etc.). RESULTS: 9% of adolescents reported that thinking about climate change made it difficult to sleep at least sometimes. 6% of adolescents reported that thinking about climate change interfered with their ability to get work or assignments done at least sometimes. Only 34% believed they could do something to address the problem, and 43% tried to reduce their behaviors that contribute to climate change at least sometimes. Adolescents who were boys or who were less anxious experienced less impairment and were less involved in the fight against climate change. Adolescents from less affluent families experienced more difficulty sleeping and interference with work but were not more engaged. Those with stronger school connectedness experienced less impairment and were more often involved in the fight against climate change. Adolescents who felt they could do something about climate change were more likely to try to reduce behaviors that contribute to climate change. CONCLUSION: The findings are useful to identify and support vulnerable groups that are more likely to experience impairment due to climate anxiety. The feeling of climate self-efficacy was not well developed among some groups of adolescents. Improving adolescents' beliefs in their capacity to help address climate change may be a key strategy to promote pro-environmental actions. As the threat of climate change increases, it will be important to follow the evolution of climate anxiety and engagement among adolescents.

Do sociodemographic risk profiles for adolescents engaging in weekly e-cigarette, cigarette, and dual product use differ?

BACKGROUND: E-cigarette use represents a contemporary mode of nicotine product use that may be changing the risk profile of participating adolescents. Understanding differences in sociodemographic characteristics of adolescents engaging in contemporary e-cigarette use and traditional cigarette use is important for effectively developing and targeting public health intervention programs. The objective of this study was to identify and compare sociodemographic risk profiles for exclusive e-cigarette use and dual-product use among a large sample of Canadian youth. METHODS: A survey of 46,666 secondary school students in the 2021-22 wave of the COMPASS study measured frequency of past month e-cigarette and cigarette use as well as age, sex, gender, racial or ethnic background, spending money, relative family affluence, and having one's own bedroom. Rates of cigarette-only, e-cigarette-only, and dual product use were calculated, and separate classification trees were run using the CART algorithm to identify sociodemographic risk profiles for weekly dual-product use and weekly e-cigarette-only use. RESULTS: Over 13% of adolescents used only e-cigarettes at least weekly, 3% engaged in weekly dual e-cigarette and cigarette use, and less than 0.5% used only cigarettes. Available spending money was a common predictor of dual-product and e-cigarette-only use. Gender diverse youth and youth with lower perceived family affluence were at higher risk for dual-product use, while white and multiethnic adolescents were at greater risk of e-cigarette-only use. Two high-risk profiles were identified for e-cigarette-only use and four high-risk profiles were identified for dual product use. CONCLUSIONS: This study used a novel modelling approach (CART) to identify combinations of sociodemographic characteristics that profile high-risk groups for exclusive e-cigarette and dual-product use. Unique risk profiles were identified, suggesting that e-cigarettes are attracting new demographics of adolescents who have not previously been considered as high-risk for traditional cigarette use.

Inequities in sleep duration and quality among adolescents in Canada.

BACKGROUND: Several recent global events may have impacted adolescent sleep and exacerbated pre-existing disparities by social positions (i.e., social roles, identity or sociodemographic factors, and/or group memberships that are associated with power and oppression due to the structures and processes in a given society at given time). Current understanding of sleep among adolescents is critical to inform interventions for a more equitable future, given the short and long-term consequences of inadequate sleep on health and well-being. This study aimed to provide contemporary evidence on sleep disparities by key social positions among adolescents in Canada. METHODS: Cross-sectional analyses were conducted using self-reported data collected during 2020-2021 (the first full school year after the COVID-19 pandemic onset) from 52,138 students (mean [SD] age = 14.9 [1.5]) attending 133 Canadian secondary schools. Multiple regression models were used to test whether sleep quality (how well students slept during past week), duration (weekday, weekend, weighted daily average), and guideline adherence (8-10 h/day) differed by sex and gender, race and ethnicity, and socioeconomic status (SES). RESULTS: Females reported a mean [95% CI] difference of -1.7 [-3.7, 0.4] min/day less sleep on weekdays than males, but 7.1 [4.5, 9.6] min/day more sleep on weekends, resulting in no difference in average daily sleep between males and females. Females were less likely to report good quality sleep compared to males (AOR = 0.57 [0.54, 0.60]). SES followed a generally monotonic trend where higher scores were associated with more sleep on weekdays (Δhighest: lowest = -28.6 [-39.5, -17.6]) and weekends (Δhighest: lowest = -17.5 [-3.8, -31.2]) and greater likelihood of higher sleep quality (AORhighest: lowest = 3.04 [2.35, 3.92]). Relative to White adolescents, weekday and average daily sleep duration were lower among all other racial identities; mean differences ranged from ∼ 5-15 min/day, with Black students reporting the least sleep. CONCLUSIONS: Differences in sleep duration and quality were most profound among adolescents from the lowest and highest SES. Racial disparities were more evident on weekdays. Compensatory weekend sleep appears more pronounced in females than males. Addressing sleep inequities is critical, as a robust predictor of multiple health outcomes.

Using random forest to identify correlates of depression symptoms among adolescents.

PURPOSE: Adolescent depression is a significant public health concern, and studying its multifaceted factors using traditional methods possess challenges. This study employs random forest (RF) algorithms to determine factors predicting adolescent depression scores. METHODS: This study utilized self-reported survey data from 56,008 Canadian students (grades 7-12) attending 182 schools during the 2021/22 academic year. RF algorithms were applied to identify the correlates of (i) depression scores (CESD-R-10) and (ii) presence of clinically relevant depression (CESD-R-10 ≥ 10). RESULTS: RF achieved a 71% explained variance, accurately predicting depression scores within a 3.40 unit margin. The top 10 correlates identified by RF included other measures of mental health (anxiety symptoms, flourishing, emotional dysregulation), home life (excessive parental expectations, happy home life, ability to talk to family), school connectedness, sleep duration, and gender. In predicting clinically relevant depression, the algorithm showed 84% accuracy, 0.89 sensitivity, and 0.79 AUROC, aligning closely with the correlates identified for depression score. CONCLUSION: This study highlights RF's utility in identifying important correlates of adolescent depressive symptoms. RF's natural hierarchy offers an advantage over traditional methods. The findings underscore the importance and additional potential of sleep health promotion and school belonging initiatives in preventing adolescent depression.

School learning modes during the COVID-19 response and pre- to during pandemic mental health changes in a prospective cohort of Canadian adolescents.

PURPOSE: Considerable debate centered on the impact of school closures and shifts to virtual learning on adolescent mental health during the COVID-19 pandemic. We evaluated whether mental health changes differed by school learning modes during the pandemic response among Canadian adolescents and whether associations varied by gender and perceived home life. METHODS: We used prospective survey data from 7270 adolescents attending 41 Canadian secondary schools. Conditional change linear mixed effects models were used to examine learning mode (virtual optional, virtual mandated, in-person, and blended) as a predictor of change in mental health scores (depression [Centre for Epidemiologic Studies - Depression], anxiety [Generalized Anxiety Disorder-7], and psychosocial well-being [Flourishing scale]), adjusting for baseline mental health and covariates. Gender and home life happiness were tested as moderators. Least square means were calculated across interaction groups. RESULTS: Students learning in a blended learning mode had greater anxiety increases relative to their peers in other learning modes. Females learning fully in-person and males learning virtually when optional reported less of an increase in depression scores relative to their gender counterparts in other learning modes. Learning virtually when optional was associated with greater declines in psychosocial well-being in students without happy home lives relative to other learning modes. CONCLUSION: Findings demonstrate the importance of considering gender and home environments as determinants of mental health over the pandemic response and when considering alternative learning modes. Further research is advised before implementing virtual and blended learning modes. Potential risks and benefits must be weighed in the context of a pandemic.

Association Between Diet and Mental Health Outcomes in a Sample of 13,887 Adolescents in Canada.

Introduction: The high prevalence of mental disorders among adolescents calls for community-based and population-level prevention strategies. Diet is an important intervention target for primary prevention of mental disorders among adolescents. We used data from a large longitudinal study of Canadian adolescents (aged 14-18 y) to examine prospective associations between diet and mental health outcomes. Methods: We estimated the effect of diet (ie, consumption of vegetables and fruit and sugar-sweetened beverages [SSBs]) at baseline on depressive symptoms, anxiety symptoms, and psychological well-being (measured by the Center for Epidemiologic Studies Depression Scale-Revised, Generalized Anxiety Disorder 7 scale, and Flourishing Scale, respectively) and at 1-year follow-up in a sample of 13,887 Canadian secondary school students who participated in the 2017-2018 and 2018-2019 cycles of the Cannabis, Obesity, Mental health, Physical activity, Alcohol, Smoking, and Sedentary (COMPASS) behavior study. We applied linear mixed-effects methods informed by a directed acyclic graph. Sensitivity analyses assessed the robustness of the effect estimates to unmeasured confounding variables. Results: Baseline SSB consumption was associated with greater severity of depressive (ß = 0.04; 95% CI, 0.01-0.06) and anxiety (ß = 0.02; 95% CI, 0-0.05) symptoms, particularly among male students, and poorer psychological well-being (ß = -0.03; 95% CI, -0.05 to -0.01) at follow-up. Baseline vegetables and fruit consumption was positively associated with psychological well-being (ß = 0.06; 95% CI, 0.03-0.10) but not other mental health outcomes at follow-up. Conclusion: Our results support the notion that diet should be part of comprehensive mental health prevention and promotion interventions to reduce the prevalence of mental health disorders among adolescents.

Factors associated with prospective changes in weight control intentions among adolescents.

INTRODUCTION: The present study examined predictors of negative changes in weight control intentions from before to during the COVID-19 pandemic among adolescents. METHODS: Participants were Canadian secondary school students enrolled in the COMPASS study and had completed self-report surveys before (T1; 2018/2019 and/or 2019/2020 school year) and during (T2; 2020/2021 and/or 2021/2022) the COVID-19 pandemic (N = 11,869, Mage ± SD = 13.79 years old ± 1.15, 52.89% girls, 45.30% boys, 1.81% gender diverse). Demographic, interpersonal, behavioral, and psychological predictors of weight control intention change from T1 (stay the same weight, not doing anything about weight) to T2 (lose weight, gain weight) were tested using multilevel logistic regressions. RESULTS: Over one-third (37.0%) of adolescents who reported wanting to stay the same weight at T1 changed their intention to lose or gain weight at T2, as did 28.5% of adolescents who reported not wanting to do anything about their weight at T1. Changing weight control intention from "not doing anything about weight" at T1 to weight gain/loss at T2 was associated with resistance training, emotion dysregulation, bullying, social media use, and gender. Changing weight control intention from "stay the same weight" at T1 to weight gain/loss at T2 was associated with gender, perceived financial comfort, social media use, and flourishing. CONCLUSIONS: Results highlight the prevalence of maladaptive weight control intention changes among adolescents, and elucidate related behavioral, interpersonal, demographic, and psychological factors. Findings can inform targeted intervention and prevention strategies to disrupt maladaptive changes in weight control intentions among high-risk subgroups.

Income Inequality and the Odds of Online Gambling Among a Large Sample of Adolescents in Canada.

Consistent evidence points to the detrimental effects of income inequality on population health. Income inequality may be associated with online gambling, which is of concern since gambling is a risk factor for adverse mental health conditions, such as depression and suicide ideation. Thus, the overall objective of this study is to study the role of income inequality on the odds of participating in online gambling. Data from 74,501 students attending 136 schools participating in the 2018/2019 Cannabis, Obesity, Mental health, Physical activity, Alcohol, Smoking, and Sedentary behaviour (COMPASS) survey were used. The Gini coefficient was calculated based on school census divisions (CD) using the Canada 2016 Census linked with student data. We used multilevel modeling to explore the association between income inequality and self-reported participation in online gambling in the last 30 days, while controlling for individual- and area-level characteristics. We examined whether mental health (depressive and anxiety symptoms, psychosocial wellbeing), school connectedness, and access to mental health programs mediate this relationship. Adjusted analysis indicated that a standardized deviation (SD) unit increase in Gini coefficient (OR = 1.17, 95% CI 1.05, 1.30) was associated with increased odds of participating in online gambling. When stratified by gender, the association was significant only among males (OR = 1.12, 95% CI 1.03, 1.22). The relationship between higher income inequality and greater odds for online gambling may be mediated by depressive and anxiety symptoms, psychosocial well-being, and school connectedness. Evidence points to further health consequences, such as online gambling participation, stemming from exposure to income inequality.

Perceived School Belonging Among Youth with Chronic Physical Illness.

In a sample of youth aged 10-16 years with chronic physical illness, this study examined psychometric properties of a modified Psychological Sense of School Membership (m-PSSM) scale; described longitudinal trends in perceptions over 24 months; and, identified factors associated with school belonging. Youth were recruited from a pediatric hospital in Canada. A total of 105 youth attended school in the past year and provided self-reports. The four-item m-PSSM had a unidimensional structure which was measurement invariant between youth in elementary (10-13 years) versus secondary school (14-16 years). Internal consistency was (ω > .80). There was no evidence that m-PSSM scores changed significantly over time (η2 = 0.05). Predictors of lower perceived school belonging were being in secondary school, having psychopathology, reporting lower quality of life in the domains of social support and school environment, experiencing peer victimization, and living in a community with higher residential instability and lower material deprivation.

The impact of 12 modifiable lifestyle behaviours on depressive and anxiety symptoms in middle adolescence: prospective analyses of the Canadian longitudinal COMPASS study.

BACKGROUND: Unhealthy lifestyle behaviours are becoming increasingly common and might contribute to the growing burden of mental disorders in adolescence. We examined the associations between a comprehensive set of lifestyle behaviours and depression and anxiety in middle adolescents. METHODS: School-based survey responses were collected from 24,274 Canadian high school students at baseline and 1-year follow-up (average age 14.8 and 15.8 years, respectively). Using linear mixed-effects models, we examined prospective associations of adherence to recommendations for vegetables and fruit, grains, milk and alternatives, meat and alternatives, sugar-sweetened beverages [SSB], physical activity, screen time, sleep, and no use of tobacco, e-cigarettes, cannabis, and binge drinking at baseline with the depressive and anxiety symptoms (measured by CESD-R-10 and GAD-7 scales, respectively) at follow-up. RESULTS: Adherence to recommendations was low overall, particularly for vegetables and fruit (3.9%), grains (4.5%), and screen time (4.9%). Students adhering to individual recommendations, particularly for meat and alternatives, SSB, screen time, sleep, and no cannabis use, at baseline had lower CESD-R-10 and GAD-7 scores at follow-up. Adhering to every additional recommendation was associated with lower CESD-R-10 (ß=-0.15, 95% CI -0.18, -0.11) and GAD-7 scores (ß=-0.10, 95% CI -0.14, -0.07) at follow-up. Assuming cumulative impact, this might translate into 7.2- and 4.8-point lower CESD-R-10 and GAD-7 scores, respectively, among students adhering to 12 vs. 0 recommendations over four years of high school. CONCLUSIONS: The results highlight the preventive potential of population-based approaches promoting healthy lifestyle behaviours, particularly those with the lowest prevalence, as a strategy to improve mental health in adolescence.

The intersection of internalizing symptoms and alcohol use during the COVID-19 pandemic: A prospective cohort study.

Given the well-established relationship between alcohol and internalizing symptoms, potential increases in depression and anxiety during the COVID-19 pandemic may lead to increases in alcohol consumption and binge drinking. This study examines this association from before to during two phases of the pandemic in a cohort of Canadian youth. We used linked data from a sub-sample of 1901 secondary school students who participated in three consecutive school years of the Cannabis use, Obesity, Mental health, Physical activity, Alcohol use, Smoking, and Sedentary behaviour (COMPASS) study between 2018/19 and 2020/21. Separate multilevel logistic regression models examined the association between depression and anxiety symptoms with odds of escalation and reduction (vs. maintenance) and initiation (vs. abstinence) of alcohol consumption. Results show that depression and anxiety symptoms significantly increased over the three years, and these changes were moderated by changes in alcohol consumption and binge drinking. Students with increased depression symptoms were less likely to reduce their alcohol consumption in the early pandemic (Adjust odds ratio [AOR] 0.94, 95% CI:0.90-0.98), more likely to initiate alcohol consumption in the ongoing pandemic period (AOR 1.03, 95% CI: 1.01-1.05), and more likely to initiate binge drinking in both periods. The depression-alcohol use association was stronger among females than males. This study demonstrates a modest association between internalizing symptoms and alcohol use, particularly for depression symptoms and in females. The identified depression-alcohol use association suggests that preventing or treating depression might be beneficial for adolescent alcohol use and vice versa.

Physical activity and recreational screen time change among adolescents in Canada: Examining the impact of COVID-19 in worsening inequity.

The purpose of this study was to assess if sub-populations of adolescents in Canada (i.e., race/ethnicity, sex/gender, and socioeconomic status [SES]) experienced a larger change in physical activity and screen time between the 2019-2020 (pre-pandemic) and the 2020-2021 (mid-pandemic) school years. Longitudinally linked data from pre-pandemic and mid-pandemic school years of a prospective cohort study of secondary school students in Canada (n = 8209) were used for these analyses. Multivariable regression modelling tested the main effects of race/ethnicity, sex/gender, and SES on changes in moderate-to-vigorous physical activity (MVPA) and screen time duration as well as adherence to Canada's 24-h Movement Guidelines. Overall between groups difference were assessed using type II analysis of deviance tests. Interactions between variables of interest were subsequently tested with a series of regression models compared to the main effects model using likelihood-ratio test. Post-hoc comparisons found Male participants' MVPA time decreased less compared to their female counterparts (M [95% CI] = -16.3 [-13.5, -19.2] min/day), but also reported greater increases in screen time compared to females (23.7 [14.7, 32.8] min/day) during the same period. MVPA in White participants decreased less than Asian participants (-10.7 [-19.5, -1.9] min/day) with a similar non-significant pattern observed in Black and Latin participants. Adolescents in higher SES categories fared better on adherence to MVPA (highest vs. lowest OR = 1.41 [0.97, 2.06]) and screen time recommendations(highest vs. lowest AOR = 3.13 [0.91, 11.11]). Results support the hypothesis that existing inequitable sociodemographic differences in MVPA participation and screen time have worsened throughout the pandemic.

Youth Vaping During the Early Stages of the COVID-19 Pandemic Period: Adjusted Annual Changes in Vaping Between the Pre-COVID and Initial COVID-Lockdown Waves of the COMPASS Study.

BACKGROUND: Adolescence is a critical period for vaping onset. The purpose of this article was to examine the effect of the early stages of the COVID-19 pandemic period on youth vaping. METHODS: We used 3-year linked data from the COMPASS study, including 7585 Canadian (Quebec, Ontario) adolescents from which 1949 completed all three survey waves (pre-COVID-19 [2018, 2019] and online [2020] during the early pandemic period [May-July 2020]) and provided vaping data. Structural equation modeling (SEM) and difference-in-difference (DD) models were used to estimate pre-COVID-19 to initial COVID-19 pandemic period change (2019-2020) in vaping (monthly, weekly, daily) compared with 2018-2019 change to adjust for age-related effects. Models were adjusted for age of entry into the cohort and sociodemographic characteristics. RESULTS: In the SEM and DD models, the proportion of youth who were monthly and weekly vaping increased from 2018 to 2019 but decreased from 2019 to 2020; daily vaping increased across all waves. However, for all vaping outcomes modeled, the expected increases from the pre-COVID-19 wave (2019) to the initial COVID-19 period wave (2020) were lesser relative to the changes seen across the 2018 to 2019 waves. CONCLUSION: The early stages of the COVID-19 pandemic period appear to be associated with a reduction in the proportion of youth who were monthly and weekly vapers in our adjusted longitudinal models. While daily vaping increased over this same period of time, the magnitude of the increase in our adjusted longitudinal models appears attenuated by the early stages of the pandemic. IMPLICATIONS: This large prospective study of youth that included pre-pandemic data is unique in that we were able to identify that the early stages of the COVID-19 pandemic period was associated with a reduction in the proportion of youth who were monthly and weekly vapers in our adjusted longitudinal models. Conversely, the proportion of youth who were daily vaping increased over this same period of time, but the magnitude of the increase appears smaller than expected during the early stages of the pandemic in our adjusted longitudinal models. This study provides novel robust evidence that the patterns of vaping most aligned with onset and progression (i.e., monthly and weekly use) appear attenuated during the initial pandemic period.

Stronger together: Coping behaviours and mental health changes of Canadian adolescents in early phases of the COVID-19 pandemic.

BACKGROUND: The impact of the COVID-19 pandemic and consequent public health restrictions on the mental health of adolescents is of global concern. The purpose of this study was to examine how Canadian adolescents coped during the early pandemic and whether different coping methods were associated with changes in mental health from before the pandemic to the early lockdown response. METHODS: Using two-year linked survey data (2018-2020) from a prospective cohort of secondary school students (n = 3,577), linear regression models were used to examine whether changes in mental health (anxiety [Generalized Anxiety Disorder-7 scale], depression [Center for Epidemiologic Studies Depression 10-item scale Revised], emotion regulation [Difficulties in Emotion Regulation Scale], psychosocial well-being [Flourishing scale]) were related to each coping behaviour. RESULTS: The most common reported coping behaviours included staying connected with friends online (78.8%), playing video games, watching TV/movies, and/or surfing the internet/social media (76.2%), studying or working on schoolwork (71.0%), and getting exercise (65.2%). The use of positive coping mechanisms during the early pandemic period (e.g., keeping a regular schedule, time with family, time with friends online) was associated with less adverse mental health changes from before to during the early lockdown; whereas, negative coping mechanisms (e.g., spending time alone, eating junk food) were consistently associated with more adverse mental health changes. CONCLUSION: This study demonstrates the importance of social support and connections with both friends and family, as well as keeping and maintaining a routine, over the pandemic. Interventions supporting positive relationships and engagement in these coping behaviours may be protective for adolescent mental health during disruptive events.

Learning from missing data: examining nonreporting patterns of height, weight, and BMI among Canadian youth.

BACKGROUND: Youth body mass index (BMI), derived from self-reported height and weight, is commonly prone to nonreporting. A considerable proportion of overweight and obesity (OWOB) research relies on such self-report data, however little literature to date has examined this nonreporting and the potential impact on research conclusions. The objective of this study was to examine the characteristics and predictors of missing data in youth BMI, height, and weight. METHODS: Using a sample of 74,501 Canadian secondary school students who participated in the COMPASS study in 2018/19, sex-stratified generalized linear mixed models were run to examine predictors of missing data while controlling for school-level clustering. RESULTS: In this sample, 31% of BMI data were missing. A variety of diet, exercise, mental health, and substance use variables were associated with BMI, height, and weight missingness. Perceptions of being overweight (females: 95% CI (1.42,1.62), males: 95% CI (1.71,2.00)) as well as intentions to lose weight (females: 95% CI (1.17,1.33), males: 95% CI (1.13,1.32)) were positively associated with BMI missingness. CONCLUSIONS: Findings from this study suggest that nonreporting in youth height and weight is likely somewhat related to the values themselves, and hint that social desirability may play a substantial role in nonreporting. The predictors of missingness identified in this study can be used to inform future studies on the potential bias stemming from missing data and identify auxiliary variables that may be used for multiple imputation approaches.

A scoping review of school-level risk and protective factors of youth cannabis use: An application of the socio-ecological model.

Risk and protective factors for cannabis use exist at various levels of influence, and the school environment can play a key role in preventing cannabis use and initiation as most youth. By using the socio-ecological model to hierarchically characterize school-specific risk and protective factors, a wholistic approach to school-based cannabis use prevention can be demonstrated. This study uses scoping review methodology to describe current research on school-level risk and protective factors of youth cannabis use. The socio-ecological model was used as a guiding framework to characterize the literature. PubMed, Embase, and Scopus were used to retrieve original research articles published between 2010 and 2020 that examined cannabis use as a main outcome of interest. Articles that examined school-related risk and protective factors within participants who were 18 years old or younger were included. Articles that met the pre-established criteria were extracted and categorised by theme based on levels of the socio-ecological framework. Four levels of risk and protective factors related to the school environment were identified (individual, interpersonal, community, and societal). A majority of school-based research examined individual and societal factors that influenced youth cannabis use. Our findings suggest most available research has focused on individual and societal school-level factors of cannabis use. A number of consistent themes were identified, however, findings were mixed and demonstrate the need for a more critical examination of research in order to understand which risk and protective factors are most influential among youth.