Exploring the association between income inequality and sleep in Canadian adolescents: A path analysis approach.

OBJECTIVES: An estimated 30% of Canadian adolescents do not get the recommended 8-10hours of sleep. No prior study has examined the role of income inequality, the gap between rich and poor within a society, in adolescent sleep. The aim of this study is to examine the association between income inequality and sleep duration among Canadian adolescents, how this association differs by gender, and whether depressive symptoms, anxiety, and social cohesion mediate this relationship. METHODS: Multilevel path models were conducted using cross-sectional survey data from 74,501 adolescents who participated in the Cannabis, Obesity, Mental health, Physical activity, Alcohol use, Smoking, and Sedentary behavior (COMPASS) study in 2018-2019. Income inequality was measured at the census division level and sleep duration, gender, depressive symptoms, anxiety, and social cohesion were measured at the individual level. RESULTS: A 1% increase in income inequality was associated with a 3.67-minute decrease in sleep duration (95% CI=-5.64 to -1.70). The cross-level interactions between income inequality and gender were significant, suggesting that income inequality has more adverse associations with sleep among females than males. Both depressive symptoms and anxiety were significant mediators, wherein greater income inequality was associated with higher levels of depressive symptoms and anxiety, which were in turn, associated with a shorter sleep duration. CONCLUSION: Interventions that reduce income inequality may prevent depressive symptoms and anxiety and improve sleep in adolescents. Reducing societal income gaps may improve adolescent sleep especially in those attending school in high income inequality areas, females, and those experiencing depressive symptoms and anxiety.

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.

Income inequality and mental health in adolescents during COVID-19, results from COMPASS 2018-2021.

INTRODUCTION: Understanding the inequitable impacts of the ongoing COVID-19 pandemic on youth mental health are leading priorities. Existing research has linked income inequality in schools to adolescent depression, however, it is unclear if the onset of the pandemic exacerbated the effects of income inequality on adolescent mental health. The current study aimed to quantify the association between income inequality and adolescent mental health during COVID-19. MATERIAL AND METHODS: Longitudinal data were taken from three waves (2018/19 to 2020/21) of the Cannabis, Obesity, Mental health, Physical activity, Alcohol, Smoking, and Sedentary behaviour (COMPASS) school-based study. Latent Growth Curve modelling was used to assess the association between Census District (CD)-level income inequality and depressive symptoms before and after the onset of COVID-19. RESULTS: The study sample included 29,722 students across 43 Census divisions in British Columbia, Alberta, Ontario, and Quebec. The average age of the sample at baseline was 14.9 years [standard deviation (SD) = 1.5] and ranged between 12 and 19 years of age. Most of the sample self-reported as white (76.3%) and female (54.4%). Students who completed the COMPASS survey after the onset of COVID reported 0.20-unit higher depressive scores (95% CI = 0.16, 0.24) compared to pre-COVID. The adjusted analyses indicated that the association between income inequality on anxiety scores was strengthened following the onset of COVID-19 (ß = 0.02, 95% CI = 0.0004, 0.03), indicating that income inequality was associated with a greater increase in anxiety scores during COVID-19. DISCUSSION: The adjusted results indicate that the association between income inequality and adolescent anxiety persisted and was heightened at the onset of COVID-19. Future studies should use quasi-experimental methods to strengthen this finding. The current study can inform policy and program discussions regarding the effects of the COVID-19 pandemic and pandemic recovery for young Canadians and relevant social policies for improving adolescent mental health.

Exploring the longitudinal associations between census division income inequality and BMI trajectories among Canadian adolescent: Is gender an effect modifier?

Background: Income inequality is a structural determinant of health linked to increased risk of overweight and obesity, although its links to the health of adolescent populations are not well understood. This study investigated the longitudinal associations between census-division-level (CD) income inequality and BMI trajectories among Canadian adolescents, and determine if these associations vary by gender. Methods: Study data are from the Cannabis use, Obesity, Mental health, Physical Activity, Alcohol use, Smoking, and Sedentary behaviour (COMPASS) cohort of adolescents attending secondary schools in Canada. Our sample included 14,675 adolescents who were followed up across three waves of the COMPASS study (2016-2017, 2017-2018, and 2018-2019) and linked to 30 CDs. Measures of income inequality and other area-level covariates were derived and linked to COMPASS participants using data from the 2016 Canadian Census. We utilized multilevel mixed-effects linear regression modelling to quantify the associations between income inequality and BMI and test for effect modification by gender. Sensitivity analyses were run excluding those with BMI scores in the range considered overweight or obesity at baseline. Results: Higher CD income inequality was significantly associated with higher z-transformed BMI scores (ß = 0.11, 95% CI = 0.034 to 0.19). The interaction term between income inequality and time was not statistically significant, indicating that this association remained constant over time. Once stratified by gender, the association between inequality and BMI became stronger for males (ß = 0.14, 95% CI = 0.060 to 0.022) and attenuated for females (ß = 0.063, 95% CI = -0.047 to 0.17). Conclusion: Attending schools in CDs with higher income inequality was associated with higher BMI scores among male but not female adolescents. Further work is needed to investigate this discrepancy and identify the structural mechanisms that mediate the relationship between inequality and adolescent health.

Inequality's on Tap: A Longitudinal Study of Area-Level Income Inequality and Alcohol Consumption Among Canadian Adolescents.

PURPOSE: To determine if income inequality at the census division level is associated with alcohol consumption and abuse among junior high and high school students. METHODS: Data on adolescents are from the Cannabis use, Obesity, Mental health, Physical activity, Alcohol use, Smoking, and Sedentary behavior (COMPASS) study. Participant data (n = 19,759) were collected during three survey waves (2016-2017, 2017-2018, and 2018-2019) and linked to 30 census divisions within four Canadian provinces. Data on income inequality and other area-level factors were derived from the 2016 Canadian census. Multilevel logistic regression modelling was used to quantify the associations between income inequality, monthly alcohol consumption, and binge drinking. RESULTS: After adjusting for covariates, students living in census divisions within the second and third quintiles of income inequality experienced an average 80% (OR = 1.80, 95% CI = 1.08-3.02) and 92% (OR = 1.92, 95% CI = 1.05-3.51) increased odds of engaging in monthly binge drinking, respectively, compared to those living in the first quintile. Similarly, adolescents living in census divisions within the second inequality quintile experienced an average 169% (OR = 2.69, 95% CI = 1.45, 4.99) increased odds of engaging in weekly binge drinking, compared to those living in the first quintile. There was no significant association between higher income inequality and current monthly alcohol consumption. DISCUSSION: Moderate area-level income inequality within census divisions was adversely associated with alcohol consumption among adolescents. Future work should investigate the potential mechanisms that mediate this relationship.

The association between income inequality and adolescent body mass index: findings from the COMPASS study (2016-2019).

OBJECTIVES: Income inequality has been linked to high and unhealthy body mass index (BMI), though there is a dearth of evidence in adolescents. Therefore, this study examines the association between income inequality and BMI in a large sample of Canadian adolescents. METHODS: A pooled cross-sectional design was used. Participants were adolescents (n = 101,901) from 157 Canadian secondary schools participating in the 2016-2017, 2017-2018, or 2018-2019 waves of the Cannabis, Obesity, Mental health, Physical activity, Alcohol, Smoking, and Sedentary behaviour (COMPASS) study. BMI was calculated from self-reported height and weight and converted to World Health Organization (WHO) z-BMI scores. Gini coefficients were calculated at the census division level (n = 49) using data from the 2016 Canadian Census. Multilevel modelling was performed to account for the clustering of students nested within schools, which were nested within census divisions. Interactions were included to determine whether associations were heterogeneous for males and females. RESULTS: Income inequality demonstrated a non-linear association with WHO z-BMI score (z-Gini: ß = 0.05, 95%CI: 0.02, 0.08; z-Gini2: ß = -0.02, 95% CI: -0.04, -0.01) among adolescents after adjusting for student-, school-, and census division-level covariates. This association was more pronounced among females. CONCLUSION: The association between income inequality and BMI, being overweight, or having obesity appears to be non-linear. Public health units and schools may benefit from incorporating upstream factors such as income inequality into their interventions attempting to promote healthy weights.

RéSUMé: OBJECTIFS: L'inégalité des revenus a été liée à un indice de masse corporelle (IMC) élevé et malsain, bien qu'il y ait un manque de preuves chez les adolescents. Par conséquent, la présente étude examine l'association entre l'inégalité des revenus et l'IMC dans un vaste échantillon d'adolescents canadiens. MéTHODES: Un devis comprenant des études transversales groupées a été utilisé. Les participants étaient des adolescents (n = 101 901) de 157 écoles secondaires canadiennes participant aux vagues 2016-2017, 2017-2018 ou 2018-2019 de l'étude COMPASS (Cannabis, Obésité, Santé mentale, Activité physique, Alcool, Tabagisme et Comportement sédentaire). L'IMC a été calculé à partir de la taille et du poids auto-déclarés et convertis en scores z selon l'Organisation mondiale de la santé (OMS). Les coefficients de Gini ont été calculés à l'échelle du secteur de recensement (n = 49) en utilisant les données du Recensement canadien de 2016. Des modèles multiniveaux ont été effectués pour tenir compte du regroupement des élèves dans les écoles, qui elles-mêmes étaient incluses dans les secteurs de recensement. Des variables d'interactions ont été incluses dans les modèles afin de permettre une comparaison des paramètres estimés entre les hommes et les femmes. RéSULTATS: L'inégalité des revenus a démontré une association non linéaire avec le score de l'IMC z de l'OMS (z-Gini : ß = 0,05, IC à 95 % : 0,02, 0,08; z-Gini2 : ß = -0,02, IC à 95 % : -0,04, -0,01) chez les adolescents après ajustement pour tenir compte des covariables au niveau des élèves, de l'école et des divisions de recensement. Cette association était plus prononcée chez les femmes. CONCLUSION: L'association entre l'inégalité des revenus et l'IMC, l'embonpoint ou l'obésité semble être non linéaire. Les bureaux de santé publique et les écoles pourraient tirer profit de l'intégration de facteurs en amont comme l'inégalité des revenus dans leurs interventions visant à promouvoir le poids santé.

A Longitudinal Study of Income Inequality and Mental Health Among Canadian Secondary School Students: Results From the Cannabis, Obesity, Mental Health, Physical Activity, Alcohol, Smoking, and Sedentary Behavior Study (2016-2019).

PURPOSE: Depression and anxiety among adolescents are major public health concerns. Findings indicate that income inequality was associated with increased risk for depression and anxiety among adolescents; however, this has not been tested longitudinally. We aim to quantify the longitudinal association between income inequality and depression and anxiety among Canadian adolescents. METHODS: We used longitudinal data on 21,141 students from three waves (2016/17-2018/19) of the Cannabis, Obesity, Mental health, Physical activity, Alcohol, Smoking, and Sedentary behavior (COMPASS) school-based study. Multilevel modeling was used to assess the association between census division (CD)-level income inequality and depressive and anxiety symptoms and odds for depression and anxiety over time. RESULTS: Across CDs, the mean Gini coefficient was 0.37 (range: 0.30, 0.46). Attending schools in CDs with higher levels of income inequality was associated with higher depressive scores (ß = 0.08; 95% confidence interval [CI] = 0.02, 0.14) and an increased odds for depression (odds ratio = 1.55, 95% CI = 1.06, 2.28) over time. Income inequality was not significantly associated with anxiety symptoms or experiencing anxiety over time. Additional analyses showed that income inequality was associated with higher depressive scores among females (ß = 0.10; 95% CI = 0.01, 0.18) and males (ß = 0.08, 95% CI = 0.01, 0.15) and for anxiety scores among females (ß = 0.13, 95% CI = 0.04, 0.22), but not among males (ß = -0.01, 95% CI = -0.09, 0.06). DISCUSSION: Findings from this study indicated that income inequality is associated with depression over time among adolescents. This study highlights key points of intervention for the prevention of mental illness in adolescents.

Income inequality and daily use of cannabis, cigarettes, and e-cigarettes among Canadian secondary school students: Results from COMPASS 2018-19.

INTRODUCTION: Cannabis, cigarette, and e-cigarette use among Canadian adolescents is a major public health concern. Income inequality has been associated with adverse mental health among youth and may contribute to the risk of frequent cannabis, cigarette, and e-cigarette use. We tested the association between income inequality and the risk of daily cannabis, cigarette, and e-cigarette use among Canadian secondary school students. METHODS: We used individual-level survey data from Year 6 (2018/19) of Cannabis, Obesity, Mental health, Physical activity, Alcohol use, Smoking, and Sedentary Behavior (COMPASS) and area-level data from the 2016 Canadian Census. Three-level logistic models were used to assess the relationship between income inequality and adolescent daily and current cannabis use, cigarette smoking, and e-cigarette use. RESULTS: The analytic sample included 74,501 students aged 12-19. Students were most likely to report being male (50.4%), white (69.1%), and having weekly spending money over $100 (23.5%). We found that a standard deviation unit increase in Gini coefficient was significantly associated with increased likelihood of daily cannabis use (OR=1.25, 95% CI = 1.01-1.54) when adjusting for relevant covariates. We found no significant relationship between income inequality and daily smoking. While Gini was not significantly associated with daily e-cigarette use, we observed a significant interaction between Gini and gender (OR=0.87, 95% CI= 0.80-0.94), indicating that increased income inequality was associated with higher risk of reporting daily e-cigarette use among females only. DISCUSSION: An association between income inequality and the likelihood of reporting daily cannabis use across all students and daily e-cigarette use in females were observed. Schools in higher income inequality areas may benefit from targeted prevention and harm reduction programs. Results emphasize the need for upstream discussion on policies that can mitigate the potential effects income inequality.

Developing a Socioeconomic Status Index for Chronic Disease Prevention Research in Canada.

Capturing socioeconomic inequalities in relation to chronic disease is challenging since socioeconomic status (SES) encompasses many aspects. We constructed a comprehensive individual-level SES index based on a broad set of social and demographic indicators (gender, education, income adequacy, occupational prestige, employment status) and examined its relationship with smoking, a leading chronic disease risk factor. Analyses were based on baseline data from 17,371 participants of Alberta's Tomorrow Project (ATP), a prospective cohort of adults aged 35−69 years with no prior personal history of cancer. To construct the SES index, we used principal component analysis (PCA) and to illustrate its utility, we examined the association with smoking intensity and smoking history using multiple regression models, adjusted for age and gender. Two components were retained from PCA, which explained 61% of the variation. The SES index was best aligned with educational attainment and occupational prestige, and to a lesser extent, with income adequacy. In the multiple regression analysis, the SES index was negatively associated with smoking intensity (p < 0.001). Study findings highlight the potential of using individual-level SES indices constructed from a broad set of social and demographic indicators in epidemiological research.

Income inequality and depression among Canadian secondary students: Are psychosocial well-being and social cohesion mediating factors?

BACKGROUND: Nearly one-third of secondary school students report experiencing depressive symptoms in the past year. Existing research suggests that increasing rates of depression are due in part to increasing income inequality. The aim of this study is to identify mechanisms by which income inequality contributes to depression among Canadian secondary school students. METHODS: We used data from a large sample of Canadian secondary school students that participated in the 2017/18 wave of the Cannabis, Obesity, Mental health, Physical activity, Alcohol, Smoking, and Sedentary behaviour (COMPASS) study. The sample included 61,642 students across 43 Census divisions (CDs) in Quebec, Ontario, Alberta, and British Columbia. We used multilevel path analysis to determine if the relationship between CD-level income inequality and depression was mediated by student's psychosocial well-being and/or social cohesion. RESULTS: Attending schools in CDs with higher income inequality was related to higher depression scores among Canadian secondary students [unstandardized ß (ß) = 5.36; 95% CI = 0.74, 9.99] and lower psychosocial well-being (ß = -14.83, 95% CI = -25.05, -4.60). Income inequality was not significantly associated with social cohesion, although social cohesion was associated with depression scores among students (ß = -0.31; 95% CI = -0.34, -0.28). DISCUSSION: Findings from this study indicate that income inequality is associated with adolescent depression and that this relationship is mediated by psychosocial well-being. This study is the first of its kind in Canada to assess the mechanisms by which income inequality contributes to adolescent depression. These findings are applicable to school-level programs addressing mental health.

Income Inequality and Bullying Victimization and Perpetration: Evidence From Adolescents in the COMPASS Study.

Previous research indicates that the disproportionate distribution of income within society is associated with aggression and violence. Although research has been conducted identifying the relationship between income inequality and bullying victimization and perpetration, little is known about possible mediators. We investigated the association between income inequality and bullying perpetration and victimization among adolescents participating in the Cannabis, Obesity, Mental health, Physical activity, Alcohol use, Smoking, and Sedentary behavior (COMPASS) study. We identified whether school connectedness and psychosocial well-being mediated the relationship between income inequality and bullying behavior. This study used pooled cross-sectional data from 147,748 adolescents aged 13 to 18 from three waves (2015-2016, 2016-2017, 2017-2018) of the COMPASS study from 157 secondary schools in British Columbia, Alberta, Ontario, and Quebec (Canada). The Gini coefficient was calculated based on the school Census Divisions (CD) using the Canada 2016 Census and linked with student data. We used multilevel modeling to investigate the relationship between income inequality and self-reported bullying victimization and perpetration, while controlling for individual-, school-, and CD-level characteristics. A standard deviation increase in Gini coefficient was associated with increased odds for bullying victimization and perpetration. Findings were observed among girls; however, inequality was only associated with perpetration among boys. We identified social cohesion and psychosocial well-being as potential mediators. To counter the adverse effects of income inequality, school-based interventions designed to increase school connectedness and student psychosocial well-being should be implemented to protect against bullying.

State-level income inequality and the odds for meeting fruit and vegetable recommendations among US adults.

BACKGROUND: Previous research indicates that income inequality is associated with risk for mortality, self-rated health status, chronic conditions, and health behavior, such as physical activity. However, little is known about the relationship between income inequality and dietary intake, which is a major risk factor for common chronic diseases including heart disease, stroke, diabetes, and certain types of cancers. The objective of this study is to determine the association between US state income inequality and fruit and vegetable consumption among adults. METHODS: Cross-sectional data on 270,612 U.S. adults from the U.S. 2013 Behavioral Risk Factor Surveillance System was used. Fruit and vegetable consumption was assessed from the six-item fruit and vegetable frequency questionnaire, which is part of the Behavioral Risk Factor Surveillance System. Multilevel modeling was used to determine whether US state-level income inequality (measured by the z-transformation of the Gini coefficient) was associated with fruit and vegetable consumption adjusting for individual-level and state-level covariates. RESULTS: In comparison to men, women were more likely to consume fruits and vegetables ≥5 times daily, fruits ≥2 times daily, vegetables ≥3 times of daily, and less likely to consume fruit juice daily. Among both men and women, a standard deviation increase in Gini coefficient was associated with an increase in consuming fruit juice daily (OR = 1.07, 95% CI = 1.03, 1.11). However, among women, a standard deviation increase in Gini coefficient was associated with a decreased likelihood in meeting daily recommended levels of both fruits and vegetables (OR = 0.93; 0.87-0.99), fruits only (OR = 0.95; 95% CI, 0.92-0.99) and vegetables only (OR = 0.92; 95% CI, 0.89-0.96). CONCLUSIONS: This study is one of the first to show the relationship between income inequality and fruit and vegetable consumption among U.S. adults empirically. Women's health is more likely to be detrimentally affected when living in a state with higher income inequality.

Body weight misperception and psychological distress among young South Korean adults: the role of physical activity.

BACKGROUND: Emerging evidence suggests that body weight misperception may be associated with psychological distress among people in developed countries. Participating in physical activity (PA) may negate the association between weight misperception and psychological distress given the well-known benefits of PA on psychological health. This study examined the role of PA in associations between body weight misperception and psychological distress among young South Korean adults. METHODS: Data from individuals aged 20 to 39 years who participated in the Fifth Korean National Health and Nutrition Examination Surveys 2010-2012 (N = 6055) was included in the logistic regressions. RESULTS: The proportions of the respondents under- and over-perceiving their body weight were 66.9% and 0.8% among men and 16.3% and 15.6% among women respectively. A moderating effect of PA participation was observed on the relationship between body weight over-perception and depressed mood (Odds Ratio [OR] = 0.55; 95% Confidence Intervals [95% CI] = 0.34, 0.89). Among individuals who did not meet the recommended vigorous-intensity PA (≥ 20 min/session and ≥ 3 day/week), body weight over-perception was associated with depressed mood (OR = 1.71, 95% CI = 1.19, 2.46) compared to the accurate-perception group. However, no association was observed among those who met the recommended vigorous-intensity PA (OR = 1.52, 95% CI = 0.45, 5.22). Similar patterns were found among physically active versus inactive individuals (recommended walking not met: OR = 2.02, 95% CI = 1.29, 3.15; recommended walking met: OR = 1.28, 95% CI = 0.66, 2.49; muscular strengthening exercises for < 2 day/week: OR = 1.74, 95% CI = 1.21, 2.51; muscular strengthening exercises for ≥ 2 day/week: OR = 1.38, 95% CI = 0.37, 5.14). No relationship existed between body weight over-perception and depressed mood after adjusting for PA. CONCLUSIONS: Participating in regular PA may buffer a potential negative impact of body weight over-perception on depressive mood.

US State-level income inequality and risks of heart attack and coronary risk behaviors: longitudinal findings.

OBJECTIVES: To examine prospectively the association between US state income inequality and incidence of heart attack. METHODS: We used data from the National Epidemiologic Survey on Alcohol and Related Conditions (n = 34,445). Respondents completed interviews at baseline (2001-2002) and follow-up (2004-2005). Weighted multilevel modeling was used to determine if US state-level income inequality (measured by the Gini coefficient) at baseline was a predictor of heart attack during follow-up, controlling for individual-level and state-level covariates. RESULTS: In comparison to residents of US states in the lowest quartile of income inequality, those living in the second [Adjusted Odds Ratio (AOR) = 1.71, 95 % CI 1.16-2.53)], third (AOR = 1.81, 95 % CI 1.28-2.57), and fourth (AOR = 2.04, 95 % CI 1.26-3.29) quartiles were more likely to have a heart attack. Similar findings were obtained when we excluded those who had a heart attack prior to baseline. CONCLUSIONS: This study is one of the first to empirically show the longitudinal relationship between income inequality and coronary heart disease. Living in a state with higher income inequality increases the risk for heart attack among US adults.

Cohort Profile: The Nicotine Dependence in Teens (NDIT) Study.

The Nicotine Dependence in Teens (NDIT) study is a prospective cohort investigation of 1294 students recruited in 1999-2000 from all grade 7 classes in a convenience sample of 10 high schools in Montreal, Canada. Its primary objectives were to study the natural course and determinants of cigarette smoking and nicotine dependence in novice smokers. The main source of data was self-report questionnaires administered in class at school every 3 months from grade 7 to grade 11 (1999-2005), for a total of 20 survey cycles during high school education. Questionnaires were also completed after graduation from high school in 2007-08 and 2011-12 (survey cycles 21 and 22, respectively) when participants were aged 20 and 24 years on average, respectively. In addition to its primary objectives, NDIT has embedded studies on obesity, blood pressure, physical activity, team sports, sedentary behaviour, diet, genetics, alcohol use, use of illicit drugs, second-hand smoke, gambling, sleep and mental health. Results to date are described in 58 publications, 20 manuscripts in preparation, 13 MSc and PhD theses and 111 conference presentations. Access to NDIT data is open to university-appointed or affiliated investigators and to masters, doctoral and postdoctoral students, through their primary supervisor (www.nditstudy.ca).

The relationship between social fragmentation and sleep among adolescents living in Boston, Massachusetts.

BACKGROUND: Sufficient sleep is needed for the healthy development of youth. However, only a small minority of adolescents obtain adequate amounts of sleep. Although individual-level correlates of sleep have been identified, studies investigating the influence of the environment on sleep are warranted. METHODS: By using cross-sectional data collected from 1878 urban adolescents living in 38 neighborhoods participating in the 2008 Boston Youth Survey (BYS), we determined the association between neighborhood social fragmentation and sleep. Social fragmentation of each participant's residential neighborhood was composed using 2010 US Census data. Multilevel regression models were used to determine the association between social fragmentation and meeting the recommended hours of sleep (>8.5 h) and sleep duration while controlling for individual-level sex, race, age and nativity. RESULTS: Moderate (OR = 0.51, 95% CI = 0.27, 0.97) and high (OR = 0.33, 95% CI = 0.18, 0.61) social fragmentation within the residential neighborhood was associated with a decreased likelihood of obtaining adequate sleep. Those in moderate (ß = -23.9, 95% CI = -43.1, -4.8) and high (ß = -22.1, 95% CI = -43.3, -0.9) socially fragmented neighborhoods obtained fewer minutes of sleep per night. CONCLUSIONS: Social fragmentation may be an important determinant of sleep among youth living in urban settings.

Witnessing a violent death and smoking, alcohol consumption, and marijuana use among adolescents.

Witnessing violence has been linked to maladaptive coping behaviors such as smoking, alcohol consumption, and marijuana use. However, more research is required to identify mechanisms in which witnessing violence leads to these behaviors. The objectives of this investigation were to examine the association between witnessing a violent death and smoking, alcohol consumption, and marijuana use among adolescents, to identify whether exhibiting depressive symptoms was a mediator within this relationship, and to determine if those who had adult support in school were less likely to engage in risky health behaviors. Data were collected from a sample of 1,878 urban students, from 18 public high schools participating in the 2008 Boston Youth Survey. In 2012, we used multilevel log-binomial regression models and propensity score matching to estimate the association between witnessing a violent death and smoking, alcohol consumption, and marijuana use. Analyses indicated that girls who witnessed a violent death were more likely to use marijuana (relative risk (RR) = 1.09, 95% confidence interval (CI) = 1.02, 1.17), and tended towards a higher likelihood to smoke (RR = 1.06, 95% CI = 1.00, 1.13) and consume alcohol (RR = 1.07, 95% CI = 0.97, 1.18). Among boys, those who witnessed a violent death were significantly more likely to smoke (RR = 1.20, 95% CI = 1.11, 1.29), consume alcohol (RR = 1.30, 95% CI = 1.17, 1.45) and use marijuana (RR = 1.33, 95% CI = 1.21, 1.46). When exhibiting depressive symptoms was included, estimates were not attenuated. However, among girls who witnessed a violent death, having an adult at school for support was protective against alcohol consumption. When we used propensity score matching, findings were consistent with the main analyses among boys only. This study adds insight into how witnessing violence can lead to adoption of adverse health behaviors.

The importance of Active Transportation to and from school for daily physical activity among children.

OBJECTIVE: To investigate if students who use of Active Transportation (AT) to and from school among urban and rural Canadian children are more likely to meet physical activity recommendations. METHODS: The Raising healthy Eating and Active Living in Alberta (REAL Kids Alberta) study is a population-based health survey among Grade 5 students. In 2009, physical activity levels were measured using time-stamped pedometers (number of steps/hour) among 688 children. Parents reported mode of transportation to and from school (AT/non-AT). Multilevel multiple linear regression analyses with corresponding ß coefficients were conducted to quantify the relationship between mode of transportation to and from school with (1) overall step count, and (2) the likelihood of achieving at least 13,500 steps per day recommended for optimal growth and development. RESULTS: Among urban children, those who used AT to and from school accumulated more steps [ß=1124(95% CI=170,2077)] and although not significant, were more likely to achieve the recommended 13,500 steps/day compared to those not using AT to and from school [OR=1.61(95% CI=0.93,2.81)]. CONCLUSION: Using AT to and from school appears to be beneficial to children by supplementing their physical activity, particularly those living in urban regions. Strategies to promote physical activity are needed, particular for children residing in rural regions and smaller towns.

Does intolerance of smoking at school or in restaurants or corner stores decrease cigarette use initiation in adolescents?

INTRODUCTION: In addition to individual-level characteristics, the social and physical environment may influence the initiation of cigarette smoking in adolescents. The objective of this paper is to describe the association between smoking intolerance in schools, and in restaurants and corner stores located near schools, and initiation of cigarette smoking among adolescents. METHODS: Data on cigarette smoking were collected in self-report questionnaires every 3 months from 1999 to 2005 in a sample of 1,293 Grade 7 students in 10 secondary schools in Montreal, Canada. Baseline never-smokers (n = 868) were retained for analysis. School administrators completed questionnaires on tobacco control policies and activities within schools. Data on access to tobacco products and smoking restrictions in restaurants and corner stores located in school neighborhoods were collected through direct observation. Schools, restaurants, and corner stores were classified as smoking tolerant or intolerant. Time to initiation of cigarette smoking was modeled as a function of smoking intolerance in schools, restaurants, and corner stores in survival analyses (Cox proportional hazards modeling). RESULTS: Students in smoking-intolerant schools were less likely to initiate smoking than students in smoking-tolerant schools (hazard ratio [HR; 95% CI] = 0.83 [0.68, 1.01]). Students attending schools located in neighborhoods with smoking-intolerant restaurants were less likely to initiate smoking (HR [95% CI] = 0.85 [0.68, 1.07]). There was no association between corner store smoking intolerance and initiation. CONCLUSIONS: Smoking intolerance in schools and restaurants may protect against initiation of cigarette smoking and could be useful targets for more intense tobacco control efforts.