[Show abstract][Hide abstract] ABSTRACT: Few studies consider how risk factors within multiple levels of influence operate synergistically to determine childhood obesity. We used recursive partitioning analysis to identify unique combinations of individual, familial, and neighborhood factors that best predict obesity in children, and tested whether these predict 2-year changes in body mass index (BMI).
Data were collected in 2005-2008 and in 2008-2011 for 512 Quebec youth (8-10 years at baseline) with a history of parental obesity (QUALITY study). CDC age- and sex-specific BMI percentiles were computed and children were considered obese if their BMI was ≥95(th) percentile. Individual (physical activity and sugar-sweetened beverage intake), familial (household socioeconomic status and measures of parental obesity including both BMI and waist circumference), and neighborhood (disadvantage, prestige, and presence of parks, convenience stores, and fast food restaurants) factors were examined. Recursive partitioning, a method that generates a classification tree predicting obesity based on combined exposure to a series of variables, was used. Associations between resulting varying risk group membership and BMI percentile at baseline and 2-year follow up were examined using linear regression.
Recursive partitioning yielded 7 subgroups with a prevalence of obesity equal to 8%, 11%, 26%, 28%, 41%, 60%, and 63%, respectively. The 2 highest risk subgroups comprised i) children not meeting physical activity guidelines, with at least one BMI-defined obese parent and 2 abdominally obese parents, living in disadvantaged neighborhoods without parks and, ii) children with these characteristics, except with access to ≥1 park and with access to ≥1 convenience store. Group membership was strongly associated with BMI at baseline, but did not systematically predict change in BMI.
Findings support the notion that obesity is predicted by multiple factors in different settings and provide some indications of potentially obesogenic environments. Alternate group definitions as well as longer duration of follow up should be investigated to predict change in obesity.
Preview · Article · Dec 2015 · International Journal of Behavioral Nutrition and Physical Activity
[Show abstract][Hide abstract] ABSTRACT: Background:
Parks are increasingly being viewed as a resource that may influence youth obesity and physical activity (PA). Assessing park quality can be challenging as few tools assess park characteristics geared towards youth PA. Additionally, no studies have compared reliability estimates of items assessed in different countries, hindering aims towards generalizable park audit items. Finally, new satellite imaging technology is allowing for desktop identification of parks, however it remains unclear how this compares to direct observation park identification. The purpose of this study is 1) to describe the development and reliability of a youth-oriented direct-observation park audit tool tested in Montreal, Canada, and; 2) to compare reliability estimates of items with those drawn from a tool previously tested in Perth, Australia, with those same items tested in Montreal, Canada.
Items were drawn and adapted from two existing tools and 13 new items were newly developed for a total of 92 items. Parks were pre-identified using a GIS software and then verified and audited on-site by observers. A total of 576 parks were evaluated. Cohen's kappa and percent agreement were used to assess the inter- and intra-rater reliability of each item. Inter-rater reliabilities of 17 items drawn from a tool previously tested in Australia were compared.
Eighty-six percent of items had ≥ 75 % agreement and 83 % had kappa coefficients between 0.41 and 1. Among 40 test-retest episodes kappa agreement was relatively high (≥ 0.40) for all but four items. Percent agreement was excellent (≥ 75 % agreement) for all but eight items. Inter-rater reliability estimates of the 17 items tested in Montreal and Perth were of similar magnitude.
The tool is generally reliable and can be used to assess park characteristics that may be associated with youth PA. The items tested in Montreal and Perth are likely generalizable to other urban environments.
[Show abstract][Hide abstract] ABSTRACT: Adolescent physical activity (PA) levels track into adulthood. However it is not known if type of PA participated in during adolescence is associated with PA levels later in life. We aimed to identify natural groupings of types of PA and to assess whether number of years participating in these different groupings during adolescence is related to PA level in early adulthood.
673 adolescents in Montreal, Canada, age 12-13 years at baseline (54 % female), reported participation in 29 physical activities every 3 months over 5 years (1999-2005). They also reported their PA level at age 24 years (2011-12). PA groupings among the 29 physical activities were identified using factor analysis. The association between number of years participating in each grouping during adolescence and PA level at age 24 was estimated using linear regression within a general estimating equation framework.
Three PA groupings were identified: "sports", "fitness and dance", and "running". There was a positive linear relationship between number of years participating in sports and running in adolescence and PA level at age 24 years (β (95 % confidence interval) = 0.09 (0.04-0.15); 0.08 (0.01-0.15), respectively). There was no relationship between fitness and dance in adolescence and PA level at age 24.
The association between PA participation in adolescence and PA levels in young adulthood may be specific to certain PA types and to consistency of participation during adolescence. Results suggest that efforts to establish the habit of participation in sports and running in adolescence may promote higher PA levels in adulthood.
Full-text · Article · Jun 2015 · International Journal of Behavioral Nutrition and Physical Activity
[Show abstract][Hide abstract] ABSTRACT: Objective: To investigate whether children's perceptions of neighborhood safety are associated with their weight status and weight-related behaviors, independently of their parents' perceptions.
Methods: Data were from the baseline wave (collected in 2005-2008) of the Quebec Adipose and Lifestyle Investigation in Youth (QUALITY), an ongoing prospective study of 630 children aged 8-10 years (from Quebec, Canada) at risk of obesity. Weight and height were measured, and WHO age- and sex-specific BMI z-scores were computed. Physical activity was measured by accelerometry, and time spent watching television, playing computer and video games during week and weekend days was self-reported. Structural equation modeling was used to simultaneously estimate the associations between parent and child perceived safety, with children's BMI z-score, physical activity, and screen time.
Results: The results suggest that, when parent perceived safety was at the mean, children who perceived their neighborhood as being safest had nearly an additional 70 daily activity counts-per-minute (representing an approximate 10% increase in overall physical activity level) compared to children who perceived it as being least safe. Among children who perceived a mean level of safety, those whose parents perceived their neighborhood as being safest spent approximately an hour less per day in front of screens compared to those whose parents perceived their neighborhood as being least safe. Parent and child perceptions of safety both indirectly contribute to children's weight status by differentially impacting weight-related behaviors.
Conclusion: Findings indicate that targeting both parent and child perceived neighborhood safety could bolster efforts to promote healthy weight and weight-related behaviors among children.
No preview · Article · May 2015 · International Journal of Obesity
[Show abstract][Hide abstract] ABSTRACT: Parent and child perceived neighborhood safety predicts child health outcomes such as sleep quality, asthma, physical activity, and psychological distress. Although previous studies identify environmental predictors of parent perceived safety, little is known about predictors of child perceived safety. This study aims to identify the social and physical environmental neighborhood features that predict child and parent perceived neighborhood safety and, simultaneously, to assess the association between child and parent perceptions. Data were from the QUebec Adipose and Lifestyle InvesTigation in Youth (QUALITY) cohort, an ongoing study of Caucasian children (aged 8–10 years) with a parental history of obesity, and their biological parents from Québec, Canada. Measures of social and physical neighborhood features were collected using a spatial data infrastructure and in-person audits. Structural equation modeling was used to test direct and indirect associations between neighborhood features, child and parent perceived safety. Results suggest that among children (N = 494), trees and lighting were positively associated with perceived neighborhood safety, whereas a high proportion of visible minorities was associated with poorer perceived safety. Parents’ perceptions of safety were more strongly tied to indicators of disorder and a lack of community involvement, and to traffic. Child perceived safety was partly explained by parent perceived safety, suggesting moderate concordance between perceptions. Although associated with each other, parent and child perceived safety seemed to be determined by distinct environmental features. Though this study focused on determinants of child and parent perceived safety, future research investigating the impact of neighborhood safety on child health should consider both child and parent perspectives.
Full-text · Article · Dec 2014 · Journal of Urban Health
[Show abstract][Hide abstract] ABSTRACT: Although disadvantaged youth are more likely to be victimized at school, victimization only partly explains their decreased feelings of safety at school. We applied a socioecological approach to test the hypotheses that the experience of poverty is associated with decreased feelings of safety at school, and that residential neighborhood features partly mediate the relationship between poverty and feeling less safe at school. This study draws on the Québec Longitudinal Study of Child Development (QLSCD) which began in 1998 with a representative population-based cohort of 2,120 5-month old infants (49.1 % female) and their primary caregiver. The study also includes measures of ego-centred residential neighborhood exposures (based on a 500 m circular buffer zone surrounding the family's residential postal code) derived from a spatial data infrastructure. We used latent growth modeling to estimate youth's family poverty trajectory from age 5 months to 13 years, and structural equation modeling to test our hypotheses. The results suggest that youth experiencing chronic and later-childhood poverty felt less safe at school in part because they lived in neighborhoods that their parents described as being disorderly (e.g., demarked by the presence of garbage, drug use and groups of trouble-makers). These neighborhoods also tended to have less greenery (e.g., trees, parks) and more lone-parent households. Neighborhood features did not help explain the relationship between early-childhood poverty and feeling less safe at school. The findings suggest that targeting residential neighborhood features such as greenery and disorder could improve youth's felt safety at school, particularly for those experiencing chronic and later-childhood poverty.
Full-text · Article · Nov 2014 · Journal of Youth and Adolescence
[Show abstract][Hide abstract] ABSTRACT: Background
Two thirds of the U.S. population is overweight or obese, but those living in poverty are disproportionately affected. Although 30%−50% of Americans report currently trying to lose weight, some strategies may be counterproductive. Little is known about how income may be associated with weight-loss strategies.
This study aims to determine the association between income and weight-loss strategies in the general U.S. population.
Cross-sectional data from the National Health and Nutrition Examination Survey were collected in 1999−2010 and analyzed in 2012. Annual household income was categorized as <$20,000, $20,000−$44,999, $45,000−$74,999, ≥$75,000 (ref). Analyses were stratified by age (youth: aged 8−19 years, n=3,184; adults: aged ≥20 years, n=5,643) and included sampling weights. Multivariable logistic regression assessed the likelihood of using specific strategies and utilizing strategies consistent with recommendations (such as exercising or reducing fat or sweets) and inconsistent (such as skipping meals or fasting) and adjusted for gender, age, ethnicity, and whether the person was overweight or obese. Analyses among adults were also adjusted for marital status and education.
Compared to the ref, both youth and adults with household income <$20,000/year were 33% (95% CI=0.5, 0.9) and 50% (95% CI=0.4, 0.6) less likely to use strategies consistent with recommendations to lose weight, respectively. Youth from households with income <$20,000/year were 2.5 times (95% CI=1.8, 3.5) more likely to use inconsistent strategies, but this association was not observed among adults.
Stronger efforts to emphasize weight-loss strategies consistent with recommendations and the distinction between consistent and inconsistent strategies are needed, especially among lower socioeconomic groups.
No preview · Article · Jun 2014 · American Journal of Preventive Medicine
[Show abstract][Hide abstract] ABSTRACT: Purpose:
Identification of factors that relate to physical activity behavior in children at higher risk for weight problems--namely, children with obese parents--is key to informing the development of effective interventions to promote physical activity and reduce obesity. The purpose of our study was to examine children's perceptions of parental social support for physical activity and the associations between these perceptions and health-enhancing physical activity behavior. Our specific objectives were to: (a) compare perceptions of parental support in children across gender and weight status; (b) compare perceptions of support across source (mother, father) and type (tangible, intangible) in normal-weight and overweight girls and boys; and (c) examine the associations between perceptions of parental support and moderate-to-vigorous physical activity (MVPA) behavior.
We used data collected from the Quebec Adiposity and Lifestyle Investigation in Youth, an investigation of Caucasian children with at least 1 obese biological parent. We included in the analyses children (n = 560, M(age) = 9.6 years, 55% boys, 41% overweight/obese) with data on parental support assessed using a self-report questionnaire and data on MVPA assessed using accelerometers.
Multivariate analyses of variance indicated that perceptions of support differed by children's gender and weight status. Paired-samples t tests showed that children reported more intangible than tangible support. Regression analyses demonstrated that perceptions of paternal tangible support were positively related to MVPA in normal-weight girls, but only a small amount of variance was explained.
Children's gender and weight status need to be considered when studying parental support for physical activity. Further, type and source of support should be differentiated in future research.
No preview · Article · Jun 2014 · Research quarterly for exercise and sport
[Show abstract][Hide abstract] ABSTRACT: This study examined (1) the factor structure of a depressive symptoms scale (DSS), (2) the sex and longitudinal invariance of the DSS, and (3) the predictive validity of the DSS scale during adolescence in terms of predicting depression and anxiety symptoms in early adulthood.
Data were drawn from the Nicotine Dependence in Teens (NDIT) study, an ongoing prospective cohort study of 1,293 adolescents.
The analytical sample included 527 participants who provided complete data or had minimal missing data over follow-up. Confirmatory factor analysis revealed that an intercorrelated three-factor model with somatic, depressive, and anxiety factors provided the best fit. Further, this model was invariant across sex and time. Finally, DSS scores at Time 3 correlated significantly with depressive and anxiety symptoms measured at Time 4.
Results suggest that the DSS is multidimensional and that it is a suitable instrument to examine sex differences in somatic, depressive, and anxiety symptoms, as well as changes in these symptoms over time in adolescents. In addition, it could be used to identify individuals at-risk of psychopathology during early adulthood.
[Show abstract][Hide abstract] ABSTRACT: Objectives:
To determine the independent associations of moderate to vigorous physical activity (MVPA), fitness, screen time, and adiposity with insulin secretion in children.
Design and methods:
Caucasian youth (n = 423/630), 8-10 years old, with at least one obese biological parent, were studied (QUALITY cohort). Insulin secretion was measured using HOMA2-%B, area under the curve (AUC) of insulin to glucose over the first 30 minutes (AUC I/G(t30min)) of the OGTT and AUC I/G(t120min) over 2 hours. Fitness was measured by VO₂peak ; percent fat mass (PFM) by DXA; 7-day MVPA by accelerometry; self-reported screen time included television, video game, or computer use. Models were adjusted for age, sex, season, puberty, PFM, and insulin sensitivity [IS] (HOMA2-IS, Matsuda-ISI).
PFM was strongly associated with insulin secretion, even after adjustment for IS: for every 1% increase in PFM, insulin secretion increased from 0.3% to 0.8% across indices. MVPA was negatively associated with HOMA2-%B (P < 0.05), but not with OGTT-derived measures. Fitness was negatively associated with AUC I/G(t120min) (P < 0.05). Screen time showed a trend toward higher HOMA2-%B in girls (P = 0.060).
In children with an obese parent, lower insulin secretion is associated with lower adiposity, higher MVPA, better fitness, and possibly reduced screen time.
[Show abstract][Hide abstract] ABSTRACT: Skateboarding is considered to be a high risk activity. Although many studies have identified risk factors associated with skateboarding injuries, few have provided detailed in-depth knowledge on participants’ psychological dispositions towards risk behaviors. The aim of this study was to identify individual factors associated with risk perception and risk-taking among skateboarders. Telephone interviews were conducted with 158 skateboarders (mean age = 18.1 years) recruited in 11 Montreal skateparks. Age, self-efficacy, previous injuries, fear of being injured, sensation seeking and experience level were all included in two linear regression models that were run for risk perception and risk-taking. Age, experience level, sensation seeking, and risk perception are significant explanatory variables of risk-taking. Results show that sensation seeking was the only significant factor associated with risk perception. These results allow for a better understanding of the behavior of skateboarders, they highlight the importance of impulsive sensation seeking in risk perception as well as risk-taking. This study characterizes skateboarders who take risks and provides additional information on interventions for injury prevention.
[Show abstract][Hide abstract] ABSTRACT: Findings from prospective studies on associations between physical activity and adiposity among youth are inconsistent. Our aim was to describe physical activity trajectories during secondary school and examine the association with change in adiposity in youth.
Physical activity was measured in 20 survey cycles from 1999 to 2005; anthropometrics were measured in survey cycles 1, 12, and 19. Individual growth curves modeling moderate-to-vigorous physical activity (MVPA) and vigorous physical activity (VPA) were estimated. Estimates of initial level and rate of decline in MVPA and VPA bouts per week were included as potential predictors of body fat% and body mass index using age- and sex-specific linear regression.
Complete data were available for 840 and 760 adolescents aged 12-13 years at baseline, followed from survey cycles 1-12 and 12-19, respectively. Among girls, yearly declines of one MVPA and one VPA bout per week during earlier adolescence were associated with increases of 0.19 (95% confidence interval [CI], 0.02-0.36) and 0.47 (95% CI, 0.015-0.92) units of body fat%, respectively. In boys, a yearly decline of one MVPA bout per week was associated with an increase of 0.38 (95% CI, 0.05-0.70) units of body fat% during later adolescence.
Obesity prevention programs should include strategies to prevent declines in physical activity.
Full-text · Article · Sep 2013 · Annals of epidemiology
[Show abstract][Hide abstract] ABSTRACT: Background:
Using a large population-based sample, this study aims to verify whether televiewing at 29 mo, a common early childhood pastime, is prospectively associated with school readiness at 65 mo.
Participants are a prospective longitudinal cohort of 991 girls and 1,006 boys from the Quebec Longitudinal Study of Child Development with parent-reported data on weekly hours of televiewing at 29 mo of age. We conducted a series of ordinary least-squares regressions in which children's scores on direct child assessments of vocabulary, mathematical knowledge, and motor skills, as well as kindergarten teacher reports of socioemotional functioning, were linearly regressed on early televiewing.
Every SD increase (1.2 h) in daily televiewing at 29 mo predicted decreases in receptive vocabulary, number knowledge scores, classroom engagement, and gross motor locomotion scores, as well as increases in the frequency of victimization by classmates.
Increases in total time watching television at 29 mo were associated with subsequent decreases in vocabulary and math skills, classroom engagement (which is largely determined by attention skills), victimization by classmates, and physical prowess at kindergarten. These prospective associations, independent of key potential confounders, suggest the need for better parental awareness and compliance with existing viewing recommendations put forth by the American Academy of Pediatrics (AAP).
Full-text · Article · Jun 2013 · Pediatric Research
[Show abstract][Hide abstract] ABSTRACT: Objective:
To examine associations between characteristics of neighborhood built and social environments and likelihood of obesity among family triads living at the same residential address and to explore whether these associations differ between family members.
Data were from the baseline wave of QUALITY (Quebec Adipose and Lifestyle Investigation in Youth), an ongoing study on the natural history of obesity in 630 Quebec youth aged 8-10 years with a parental history of obesity. Weight and height were measured in children and both biological parents and body mass index was computed. Residential neighborhood environments were characterized using a Geographic Information System and in-person neighborhood audits. Principal components analysis allowed for identification of overarching neighborhood indicators including poverty, prestige, level of urbanicity, traffic, physical disorder and deterioration, and pedestrian friendliness. Multilevel logistic regressions were used to examine associations between neighborhood indicators and obesity within multiple family members residing at the same address while controlling for household-level sociodemographic variables.
A total of 417 families were included in the analysis. Families residing in lower and average prestige neighborhoods were more likely to be obese (odds ratio (OR)=1.69, 95% confidence interval (CI): 1.16, 2.44, and OR=1.51, 95% CI: 1.09, 2.11, respectively) than those residing in higher prestige neighborhoods. Residing in lower traffic neighborhoods was associated with less obesity (OR=0.69, 95% CI: 0.50, 0.95). Other neighborhood indicators may have differential effects across family members. For example, as neighborhood poverty increased, obesity was more likely among children but less likely among fathers and no different for mothers.
Findings indicate that some shared neighborhood exposures are associated with greater risk of obesity for entire families whereas other exposures may heighten obesity risk in some but not all family members. Patterns may reflect differences in the way in which family members use residential neighborhood environments.
No preview · Article · May 2013 · International journal of obesity (2005)
[Show abstract][Hide abstract] ABSTRACT: This study describes developmental trajectories of depressive symptoms in adolescents and examines the association between trajectory group and mental health outcomes in young adulthood.
Depressive symptoms were self-reported every three months from grade seven through grade 11 by 1293 adolescents in the Nicotine Dependence in Teens (NDIT) study and followed in young adulthood (average age 20.4, SD=0.7, n=865). Semi-parametric growth modeling was used to identify sex-specific trajectories of depressive symptoms.
THREE DISTINCT TRAJECTORY GROUPS WERE IDENTIFIED: 50% of boys and 29% of girls exhibited low, decreasing levels of depressive symptoms; 14% of boys and 28% of girls exhibited high and increasing levels; and 36% of boys and 43% of girls exhibited moderate levels with linear increase. Trajectory group was a statistically significant independent predictor of depression, stress, and self-rated mental health in young adulthood in boys and girls. Boys, but not girls, in the high trajectory group had a statistically significant increase in the likelihood of seeking psychiatric care.
Substantial heterogeneity in changes in depressive symptoms over time was found. Because early depressive symptoms predict mental health problems in young adulthood, monitoring adolescents for depressive symptoms may help identify those most at risk and in need of intervention.
Full-text · Article · May 2013 · Journal of the Canadian Academy of Child and Adolescent Psychiatry = Journal de l'Academie canadienne de psychiatrie de l'enfant et de l'adolescent
[Show abstract][Hide abstract] ABSTRACT: Purpose:
Taking advantage of a natural experiment made possible by the placement of health-promoting vending machines (HPVMs), we evaluated the impact of the intervention on consumers' attitudes toward and practices with vending machines in a pediatric hospital.
Vending machines offering healthy snacks, meals, and beverages were developed to replace four vending machines offering the usual high-energy, low-nutrition fare. A pre- and post-intervention evaluation design was used; data were collected through exit surveys and six-week follow-up telephone surveys among potential vending machine users before (n=293) and after (n=226) placement of HPVMs. Chi-2 statistics were used to compare pre- and post-intervention participants' responses.
More than 90% of pre- and post-intervention participants were satisfied with their purchase. Post-intervention participants were more likely to state that nutritional content and appropriateness of portion size were elements that influenced their purchase. Overall, post-intervention participants were more likely than pre-intervention participants to perceive as healthy the options offered by the hospital vending machines. Thirty-three percent of post-intervention participants recalled two or more sources of information integrated in the HPVM concept. No differences were found between pre- and post-intervention participants' readiness to adopt healthy diets.
While the HPVM project had challenges as well as strengths, vending machines offering healthy snacks are feasible in hospital settings.
No preview · Article · Mar 2013 · Canadian Journal of Dietetic Practice and Research