Influence of country of birth and ethnicity on body mass index among Canadian youth: a national survey

Correlations between weight perception and overt risk-taking among Canadian adolescents

OBJECTIVE

Perceptions of body weight represent an important health issue for Canadian adolescents. While associations between weight perception and mental health concerns like eating disorder symptomatology are well established, there is need for more Canadian evidence about how weight perception is associated with overt risk-taking among adolescents, and further how such associations differ by biological sex.

METHODS

We conducted a national analysis of grade 9-10 students participating in the 2017-2018 cycle of the Health Behaviour in School-aged Children (HBSC) study in Canada. This analysis described contemporary patterns of alternate weight perception and then examined the strength and statistical significance of such associations by biological sex, with tobacco, alcohol, and cannabis use, binge drinking, fighting, and illicit drug use as outcomes. Behaviours were considered both individually and in combination. Analyses were descriptive and analytical, with regression models accounting for the nested and clustered nature of the sampling approach.

RESULTS

Responses from 2135 males and 2519 females were available for a complete case series analysis. A total of 26% and 35% of males and females, respectively, perceived themselves as "too fat" while 20% and 9% identified as "too thin". Females perceiving themselves as "too fat" reported higher likelihoods of engaging in individual and scaled indicators of overt risk-taking. Conversely, among males, alternate weight perception was associated with lower levels of such behaviours.

CONCLUSION

As males and females perceive and react to weight perception differently, clinical and health promotion strategies should be developed and uniquely targeted to groups of adolescents in regards to weight perception and risk-taking.

Developmental Trajectory of Body Weight in Youths at Risk for Major Mood Disorders

Importance

Mood disorders are associated with increased body weight, especially in females, but it remains unknown when the weight increase starts.

Objectives

To examine sex-specific weight trajectories associated with familial mood disorder risk and determine the age at which youth at familial risk for mood disorders begin to diverge in weight from controls.

Design, Setting, and Participants

This community-based, single-center, acceleration cohort study of youth at familial risk for mood disorders and controls with yearly follow-ups (mean [SD], 5 [2.1] years) from January 1, 2014, to December 31, 2022, assessed 394 unaffected female and male offspring (aged 3 to 20 years) of parents with or without a mood disorder. Parents with mood (depressive or bipolar) disorders were recruited through adult mental health services. Parents of control participants were matched on age and socioeconomic factors and recruited through acquaintance referrals or schools.

Exposures

The youth in the familial mood risk group had at least 1 parent with a major mood disorder, whereas control youth did not have a parent with a mood disorder.

Main Outcomes and Measures

Body mass indexes (BMIs) were calculated as weight in kilograms divided by height in meters squared from measured weight and height at annual assessments and then converted to age- and sex-adjusted z scores (zBMIs). Repeated-measure regressions examined the association between zBMI and age in youth at familial risk of mood disorders and controls while accounting for sex. Sensitivity analyses accounted for socioeconomic status, prematurity, and birth weight.

Results

Of 394 participants (mean [SD] age, 11.5 [3.6] years; 203 [51.5%] female), youths at familial risk for mood disorders showed overall no difference in body weight (β = 0.12; 95% CI, 0.01-0.24) from controls. A sex-specific difference was detected, with females at familial risk showing a rapid peripubertal increase in body weight, leading to significantly increased zBMIs at 12 years and older compared with controls (β = 0.57; 95% CI, 0.31-0.82) independent of socioeconomic status, prematurity, or birth weight. Males did not differ from controls at any age.

Conclusions and Relevance

In this cohort study, females with a family history of mood disorders were prone to weight gain starting around puberty and predating mood disorder onset. Early interventions aiming to prevent adverse mental and physical outcomes in this vulnerable group need to start in childhood.

Compositional associations of time spent in sleep, screen time, and physical activity with polysubstance use in adolescents

This study of grade 6-10 students used compositional analysis to examine the relationship between the movement behavior composition (time in sleep, screen time, and physical activity) and polysubstance use (frequency of using cigarettes, alternative tobacco products, alcohol, cannabis, and illicit drugs). In grades 6-8 students and grades 9-10 girls: 1) sleep was negatively associated with polysubstance use, 2) screen time was positively associated with polysubstance use, and 3) reallocating physical activity or screen time into sleep was associated with lower polysubstance use. In grades 9-10 boys, reallocating 60 min/day from physical activity into screen time or sleep was associated with greater polysubstance use.

Skeletal growth, body composition, and metabolic risk among North Sudanese immigrant children

OBJECTIVES

Children of immigrants and refugees from developing countries are at risk for poor growth that could contribute to adult chronic disease. This study describes the physical growth, bone growth, body composition, metabolic risks, physical activity, and food security of Sudanese children living in the United States.

DESIGN AND SAMPLE

Cross-sectional descriptive study of 64 Sudanese children age 5-18.

MEASURES

Bone mineral content (BMC), bone density (aBMD), and body composition (fat, lean mass, percent body fat) were measured using DXA. Lipids, insulin, glucose, and hs-CRP were analyzed using standardized laboratory methods. Food security was assessed with the U.S. Household Food Security Survey. Physical activity was measured through self-report questionnaire and pedometers.

RESULTS

About 1/3 of children had low BMC and aBMD. Lean mass was low in 46%, and 32% were obese. Cholesterol, triglycerides, and HOMA-IR were elevated in 23.4%, 32.8%, and 15.6% of children, respectively; only 22% of children were physically active and 40% experienced food insecurity.

CONCLUSION

Sudanese children may have unique risks related to low bone mass low muscle mass, high percent body fat metabolic biomarkers, inactivity, and food insecurity potentially contributing to adult osteoporosis, diabetes, and cardiovascular disease.

Is adherence to the Canadian 24-Hour Movement Behaviour Guidelines for Children and Youth associated with improved indicators of physical, mental, and social health?

The Canadian 24-Hour Movement Guidelines for Children and Youth were released in 2016. These guidelines contained recommendations for moderate to vigorous physical activity, screen time, and sleep duration. The objectives of this study were to determine (i) if achieving the individual recommendations and combinations of the recommendations within the guidelines is associated with indicators of physical, mental, and social health within children and youth; (ii) if meeting the recommendation for a specific movement behaviour is associated with larger differences in physical, mental, and social health indicators compared with meeting the recommendations for the other specific movement behaviours; and (iii) if physical, mental, and social health indicators differ according to different combinations of the guideline recommendations achieved. To address these objectives, we studied a representative sample of over 17 000 Canadians aged 10-17 years. The findings indicated that participants achieving any given recommendation had preferable scores for the health outcomes compared with participants who did not meet the recommendations. There was a dose-response pattern between the number of recommendations achieved and the health outcomes, indicating that the health outcomes improved as more recommendations were achieved. When the number of recommendations achieved was the same, there were no differences in the health outcomes. For instance, health indicators scores were not different in the group who achieved the sleep and screen time recommendations, the group who achieved sleep and moderate to vigorous physical activity recommendations, and the group who achieved screen time and moderate to vigorous physical activity recommendations.

Estimating Whether Replacing Time in Active Outdoor Play and Sedentary Video Games With Active Video Games Influences Youth's Mental Health

PURPOSE

The primary objective was to use isotemporal substitution models to estimate whether replacing time spent in sedentary video games (SVGs) and active outdoor play (AOP) with active video games (AVGs) would be associated with changes in youth's mental health.

METHODS

A representative sample of 20,122 Canadian youth in Grades 6-10 was studied. The exposure variables were average hours/day spent playing AVGs, SVGs, and AOP. The outcomes consisted of a negative and internalizing mental health indicator (emotional problems), a positive and internalizing mental health indicator (life satisfaction), and a positive and externalizing mental health indicator (prosocial behavior). Isotemporal substitution models estimated the extent to which replacing time spent in SVGs and AOP with an equivalent amount of time in AVGs had on the mental health indicators.

RESULTS

Replacing 1 hour/day of SVGs with 1 hour/day of AVGs was associated with a 6% (95% confidence interval: 3%-9%) reduced probability of high emotional problems, a 4% (2%-7%) increased probability of high life satisfaction, and a 13% (9%-16%) increased probability of high prosocial behavior. Replacing 1 hour/day of AOP with 1 hour/day of AVGs was associated with a 7% (3%-11%) increased probability of high emotional problems, a 3% (1%-5%) reduced probability of high life satisfaction, and a 6% (2%-9%) reduced probability of high prosocial behavior.

CONCLUSIONS

Replacing SVGs with AVGs was associated with more preferable mental health indicators. Conversely, replacing AOP with AVGs was associated with more deleterious mental health indicators.