Associations between demographic characteristics, school schedules, activity choices, family functioning, and sleep behaviors were estimated using, nationally representative time-diary data from 2,454 children (ages 5.5 to 11.9 years) and adolescents (ages 12.0 to 19.1 years). For weekdays, African American adolescents, Asian children, and those with earlier school start times and longer travel times to school reported fewer sleep hours. More time spent watching television (for children), doing homework (for adolescents), and engaging in religious activities predicted fewer hours, whereas a longer time spent on meals predicted greater hours of weekday sleep. For younger children, greater parental warmth predicted more hours of weekday sleep, whereas for adolescents, stricter household rules were protective. On weekends, African American adolescents and Hispanic children slept less, and there were strong effects of activity choices including time spent on television, computer and video-games, sports, religious activities, socializing, and employment. In accounting for age-related decreases in sleep hours from childhood to adolescence, earlier school start times, greater hours of homework, greater paid employment, less time spent on meals, and fewer household rules were all significant mediators. Read more...

Objective: The authors examined national trends from 1990 to 2000 in the utilization of community hospital inpatient services by young people (5-20 years of age) with intentional self-inflicted injuries. Method: Discharge abstracts from a nationally representative sample of community hospitals were analyzed, with a focus on youth discharges (N = 10,831) with a diagnosis of intentional self-inflicted injury (ICD-9-CM: E950-E959). Census data were used to derive national population-based rates of self-inflicted injuries requiring inpatient treatment. Overall population-based trends in hospitalizations for self-inflicted injury were calculated and stratified by gender and age. Among youths hospitalized with a self-inflicted injury, trends were also calculated for length of stay, inpatient costs, method of injury, and associated mental disorder diagnoses. Results: The annual hospitalization rate of youths with self-inflicted injuries declined from 49.1 per 100,000 in 1990 to 44.9 per 100,000 in 2000, and the mean length of inpatient stay significantly declined from 3.6 days to 2.7 days. Among the hospitalized patients, there were increases in the rate of cutting (4.3% to 13.2%) and ingestion of acetaminophen (22.1% to 26.9%), antidepressants (10.0% to 14.0%), and opiates (2.3% to 3.3%) as a cause of injury, whereas there were decreases in the ingestion of salicylates (14.9% to 10.2%) and barbiturates (1.5% to 0.7%). There were significant increases in the proportion of subjects with primary mental disorder discharge diagnoses of depressive disorder (29.2% to 46.0%), bipolar disorder (1.3% to 8.2%), and substance use disorder (5.4% to 10.7%) and significant decreases in the rate of adjustment disorders (22.2% to 11.4%) and non-mental disorders (31.9% to 13.6%). After excluding cutting, which may be more closely related to self-mutilation than suicidal self-injury, the annual hospitalization rate of youths with self-inflicted injuries declined from 47.2 per 100,000 in 1990 to 39.4 per 100,000 in 2000. Conclusions: Over the decade of study, young people admitted to community hospitals with self-inflicted injuries tended to have more severe psychiatric diagnoses and to be treated during shorter inpatient stays. These trends suggest that the role of youth inpatient care has narrowed, becoming focused on those with severe psychiatric disorders. Read more...

Background and Objective: Waist circumference (W) has been shown to be a good predictor of cardiovascular risk. The aim of this study was to investigate whether physical activity (PA) is related to W in adolescents as previously shown in adults. Design and Subjects: Cross-sectional population-based survey of 2714 12-y-old adolescents from the eastern part of France. MEASUREMENTS: Body mass index (BMI) and W were measured. Structured PA, active commuting to and from school and sedentary activities (SED), for example television viewing, computer/video games and reading and different potential confounders (dietary habits, parental overweight, family annual income tax and educational level) were assessed by a questionnaire. Results: The adolescents had a mean BMI of 19.0+/-3.4 kg/m(2), and 20.2% of them were overweight, with no gender difference. Boys had a greater W than girls (67.6+/-9.1 vs 65.7+/-8.9 cm, P<0.0001). In all, 42% of the girls and 25% of the boys did not practice any structured PA outside school and less than 40% of the adolescents commuted actively to school more than 20 min/day. About one-third of the adolescents devoted more than 2 h/day to SED. In univariate analyses, BMI was negatively associated with structured PA but significantly only for girls (P<0.01) and positively associated with SED for both genders (P<0.0001 for girls, P<0.01 for boys). W was negatively associated with structured PA and positively associated with SED both in girls (P<0.0001 and P=0.03, respectively) and boys (P<0.01 and P=0.08, respectively). Multiple general linear models show that SED is associated with BMI, independently of structured PA, in both genders. On the other hand, structured PA was inversely associated with W, independently of SED. The inverse relation between structured PA and W persisted after additional adjustment on BMI, with a greater effect of PA for the adolescents with higher BMI. Conclusions: In 12-y-old adolescents, structured PA is inversely associated with W, an indicator of total adiposity but also more specifically of abdominal fat. This suggests that PA may have a beneficial effect on youth metabolic and cardiovascular risks, in particular in the presence of overweight. Read more...

Objective: To assess the relationship between short sleep duration and obesity-related variables in children involved in the 'Quebec en Forme' Project. Design: Cross-sectional study. Subjects: A total of 422 children (211 boys and 211 girls) aged between 5 and 10 years from primary schools in the City of Trois-Rivieres (Quebec) were selected to participate in this study. Measurements: Body weight, height and waist circumference were measured. The children were classified as normal, underweight, overweight or obese, according to body mass index (BMI) per age. An exhaustive questionnaire was administered by telephone to the parents of children. Results: The percentage of overweight/obesity was 20.0% in boys and 24.0% in girls. When compared to children reporting 12-13 h of sleep per day, the adjusted odds ratio for childhood overweight/obesity was 1.42 (95% confidence interval 1.09-1.98) for those with 10.5-11.5 h of sleep and 3.45 (2.61-4.67) for those with 8-10 h of sleep after adjustment for age, sex, and other risk factors. Parental obesity, low parental educational level, low total family income, long hours of TV watching, playing videogames or computer utilization, absence of breastfeeding and physical inactivity were also significantly associated with childhood overweight/obesity. In addition, we observed a significant negative association adjusted for age between sleep duration and body weight (-0.33, P < 0.01), BMI (-0.12, P < 0.01) and waist circumference (-0.24, P < 0.01) in boys. Conclusion: An inverse association was observed between sleep duration and the risk to develop childhood overweight/obesity. Longitudinal research will be required to confirm a potential link of causality between these variables. Read more...