Modelling timing and tempo of adrenarche in a prospective cohort study

To better understand how health risk processes are linked to adrenarche, measures of adrenarcheal timing and tempo are needed. Our objective was to describe and classify adrenal trajectories, in terms of timing and tempo, in a population of children transitioning to adolescence with repeated measurements of salivary dehydroepiandrosterone (DHEA), DHEA-sulphate, and testosterone. We analysed data from the Childhood to Adolescence Transition Study (CATS), a longitudinal study of 1239 participants, recruited at 8-9 years old and followed up annually. Saliva samples were assayed for adrenal hormones. Linear mixed-effect models with subject-specific random intercepts and slopes were used to model longitudinal hormone trajectories by sex and derive measures of adrenarcheal timing and tempo. The median values for all hormones were higher at each consecutive study wave for both sexes, and higher for females than males. For all hormones, between-individual variation in hormone levels at age 9 (timing) was moderately large and similar for females and males. Between-individual variation in hormone progression over time (tempo) was of moderate magnitude compared with the population average age-slope, which itself was small compared with overall hormone level at each age. This suggests that between-individual variation in tempo was less important for modelling hormone trajectories. Between-individual variation in timing was more important for determining relative adrenal hormonal level in childhood than tempo. This finding suggests that adrenal hormonal levels at age 8-9 years can be used to predict relative levels in early adolescence (up to 13 years).

Learning outcomes in primary school children with emotional problems: a prospective cohort study

BACKGROUND

Academic difficulties are common in adolescents with mental health problems. Although earlier childhood emotional problems, characterised by heightened anxiety and depressive symptoms are common forerunners to adolescent mental health problems, the degree to which mental health problems in childhood may contribute independently to academic difficulties has been little explored.

METHODS

Data were drawn from a prospective cohort study of students in Melbourne, Australia (N = 1239). Data were linked with a standardised national assessment of academic performance at baseline (9 years) and wave three (11 years). Depressive and anxiety symptoms were assessed at baseline and wave two (10 years). Regression analyses estimated the association between emotional problems (9 and/or 10 years) and academic performance at 11 years, adjusting for baseline academic performance, sex, age and socioeconomic status, and hyperactivity/inattention symptoms.

RESULTS

Students with depressive symptoms at 9 years of age had lost nearly 4 months of numeracy learning two years later after controlling for baseline academic performance and confounders. Results were similar for anxiety symptoms. Regardless of when depressive symptoms occurred there were consistent associations with poorer numeracy performance at 11 years. The association of depressive symptoms with reading performance was weaker than for numeracy if they were present at wave two. Persistent anxiety symptoms across two waves led to nearly a 4 month loss of numeracy learning at 11 years, but the difference was not meaningful for reading. Findings were similar when including hyperactivity/inattention symptoms.

CONCLUSIONS

Childhood anxiety and depression are not only forerunners of later mental health problems but predict academic achievement. Partnerships between education and health systems have the potential to not only improve childhood emotional problems but also improve learning.

533The psychosocial profiles of children aged 11-12 years who have self-harmed: A prospective cohort study

Background

Self-harm in very young people can be a clinically ominous event. While most studies to date have focused on self-harm during the teenage years, fewer studies have examined children aged 12 years or under. We aimed to estimate the incidence and correlates of recent self-harm in a population-based, non-treatment-seeking sample of primary school-aged children.

Methods

1059 children from 43 primary schools in Melbourne, Australia were interviewed at the age of 8 years (Wave 1), and followed up annually until the age of 11 years (Waves 2-4). Interviews covered a range of physical and mental health, social, educational and family domains, including (at Wave 4) self-harm during the previous 12 months.

Results

At Wave 4 (mean age: 11.9 years), a total of 28 children (3%; 18 girls [3%], 10 boys [2%]) reported self-harming during the previous 12 months. When compared with children who reported no self-harm, they were more likely to report depression, anxiety, poor emotional control, frequent bullying victimisation (including online bullying), truancy, recent alcohol consumption, and antisocial behaviour during Waves 1-3. They were also more likely to report having few friends.

Conclusions

Self-harm was reported by a proportion of community-dwelling children aged 11-12 years. As these children were more likely to report a range of other adverse behaviours, experiences and health conditions, clinicians should consider the possibility of prior self-harm when assessing children presenting with such behaviours and issues.

Key messages

The focus of intervention efforts aimed at preventing and reducing adolescent self-harm should extend to primary school-aged children, with a focus on mental health and peer relationships during the pubertal transition.

Social networking and symptoms of depression and anxiety in early adolescence

BACKGROUND

Use of social networking in later childhood and adolescence has risen quickly. The consequences of these changes for mental health are debated but require further empirical evaluation.

METHODS

Using data from the Childhood to Adolescence Transition Study (n = 1,156), duration of social networking use was measured annually at four time points from 11.9 to 14.8 years of age (≥1 h/day indicating high use). Cross-sectional and prospective relationships between social networking use and depressive and anxiety symptoms were examined.

RESULTS

In adjusted (age, socioeconomic status, prior mental health history) cross-sectional analyses, females with high social networking use had greater odds of depressive (odds ratio [OR]: 2.15; 95% confidence interval [CI]: 1.58-2.91) and anxiety symptoms (OR: 1.99; 95% CI: 1.32-3.00) than those that used a few minutes at most, while males with high social networking use had 1.60 greater odds of reporting depressive symptoms (95% CI: 1.09-2.35). For females, an increased odds of depressive symptoms at age 14.8 was observed for high social networking use at one previous wave and at two or three previous waves, even after adjustment (OR: 1.76; 95% CI: 1.11-2.78; OR: 2.06, 95% CI: 1.27-3.37, respectively) compared to no wave of high use.

CONCLUSIONS

Our results suggest weak to moderate increased odds of depression and anxiety in girls and boys with high social networking use versus low/normal use. These findings indicate that prevention programs for early mental health problems might benefit from targeting social networking use in early adolescence.

Self-harm in primary school-aged children: Prospective cohort study

Introduction

No prospective studies have examined the prevalence, antecedents or concurrent characteristics associated with self-harm in non-treatment-seeking primary school-aged children.

Methods

In this cohort study from Melbourne, Australia we assessed 1239 children annually from age 8–9 years (wave 1) to 11–12 years (wave 4) on a range of health, social, educational and family measures. Past-year self-harm was assessed at wave 4. We estimated the prevalence of self-harm and used multivariable logistic regression to examine associations with concurrent and antecedent factors.

Results

28 participants (3% of the 1059 with self-harm data; 18 girls [3%], 10 boys [2%]) reported self-harm at age 11–12 years. Antecedent (waves 1–3) predictors of self-harm were: persistent symptoms of depression (sex-age-socioeconomic status adjusted odds ratio [aOR]: 7.8; 95% confidence intervals [CI] 2.6 to 24) or anxiety (aOR: 5.1; 95%CI 2.1 to 12), frequent bullying victimisation (aOR: 24.6; 95%CI 3.8 to 158), and recent alcohol consumption (aOR: 2.9; 95%CI 1.2 to 7.1). Concurrent (wave 4) associations with self-harm were: having few friends (aOR: 8.7; 95%CI 3.2 to 24), poor emotional control (aOR: 4.2; 95%CI 1.9 to 9.6), antisocial behaviour (theft—aOR: 3.1; 95%CI 1.2 to 7.9; carrying a weapon—aOR: 6.9; 95%CI 3.1 to 15), and being in mid-puberty (aOR: 6.5; 95%CI 1.5 to 28) or late/post-puberty (aOR: 14.4; 95%CI 2.9 to 70).

Conclusions

The focus of intervention efforts aimed at preventing and reducing adolescent self-harm should extend to primary school-aged children, with a focus on mental health and peer relationships during the pubertal transition.

Electronic media use and academic performance in late childhood: A longitudinal study

INTRODUCTION

The effects of electronic media use on health has received much attention but less is known about links with academic performance. This study prospectively examines the effect of media use on academic performance in late childhood.

MATERIALS AND METHODS

1239 8- to 9-year-olds and their parents were recruited to take part in a prospective, longitudinal study. Academic performance was measured on a national achievement test at baseline and 10-11 years of age. Parents reported on their child's duration of electronic media use.

RESULTS

After control for baseline reading, watching more than two hours of television per day at 8-9 years of age predicted a 12-point lower performance in reading at 10-11 years, equivalent to the loss of a third of a year in learning. Using a computer for more than one hour a day predicted a similar 12-point lower numeracy performance. Regarding cross-sectional associations (presumed to capture short-term effects) of media use on numeracy, after controlling for prior media exposure, watching more than two hours of television per day at 10-11 years was concurrently associated with a 12-point lower numeracy score and using a computer for more than one hour per day with a 13-point lower numeracy performance. There was little evidence for concurrent effects on reading. There was no evidence of short- or long-term associations between videogame use and academic performance.

DISCUSSION

Cumulative television use is associated with poor reading and cumulative computer use with poorer numeracy. Beyond any links between heavy media use and health risks such as obesity, physical activity and mental health, these findings raise a possibility of additional risks of both television and computer use for learning in mid-childhood. These findings carry implications for parents, teachers and clinicians to consider the type and timing of media exposure in developing media plans for children.

Diet quality and mental health problems in late childhood

Objectives: There is evidence that diet quality is associated with mental health problems in adults and adolescents. Yet the extent to which overall diet quality (not individual nutrients or dietary patterns) may be associated with mental health problems in pre-adolescent children, a common time for first onset of symptoms, remains unclear. This study examined associations between overall diet quality, using a brief measure, and mental health problems during late childhood, in a large community sample. Methods: Participants were 787 eight and nine-year-old children taking part in the Childhood to Adolescence Transition Study. Parents reported on their child's mental health problems using the Strengths and Difficulties Questionnaire and on their child's diet quality, using a six-item screening tool. Results: Regression analyses were conducted, adjusting for child age, sex, body mass index, and family socioeconomic status. Overall diet quality was significantly associated with children's mental health before (beta = -0.11, 95% CI -0.18 to -0.04, p = 0.004) and after adjustments for age, sex, body mass index and family socioeconomic status (beta = -0.10, 95% CI -0.18 to -0.03, p = 0.007). Conclusion: Concordant with previous literature, results indicate that better overall diet quality is related to more positive mental health in pre-adolescent children. Additionally, these results support the utility and efficacy of a brief (six-item) parent-report questionnaire as an indicator of overall diet quality.

Peer Victimization and Academic Performance in Primary School Children

OBJECTIVE

Peer victimization is a common antecedent of poor social and emotional adjustment. Its relationship with objectively measured academic performance is unclear. In this study we aimed to quantify the cross-sectional associations between peer victimization and academic performance in a large population sample of children.

METHODS

Eight- to 9-year-old children were recruited from a stratified random sample of primary schools in Australia. Academic performance was measured on a national achievement test (1 year of learning equals 40 points). Physical and verbal victimization were measured according to child self-report.

RESULTS

Multilevel mixed-effects linear regression analyses were conducted. For female children, verbal victimization was associated with poorer academic performance on writing (β = 17.2; 95% confidence interval [CI], -28.2 to -6.2) and grammar/punctuation (β = -20.8; 95% CI, -40.1 to -1.6). Physical victimization was associated with poorer performance on numeracy (male children: β = -29.0; 95% CI, -53.8 to -4.1; female children: β = -30.1; 95% CI, -56.6 to -3.5), and writing (female children: β = -21.5; 95% CI, -40.4 to -2.7). Verbal and physical victimization were associated with poorer performance on reading (male children: β = -31.5; 95% CI, -59.9 to -3.1; female children: β = -30.2; 95% CI, -58.6 to -1.8), writing (female children: β = -25.5; 95% CI, -42.8 to -8.2), spelling (female children: β = -32.3; 95% CI, -59.6 to -4.9), and grammar/punctuation (female children: β = -32.2; 95% CI, -62.4 to -2.0).

CONCLUSIONS

Children who were physically victimized were 6 to 9 months behind their non-victimized peers on measures of academic performance. There are growing reasons for education systems to invest in the prevention of bullying and promotion of positive peer relationships from the earliest years of school.

The Association Between Electronic Media and Emotional and Behavioral Problems in Late Childhood

OBJECTIVE

There is growing concern that rising rates of electronic media use might be harmful. However, the extent to which different types of electronic media use might be associated with emotional and behavioral problems is unclear. In this study we examined associations between emotional and behavioral problems and electronic media use during late childhood, in a large community sample.

METHODS

Participants were 876 8- to 9-year-old children taking part in the Childhood to Adolescence Transition Study in Australia. Parents reported on their child's emotional and behavioral problems using the Strengths and Difficulties Questionnaire and on their child's duration of electronic media use (in hours: television, video games, general computer use).

RESULTS

Logistic regression analyses were conducted with adjustments for age, socioeconomic status, and body mass index z score, separately for male and female participants. Boys who played more video games had significantly greater odds of scoring borderline/abnormal on conduct (odds ratio [OR], 1.07; 95% confidence interval [CI], 1.02-1.12) and emotional problems (OR, 1.07; 95% CI, 1.04-1.11) for each additional hour of weekly use. This equates to 2.58-fold greater odds for a boy who plays on average 2 hours per day per week. Television viewing was associated with greater odds of hyperactivity/inattention in boys (OR, 1.04; 95% CI, 1.00-1.07). There were no significant relationships for girls.

CONCLUSIONS

Because of the increasing rates of electronic media use in children, these results might have important implications for child mental health. Future interventions might be more effective if they are targeted at specific types of electronic media use.

Academic Performance in Primary School Children With Common Emotional and Behavioral Problems

BACKGROUND

Many emotional and behavioral problems first emerge in primary school and are the forerunners of mental health problems occurring in adolescence. However, the extent that these problems may be associated with academic failure has been explored less. We aimed to quantify the association between emotional and behavioral problems with academic performance.

METHODS

A stratified random sample of 8- to 9-year-olds (N = 1239) were recruited from schools in Australia. Data linkage was performed with a national assessment of academic performance to assess reading and numeracy. Parent report assessed emotional and behavioral problems with students dichotomized into "borderline/abnormal" and "normal" categories.

RESULTS

One in 5 grade 3 students fell in the "borderline/abnormal" category. Boys with total difficulties (β = -47.8, 95% CI: -62.8 to -32.8), conduct problems, and peer problems scored lower on reading. Numeracy scores were lower in boys with total difficulties (β = -37.7, 95% CI: -53.9 to -21.5) and emotional symptoms. Children with hyperactivity/inattention scored lower in numeracy. Girls with peer problems scored lower in numeracy.

CONCLUSIONS

Boys with emotional and behavioral problems in mid-primary school were 12 months behind their peers. Children with emotional and behavioral problems are at high risk for academic failure, and this risk is evident in mid-primary school.

Adrenarche and the Emotional and Behavioral Problems of Late Childhood

PURPOSE

Mental and behavioral disorders increase in prevalence with the passage through puberty. Yet the first symptoms for many children emerge between seven and 11 years, before the pubertal rise in gonadal hormones. A possibility that symptom onset may be linked to the adrenarchal rise in androgens has been little explored.

METHODS

The Childhood to Adolescence Transition Study recruited a stratified random sample of 1,239 eight-nine year olds from primary schools in Melbourne, Australia. Saliva samples were assayed for dehydroepiandrosterone, dehydroepiandrosterone-sulphate (DHEA-S), and testosterone. Emotional and behavioral problems were assessed through parental report on the Strengths and Difficulties Questionnaire.

RESULTS

In males, high levels of all androgens were associated with greater total difficulties and peer problems. Higher dehydroepiandrosterone and testosterone were associated with emotional symptoms and DHEA-S with conduct problems. In females, DHEA-S was associated with peer problems.

CONCLUSIONS

In late childhood, androgens are associated with emotional and behavioral problems in males, raising a possibility that the adrenarchal transition plays a contributing role. If so, the late primary school years may prove to be an important phase for preventing the onset of mental health and behavioral problems in boys.

The cost of healthcare for children with mental health difficulties

OBJECTIVE

Childhood mental health difficulties affect one in every seven children in Australia, posing a potential financial burden to society. This paper reports on the early lifetime individual and population non-hospital healthcare costs to the Australian Federal Government for children experiencing mental health difficulties. It also reports on the use and cost of particular categories of service use, including the Medicare Benefits Schedule (MBS) mental health items introduced in 2006.

METHOD

Data from the Longitudinal Study of Australian Children (LSAC) were used to calculate total Medicare costs (government subsidised healthcare attendances and prescription medications) from birth to the 8th birthday associated with childhood mental health difficulties measured to 8-9 years of age.

RESULTS

Costs were higher among children with mental health difficulties than those without difficulties. While individual costs increased with the persistence of difficulties, population-level costs were highest for those with transient mental health difficulties. Although attenuated, these patterns persisted after child, parent and family characteristics were taken into account. Use of the MBS-reimbursed mental health services among children with a mental health difficulty was very low (around 2%).

CONCLUSIONS

Australian healthcare costs for young children with mental health difficulties are substantial and provide further justification for early intervention and prevention. The current provision of Medicare-rebated mental health services does not appear to be reaching young children with mental health difficulties.

Father mental health during the early parenting period: results of an Australian population based longitudinal study

PURPOSE

The primary objective of this study was to report on the occurrence of mental health difficulties for a large national sample of Australian fathers of children aged 0-5 years (n = 3,471). Secondary objectives were to compare fathers' mental health against normative data for the general male adult population, and to examine the course of mental health problems for fathers across the early childhood period.

METHODS

Secondary analysis of data from the infant cohort of the Longitudinal Study of Australian Children at three waves when children were 0-12 months, 2-3 and 4-5 years. Comparative data on the prevalence of psychological distress in the Australian adult male population sourced from the National Survey of Mental Health and Wellbeing.

RESULTS

Approximately nine per cent of fathers reported symptomatic or clinical psychological distress at each wave, as measured by the Kessler-6. Approximately 30 % reporting distress at wave 1 continued to report distress at a similar or worse level across waves 2 and 3. Fathers not living with their children also had high rates of distress (14 % at wave 1 and 10 % at wave 2). Finally, fathers in the present study had 1.38 increased odds (95 % CI 1.12-1.69) for psychological distress compared with the Australian adult male population.

CONCLUSIONS

Fathers are at risk of experiencing postnatal mental health difficulties, which may persist across the early childhood period for some fathers. The results suggest routine assessment of fathers' wellbeing should be undertaken in the postnatal period with mental health interventions and support provided across the early childhood period.

Sleep duration and body mass index in 0-7-year olds

OBJECTIVES

To determine in children aged 0-7 years (1) cross-sectional relationships between body mass index (BMI) and sleep duration, and whether (2) sleep duration predicts later BMI and/or (3) BMI predicts later sleep duration.

DESIGN

Longitudinal Study of Australian Children, Waves 1 and 2.

PARTICIPANTS

Infants aged 0-1 years (Wave 1), followed at age 2-3 years (Wave 2); children aged 4-5 years (Wave 1), followed at age 6-7 years (Wave 2).

MAIN OUTCOME MEASURES

BMI, sleep duration by time-use diary, parent-reported sleep problems (none/mild vs moderate/severe).

ANALYSES

Cross-sectional, ANOVA (sleep duration) and χ(2) (sleep problems); longitudinal, linear regression.

RESULTS

3857 (76%) infants and 3844 (77%) children had BMI and sleep data. At every wave, approximately 15% and 5% of children were overweight and obese, respectively. Obesity was not associated with sleep duration at 0-1, 2-3 or 4-5 years, though obese 6-7-year olds slept approximately 30 min less (p<0.001). Sleep problems were similar across BMI categories at all ages. Wave 1 sleep duration did not predict Wave 2 BMI, nor did Wave 1 BMI predict Wave 2 sleep duration.

CONCLUSIONS

In these large child population cohorts, sleep duration did not predict obesity up to age 6-7 years. Current trials of sleep interventions to prevent or manage obesity in young children may be premature.

Employment conditions and maternal postpartum mental health: results from the Longitudinal Study of Australian Children

Maternal postpartum mental health is influenced by a broad range of risk and protective factors including social circumstances. Forty percent of Australian women resume employment in the first year postpartum, yet poor quality employment (without security, control, flexibility or leave) has not been investigated as a potential social determinant of maternal psychological distress. This paper examines whether poor quality jobs are associated with an increased risk of maternal postpartum psychological distress. Data were collected from employed mothers of infants ≤12 months (n = 1,300) participating in the Longitudinal Study of Australian Children. Logistic regression analyses estimated the association between job quality and maternal psychological distress, adjusting for prior depression, social support, quality of partner relationship, adverse life events and sociodemographic characteristics. Only 21% of women reported access to all four optimal job conditions. After adjustment for known risk factors for poor maternal mood, mothers were significantly more likely to report psychological distress (adjusted OR = 1.39, 95% CI 1.09, 1.77) with each reduction in the number of optimal employment conditions. Interventions for maternal postpartum affective disorders are unlikely to be successful if major risk factors are not addressed. These results provide strong evidence that employment conditions are associated with maternal postpartum mood, and warrant consideration in psychosocial risk assessments and interventions.

Changes in body mass index and health related quality of life from childhood to adolescence

OBJECTIVE

To determine longitudinal relationships between body mass index (BMI) and health-related quality of life (HRQoL) in an adolescent population sample. Design. Data collected in 2000 and 2005 within the Health of Young Victorians longitudinal cohort study.

SETTING

Originally a community sample of elementary school students in Victoria, Australia. Follow-up occurred in either secondary schools or individuals homes.

PARTICIPANTS

Cohort recruited in 1997 via a random sampling design from Victorian elementary schools. Originally comprising 1 943 children, 1 569 (80.8%) participated in 2000 (wave 2, 8-13 years) and 851 (54%) in 2005 (wave 3, 13-19 years). Main outcome measures. In both waves participants and their parents completed the PedsQL, a 23-item child HRQoL measure, and BMI z-scores and status (non-overweight, overweight or obese) were calculated from measured height and weight. Associations were tested cross-sectionally and longitudinally (linear regression, adjusted for baseline values)

RESULTS

A total of 81.6% remained in the same BMI category, while 11.4% and 7.0% moved to higher and lower categories, respectively. Cross-sectional inverse associations between lower PedsQL and higher BMI categories were similar to those for elementary school children. Wave 2 BMI strongly predicted wave 3 BMI and wave 2 PedsQL strongly predicted wave 3 PedsQL. Only parent-reported Total PedsQL score predicted higher subsequent BMI, though this effect was small. Wave 2 BMI did not predict wave 3 PedsQL.

CONCLUSIONS

This novel study confirmed previous cross-sectional associations, but did not provide convincing evidence that BMI is causally associated with falling HRQoL or vice versa across the transition from childhood to adolescence.

Pet ownership and adolescent health: cross-sectional population study

OBJECTIVE

To determine whether adolescent health and well-being are associated with having a pet in the household (any pet, or specifically dogs, cats or horses/ponies) or average daily time spent caring for/playing with pet(s).

METHODS

Design, setting and participants--Cross-sectional data from the third wave of the Health of Young Victorians Study (HOYVS), a school-based population study in Victoria, Australia. Predictors--Adolescent-reported pet ownership and average daily time spent caring for/playing with pet(s). Outcomes--Self-reported quality of life (KIDSCREEN); average 4-day daily physical activity level from a computerised diary; parent-proxy and self-reported physical and psychosocial health status (PedsQL); measured BMI status (not overweight, overweight, obese) and blood pressure. Statistical Analysis--Regression methods, adjusted for socio-demographic factors, and non-parametric methods.

RESULTS

Household pet data were available for 928 adolescents (466 boys; mean age of 15.9 (SD 1.2) years). Most adolescents (88.7%) reported having a pet in their household. Of these, 75.1% reported no activity involving pets over the surveyed days. It appeared that neither owning a pet nor time spent caring for/playing with a pet was related, positively or negatively, to adolescent health or well-being.

CONCLUSIONS

Despite high rates of pet ownership, adolescents had little interaction with pets. It appears that owning a pet and time spent caring for/playing with a pet was not clearly associated with adolescents' health or well-being.

Comorbidities of overweight/obesity experienced in adolescence: longitudinal study

OBJECTIVES

Adolescent obesity is linked to metabolic and cardiovascular risk, but its associations with adolescents' experienced health and morbidity are less clear. Morbidities experienced by overweight/obese adolescents and associations between morbidities and timing of overweight/obesity were examined.

METHODS

Data were from the Health of Young Victorians Study (HOYVS; 1997, 2000, 2005), a school-based longitudinal study. Outcomes were blood pressure, health status (Pediatric Quality of Life Inventory 4.0 (PedsQL), global health), mental health (Strengths and Difficulties Questionnaire), psychological distress (Kessler-10), physical symptoms, sleep, asthma, dieting, and healthcare needs and visits. Regression methods assessed associations with body mass index status and timing of overweight/obesity.

RESULTS

Of the 923 adolescents (20.2% overweight, 6.1% obese), 63.5% were classified as "never" overweight/obese, 8.5% as "childhood only", 7.3% as "adolescence only" and 20.8% as "persistent". Compared to non-overweight, current obesity was associated with lower PedsQL physical summary scores (mean -6.58, 95% CI -9.52 to -3.63) and good/fair/poor global health (OR 3.52, 95% CI 1.95 to 6.36), hypertension (systolic 8.86, 95% CI 4.70 to 16.71; diastolic 5.29, 95% CI 2.74 to 10.20) and dieting (OR 5.79, 95% CI 3.28 to 10.23), with intermediate associations for overweight. Associations with psychosocial morbidity were weaker and inconsistent and there were few associations with health symptoms and problems. Only dieting (OR 2.30, 95% CI 1.36 to 3.89) was associated with resolved childhood overweight/obesity.

CONCLUSIONS

Despite poorer overall health, overweight/obese adolescents were not more likely to report specific problems that might prompt health intervention. Morbidity was mainly associated with concurrent, rather than earlier, overweight/obesity.

Electronic media use and adolescent health and well-being: cross-sectional community study

OBJECTIVE

To describe time adolescents spend using electronic media (television, computer, video games, and telephone); and to examine associations between self-reported health/well-being and daily time spent using electronic media overall and each type of electronic media.

METHODS

Design-Cross-sectional data from the third (2005) wave of the Health of Young Victorians Study, an Australian school-based population study. Outcome Measures-Global health, health-related quality of life (HRQoL; KIDSCREEN), health status (Pediatric Quality of Life Inventory 4.0; PedsQL), depression/anxiety (Kessler-10), and behavior problems (Strengths and Difficulties Questionnaire). Exposure Measures-Duration of electronic media use averaged over 1 to 4 days recalled with the Multimedia Activity Recall for Children and Adolescents (MARCA) computerized time-use diary. Analysis-Linear and logistic regression; adjusted for demographic variables and body mass index z score.

RESULTS

A total of 925 adolescents (mean +/- standard deviation age, 16.1+/-1.2 years) spent, on average, 3 hours 16 minutes per day using electronic media (television, 128 minutes per day; video games, 35; computers, 19; telephone, 13). High overall electronic media use was associated with poorer behavior, health status, and HRQoL. Associations with duration of specific media exposures were mixed; there was a favorable association between computer use (typing/Internet) and psychological distress, whereas high video game use was associated with poorer health status, HRQoL, global health, and depression/anxiety. Television and telephone durations were not associated with any outcome measure.

CONCLUSIONS

Despite television's associations with obesity, time spent in other forms of media use appear more strongly related to adolescent health and well-being. This study supports efforts to reduce high video game use and further exploration of the role of computers in health enhancement.

Problem behaviours and parenting in preschool children with cystic fibrosis

BACKGROUND

Problems with sleep, eating and adherence to therapy may adversely affect health outcomes in children with cystic fibrosis (CF). Data on the prevalence of such problems, associated parenting styles and caregiver mental health are limited.

AIMS

To determine: (a) the prevalence of sleep, mealtime, therapy adherence and externalising and internalising behavioural problems in preschool children with CF; (b) the prevalence of caregiver mental health problems and poor sleep quality; and (c) associations between child behavioural problems and parenting styles.

METHODS

This was a cross sectional survey of caregivers of children aged 6 months to 5 years attending CF outpatient clinics at Royal Children's Hospital (Melbourne), Monash Medical Centre (Melbourne) and Sydney Children's Hospital. Main outcome measures were child externalising and internalising behaviours, sleep, eating and adherence with therapy; the predictor was parenting styles (harsh, inconsistent, overprotective).

RESULTS

117 of 139 families participated. Problems were common with child sleep (small

PROBLEM

31.6%; moderate/large problem: 21.9%), eating (32.4%) and adherence with physiotherapy (50.4%). Compared to normative data, sleep and mealtime problems were more prevalent. Caregivers reported high rates of symptoms indicating depression (33.3%), anxiety (16.4%) and stress (34.2%). Harsh parenting was associated with internalising behaviours (adjusted OR 3.9, 95% CI 1.16 to 13.17, p = 0.03).

CONCLUSIONS

Problems with sleeping, eating and physiotherapy adherence were common in preschool children with CF. Caregivers reported high rates of symptoms indicative of mental health problems. Harsh parenting was associated with internalising problems. An intervention targeting child problem behaviours and parental mental health would be appropriate for CF families.

Outcomes of child sleep problems over the school-transition period: Australian population longitudinal study

BACKGROUND

Adequate sleep optimizes children's learning and behavior. However, the natural history and impact of sleep problems during school transition is unknown.

OBJECTIVES

To determine (1) the natural history of sleep problems over the 2-year period spanning school entry and (2) associations of children's health-related quality of life, language, behavior, learning, and cognition at ages 6.5 to 7.5 years with (a) timing and (b) severity of sleep problems.

METHODS

Data were drawn from the Longitudinal Study of Australian Children. Children were aged 4 to 5 years at wave 1 and 6 to 7 years at wave 2. Parent-reported predictors included (1) timing (none, persistent, resolved, incident) of moderate/severe sleep problems over the 2 waves and (2) severity (none, mild, moderate/severe) of sleep problems at wave 2. Outcomes included parent-reported health-related quality of life and language, parent- and teacher-reported behavior, teacher-reported learning, and directly assessed nonverbal (matrix reasoning) and verbal (receptive vocabulary) cognition. Linear regression, adjusted for child age, gender, and social demographic variables, was used to quantify associations of outcomes with sleep-problem timing and severity.

RESULTS

Sleep data were available at both waves for 4460 (89.5%) children, of whom 22.6% (17.0% mild, 5.7% moderate/severe) had sleep problems at wave 2. From wave 1, 2.9% persisted and 2.8% developed a moderate/severe problem, whereas 10.1% resolved. Compared with no sleep problems, persistent and incident sleep problems predicted poorest health-related quality of life, behavior, language, and learning scores, whereas resolving problems showed intermediate outcomes. These outcomes also showed a dose-response relationship with severity at wave 2, with effect sizes for moderate/severe sleep problems ranging from -0.25 to -1.04 SDs. Cognitive outcomes were unaffected.

CONCLUSIONS

Sleep problems during school transition are common and associated with poorer child outcomes. Randomized, controlled trials could determine if population-based sleep interventions can reduce the prevalence and impact of sleep problems.

Does maternal concern about children's weight affect children's body size perception at the age of 6.5?--A community-based study

OBJECTIVE

Though overweight is often established by school entry, not all mothers of such children report weight concerns. Enhancing concern might assist lifestyle change, but could lead to child body dissatisfaction. We investigated (i) perceived/desired body size and body dissatisfaction in mothers and their 6.5-year-old children, and (ii) the impact of earlier maternal concern about overweight on children's body mass index (BMI) status and body dissatisfaction.

DESIGN

Prospective community study.

SETTING

Melbourne, Australia.

SUBJECTS

317 mother-child dyads.

MAIN EXPOSURES

Child and maternal BMI (kg m(-2)) at 4.0 and 6.5 years; maternal concern about child overweight at 4.0 years.

OUTCOME MEASURES

Paired perceived and desired body size on 7-point figural rating scales self-reported by mothers and children, and reported by mothers regarding children; dissatisfaction ('desired' minus 'perceived') score.

RESULTS

For all three actual BMI perceived size pairings (mother self-report, mother's report on child and child self-report), BMI correlated with perceived body size (r=0.82 (mother self-report); r=0.65 (mother reporting on child); r=0.22 (child self-report); all P<0.001). Similarly, all three dissatisfaction scores were greater with increasing BMI status. Children's own dissatisfaction scores correlated with their actual BMI, but were not related to mothers' own body dissatisfaction scores or with mothers' dissatisfaction with children's body size. Maternal concern about overweight at the age of 4 years was not associated with BMI change, or child body dissatisfaction by the age of 6.5. Most mothers of overweight and obese children (88 and 90%, respectively) regarded their child as the middle figure (that is, 4) or thinner.

CONCLUSIONS

Despite low rates of recognition of child overweight, maternal perceptions of the child's body correlated strongly with the child's actual BMI. Maternal concerns about child BMI did not appear to impact on child BMI change or child body dissatisfaction.

Adverse associations of sleep problems in Australian preschoolers: national population study

OBJECTIVE

In contrast to school-aged children, the impact of sleep problems in preschool-aged children is not well documented. We aimed to determine relationships between preschool-aged child sleep problems and child behavior; health-related quality of life; verbal, preliteracy, and early numeracy skills; diagnosis of attention-deficit/hyperactivity disorder; and injury.

PARTICIPANTS AND METHODS

Participants included families (n = 4983) participating in the first wave of the Longitudinal Study of Australian Children, a nationally representative study of Australian children aged 4 to 5 years surveyed from March to November 2004. Measures consisted of a primary caregiver's report of whether their child had a sleep problem (none versus mild versus moderate/severe); specific sleep patterns occurring > or = 4 nights per week; health-related quality of life (by using the Pediatric Quality of Life Inventory 4.0); behavior (by using the Strengths and Difficulties Questionnaire) and parent-reported diagnosis of attention-deficit/hyperactivity disorder; and injury requiring medical attention in the past 12 months. Tests of receptive vocabulary and preliteracy/numeracy skills (by using the Who Am I? developmental assessment and the adapted Peabody Picture Vocabulary Test, 3rd Edition) were directly administered to each child.

RESULTS

Sleep problems were common, and compared with children without sleep problems, children with sleep problems had poorer child health-related quality of life, more behavior problems, and higher rates of attention-deficit/hyperactivity disorder. Difficulty going to sleep and morning tiredness had greater adverse associations than snoring or night waking.

CONCLUSIONS

Given that sleep problems are very common, the adverse outcomes shown here could affect the transition to school for a very large number of preschoolers.

Overweight, obesity and girth of Australian preschoolers: prevalence and socio-economic correlates

OBJECTIVE

(1) To determine the prevalence of overweight and obesity in Australian 4-5-year-old children. (2) To investigate associations between socio-economic characteristics and (a) overweight/obesity and (b) waist circumference.

DESIGN

Cross-sectional population survey.

SETTING

Wave 1 (2004) of the Longitudinal Study of Australian Children.

PARTICIPANTS

Nationally representative sample of 4983 4-5-year-old children (2537 boys and 2446 girls; mean age 56.9 months (s.d. 2.64 months; range 51-67 months)).

MAIN OUTCOME MEASURES

Prevalence of overweight and obesity (International Obesity TaskForce definitions) and waist circumference (cm).

ANALYSIS

Prevalence estimates were obtained as weighted percentages. Uni- and multivariable ordinal logistic regression (using the proportional odds model) were used to assess associations between potential predictors and the risk of higher child body mass index status and a multivariable linear regression model to assess relationships between the same potential predictors and waist circumference.

RESULTS

15.2% of Australian preschoolers are estimated to be overweight and 5.5% obese. In univariate analyses, seven of the 12 variables were associated with higher odds of being in a heavier body mass index category. In a multivariable regression model, speaking a language other than English (particularly for boys), indigenous status and lower disadvantage quintile were the clearest independent predictors of higher body mass index status, with children in the lowest quintile of social disadvantage having 47% higher odds (95% CI 14, 92%) of being in a heavier body mass index category compared to those in the highest quintile. Waist circumference was not related to any socio-economic variable.

CONCLUSIONS

This nationally representative survey confirms high rates of overweight and obesity in preschoolers throughout Australia. The recent emergence of a substantial socio-economic gradient should bring new urgency to public health measures to combat the obesity epidemic.

Is There a Relationship Between Overweight and Obesity and Mental Health Problems in 4- to 5-Year-Old Australian Children?

OBJECTIVE

To investigate the relationship between overweight and obesity, and mental health problems in Australian 4- to 5-year-old children.

METHODS

The study used data from wave 1 (2004) of the Longitudinal Study of Australian Children (LSAC). The participants were 4983 4- to 5-year-old children (2537 boys and 2446 girls) with a mean age of 56.9 months (standard deviation 2.6 months; range 51-67 months). Children were classified as nonoverweight, overweight, and obese on the basis of International Obesity Task Force definitions. Mental health problems were assessed by the Strengths and Difficulties Questionnaire (SDQ) completed by parents and teachers.

RESULTS

Although obese 4- to 5-year-old boys had more mental health problems than nonoverweight boys, differences between the groups were small and substantially reduced when analyses controlled for children's sociodemographic characteristics. Parents reported that overweight/obese girls had more peer problems, whereas teachers reported they had more conduct problems. Children in all weight groups had mean scores within the normal range of scores on all the SDQ subscales.

CONCLUSIONS

Differences in rates of mental health problems experienced by young children of different weight status appear relatively small. Higher rates of mental health problems experienced by more obese boys may reflect differences in their sociodemographic characteristics rather than their weight status per se. Policies that reduce the number of young children living in poverty or experiencing other adverse social circumstances have the potential to reduce rates of mental health problems experienced by older children with overweight/obesity.

Characterization of presenilin complexes from mouse and human brain using Blue Native gel electrophoresis reveals high expression in embryonic brain and minimal change in complex mobility with pathogenic presenilin mutations

The presenilin proteins are required for intramembrane cleavage of a subset of type 1 membrane proteins including the Alzheimer's disease amyloid precursor protein. Previous studies indicate presenilin proteins form enzymatically active high molecular mass complexes consisting of heterodimers of N- and C-terminal fragments in association with nicastrin, presenilin enhancer-2 and anterior pharynx defective-1 proteins. Using Blue Native gel electrophoresis (BN/PAGE) we have studied endogenous presenilin 1 complex mass, stability and association with nicastrin, presenilin enhancer-2 and anterior pharynx defective-1. Solubilization of mouse or human brain membranes with dodecyl-d-maltoside produced a 360-kDa species reactive with antibodies to presenilin 1. Presenilin 1 complex levels were high in embryonic brain. Complex integrity was sensitive to Triton X-100 and SDS, but stable to reducing agent. Addition of 5 M urea caused complex dissolution and nicastrin to migrate as a subcomplex. Nicastrin and presenilin enhancer-2 were detected in the presenilin 1 complex following BN/PAGE, electroelution and second-dimension analysis. Anterior pharynx defective-1 was detected as an 18-kDa form and 9-kDa C-terminal fragment by standard SDS/PAGE of mouse tissues, and as a predominant 36-kDa band after presenilin 1 complex second-dimension analysis. Membranes from brain cortex of Alzheimer's disease patients, or from cases with presenilin 1 missense mutations, indicated no change in presenilin 1 complex mobility. Higher molecular mass presenilin 1-reactive species were detected in brain containing presenilin 1 exon 9 deletion mutation. This abnormality was confirmed using cells transfected with the same presenilin deletion mutation.

Alternative transcripts of presenilin-1 associated with frontotemporal dementia

We have analyzed the expression of Alzheimer's disease-associated presenilin 1 (PS1) in various neurodegenerative disorders. Western blotting identified PS1 N- and C-terminal fragments similarly in the cortex of controls, Parkinson, Huntington and schizophrenia subjects. Additional PS1 immunoreactive species of 42 and 46 kDa were present in six out of seven cases of sporadic frontotemporal dementia (FTD) and these were particularly prominent in two cases. RT-PCR analysis using nested primers showed the presence of PS1 gene products with deletions within the exon 4-8 region. Our results suggest that alternative transcription of PS1 may be associated with FTD.

Alternative transcripts of presenilin-1 associated with frontotemporal dementia

We have analyzed the expression of Alzheimer's disease-associated presenilin 1 (PS1) in various neurodegenerative disorders. Western blotting identified PS1 N- and C-terminal fragments similarly in the cortex of controls, Parkinson, Huntington and schizophrenia subjects. Additional PS1 immunoreactive species of 42 and 46 kDa were present in six out of seven cases of sporadic frontotemporal dementia (FTD) and these were particularly prominent in two cases. RT-PCR analysis using nested primers showed the presence of PS1 gene products with deletions within the exon 4-8 region. Our results suggest that alternative transcription of PS1 may be associated with FTD.