Physical activity, leisure-time screen use and depression among children and young adolescents

OBJECTIVES

Adolescent mental disorders remain a relatively neglected area of research, despite evidence that these conditions affect youth disproportionately. We examined associations between physical activity, leisure-time screen use and depressive symptoms among Australian children and adolescents.

DESIGN

Large cross-sectional observational study.

METHODS

Self-reported physical activity and leisure-time screen behaviours, and depressive symptoms using the Short Mood and Feeling Questionnaire were assessed in 8256 students aged 10-16 years (mean age=11.5 years, SD=0.8).

RESULTS

Thirty three percent of the sample reported moderate to high depressive symptoms, with rates higher among females (OR=1.18; 95% CI: 1.02, 1.36; p=0.001). Increased opportunities to be active at school outside class (OR=0.70; 0.58, 0.85; p<0.001), being active in physical education classes (OR=0.77; 0.69, 0.86; p<0.001), greater involvement in sports teams at school (OR=0.77; 0.67, 0.88; p<0.001) and outside of school (OR=0.84; 0.73, 0.96; p=0.01) were all independently associated with lower odds for depressive symptoms. Meeting recommended guidelines for physical activity (OR=0.62; 0.44, 0.88; p=0.007) and, for 12-14 year olds, leisure-time screen use (OR=0.77; 0.59, 0.99; p=0.04) were also independently associated with lower odds for depressive symptoms.

CONCLUSIONS

Higher levels of physical activity among children and young adolescents, and lower levels of leisure-time screen use among young adolescents, are associated with lower depressive symptoms. Longitudinal studies are needed to understand the causal relationships between these variables.

The persistence of the association between adolescent cannabis use and common mental disorders into young adulthood

AIMS

Debate continues about whether the association between cannabis use in adolescence and common mental disorders is causal. Most reports have focused on associations in adolescence, with few studies extending into adulthood. We examine the association from adolescence until the age of 29 years in a representative prospective cohort of young Australians.

DESIGN

Nine-wave, 15-year representative longitudinal cohort study, with six waves of data collection in adolescence (mean age 14.9-17.4 years) and three in young adulthood (mean age 20.7, 24.1 and 29.1 years).

PARTICIPANTS

Participants were a cohort of 1943 recruited in secondary school and surveyed at each wave when possible from mid-teen age to their late 20s.

SETTING

Victoria, Australia.

MEASUREMENTS

Psychiatric morbidity was assessed with the Revised Clinical Interview Schedule (CIS-R) at each adolescent wave, and as Composite International Diagnostic Interview (CIDI)-defined ICD-10 major depressive episode and anxiety disorder at 29 years. Frequency of cannabis use was measured in the past 6 months in adolescence. Cannabis use frequency in the last year and DSM-IV cannabis dependence were assessed at 29 years. Cross-sectional and prospective associations of these outcomes with cannabis use and dependence were estimated as odds ratios (OR), using multivariable logistic regression models, with the outcomes of interest, major depressive episode (MDE) and anxiety disorder (AD) at 29 years.

FINDINGS

There were no consistent associations between adolescent cannabis use and depression at age 29 years. Daily cannabis use was associated with anxiety disorder at 29 years [adjusted OR 2.5, 95% confidence interval (CI):< 1.2-5.2], as was cannabis dependence (adjusted OR 2.2, 95% CI: 1.1-4.4). Among weekly+ adolescent cannabis users, those who continued to use cannabis use daily at 29 years remained at significantly increased odds of anxiety disorder (adjusted OR 3.2, 95% CI: 1.1-9.2).

CONCLUSIONS

Regular (particularly daily) adolescent cannabis use is associated consistently with anxiety, but not depressive disorder, in adolescence and late young adulthood, even among regular users who then cease using the drug. It is possible that early cannabis exposure causes enduring mental health risks in the general cannabis-using adolescent population.

Using a mobile phone application in youth mental health - an evaluation study

BACKGROUND

This study evaluates a mobile phone self monitoring tool designed to assist paediatricians in assessing and managing youth mental health.

METHODS

Patients from an adolescent outpatient clinic monitored mental health symptoms throughout each day for 2-4 weeks. Paediatricians specialising in adolescent health and participants reviewed the collated data displayed online and completed quantitative and qualitative feedback.

RESULTS

Forty-seven adolescents and six paediatricians participated. Completion was high, with 91% of entries completed in the first week. Paediatricians found the program helpful for 92% of the participants and understood 88% of their patients' functioning better. Participants reported the data reflected their actual experiences (88%) and was accurate (85%), helpful (65%) and assisted their paediatrician to understand them better (77%). Qualitative results supported these findings.

DISCUSSION

Self monitoring facilitates communication of mental health issues between these paediatricians and patients and is a promising tool for the assessment and management of mental health problems in young people.

The persistence of the association between adolescent cannabis use and common mental disorders into young adulthood

AIMS

Debate continues about whether the association between cannabis use in adolescence and common mental disorders is causal. Most reports have focused on associations in adolescence, with few studies extending into adulthood. We examine the association from adolescence until the age of 29 years in a representative prospective cohort of young Australians.

DESIGN

Nine-wave, 15-year representative longitudinal cohort study, with six waves of data collection in adolescence (mean age 14.9-17.4 years) and three in young adulthood (mean age 20.7, 24.1 and 29.1 years).

PARTICIPANTS

Participants were a cohort of 1943 recruited in secondary school and surveyed at each wave when possible from mid-teen age to their late 20s.

SETTING

Victoria, Australia.

MEASUREMENTS

Psychiatric morbidity was assessed with the Revised Clinical Interview Schedule (CIS-R) at each adolescent wave, and as Composite International Diagnostic Interview (CIDI)-defined ICD-10 major depressive episode and anxiety disorder at 29 years. Frequency of cannabis use was measured in the past 6 months in adolescence. Cannabis use frequency in the last year and DSM-IV cannabis dependence were assessed at 29 years. Cross-sectional and prospective associations of these outcomes with cannabis use and dependence were estimated as odds ratios (OR), using multivariable logistic regression models, with the outcomes of interest, major depressive episode (MDE) and anxiety disorder (AD) at 29 years.

FINDINGS

There were no consistent associations between adolescent cannabis use and depression at age 29 years. Daily cannabis use was associated with anxiety disorder at 29 years [adjusted OR 2.5, 95% confidence interval (CI):< 1.2-5.2], as was cannabis dependence (adjusted OR 2.2, 95% CI: 1.1-4.4). Among weekly+ adolescent cannabis users, those who continued to use cannabis use daily at 29 years remained at significantly increased odds of anxiety disorder (adjusted OR 3.2, 95% CI: 1.1-9.2).

CONCLUSIONS

Regular (particularly daily) adolescent cannabis use is associated consistently with anxiety, but not depressive disorder, in adolescence and late young adulthood, even among regular users who then cease using the drug. It is possible that early cannabis exposure causes enduring mental health risks in the general cannabis-using adolescent population.

Health of the world's adolescents: a synthesis of internationally comparable data

Adolescence and young adulthood offer opportunities for health gains both through prevention and early clinical intervention. Yet development of health information systems to support this work has been weak and so far lagged behind those for early childhood and adulthood. With falls in the number of deaths in earlier childhood in many countries and a shifting emphasis to non-communicable disease risks, injuries, and mental health, there are good reasons to assess the present sources of health information for young people. We derive indicators from the conceptual framework for the Series on adolescent health and assess the available data to describe them. We selected indicators for their public health importance and their coverage of major health outcomes in young people, health risk behaviours and states, risk and protective factors, social role transitions relevant to health, and health service inputs. We then specify definitions that maximise international comparability. Even with this optimisation of data usage, only seven of the 25 indicators, covered at least 50% of the world's adolescents. The worst adolescent health profiles are in sub-Saharan Africa, with persisting high mortality from maternal and infectious causes. Risks for non-communicable diseases are spreading rapidly, with the highest rates of tobacco use and overweight, and lowest rates of physical activity, predominantly in adolescents living in low-income and middle-income countries. Even for present global health agendas, such as HIV infection and maternal mortality, data sources are incomplete for adolescents. We propose a series of steps that include better coordination and use of data collected across countries, greater harmonisation of school-based surveys, further development of strategies for socially marginalised youth, targeted research into the validity and use of these health indicators, advocating for adolescent-health information within new global health initiatives, and a recommendation that every country produce a regular report on the health of its adolescents.

Adolescence: a foundation for future health

Adolescence is a life phase in which the opportunities for health are great and future patterns of adult health are established. Health in adolescence is the result of interactions between prenatal and early childhood development and the specific biological and social-role changes that accompany puberty, shaped by social determinants and risk and protective factors that affect the uptake of health-related behaviours. The shape of adolescence is rapidly changing-the age of onset of puberty is decreasing and the age at which mature social roles are achieved is rising. New understandings of the diverse and dynamic effects on adolescent health include insights into the effects of puberty and brain development, together with social media. A focus on adolescence is central to the success of many public health agendas, including the Millennium Development Goals aiming to reduce child and maternal mortality and HIV/AIDS, and the more recent emphases on mental health, injuries, and non-communicable diseases. Greater attention to adolescence is needed within each of these public health domains if global health targets are to be met. Strategies that place the adolescent years centre stage-rather than focusing only on specific health agendas-provide important opportunities to improve health, both in adolescence and later in life.

Very young adolescents and alcohol: evidence of a unique susceptibility to peer alcohol use

AIM

The aim of this study is to examine the susceptibility of very young adolescents (10-12 years of age) to peer alcohol-related influences, compared to older adolescents (13-14 years of age).

METHODS

The analysis sample consisted of 7064 adolescents in grade 6 (modal age 11) or grade 8 (modal age 13) from 231 schools in 30 communities across three Australian States. Key measures were adolescent reports of alcohol use (past 30 days) and the number of peers who consume alcohol without their parent's awareness. Control variables included parent alcohol use, family relationship quality, pubertal advancement, school connectedness, sensation seeking, depression, length of time in high school, as well as age, gender, father/mother education, and language spoken at home. A multi-level model of alcohol use was used to account for school-level clustering on the dependent variable.

RESULTS

For both groups, the number of peers who consumed alcohol was associated with alcohol use, but Grade 6 students showed a unique susceptibility to peripheral involvement with peer drinking networks (having one friend who consumed alcohol).

CONCLUSION

The results point to the importance of monitoring and responding to comparatively minor shifts in the proportion of peers who use alcohol, particularly among very young adolescents.

Adolescent depressive symptoms and subsequent pregnancy, pregnancy completion and pregnancy termination in young adulthood: findings from the victorian adolescent health cohort study

STUDY OBJECTIVE

To examine relationships between depressive symptoms in adolescence (14-18 years of age) and becoming pregnant, completing a pregnancy (live birth) and terminating a pregnancy in young adulthood (21-24 years of age).

PARTICIPANTS AND DESIGN

Data from 1000 females were drawn from a larger sample of 1943 young Australians participating in a longitudinal study of adolescent health and development, followed across 8 waves from adolescence (waves 1-6) to young adulthood (waves 7 and 8).

SETTING

Victoria, Australia.

MAIN OUTCOME MEASURES

Pregnancy, pregnancy completion and pregnancy termination between 21-24 years of age.

RESULTS

We observed a twofold increase in the odds of becoming pregnant in those reporting persisting patterns of depressive symptoms during adolescence (2+ waves); however, after staged adjustment for adolescent antisocial behaviour, drug use and socioeconomic disadvantage, there was no evidence of association. Of particular note, and consistent with previous research, adolescent antisocial and drug use behavior were strongly associated with becoming pregnant and pregnancy termination in young adulthood.

CONCLUSIONS

Adolescent antisocial and drug use behavior, not depressive symptoms, independently predict pregnancy outcomes in young adulthood.

The natural history of self-harm from adolescence to young adulthood: a population-based cohort study

BACKGROUND

Knowledge about the natural history of self-harm is scarce, especially during the transition from adolescence to young adulthood, a period characterised by a sharp rise in self-inflicted deaths. From a repeated measures cohort of a representative sample, we describe the course of self-harm from middle adolescence to young adulthood.

METHODS

A stratified, random sample of 1943 adolescents was recruited from 44 schools across the state of Victoria, Australia, between August, 1992, and January, 2008. We obtained data pertaining to self-harm from questionnaires and telephone interviews at seven waves of follow-up, commencing at mean age 15·9 years (SD 0·49) and ending at mean age 29·0 years (SD 0·59). Summary adolescent measures (waves three to six) were obtained for cannabis use, cigarette smoking, high-risk alcohol use, depression and anxiety, antisocial behaviour and parental separation or divorce.

FINDINGS

1802 participants responded in the adolescent phase, with 149 (8%) reporting self-harm, More girls (95/947 [10%]) than boys (54/855 [6%]) reported self-harm (risk ratio 1·6, 95% CI 1·2-2·2). We recorded a substantial reduction in the frequency of self-harm during late adolescence. 122 of 1652 (7%) participants who reported self-harm during adolescence reported no further self-harm in young adulthood, with a stronger continuity in girls (13/888) than boys (1/764). During adolescence, incident self-harm was independently associated with symptoms of depression and anxiety (HR 3·7, 95% CI 2·4-5·9), antisocial behaviour (1·9, 1·1-3·4), high-risk alcohol use (2·1, 1·2-3·7), cannabis use (2·4, 1·4-4·4), and cigarette smoking (1·8, 1·0-3·1). Adolescent symptoms of depression and anxiety were clearly associated with incident self-harm in young adulthood (5·9, 2·2-16).

INTERPRETATION

Most self-harming behaviour in adolescents resolves spontaneously. The early detection and treatment of common mental disorders during adolescence might constitute an important and hitherto unrecognised component of suicide prevention in young adults.

FUNDING

National Health and Medical Research Council, Australia, and operational infrastructure support programme, Government of Victoria, Australia.

A mobile phone application for the assessment and management of youth mental health problems in primary care: a randomised controlled trial

BACKGROUND

Over 75% of mental health problems begin in adolescence and primary care has been identified as the target setting for mental health intervention by the World Health Organisation. The mobiletype program is a mental health assessment and management mobile phone application which monitors mood, stress, coping strategies, activities, eating, sleeping, exercise patterns, and alcohol and cannabis use at least daily, and transmits this information to general practitioners (GPs) via a secure website in summary format for medical review.

METHODS

We conducted a randomised controlled trial in primary care to examine the mental health benefits of the mobiletype program. Patients aged 14 to 24 years were recruited from rural and metropolitan general practices. GPs identified and referred eligible participants (those with mild or more mental health concerns) who were randomly assigned to either the intervention group (where mood, stress, and daily activities were monitored) or the attention comparison group (where only daily activities were monitored). Both groups self-monitored for 2 to 4 weeks and reviewed the monitoring data with their GP. GPs, participants, and researchers were blind to group allocation at randomisation. Participants completed pre-, post-, and 6-week post-test measures of the Depression, Anxiety, Stress Scale and an Emotional Self Awareness (ESA) Scale.

RESULTS

Of the 163 participants assessed for eligibility, 118 were randomised and 114 participants were included in analyses (intervention group n = 68, comparison group n = 46). Mixed model analyses revealed a significant group by time interaction on ESA with a medium size of effect suggesting that the mobiletype program significantly increases ESA compared to an attention comparison. There was no significant group by time interaction for depression, anxiety, or stress, but a medium to large significant main effect for time for each of these mental health measures. Post-hoc analyses suggested that participation in the RCT lead to enhanced GP mental health care at pre-test and improved mental health outcomes.

CONCLUSIONS

Monitoring mental health symptoms appears to increase ESA and implementing a mental health program in primary care and providing frequent reminders, clinical resources, and support to GPs substantially improved mental health outcomes for the sample as a whole.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00794222.

Predicting future depression in adolescents using the Short Mood and Feelings Questionnaire: a two-nation study

BACKGROUND

Adolescence is a key life period for the development of depression. Predicting the development of depression in adolescence through detecting specific early symptoms may aid in the development of timely screening and intervention programmes.

METHODS

We administered the Short Mood and Feelings Questionnaire (SMFQ) to 5769 American and Australian students aged 10 to 15 years, at two time points, separated by 12 months. We attempted to predict high levels of depression symptoms at 12 months from symptoms at baseline, using statistical approaches based upon the quality, as well as the quantity, of depression symptoms present. These approaches included classification and regression trees (CART) and logistic regression.

RESULTS

A classification tree employing four SMFQ items, such as feelings of self-hatred and of being unloved, performed almost as well as all 13 SMFQ items at predicting subsequent depression symptomatology.

LIMITATIONS

Depression was measured using a self-report instrument, rather than a criterion standard diagnostic interview.

CONCLUSION

Further validation on other populations of adolescents is required: however the results suggest that several symptoms of depression, especially feelings of self-hatred, and being unloved, are associated with increased levels of self-reported depression at 12 months post baseline. Although screening for depression can be problematic, symptoms such as the ones above should be considered for inclusion in screening tests for adolescents.

Association of adolescent symptoms of depression and anxiety with alcohol use disorders in young adulthood: findings from the Victorian Adolescent Health Cohort Study

OBJECTIVE

To examine the association of adolescent depression and anxiety symptoms with alcohol abuse or dependence in young adulthood.

DESIGN, SETTING AND PARTICIPANTS

Cohort study of the health and wellbeing of adolescents and young adults in Victoria, assessed at 8 waves (periods) of data collection, from age 14 to 24 years, between 1992 and 2003. Young people who participated in the cohort study at least once during the six adolescent assessment points (conducted 6 months apart, from age 14 to 17 years), at least once during young adulthood and who were alive at Wave 8 (n = 1758).

MAIN OUTCOME MEASURE

Alcohol abuse or dependence assessed using the alcohol and substance abuse modules of the Composite International Diagnostic Interview at age 24 years.

RESULTS

Adolescents with moderate to high levels of depression and anxiety symptoms (measured by the revised Clinical Interview Schedule) had an increased risk of alcohol abuse or dependence in young adulthood, compared with young adults with low levels of adolescent depression and anxiety symptoms, after adjusting for potential confounding factors. Risk was higher for those with symptoms at more than two adolescent assessment points (odds ratio [OR] 1.9; 95% CI, 1.7-2.0) and for those with symptoms at one or two assessment points (OR 1.3; 95% CI, 1.2-1.4), compared with those with no above-threshold symptoms in adolescence.

CONCLUSIONS

Adolescents with depression and anxiety symptoms are at increased risk for alcohol use disorders into young adulthood. They warrant vigilance from primary care providers in relation to alcohol use well into adulthood.

Risk and protective factors for adolescent substance use in washington state, the United States and Victoria, Australia: a longitudinal study

PURPOSE

To compare the levels of risk and protective factors and the predictive influence of these factors on alcohol, tobacco, and cannabis use over a 12-month follow-up period in Washington State in the United States and in Victoria, Australia.

METHOD

The study involved a longitudinal school-based survey of students drawn as a two-stage cluster sample recruited through schools, and administered in the years 2002 and 2003 in both states. The study used statewide representative samples of students in the seventh and ninth grades (n = 3,876) in Washington State and Victoria.

RESULTS

Washington State students, relative to Victorian students, had higher rates of cannabis use but lower rates of alcohol and tobacco use at time 1. Levels of risk and protective factors showed few but important differences that contribute to the explanation of differences in substance use; Washington State students, relative to Victorian students, reported higher religiosity (odds ratio, .96 vs. .79) and availability of handguns (odds ratio, 1.23 vs. 1.18), but less favorable peer, community, and parental attitudes to substance use. The associations with substance use at follow-up are generally comparable, but in many instances were weaker in Washington State.

CONCLUSIONS

Levels of risk and protective factors and their associations with substance use at follow-up were mostly similar in the two states. Further high-quality longitudinal studies to establish invariance in the relations between risk and protective factors and substance use in adolescence across diverse countries are warranted.

The influence of parents, siblings and peers on pre- and early-teen smoking: a multilevel model

INTRODUCTION AND AIMS

Despite considerable success in tobacco control, many teenagers in Australia and other industrialised countries still smoke tobacco. There is mixed evidence on the relative influence of proximal social networks (parents/siblings/peers) on pre- and early-teen smoking, and no research has examined how these influences compare after accounting for school- and community-level effects.The aim of this study was to compare the relative influences of parents, siblings and peers, after accounting for school- and community-level variation in smoking.

DESIGN AND METHODS

A cross-sectional fixed and random effects model of smoking prevalence was used, with individuals (n = 7314) nested within schools (n = 231) nested within communities (n = 30). Grade 6 and 8 students (modal ages 11 and 13 years) completed an on-line survey. Key variables included parent/sibling/peer use. Controls included alcohol involvement, sensation seeking, pro-social beliefs, laws/norms about substance use and school commitment.

RESULTS

There was significant variation in smoking at both the school and community levels, supporting the need for a multilevel model. Individual-level predictors accounted for much of the variance at higher levels. The strongest effects were for number of friends who smoke, sibling smoking and alcohol involvement. Smaller significant effects were found for parent smoking. At the community level, socioeconomic disadvantage was significant, but community-level variance in pro-social and drug-related laws/norms was not related to smoking.

DISCUSSION AND CONCLUSIONS

Cross-level interactions were generally non-significant. Early teenage smoking was best explained by sibling and peer smoking, and individual risks largely accounted for the substantial variation observed across schools and communities. In terms of future tobacco control, findings point to the utility of targeting families in disadvantaged communities.

Global burden of disease in young people aged 10-24 years: a systematic analysis

BACKGROUND

Young people aged 10-24 years represent 27% of the world's population. Although important health problems and risk factors for disease in later life emerge in these years, the contribution to the global burden of disease is unknown. We describe the global burden of disease arising in young people and the contribution of risk factors to that burden.

METHODS

We used data from WHO's 2004 Global Burden of Disease study. Cause-specific disability-adjusted life-years (DALYs) for young people aged 10-24 years were estimated by WHO region on the basis of available data for incidence, prevalence, severity, and mortality. WHO member states were classified into low-income, middle-income, and high-income countries, and into WHO regions. We estimated DALYs attributable to specific global health risk factors using the comparative risk assessment method. DALYs were divided into years of life lost because of premature mortality (YLLs) and years lost because of disability (YLDs), and are presented for regions by sex and by 5-year age groups.

FINDINGS

The total number of incident DALYs in those aged 10-24 years was about 236 million, representing 15·5% of total DALYs for all age groups. Africa had the highest rate of DALYs for this age group, which was 2·5 times greater than in high-income countries (208 vs 82 DALYs per 1000 population). Across regions, DALY rates were 12% higher in girls than in boys between 15 and 19 years (137 vs 153). Worldwide, the three main causes of YLDs for 10-24-year-olds were neuropsychiatric disorders (45%), unintentional injuries (12%), and infectious and parasitic diseases (10%). The main risk factors for incident DALYs in 10-24-year-olds were alcohol (7% of DALYs), unsafe sex (4%), iron deficiency (3%), lack of contraception (2%), and illicit drug use (2%).

INTERPRETATION

The health of young people has been largely neglected in global public health because this age group is perceived as healthy. However, opportunities for prevention of disease and injury in this age group are not fully exploited. The findings from this study suggest that adolescent health would benefit from increased public health attention.

FUNDING

None.

Childhood sexual abuse and abnormal personality: a population-based study

BACKGROUND

Childhood sexual abuse (CSA) has been shown to be a risk factor for personality disorder (PD). However, no previous studies have examined whether associations exist between sexual abuse and abnormal personality as measured both categorically and dimensionally. Such enquiry would more fully illuminate the impact of CSA on adult personality.

METHOD

Using a large nationally representative sample, we set out to examine associations between CSA and categorically defined PD. We also examined associations between CSA and the five dimensions of personality (openness to experience, conscientiousness, extraversion, agreeableness and neuroticism). A total of 1520 young adults were interviewed to determine the prevalence of sexual abuse occurring before age 16 years. A dimensional measure of personality was completed by 1469 participants, and 1145 had an informant-based PD assessment.

RESULTS

PD was independently associated with repeated CSA [fully adjusted odds ratio (OR) 1.9, 95% confidence interval (CI) 1.1-3.4]. Repeated sexual abuse was also associated with higher neuroticism and lower agreeableness (p values for both <0.001). Adjusting for the effects of potential confounders and mediators, including earlier symptoms of anxiety and depression, had little impact on the strength of associations.

CONCLUSIONS

We conclude that repeated CSA is independently associated with categorically defined PD, and also with higher neuroticism and lower agreeableness. Our findings suggest that if a dimensional classification of PDs is adopted in future classification systems, there might be meaningful continuity with previous aetiological research conducted using the current categorical system.

What are the major drivers of prevalent disability burden in young Australians?

OBJECTIVE

To examine age and sex differences in the leading causes of prevalent disability in young Australians.

DESIGN, SETTING AND PARTICIPANTS

We analysed data from the 2003 Australian Burden of Disease and Injury Study, which estimated the prevalent disability burden attributable to 170 diseases and injuries, for younger adolescents (10-14 years), older adolescents (15-19 years) and young adults (20-24 years).

MAIN OUTCOME MEASURES

The broad categories of disease and injury that are the main contributors to prevalent disability and the 10 leading disease and injury causes of prevalent disability, according to sex and age group.

RESULTS

Total prevalent disability rates are lowest in younger adolescents and highest in young adults. Mental disorders are the largest "contributor" to disability in young Australians, and anxiety and depressive disorders are the leading single cause. In young males, autism and attention deficit hyperactivity disorder cause similar levels of disability as do anxiety and depression. In young females, eating disorders are the second leading cause of mental disorder disability. Alcohol use disorders and schizophrenia make important contributions to disability in young adult males. Asthma is the most prominent cause of physical disability in all three age groups.

CONCLUSIONS

There are substantial changes in both the pattern and level of disability burden across the three age groups that we studied. The increase in total prevalent disability that occurs from early adolescence to young adulthood should focus attention on the delivery of accessible and youth friendly health care as well as the effectiveness of transitions from child health services to adult health services.

Early age alcohol use and later alcohol problems in adolescents: individual and peer mediators in a bi-national study

This paper examines whether there is cross-national similarity in the longitudinal relationship between early age alcohol use and adolescent alcohol problems. Potential mechanisms underlying this relationship also are examined, testing adolescent alcohol use, low self-regulation, and peer deviance as possible mediators. Students (N = 1,945) participating in the International Youth Development Study, a longitudinal panel survey study, responded to questions on alcohol use and influencing factors, and were followed annually over a 3-year period from 2002 to 2004 (98% retention rate). State-representative, community student samples were recruited in grade 7 in Washington State, United States (US, n = 961, 78% of those eligible; Mage = 13.09, SD = .44) and Victoria, Australia (n = 984, 76% of those eligible; Mage = 12.93, SD = .41). Analyses were conducted using multiple-group structural equation modeling. In both states, early age alcohol use (age 13) had a small but statistically significant association with subsequent alcohol problems (age 15). Overall, there was little evidence for mediation of early alcohol effects. Low self-regulation prospectively predicted peer deviance, alcohol use, and alcohol problems in both states. Peer deviance was more positively related to alcohol use and low self-regulation among students in Victoria compared to students in Washington State. The small but persistent association of early age alcohol use with alcohol problems across both samples is consistent with efforts to delay alcohol initiation to help prevent problematic alcohol use. Self-regulation was an important influence, supporting the need to further investigate the developmental contribution of neurobehavioral disinhibition.

Overweight and obesity in childhood and risk of mental disorder: a 20-year cohort study

OBJECTIVE

Very little is known about whether overweight and obese children have long-term risk for mental health problems. This study examined the association between overweight and obesity in childhood and DSM-IV mood, anxiety, and substance use disorders in young adulthood.

METHOD

Participants in a national Australian school survey when aged 7-15 years in 1985 were re-interviewed 20 years later as young adults aged 26-36 years (1135 women, 1108 men). Body mass index (BMI) was calculated from measured height and weight in childhood and adulthood. Children were classified as overweight or obese based on a BMI ≥85th centile for age and sex-specific height and weight. Obesity in adulthood was defined as BMI of ≥30. Twelve-month DSM-IV diagnoses of mood, anxiety and substance use disorders were obtained from the Composite International Diagnostic Interview. The relative risk (RR) for each class of mental disorder was estimated for childhood overweight/obesity versus non-overweight, and for four weight trajectories: non-overweight in childhood and non-obese in adulthood; overweight in childhood and non-obese in adulthood; non-overweight in childhood and obese in adulthood; and overweight in childhood and obese in adulthood.

RESULTS

Childhood overweight and obesity was associated with an increased risk of mood disorder in adulthood (RR = 1.54, 95%CI 1.06-2.23, p = 0.03), with a similar risk observed among girls and boys. When weight in adulthood was taken into consideration, increased risk of mood disorder was observed only among overweight girls who were obese in adulthood (adjusted RR = 2.03, 95%CI 1.22-3.66, p = 0.006), with childhood overweight or obesity in non-obese adults not associated with any mental disorder.

CONCLUSIONS

Childhood overweight may increase risk for mood disorder in adulthood, especially among overweight girls who become obese women. These results suggest that prevention of childhood overweight is equally important in both sexes for reducing risk of diagnosed mood disorder in adulthood.

50-year mortality trends in children and young people: a study of 50 low-income, middle-income, and high-income countries

BACKGROUND

Global attention has focused on mortality in children younger than 5 years. We analysed global mortality data for people aged 1-24 years across a 50-year period.

METHODS

The WHO mortality database was used to obtain mortality data from 1955 to 2004, by age-group (1-4, 5-9, 10-14, 15-19, and 20-24 years) and stratified by sex. To analyse change in mortality, we calculated mortality rates averaged over three 5-year periods (1955-59, 1978-82, and 2000-04) to investigate trends in deaths caused by communicable and non-communicable diseases and injury.

FINDINGS

Data were available for 50 countries (ten high income, 22 middle income, eight low income, seven very low income, and three unclassified), grouped as Organisation for Economic Co-operation and Development (OECD) countries, Central and South American countries, eastern European countries and ex-Soviet states, and other countries. In 1955, mortality was highest in the 1-4-year age-group. Across the study period, all-cause mortality reduced by 85-93% in children aged 1-4 years, 80-87% in children aged 5-9 years, and 68-78% in young people aged 10-14 years in OECD, Central and South American, and other countries. Smaller declines (41-48%) were recorded in young men (15-24 years), and by 2000-04, mortality in this group was two-to-three times higher than that in young boys (1-4 years). Mortality in young women (15-24 years) was equal to that of young girls (1-4 years) from 2000 onwards. Substantial declines in death caused by communicable diseases were seen in all age-groups and regions, although communicable and non-communicable diseases remained the main causes of death in children (1-9 years) and young women (10-24 years). Injury was the dominant cause of death in young men (10-24 years) in all regions by the late 1970s.

INTERPRETATION

Adolescents and young adults have benefited from the epidemiological transition less than children have, with a reversal of traditional mortality patterns over the past 50 years. Future global health targets should include a focus on the health problems of people aged 10-24 years.

FUNDING

None.

Overweight and obesity between adolescence and young adulthood: a 10-year prospective cohort study

OBJECTIVES

To assess changes in overweight and obesity between adolescence and young adulthood.

DESIGN

Prospective 8-wave cohort study in Victoria, Australia, with 1,520 adolescents tracked from the age of 14 for a period of 10 years.

MAIN OUTCOME MEASURES

Participants aged <18 years were classified as non-overweight, overweight, or obese according to International Obesity Taskforce cutoff points. In those aged >18 years overweight was defined as a body mass index (BMI) ≥ 25; and obesity as a BMI ≥ 30.

RESULTS

The proportion of overweight individuals increased from 20% in mid-adolescence to 33% at the age of 24 years. Obesity increased from 3.6% to 6.7%. Approximately 40% of young adults with a BMI ≥ 25 had been persistently at normal weights during adolescence and approximately 80% had been at a normal weight at some point. Around half of obese young adults had never been classified as obese as adolescents. No individual with persistent obesity in adolescence had a BMI <25 at 24 years. A total of 31% of females and 59% of males who had been overweight for only one or two waves of adolescent data collection had a BMI ≥ 25 at 24 years.

CONCLUSIONS

Substantial shifts in overweight and obesity occur between adolescence and young adulthood; the extent of continuity depends on both the severity and persistence of adiposity in adolescence. Few adolescents who peak into obesity or are persistently overweight achieve a normal weight in young adulthood. Resolution is more common in those who are less persistently overweight as teenagers, suggesting scope for lifestyle interventions in this subgroup.

A prospective study of the effects of optimism on adolescent health risks

CONTEXT

The promotion of optimism has been widely advocated for children and adolescents, but epidemiologic data to support this approach are scant.

METHODS

This was a 3-wave longitudinal study of health and social development in younger adolescents from 3 Australian states. The 5634 student participants, initially aged 12 to 14 years, were assessed for optimistic thinking style, emotional problems, substance use, and antisocial behaviors.

RESULTS

Cross-sectional associations between optimism and each of the study outcomes were strongly protective but tended to differ according to gender in extent. In prospective analyses of the onset of new cases of each study outcome, protective associations were weaker. Those in the highest optimism quartile had risks for depressive symptoms that were reduced by almost half (odds ratio: 0.54 [95% confidence interval: 0.42-0.70]) compared with those in the lowest category. No effect was seen in prevention of anxiety symptoms after adjustment for other aspects of psychological style. In predicting the onset of heavy substance use and antisocial behavior, high optimism had modest protective effects.

CONCLUSIONS

Optimistic thinking style is somewhat protective against adolescent health risks; the clearest effects are seen against depressive symptoms. Promoting optimism along with other aspects of psychological and emotional style has a role in mental health promotion that is likely to be enhanced if an intervention also addresses risk and protective factors in an adolescent's social context.

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.

Pilot multimethod trial of a school-ethos intervention to reduce substance use: building hypotheses about upstream pathways to prevention

PURPOSE

Interventions to improve school ethos can reduce substance use but "upstream" causal pathways relating to implementation and school-level changes are uncertain. We use qualitative and quantitative data from a pilot trial to build hypotheses regarding these.

METHODS

The Healthy School Ethos intervention involved two schools being provided with facilitation, training, and funding to plan and implement actions (some mandatory and some locally determined) to improve school ethos over one year. The evaluation involved a pilot-trial with two intervention and two comparison schools; semi-structured interviews with facilitators, staff, and students; and baseline and follow-up surveys with students aged 11 to 12 years.

RESULTS

Student accounts linked participation in planning or delivering intervention activities with improved self-regard and relationships with staff and other students. Some activities such as re-writing school rules involved broad participation. Students in receipt of actions such as peer-mediation or motivational sessions reported benefits such as improved safety and relationships. Some student accounts linked improved self-regard and relationships with increased engagement and aspirations, and reduced substance use. At 9-month follow-up, students in intervention schools reported less hurting and teasing of others and feeling unsafe at school. Other outcomes suggested intervention benefits but were not significant.

CONCLUSIONS

School-ethos interventions may reduce substance use through upstream pathways involving the aforementioned factors. Future phase-III trials should quantitatively model the extent to which these mediate intervention effects.

Mapping a global agenda for adolescent health

Major changes in health are underway in many low- and middle-income countries that are likely to bring greater focus on adolescents. This commentary, based on a 2009 London meeting, considers the need for strategic information for future global initiatives in adolescent health. Current coverage of adolescent health in global data collections is patchy. There is both the need and scope to extend existing collections into the adolescent years as well as achieve greater harmonization of measures between surveys. The development of a core set of global adolescent health indicators would aid this process. Other important tasks include adapting and testing interventions in low- and middle-income countries, growing research capacity in those settings, better communication of research from those countries, and building structures to implement future global initiatives. A global agenda needs more than good data, but sound information about adolescent health and its social and environmental determinants, will be important in both advocacy and practice.

Association of adolescent symptoms of depression and anxiety with daily smoking and nicotine dependence in young adulthood: findings from a 10-year longitudinal study

AIMS

To examine the association of adolescent depression and anxiety symptoms with daily smoking and nicotine dependence in young adulthood.

DESIGN

A prospective cohort study of adolescent and young adult health (n = 1943). Teen assessments occurred at 6-monthly intervals, with two follow-up assessments in young adulthood (wave 7, 1998; wave 8, 2001-03).

SETTING

Victoria, Australia. Participants Students who participated at least once during the first six (adolescent) waves of the cohort study.

MEASUREMENTS

Adolescent depression and anxiety symptoms were assessed using the Revised Clinical Interview Schedule (CIS-R). Young adult tobacco use was defined as: daily use (6 or 7 days per week) and dependent use (> or =4 on the Fagerstrom Test for Nicotine Dependence).

FINDINGS

Among adolescent 'less than daily' smokers, those with high levels of depression and anxiety symptoms had an increased risk of reporting nicotine dependence in young adulthood [odds ratio (OR) 3.3, 95% confidence interval (CI) 1.2-9.1] compared to young adults who had low levels of adolescent depression and anxiety symptoms, after adjusting for potential confounding factors. Similarly, in the adjusted model (OR 1.9, 95% CI 1.0-3.4), among adolescent 'daily' smokers, those with high levels of depression and anxiety symptoms had an almost two-fold increase in the odds of reporting nicotine dependence in young adulthood compared to young adults with low levels of adolescent depression and anxiety symptoms.

CONCLUSIONS

Adolescent smokers with depression and anxiety symptoms are at increased risk for nicotine dependence into young adulthood. They warrant vigilance from primary care providers in relation to tobacco use well into adulthood.

Cannabis use and educational achievement: findings from three Australasian cohort studies

BACKGROUND

The associations between age of onset of cannabis use and educational achievement were examined using data from three Australasian cohort studies involving over 6000 participants. The research aims were to compare findings across studies and obtain pooled estimates of association using meta-analytic methods.

METHODS

Data on age of onset of cannabis use (<15, 15-17, never before age 18) and three educational outcomes (high school completion, university enrolment, degree attainment) were common to all studies. Each study also assessed a broad range of confounding factors.

RESULTS

There were significant (p<.001) associations between age of onset of cannabis use and all outcomes such that rates of attainment were highest for those who had not used cannabis by age 18 and lowest for those who first used cannabis before age 15. These findings were evident for each study and for the pooled data, and persisted after control for confounding. There was no consistent trend for cannabis use to have greater effect on the academic achievement of males but there was a significant gender by age of onset interaction for university enrolment. This interaction suggested that cannabis use by males had a greater detrimental effect on university participation than for females. Pooled estimates suggested that early use of cannabis may contribute up to 17% of the rate of failure to obtain the educational milestones of high school completion, university enrolment and degree attainment.

CONCLUSIONS

Findings suggest the presence of a robust association between age of onset of cannabis use and subsequent educational achievement.

Pubertal stage and the prevalence of violence and social/relational aggression

OBJECTIVE

We examined associations between pubertal stage and violent adolescent behavior and social/relational aggression.

METHODS

The International Youth Development Study comprises statewide representative student samples in grades 5, 7, and 9 (N = 5769) in Washington State and Victoria, Australia, drawn as a 2-stage cluster sample in each state. We used a school-administered, self-report student survey to measure previous-year violent behavior (ie, attacking or beating up another person) and social/relational aggression (excluding peers from the group, threatening to spread lies or rumors), as well as risk and protective factors and pubertal development. Cross-sectional data were analyzed.

RESULTS

Compared with early puberty, the odds of violent behavior were approximately threefold higher in midpuberty (odds ratio [OR]: 2.87 [95% confidence interval (CI): 1.81-4.55]) and late puberty (OR: 3.79 [95% CI: 2.25-6.39]) after adjustment for demographic factors. For social/relational aggression, there were weaker overall associations after adjustment, but these associations included an interaction between pubertal stage and age, and stronger associations with pubertal stage at younger age were shown (P = .003; midpuberty OR: 1.78 [95% CI: 1.20-2.63]; late puberty OR: 3.00 [95% CI: 1.95-4.63]). Associations between pubertal stage and violent behavior and social/relational aggression remained after the inclusion of social contextual mediators in the analyses.

CONCLUSIONS

Pubertal stage was associated with higher rates of violent behavior and social/relational aggression, with the latter association seen only at younger ages. Puberty is an important phase at which to implement prevention programs to reduce adolescent violent and antisocial behaviors.

The prevalence of childhood sexual abuse and adolescent unwanted sexual contact among boys and girls living in Victoria, Australia

OBJECTIVES

Childhood sexual abuse (CSA) is associated with both short- and long-term adverse mental and physical health consequences, yet there remains considerable controversy about the prevalence of CSA in the general population. There is also little prospective data on unwanted sexual contact (USC) collected during adolescence.

METHODS

Data from a 10-year cohort study of a nationally representative sample of students aged 14-15 years in Victoria, Australia from 1992 to 2003 was used. CSA prior to age 16 was assessed retrospectively at age 24 years using a 6-item validated questionnaire. USC was assessed prospectively via questionnaire at 3 time points during adolescence. Multiple imputation was used to handle missing data.

RESULTS

One thousand nine hundred forty-three of 2032 eligible adolescents participated in at least one wave of the study. One thousand seven hundred forty-five (812 males and 933 females) provided sufficient information to allow for multiple imputation and inclusion in the main analysis. The prevalence of any CSA was substantially higher among girls [17%, 95% confidence interval (CI): 14-20%] than boys (7%, 95% CI: 3-10%), as was the prevalence of USC reported during adolescence (14%, 95% CI 11-16%, versus 6%, 95% CI: 4-8% respectively).

CONCLUSIONS

These findings highlight the high prevalence of childhood sexual abuse and unwanted sexual contact among girls as well as boys.

PRACTICE IMPLICATIONS

In order to accurately inform early recognition, intervention and education programs for individuals with a history of CSA the frequency of sexual abuse must first be precisely quantified. Developing more standardized approaches will be important in order to improve our understanding of the extent of this problem.

Associations between diet quality and depressed mood in adolescents: results from the Australian Healthy Neighbourhoods Study

OBJECTIVE

Adolescence frequently coincides with the onset of psychiatric illness and depression is commonly observed in adolescents. Recent data suggest a role for diet quality in adult depression. Given the importance of adequate nutrition for brain development, it is of interest to examine whether diet quality is also related to depression in adolescents.

METHODS

The study examined 7114 adolescents, aged 10-14 years, who participated in the Australian Healthy Neighbourhoods Study. Healthy and unhealthy diet quality scores were derived from a dietary questionnaire. The Short Mood and Feelings Questionnaire for adolescents measured depression. Adjustments were made for age, gender, socioeconomic status, parental education, parental work status, family conflict, poor family management, dieting behaviours, body mass index, physical activity, and smoking.

RESULTS

Compared to the lowest category of the healthy diet score, the adjusted odds ratios (95% confidence interval) for symptomatic depression across categories (C) was: C2 = 0.61 (0.45-0.84); C3 = 0.58 (0.43-0.79); C4 = 0.47 (0.35-0.64); and C5 = 0.55 (0.40-0.77). Compared to the lowest quintile, the adjusted odds ratios (95% confidence interval) for symptomatic depression across increasing quintiles of the unhealthy diet score were: Q2 = 1.03 (0.87-1.22); Q3 = 1.22 (1.03-1.44); Q4 = 1.29 (1.12-1.50); and Q5 = 1.79 (1.52-2.11).

CONCLUSIONS

Our results demonstrate an association between diet quality and adolescent depression that exists over and above the influence of socioeconomic, family, and other potential confounding factors.

Outcomes of occasional cannabis use in adolescence: 10-year follow-up study in Victoria, Australia

BACKGROUND

Regular adolescent cannabis use predicts a range of later drug use and psychosocial problems. Little is known about whether occasional cannabis use carries similar risks.

AIMS

To examine associations between occasional cannabis use during adolescence and psychosocial and drug use outcomes in young adulthood; and modification of these associations according to the trajectory of cannabis use between adolescence and age 20 years, and other potential risk factors.

METHOD

A 10-year eight-wave cohort study of a representative sample of 1943 secondary school students followed from 14.9 years to 24 years.

RESULTS

Occasional adolescent cannabis users who continued occasional use into early adulthood had higher risks of later alcohol and tobacco dependence and illicit drug use, as well as being less likely to complete a post-secondary qualification than non-users. Those using cannabis at least weekly either during adolescence or at age 20 were at highest risk of drug use problems in young adulthood. Adjustment for smoking in adolescence reduced the association with later educational achievement, but associations with drug use problems remained.

CONCLUSIONS

Occasional adolescent cannabis use predicts later drug use and educational problems. Partial mediation by tobacco use raises a possibility that differential peer affiliation may play a role.

Early intervention in psychotic disorders: faith before facts?

This paper reviews the literature on early intervention in psychotic disorders, weighs the cons of this approach, and makes suggestions for clinicians and researchers regarding how to interpret and respond to what is still an embryonic evidence-base, notably in terms of any long-term benefits.

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.

Intergenerational educational mobility is associated with cardiovascular disease risk behaviours in a cohort of young Australian adults: The Childhood Determinants of Adult Health (CDAH) Study

BACKGROUND

Although educational disparity has been linked to single risk behaviours, it has not previously been studied as a predictor of overall lifestyle. We examined if current education, parental education or educational mobility between generations was associated with healthy lifestyles in young Australian adults.

METHODS

In 2004-06, participant and parental education (high [bachelor degree or higher], intermediate [vocational training], low [secondary school only]) were assessed. Educational mobility was defined as: stable high (participant and parent in high group), stable intermediate (participant and parent in intermediate group), stable low (participant and parent in low group), downwardly (lower group than parent) and upwardly (higher group than parent) mobile. We derived a lifestyle score from 10 healthy behaviours (BMI, non-smoking, alcohol consumption, leisure time physical activity and six components of diet). Scores >4 indicated a high healthy lifestyle score. We estimated the likelihood of having a high healthy lifestyle score by education (participant and parent) and educational mobility.

RESULTS

Complete data were available for 1973 participants (53% female, age range 26 to 36 years). Those with lower education were less likely to have healthy lifestyles. Parental education was not associated with having a high healthy lifestyle score after adjustment for participant's education. Those who moved upward or downward were as likely to have a high healthy lifestyle score as those in the group they attained.

CONCLUSIONS

We found clear disparities in health behaviour by participant education and intergenerational educational mobility. People attaining a higher level of education than their parents appeared protected from developing an unhealthy lifestyle suggesting that population-wide improvements in education may be important for health.

Patterns of adolescent smoking and later nicotine dependence in young adults: a 10-year prospective study

OBJECTIVES

There is considerable variability in progression from smoking initiation to established smoking. This paper addresses the extent to which different patterns of adolescent smoking, including periods of cessation, predict smoking status in young adults.

STUDY DESIGN

Ten-year, eight-wave prospective cohort study of a state-wide community sample in Victoria, Australia.

METHODS

Participants were 1520 students from 44 secondary schools, initially aged 14 to 15 years. Adolescent smoking and quitting patterns were assessed during Waves 1-6 with self-reported frequency of use and a 7-day retrospective diary. The Fagerstrom Test for Nicotine Dependence (ND) was used to assess ND at the age of 24 years (Wave 8).

RESULTS

The prevalence of ND in young adults was 16.9% for all adolescent smokers, with prevalence rates of 6.8% and 26.7% for adolescent non-daily and daily adolescent smokers, respectively. Maximum smoking levels, onset of daily smoking, duration of smoking, escalation time and duration of cessation during adolescence predicted later ND. Daily smokers who ceased smoking for at least two waves (> or = 12 months) had a level of risk similar to adolescents who had never smoked.

CONCLUSIONS

Quitting smoking as an adolescent substantially alters the risk for later ND. For adolescents who become daily smokers, quitting for 12 months should be the aim in tobacco control and clinical interventions.

Self-harm and risk of motor vehicle crashes among young drivers: findings from the DRIVE Study

BACKGROUND

Some motor vehicle crashes, particularly single-vehicle crashes, may result from intentional self-harm. We conducted a prospective cohort study to assess the risk that intentional self-harm poses for motor vehicle crashes among young drivers.

METHODS

We prospectively linked survey data from newly licensed drivers aged 17-24 years to data on licensing attempts and police-reported motor vehicle crashes during the follow-up period. We investigated the role of recent engagement in self-harm on the risk of a crash. We took into account potential confounders, including number of hours of driving per week, psychological symptoms and substance abuse.

RESULTS

We included 18 871 drivers who participated in the DRIVE Study for whom data on self-harm and motor vehicle crashes were available. The mean follow-up was 2 years. Overall, 1495 drivers had 1 or more crashes during the follow-up period. A total of 871 drivers (4.6%) reported that they had engaged in self-harm in the year before the survey. These drivers were at significantly increased risk of a motor vehicle crash compared with drivers who reported no self-harm (relative risk [RR] 1.42, 95% confidence interval [CI] 1.15-1.76). The risk remained significant, even after adjustment for age, sex, average hours of driving per week, previous crash, psychological distress, duration of sleep, risky driving behaviour, substance use, remoteness of residence and socio-economic status (RR 1.37, 95% CI 1.09-1.72). Most of the drivers who reported self-harm and had a subsequent crash were involved in a multiple-vehicle crash (84.1% [74/88]).

INTERPRETATION

Engagement in self-harm behaviour was an independent risk factor for subsequent motor vehicle crash among young drivers, with most crashes involving multiple vehicles.

Alcohol use and related harms in school students in the USA and Australia

Recognizing there have been few methodologically rigorous cross-national studies of youth alcohol and drug behaviour, state student samples were compared in Australia and the USA. Sampling methods were matched to recruit two independent, state-representative, cross-sectional samples of students in Grades 5, 7 and 9 in Washington State, USA, (n = 2866) and Victoria, Australia (n = 2864) in 2002. Of Washington students in Grade 5 (age 11), 10.3% (95% CI 7.2-14.7) of boys and 5.2% (95% CI 3.4-7.9) of girls reported alcohol use in the past year. Prevalence rates were markedly higher in Victoria (34.2%, 95% CI 28.8-40.1 boys; 21.0%, 95% CI 17.1-25.5 girls). Relative to Washington, the students in Victoria demonstrated a two to three times increased likelihood of reporting substance use (either alcohol, tobacco or illicit drug use), and by Grade 9, experiences of loss-of-control of alcohol use, binge drinking (frequent episodes of five or more alcoholic drinks), and injuries related to alcohol were two to four times higher. The high rates of early age alcohol use in Victoria were associated with frequent, heavy and harmful alcohol use and higher overall exposure to alcohol or other drug use. These findings reveal considerable variation in international rates of both adolescent alcohol misuse and co-occurring drug use and suggest the need for cross-national research to identify policies and practices that contribute to the lower rate of adolescent alcohol and drug use observed in the USA in this study.

Global patterns of mortality in young people: a systematic analysis of population health data

BACKGROUND

Pronounced changes in patterns of health take place in adolescence and young adulthood, but the effects on mortality patterns worldwide have not been reported. We analysed worldwide rates and patterns of mortality between early adolescence and young adulthood.

METHODS

We obtained data from the 2004 Global Burden of Disease Study, and used all-cause mortality estimates developed for the 2006 World Health Report, with adjustments for revisions in death from HIV/AIDS and from war and natural disasters. Data for cause of death were derived from national vital registration when available; for other countries we used sample registration data, verbal autopsy, and disease surveillance data to model causes of death. Worldwide rates and patterns of mortality were investigated by WHO region, income status, and cause in age-groups of 10-14 years, 15-19 years, and 20-24 years.

FINDINGS

2.6 million deaths occurred in people aged 10-24 years in 2004. 2.56 million (97%) of these deaths were in low-income and middle-income countries, and almost two thirds (1.67 million) were in sub-Saharan Africa and southeast Asia. Pronounced rises in mortality rates were recorded from early adolescence (10-14 years) to young adulthood (20-24 years), but reasons varied by region and sex. Maternal conditions were a leading cause of female deaths at 15%. HIV/AIDS and tuberculosis contributed to 11% of deaths. Traffic accidents were the largest cause and accounted for 14% of male and 5% of female deaths. Other prominent causes included violence (12% of male deaths) and suicide (6% of all deaths).

INTERPRETATION

Present global priorities for adolescent health policy, which focus on HIV/AIDS and maternal mortality, are an important but insufficient response to prevent mortality in an age-group in which more than two in five deaths are due to intentional and unintentional injuries.

FUNDING

WHO and National Health and Medical Research Council.

Text message communication in primary care research: a randomized controlled trial

BACKGROUND

Text message communication is increasingly used in clinical practice but rarely in research. Particularly in young people, this method of participation in primary care research appears both feasible and acceptable. However, previous experience shows that text messaging for research may lead to lower response rates. Aim. To test the hypothesis that text message communication in primary care research does not lead to lower response rates compared to a paper-based method.

METHODS

This randomized controlled trial took place in 26 randomly selected practices in Victoria, Australia. Consecutive patients aged 16-24 years attending general practice appointments were recruited as part of a larger study on patients' perspectives. Patients owning a mobile phone were randomized to receive a question about satisfaction with the consultation either by text message or on a card completed before leaving the practice. Logistic regression was used to estimate the effect on the response rate of using text message rather than the card method, adjusting for clustering within practices and for differences in baseline characteristics among participants.

RESULTS

In total, 402 of 409 eligible young people agreed to participate and were randomized to either receive a text message (n = 193) or a card enquiry (n = 209). The response rate was 80.2% [95% confidence interval (CI): 73.3-87.1%] with text message and 85.6% (95% CI: 79.6-91.7%) with the card. The adjusted odds of responding (odds ratio: 0.62; 95% CI: 0.30-1.27) were not significantly lower in the group using text messaging compared to the group using the card response method.

CONCLUSION

These findings offer new perspectives for use of text message communication to gather information from patients in primary care research.

Investigating the utility of mobile phones for collecting data about adolescent alcohol use and related mood, stress and coping behaviours: lessons and recommendations

INTRODUCTION AND AIMS

The trajectory from alcohol use to alcohol use disorders in adolescence is yet to be understood. Momentary sampling may assist in capturing 'real-time' data on young people's alcohol use and associated motivational factors. This paper aims to review the feasibility and usefulness of a mobile phone momentary sampling program to capture data about alcohol use and related behaviours.

DESIGN AND METHODS

Two studies were conducted: a school-based study with 18 Year 9 and 11 students and a clinical study with eight high-risk adolescent drinkers. Participants answered questions about their daily activities, alcohol use, stressors and negative mood four times a day for 1 week using a mobile phone momentary sampling program.

RESULTS

In the school-based study, 61% of participants reported drinking alcohol. On drinking days participants spent less time studying (14% vs. 26%), more time sleeping or resting (35% vs. 12%) and more time hanging out (21% vs. 11%) than on non-drinking days. In the high-risk sample, 88% of participants reported drinking alcohol. On drinking days, these participants spent a greater proportion of their waking time with their boyfriend or girlfriend (19.2% vs. 6%) and generally had higher negative mood than on non-drinking days.

DISCUSSION AND CONCLUSIONS

The current mobiletype program was well suited to capturing data on alcohol use in younger, school-attending adolescents. However, to capture alcohol use in older adolescents who lead less routine lives, it is necessary to make some amendments including targeting particular behaviours and symptoms. Recommendations for future studies are proposed.

A mobile phone program to track young people's experiences of mood, stress and coping. Development and testing of the mobiletype program

BACKGROUND

Research examining adolescent mood, stresses, and coping has tended to use retrospective questionnaires which are affected by recall biases. The aim of this study was to develop, pilot, and evaluate a youth-friendly mobile phone program to monitor, in real-time, young people's everyday experiences of mood, stress, and their coping behaviours.

METHOD AND DESIGN

A momentary sampling program was designed for mobile phones, and ran for 7 days, administering a brief questionnaire four random times each day, capturing information on current activity, mood, responses to negative mood, stresses, alcohol and cannabis use. Eleven high school students reviewed the program in focus groups, and 18 students completed 7 days of monitoring.

RESULTS

Engagement with the mobiletype program was high with 76% of 504 possible entries completed and 94% (17/18) of the participants reporting that the program adequately captured their moods, thoughts, and activities. The mobiletype program captured meaningful and analyzable data on the way young people's moods, stresses, coping strategies, and alcohol and cannabis use, vary both between and within individuals.

CONCLUSIONS

The mobiletype program captured a range of detailed and interesting qualitative and quantitative data about young people's everyday mood, stresses, responses, and general functioning.

Are adolescents who moderate their cannabis use at lower risk of later regular and dependent cannabis use?

AIMS

To examine whether moderation of cannabis use among adolescent cannabis users is associated with reductions in cannabis use frequency and risk of dependence in young adulthood.

DESIGN

Ten-year representative cohort study with six surveys in adolescence (mean age 14.9-17.4 years) and two in young adulthood (mean age 20.7 and 24.1 years).

PARTICIPANTS

Inception cohort of 1943 Victorian secondary school students (96% response rate), with 1520 (78% of adolescent participants) interviewed in the final wave.

MEASUREMENTS

Participants were classified into six groups according to the maximum level of adolescent use and the extent of subsequent moderation in such use: non-users, occasional to abstinence, occasional persisting, weekly to abstinence, weekly to occasional and weekly persisting. Outcome measures were weekly+ cannabis use and DSM-IV cannabis dependence at 20 and 24 years.

FINDINGS

Thirty-one per cent reported cannabis use during adolescence. Most adolescent users had moderated their use: from occasional to abstinence (71% of occasional users), weekly to abstinence or weekly to occasional (28% and 48% of weekly+ users, respectively). By age 24, both occasional use groups were at similar, elevated risk of regular and dependent cannabis use compared to non-users. Weekly+ adolescent users were at greatest risk of these outcomes, although the weekly to abstinence group exhibited lower risk than those in the weekly persisting and weekly to occasional groups, who were at similar risk.

CONCLUSIONS

While many young people have dynamic cannabis use patterns, a pattern of moderating adolescent cannabis

Adolescent cannabis users at 24 years: trajectories to regular weekly use and dependence in young adulthood

AIMS

To examine the association between cannabis use by 18 years and problematic cannabis use at 24 years, considering possible mediating and confounding factors.

DESIGN

Ten-year representative prospective study with data from six time-points in adolescence (mean age 14.9-17.4 years) and two in young adulthood (mean age 20.7 and 24.1 years)

SETTING

Victoria, Australia.

PARTICIPANTS

Inception cohort of 1943 secondary school students (95.6% response rate), with 1520 (78% of adolescent participants) interviewed in the final wave.

MEASUREMENTS

Participants reported frequency of cannabis use for the past 6 months at each time-point in adolescence (age 14-17 years). Cannabis exposure was defined as: maximum frequency of use (occasional, weekly, daily), number of waves of use (1 or 2; 3-6) and first wave of use (early use: first waves 1-3). Young adult (24 years) outcomes were: weekly+ cannabis use and DSM-IV cannabis dependence, referred to collectively as problematic use.

FINDINGS

Of those interviewed at age 24 (wave 8), 34% had reported cannabis use in adolescence (waves 1-6), 12% at a level of weekly or more frequent use; 37% of these adolescent cannabis users were using at least weekly at wave 8, with 20% exhibiting dependence. Persistent adolescent cannabis and tobacco use as well as persistent mental health problems were associated strongly with problematic cannabis use at 24 years, after adjustment for potential confounding factors.

CONCLUSIONS

Heavy, persistent and early-onset cannabis use were all strongly predictive of later cannabis problems. Even so, occasional use was not free of later problems. Where there was co-occurring tobacco use or persistent mental health problems, risks for later problem cannabis use was higher.