Helena Romaniuk

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.

The prognosis of common mental disorders in adolescents: a 14-year prospective cohort study

BACKGROUND Most adults with common mental disorders report their first symptoms before 24 years of age. Although adolescent anxiety and depression are frequent, little clarity exists about which syndromes persist into adulthood or resolve before then. In this report, we aim to describe the patterns and predictors of persistence into adulthood. METHODS We recruited a stratified, random sample of 1943 adolescents from 44 secondary schools across the state of Victoria, Australia. Between August, 1992, and January, 2008, we assessed common mental disorder at five points in adolescence and three in young adulthood, commencing at a mean age of 15.5 years and ending at a mean age of 29.1 years. Adolescent disorders were defined on the Revised Clinical Interview Schedule (CIS-R) at five adolescent measurement points, with a primary cutoff score of 12 or higher representing a level at which a family doctor would be concerned. Secondary analyses addressed more severe disorders at a cutoff of 18 or higher. FINDINGS 236 of 821 (29%; 95% CI 25-32) male participants and 498 of 929 (54%; 51-57) female participants reported high symptoms on the CIS-R (≥12) at least once during adolescence. Almost 60% (434/734) went on to report a further episode as a young adult. However, for adolescents with one episode of less than 6 months duration, just over half had no further common mental health disorder as a young adult. Longer duration of mental health disorders in adolescence was the strongest predictor of clear-cut young adult disorder (odds ratio [OR] for persistent young adult disorder vs none 3.16, 95% CI 1.86-5.37). Girls (2.12, 1.29-3.48) and adolescents with a background of parental separation or divorce (1.62, 1.03-2.53) also had a greater likelihood of having ongoing disorder into young adulthood than did those without such a background. Rates of adolescent onset disorder dropped sharply by the late 20s (0.57, 0.45-0.73), suggesting a further resolution for many patients whose symptoms had persisted into the early 20s. INTERPRETATION Episodes of adolescent mental disorder often precede mental disorders in young adults. However, many such disorders, especially when brief in duration, are limited to the teenage years, with further symptom remission common in the late 20s. The resolution of many adolescent disorders gives reason for optimism that interventions that shorten the duration of episodes could prevent much morbidity later in life. FUNDING Australias National Health and Medical Research Council.

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.

Modifiable Determinants of Youth Violence in Australia and the United States: A Longitudinal Study

Abstract Youth violence is a global problem. Few studies have examined whether the prevalence or predictors of youth violence are similar in comparable Western countries like Australia and the United States (US). In the current article, analyses are conducted using two waves of data collected as part of a longitudinal study of adolescent development in approximately 4,000 students aged 12 to 16 years in Victoria, Australia and Washington State, US. Students completed a self-report survey of problem behaviours including violent behaviour, as well as risk and protective factors across five domains (individual, family, peer, school, community). Compared to Washington State, rates of attacking or beating another over the past 12 months were lower in Victoria for females in the first survey and higher for Victorian males in the follow-up survey. Preliminary analyses did not show state-specific predictors of violent behaviour. In the final multivariate analyses of the combined Washington State and Victorian samples, protective factors were being female and student emotion control. Risk factors were prior violent behaviour, family conflict, association with violent peers, community disorganisation, community normsfavourable to drug use, school suspensions and arrests. Given the similarity of influential factors in North America and Australia, application of US early intervention and prevention programs may be warranted, with some tailoring to the Australian context.

Cannabis and progression to other substance use in young adults: findings from a 13-year prospective population-based study

Background Adolescent cannabis use predicts the onset of later illicit drug use. In contrast, little is known about whether cannabis in young adulthood also predicts subsequent progression or cessation of licit or illicit drug use. Methods 13-year longitudinal cohort study with recruitment in secondary school students in Victoria, Australia. There were six waves of adolescent data collection (mean age 14.9–17.4 years) followed by three in young adulthood (mean age 20.7, 24.1 and 29.0 years). Discrete-time proportional hazards models were used to assess predictive associations between cannabis use frequency (occasional (<weekly), weekly to less than daily and daily) in 1756 participants in earlier young adult waves and subsequent cigarette smoking, high-risk alcohol use and amphetamine, ecstasy and cocaine use, including incident use (uptake) and cessation in later young adult waves. Results Compared with continuing occasional cannabis use: (1) never use provided the strongest protection from uptake of all drugs; (2) quitting cannabis lowered rates of illicit drug use uptake; (3) weekly+cannabis users had two to three times the rates of illicit drug use uptake, while daily users had six times the rate of uptake of cigarette smoking; and (4) never use of cannabis was associated with higher rates of cessation from licit drug use, while daily cannabis predicted lower cessation rates for all drugs except cocaine. Conclusions This study provides compelling evidence of the continuing association between cannabis, licit and other illicit drug use well into young adulthood. Preventing cannabis use uptake and use escalation remain crucial health aims given the burden associated with cigarette, alcohol and illicit drug use.

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 adolescents social context.

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.

Prediction of perinatal depression from adolescence and before conception (VIHCS): 20-year prospective cohort study

BACKGROUND Perinatal depression is a neglected global health priority, affecting 10-15% of women in high-income countries and a greater proportion in low-income countries. Outcomes for children include cognitive, behavioural, and emotional difficulties and, in low-income settings, perinatal depression is associated with stunting and physical illness. In the Victorian Intergenerational Health Cohort Study (VIHCS), we aimed to assess the extent to which women with perinatal depressive symptoms had a history of mental health problems before conception. METHODS VIHCS is a follow-up study of participants in the Victorian Adolescent Health Cohort Study (VAHCS), which was initiated in August, 1992, in the state of Victoria, Australia. In VAHCS, participants were assessed for health outcomes at nine timepoints (waves) from age 14 years to age 29 years. Depressive symptoms were measured with the Revised Clinical Interview Schedule and the General Health Questionnaire. Enrolment to VIHCS began in September, 2006, during the ninth wave of VAHCS; depressive symptoms at this timepoint were measured with the Composite International Diagnostic Interview. We contacted women every 6 months (from age 29 years to age 35 years) to identify any pregnancies. We assessed perinatal depressive symptoms with the Edinburgh Postnatal Depression Scale (EPDS) by computer-assisted telephone interview at 32 weeks of gestation, 8 weeks after birth, and 12 months after birth. We defined perinatal depression as an EPDS score of 10 or more. FINDINGS From a stratified random sample of 1000 female participants in VAHCS, we enrolled 384 women with 564 pregnancies. 253 (66%) of these women had a previous history of mental health problems at some point in adolescence or young adulthood. 117 women with a history of mental health problems in both adolescence and young adulthood had 168 pregnancies, and perinatal depressive symptoms were reported for 57 (34%) of these pregnancies, compared with 16 (8%) of 201 pregnancies in 131 women with no preconception history of mental health problems (adjusted odds ratio 8·36, 95% CI 3·34-20·87). Perinatal depressive symptoms were reported at one or more assessment points in 109 pregnancies; a preconception history of mental health problems was reported in 93 (85%) of these pregnancies. INTERPRETATION Perinatal depressive symptoms are mostly preceded by mental health problems that begin before pregnancy, in adolescence or young adulthood. Women with a history of persisting common mental disorders before pregnancy are an identifiable high-risk group, deserving of clinical support throughout the childbearing years. Furthermore, the window for considering preventive intervention for perinatal depression should extend to the time before conception. FUNDING National Health and Medical Research Council (Australia), Victorian Health Promotion Foundation, Colonial Foundation, Australian Rotary Health Research and Perpetual Trustees.

The persistence of adolescent binge drinking into adulthood: Findings from a 15-year prospective cohort study

Objectives To examine the prevalence of binge drinking in adolescence and its persistence into adulthood in an Australian cohort. Design 15-year prospective cohort study. Setting Victoria, Australia. Participants 1943 adolescents were recruited from secondary schools at age 14–15 years. Primary outcome measures Levels of past-week ‘binge’ drinking (5+ standard drinks on a day, each 10 g alcohol) and ‘heavy binge’ drinking (20+ standard drinks on a day for males, 11+ for females) were assessed during six adolescent waves, and across three adult waves up to age 29 years. Results Half of the males (52%) and a third of the females (34%) reported past-week adolescent binge drinking. 90% of male and 70% of female adolescent-onset binge drinkers continued to binge in young adulthood; 70% of males and 48% of females who were not adolescent-onset binge drinkers reported young adult binge drinking. Past-week heavy bingeing was less common in adolescence than adulthood. Overall, 35% of the sample (95% CI 33% to 38%) reported past-week binge drinking in adolescence and young adulthood and one-third (33%; 30% to 35%) first reported binge drinking in young adulthood; only 7% of the sample (6–8%) had binge drinking in adolescence but not young adulthood. ‘Heavy binge’ drinking occurred in adolescence and young adulthood for 9% (8% to 10%); 8% (7% to 10%) reported it in adolescence but no longer in young adulthood; and 24% (22% to 26%) began ‘heavy binge’ drinking in young adulthood. Among adolescent binge drinkers (n=821), young adult binge and heavy binge drinking were predicted by being male, adolescent antisocial behaviour and adverse consequences of drinking in adolescence. Conclusions Binge alcohol use is common and persistent among young Australians. Efforts to prevent the onset of binge drinking during adolescence may substantially reduce harmful patterns of alcohol use in young adulthood.

Comparison of methods for imputing limited-range variables: a simulation study

BackgroundMultiple imputation (MI) was developed as a method to enable valid inferences to be obtained in the presence of missing data rather than to re-create the missing values. Within the applied setting, it remains unclear how important it is that imputed values should be plausible for individual observations. One variable type for which MI may lead to implausible values is a limited-range variable, where imputed values may fall outside the observable range. The aim of this work was to compare methods for imputing limited-range variables, with a focus on those that restrict the range of the imputed values.MethodsUsing data from a study of adolescent health, we consider three variables based on responses to the General Health Questionnaire (GHQ), a tool for detecting minor psychiatric illness. These variables, based on different scoring methods for the GHQ, resulted in three continuous distributions with mild, moderate and severe positive skewness. In an otherwise complete dataset, we set 33% of the GHQ observations to missing completely at random or missing at random; repeating this process to create 1000 datasets with incomplete data for each scenario.For each dataset, we imputed values on the raw scale and following a zero-skewness log transformation using: univariate regression with no rounding; post-imputation rounding; truncated normal regression; and predictive mean matching. We estimated the marginal mean of the GHQ and the association between the GHQ and a fully observed binary outcome, comparing the results with complete data statistics.ResultsImputation with no rounding performed well when applied to data on the raw scale. Post-imputation rounding and imputation using truncated normal regression produced higher marginal means than the complete data estimate when data had a moderate or severe skew, and this was associated with under-coverage of the complete data estimate. Predictive mean matching also produced under-coverage of the complete data estimate. For the estimate of association, all methods produced similar estimates to the complete data.ConclusionsFor data with a limited range, multiple imputation using techniques that restrict the range of imputed values can result in biased estimates for the marginal mean when data are highly skewed.