Childhood social disadvantage and smoking in adulthood: results of a 25-year longitudinal study

AIM: To examine the associations between exposure to socio-economic disadvantage in childhood and smoking in adulthood. DESIGN: A 25-year longitudinal study of the health, development and adjustment of a birth cohort of 1265 New Zealand children. MEASUREMENTS: Assessments of childhood socio-economic disadvantage, smoking in adulthood and potential mediating pathways, including: parental education, family socio-economic status, family living standards and family income; smoking frequency and nicotine dependence at age 25 years; child IQ, educational achievement by age 18 years, conduct problems ages 14-16 years, parental smoking 0-16 years and peer smoking at 16 years. FINDINGS: Smoking at age 25 was correlated significantly (P < 0.0001) with increasing childhood socio-economic disadvantage. Further, indicators of childhood socio-economic disadvantage were correlated significantly (P < 0.0001) with the intervening variables of childhood intelligence, school achievement, conduct problems and exposure to parental and peer smoking; which in turn were correlated significantly (P < 0.0001) with measures of smoking at age 25. Structural equation modelling suggested that the linkages between the latent factor of childhood disadvantage and later smoking were explained largely by a series of pathways involving cognitive/educational factors, adolescent behavioural adjustment and exposure to parental and peer smoking. CONCLUSIONS: The current study suggested that smoking in adulthood is influenced by childhood socio-economic disadvantage via the mediating pathways of cognitive/educational factors, adolescent behaviour and parental and peer smoking.     

Consequences of youth tobacco use: a review of prospective behavioural studies

BACKGROUND: Cigarette smoking represents a significant health problem and tobacco has been identified as causing more preventable diseases and premature deaths than any other drug. Although health consequences from smoking have been documented, there has been a surprising lack of research into behavioural consequences. AIMS: To review what is known of the long-term relationship between patterns of tobacco use prior to age 18 years and behavioural consequences in adulthood. METHOD: A literature search of electronic abstraction services from 1980 to September 2005 was conducted. To be included in the review, studies had to have large, representative samples, be longitudinal studies with baseline age under 18 years and follow-up age 18 years or older and clarify effects due to attrition, leaving 16 articles that met the inclusion criteria. Two reviewers evaluated each paper. FINDINGS: Adolescent tobacco use predicts a range of early adult social and health problems. Surprisingly few studies met the inclusion criteria. The limited evidence available suggests that adolescent tobacco smoking increases the likelihood of early adult tobacco use and the initiation of alcohol use or the development of alcohol-related problems. The link between adolescent tobacco use and subsequent cannabis use was not resolved convincingly from the studies summarized. The effects of tobacco use on later illicit drug use tended to fall away when adjusting for underlying risk factors. Existing studies of the effects of tobacco use on later mental health have many limitations. Nevertheless, a finding that youth tobacco use may predict subsequent mental health problems deserves further investigation. The possible effects of tobacco use on academic/social problems and sleep problems also warrant further investigation. CONCLUSION: This review highlights links between youth tobacco use and subsequent behavioural and mental health problems. It provides health care professionals with evidence of the possible harmful effects of youth tobacco smoking on later social, emotional, and behavioural well-being.     

Is mental health in childhood a major predictor of smoking in adolescence?

Aims. To test an extended version of Pomerleau's (1997) hypothesis that children with mental health problems are at higher risk of smoking in preadolescence and adolescence. Design. Information concerning mental health from 5 to 13 years, smoking at ages 11 and 15, and family disadvantage at age 7 was available for 773 children enrolled in a longitudinal study of children and adolescents. Participants. Participants were enrolled into the Dunedin Multidisciplinary Health and Development Study, which is a longitudinal investigation of the health, development and behaviour of a large group of New Zealand children born between 1 April 1972 and 31 March 1973. Measurements. Assessment of mental health problems in childhood was based upon parent and teacher reports of behavioural and emotional problems. In pre-adolescence, mental health was assessed by self, parent and teacher report. Smoking was assessed by self-report. Findings. None of the potential risk factors of gender, childhood disadvantage or childhood mental health problems predicted onset of smoking in pre-adolescence. Daily smoking at age 15 was best predicted by smoking in preadolescence, being female and experiencing childhood disadvantage. Pre-adolescent mental health was only weakly predictive of later smoking and this association appeared to be confounded with background disadvantage. Conclusions. We found little support for the extension of Pomerleau's (1997) hypothesis to childhood mental health. Our findings also run counter to recent suggestions for targeting smoking prevention at groups of children with mental health disorders.     

Childhood and adolescent psychopathology and subsequent tobacco smoking in young adults: findings from an Australian birth cohort

Aims To examine whether child and adolescent psychopathology predicts subsequent tobacco use at 14 and 21 years of age. Design Prospective birth cohort study. Setting Data are taken from the Mater Misericordiae Hospital and University of Queensland Study of Pregnancy and its outcomes (MUSP), a prospective longitudinal study which recruited women at their first antenatal visit in Brisbane, Australia. Participants A 5‐, 14‐ and 21‐year follow‐up of children whose mother's were recruited into the MUSP birth cohort study at their first antenatal visit. Measurements Psychopathology exposure was measured using the Achenbach's Child Behaviour Checklist (CBCL) at 5 years, the Youth Self Report (YSR) at 14 years and the Young Adult Self Report (YASR) at 21 years. Outcome measures were the children's tobacco smoking status at the 14 and 21 years' follow‐up and the Composite International Diagnostic Interview (CIDI) based DSM‐IV nicotine dependence at 21 years' follow‐up. Findings Externalizing symptoms had the strongest association with subsequent tobacco use. Children who met the criteria for CBCL aggression at 5 years were more likely to be tobacco smokers at the 14‐year follow‐up. YSR externalizing behaviours at the 14‐year follow‐up predicted tobacco smoking, but not DSM‐IV nicotine dependence at the 21‐year follow‐up. Internalizing behaviour (anxiety/depression) was associated with a reduced rate of smoking at the 14‐ and 21‐year follow‐ups, but externalizing behaviour and attention problems at 14 and 21 years were associated separately and cumulatively with nicotine dependence at the 21‐year follow‐up. Conclusion Childhood and adolescent psychopathology predict tobacco smoking, but some forms of psychopathology predict increased (aggression/delinquency; attention problems) and other forms decreased (anxiety/depression) smoking. There may be some benefits in targeting children with early onset aggressive/delinquent behaviour problems with tobacco smoking prevention initiatives.     

Peer Environment Mediates Parental History and Individual Risk in the Etiology of Cannabis Use Disorder in Boys: A 10-Year Prospective Study

Previous research has shown that a trait termed neurobehavior disinhibition (ND) measured in childhood predicts substance use disorder by young adulthood. The present investigation extends these findings by determining the degree to which peer environment mediates the association between ND and development of cannabis use disorder (CUD). ND was measured in a sample of 216 boys 10–12 years of age. The peer environment was assessed at age 16. Current CUD was determined at age 22. Paternal and maternal SUD predicted son's ND which, in turn, predicted son's peer environment and, subsequently, son's cannabis use frequency and CUD. Peer environment mediated the association between ND and cannabis use and ND and CUD. Maternal and paternal SUD predicted the peer environment. Parental SUD, son's ND, and son's peer environment predicted CUD at age 22 with 84% accuracy.     

Adolescent alcohol and tobacco use: onset,persistence and trajectories of use across two samples

Aims We examined the alcohol‐tobacco relationship using two prospective, ethnically diverse samples. Trajectories of alcohol and tobacco use are portrayed overall and by sex and ethnicity. Using prospective analyses, we examine directional influences between alcohol and tobacco use, and we characterize initiation versus persistence of drinking and smoking as a function of use of the other substance. Design, setting Data were from the National Longitudinal Study of Adolescent Health (AddHealth) and the Adolescent Health Risk Study (AHRS). Follow‐up intervals for AddHealth and AHRS were 1 and 5 years, respectively. Participants AddHealth respondents (n = 4831) were on average 14.8 years old (48% male, 23% black, 61% white) and AHRS respondents (n = 1814) were on average 16.7 years old (47% male, 44% black, 49% white). Measurements Two alcohol consumption variables and two smoking variables were used: drinking frequency and heavy drinking frequency, and regular (current) smoking and daily number of cigarettes. Findings Alcohol and tobacco use exhibited monotonic increases over adolescence and young adulthood. Men and white respondents reported more use than women and black respondents. Alcohol and tobacco were moderately associated at both times. Analyses revealed that prior alcohol use predicted tobacco use more strongly than the converse. Initiation of smoking was a function of prior drinking; to a lesser extent, initiation of drinking was a function of prior smoking. Persistence of smoking was a function of prior drinking and persistence of drinking was a function of prior smoking. Conclusions Provisional support exists for the claim that alcohol use predicts tobacco use more strongly than the converse. For both drinking and smoking, onset and persistence are predicted by prior use of the other substance, and these associations were robust across sex and ethnicity.     

Predictors of age at onset of tobacco and cannabis use in Danish adolescents

Introduction: Early onset of tobacco and cannabis use predicts later substance abuse and risk behaviour and has large health consequences. Objectives: The aim of this study was to examine risk factors for the age at onset of smoking and cannabis use among a group of Danish children between 7 years and 18 years of age. Methods: Four hundred and eighty randomly selected children and their parents participated in a study about the prevalence of asthma. The study included questions about alcohol, tobacco and cannabis use. The children were interviewed face‐to‐face while the parents answered a questionnaire. Results: The age at onset of daily smoking was significantly associated with the adolescents' tendency to binge drink [hazard ratio 4.78, 95% confidence interval (CI) (1.85–12.34), P = 0.001) and to use hard drugs [hazard ratio 2.81, 95% CI (1.03–7.78), P = 0.047], whereas the age at onset of cannabis use was significantly associated with binge drinking [hazard ratio 3.29, 95% CI (1.51–7.20), P = 0.003] and cigarette smoking [hazard ratio 2.51, 95% CI (1.26–5.00), P = 0.009]. There were no significant effect of the parents' smoking and alcohol habits, their socioeconomic or marital status on the adolescent' age at onset of smoking or cannabis. Conclusion: This study shows a close connection between adolescent tobacco and cannabis use and alcohol habits. Knowledge of this is important when planning future prevention strategies. Please cite this paper as: Wium‐Andersen IK, Wium‐Andersen MK, Becker U and Thomsen SF. Predictors of age at onset of tobacco and cannabis use in Danish adolescents. Clin Respir J 2010; 4: 162–167.     

The effect of parents' alcohol problems on children's behaviour as reported by parents and by teachers

Associations between parents' alcohol problems when children were aged 9 and children's behaviour at ages 9 and 13 as reported by parents and teachers were investigated. The sample consisted of participants in a multidisciplinary longitudinal study, data were collected by face-to-face interview. When compared to children with no or mild parental alcohol problems, children classified as having severe parental alcohol problems were more likely to display high levels of problem behaviour at age 9 as reported by teachers and at age 13 as reported by parents. Poorer family relationships, lower verbal and reading proficiency and being male were also associated with high levels of behaviour problems.     

Medication use,sleep, and caregiver smoking status among urban children with asthma

Objective: Children living in urban settings from low-income, minority families are at a high risk for experiencing asthma morbidity. Environmental tobacco smoke (ETS, i.e., secondhand) exposure, typically from caregiver smoking, has been associated with increased quick-relief medication use and child nocturnal awakenings due to increased asthma symptoms as well as worse sleep quality in children with asthma. This study investigated the moderating role of caregiver smoking status on the association between quick-relief medication use and child's sleep quality in urban children with persistent asthma. Methods: Fifty-four urban children with persistent asthma and their primary caregivers completed a baseline research session. Caregivers then completed ecological momentary assessment surveys via smartphones twice daily for two weeks in which smoking behaviors, child quick-relief medication use, and child's sleep quality were assessed. Results: Twenty caregivers (37%) reported smoking at least one day across the two-week period. The caregiver smoking status significantly moderated the association between quick-relief medication use and child's sleep quality after controlling for child age and monthly household income. The caregiver smoking status exacerbated the association between quick-relief medication use and child's sleep quality, such that more medication usage was associated with worse sleep quality. Conclusions: Findings suggest that in urban families with a caregiver who smokes, more daily quick-relief medication use may put children at an increased risk for worse sleep quality. The effects of ETS exposure on child's sleep quality in addition to child asthma symptoms should be an integral part of discussions between pediatric healthcare providers and families of children with asthma.     

Tobacco use in local authority children's homes: a socioecological exploration of influences

BackgroundResearch on tobacco use among looked-after children (LAC) has primarily focused on the individual characteristics of young people in care. We aimed to conceptualise additional factors influencing tobacco use by young people living in English local authority children's homes from a policy and provider perspective.MethodsWe did a socioecological analysis of existing data, which included an evaluation of LAC health assessment documentation (n=31 cases), a survey of residential carers in six local authorities in the East Midlands (n=42 respondents), and semi-structured interviews with residential carers (n=14) working in three children's homes operated by one local authority in the East Midlands. We thematically coded and mapped these data to the social ecological model for health promotion to identify and understand the interplay of influences on tobacco use. Collaborative consensus was reached on coding and interpretation. We chose the social ecological model for its potential to answer questions about how to address tobacco use and highlight potential leverage points.Findings32 factors influencing tobacco use were identified: intrapersonal level (n=10), interpersonal level (n=9), institutional level (n=6), community level (n=3), and macro-organisational (policy) level (n=4). The challenge of balancing child protection responsibilities and safeguarding, with expected parenting practices were highlighted. Institutional, organisational, and community strategies were found to facilitate tobacco use. For example, provision of designated smoking areas in the grounds of the homes and the ease at which young people can purchase tobacco in the local area were compounded by the scarcity of policy monitoring and information sharing at the macro-organisational level. Some data fell outside of individual chose the social ecological model levels, requiring a degree of researcher interpretation.InterpretationVarious influences across and within multiple levels of the care system might complicate and compound typical youth smoking influences and measures to address them. We recommend that, in the development of smoke-free children's home policies, local authorities should be guided by the experiences and knowledge of carers and be cognisant of previous implementation challenges or successes to enable informed and contextually relevant strategies to be developed and implemented. This study offers a much-needed direction for developing and testing tobacco-related interventions targeting this vulnerable population.FundingUniversity of Nottingham PhD studentship and the UK Centre for Tobacco and Alcohol Studies.     

Children's Attitudes to Alcohol and Awareness of Alcohol-Related Problems*

An interview study of 8–9-year-old New Zealand children and their mothers revealed considerable consistency in reports of the children's experience with alcohol. The majority had tried alcohol and a quarter had at least a sip or drink in a typical month. The context of use was a parental one for the majority of children. Two-thirds of their fathers and 40% of their mothers had at least one drink in a typical week and there was a small positive relationship between parents' use and the frequency of the child's alcohol use. The children's attitudes towards alcohol were assessed using the Jahoda Judgement of Photographs Task and despite their personal use of alcohol the majority of children demonstrated negative attitudes to alcohol. This was particularly marked among the half of the children who were aware of an alcohol-related problem in their immediate social environment. Among the other half of the children, unaware of any alcohol-related problems, there was a tendency for the children of parents who drank more to have more positive attitudes.     

A longitudinal study of cannabis use and mental health from adolescence to early adulthood

Aims. To examine the longitudinal association between cannabis use and mental health. Design. Information concerning cannabis use and mental health from 15 to 21 years was available for a large sample of individuals as part of a longitudinal study from childhood to adulthood. Participants. Participants were enrolled in the Dunedin Multidisciplinary Health and Development Study, a research programme on the health, development and behaviour of a large group of New Zealanders born between 1 April 1972 and 31 March 1973. Measurements. Cannabis use and identification of mental disorder was based upon self‐report as part of a general assessment of mental health using a standard diagnostic interview. Daily smoking and alcohol use at age 15 were assessed by self‐report. Indices of family socio‐economic status, family climate and parent ‐ child interaction were formed using information gathered from parent report and behavioural observations over early childhood. Childhood behaviour problems were assessed by parent and teacher report. Attachment to parents was assessed in adolescence. Findings. Cross‐sectional associations between cannabis use and mental disorder were significant at all three ages. Both outcome variables shared similar pathways of low socio‐economic status and history of behaviour problems in childhood, and low parental attachment in adolescence. Mental disorder at age 15 led to a small but significantly elevated risk of cannabis use at age 18; by contrast, cannabis use at age 18 elevated the risk of mental disorder at age 21. The latter association reflected the extent to which cannabis dependence and other externalizing disorders at age 21 were predicted by earlier level of involvement with cannabis. Conclusions. The findings suggest that the primary causal direction leads from mental disorder to cannabis use among adolescents and the reverse in early adulthood. Both alcohol use and cigarette smoking had independent associations with later mental health disorder.     

Substance use and common child mental health problems: examining longitudinal associations in a British sample

Aims To examine the longitudinal associations in both directions between mental health and substance use in adolescence. Design Three‐year longitudinal cohort. Setting Britain (nationally representative sample). Participants 3607 youths aged 11–16 years at baseline. Measurements Externalizing and internalizing mental health problems were measured using brief questionnaires (parent‐reported Strengths and Difficulties Questionnaire) and diagnostic interviews, including clinician‐rated diagnoses of mental disorder. Substance use was measured by youth self‐report, and included regular smoking, frequent alcohol consumption, regular cannabis use and ever taking other illicit drugs. Findings Externalizing (specifically behavioural) problems at baseline independently predicted all forms of substance use, with a particularly strong effect on smoking. In all cases this association showed a dose–response relationship. In contrast, although internalizing problems had a strong univariable association with smoking, this disappeared after adjusting for comorbid externalizing problems. There was little or no evidence that baseline substance use predicted mental health at follow‐up. Conclusions Externalizing problems predict adolescent substance use, and adjusting for comorbid externalizing problems is vital when investigating the effects of internalizing problems. A dose–response effect of externalizing problems is seen across the full range. Programmes seeking to prevent adolescent substance use by reducing externalizing problems may therefore wish to consider population‐wide interventions rather than targeting individuals only at the negative extreme.     

Predictors of marijuana use and uptake among teenagers in Sydney, Australia

Information on drug-related behaviors was obtained from a random sample of teenagers aged 14 to 19 years in Sydney, Australia, interviewed in their homes in 1985 (N = 996) and 1986 (N = 756). The 1985 prevalence of current marijuana use was 10%. The predictors of marijuana use were: male sex; heavier, more frequent alcohol use; use of drugs other than alcohol, tobacco, or marijuana; marijuana use by siblings, friends, and other acquaintances; attitudes and beliefs favoring drug use; the attitude that possession of marijuana should not be a criminal offense; and the attitude that marijuana is not an important drug issue. In the 756 reinterviewed respondents, prevalence of marijuana use rose from 7% in 1985 to 9% in 1986. The rate of uptake was 6% and peaked at 12% at age 17. The predictors of uptake were: age; male sex; heavier, more frequent alcohol use; tobacco smoking; attitudes and beliefs favoring drugs use; and the attitude that marijuana smoking should be legal. Strategies to prevent marijuana use need to take into account the strong association between heavy drinking and marijuana use, the influence of drug users in the social network, and attitudes and beliefs about drugs.     

Alcohol use,externalizing problems,and depressive symptoms among American Indian youth: The role of self-efficacy

Background: There is a need to understand resiliency factors which can be used to inform and design interventions to prevent externalizing problems, substance use, and depressive symptoms among American Indian (AI) youth. Objectives: The present study examined the role of self-efficacy in externalizing problems, alcohol use, and depressive symptoms among AI youth from the North American plains. Methods: Participants for this study included 146 (53 boys and 93 girls) adolescents, with an age range of 13–18 (M?=?14.5) years of age. Results: High self-efficacy for resisting negative peer influences predicted both lower rates of alcohol use and fewer externalizing behaviors. Furthermore, higher levels of both academic and social self-efficacy predicted fewer depressive symptoms. The hypothesis that academic self-efficacy would predict depressive symptoms was not supported. Conclusion: As expected, the best-fitting path model showed self-efficacy for resisting negative peer influences predicting both alcohol use and externalizing problems, and social self-efficacy (as well as being female) predicting depressive symptoms among AI youth. Therefore, this study supports the importance of self-efficacy beliefs for alcohol use and externalizing problems, as well as depressive symptoms, among AI youth.     

Early onset cannabis use and psychosocial adjustment in young adults

The relationships between early onset (prior to 16 years) cannabis use and later psychosocial adjustment was examined in a birth cohort of New Zealand children studied to age 18 years. Early onset users had significantly higher rates of later substance use, juvenile offending, mental health problems, unemployment and school dropout. The linkages between early onset cannabis use and later outcomes were largely explained by two routes that linked cannabis use to later adjustment. First, those electing to use cannabis were a high risk population characterized by social disadvantage, childhood adversity, early onset behavioural difficulties and adverse peer affiliations. Secondly, early onset cannabis use was associated with subsequent affiliations with delinquent and substance using peers, moving away from home and dropping out of education with these factors in turn, being associated with increased psychosocial risk. The implications of these results are examined.     

Multiple Risk Factor Model Predicting Cannabis Use and Use Disorders: A Longitudinal Study

Background: Identification of factors associated with the initiation and continuation of cannabis use is important for any preventive work. Objectives: This study aimed to examine the early life course predictors of cannabis use and the development of cannabis use disorder in early adulthood. Methods: Data from Mater Hospital and University of Queensland Study of Pregnancy (MUSP), a population-based prospective birth cohort study. Participants were a cohort of 2,493 young adults who completed the life-time version of the Composite International Diagnostic Interview-computerized version (CIDI-Auto) at the 21-year follow-up, and for whom data were available from previous follow-ups. Ever use and age at first use of cannabis was assessed via self-report, and cannabis use disorder was measured based on Diagnostic and Statistical Manual version IV (DSM-IV) diagnostic criteria. Life course predictors were obtained between the child's birth and the 14-year follow-up. Results: Of 2,493 young adults, 51.4% reported having ever used cannabis, and 21.1% of young adults were classified as having ever had a cannabis use disorder. Child's gender, changes in maternal marital status, maternal smoking, child school performance, childhood sexual abuse, early adolescence smoking and alcohol consumption, and adolescent aggression/delinquency were strongly associated with young adult cannabis use and use disorder. Exposure to multiple risk factors was associated with greater risk of outcomes. Conclusions: There are a number of strong predictors of cannabis use identified in this study. They suggest that the social context within which children are reared has a major influence on cannabis use and use disorders.     

Prospective associations of parental smoking,alcohol use,marital status,maternal satisfaction,and parental and childhood body mass index at 6.5 years with later problematic eating attitudes

Background:

Few studies have prospectively investigated whether early-life exposures are associated with pre-adolescent eating attitudes.

Objective:

The objective of this study is to prospectively investigate associations of parental smoking, alcohol use, marital status, measures of maternal satisfaction, self-reported parental body mass index (BMI) and clinically measured childhood BMI, assessed between birth and 6.5 years, with problematic eating attitudes at 11.5 years.

Methods:

Observational cohort analysis nested within the Promotion of Breastfeeding Intervention Trial, a cluster-randomised trial conducted in 31 maternity hospitals and affiliated polyclinics in Belarus. Our primary outcome was a Children''s Eating Attitudes Test (ChEAT) score ⩾22.5 (85th percentile), an indicator of problematic eating attitudes. We employed multivariable mixed logistic regression models, which allow inference at the individual level. We also performed instrumental variable (IV) analysis using parents'' BMIs as instruments for the child''s BMI, to assess whether associations could be explained by residual confounding or reverse causation.

Subjects:

Of the 17 046 infants enrolled between 1996 and 1997 across Belarus, 13 751 (80.7%) completed the ChEAT test at 11.5 years.

Results:

In fully adjusted models, overweight children at age 6.5 years had a 2.14-fold (95% confidence interval (CI): 1.82, 2.52) increased odds of having ChEAT scores ⩾85th percentile at age 11.5 years, and those who were obese had a 3.89-fold (95% CI: 2.95, 5.14) increased odds compared with normal-weight children. Children of mothers or fathers who were themselves overweight or obese were more likely to score ⩾85th percentile (P for trend ⩽0.001). IV analysis was consistent with a child''s BMI causally affecting future eating attitudes. There was little evidence that parental smoking, alcohol use, or marital status or maternal satisfaction were associated with eating attitudes.

Conclusion:

In our large, prospective cohort in Belarus, both parental and childhood overweight and obesity at 6.5 years were associated with pre-adolescent problematic eating attitudes 5 years later.     

Cannabis use and later life outcomes

AIM: To examine the associations between the extent of cannabis use during adolescence and young adulthood and later education, economic, employment, relationship satisfaction and life satisfaction outcomes. DESIGN: A longitudinal study of a New Zealand birth cohort studied to age 25 years. MEASUREMENTS: Measures of: cannabis use at ages 14-25; university degree attainment to age 25; income at age 25; welfare dependence during the period 21-25 years; unemployment 21-25 years; relationship quality; life satisfaction. Also, measures of childhood socio-economic disadvantage, family adversity, childhood and early adolescent behavioural adjustment and cognitive ability and adolescent and young adult mental health and substance use. FINDINGS: There were statistically significant bivariate associations between increasing levels of cannabis use at ages 14-21 and: lower levels of degree attainment by age 25 (P < 0.0001); lower income at age 25 (P < 0.01); higher levels of welfare dependence (P < 0.0001); higher unemployment (P < 0.0001); lower levels of relationship satisfaction (P < 0.001); and lower levels of life satisfaction (P < 0.0001). These associations were adjusted for a range of potentially confounding factors including: family socio-economic background; family functioning; exposure to child abuse; childhood and adolescent adjustment; early adolescent academic achievement; and comorbid mental disorders and substance use. After adjustment, the associations between increasing cannabis use and all outcome measures remained statistically significant (P < 0.05). CONCLUSIONS: The results of the present study suggest that increasing cannabis use in late adolescence and early adulthood is associated with a range of adverse outcomes in later life. High levels of cannabis use are related to poorer educational outcomes, lower income, greater welfare dependence and unemployment and lower relationship and life satisfaction. The findings add to a growing body of knowledge regarding the adverse consequences of heavy cannabis use.     

Childhood obesity and school absenteeism: a systematic review and meta‐analysis

Regular school attendance is a key determinant of student's academic achievement and psychosocial development. Obesity may affect children's school attendance through its detrimental impact on their physical and mental health. A literature search was conducted in the PubMed, Web of Science and Cochrane Library for articles published until April 2017 that examined the relationship between unhealthy body weight and school absenteeism among children and adolescents. Thirteen studies total (10 cross‐sectional and three longitudinal) conducted in seven countries were identified. The mean and median sample sizes were 24,861 and 3,113, respectively. Ten studies objectively measured children's height and weight, and three were based on parents' self‐report. Four studies measured absenteeism using school administrative data, and nine administered questionnaires on children's parents. Among them, 11 reported a statistically significant positive association between childhood overweight/obesity and school absence, whereas two reported null effect. The meta‐analysis found that the odds of being absent from school was 27% and 54% higher among children with overweight and obesity than among their normal weight counterparts, respectively. Future studies should adopt an experimental study design and accurate measures on school attendance and delineate the underlining pathways linking childhood obesity to school absenteeism through obesity‐related illnesses and psychosocial problems.