Cigarette smoking and age of menopause: a large prospective study.

OBJECTIVES: One of the possible consequences of tobacco consumption is that it contributes to an earlier age of menopause, though the causal relationship is yet to be confirmed. This study aimed to examine the prospective association between smoking and earlier age of menopause in a cohort of middle age Australian women after adjustment for a number of potential confounders. STUDY DESIGN: 21-Year follow-up of a cohort prospective study, Brisbane, Australia. MAIN OUTCOME MEASURES: Age of menopause measured at the 21-year follow-up. Smoking and menopausal status were assessed by self-report. Other covariates were measured prospectively in the previous follow-ups. RESULTS: This study is based on 3545 women who provided data on their menopausal status at the 21-year follow-up of the study, and prospective as well as concurrent data on smoking. In univariate analysis tobacco smoking during the reproductive life course, socio-economic status and gravidity were significantly associated with earlier age of menopause. In multivariate analyses women who smoked cigarettes were more likely to experience earlier menopause than non-smokers. Compared to current smokers, risk of early menopause was significantly lower in those women who quit smoking in the past. CONCLUSIONS: The data suggest that the impact of smoking is independent of other covariates associated with both smoking and age of menopause. The findings raise the possibility that effective quit smoking interventions may lead to a later age of menopause, and reduce the risk of adverse health consequences of early menopause.

Association of breastfeeding and adolescents' psychopathology: a large prospective study.

PURPOSE: There is little known about the association between breastfeeding and long-term child psychopathology. This study aimed to examine the impact of breastfeeding on child mental health and problem behavior at 14 years and whether this association is confounded by other variables. SUBJECTS AND METHODS: Data were from a pre-birth prospective study that included mothers and their children followed up from pregnancy to 14 years of the child's age in Brisbane, Australia. The child's anxiety/depression, withdrawal problems, somatic complaints, social problems, thought problems, attention problems, aggression, and delinquency were measured using the Achenbach Youth Self Report at 14 years. Breastfeeding was prospectively assessed at the 6-month follow-up of the study. The analysis was based on 4,502 adolescents who responded to the YSR questionnaire and for whom prospective data were available on breastfeeding. RESULTS: Breastfeeding as reported by mothers when the child was 6 months old predicted reduced symptoms of child mental health and problem behavior at 14 years. The impact of breastfeeding on the child's social problems, attention problems, and aggressive behavior remained statistically significant after controlling for the effect of other variables, such as unplanned pregnancy, maternal mental health, and substance use during pregnancy. CONCLUSIONS: Our data suggest that breastfeeding for at least 4 months can have a significant protective effect on a child's social, attention, and aggression problems in early adolescence. Given the limitations of the existing evidence, further research is needed to investigate the robustness of the findings of this study and the mechanisms of long-term association between breastfeeding and reduced social, attention, and aggression problems of the offspring in adolescence.

Young adults' gambling and its association with mental health and substance use problems.

OBJECTIVE: To examine the socio-demographic characteristics of young adults' gambling and its association with mental health and substance use behaviour. METHODS: The study is based on 3,512 young adults (1648 males) for whom data from the Mater-University of Queensland Study of Pregnancy (MUSP) were available on self-report gambling, gambling expenditure, Achenbach's Young Adult Self Report and substance use at the 21-year follow-up of the MUSP. The participants' age ranged between 18.2 and 23.6 (mean = 20.6, standard deviation = 0.8) years. RESULTS: Two-fifths of the young adults reported gambling. Males reported more money spent on gambling and were significantly more likely to be at risk of problem gambling. Gambling and problem gambling were significantly more common in less-educated individuals, those who had higher income or those who had a paid job. Individuals who reported gambling were more likely to smoke cigarettes, drink more than a glass of alcohol per day, use illicit drugs, or exhibit high levels of externalising behaviour than non-gamblers. CONCLUSIONS: The findings confirm the high prevalence of gambling and gambling expenditure in young adults. Individuals who are involved in gambling are more likely to report cigarette smoking, alcohol consumption, and use of illicit drugs. There is a need for further research to explore the mechanisms of association between gambling behaviour and individuals' mental health and substance use. IMPLICATIONS: Substance abuse and mental health services are recommended to consider co-morbid gambling problems in treatment-seeking patients.

The impact of an after-school physical activity program on health-related fitness of mother/daughter pairs: CASPIAN study.

OBJECTIVE: To examine the effectiveness of parental support and involvement in a low-cost intervention for the improvement of health-related fitness of high school girls through an after-school physical activity (PA) program. METHODS: This multi-site study was conducted in 2006-2007 in 7 provinces in Iran. The study population comprised of two groups of children. The first group consisted of 206 children who were randomly selected from female students (7th-10th grade) and their mothers (n=204). Another 60 children (without their mothers) were randomly selected as the control group. Overall, during 12 weeks, 24 sessions of after-school aerobic exercise were held. Health-related fitness data were collected pre- and post-intervention. RESULTS: The findings are based on 470 participants. The after-school PA significantly improved body mass index, resting heart rate, cardiorespiratory fitness, flexibility and muscle strength and endurance in children in both groups, and in mothers. Improvement in the physiological measures of the children in the mother/daughter group was significantly better than the control group. CONCLUSION: The findings suggest that after-school PA may provide an effective model for improving the health-related fitness of high school girls and their mothers. Our data show that family support, including mother's participation, contributes to enhanced health-related achievements in adolescent girls.

Birth outcomes associated with cannabis use before and during pregnancy.

INTRODUCTION: This study aimed to examine the association between cannabis use before and during pregnancy and birth outcomes. RESULTS: Overall, 26.3% of women reported previous use of cannabis and 2.6% reported current use. Multivariate analysis, controlling for potential confounders, including tobacco smoking, alcohol consumption, and use of other illicit drugs, showed that cannabis use in pregnancy was associated with low birth weight (odds ratio (OR) = 1.7; 95% confidence interval (CI): 1.3-2.2), preterm labor (OR = 1.5; 95% CI: 1.1-1.9), small for gestational age (OR = 2.2; 95% CI: 1.8-2.7), and admission to the neonatal intensive care unit (OR = 2.0; 95% CI: 1.7-2.4). DISCUSSION: The results of this study show that the use of cannabis in pregnancy is associated with increased risk of adverse birth outcomes. Prevention programs that address cannabis use during pregnancy are needed. METHODS: Data were from women birthing at the Mater Mothers' Hospital in Brisbane, Australia, over a 7-y period (2000-2006). Women were interviewed in the initial antenatal visit about their use of cannabis and other substances. Records for 24,874 women who provided information about cannabis use, and for whom birth outcomes data were available, were included in the analysis.

Epidemiological and clinical features of Brucella arthritis in 24 children.

BACKGROUND AND OBJECTIVES: Brucellosis is considered the leading zoonotic disease of the Middle East. The disease has a wide spectrum of clinical manifestations and can result in complications with severe morbidity. The aim of this study was to evaluate the frequency, distribution and characteristics of arthritis in Iranian children with brucellosis. DESIGN AND SETTING: A retrospective descriptive study conducted in a referral children center in Tehran from 1997 to 2005. PATIENTS AND METHODS: Arthritis in children with brucellosis who were admitted to a specialized hospital was detected by clinical signs of the involved joint(s) and characteristics of joint fluid aspiration. Socio-demographic information was recorded. RESULTS: Of 96 patients diagnosed with brucellosis, 24 (25%) had Brucella arthritis 14 (58.3%) males and 10 (41.7%) females. Most common manifestations were fever in 21 patients (87.5%) and fatigue in 18 patients (75%). Monoarthritis was recorded in 15 patients (62.5%) of the cases with involvement of the knee in 8 (45%) and hip in 5 (29%), the ankle in 2 (8%) patients while 9 (37.5%) patients suffered from polyarthritis. None of the patients had axial joints involvement. Seventy-five percent of the subjects (18 patients) were from urban areas and 66.7% (16 patients) had consumed un-pasteurized cheese. Recurrence was not seen in any of the 24 patients who received a combination of co-trimoxazole for 6 weeks and gentamicin for 5 days. CONCLUSION: Childhood brucellosis is a challenging disease in Iran that has serious complications like arthritis. Therefore all physicians who work in endemic areas should be familiar with this disease and consider the possibility of brucellosis in all children who present with arthritis and arthralgia.

Illicit drug use before and during pregnancy at a tertiary maternity hospital 2000-2006.

INTRODUCTION AND AIMS: To study the prevalence of use of illicit drugs by women of reproductive age before and during pregnancy and the changes in rates of illicit drug use in pregnancy over recent years. DESIGN AND METHODS: All pregnant women attending the public antenatal clinic over a 7 year period (2000-2006) were routinely interviewed about their use of illicit drugs by a midwife at the antenatal booking visit. MEASUREMENTS: Records for 25,049 women, who self-reported previous and current use of cannabis, amphetamines, ecstasy and heroin, were included in the study. RESULTS: Cannabis was the most common illicit drug used before and during pregnancy; 9.3% of women were engaged in regular use prior to pregnancy and 2.5% were users during pregnancy. A very low proportion of women reported use of amphetamines, ecstasy or heroin in pregnancy. There was an increase in ever regular use and any past use of cannabis, amphetamines and ecstasy over time. CONCLUSIONS: The prevalence of illicit drug use by young women prior to becoming pregnant is of concern. While pregnancy appears to be a strong motivator for women to cease substance use, there is a need to study whether women resume drug use after their baby is born.

Depression following marital problems: different impacts on mothers and their children? A 21-year prospective study.

PURPOSE: With increased rates of marital breakdown it is important to identify the long-term mental health outcomes of marital problems and marital change for mothers and their children. Of particular interest is the possibility that mothers may benefit from leaving a relationship, but their children may not. This study examines the effects of marital quality and marital change on symptoms of depression in mothers and their children over 21 years. METHOD: Data (3,512 mothers and 3,334 children) were from Mater-University of Queensland Study of Pregnancy (MUSP), a population-based birth cohort study, which commenced in Brisbane, Australia, in 1981. Mothers and children were followed up at birth, 6 months and 5, 14 and 21 years after the initial interview. Marital status and marital quality were assessed at 5 and 14 years. Symptoms of depression were assessed in mothers and children at the 21-year follow-up. RESULTS: A poor-quality marital relationship at the 14-year follow-up was associated with increased symptoms of depression in both mothers (+3.3 symptoms) and children (+1.1 symptoms) 7 years later. Symptoms of depression in the mother improved if she changed to unpartnered status (-1.31 symptoms); however, children experienced an increase in depression (+1.30 symptoms). There was a substantial increase in mothers' depression (+3.9 symptoms) associated with a poor reconstructed relationship but no change for children (0.68). CONCLUSION: Marital transitions may improve symptoms of depression in the mothers but not in their children. Clinical decisions for families living in some difficult marital relationships need to take into account the association between maternal and child mental health particularly evidence from clinical samples that remission of depression in the mother improves outcomes for the child.

Association between smoking and respiratory function before and after menopause.

There is a lack of evidence about whether menopausal status influences the effect of smoking on lung function. This study examined the association between smoking and menopausal status and lung function independent of each other. Data were from a cohort of women attending the 21-year follow-up of the Mater University of Queensland Study of Pregnancy. The study was based on 2020 women who provided data on respiratory function, smoking, and menopausal status. A Spirobank G spirometer system was used to measure forced vital capacity (FVC), forced expiratory volume in first second (FEV(1)), and forced expiratory flow between 25 and 75% of forced vital capacity (FEF(25-75)). Smoking and menopausal status were assessed by self-report. Respiratory function was associated with cigarette smoking, menopausal status, and hormone replacement therapy. Regardless of smoking status, postmenopausal women had poorer lung function when compared with premenopausal women. In multivariate analysis, cigarette smoking was associated with lower FVC, FEV(1), and FEF(25-75), with the magnitude of effect being stronger for women who were postmenopausal. The data suggest that the impact of smoking intensifies after menopause. It seems plausible that effective quit-smoking programs, particularly after menopause, may lead to better lung function and reduced morbidity and mortality in women.

Cannabis use and obesity and young adults.

BACKGROUND: There is shortage of evidence about the relationship between use of cannabis and obesity. OBJECTIVES: This study aimed to examine the association between cannabis use and overweight/obesity in young adults. METHODS: Data were from a 21-year follow-up of mothers and their children recruited into the Mater-University of Queensland Study of Pregnancy (MUSP), a longitudinal pre-birth cohort. The study is based on 2566 young adults (1264 males and 1302 females) who had data available on cannabis use and age of initiation to use of cannabis and BMI at the 21-year follow-up (MUSP children). Those who did not provide data on cannabis use and BMI were excluded from the analysis. RESULTS: Frequency of cannabis use and body mass index (BMI) was assessed at the 21-year follow-up. Potential confounders were prospectively measured between the child's birth and the 21-year follow-up. Some 50.9% of young adults reported use of cannabis in the last month or year and 34.1% had BMI ≤ 25. Multivariate analysis showed that those who had used cannabis were less likely to be categorised in the BMI ≥ 25 group with the least prevalence of overweight/obesity being observed in every day cannabis users (odds ratio = .2; 95% confidence interval [CI]:.1-.4). CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE: The existing data suggest lower prevalence of overweight and obesity among young adult cannabis users. Further research is needed to examine the mechanism of this association.

Association of psychiatric disorders, asthma and lung function in early adulthood.

OBJECTIVE: To examine the association between psychiatric disorders, asthma, and lung function in young adults. STUDY DESIGN: Data were from the Mater-University of Queensland Study of Pregnancy (MUSP). The study was based on 2443 young adults (1193 male and 1250 female) for whom data were available on psychiatric disorders, asthma, and respiratory function. Life time and last 12 months' generalized anxiety, panic, posttraumatic stress disorder (PTSD), and depressive disorders were assessed using a computerised version of the Composite International Diagnostic Interview (CIDI-Auto). A Spirobank G spirometer system was used to measure forced vital capacity (FVC), forced expiratory volume in one second (FEV(1)), and forced expiratory flow between 25% and 75% of forced vital capacity (FEF(25-75%)). RESULTS: Participants with mental health disorders were more likely to have experienced asthma before or to use asthma medication at 21 years. However, for both males and females, life time and last 12 months' experience of generalized anxiety, panic, PTSD, and depressive disorders were not statistically significantly associated with FVC, FEV(1), and FEF(25-75%), except a modest association with major depressive disorders for males. CONCLUSION: There is an association between mental health and asthma, but the relationship between mental health and lung function appeared to be confounded by the respondent's gender. More narrowly based prospective studies are required to determine the causal pathway between mental disorders and asthma.

Family poverty over the early life course and recurrent adolescent and young adult anxiety and depression: a longitudinal study.

OBJECTIVES: We determined whether exposure to family poverty over a child's early life course predicts adolescent and young adult anxiety and depression. METHODS: We used a birth cohort study of a sample of women in Brisbane, Australia, who were recruited in early pregnancy and whose children were followed up on at ages 14 and 21 years. Some 2609 mothers and adolescents provided usable data at the 14- and 21-year follow-ups. RESULTS: After adjustment for poverty at other phases, poverty at the 14-year follow-up was the strongest predictor of adolescent and young adult anxiety and depression. The more frequently the child was exposed to poverty, the greater was the risk of that individual being anxious and depressed at both the 14- and 21-year follow-ups. CONCLUSIONS: Family poverty predicts higher rates of adolescent and young adult anxiety and depression. Increased frequency of child exposure to poverty is a consistent predictor of adolescent and young adult anxiety and depression. Repeated experiences of poverty over a child's early life course are associated with increased levels of poor mental health.

Timing and chronicity of family poverty and development of unhealthy behaviors in children: a longitudinal study.

PURPOSE: To examine the impact of the timing and duration of family experiences of poverty over the child/adolescent early life course on child aggressive/delinquent behavior and tobacco and alcohol consumption. METHODS: Data were taken from a large scale population based birth cohort study with repeated follow-ups until 21 years after the birth. Poverty was measured during the pregnancy, 6 months, 5 years, and 14 years after the birth. Aggressive/delinquent behavior was measured at 14- and 21-year follow-ups. Tobacco and alcohol consumption were measured at the 21-year follow-up. RESULTS: In multivariate analysis, family poverty experienced at the 14-year follow-up predicted persistent aggressive/delinquent behavior as well as smoking and higher levels of alcohol consumption at the 21-year follow-up. However, the strongest associations were for recurrent experiences of family poverty, with the group that experienced repeated poverty (3-4 times) being more than twice more likely to be aggressive/delinquent at both 14 and 21 years, and to drink more than one glass of alcohol per day at 21 years. CONCLUSIONS: Repeated experiences of poverty in early childhood and adolescence are strongly associated with a number of negative health-related behavior outcomes. Experience of poverty in the early adolescence seems to be the most sensitive period for such exposure.

Comparative study of skin sebum and elasticity level in patients with sulfur mustard-induced dermatitis and healthy controls.

BACKGROUND: Sulfur mustard (SM) - a chemical agent - has both acute and chronic effects on skin. Xerosis, which is deemed to be due to the damage of hydrolipidic barrier of the skin, is the most common complaint of veterans exposed to the chemical. This study was designed to evaluate skin sebum and elasticity in veterans with a history of SM contact. METHODS: Three hundred and ten subjects were enrolled in this study and were divided into four groups: SM-exposed patients with current skin lesions (n=87); SM-exposed patients without skin lesions (n=71); patients with dermatitis (n=78); and normal controls (n=74). The skin sebum and elasticity were measured in four areas (forehead, suprasternal, palm and back of the hands) using a Sebumeter and a Reviscometer. RESULTS: Skin sebum was higher in participants who presented with dermatitis and had history of contact with SM than others; the difference was only statistically significant on the forehead. There was no significant difference in the skin elasticity between the four groups. CONCLUSION: While SM may increase skin sebum in long term, there is no evidence that it has a substantial effect on skin elasticity.

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.

Drinking water fluoridation in South East Queensland: a cost-effectiveness evaluation.

OBJECTIVE: The aim of this study is to examine cost-effectiveness of fluoridation of drinking water supplies for Brisbane and South East Queensland. The benefits conveyed are expressed in reduced costs of dental treatment and years of life with dental caries as a disability. METHODS: The analysis utilises a developed life table modelling initial cohort of 36,322 newborns, which when applied to the target population equals to 181,925 persons in the age group 2-100 years, 338,617 persons in the age group 7-100 years and 390,524 persons in the age group 12-100 years respectively. The analysis was conducted using a real discount rate of 3%. Sensitivity analyses investigated the effects of varying the parameters such as: discount rate, costs of dental treatment and costs of fluoridation plant. Uncertainty analysis was also conducted on costs and the measure of ratio of decayed, missing, filled teeth surfaces in deciduous dentition between the cities of Brisbane (non-fluoridated) and Townsville (fluoridated). RESULTS: If fluoridation was implemented there would be a total saving of $10,437.43 (95% CI 6,406.50- 14,035.35) disability-adjusted life years (DALYs) and AU$ 665,686,529 (95% CI -$973,573,625- $381,322,176). This result is both desirable and dominant as more DALYs are saved along with significant cost savings. CONCLUSION: Fluoridation remains still a very cost-effective measure for reducing dental decay.

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.

Efficacy of combined levothyroxine and liothyronine as compared with levothyroxine monotherapy in primary hypothyroidism: a randomized controlled trial.

OBJECTIVES: To examine the efficacy of combination therapy with levothyroxine and liothyronine in improvement of general health, psychological problems, and metabolic status in primary hypothyroidism. METHODS: Seventy-one patients diagnosed with primary hypothyroidism were randomly allocated into two study groups: the first group received usual dose of levothyroxine and the second group received combination of levothyroxine and liothyronine for at least 4 months. The main outcomes were psychosocial problems (Goldberg's General Health Questionnaire, GHQ-28), bodyweight, heart rate, blood pressure, and serum lipid levels. RESULTS: In both groups serum thyroid-stimulating hormone levels remained unchanged compared with baseline. Psychosocial scores, body weight, heart rate, blood pressure, and lipid profile in the two groups remained constant. The only exception was a small but significant reduction in anxiety/insomnia in combined treatment group as compared with monotherapy. CONCLUSIONS: The data do not support the hypothesis that combined therapy improves the well-being and general health of patients.

Childhood sexual abuse and cannabis use in early adulthood: findings from an Australian birth cohort study.

Childhood sexual abuse (CSA) is associated with a wide range of health problems later in life. The impact of CSA on young adults' use of cannabis remains under-studied. We examined the extent to which exposure to CSA was associated with increased rates of use of cannabis in early adulthood in a birth cohort of 3,285 Australian children followed-up to the age of 21 years, when retrospective reports of CSA were obtained from sample participants along with information on their use of cannabis at 21 years. Young adult men and women who reported experiencing CSA had significantly higher rates of frequent use of cannabis in early adulthood, defined as use of cannabis at least "every few days." In multivariate analyses, men who reported a history of CSA had an odds ratio (OR) of 2.1 (95% CI = 1.1-3.9) for frequent use of cannabis at the age of 21 years. For women, there was an OR of 3.9 (95% CI = 2.4-6.3). Family and individual factors measured earlier in the study did not confound these associations. The findings suggest that children experiencing CSA have a substantially greater risk of use of cannabis and, in particular, its frequent use in early adulthood. Further research is required to explore factors that explain the pathway linking CSA and use of cannabis in early adulthood.

Early pubertal maturation in the prediction of early adult substance use: a prospective study.

AIMS: To examine whether self-reporting a later stage of pubertal development in early adolescence predicts young adults' use of illicit drugs. DESIGN: Population-based prospective birth cohort study. SETTING: Follow-up of a cohort of mothers and their children, recruited between 1981 and 1983. PARTICIPANTS: Cohort of 2710 young adults who completed a self-report questionnaire about their use of cannabis and amphetamines at the 21-year follow-up. MEASUREMENTS: Young adults' use of cannabis and amphetamines were measured at the 21-year follow-up. Stage of pubertal development was assessed at the 14-year follow-up. Potential confounding and mediating variables were assessed between birth and when the child was 14 years. FINDINGS: Of 2,710 young adults, 49.9% (47.3 females and 52.7% males) reported that they had used cannabis and 21.0% (18.9% females and 23.3% males) reported that they had used amphetamines and cannabis by 21 years. In multivariate analyses, adolescents with a later stage of puberty were more likely to use cannabis or amphetamines in young adulthood. This association was not confounded by mother's education or child's gender and age. Part of the relationship was explained by the higher frequency of child externalizing behaviour at 14 years. CONCLUSIONS: The findings warrant further attention to puberty as a sensitive period in an individual's development. With regard to prevention, there is a need to understand more about the pathways between pubertal development, child behaviour problems and substance use.