Epidemiology of childhood conduct problems in Brazil: systematic review and meta-analysis

This study aimed to review evidence on the prevalence of and risk factors for conduct problems in Brazil.We searched electronic databases and contacted Brazilian researchers up to 05/2012. Studies were included in the review if they reported the prevalence of or risk factors for conduct problems, conduct disorder, or oppositional defiant disorder for 100 + Brazilian children aged a parts per thousand currency sign18 years, systematically sampled in schools or the community. Prevalence rates and sex differences were meta-analysed. Risk factor studies were reviewed one by one.The average prevalence of conduct problems in screening questionnaires was 20.8 %, and the average prevalence of conduct disorder/oppositional defiant disorder was 4.1 %. There was systematic variation in the results of screening studies according to methodology: recruitment location, informants, instruments, impairment criterion for case definition, and response rates. Risk factors previously identified in high-income countries were mainly replicated in Brazil, including comorbid mental health problems, educational failure, low religiosity, harsh physical punishment and abuse, parental mental health problems, single parent family, and low socioeconomic status. However, boys did not always have higher risk for conduct problems than girls.Studies using screening questionnaires suggest that Brazilian children have higher rates of conduct problems than children in other countries, but diagnostic studies do not show this difference. Risk factors in Brazil were similar to those in high-income countries, apart from child sex. Future research should investigate developmental patterns of antisocial behaviour, employ a variety of research designs to identify causal risk mechanisms, and examine a broader range of risk factors.Wellcome TrustUniv Cambridge, Dept Psychiat, Cambridge CB2 8AH, EnglandUniv Fed Pelotas, Postgrad Program Epidemiol, Pelotas, BrazilUniv São Paulo, Dept Psychiat, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Psychiat, Pelotas, BrazilUniversidade Federal de São Paulo, Dept Psychiat, Pelotas, BrazilWellcome Trust: 089963/Z/09/ZWeb of Scienc

DRD4 rare variants in attention-deficit/hyperactivity disorder (ADHD) : further evidence from a birth cohort study

The dopamine receptor D4 (DRD4) is one of the most studied candidate genes for Attention-Deficit/Hyperactivity Disorder (ADHD). An excess of rare variants and non-synonymous mutations in the VNTR region of 7R allele in ADHD subjects was observed in previous studies with clinical samples. We hypothesize that genetic heterogeneity in the VNTR is an important factor in the pathophysiology of ADHD. The subjects included in the present study are members of the 1993 Pelotas Birth Cohort Study (N=5,249). We conducted an association study with the 4,101 subjects who had DNA samples collected. The hyperactivity-inattention scores were assessed through the parent version of the Strengths and Difficulties Questionnaire at 11 and 15 years of age. The contribution of allele’s length and rare variants to high hyperactivity/inattention scores predisposition was evaluated by multivariate logistic regression. No effect of allele length was observed on high scores of hyperactivity-inattention. By contrast, when resequencing/haplotyping was conducted in a subsample, all 7R rare variants as well as non-synonymous 7R rare variants were associated with high hyperactivity/inattention scores (OR=2.561; P=0.024 and OR=3.216; P=0.008 respectively). A trend for association was observed with 4R rare variants. New coding mutations covered 10 novel motifs and many of them are previously unreported deletions leading to different stop codons. Our findings suggest a contribution of DRD4 7R rare variants to high hyperactivity-inattention scores in a population-based sample from a large birth cohort. These findings provide further evidence for an effect of DRD4 7R rare variants and allelic heterogeneity in ADHD genetic susceptibility

Continuity of psychiatric disorders between 6 and 11 years of age in the 2004 Pelotas Birth Cohort

Objective: To investigate the incidence and homotypic and heterotypic continuity of psychiatric disorders between ages 6 and 11. Methods: In 2004, all live births in the city of Pelotas, Brazil, were recorded (n=4,231). Psychiatric disorders were assessed by the Strengths and Difficulties Questionnaire (SDQ). SDQ subscale scores (emotional symptoms, conduct problems, hyperactivity/inattention, and peer relationship problems) were categorized as normal or abnormal. To examine associations between problems over time, odds ratios were computed using logistic regression. Results: Any SDQ difficulty was observed in 350 children (10.4%, 95%CI 9.4-11.5) at age 6 and 476 (14.2%, 95%CI 13.0-15.4) at age 11, with a higher prevalence among boys at both ages. Between ages 6 and 11, there was a 50 and a 45% increase in the prevalence of emotional and hyperactivity/ inattention symptoms, respectively. Among those who had any SDQ difficulty at age 6, that status persisted in 81% at age 11. We found homotypic continuity of emotional symptoms, conduct problems, hyperactivity/inattention, and peer relationship problems. Conclusions: Our results indicate an increasing incidence of psychiatric disorders in this age group, with rates of disorders and continuity patterns similar to those observed in other studie

Perinatal and sociodemographic factors at birth predicting conduct problems and violence to age 18 years: comparison of Brazilian and British birth cohorts.

This is the final published version. It was first published by Wiley at http://dx.doi.org/10.1111/jcpp.12369BACKGROUND: Many low- and middle-income countries have high levels of violence. Research in high-income countries shows that risk factors in the perinatal period are significant precursors of conduct problems which can develop into violence. It is not known whether the same early influences are important in lower income settings with higher rates of violence. This study compared perinatal and sociodemographic risk factors between Brazil and Britain, and their role in explaining higher rates of conduct problems and violence in Brazil. METHODS: Prospective population-based birth cohort studies were conducted in Pelotas, Brazil (N = 3,618) and Avon, Britain (N = 4,103). Eleven perinatal and sociodemographic risk factors were measured in questionnaires completed by mothers during the perinatal period. Conduct problems were measured in questionnaires completed by mothers at age 11, and violence in self-report questionnaires completed by adolescents at age 18. RESULTS: Conduct problems were predicted by similar risk factors in Brazil and Britain. Female violence was predicted by several of the same risk factors in both countries. However, male violence in Brazil was associated with only one risk factor, and several risk factor associations were weaker in Brazil than in Britain for both females and males. Almost 20% of the higher risk for conduct problems in Brazil compared to Britain was explained by differential exposure to risk factors. The percentage of the cross-national difference in violence explained by early risk factors was 15% for females and 8% for males. CONCLUSIONS: A nontrivial proportion of cross-national differences in antisocial behaviour are related to perinatal and sociodemographic conditions at the start of life. However, risk factor associations are weaker in Brazil than in Britain, and influences in other developmental periods are probably of particular importance for understanding male youth violence in Brazil.The 1993 Pelotas Birth Cohort Study is currently supported by the Wellcome Trust through the programme entitled Major Awards for Latin America on Health Consequences of Population Change (Grant: 086974/Z/08/Z). The European Union, National Support Program for Centers of Excellence (PRONEX), the Brazilian National Research Council (CNPq), and the Brazilian Ministry of Health supported previous phases of the study. The UK Medical Research Council and the Wellcome Trust (Grant: 092731) and the University of Bristol provide core support for ALSPAC. Additional support for the data collected at age 18 in this paper was provided by UK Medical Research Council (Grants G0800612 and G0802736).The research for this specific article was funded by the Wellcome Trust (Grant: 089963/Z/09/Z). The authors are extremely grateful to all the families who took part in this study, the midwives for their help in recruiting them, and the whole ALSPAC team, which includes interviewers, computer and laboratory technicians, clerical workers, research scientists, volunteers, managers, receptionists and nurses. Yulia Shenderovich helped prepare the tables. The authors have declared that they have no competing or potential conflicts of interest

The effects of two early parenting interventions on child aggression and risk for violence in Brazil (The PIÁ Trial): protocol for a randomised controlled trial

Background Children in many low- and middle-income countries (LMICs) are at high risk for exposure to violence and later violent behaviour. The World Health Organization has declared an urgent need for the evaluation and implementation of low-cost parenting interventions in LMICs to prevent violence. Two areas of significant early risk are harsh parenting and poor child cognitive and socio-emotional development. Parenting interventions suitable for LMIC contexts have been developed targeting these risk factors and have been shown to have promising effects. However, their impact on child aggression, a key precursor of violence, has yet to be determined. The Pelotas Trial of Parenting Interventions for Aggression (PIÁ) has been designed to address this issue. Methods We are conducting a randomised controlled trial to evaluate two early parenting interventions for mothers of children aged between 30 and 42 months in a Brazilian city. The first of these, dialogic book-sharing (DBS), aims to promote child cognitive and socio-emotional development; and the second, the ACT Raising Safe Kids Program (ACT), is designed to reduce harsh parenting. These interventions are being compared with a control group receiving neither intervention. Three hundred and sixty-nine families in a birth cohort are being randomly allocated to one of the three groups (DBS, ACT, Control). Facilitators deliver the interventions to groups of five to 10 mothers at weekly sessions for 8 weeks in DBS and 9 weeks in ACT. Independent assessments of parenting and child development are being made before the interventions, shortly afterwards, and at follow-up 6 months later. The primary outcome is child aggression, and the two main secondary outcomes are: (1) child cognitive and socio-emotional development and (2) harsh parenting. Longer-term outcomes will be investigated as the birth cohort is followed into late childhood, adolescence, and adulthood. Discussion The Pelotas Trial of Parenting Interventions for Aggression (PIÁ) aims to evaluate the impact of two early parenting interventions on child aggression and several other key risk factors for the development of violence, including aspects of parenting and child cognition and socio-emotional functioning. The study is being carried out in a LMIC context where violence constitutes a major social and health burden. Since the two interventions are brief and, with modest levels of training, readily deliverable in LMIC settings, a demonstration that they benefit parenting and reduce risk factors for violence would be of major significance

Childhood behaviour problems predict crime and violence in late adolescence: Brazilian and British birth cohort studies.

PURPOSE: Most children live in low- and middle-income countries (LMICs), many of which have high levels of violence. Research in high-income countries (HICs) shows that childhood behaviour problems are important precursors of crime and violence. Evidence is lacking on whether this is also true in LMICs. This study examines prevalence rates and associations between conduct problems and hyperactivity and crime and violence in Brazil and Britain. METHODS: A comparison was made of birth cohorts in Brazil and Britain, including measures of behaviour problems based on parental report at age 11, and self-reports of crime at age 18 (N = 3,618 Brazil; N = 4,103 Britain). Confounders were measured in the perinatal period and at age 11 in questionnaires completed by the mother and, in Brazil, searches of police records regarding parental crime. RESULTS: Conduct problems, hyperactivity and violent crime were more prevalent in Brazil than in Britain, but nonviolent crime was more prevalent in Britain. Sex differences in prevalence rates were larger where behaviours were less common: larger for conduct problems, hyperactivity, and violent crime in Britain, and larger for nonviolent crime in Brazil. Conduct problems and hyperactivity predicted nonviolent and violent crime similarly in both countries; the effects were partly explained by perinatal health factors and childhood family environments. CONCLUSIONS: Conduct problems and hyperactivity are similar precursors of crime and violence across different social settings. Early crime and violence prevention programmes could target these behavioural difficulties and associated risks in LMICs as well as in HICs.This is the final published version, published by Springer in Social Psychiatry and Psychiatric Epidemiology (http://link.springer.com/article/10.1007%2Fs00127-014-0976-z)

Socioeconomic changes and adolescent psychopathology in a brazilian birth cohort study

Purpose: To investigate the effects of socioeconomic changes from birth to 11 years of life on emotional, conduct, and attentional/hyperactivity problems in 15-year-old adolescents, from the 1993 Pelotas (Brazil) birth cohort study. Methods: The original cohort was composed of 5,249 hospital-born children whose mothers answered a questionnaire. We conducted interviews with 87.5% and 85.7% of the original cohort in 2004e2005 and 2008, respectively. We divided family income changes into nine possible categories based on two assessment points (birth and 11 years of age) and three income levels. To assess the psychopathology of the adolescents at 15 years of age, 4,423 mothers answered the Strengths and Difficulties Questionnaire. Results: Adolescents who were always poor or who became poor between birth and 11 years of age had greater conduct problems at 15 years of age. There was no consistent association between poverty and emotional and attentional/hyperactivity problems. Conclusions: The effects of income change were more specific to conduct problems than to emotional and attentional/hyperactivity problems, similar to what has been previously described in developed countries

Prevalência e determinantes precoces dos transtornos mentais comuns na coorte de nascimentos de 1982, Pelotas, RS

OBJECTIVE: To estimate the prevalence of common mental disorders and assess its association with risk factors in a cohort of young adults. METHODS: Cross-sectional study nested in a 1982 birth cohort study conducted in Pelotas, Southern Brazil. In 2004-5, 4,297 subjects were interviewed during home visits. Common mental disorders were assessed using the Self-Report Questionnaire. Risk factors included socioeconomic, demographic, perinatal, and environmental variables. The analysis was stratified by gender and crude and adjusted prevalence ratios were estimated by Poisson regression. RESULTS: The overall prevalence of common mental disorders was 28.0%; 32.8% and 23.5% in women and men, respectively. Men and women who were poor in 2004-5, regardless of their poor status in 1982, had nearly 1.5-fold increased risk for common mental disorders (pOBJETIVO: Estimar la prevalencia de trastornos mentales comunes y su asociación con factores de riesgo en una cohorte de adultos jóvenes. MÉTODOS: Estudio transversal anidado a la cohorte de nacimientos de 1982 de Pelotas (Sur de Brasil). En 2004-5, 4.297 individuos fueron entrevistados en visita domiciliar. La probabilidad de trastornos mentales comunes fue estimada por el Self-Report Questionnaire. Los factores de riesgo incluyeron variables socioeconómicas, demográficas, perinatales y ambientales. El análisis fue estratificado por sexo y las razones de prevalencia simples y ajustadas fueron estimadas utilizándose regresión de Poisson. RESULTADOS: La prevalencia de trastornos mentales comunes en la población general fue de 28,0%; 32,8% y 23,5%, respectivamente, entre mujeres y hombres. Independientemente de la pobreza en 1982, hombres y mujeres pobres en 2004-5 presentaron riesgo aproximado de 1,5 para esos trastornos (pOBJETIVO: Estimar a prevalência de transtornos mentais comuns e sua associação com fatores de risco numa coorte de adultos jovens. MÉTODOS: Estudo transversal aninhado à coorte de nascimentos de 1982 de Pelotas, RS. Em 2004-5, 4.297 indivíduos foram entrevistados em visita domiciliar. A probabilidade de transtornos mentais comuns foi estimada pelo Self-Report Questionnaire. Os fatores de risco incluíram variáveis socioeconômicas, demográficas, perinatais e ambientais. A análise foi estratificada por sexo e as razões de prevalência simples e ajustadas foram estimadas utilizando-se regressão de Poisson. RESULTADOS: A prevalência de transtornos mentais comuns na população geral foi 28,0%; 32,8% e 23,5%, respectivamente, entre mulheres e homens. Independentemente da pobreza em 1982, homens e mulheres pobres em 2004-5 apresentaram risco aproximado de 1,5 para esses transtornos (

ADHD in DSM-5 : a field trial in a large, representative sample of 18- to 19-year-old adults

Background. The DSM criteria for adult attention-deficit/hyperactivity disorder (ADHD) have not been tested in American Psychiatric Association (APA) field trials for either DSM-IV or DSM-5. This study aimed to assess: (a) the prevalence of ADHD according to DSM-5 criteria; (b) the factor solution that provides the best fit for ADHD symptoms; (c) the symptoms with the highest predictive value for clinical impairment; and (d) the best symptomatic threshold for each ADHD dimension (inattention and hyperactivity/impulsivity). Method. Trained psychologists evaluated 4000 young adults from the 1993 Pelotas Birth Cohort Study with an instrument covering all DSM-5 ADHD criteria. A series of confirmatory factor analyses (CFAs) tested the best factor structure. Complex logistic regressions assessed differential contributions of each symptom to clinical impairment. Receiver-operating characteristic (ROC) analyses tested which would be the best symptomatic cut-off in the number of symptoms for predicting impairment. Results. The prevalence of DSM-5 ADHD was 3.55% [95% confidence interval (CI) 2.98–4.12]. The estimated prevalence of DSM-IV ADHD was 2.8%. CFA revealed that a bifactor model with a single general factor and two specific factors provided the best fit for DSM-5 symptoms. Inattentive symptoms continued to be the most important predictors of impairment in adults. The best cut-offs were five symptoms of inattention and four symptoms of hyperactivity/ impulsivity. Conclusions. Our results, combined with previous findings, suggest a 27% increase in the expected prevalence of ADHD among young adults, comparing DSM-IV to DSM-5 criteria. The DSM-5 symptomatic organization derived a similar factor structure for adults as DSM-IV symptoms. Data using DSM-5 criteria support lowering the symptomatic threshold for diagnosing ADHD in adults

What are the causal effects of breastfeeding on IQ, obesity and blood pressure? Evidence from comparing high-income with middle-income cohorts

Background A novel approach is explored for improving causal inference in observational studies by comparing cohorts from high-income with low- or middle-income countries (LMIC), where confounding structures differ. This is applied to assessing causal effects of breastfeeding on child blood pressure (BP), body mass index (BMI) and intelligence quotient (IQ)