Gene - maltreatment interplay in adult ADHD symptoms: main role of a gene-environment correlation effect in a Brazilian population longitudinal study.

Childhood maltreatment correlates with attention-deficit/hyperactivity disorder (ADHD) in previous research. The interaction between ADHD genetic predisposition and maltreatment's impact on ADHD symptom risk remains unclear. We aimed to elucidate this relationship by examining the interplay between a polygenic score for ADHD (ADHD-PGS) and childhood maltreatment in predicting ADHD symptoms during young adulthood. Using data from the 2004 Pelotas (Brazil) birth cohort comprising 4231 participants, we analyzed gene-environment interaction (GxE) and correlation (rGE). We further explored rGE mechanisms through mediation models. ADHD symptoms were assessed at age 18 via self-report (Adult Self Report Scale - ASRS) and mother-reports (Strength and Difficulties Questionnaire - SDQ). The ADHD-PGS was derived from published ADHD GWAS meta-analysis. Physical and psychological child maltreatment was gauged using the Parent-Child Conflict Tactics Scale (CTSPC) at ages 6 and 11, with a mean score utilized as a variable. The ADHD-PGS exhibited associations with ADHD symptoms on both ASRS (ß = 0.53; 95% CI: 0.03; 1.03, p = 0.036), and SDQ (ß = 0.20; 95% CI: 0.08; 0.32, p = 0.001) scales. The total mean maltreatment score was associated with ADHD symptoms using both scales [(ßASRS = 0.51; 95% CI: 0.26;0.77) and (ßSDQ = 0.24; 95% CI: 0.18;0.29)]. The ADHD-PGS was associated with total mean maltreatment scores (ß = 0.09; 95% CI: 0.01; 0.17; p = 0.030). Approximately 47% of the total effect of ADHD-PGS on maltreatment was mediated by ADHD symptoms at age 6. No evidence supported gene-environment interaction in predicting ADHD symptoms. Our findings underscore the significant roles of genetics and childhood maltreatment as predictors for ADHD symptoms in adulthood, while also indicating a potential evocative mechanism through gene-environment correlation.

Maternal depression and child development at 3 years of age: a longitudinal study in a Brazilian child development promotion program.

BACKGROUND: We tested the hypothesis that children of non-depressed mothers perform better in a developmental test at 3 years than children of depressed mothers. METHOD: Longitudinal analysis from a trial to assess the impact of a child development promotion program in 30 Brazilian municipalities. Mothers and children were appraised at first-year post-partum, 1 and 3 years after enrollment. Child development was assessed through the Ages and Stages Questionnaire (ASQ3) and maternal depression through the Edinburgh Postnatal Depression Scale (EPDS). Crude and adjusted beta coefficients were obtained by linear regression before and after multiple imputation. RESULTS: In total, 2098 mother/child dyads were included and 8.2% of the mothers had persistent depressive symptoms. There was a decrease in ASQ3 as the number of follow-ups with EPDS ≥ 10 increased (p for trend <0.001). In adjusted analysis, the direction of the association persisted but lost statistical significance. After multiple imputation, children from mothers with EPDS ≥ 10 in three follow-ups presented a decrease of about 14 points in ASQ3 (adjusted beta coefficient = -13.79; -22.59 to -5.00) (p for trend = 0.001). CONCLUSIONS: Identification of women at increased risk of depression should be among the primary health care sector priorities in maternal and child health in Brazil. IMPACT: In our population study, almost one in every ten women presented persistent depression symptoms across the first 3 years postpartum. In adjusted analysis there was a detrimental impact of persistent maternal depression on child development at 3 years of age. The persistent exposure to maternal depression across early childhood negatively influences children's development. Considering its prevalence, identification of women at increased risk of depression should be among the primary health care sector priorities in maternal and child health in Brazil.

Trajectory of maternal depression and parasomnias.

Maternal depressive symptoms are associated with poorer sleep quality in their children. Although parasomnias can occur at any age, this group of sleep disorders is more common in children. The aim of this study was to assess whether maternal depression trajectories predict parasomnias at the age of 11 years. Data were from a Birth Cohort of 4231 individuals followed in the city of Pelotas, Brazil. Maternal depressive symptoms were assessed with the Edinburgh Postnatal Depression Scale (EPDS) at 12, 24, and 48 months, and 6 and 11 years postpartum. Maternal depression trajectories were calculated using a group-based modelling approach. Information on any parasomnias (confused arousals, sleepwalking, night terrors, and nightmares) was provided by the mother. Five trajectories of maternal depressive symptoms were identified: chronic-low (34.9%), chronic-moderate (41.4%), increasing (10.3%), decreasing (8.9%), and chronic-high (4.4%). The prevalence of any parasomnia at the age of 11 years was 16.8% (95% confidence interval [CI] 15.6%-18.1%). Confusional arousal was the most prevalent type of parasomnia (14.5%) and varied from 8.7% to 14.7%, 22.9%, 20.3%, and 27.5% among children of mothers at chronic-low, moderate-low, increasing, decreasing, and chronic-high trajectories, respectively (p < 0.001). Compared to children from mothers in the chronic-low trajectory, the adjusted prevalence ratio for any parasomnia was 1.58 (95% CI 1.29-1.94), 2.34 (95% CI 1.83-2.98), 2.15 (95% CI 1.65-2.81), and 3.07 (95% CI 2.31-4.07) among those from mothers in the moderate-low, increasing, decreasing, and chronic-high trajectory groups, respectively (p < 0.001). In conclusion, parasomnias were more prevalent among children of mothers with chronic symptoms of depression.

Structural Relationships between Asthma and Dental Caries in Children: A Birth Cohort Study in Southern Brazil.

INTRODUCTION: There is an inconclusive causal association between asthma symptoms and dental caries in the primary dentition. This study aimed to investigate, using SEM (structural equation modeling), a possible causal relation between asthma and dental caries in the primary dentition. METHODS: Using data from the 2004 Pelotas Birth Cohort Study, a sub-sample of 1,303 individuals was selected. Dental caries was clinically evaluated at 5 years old based on decayed, missing, and filled tooth (dmft) index criteria. Asthma-related symptoms (wheezing and shortness of breath) at 1- and 4-year-olds composed a latent variable and were the main exposures to caries occurrence. SEM was used to identify possible direct, indirect, and mediated effects of asthma in primary dentition dental caries. RESULTS: The general prevalence of caries at age 5 was 1.95 (SD: 3.56). When comparing the dmft values for children with asthma symptoms and those without, they presented similar values in both periods where asthma symptoms were evaluated (1- and 4-year-old). SEM analysis showed that asthma was neither directly nor indirectly related to dental caries. CONCLUSION: Asthma, using a latent variable constructed based on asthma symptoms, showed no causal effect on dental caries occurrence in the primary dentition.

Early risk factors for conduct problem trajectories from childhood to adolescence: the 2004 Pelotas (BRAZIL) Birth Cohort.

Conduct problems are associated with an increased risk of a wide range of physical, mental, and social problems. However, there is still uncertainty about how early risk factors differentiate different developmental patterns of conduct problems and whether findings replicate across diverse social contexts. We aimed to identify developmental trajectories of conduct problems, and test early risk factors, in the 2004 Pelotas Birth Cohort in Brazil. Conduct problems were measured at ages 4, 6, 11, and 15 years from caregiver reports on the Child Behaviour Checklist (CBCL) and Strengths and Difficulties Questionnaire (SDQ). Conduct problem trajectories were estimated using group-based semi-parametric modeling (n = 3938). Multinomial logistic regression was used to examine associations between early risk factors and conduct problem trajectories. We identified four trajectories: three with elevated conduct problems, including early-onset persistent (n = 150; 3.8%), adolescence-onset (n = 286; 17.3%), and childhood-limited (n = 697; 17.7%), and one with low conduct problems (n = 2805; 71.2%). The three elevated conduct problem trajectories were associated with a wide range of sociodemographic risk factors, prenatal smoking, maternal mental health, harsh parenting, childhood trauma, and child neurodevelopmental risk factors. Early-onset persistent conduct problems were particularly associated with trauma, living without a father figure, and attention difficulties. The four trajectories of conduct problems from ages 4 to 15 years in this Brazilian cohort have similar longitudinal patterns to those identified in high-income countries. The results confirm previous longitudinal research and developmental taxonomic theories on the etiology of conduct problems in a Brazilian sample.

Women's multi-partner behavior, multi-partner fertility, and pregnancy outcomes: findings from the 2004 Pelotas Birth Cohort.

STUDY QUESTION: Do women with multi-partner fertility or multi-partner behavior conceive more often than women with a single partner? SUMMARY ANSWER: Women with multi-partner behavior conceived more frequently and had more children than non-multi-partner women and multi-partner fertility women. WHAT IS KNOWN ALREADY: Some women experience having biological children with more than one partner: those women are considered as multi-partner fertility. Women with multi-partner fertility have more children and are substantially less likely to have planned their first birth. Individuals with multi-partner fertility become parents at a younger age, largely with unintended first births, and often do so outside of marriage, compared to parents with two or more children from only one partner. Unmarried women, particularly, are at greater risk of having unintended births. Studies are still scarce and there is a need to assess the contribution of women's multi-partners fertility and multi-partner behavior to family composition, particularly in low- and middle-income countries. STUDY DESIGN, SIZE, DURATION: This longitudinal birth cohort study evaluated 1215 mothers whose children belonging to the 2004 Pelotas Birth Cohort were their first pregnancy, and who attended the perinatal, 48-month, 6-year, and 11-year follow-ups. Information was obtained from responses to a questionnaire. The number of years at risk of having children was treated as the exposure, and woman's multi-partner behavior and multi-partner fertility, dichotomized as 'Yes' or 'No', were considered endogenous treatment variables. PARTICIPANTS/MATERIALS, SETTING, METHODS: Data from mothers with a first pregnancy, and with information available from the perinatal, 48-month, 6-year, and 11-year follow-ups, were evaluated. The exposures studied were women's multi-partner behavior and multi-partner fertility (i.e. conceiving/giving birth), and the outcomes evaluated were the number of pregnancies, the number of children currently alive, and experience of unintended pregnancies from the birth of the child belonging to the 2004 birth cohort until 11 years later. Crude and adjusted risk ratios (RRs) were estimated through Poisson regression with endogenous treatment effects, robust standard errors, and their respective 95% CI. MAIN RESULTS AND THE ROLE OF CHANCE: Multi-partner behavior women had 16% (RR 1.16; 95% CI: 1.08-1.25) and 11% (RR 1.11; 95% CI 1.03-1.19) greater risk of having a new pregnancy and having more children alive, respectively, than those with non-multi-partner behavior. Women with multi-partner fertility had a 23% (RR 1.23; 95% CI: 1.11-1.37) and 20% (RR 1.20; 95% CI: 1.08-1.33) higher risk of having a new pregnancy and having more children alive, respectively, than single-partner fertility mothers. Women who had multiple partners (i.e. behavior), as well as those with multi-partner fertility, showed a lesser proportion of unintended pregnancies when compared to the non-multi-partner ones (34.08%; 95% CI: 28.12-40.60 vs 36.17%; 95% CI: 31.93-40.63), compared to their counterparts' single partners fertility (33.16%; 95% CI: 26.83-40.17 vs 36.26%; 95% CI: 31.85-40.92), although these findings were not statistically significant. LIMITATIONS, REASONS FOR CAUTION: The mothers who were not included in the study owing to missing data for some of the follow-up had 5-11 years of education, a low socio-economic level, and were younger, thus the number of pregnancies may be underestimated because these groups presented a high number of pregnancies and children alive. We did not have information about the complete woman's conjugal history. Therefore, misclassification error of the exposure may be present and, consequently, the measures of association may be underestimated. Furthermore, this study was not truly representative of the Pelotas study female population. WIDER IMPLICATIONS OF THE FINDINGS: In this study of multi-partner behavior and fertility, women who have multiple partners may be less likely to get married and have a stable partner. Compared to single-partner women, multi-partner fertility and multi-partner behavior women may predominantly become pregnant for the purpose of having children, rather than accidentally. STUDY FUNDING/COMPETING INTEREST(S): This article is based on data from the study 'Pelotas Birth Cohort, 2004' conducted by the Postgraduate Program in Epidemiology at the Universidade Federal de Pelotas, with the collaboration of the Brazilian Public Health Association (ABRASCO). From 2009 to 2013, the Wellcome Trust supported the 2004 birth cohort study. The World Health Organization, National Support Program for Centers of Excellence (PRONEX), Brazilian National Research Council (CNPq), Brazilian Ministry of Health, and Children's Pastorate supported previous phases of the study, and also was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior-Brasil (CAPES)-Finance Code 001. The authors declare that the supported agencies have no role in any step of performing this study. No conflicts of interest exist. TRIAL REGISTRATION NUMBER: N/A.

Quality of vital event data for infant mortality estimation in prospective, population-based studies: an analysis of secondary data from Asia, Africa, and Latin America.

INTRODUCTION: Infant and neonatal mortality estimates are typically derived from retrospective birth histories collected through surveys in countries with unreliable civil registration and vital statistics systems. Yet such data are subject to biases, including under-reporting of deaths and age misreporting, which impact mortality estimates. Prospective population-based cohort studies are an underutilized data source for mortality estimation that may offer strengths that avoid biases. METHODS: We conducted a secondary analysis of data from the Child Health Epidemiology Reference Group, including 11 population-based pregnancy or birth cohort studies, to evaluate the appropriateness of vital event data for mortality estimation. Analyses were descriptive, summarizing study designs, populations, protocols, and internal checks to assess their impact on data quality. We calculated infant and neonatal morality rates and compared patterns with Demographic and Health Survey (DHS) data. RESULTS: Studies yielded 71,760 pregnant women and 85,095 live births. Specific field protocols, especially pregnancy enrollment, limited exclusion criteria, and frequent follow-up visits after delivery, led to higher birth outcome ascertainment and fewer missing deaths. Most studies had low follow-up loss in pregnancy and the first month with little evidence of date heaping. Among studies in Asia and Latin America, neonatal mortality rates (NMR) were similar to DHS, while several studies in Sub-Saharan Africa had lower NMRs than DHS. Infant mortality varied by study and region between sources. CONCLUSIONS: Prospective, population-based cohort studies following rigorous protocols can yield high-quality vital event data to improve characterization of detailed mortality patterns of infants in low- and middle-income countries, especially in the early neonatal period where mortality risk is highest and changes rapidly.

Impact of covid-19 pandemic over depressive symptoms among mothers from a population-based birth cohort in southern brazil.

PURPOSE: Our aim was to assess the impact of COVID-19 on depressive symptoms among mothers from a population-based birth cohort in Pelotas, Southern Brazil. METHODS: A subgroup of mothers from the Pelotas 2004 Birth Cohort was assessed pre-pandemic (November,2019 to March,2020) and mid-pandemic (August-December,2021). In both follow-ups, depressive symptoms were assessed using the Edinburgh Postnatal Depression Scale (EPDS). Pre-pandemic (T1) and pandemic-related predictors (T2) were analyzed. Prevalence of depression (EPDS score ≥ 13) at T1 and T2 were compared with chi-square test. Changes in EPDS from T1 to T2 were estimated by multivariate latent change score modelling. RESULTS: 1,550 women were assessed. Prevalence of depression increased 38.1% (from 18.9% at T1 to 26.1% at T2) (p < 0.001). At T1, higher schooling, higher family income and being employed or working were related to lower EPDS, whereas being beneficiary of a cash transfer program and a larger number of people living in the household predicted higher EPDS. The deterioration of ones' own perception of quality of overall health (ß = 0.191; SE = 0.028; p < 0.001) and worst family financial situation due to the pandemic (ß = 0.083; SE = 0.024; p = 0.001) predicted the increase in EPDS from T1 to T2. CONCLUSION: Almost two years after the beginning of the pandemic, the prevalence of depressive symptoms among the women was higher than before the pandemic. The deterioration of ones' own perception of quality of overall health and worst family financial situation due to the pandemic are proxies for the effect of COVID-19 pandemic (the true exposure of interest) in the women mental health.

Contextual, maternal, and infant factors in preventable infant deaths: a statewide ecological and cross-sectional study in Rio Grande do SUL, Brazil.

BACKGROUND: Ending preventable deaths of newborns and children under five by 2030 is among the United Nations Sustainable Development Goals. This study aimed to describe infant mortality rate due to preventable causes in Rio Grande do Sul (RS), the Southernmost state in Brazil. With 11,329,605 inhabitants and 141,568 live births in 2017, RS was the fifth most populous state in the country. METHOD: An ecological and cross-sectional statewide study, with data extracted from records of the Mortality Information System, Death Certificates, and Live Birth Certificates for the year 2017. Preventability was estimated by applying the List of Causes of Deaths Preventable through Intervention of SUS (acronym for Sistema Unico de Saude - Brazilian Unified Health System) Intervention. Rates of preventable infant mortality (PIMR), preventable early neonatal mortality (PENMR), preventable late neonatal mortality (PLNMR), and preventable post-neonatal mortality (PPNMR) per 1000 live births (LB) were quantified. Incidence ratios, according to contextual characteristics (human development index of the health region and of the municipality; Gini index of the municipality), maternal characteristics at the time of delivery (age, education, self-reported skin color, presence of a partner, number of antenatal care consultations, and type of delivery), and characteristics of the child at the time of birth (gestational age, weight, and pregnancy type) were calculated. RESULTS: In 2017, there were 141,568 live births and 1425 deaths of infants younger than 1 year old, of which 1119 were preventable (PIMR = 7.9:1000 LB). The PENMR, PLNMR, and PPNMR were 4.1:1000 LB; 1.5:1000 LB; and 2.3:1000 LB, respectively. More than 60% of deaths in the first week and 57.5% in the late neonatal period could be reduced through adequate care of the woman during pregnancy. The most frequent preventable neonatal causes were related to prematurity, mainly acute respiratory syndrome, and non-specified bacterial septicemia. In the post-neonatal period, 31.8% of deaths could be prevented through adequate diagnostic and treatment. CONCLUSIONS: The strategies needed to reduce preventable infant deaths should preferably focus on preventing prematurity, through adequate care of the woman during pregnancy.

Maternal depression trajectories in childhood, subsequent maltreatment, and adolescent emotion regulation and self-esteem: the 2004 Pelotas birth cohort.

This study aimed to examine the impact of maternal depressive symptoms trajectories on 15-year-old adolescents' self-esteem and emotion regulation and test the mediating role of child maltreatment in this association. The 2004 Pelotas Birth Cohort is an ongoing cohort study originally comprised of 4231 live births in a southern Brazilian city. We examined a subsample of 1949 adolescents at age 15 years. Maternal depressive symptoms were assessed using the Edinburgh Postnatal Depression Scale. Trajectories of maternal depression from 3 months until the 11-year follow-up were calculated using a group-based modeling approach. Child maltreatment at age 11 years was measured using the parent-report version of the Parent-Child Conflict Tactics Scale. Adolescent outcomes at age 15 years were assessed by the self-report version of the Rosenberg Self-esteem Scale and the Emotion Regulation Index for Children and Adolescents. Path model analysis was conducted using a structural equation modeling framework in Mplus software. All maternal depression trajectories were negatively associated with offspring self-esteem and emotion regulation compared to the reference group (low depression trajectory). There was a significant indirect effect of maternal depression trajectories on emotion regulation mediated via child maltreatment. No evidence of moderation by sex was found for any pathway. The effects of maternal depression on adolescents' emotion regulation are partly mediated by child maltreatment at age 11.

Association between preterm infant size at 1 year and ADHD later in life: data from 1993 and 2004 Pelotas Birth Cohorts.

The objective of this study is to examine the association between preterm infants' size at 1 year and attention-deficit/hyperactivity disorder (ADHD) assessed categorically and dimensionally in childhood and adolescence. We studied infants born < 37 weeks' gestation from two Brazilian birth cohorts (n = 653). ADHD was evaluated using the Development and Well-Being Assessment (DAWBA) interview at the age of 6 years in one cohort and by a structured interview according to DSM-5 criteria at 18 years in the other one. The presence of child attention difficulties was measured by the Strengths and Difficulties Questionnaire (SDQ) at 6 and 11 years in the 2004 and 1993 cohorts, respectively. We estimated associations of weight, length, head circumference, and BMI z-scores at 1-year chronological age with ADHD using Poisson Regression Model; and with attention difficulties using Linear Regression, adjusting for covariates. Mean birth weight was 2500 g and gestational age was 34.5 weeks. The aggregated ADHD prevalence in the two cohorts was 2.7%, and the median score for attention difficulties was 3.0. We found that increased head circumference at 1 year was associated with a lower risk of ADHD diagnosis (RR = 0.7, 95% CI 0.4, 0.9; p = 0.04 per standard deviation difference) and with fewer dimensional attention symptoms. In sensitivity analysis with other mental disorders, head circumference was associated with depression, but not with anxiety. Our findings emphasize poor head growth in the first year of life as a potential determinant of attentional difficulties in the preterm infant population.

Construction and validation of the Oxford Neurodevelopment Assessment (OX-NDA) in 1-year-old Brazilian children.

BACKGROUND: Over 250 million children under 5 years, globally, are at risk of developmental delay. Interventions during the first 2 years of life have enduring positive effects if children at risk are identified, using standardized assessments, within this window. However, identifying developmental delay during infancy is challenging and there are limited infant development assessments suitable for use in low- and middle-income (LMIC) settings. Here, we describe a new tool, the Oxford Neurodevelopment Assessment (OX-NDA), measuring cognition, language, motor, and behaviour, outcomes in 1-year-old children. We present the results of its evaluation against the Bayley Scales of Infant Development IIIrd edition (BSID-III) and its psychometric properties. METHODS: Sixteen international tools measuring infant development were analysed to inform the OX-NDA's construction. Its agreement with the BSID-III, for cognitive, motor and language domains, was evaluated using intra-class correlations (ICCs, for absolute agreement), Bland-Altman analyses (for bias and limits of agreement), and sensitivity and specificity analyses (for accuracy) in 104 Brazilian children, aged 12 months (SD 8.4 days), recruited from the 2015 Pelotas Birth Cohort Study. Behaviour was not evaluated, as the BSID-III's adaptive behaviour scale was not included in the cohort's protocol. Cohen's kappas and Cronbach's alphas were calculated to determine the OX-NDA's reliability and internal consistency respectively. RESULTS: Agreement was moderate for cognition and motor outcomes (ICCs 0.63 and 0.68, p < 0.001) and low for language outcomes (ICC 0.30, p < 0.04). Bland-Altman analysis showed little to no bias between measures across domains. The OX-NDA's sensitivity and specificity for predicting moderate-to-severe delay on the BSID-III was 76, 73 and 43% and 75, 80 and 33% for cognition, motor and language outcomes, respectively. Inter-rater (k = 0.80-0.96) and test-rest (k = 0.85-0.94) reliability was high for all domains. Administration time was < 20 minutes. CONCLUSION: The OX-NDA shows moderate agreement with the BSID-III for identifying infants at risk of cognitive and motor delay; agreement was low for language delay. It is a rapid, low-cost assessment constructed specifically for use in LMIC populations. Further work is needed to evaluate its use (i) across domains in populations beyond Brazil and (ii) to identify language delays in Brazilian children.

Harsh parenting and child conduct and emotional problems: parent- and child-effects in the 2004 Pelotas Birth Cohort.

In high-income countries, links between harsh and abusive parenting and child conduct and emotional problems are well-documented. However, less is known about these relationships in low- and middle-income countries, where harsh parenting may be more widely accepted and higher rates of conduct or emotional problems may exist which could influence the strength of these associations. We sought to investigate these relationships in a large population-based, prospective longitudinal study from Brazil, which also allowed us to test for sex differences. Using data from the 2004 Pelotas Birth Cohort Study (N = 4231) at ages 6 and 11 years, we applied cross-lagged path analysis to examine the relationships between harsh parenting (Conflict Tactics Scale Parent-Child version), and child conduct and emotional problems (Strengths and Difficulties Questionnaire). We found reciprocal relationships between harsh parenting and child conduct problems, with harsh parenting at age 6 predicting child conduct problems at age 11, and vice versa, even after adjusting for initial levels of conduct problems and harsh parenting, respectively. For child emotional problems, only unidirectional effects were found, with harsh parenting at age 6 predicting child emotional problems at age 11, after adjusting for initial levels of emotional problems, but not vice versa. No significant sex differences were observed in these relationships. These observations based on a middle-income country birth cohort highlight the potential universality of detrimental effects of harsh parenting on child conduct and emotional problems and affirm the importance of addressing parent- and child-effects in preventive and treatment interventions, especially those targeting conduct problems.

Effect of Correcting the Postnatal Age of Preterm-Born Children on Measures of Associations Between Infant Length-for-Age z Scores and Mid-Childhood Outcomes.

Child growth standards are commonly used to derive age- and sex-standardized anthropometric indices but are often inappropriately applied to preterm-born children (<37 weeks of gestational age (GA)) in epidemiology studies. Using the 2004 Pelotas Birth Cohort, we examined the impact of correcting for GA in the application of child growth standards on the magnitude and direction of associations in 2 a priori-selected exposure-outcome scenarios: infant length-for-age z score (LAZ) and mid-childhood body mass index (scenario A), and infant LAZ and mid-childhood intelligence quotient (scenario B). GA was a confounder that had a strong (scenario A) or weak (scenario B) association with the outcome. Compared with uncorrected postnatal age, using GA-corrected postnatal age attenuated the magnitude of associations, particularly in early infancy, and changed inferences for associations at birth. Although differences in the magnitude of associations were small when GA was weakly associated with the outcome, model fit was meaningfully improved using corrected postnatal age. When estimating population-averaged associations with early childhood growth in studies where preterm- and term-born children are included, incorporating heterogeneity in GA at birth in the age scale used to standardize anthropometric indices postnatally provides a useful strategy to reduce standardization errors.

Maternal perinatal depression and infant sleep problems at 1 year of age: Subjective and actigraphy data from a population-based birth cohort study.

This study used data from 2,222 mothers and infants participating in a population-based birth cohort to verify whether maternal depression in the perinatal period was associated with poor infant sleep. Mothers who scored ≥13 points on the Edinburgh Postnatal Depression Scale at 16-24 weeks of gestation and/or 3 months after delivery were considered perinatally depressed. The main outcome variable was poor infant sleep at 12 months of age, defined as >3 night wakings, nocturnal wakefulness >1 hr or total sleep duration <9 hr. Infant sleep data were obtained with the Brief Infant Sleep Questionnaire (BISQ) and 24-hr actigraphy monitoring. Prevalence of perinatal depression in the sample was 22.3% (95% confidence interval [CI], 20.5-24.0). After Poisson regression, infants of depressed mothers showed an adjusted relative risk (RR) of 1.44 (95% CI, 1.00-2.08; p = .04) for >3 night wakings with questionnaire-derived data. When actigraphy data were analysed, no association was found between perinatal depression and poor infant sleep (adjusted RR, 1.20; 95% CI, 0.82-1.74; p = .35). In conclusion, although mothers in the depressed group were more likely to report more night wakings, objective data from actigraphy did not replicate this finding. Dysfunctional cognition, maternal behavioural factors and sleep impairment associated with perinatal depression may affect the mother's impression of her infant's sleep.

All day-long pacifier use and intelligence quotient in childhood: A birth cohort study.

BACKGROUND: Literature on pacifier use remains controversial, but mostly suggests an inverse association with childhood intelligence. OBJECTIVES: The objective of this study was to assess the association between pacifier use and intelligence quotient (IQ) in six-year-old children from a birth cohort. METHODS: Data from 3532 children from the 2004 Pelotas (Brazil) Birth Cohort were analysed. Children were recruited and assessed at birth and followed up at 3 months, and 1, 2, 4, and 6 years. Data on pacifier use duration and intensity were obtained via interviews with mothers in all six follow-up visits. IQ was estimated at 6 years using the Wechsler Intelligence Scale for Children and standardised for the analyses. Crude and adjusted coefficients were calculated (linear regression) for all the data collected in follow-up assessments for pacifier use. RESULTS: IQ was inversely associated with all pacifier use indicators. Children who used a pacifier all day long (ADL) at any follow-up showed an IQ 0.18 (95% confidence interval [CI] 0.11, 0.24) standard deviations below those who never used it ADL, after adjusting for confounders. The strength of association increased with number of assessments reporting ADL pacifier use, from a reduction in IQ of 0.13 (95% CI 0.06, 0.21) to 0.34 (95% CI 0.15, 0.52) standard deviations for ADL use in one and in all four follow-up visits, respectively. CONCLUSIONS: We found a strong association between intense pacifier use up to 4 years of age and lower IQ at 6 years. A dose-response gradient was observed, with greater IQ deficits in children who used a ADL pacifier for longer durations. The mechanisms underlying this association need to be clarified. One hypothesis is that children using a pacifier, especially those who use it more intensely, are less stimulated.

Trajectories of maternal depressive symptoms and offspring's risk behavior in early adolescence: data from the 2004 Pelotas birth cohort study.

BACKGROUND: This longitudinal study explored the relationship between trajectories of maternal depressive symptoms and offspring's risk behavior in adolescence contributing to an extremely scarce literature about the impacts of maternal depression trajectories on offspring risk behaviors. METHODS: We included 3437 11-year-old adolescents from the 2004 Pelotas Birth Cohort Study. Trajectories of maternal depressive symptoms were constructed using Edinburgh Postnatal Depression Scale (EDPS) from age 3 months to 11 years. We identified five trajectories of maternal depressive symptoms: "low" "moderate low", "increasing", "decreasing", and "chronic high". The following adolescent outcomes were identified via self-report questionnaire and analyzed as binary outcome -yes/no: involvement in fights and alcohol use at age 11. We used logistic regression models to examine the effects of trajectories of maternal depressive symptoms on offspring's risk behavior adjusting for potential confounding variable. RESULTS: Alcohol use and/or abuse as well as involvement in fights during adolescence, were not significantly associated with any specific trajectory of maternal depressive symptoms neither in the crude nor in the adjusted analyses. CONCLUSION: Alcohol use and involvement in fights at age 11 were not associated with any specific trajectory of maternal depression.

Consumption of ultra-processed foods at 11, 22 and 30 years at the 2004, 1993 and 1982 Pelotas Birth Cohorts.

OBJECTIVE: To describe the consumption of ultra-processed foods according to demographic and socioeconomic characteristics in three birth cohorts. DESIGN: Cross-sectional analysis. SETTING: Data from the 2004, 1993 and 1982 Pelotas Birth Cohorts were used at 11, 22 and 30 years, respectively, collected between 2012 and 2015. Outcome was the relative contribution of ultra-processed foods from the total daily energy intake. Maternal-independent variables were self-reported skin colour, schooling, age and family income (obtained in the perinatal study), and variables of the cohort member, sex, skin colour, schooling and current family income (the last two obtained at the 11-, 22- and 30-year follow-ups of the respective cohorts). We calculated crude and adjusted means of the outcome for the whole cohorts and according to the independent variables. PARTICIPANTS: 11-, 22- and 30-year-old individuals. RESULTS: Daily energetic contribution from ultra-processed foods was higher in the younger cohort (33·7, 29·8 and 25·1 % at 11, 22 and 30 years, respectively). Maternal schooling and family income at birth showed an inverse dose-response relationship at 11 and 22 years, but a positive dose-response at 30 years. Female sex, lower schooling and family income at 22 years and higher schooling at 30 years were associated to a higher contribution from ultra-processed foods in the daily energy intake. CONCLUSIONS: Information from food and nutrition policies needs a higher dissemination, mostly among women and population groups of lower income and schooling, including its promotion in media and health services, aiming for a decreased consumption of ultra-processed foods.

Influence of maternal pre-pregnancy nutritional status on offspring anthropometric measurements and body composition in three Brazilian Birth Cohorts.

OBJECTIVE: We aimed at evaluating the association of maternal pre-pregnancy nutritional status with offspring anthropometry and body composition. We also evaluated whether these associations were modified by gender, diet and physical activity and mediated by birth weight. DESIGN: Birth cohort study. SETTING: Waist circumference was measured with an inextensible tape, and fat and lean mass were measured using dual-energy X-ray absorptiometry. Multiple linear regression was used to adjust for possible confounders and allele score of BMI. We carried out mediation analysis using G-formula. PARTICIPANTS: In 1982, 1993 and 2004, all maternity hospitals in Pelotas (South Brazil) were visited daily and all live births whose families lived in the urban area of the city were evaluated. These subjects have been followed up at different ages. RESULTS: Offspring of obese mothers had on average higher BMI, waist circumference and fat mass index than those of normal weight mothers, and these differences were higher among daughters. The magnitudes of the association were similar in the cohorts, except for height, where the association pattern was not clear. In the 1982 cohort, further adjustment for a BMI allele score had no material influence on the magnitude of the associations. Mediation analyses showed that birth weight captured part of this association. CONCLUSIONS: Our findings suggest that maternal pre-pregnancy nutritional status is positively associated with offspring BMI and adiposity in offspring. And this association is higher among daughters whose mother was overweight or obese and, birth weight explains part of this association.

Prematurity and body composition at 6, 18, and 30 years of age: Pelotas (Brazil) 2004, 1993, and 1982 birth cohorts.

BACKGROUND: We aimed to investigate the association between preterm birth and body composition at 6, 18, and 30 years of age using data from three population-based birth cohort studies. METHODS: Gestational age (GA), defined by the date of the last menstrual period (categorized in ≤33, 34-36, and ≥ 37 weeks), was gathered in the first 24-h after delivery for all live births occurring in the city of Pelotas, Brazil, in 2004, 1993 and 1982. Body composition was assessed by air-displacement plethysmography. Outcomes included fat mass (FM, kg), percent FM (%FM), FM index (FMI, kg/m2), fat-free mass (FFM, kg); percent FFM (%FFM), FFM index (FFMI, kg/m2), body mass index (BMI, kg/m2 at 18 years in the 1993 cohort and 30 years in the 1982 cohort), and BMI Z-score (at 6 years in the 2004 cohort). We further explored the association of birth weight for GA with body composition indicators and BMI. Crude and adjusted linear regressions provided beta coefficients with 95% confidence intervals (95%CI). RESULTS: A total of 3036, 3027, and 3369 participants, respectively, from the 2004, 1993, and 1982 cohorts were analyzed. At 6 years, preterm boys (born at 34-36 weeks) presented lower adjusted mean of FM (ß = - 0.80 kg, - 1.45;-0.16, p = 0.046), %FM (ß = - 2.39%, - 3.90;-0.88, p = 0.008), FMI (ß = - 0.70 kg/m2, - 1.13;-0.27, p = 0.004) as well as lower FFM (ß = - 0.4 kg, - 0.77; - 0.12, p = 0.010) and FFMI (ß = - 0.3 kg/m2, - 0.46;-0.10, p < 0.001), and BMI Z-score (ß = - 0.69,; - 0.99;-0.40, p < 0.001); but higher %FFM (ß = 2.4%, 0.87;-3.90, p = 0.008), when compared to boys born at term (≥37). At 30 years, FM (15.7 kg, 0.25;31.1, p = 0.102) was higher among males born at ≤33 weeks. No association was observed for females from the three cohorts and for 18-year-old males. The association of birth weight for GA with body composition and BMI was not significant in any cohort. At 6 years, SGA boys had lower FFMI than boys AGA. CONCLUSIONS: Our results suggest that preterm birth is associated with decreased body fat and fat-free mass in childhood but higher fat mass in adulthood. Nevertheless, results were only significant for males. SGA boys also showed lower FFMI.