Population-based Birth Cohort Study Research Articles

Self-reported and Agency-Notified Child Abuse as a Contributor to Health Anxiety in a Population-Based Birth Cohort Study at 30-Year Follow-up.

Health anxiety is a subtype of the older term hypochondriasis, in which there is worry rather than conviction of having an illness. Information on the association between childhood maltreatment and health anxiety in adulthood often comes from retrospective questionnaires that may be subject to recall bias. There are no prospective data studies using reports to statutory agencies. We therefore assessed the effect on these outcomes at 30-year follow-up using both prospective agency notifications of child abuse and retrospective self-reports in the same birth cohort. At follow-up, there were 2458 adults with data on health anxiety as measured by the Whiteley Index. We also collected details on self-reported abuse with the Child Trauma Questionnaire and linked this to child maltreatment notifications to statutory agencies. The prevalence of self- and agency-reported maltreatment was 600 (24.4%) and 143 (5.8%), respectively. Of the participants, 235 were in the top 10% of Whiteley Index scores. On adjusted analyses, self-reported maltreatment of all types showed significant associations with increased health anxiety, while this was limited to sexual abuse in the case of agency-reported childhood maltreatment (adjusted odds ratio=2.17; 95% confidence interval=1.06-4.46; P=0.034). Effects were strongest in women. Both self- and agency-reported childhood maltreatment showed a significant association with somatic symptoms in adulthood although patterns were different and of varying degrees.

The association between prenatal greenspace exposure and Autism spectrum disorder, and the potentially mediating role of air pollution reduction: A population-based birth cohort study.

Autism spectrum disorder (ASD) incidence has increased in past decades. ASD etiology remains inconclusive, but research suggests genetic, epigenetic, and environmental contributing factors and likely prenatal origins. Few studies have examined modifiable environmental risk factors for ASD, and far fewer have examined protective exposures. Greenspace has been associated with positive child development, but very limited greenspace research has examined ASD risk or prenatal exposures. Only one ecological study in 2017 has evaluated the association between greenspace and ASD, observing protective benefits. Greenspace may have direct effects on ASD risk and indirect effects by reducing air pollution exposure, a growing suspected ASD risk factor. To measure the association between prenatal greenspace exposure and ASD risk and examine if reduced air pollution levels in areas of higher greenspace mediate this association. We linked a population-based birth cohort of all deliveries in Metro Vancouver, Canada, from 2004 to 2009, with follow-up to 2014. Diagnoses were based on Autism Diagnostic Observation Schedule and Autism Diagnostic Interview-Revised instruments. Greenspace was quantified as the average of the annual mean Normalized Difference Vegetation Index (NDVI) within a 250m buffer of a residential postal code. Air pollutant exposures-particulate matter with a diameter less than 2.5µm (PM2.5), nitric oxide (NO), and nitrogen dioxide (NO2)-were derived from previously developed and temporally adjusted land use regression models. We estimated air pollutant exposures as the mean concentration per month during pregnancy. We calculated odds ratios (ORs) using logistic regression per NDVI interquartile range (IQR) increase, adjusting for child sex, birth month and year, maternal age and birthplace, and neighborhood-level urbanicity and income. To estimate the health impact of greenspace on ASD at the population level, we used the logistic regression model and marginal standardization to derive risk differences (RDs). Lastly, to quantify the mediating effect of greenspace on ASD risk through air pollution reduction, we used marginal structural models and a potential outcomes framework to calculate marginal risk differences (RDs) to decompose the total effect of greenspace on ASD into natural direct and indirect effects. Of 129,222 births, 1,921 (1.5%) children were diagnosed with ASD. The adjusted OR for ASD per NDVI IQR (0.12) increase was 0.96 (95% CI: 0.90, 1.02) in 250m buffer zones and 0.94 (95% CI: 0.89, 1.00) in 100m buffer zones. On the additive scale, the adjusted RDs were null. Natural direct, natural indirect, and total effect RDs were null for PM2.5, NO, and NO2 mediation models. Prenatal greenspace exposure was associated with reduced odds of ASD, but in the additive scale, this effect was null at the population level. No mediating effect was observed through reduced air pollution, suggesting that air pollution may act as a confounder rather than as a mediator.

Associations between pre- and postnatal antibiotic exposures and early allergic outcomes: A population-based birth cohort study.

BackgroundEarly life antibiotic treatment is one likely exposure influencing allergy risk. The objective was to investigate associations between pre‐ and postnatal antibiotic exposures and the development of allergic manifestations until age 18 months.MethodsWe included 1387 mother–child dyads from the prospective, population‐based NorthPop birth cohort study. Data on antibiotic exposures in pregnancy and childhood were collected by web‐based questionnaires. Until the child turned 18 months old, parents (n = 1219) reported symptoms of wheeze, eczema, and physician‐diagnosed asthma; parents (n = 1025) reported physician‐diagnosed food allergy. At age 18 months, serum immunoglobulin E levels to inhalant (Phadiatop) and food (Food mix fx5) allergens were determined. Associations were estimated using bivariable and multivariable logistic regressions.ResultsPrenatal antibiotic exposure was positively associated with food sensitization in the crude (OR 1.82, 95% CI 1.01–3.26) but not in the adjusted analyses (aOR 1.58, 0.82–3.05). A borderline significant association was found between prenatal exposure and wheeze (aOR 1.56, 0.95–2.57). Postnatal antibiotics were positively associated with wheeze (aOR 2.14, 1.47–3.11), asthma (aOR 2.35, 1.32–4.19), and eczema (aOR 1.49, 1.07–2.06). Postnatal antibiotics were negatively associated with food sensitization (aOR 0.46, 95% CI 0.25–0.83) but not with food allergy nor sensitization to inhalants.ConclusionPre‐ and postnatal antibiotic exposure demonstrated positive associations with allergic manifestations and the former also with food sensitization. In contrast, there was a negative association between postnatal antibiotics and food sensitization. Food sensitization is often transient but may precede respiratory allergies. Future studies should investigate the relationship between antibiotic exposure and food sensitization later in childhood.

The association between maternal ultra-processed food consumption during pregnancy and child neuropsychological development: A population-based birth cohort study

Maternal ultra-processed food (UPF) consumption during pregnancy may adversely affect child development. Pregnancy sugar-sweetened beverage consumption (as a part of UPF) has been associated with child cognitive dysfunction in the general population, but the role of total UPF consumption during pregnancy in later child neuropsychological development has not been studied. We aimed to analyse the association between maternal pregnancy UPF consumption and child neurodevelopment. This study involved 2377 pairs of pregnant women and their offspring from a Spanish birth cohort (recruitment period: 2004-2008, INMA project). Dietary intake was estimated using a 101-item food frequency questionnaire in the third trimester of pregnancy. The NOVA classification was used to identify UPFs, and their consumption was calculated as the daily percentage of total food consumption and categorized into tertiles. Child neuropsychological development was assessed with the Bayley Scales of Infant and Toddler Development (1-year-old, n=1929) and the McCarthy Scales of Children's Abilities (4-5 years-old, n=1679). Potential associations were analysed using multivariate linear regression models adjusted for a range of family and child characteristics. UPF consumption among pregnant women represented an average of 17% of the total diet, with sugar-sweetened beverages being the most commonly consumed type of UPF (40%). Children born to mothers in the highest tertile of UPF consumption (28.9% or more of the total diet) vs the lowest tertile (7.2% or less), showed a lower score (B=-2.29 [95% Confidence Interval (CI),-4.13;-0.46]) in the Verbal Scale of the McCarthy Scales (p-for-trend=0.02). No associations were observed with the McCarthy Scales assessing other cognitive domains or with the Bayley Scales. Of the seven cognitive domains studied, we observed an adverse association between maternal consumption of UPF during pregnancy and verbal functioning in early childhood, which is an important cognitive domain of neurodevelopment.

Prenatal Exposure to Mercury, Manganese, and Lead and Adverse Birth Outcomes in Suriname: A Population-Based Birth Cohort Study.

Globally, adverse birth outcomes are increasingly linked to prenatal exposure to environmental contaminants, such as mercury, manganese, and lead. This study aims to assess an association between prenatal exposure to mercury, manganese, and lead and the occurrence of adverse birth outcomes in 380 pregnant women in Suriname. The numbers of stillbirths, preterm births, low birth weights, and low Apgar scores were determined, as well as blood levels of mercury, manganese, lead, and relevant covariates. Descriptive statistics were calculated using frequency distributions. The associations between mercury, manganese, and lead blood levels, on the one hand, and adverse birth outcomes, on the other hand, were explored using contingency tables, tested with the χ2-test (Fisher’s exact test), and expressed with a p value. Multivariate logistic regression models were computed to explore independent associations and expressed as (adjusted) odds ratios (aOR) with 95% confidence intervals (CI). The findings of this study indicate no statistically significant relationship between blood mercury, manganese, or lead levels and stillbirth, preterm birth, low birth weight, and low Apgar score. However, the covariate diabetes mellitus (aOR 5.58, 95% CI (1.38–22.53)) was independently associated with preterm birth and the covariate hypertension (aOR 2.72, 95% CI (1.081–6.86)) with low birth weight. Nevertheless, the observed high proportions of pregnant women with blood levels of mercury, manganese, and lead above the reference levels values of public health concern warrants environmental health research on risk factors for adverse birth outcomes to develop public health policy interventions to protect pregnant Surinamese women and their newborns from potential long-term effects.

Associations of Gestational Weight Gain with Perinatal Outcomes in Western Brazilian Amazon

To investigate the association between gestational weight gain (GWG) and perinatal outcomes in pregnant Amazonian women. Data from 1305 mother-child pairs from the MINA-Brazil population-based birth cohort study were used. GWG was classified according to two methods, the Institute of Medicine (IOM) guidelines and INTERGROWTH-21st standards. Poisson and linear regression analyses were conducted to evaluate associations with perinatal outcomes. Following IOM guidelines (n = 1305), the rates of insufficient and excessive GWG were found to be similar (32%). Excessive GWG was associated with higher new-born birthweight (BW) z-scores; increased risks of macrosomia, large for gestational age (LGA), and caesarean delivery; and lower risks of low birthweight (LBW) and being small for gestational age (SGA). Insufficient GWG was associated with lower new-born BW z-scores. Among women with normal pre-pregnancy body mass indices (BMIs, n = 658), inappropriate GWG was high following both methods (IOM: 41.2% insufficient, 24.8% excessive; INTERGROWTH-21st: 25.2% below -1 z-score, 16.9% above 1 z-score). Both methods also indicated that new-borns of women with excessive GWG had higher BW z-scores and increased risk of macrosomia and LGA. Women with GWG below the INTERGROWTH-21st standards were more likely to deliver an infant SGA and with lower BW z-scores. Inappropriate GWG remains a health concern irrespective of the method used to classify weight gain. GWG above the recommendations of both methods and below the INTERGROWTH-21st standard was associated with adverse perinatal outcomes. Therefore, INTERGROWTH-21st standards seem to be a better fit for healthy women in this population.

SARS-CoV-2 seropositivity and COVID-19 among 5 years-old Amazonian children and their association with poverty and food insecurity.

The epidemiology of childhood SARS-CoV-2 infection and COVID-19-related illness remains little studied in high-transmission tropical settings, partly due to the less severe clinical manifestations typically developed by children and the limited availability of diagnostic tests. To address this knowledge gap, we investigate the prevalence and predictors of SARS-CoV-2 infection (either symptomatic or not) and disease in 5 years-old Amazonian children. We retrospectively estimated SARS-CoV-2 attack rates and the proportion of infections leading to COVID-19-related illness among 660 participants in a population-based birth cohort study in the Juruá Valley, Amazonian Brazil. Children were physically examined, tested for SARS-CoV-2 IgG and IgM antibodies, and had a comprehensive health questionnaire administered during a follow-up visit at the age of 5 years carried out in January or June-July 2021. We found serological evidence of past SARS-CoV-2 infection in 297 (45.0%; 95% confidence interval [CI], 41.2-48.9%) of 660 cohort participants, but only 15 (5.1%; 95% CI, 2.9-8.2%) seropositive children had a prior medical diagnosis of COVID-19 reported by their mothers or guardians. The period prevalence of clinically apparent COVID-19, defined as the presence of specific antibodies plus one or more clinical symptoms suggestive of COVID-19 (cough, shortness of breath, and loss of taste or smell) reported by their mothers or guardians since the pandemic onset, was estimated at 7.3% (95% CI, 5.4-9.5%). Importantly, children from the poorest households and those with less educated mothers were significantly more likely to be seropositive, after controlling for potential confounders by mixed-effects multiple Poisson regression analysis. Likewise, the period prevalence of COVID-19 was 1.8-fold (95%, CI 1.2-2.6-fold) higher among cohort participants exposed to food insecurity and 3.0-fold (95% CI, 2.8-3.5-fold) higher among those born to non-White mothers. Finally, children exposed to household and family contacts who had COVID-19 were at an increased risk of being SARS-CoV-2 seropositive and-even more markedly-of having had clinically apparent COVID-19 by the age of 5 years. Childhood SARS-CoV-2 infection and COVID-19-associated illness are substantially underdiagnosed and underreported in the Amazon. Children in the most socioeconomically vulnerable households are disproportionately affected by SARS-CoV-2 infection and disease.

Association of Prenatal Exposure to Endocrine-Disrupting Chemicals With Liver Injury in Children

Prenatal exposures to endocrine-disrupting chemicals (EDCs) may increase the risk for liver injury in children; however, human evidence is scarce, and previous studies have not considered potential EDC-mixture effects. Furthermore, the association between prenatal EDC exposure and hepatocellular apoptosis in children has not been studied previously. To investigate associations of prenatal exposure to EDC mixtures with liver injury risk and hepatocellular apoptosis in childhood. This prospective cohort study used data collected from April 1, 2003, to February 26, 2016, from mother-child pairs from the Human Early-Life Exposome project, a collaborative network of 6 ongoing, population-based prospective birth cohort studies from 6 European countries (France, Greece, Lithuania, Norway, Spain, and the UK). Data were analyzed from April 1, 2021, to January 31, 2022. Three organochlorine pesticides, 5 polychlorinated biphenyls, 2 polybrominated diphenyl ethers (PBDEs), 3 phenols, 4 parabens, 10 phthalates, 4 organophosphate pesticides, 5 perfluoroalkyl substances, and 9 metals. Child serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyltransferase (GGT), and CK-18 were measured at 6 to 11 years of age. Risk for liver injury was defined as having ALT, AST, and/or GGT levels above the 90th percentile. Associations of liver injury or cytokeratin 18 (CK-18) levels with each chemical group among the 45 EDCs measured in maternal blood or urine samples collected in pregnancy were estimated using 2 complimentary exposure-mixture methods: bayesian weighted quantile sum (BWQS) and bayesian kernel machine regression. The study included 1108 mothers (mean [SD] age at birth, 31.0 [4.7] years) and their singleton children (mean [SD] age at liver assessment, 8.2 [1.6] years; 598 [54.0%] boys). Results of the BWQS method indicated increased odds of liver injury per exposure-mixture quartile increase for organochlorine pesticides (odds ratio [OR], 1.44 [95% credible interval (CrI), 1.21-1.71]), PBDEs (OR, 1.57 [95% CrI, 1.34-1.84]), perfluoroalkyl substances (OR, 1.73 [95% CrI, 1.45-2.09]), and metals (OR, 2.21 [95% CrI, 1.65-3.02]). Decreased odds of liver injury were associated with high-molecular-weight phthalates (OR, 0.74 [95% CrI, 0.60-0.91]) and phenols (OR, 0.66 [95% CrI, 0.54-0.78]). Higher CK-18 levels were associated with a 1-quartile increase in polychlorinated biphenyls (β, 5.84 [95% CrI, 1.69-10.08] IU/L) and PBDEs (β, 6.46 [95% CrI, 3.09-9.92] IU/L). Bayesian kernel machine regression showed associations in a similar direction as BWQS for all EDCs and a nonlinear association between phenols and CK-18 levels. With a combination of 2 state-of-the-art exposure-mixture approaches, consistent evidence suggests that prenatal exposures to EDCs are associated with higher risk for liver injury and CK-18 levels and constitute a potential risk factor for pediatric nonalcoholic fatty liver disease.

Maternal parenting stress from birth to 36months, maternal depressive symptoms, and physical punishment to 10-year-old children: a population-based birth cohort study.

This study aimed to investigate the association between parenting stress, maternal depressive symptoms, and use of physical punishment when the child is 10years old. Data from the Tokyo Early Adolescence Survey on early adolescents and primary caregivers (N = 4478) were used. Frequency of using physical punishment, level of depressive symptoms (Kessler Psychological Distress Scale 6), and maternal parenting stress experienced at 1, 3, 9, 18, and 36months after birth were evaluated. Multiple linear and multinomial logistic regression analyses were conducted. Mothers (1633) who provided information on parenting stress at all the five points were included for the analysis. After controlling for the child's age, sex, birth weight, maternal age, and annual household income, presence of maternal parenting stress at every time point, except at three months after birth, was significantly associated with an increased risk of using physical punishment with the 10-year-old. After adjusting for levels of depressive symptoms, significant associations were found between use of physical punishment and maternal parenting stress at 1month (adjusted odds ratio [OR] 1.71, 95% confidence interval [Cl] 1.12-2.61) and 36months (adjusted OR 1.70, 95% CI 1.10-2.61) after birth. Maternal parenting stress experienced at 1 and 36months after birth predicted use of physical punishment, even after adjusting for maternal depressive symptoms. Maternal support should, therefore, be provided to mothers to cope with parenting stress even three years after birth to prevent the use of physical punishment in early adolescence.

Association of Preconception Blood Pressure with the Risk of Anemia in Children under Five Years of Age: A Large Longitudinal Chinese Birth Cohort.

Hypertension during pregnancy may increase the risk of anemia in the offspring. However, few studies have investigated the effects of elevated blood pressure during the preconception period on childhood anemia. This large population-based birth cohort study was performed to determine whether abnormal preconception blood pressure has long-term consequences for childhood health. Data were obtained from the China–US Collaborative Project for Neural Tube Defect Prevention. The study consisted of 40,638 women with singleton live births who were registered in a monitoring system before pregnancy in southern China during the period 1993–1996. Children were assessed by hemoglobin measurement at approximately 53 months of age. The incidences of childhood anemia were 19.80% in the hypertension group and 16.07% in the non-hypertension group. Compared with the non-hypertension group, the hypertension group had an increased risk of childhood anemia (adjusted risk ratio (RR): 1.25; 95% confidence interval (CI): 1.11–1.41). After categorization according to blood pressure, combined systolic and diastolic hypertension was associated with a significantly increased risk of childhood anemia, compared with normotension (adjusted RR: 1.37; 95% CI: 1.16–1.63). Compared with women who had normal blood pressure, the adjusted RRs for childhood anemia were 1.20 (95% CI: 1.13–1.28), 1.26 (95% CI: 1.08–1.47), and 1.38 (95% CI: 1.14–1.67) among women with prehypertension, stage-1 hypertension, and stage-2 hypertension, respectively. Our results suggest a linear association between prepregnancy hypertension and the risk of childhood anemia in the Chinese population. Interventions targeting preconception blood pressure may have a positive effect on childhood health.

Maternal socioeconomic and lifestyle factors and life dissatisfaction associated with a small for gestational age infant. The Survey of Neonates in Pomerania (SNiP)

PurposeThe aim is to investigate the associations of the mother’s socioeconomic and lifestyle factors and life satisfaction with the delivery of a small for gestational age (SGA) infant.MethodsData from 4598 participants of the population-based birth cohort study Survey of Neonates in Pomerania (SniP) including comprehensive information on pregnancies, mothers, and their offspring in Western Pomerania, Germany were used in this study. The associations were analyzed using linear and logistic regression models.ResultsAfter logistic regression analysis adjusted for height of the mother, women who delivered SGA infants, had lower education (p < 0.01) and smoked more frequently during pregnancy (p < 0.01) compared with mothers of adequate for gestational age (AGA) neonates. A mother with less than 10 years of education and one who continued smoking during pregnancy had an odds ratio (OR) of 2.23 [95% confidence interval (CI) = 1.44 to 3.46] and 2.68 (95% CI = 2.06–3.49) of having an SGA infant, respectively. There was no association between the employment of the mother (p = 0.28), the monthly income (p = 0.09), the family status (p = 0.80), the number of friendships outside the household that the mother would not wish to relinquish (p = 0.47), the number of people that she could rely on in case of an emergency (p = 0.75), or alcohol consumption prior to (p = 0.14) or during the pregnancy (p = 0.99) with SGA. Finally, women who delivered SGA infants were more frequently dissatisfied with their employment (p = 0.03) and financial status (p < 0.01).ConclusionsWomen who delivered SGA infants had more associated socioeconomic and lifestyle risk factors and were more frequently dissatisfied with their life conditions than mothers of AGA neonates.

Effect of maternal ozone exposure before and during pregnancy on wheezing risk in offspring: A birth cohort study in Guangzhou, China

Ozone (O3) exposure may lead to the development and exacerbation of asthma or wheezing in postnatal children; however, it has rarely been studied before and during pregnancy. Wheezing is one of the most common symptoms when diagnosing of asthma; thus, we investigated the associations of O3 exposure before and during pregnancy with wheezing in preschool children and the potential susceptible exposure windows from a heavily polluted city in China. This population-based birth cohort study, which included 3725 mother-child pairs from Guangzhou, began in 2016, and the follow-up period ended on July 31, 2020. We used a spatiotemporal land-use-regression model combined with activity patterns to estimate the daily O3 exposure levels during the pre-pregnancy period and each trimester, and wheezing was recorded by reviewing medical records. We used the Cox proportional hazard model to quantify the effects of O3 exposure on childhood wheezing adjusted for potential confounders. No significant association was detected between pre-pregnancy exposure to O3 and childhood wheezing. However, increased ambient O3 exposures throughout pregnancy and in the second trimester were positively associated with the risk of childhood wheezing, with hazard ratios (HRs) and 95% confident intervals (CIs) per interquartile range (IQR) increment of 1.22 (95% CI: 1.04–1.44) and 1.31 (95% CI: 1.09–1.58), respectively. The effects of maternal O3 exposure on childhood wheezing risk was stronger when the exposure occurred in the warm conception season (P < 0.05). Significant childhood wheezing risk could be attributable to maternal O3 exposure, especially during the second trimester and with warm-season conception in Guangzhou. Further cohorts of children, particularly school age children who have more robust asthma diagnoses, should be investigated in the future.

Self-Reported Maternal Parenting Stress From 9 m Is Longitudinally Associated With Child ADHD Symptoms at Age 12: Findings From a Population-Based Birth Cohort Study.

BackgroundAttention-deficit/hyperactivity disorder (ADHD) develops in early childhood and carries lifelong impact, but early identification and intervention ensure optimal clinical outcomes. Prolonged or excessive parenting stress may be a response to infant behavioral differences antecedent to developmental disorders such as ADHD, and therefore represents a potentially valuable inclusion in routine early-life assessment. To investigate the feasibility of using routinely-collected self-reported maternal parenting stress as a risk marker for child ADHD, this study investigated the longitudinal association between maternal parenting stress from 1 to 36 months after childbirth and child ADHD in early adolescence.MethodsThe sample comprised 2,638 children (1,253 girls) from the Tokyo Teen Cohort population-based birth cohort study. Mothers recorded parenting stress five times from 1 to 36 months following childbirth in the Maternal and Child Health Handbook, a tool used for routine early-life assessment in Japan. Nine years later, mothers evaluated their child's ADHD symptoms at 12 y using the hyperactivity/inattention subscale from the Strength and Difficulties Questionnaire.ResultsApproximately 7.5% of parents reported that they had parenting stress at 36 m after childbirth. 6.2% of children were evaluated as above the cut-off for ADHD symptoms at 12 y. Parenting stress at 1 and 3–4 m was not associated with child ADHD symptoms at 12 y. However, child ADHD symptoms at 12 y was significantly associated with parenting stress at 9–10 m (unadjusted OR = 1.42, p =.047, 95% CI [1.00, 2/00]), 18 m (unadjusted OR = 1.57, p =.007, 95% CI [1.13, 2.19]) and 36 m (unadjusted OR = 1.67, p =.002, 95% CI [1.20, 2.31]). These associations remained after adjustment for child's sex, age in months and family income.ConclusionsWe identified associations between parenting stress at 9–10, 18 and 36 m after childbirth and child ADHD symptoms at 12 years old. Self-reported parenting stress data may have utility as an early indicator for ADHD risk. Participation in early-life health checks, assessment of parenting stress, and tailoring support to family needs should be promoted for early identification and intervention for ADHD.

Bullying at 8 years and violent offenses by 31 years: the Finnish nationwide 1981 birth cohort study

This study explored the associations between bullying perpetration and victimization at 8 years of age and violent offenses by the age of 31. Data were obtained for subjects enrolled in a population-based longitudinal birth cohort study. In 1989, 5813 8-year-old children (attrition 3.4%), and their parents and teachers, were surveyed about bullying. When 5405 subjects (attrition 10.2%) were 15–31 years of age, violent offenses were extracted from the Finnish National Police Register. We analyzed the data by sex and categorized bullying perpetration and victimization by frequency. Violent offenses were categorized by severity. Cox regression analyses estimated the hazard ratios (HRs) and 95% confidence intervals (95% CIs). When they were compared to males who had not been bullies at 8 years of age, frequent male bullies had an increased hazard for violent offenses (adjusted HR 3.01, 95% CI 2.11–4.33) and severe violent offenses (adjusted HR 2.86, 95% CI 1.07–7.59) as adults, even when the data were controlled for them being victims, parental education level, family structure and child psychopathology. Frequent female bullies also had an increased hazard for violent offenses, compared to those who had not bullied others (adjusted HR 5.27, 95% CI 1.51–18.40). Frequent male bullying was associated with higher odds for violent offenses compared to only bullying sometimes. Being a victim was not associated with violent offenses. Preventing childhood bullying could reduce violent offenses by both sexes.

Contribution of pharmaceutical drugs of dependence to the incidence of neonatal abstinence syndrome in Western Australia between 2003 and 2018.

Study objectiveThe aim of this study was to examine the incidence of neonatal abstinence syndrome (NAS) in Western Australia (WA) and estimate the contribution of pharmaceutical drugs of dependence (PDD) to NAS.DesignA population‐based birth cohort study.Data sourceNeonates were identified through the Midwives Notification Scheme. Linked medication dispensing and hospital records were used to identify exposure to PDD and NAS diagnosis.PatientsAll live born neonates born in WA between 2003 and 2018.MeasurementsThe incidence of NAS and percentage of NAS diagnoses associated with exposure to PDD.Main resultsDuring the study period, the incidence of NAS did not significantly change (annual percentage change (APC): 0.6, 95%CI: −1.3, 2.6), with 3.8 neonates per 1,000 live births diagnosed with NAS. PDD were dispensed to 41.4% of mothers of neonates with NAS, with PDD used to treat opioid use disorders the most commonly prescribed (35.2% of neonates with NAS), while opioid PDD used in the treatment of pain contributed to 5.2% of NAS cases. Non‐opioid PDD contributed to 1.7% of cases of NAS. The incidence of NAS associated with the use of opioids used to treat opioid use disorders (OUD) decreased over the study period (APC: −6.5, 95%CI: −9.5, −3.4), while NAS associated with opioids used to treat pain remained stable (APC: −2.7, 95%CI: −7.1, 1.9).ConclusionThe incidence of neonatal abstinence syndrome in WA remained stable from 2003 to 2018. Medications used to treat opioid use disorders were a substantial driver of NAS, although NAS associated with these medications has declined over time.

Group-based trajectories of maternal intake of sugar-sweetened beverage and offspring oral health from a prospective birth cohort study

ObjectivesTo investigate the trajectory of maternal intake of sugar-sweetened beverages (SSB) during the first five years of their child's life and its effect on the child's dental caries at five years-of-age. MethodsThis is an ongoing prospective population-based birth cohort study in Adelaide, Australia. Mothers completed questionnaires on their SSB intake, socioeconomic factors and health behaviors at the birth of their child and at the ages of one, two and five years. Child dental caries measured as decayed, missing, or filled tooth surfaces was collected by oral examination. Maternal SSB intake was used to estimate the trajectory of SSB intake. The trajectories then became the main exposure of the study. Dental caries at age five years were the primary outcomes. Adjusted mean- and prevalence-ratios were estimated for dental caries, controlling for confounders. Results879 children had dental examinations at five years-of-age. Group-based trajectory modeling identified three trajectories of maternal SSB intake: ‘Stable low’ (40.8%), ‘Moderate but increasing’ (13.6%), and ‘High early’ trajectory (45.6%). Multivariable regression analysis found children of mothers in the ‘High early’ and ‘Moderate but increasing’ groups to have greater experience of dental caries (MR: 1.37 (95%CI 1.01–1.67), and 1.24 (95%CI 0.96–1.60) than those in the ‘Stable low’ trajectory, respectively. ConclusionMaternal consumption of SSB during pregnancy and in the early postnatal period influenced their offspring's oral health. It is important to create a low-sugar environment from early childhood. The results suggest that health promotion activities need to be delivered to expecting women or soon after childbirth.

The influence of early-life residential exposure to different vegetation types and paved surfaces on early childhood development: A population-based birth cohort study

BackgroundGrowing evidence suggests that exposure to green space is associated with improved childhood health and development, but the influence of different green space types remains relatively unexplored. In the present study, we investigated the association between early-life residential exposure to vegetation and early childhood development and evaluated whether associations differed according to land cover types, including paved land. MethodsEarly childhood development was assessed via kindergarten teacher-ratings on the Early Development Instrument (EDI) in a large population-based birth cohort (n = 27,539) in Metro Vancouver, Canada. The residential surrounding environment was characterized using a high spatial resolution land cover map that was linked to children by six-digit residential postal codes. Early-life residential exposure (from birth to time of EDI assessment, mean age = 5.6 years) was calculated as the mean of annual percentage values of different land cover classes (i.e., total vegetation, tree cover, grass cover, paved surfaces) within a 250 m buffer zone of postal code centroids. Multilevel models were used to analyze associations between respective land cover classes and early childhood development. ResultsIn adjusted models, one interquartile range increase in total vegetation percentage was associated with a 0.33 increase in total EDI score (95% CI: 0.21, 0.45). Similar positive associations were observed for tree cover (β-coefficient: 0.26, 95% CI: 0.15, 0.37) and grass cover (β-coefficient: 0.12, 95% CI: 0.02, 0.22), while negative associations were observed for paved surfaces (β-coefficient: −0.35, 95% CI: −0.47, −0.23). ConclusionsOur findings indicate that increased early-life residential exposure to vegetation is positively associated with early childhood developmental outcomes, and that associations may be stronger for residential exposure to tree cover relative to grass cover. Our results further indicate that childhood development may be negatively associated with residential exposure to paved surfaces. These findings can inform urban planning to support early childhood developmental health.

Living proximity to petrochemical industries and the risk of attention-deficit/hyperactivity disorder in children

Evidence regarding the negative neurodevelopmental effects of compound exposure to petrochemicals remains limited. We aimed to evaluate the association between exposure to petrochemical facilities and generated emissions during early life and the risk of attention-deficit/hyperactivity disorder (ADHD) development in children. We conducted a population-based birth cohort study using the 2004 to 2014 Taiwanese Birth Certificate Database and verified diagnoses of ADHD using the National Health Insurance Database. The level of petrochemical exposure in each participant's residential township was evaluated using the following 3 measurements: distance to the nearest petrochemical industrial plant (PIP), petrochemical exposure probability (accounting for monthly prevailing wind measurements), and monthly benzene concentrations estimated using kriging-based land-use regression models. We applied Cox proportional hazard models to evaluate the association. During the study period, 48,854 out of 1,863,963 children were diagnosed as having ADHD. The results revealed that residents of townships in close proximity to PIPs (hazard ratio [HR] = 1.20, 95% confidence interval [CI]: 1.16–1.23, <3 vs. ≥10 km), highly affected by petrochemical-containing prevailing winds (HR = 1.12, 95% CI: 1.08–1.16, ≥40% vs. <10%), and with high benzene concentrations (HR = 1.26, 95% CI: 1.23–1.29, ≥0.75 vs. <0.55 ppb) were consistently associated with the increased risk of ADHD development in children. The findings of the sensitivity analysis remained robust, particularly for the 2004 to 2009 birth cohort and for models accounting for a longer duration of postnatal exposure. This work provided clear evidence that living near petrochemical plants increases the risk of ADHD development in children. Further studies are warranted to confirm our findings.

Serum Testosterone Levels in 3-Month-Old Boys Predict Their Semen Quality as Young Adults.

ContextIt remains unknown how the postnatal activation of the hypothalamic-pituitary-gonadal axis in infancy, also known as “minipuberty”, relates to adult testis function.ObjectiveTo investigate how markers of reproductive function in 3-month-old boys correlate with adult reproductive health parameters.MethodsThis population-based birth cohort study (the Copenhagen Mother-Child cohort), conducted at Copenhagen University Hospital, Denmark, included 259 boys examined once around 3 months of age and again at 18 to 20 years. Reproductive hormones, penile length, testis volume, and semen quality were analyzed. Minipubertal markers of testis function (by tertiles, T1–T3) were explored as predictors of adult semen quality using linear regression models. Associations between reproductive outcomes in infancy and young adulthood were estimated by intraclass correlation coefficients (ICCs), describing how well measurements in infancy correlate with those in adulthood.ResultsSerum testosterone concentration in infancy was positively associated with adult total sperm count. Median (IQR) total sperm count was 84 (54-138) million spermatozoa for boys in T1, 141 (81-286) million spermatozoa in T2, and 193 (56-287) million spermatozoa in T3. We found the highest ICC for FSH (0.41; 95% CI, 0.26–0.57), while ICCs for inhibin B, SHBG, penile length, and testis volume ranged between 0.24 and 0.27. ICCs for LH and for total and free testosterone were lower and statistically nonsignificant.ConclusionSerum testosterone in infancy was a predictor of adult total sperm count. Other reproductive hormones and genital measures showed good correlation between infancy and adulthood, suggesting that an individual’s reproductive setpoint starts shortly after birth in boys and persists until adulthood.

Bacillus Calmette-Guerin vaccination and multiple sclerosis: A population-based birth cohort study in Quebec, Canada.

The bacillus Calmette-Guerin (BCG) vaccine could reduce the incidence of multiple sclerosis (MS) through immunomodulation. Previous studies, presenting some limitations, reported no association. We re-examined this association in a large cohort focusing on relapsing-remitting MS (RRMS). The cohort included 400,563 individuals, and was linked with the Quebec provincial BCG vaccination registry and administrative health data. Individuals were followed up from 1983 to 2014 and then within Period 1 (1983-1996) and Period 2 (1997-2014), for the occurrence of MS. Incident MS cases were defined as those with ≥3hospital or physician claims for MS. Subjects with ≥1 drug reimbursement for MS disease-modifying therapies were classified as RRMS. Cox proportional hazards regression was used to estimate hazard ratios (HRs) over the follow-ups, adjusting for potential confounders. Possible effect modification due to sex was assessed. A total of 178,335 (46%) individuals were BCG vaccinated. There were 274 (0.06%) incident MS cases identified in 1983-1996, and 1433 (0.4%) in 1997-2014. No association was found with RRMS, either in Period 1 (adjusted HR [HRadj ]=0.96, 95% confidence interval [CI] = 0.63-1.45; 96 cases) or in Period 2 (HRadj =1.02, 95% CI = 0.85-1.23; 480 cases). The remaining MS cases, for whom the phenotype was unknown, were positively associated with BCG over the entire follow-up (HRadj =1.25, 95% CI = 1.10-1.41; 1131 cases) and in Period 2 (HRadj =1.33, 95% CI = 1.17-1.52; 953 cases). No interaction with sex was found. Findings suggest that BCG vaccination does not decrease the risk of RRMS, and that future studies should consider phenotypes of MS.