External Publications Using GUI Data

Background
Globally, childhood obesity is a significant public health problem associated with adverse health and economic consequences. To tackle the problem, we need a comprehensive understanding on how the environment in which we live may influence obesity related behaviours and weight status. Thus, we explore if distance to and number of food outlets ([1] supermarkets and [2] convenience stores) in the local area impact on either dietary quality or body mass index (BMI) in 9-year-old children whilst controlling for socio-economic characteristics of the family.

Methods
Cross sectional analysis of the Growing Up in Ireland (GUI) Study, a two-stage clustered sample of 8568 nine year old children from the Republic of Ireland. Children were recruited from schools (response rate 82%) and age eligible children (response rate 57%) were invited to participate. Height and weight measurements were used to calculate BMI. Diet was assessed using a short food frequency questionnaire and a dietary quality score was generated based on Irish healthy eating guidelines. Socio-economic status was measured using parent reported household class, household net equivalised income and highest level of maternal education. Food access was measured as network distance to (in quintiles) and number of (within 1000km) convenience stores and supermarkets to each participant’s household within the local area. Separate fixed effects regression models were used to assess the impact of local area food access on (1) dietary quality and (2) BMI, stratified by gender.

Results
After controlling for socio-economic characteristics of the household, distance to the nearest supermarket was not associated with dietary quality in boys (Q5 v Q1; B = 0.84, 95% CI, –0.49 to 2.18) or girls (Q5 v Q1; B = –0.41, 95% CI, –1.60 to 0.77). Distance to the nearest convenience store was associated with dietary quality in boys (Q5 v Q1; B = 1.01, 95% CI, 0.13 to 1.89) but not in girls (Q5 v Q1; B = 0.04, 95% CI, –0.71 to 0.80). The number of convenience stores or supermarkets within 1000m of the household did not impact on dietary quality. Access to food outlets was not associated with BMI in girls or boys.

Conclusion
There was little evidence to suggest that access to food stores impact dietary quality or BMI in children. From a population health perspective, strategies tackling environmental factors associated with making poor lifestyle choices are needed. Thus, further research on the association between food access and obesity risk is needed.

Importance As young people’s mental health difficulties increase, understanding risk and resilience factors under challenging circumstances becomes critical.

Objective To explore the outcomes of the COVID-19 pandemic on secondary school students’ mental health difficulties, as well as the associations with individual, family, friendship, and school characteristics.

Design, Setting, and Participants For this cohort study, follow-up data from the My Resilience in Adolescence (MYRIAD) cluster randomized clinical trial were collected across 2 representative UK cohorts. Mainstream UK secondary schools with a strategy and structure to deliver social-emotional learning, with an appointed head teacher, and that were not rated “inadequate” in their latest official inspection were recruited. A total of 5663 schools were approached, 532 showed interest, and 84 consented. Cohort 1 included 12 schools and 864 students, and cohort 2 included 72 schools and 6386 students. COVID-19 was declared a pandemic after cohort 1 had completed all assessments (September 2018 to January 2020), but cohort 2 had not (September 2019 to June 2021).

Exposures Cohort 2 was exposed to the COVID-19 pandemic, including 3 national lockdowns. Associations of individual, family, friendship, and school characteristics with students’ mental health were explored.

Main Outcomes and Measures Changes in students’ risk for depression (Center for Epidemiological Studies-Depression scale); social, emotional, and behavioral difficulties (Strengths and Difficulties Questionnaire); and mental well-being (Warwick-Edinburgh Mental Well-Being Scale).

Results Of the 7250 participants included, the mean (SD) age was 13.7 (0.6) years, 3947 (55.4%) identified as female, and 5378 (73.1%) self-reported their race as White. Twelve schools and 769 of the 864 students (89.0%) in cohort 1 and 54 schools and 2958 of the 6386 students (46.3%) in cohort 2 provided data and were analyzed. Mental health difficulties increased in both cohorts but to a greater extent among students exposed to the pandemic, including for risk of depression (adjusted mean difference [AMD], 1.91; 95% CI, 1.07-2.76); social, emotional, and behavioral difficulties (AMD, 0.76; 95% CI, 0.33-1.18); and mental well-being (AMD, −2.08; 95% CI, −2.80 to −1.36). Positive school climate, high home connectedness, and having a friend during lockdown were protective factors during the pandemic. Female gender and initial low risk for mental health difficulties were associated with greater mental health deteriorations. Partial school attendance during lockdown was associated with better adjustment than no attendance when returning to school.

Conclusions and Relevance This cohort study of secondary school students demonstrated that to promote mental health and adjustment, policy interventions should foster home connectedness, peer friendship, and school climate; avoid full school closures; and consider individual differences.

Importance Birth weight percentiles (BWPs) are often dichotomized at the 10th percentile and show statistically significant association with later cognitive performance, for both preterm and term-born children. However, research testing nonlinear associations between BWPs and cognitive performance is scarce.

Objective To investigate culturally invariant, nonlinear associations of BWPs and gestational age with later cognitive performance.

Design, Setting, and Participants In this cohort study, participants with valid neonatal and cognitive data were combined from 4 observational cohorts, including the Millennium Cohort Study, the National Longitudinal Survey of Youth 1979 Child and Young Adult cohort, Growing Up in Ireland, and the Longitudinal Study of Australian Children, with children born between 2000 and 2002, 1980 and 2010, 2007 and 2008, and 2003 and 2004, respectively. Neonatal data were parent reported before age 1 year. At approximately 5 years of age, multiple cognitive tests were performed. Follow-up at 5 years of age was the predominant focus. Data were analyzed July 17, 2023.

Exposure The parent-reported neonatal data were used to calculate BWPs according to the Fenton growth chart.

Main Outcome and Measure Scores for IQ were created from multiple measures of cognition, which were z standardized separately within each cohort.

Results Of 30 643 participants (50.8% male), 7.5% were born preterm (before 37 weeks gestation) and 92.5% were term born (between 37 and 42 weeks gestation). In the pooled data using multivariate adaptive regression splines, IQ linearly increased by 4.2 points as BWPs increased from the first to the 69th percentile before completely plateauing. For gestational age, IQ linearly increased by 1.3 points per week up until 32 weeks, with the association reducing to 0.3 points per week after 32 weeks. The association of BWP with IQ was not moderated by gestational age. For term-born infants, the estimated IQ score was only clinically meaningfully lower than average when birth weight was below the third percentile. Consistent results were found when instead using multivariable regression where gestational age and BWPs were categorized into groups.

Conclusions and Relevance In this cohort study, lower BWPs and gestational age were independently associated with lower IQ. For term-born infants, a cutoff of the third percentile would be more appropriate than the traditionally used 10th percentile when the aim is estimating meaningful cognitive differences.

Importance Understanding which children in the general population are at greatest risk of poor functional outcomes could improve early screening and intervention strategies.

Objective To investigate the odds of poor outcomes in emerging adulthood (ages 17 to 20 years) for children with different mental health trajectories at ages 9 to 13 years.

Design, Setting, and Participants Growing Up in Ireland is a longitudinal, nationally representative population-based cohort study. Data collection began in August 2007 and was repeated most recently in September 2018. All results were weighted to account for sampling bias and attrition and were adjusted for socioeconomic factors. Data analysis took place from October 2022 to April 2023.

Exposure Four latent classes captured variation in mental health in children aged 9 and 13 years, based on the parent-completed Strengths and Difficulties Questionnaire. Classes included no psychopathology, internalizing, externalizing, and high (comorbid) psychopathology. Those who remained in the same class from ages 9 to 13 years were included.

Main Outcomes and Measures Poor functional outcomes in emerging adulthood were measured at approximate ages 17 years (range, 16 to 18 years) and 20 years (range, 19 to 21 years). Outcomes included poor mental health, poor physical health, social isolation, heavy substance use, frequent health service use, poor subjective well-being, and adverse educational/economic outcomes.

Results Of 5141 included participants, 2618 (50.9%) were male. A total of 3726 (72.5%) were classed as having no childhood psychopathology, 1025 (19.9%) as having persistent externalizing psychopathology, 243 (4.7%) as having persistent internalizing psychopathology, and 147 (2.9%) as having persistent high psychopathology. Having any childhood psychopathology was associated with poorer functional outcomes in emerging adulthood. The internalizing group had elevated odds of most outcomes except for heavy substance use (range of odds ratios [ORs]: 1.38 [95% CI, 1.05-1.81] for frequent health service use to 3.08 [95% CI, 2.33-4.08] for poor mental health). The externalizing group had significantly elevated odds of all outcomes, albeit with relatively small effect sizes (range of ORs: 1.38 [95% CI, 1.19-1.60] for frequent health service use to 1.98 [95% CI, 1.67-2.35] for adverse educational/economic outcomes). The high psychopathology group had elevated odds of all outcomes (nonsignificantly for frequent health service use), though with wide confidence intervals (range of ORs: 1.53 [95% CI, 1.06-2.21] for poor physical health to 2.91 [95% CI, 2.05-4.12] for poor mental health). Female participants with any psychopathology had significantly higher odds of poor physical health and frequent health service use compared with male participants with any psychopathology.

Conclusions and Relevance In this longitudinal cohort study, childhood psychopathology was associated with a widespread pattern of functional impairment in emerging adulthood. Findings point to the need for a wider range of preventive interventions in child and adolescent mental health services.

Introduction
Despite a growing body of research on associations between adolescent digital use and well-being, few studies have investigated these associations a) longitudinally and b) across socioeconomic status. The present study uses high-quality longitudinal data to examine how digital engagement shapes socioemotional and educational outcomes from early to late adolescence across socioeconomic status (SES).

Methods
Participants are 7685 individuals (49.0% female) from the 1998 birth cohort of the longitudinal Growing Up In Ireland (GUI) survey. The survey was administered to Irish parents and children between 2007 and 2016 (at ages 9, 13, and 17/18). Fixed-effects regression modeling was used to establish associations between digital engagement and socioemotional and educational outcomes. Further Fixed-Effects models were analyzed separately by SES, to assess how associations between digital use and adolescent outcomes differ by socioeconomic groups.

Results
Results show that digital screen time increases markedly from early to late adolescence, but to a higher extent among low-SES versus high-SES groups. Heavy levels of digital screen time (i.e., 3+ hours daily) are associated with declines in well-being, particularly for external and prosocial functioning, while engagement in learning-oriented digital activities and gaming is associated with better adolescent outcomes. Yet, low-SES adolescents are globally more harmed than high-SES adolescents by their digital engagement, and high-SES adolescents benefit more from moderate levels of digital use and from engaging in learning-oriented digital activities.

Conclusions
This study suggests that digital engagement is associated with socioeconomic inequalities in adolescents’ socioemotional well-being and, to a lesser extent, educational outcomes.

Introduction
The aim of this paper was to examine the role of perinatal, obstetric and post partum factors on maternal and paternal stress. It will present the first examination of the role of prenatal, obstetric, post-partum, and demographic variables in parenting stress for mothers and fathers at 9 months.

Methods
Data from 6821 parental dyads of 9-month-old infants were extracted from the Growing Up in Ireland National Longitudinal Study of Children. Participants completed the Parental Stress Scale, the Dyadic Adjustment Scale, the Quality of Attachment Sub-scale from the Maternal and Paternal Postnatal Attachment Scales, and a single item health status question from the Short Form 12 Health Survey. Information on prenatal care, pregnancy complications, obstetric outcomes, infant health, and participant demographics were also collected. Separate hierarchical linear regressions were conducted for mothers and fathers

Results
Mothers reported higher levels of parenting stress than fathers (p < 0.001). Maternal parenting stress was predicted by attachment, own health status, average sleep, occupation, household income, and having a very rapid labor. Paternal parenting stress was predicted by attachment and own health status.

Discussion
A range of perinatal factors was associated with an increased risk of higher parenting stress at 9 months post-partum and the roles of these factors differ between mothers and fathers. These findings are important for predicting and reducing risk of parenting stress in both genders.

Keywords
Attachment, obstetric outcomes, parenting stress, prenatal, well-being

Introduction
The COVID-19 pandemic wrought acute harm to mental wellbeing across the globe; not least through its impact on morbidity and mortality, but also from health anxieties, lockdowns and their economic fallout, the closure of key services, as well as the disruption of social networks. However, while the pandemic’s onset was global, not everyone experienced the same harm to their mental health. This study draws on information on the mothers of 12-year-olds from the Growing Up in Ireland (GUI) study to look at what helped cushion the negative impact of the pandemic on their mental health.

Data and Methods
The study draws on GUI data on Cohort ’08, a nationally representative sample of children born 2007-2008 along with their caregivers. In December 2020, the GUI team conducted a survey of primary caregivers (98 per cent of whom are mothers) during the COVID-19 pandemic. Mothers’ mental health is captured using the Short-form Center for Epidemiological Studies Depression Scale (CES-D), with higher scores indicating a greater risk of depression. The longitudinal nature of GUI means we can compare measures of mothers’ mental health during the COVID-19 pandemic (December 2020) with two previous timepoints before the pandemic – wave 3 (2013/2014) and wave 5 (2017/2018) – to see whether trends in depression changed significantly over the pandemic.

The study looks at four sets of factors: (1) mothers’ social resources, such as the level of social cohesion in their neighbourhood (e.g., trust and reciprocity among neighbours) or the support they receive from friends/family; (2) their economic resources, such as the share of income received from welfare, or how difficult they feel it is to ‘make ends meet’; (3) the quality of mothers’ local environment, such as the degree of traffic problems; and (4) their religiosity, such as how often they attend church. All of these factors are measured prior to the onset of the pandemic to reflect the resources mothers had at their disposal going into the crisis.

To understand how these buffering factors may have cushioned mothers’ mental health, the study uses a set of measures on what experiences mothers had during the pandemic. These include whether they found supervising their child’s schoolwork stressful, whether they experienced a loss of income/employment, or whether they had COVID or were anxious about friends/family contracting it.

Results

What factors cushioned the impact of the pandemic on mothers’ mental health?

In the years prior to the pandemic (2013/2014 to 2017/2018), levels of depression among mothers remained relatively low and stable. However, depression scores among mothers rose steeply with the onset of the pandemic (compared to 2017/18), nearly doubling. Yet, not all mothers experienced an equal increase in depression scores.

Stronger economic resources, and better household conditions, played a protective role: depression scores rose less among mothers who reported being able to ‘financially make ends meet’ easily (compared to those who found it difficult) and among mothers who lived in less overcrowded housing. The local environments in which mothers were living also helped cushion their mental health. Mothers who lived in neighbourhoods where heavy traffic was not a problem, and those who lived in rural areas, saw their depression scores increase less over the pandemic, compared to mothers in more urban areas or where traffic was a major problem.

The strongest protective factors were mothers’ social resources and their religiosity. Mothers who, just before the pandemic, had a partner in the household and who felt they got the help they needed from friends and family saw their depression scores increase less over the pandemic. Those who reported living in more socially cohesive neighbourhoods (where neighbours trust each other, exchange favours, or feel more attached) – what are termed in the research literature as high social capital areas – were more strongly protected against depression during the pandemic. Symptoms of depression also increased much more steeply among mothers who never attended church before the pandemic compared to mothers who used to attend daily or weekly (even though in-person services had not resumed at the time of the survey).

How did these buffering factors protect mothers’ mental health?

Social resources cushioned mothers’ mental health because, during the pandemic, these mothers experienced better family relations and struggled less with care work, home schooling, and their children’s return to school. Economic resources supported mental wellbeing by reducing financial stresses, enabling better home/outdoor environments, and likely allowing families to purchase the tablets, laptops, and high-speed internet needed to engage in home schooling and working more easily. A better-quality local environment allowed mothers to spend more time outside and improved family relations. It was harder to explain the protective role of religiosity, but it may relate to greater optimism or a stronger sense of meaning in life that help protect people from the stress of adversity.

Conclusion and policy implications
This study finds strong evidence that the social, economic, religious, and environmental characteristics in people’s lives protect their mental health when experiencing adverse life events. While some of these characteristics are personal, others can be influenced by policy. Investment in local infrastructure to enhance access to green spaces and reduce neighbourhood disorder will pay dividends in supporting the mental wellbeing of women and their families. Furthermore, community development initiatives to foster a sense of local belonging and trust will enhance families’ capacity to weather crises. Integrating such perspectives into crisis management could help protect societies, particularly more vulnerable groups, and potentially weaken the well-documented long-term scarring effects that adverse life events have on people’s lives.

Objective
Childhood chronic illness can have a high impact on the child’s quality of life. The foundations of health are established in early life, and are shaped by biological, psychosocial, spiritual and environmental processes and influences. The objectives of this presentation are twofold: firstly to describe the prevalence of chronic illness in 9-year-olds in Ireland, secondly to illustrate how chronic illness influences the psychological and social development of the children.

Methods
Analysis was based on data of 8570 9-year old children, and their families who participated in Growing Up in Ireland—the National Longitudinal Study of Children. The sample was generated through the primary school system. A representative sample of 910 schools participated; the sample of children and their families was randomly selected from within the schools. Questionnaires were administered in schools; and after completion of this phase, the project interviewers visited the families of the 9-year olds in their homes and administered core questionnaires to the Study Child and his/her carers who provided either home-based or centre-based care on a regular basis.

Results
The overall prevalence of chronic illness reported by mothers among the 9-year old cohort was 11% (gender-specific prevalence for boys: 13%, and significantly lower for girls: 10%). Respiratory illnesses accounted for almost half (46%) of all chronic illnesses, followed by mental and behavioural conditions with 19% (high gender dysbalance: reported for boys in 24%, for girls in 12%). Children with a reported chronic illness had significantly more emotional, conduct, hyperactivity, peer-based and prosocial difficulties when compared with children without a reported chronic illness. Abnormal scores, based on the Strengths and Difficulties Questionnaire were found in 20% in children with a chronic disease, and in 5.5% in children without a chronic disease. Socio-economic Status was associated with poorer health outcomes. Furthermore, primary care givers’ views and perceptions regarding the chronic illness of the child were found to be a significant factor on child strengths and difficulties in a multivariate model.

Conclusions
The majority of 9-year old children can be assessed as healthy. The most common chronic illness in this large cohort was respiratory disease and overall, chronic conditions were found to have a negative impact on the child’s emotional and social state.

Objective
Early complementary feeding has been shown to increase the risk of overweight, obesity and chronic diseases later in life. Poor compliance with current guidelines on complementary feeding has been reported by Irish studies. The aim of the present paper is to identify predictors of early complementary feeding in order to help health professionals target population groups in greater need of dietary intervention as well as to provide effective advice.

Design
Cross-sectional analysis of the national, longitudinal Growing Up in Ireland study.

Setting
Data were derived from the first wave (2007–2008) of the Growing Up in Ireland infant cohort.

Subjects
A cohort of mothers (n 11 134) from the Republic of Ireland, interviewed when their infants were 9 months of age.

Results
Of the infants, 1469 (13·5 %) had been regularly taking solids in the period between 12 and 16 weeks; this percentage increased to 47·0 % of the sample in the period between 16 and 20 weeks. Timing of formula feeding commencement, high maternal BMI and choosing a relative as the infant’s minder were strongly associated with early introduction of solids both in bivariate and multivariate analysis. Those infants who started formula feeding at >4 months were 88·4% less likely to be introduced to solids early compared with those who started at <2 months (OR = 0·116; 95% CI 0·072, 0·186; P < 0·001).

Conclusions
The results demonstrate that biological, social and behavioural aspects exert an important role in infant feeding practices. These findings are relevant to the design of policies and intervention programmes aimed at educating parents.

Keywords
Complementary feeding, Infant’s diet, Early weaning

Objective
The purpose of this study was to examine the relationship between maternal obesity that is calculated 9 months after delivery and sociodemographic variables.

Study Design
A national cohort of mothers was sampled 9 months after delivery as part of the Growing Up in Ireland Study Infant Cohort. Sociodemographic and clinical details were recorded at the interview by trained fieldworkers who used validated questionnaires. Body mass index was calculated based on weight and height measurements at the postpartum interview. The unadjusted and adjusted odds of obesity were calculated for predictor variables with the use of logistic regression analysis.

Results
Of the 10,524 mothers whose cases were studied, the mean age was 31.6 ± 5.5 years, and the mean parity was 1.0 ± 1.1. The mean body mass index after delivery was 25.7 ± 5.4 kg/m2; 16.8% of the women (n = 1768) were obese. Postpartum maternal obesity levels were associated positively on univariable analyses with smoking, lower household income, African nationality, earlier completion of full-time education, gestational weight gain, lower breast-feeding duration, and increasing parity. On multivariable analysis, maternal obesity was associated with increasing parity in lower income households, but not in higher income households.

Conclusion
Public health interventions that are aimed at decreasing obesity levels after childbirth should prioritize women who are disadvantaged socioeconomically.

Keywords
maternal obesity, parity, postpartum weight

Objective
This paper examines the joint impact of maternal employment and childcare during infancy on childhood weight at ages three and five in the context of weak social support for early childhood care and education.

Method
Using three waves of longitudinal data from the Growing-Up in Ireland survey (n = 8,393 age three, n = 8,039 age five), propensity score matching is used to address the endogeneity of employment and childcare decisions. Selection on observables is used to assess potential bias arising from selection on unobservables whereby unobserved characteristics of the mother or child may jointly influence child weight and maternal employment and childcare.

Results
Full-time maternal employment at nine months combined with either formal or informal childcare increases the likelihood of being overweight at three years by 8.1% and 5.9% respectively, but only for children of highly educated mothers. Similar results are observed for part-time employment coupled with informal (7.5%) or parental (8.0%) care. The results for mothers with lower levels of education are either not significant or favourable. While the majority of the effects dissipate by age five, there is some evidence that full-time maternal employment coupled with informal care increases the risk of being overweight at both ages three and five for children of higher-educated mothers. An assessment of selection bias finds that the estimates of full-time employment combined with formal childcare by well-educated mothers are a lower bound, such that the true effect on child weight may be understated.

Conclusions
The findings for Ireland are consistent with studies from the United States and the United Kingdom, and are in contrast to findings from the rest of Europe, suggesting the role of institutional factors, such as the lack of subsidised, universal, high-quality childcare.

Objective
This study aims to examine the associations between prenatal exposure to maternal smoking, birth weight and persistent offspring psychiatric symptoms. Additionally, we aim to examine whether the relationship between prenatal maternal smoking and persistent offspring psychiatric symptoms is mediated by offspring birth weight.

Methods
This study used the Growing Up in Ireland (GUI) longitudinal cohort. The GUI is a nationally representative longitudinal study of children which consisted of three data collection waves, at ages 9, 13, and 17 years. Logistic regression analysis was used to examine associations between prenatal tobacco exposure, and offspring psychiatric symptoms. Linear regression was used to examine associations between prenatal tobacco exposure and offspring birth weight. We conducted a mediation analysis examining potential etiological pathways linking maternal smoking during pregnancy, offspring birth weight, and later offspring psychiatric symptoms. All analyses were adjusted for confounders including household income, maternal level of education, and family psychiatric history. Additionally, examination of birth weight and subsequent psychiatric symptoms also was controlled for prematurity.

Results
We found that the association between prenatal tobacco exposure and later psychiatric symptoms is mediated by birth weight.

Conclusions
This work provides further evidence that maternal smoking during pregnancy is an important modifiable lifestyle factor that has an impact not just on the physical health of offspring but also their mental wellbeing. Supporting women with structured smoking cessation programs at the earliest stages of pregnancy should be a public health priority.

Objective
This study examines the association between attention-deficit/hyperactivity disorder (ADHD) and overweight/obesity in a large-scale longitudinal study of children, while controlling for a range of psychosocial factors.

Method
Data were obtained from Growing Up in Ireland, a nationally representative and longitudinal study of approximately 6500 children who were assessed at 9 and 13 years of age. Body mass index (BMI) was determined using measured height and weight, ADHD status was determined by parent reports of professional diagnoses and ADHD symptoms were measured using the Strengths and Difficulties Questionnaire (SDQ).

Results
The associations between ADHD status, ADHD symptoms (SDQ) and BMI category at age 9 and 13 years were evaluated using logistic regression. Adjustments were made for child factors (sex, developmental coordination disorder, emotional symptoms, conduct problems, birth weight and exercise) and parental factors (socio-economic status, parental BMI, parental depression, and maternal smoking and alcohol use during pregnancy). Logistic regression indicated that ADHD status was not associated with BMI category at 9 or at 13 years of age, but children with ADHD at 9 years were significantly more likely to be overweight/obese at 13 years than those without ADHD. However, when other child and parental factors were adjusted for, ADHD status was no longer significantly associated with weight status. Female sex, low levels of exercise, overweight/obese parents and prenatal smoking during pregnancy consistently increased the odds of childhood overweight/obesity.

Conclusions
While ADHD and overweight/obesity co-occur in general populations, this relationship is largely explained by a variety of psychosocial factors.

Keywords
ADHD, longitudinal, obesity, overweight, psychosocial

Objective
To examine the extent to which early child nutrition, maternal antenatal lifestyle behaviours and child diet and lifestyle explain social class inequalities in the risk of rapid weight gain between birth and 3 years and obesity at age 3 years.

Design
A longitudinal and prospective birth cohort study.

Subjects
Nationally representative sample of 11 134 children and their parents followed from 9 months of age until 3 years. Child weight and maternal height and weight were measured at 9 months and 3 years and child birth weight was extracted from hospital records. Other predictors of child growth and obesity were collected by maternal report at 9 months and 3 years.

Results
Although born lighter on average, children of unskilled manual parents were 274 g heavier than children of professional parents by 3 years of age. The fully adjusted model of rapid growth from birth to 3 years of age and obesity at 3 years of age accounted for all social class differentials. Breastfeeding and age at the introduction of solids were associated with the largest average reduction (41%) in the odds ratio (OR) of rapid growth in the first 9 months of life for each class relative to the professional class. In the period from 9 months to 3 years of age, the class differential in rapid growth was reduced most by measures of the child’s diet and lifestyle. However, the impact of the groups of predictors varied by social class. For early life growth, among the non-manual classes the proportionate reductions are largest when adjusted for early infant nutrition, whereas maternal prenatal smoking is more important for the manual social classes.

Conclusion
Preventative interventions to reduce levels of childhood obesity should be multi-dimensional but different dimensions should be given more or less significance depending on socio-economic group.

Objective
To explore whether the associations between developmental delays in the first year of life and psychosocial outcomes in preschool children are affected by participation in organized sport.

Study design
Data were obtained from the infant cohort of the Growing Up in Ireland project. Parents reported on child development (Ages and Stages Questionnaire) at age 1 year, psychosocial characteristics (Strengths and Difficulties Questionnaire) at ages 3 and 5 years, and engagement in organized sport at age 5 years. Data were analyzed using mixed models.

Results
At age 1 year, 15% of the cohort was classified as having developmental delays. These children exhibited more behavioral difficulties (0.55, ±0.27; mean difference, ±95% confidence limits [CL]) (P < .0001) and fewer prosocial behaviors (−0.54, ±0.11) (P < .0001) at age 3 years. For boys in this group, engagement in sport was associated with a significant decrease in behavioral difficulties between ages 3 and 5 years (−0.44, ±0.39) (P = .03). Compared with those classified as lacking regular engagement (ie, never engaging, or engaging <1 hour/week), the relative effect of sport on changes in behavioral difficulties for boys with developmental delays was statistically significant (0.70, ±0.59) (P = .02). Participation in sport was not associated with significant changes in behavioral difficulties for girls, or a significant change in prosocial behaviors for boys or girls.

Conclusions
Regular participation in sport by boys could attenuate some of the behavioral difficulties associated with early development. Lack of opportunities for engaging in sport could negatively affect boys’ behavioral regulation in the preschool period.

Objective
To longitudinally investigate body mass index (BMI) in young children in Ireland and identify factors and critical time points associated with changes in BMI.

Study design
Data on 11 134 children were collected in the nationally representative Growing Up in Ireland infant cohort study. Height and weight were measured at 9 months, 3 years, and 5 years of age. Multilevel regression was used to identify risk factors associated with changes in BMI over time (n = 10 377), combining a unique set of covariates collected from the child and the 2 main caregivers (usually the mother and father).

Results
The proportion of children ≥85th percentile of World Health Organization growth criteria was 39% at 9 months, 44% at 3 years, and 30% at 5 years. Children born large for gestational age (13%) and those with rapid infant weight gain (25%) consistently had higher BMI. Low average BMIs were consistently seen in children born small for gestational age (10%) or before 37 weeks (7%). Smaller variations in BMI existed for other factors including ethnicity, household structure, caregiver weight status, breastfeeding, sex, socioeconomic status, sleeping hours, childcare, and region.

Conclusions
In this study, differences at birth and in infancy appear to be most strongly associated with variation in BMI at all ages. Nevertheless, belonging to a number of other high-risk groups cumulatively could lead children to develop critical weight states. Policy-makers should target families with interventions before and during pregnancy when dominant risk factors are still modifiable. Longer-term follow-up of children may be needed to study associations later in childhood.

Keywords
Growing Up in Ireland, body mass index, childhood obesity, growth trajectories, multilevel modelling

Objectives
Maternal health behaviours (MHBs) can influence pregnancy outcomes. Despite efforts internationally to encourage positive MHBs, women often fail to comply with pregnancy guidelines. International studies show differences in MHBs between nationalities and an effect of time spent in the host country. There is limited Irish data in this area, with no previous research relating to the effect of time in Ireland.

Study design
This study is a cross-sectional analysis of the Growing Up in Ireland infant cohort, a nationally representative longitudinal study.

Methods
Examination of the MHBs of non-Irish nationals during pregnancy and the effect of time in Ireland on the said behaviours.

Results
An association was found between time spent in Ireland and increased alcohol consumption prevalence. Those living in Ireland for ≤5 years were 60.8% less likely to consume alcohol during pregnancy (0.000) and 29.3% less likely to take folic acid before conception (0.021). Those who smoked during pregnancy were 98.6% more likely to consume alcohol (0.000) and those who consumed alcohol were 95.2% more likely to smoke during pregnancy (0.000).

Conclusions
The results demonstrate differences in MHBs and the influence of time living in Ireland. These findings are of relevance for policy and intervention planning to optimise pregnancy outcomes among non-nationals.

Objectives
Migrant youths endure many challenges. Such challenges can be stressful and lead to psychological difficulties. We investigated the relationship between migration, psychopathology and stressful events in children and adolescents. We hypothesised that migrant youths would show higher levels of psychopathology and more stressful life events than non-migrant youths.

Method
Using the Child cohort (Cohort ‘98) of the ‘Growing up in Ireland’ study we investigated psychopathology, as measured by the Strengths and Difficulties questionnaire (SDQ) at age 9 and 13 and stressful life events in migrant and non-migrant youths.

Results
There was no significant difference between the proportion of migrant and non-migrant youths reporting psychopathology in childhood (p>0.05) or adolescence (p>0.05). Analysis of the SDQ subscales revealed that a significantly greater proportion of migrant youths had hyperactivity problems in childhood (p = 0.04) but a greater proportion of non-migrant youths had emotional problems in early adolescence (p = 0.04). We found that migrant youths experienced significantly more stressful life events than their non-migrant counterparts (p<0.01), however, once ‘Moving house/country‘ was removed as a stressor, there was no difference between the groups (p>0.27).

Conclusions
Contrary to our hypothesis, we observed that there were few differences between migrant and non-migrant youths in the levels of psychopathology. Migrant youths experienced a greater number of stressful life events, however, this was attributable to stressors relating to moving. An increased understanding of the factors promoting resilience, as demonstrated by the migrant youths, could aid health professionals and policy makers to effectively tailor interventions for mental health promotion.

Keywords
Early life stress, immigration, migrants, psychopathology

Objectives
To assess the impact of digital media usage on psychiatric symptoms in an adolescent population utilizing a longitudinal cohort design.

Methods
Using two waves of the GUI child cohort, age 13 (N = 7527) and age 17/18 (N = 6126), we used latent class analysis (LCA) to create latent groups centred around self-reported time spent online, and the self-reported behaviours children engaged with online. At both waves, the 4 class latent model suited best. We used the different symptoms scales of the Strengths and Difficulties Questionnaires (SDQ), self-reported, at age 17 as our outcome variable. Using linear regression analysis, we then examined the associations between our latent class model and psychiatric symptoms, using moderate usage as our reference group, with adjustments being made for baseline psychiatric symptoms, maternal education and pre-diagnosed mental disorder.

Results
For females, placement in the high usage group at 13 was associated with increased internalizing symptoms, whereas placement in the high usage group at 17 was associated with an increase in all symptoms. For males, placement in the high usage group at 17 was associated with increased emotional symptoms, and placement in the “low usage & behaviour engagement”group, a group showing low reported time online and low engagement in our measured online behaviours at 17, was associated with an increase in all symptoms. Finally for both sexes, placement in the “moderate usage, entertainment only” group at age 13, (a group reporting no school-based online engagement), was associated with increases in all symptoms except emotional symptoms.

Conclusion
High digital media usage is associated with increased psychiatric symptoms in both males and females, with moderate usage associated with positive effects on symptoms compared to both our high usage, and low usage groups.

Keywords
Digital engagement, Psychiatric symptoms, Internet usage, Latent class analysis

Objectives
To examine the associations between preeclampsia and longitudinal child developmental and behavioural outcomes using data from a nationally representative study of children living in Ireland.

Methods
We used maternal-reported data from the Growing Up in Ireland longitudinal study of children. Data on preeclampsia and preeclampsia + small for gestational age (SGA) were collected when children were 9-months old. Data on child development and behavioural outcomes were collected at 9-months using the Ages and Stages Questionnaire (ASQ), and at 3 years, 5 years and 7–8 years using the Strengths and Difficulties Questionnaire (SDQ). Multivariate logistic regression analysis was used to examine the association between preeclampsia exposure and failure of ASQ domains, and abnormal SDQ domains. Linear spline multilevel models were used to examine the association between preeclampsia and preeclampsia + SGA and repeated measures of SDQ. All models controlled for several perinatal and sociodemographic factors.

Results
A total of 10,692 children were included in the study at baseline, representing a weighted total of 70,791. Multivariate logistic regression suggested that preeclampsia was not associated with failing any ASQ domain. Preeclampsia was associated with abnormal SDQ cut-off of emotional (≥ 5) and hyperactivity (≥ 7) domains at age 5 years only. In the linear spline model, mean SDQ score was higher at each time point in exposed groups.

Conclusions for Practice
While we did not find strong evidence of associations between preeclampsia and child developmental and behavioural outcomes overall, some associations between preeclampsia-exposure and subtle behavioural issues did persist. Further research is needed to replicate these findings, and determine the clinical significance of changes in SDQ scores.