External Publications Using GUI Data

Background
Childhood adversity (CA) is commonly associated with an increased risk of subsequent psychopathology. It is important to identify potential mediators of this relationship which can allow for the development of interventions. In a large population-based cohort study we investigated the relationship between CA and late adolescent psychopathology and early adolescent candidate mediators of this relationship.

Methods
We used data from three waves (n = 6039) of Cohort 98′ of the Growing up in Ireland Study (age 9, 13 and 17). We used doubly robust counterfactual analyses to investigate the relationship between CA (reported at age-9) with psychopathology (internalizing and externalizing problems), measured using the Strengths and Difficulties Questionnaire at age-17. Counterfactual and traditional mediation was used to investigate the mediating effects of the parent-child relationship, peer relations, self-concept, computer usage and physical activity.

Results
CA was associated with an increased risk of internalizing and externalizing problems at age-17. Parent-child conflict mediated 35 and 42% of the relationship between CA and late adolescent externalizing problems and internalizing problems, respectively. Self-concept and physical activity mediated an additional proportion of the relationship between CA and internalizing problems. These results were robust to unmeasured confounding.

Conclusions
Parent-child conflict explains more than a third of the relationship between CA and later psychopathology. Self-concept and physical activity explain the additional proportion of the relationship between CA and internalizing problems. This suggests that these factors may be good targets for intervention in young people who have experienced CA to prevent subsequent psychopathology.

Keywords
Childhood adversity, parent-child conflict, psychopathology, self-concept and physical activity

Background
Childhood adversity is a well-established risk factor for psychopathology; however, many who experience adversity do not go on to develop psychopathology. Poor self-concept and poor parental support are known risk factors for adolescent psychopathology, which may account for some of this mechanism.

Aims
To investigate candidate mediators in the relationship between childhood adversity and psychopathology.

Method
We used data from the age 9 and 13 waves of the child-cohort of the Growing Up in Ireland study. We undertook mediation analysis by path decomposition of the relationship between childhood adversity and psychopathology (internalising and externalising problems) at age 13 and persistent psychopathology. Candidate mediators were self-concept, parent–child relationship and hobby participation at age 9.

Results
Childhood adversity was reported by 28.2% of participants, and was significantly associated with internalising and externalising problems. Parent–child conflict mediated the relationship between childhood adversity and both age 13 and persistent psychopathology, accounting for 52.4% of the relationship between childhood adversity and persistent externalising problems (indirect odds ratio, 1.30; 95% CI 1.19–1.43) and 19.2% for persistent internalising problems (indirect odds ratio, 1.24; 95% CI 1.15–1.34). There was a small mediating effect of self-concept. Hobby participation and positive parent–child relationship did not mediate these relationships.

Conclusions
Parent–child conflict explains almost half the relationship between childhood adversity and persisting externalising problems in adolescence, and a fifth of the relationship with persisting internalising problems. This suggests parent–child conflict is a good target for interventions in childhood to prevent adolescent psychopathology.

Background
Children with a parent who smokes are more likely to become substance users than those who do not have a parent who smokes. In this study, we examined whether childhood or early adolescent exposure to primary parent smoking increased the risk of subsequent teenage alcohol and drug use at ages 17–18 years.

Methods
For this longitudinal observational study, we analysed data from 6039 teenagers and their parents from the waves 1–3 of the Growing up in Ireland Cohort 98’ Study. Parental smoking was assessed at baseline (9 years) and wave 2 (13 years) with responses coded as yes or no. The primary parent was defined as the person who provided most care and who knew most about the Study Child, usually the mother or mother figure for 98% of study participants. Teenage alcohol and drug use assessed at ages 17–18 years (wave 3) was determined by responses to the question “Have you ever consumed alcohol?” (answers yes or no), drug use was assessed by questions on ever trying aerosols/gas, cannabis, and non-prescribed drugs, with those answering yes being classified as other-drug ever users. We did a logistic regression analysis to examine the associations between parents’ smoking on teenage alcohol and drug use, controlling for covariates: gender, education, income, education, region, and household type. Ethics approval for the GUI project was obtained from the Health Research Board.

Findings
Of the 6039 teenagers included in our study, 2968 (49%) were female, 3070 (51%) were male, 5351 (89%) ever used alcohol, 5065 (85%) were current users, and 2098 (35%) used other drugs. Rates of primary parent smoking were 31% (n=1883) in wave 1 and 30% (n=1829) in wave 2. After adjusting for other exposures known to be associated with teenage substance use, primary parent smoking at waves 1 and 2 was associated with higher odds of teenage alcohol ever use (adjusted odds ratios [aORs] 1·89 [95% CI 1·44–-2·46] at wave 1 and 1·53 [1·20–1·98] at wave 2), current alcohol use (1·88 [1·50–2·36] and 1·59 [1·28–1·97]) and other-drug ever use (1·699 [1·45–1·95] and 1·71 [1·47–1·98]).

Interpretation
Teenagers aged 17–18 years exposed at ages 9 and 13 years to parental smoking were more likely to report significantly higher odds of alcohol and drug use at age 17–18 years. The finding that exposure to parent smoking in childhood increases the risk of teenage alcohol and other drug use suggests a need for interventions aimed at parents who smoke Limitations include potential unmeasured or residual confounders and reliance on self-reported teenage substance use behaviours.

Funding
Royal City of Dublin Hospital Trust, Irish Research Council Government of Ireland Postgraduate Scholarship Programme.

Background
Chronic illness in childhood is associated with worse educational outcomes. The association is usually explained via lowered cognitive development, decreased readiness to learn and school absence. However, this paper examines whether worse psychological adjustment may also play a role.

Methods
We use data from the Growing Up in Ireland study, a cohort study, which collected data on 8,568 nine-year-old children through the Irish national school system using a two-stage sampling method. Maximum likelihood path analytic models are used to assess the direct effect of child chronic illness on reading and maths test scores and the mediating role of emotional and behavioural problems.

Results
In unadjusted analyses, children with a mental and behavioural condition scored 14.5 % points less on reading tests and 16.9 % points less on maths tests than their healthy peers. Children with non-mental and behavioural conditions scored 3 % points less on both tests, a significant difference. Mental and behavioural (OR, 9.58) and other chronic conditions (OR, 1.61) were significantly more likely to have ‘high’ levels of difficulties on the SDQ. Path analysis models showed that the association between chronic illness and educational test scores was completely mediated by emotional and behavioural problems controlling for school absence and bullying by peers.

Conclusions
Child and adolescent chronic illness can have significant effects on educational development and a long-lasting impact on future life-chances. The psychological adjustment of the child is important in mediating the effect of chronic illness on educational outcomes. Interventions should target this developmental pathway.

Background
Energy poverty, typified by cold homes and/or an inability to afford energy bills, presents risks to the mental health of occupants. Parents of young children may be especially susceptible to a mental health toll from energy poverty since they have a significant care obligation and spend much of their day at home.

Methods
Data from the Growing Up in Ireland study inform this longitudinal analysis.

Results
A 1.64 greater odds of maternal depression were estimated for households containing young children characterized by energy poverty [P = 0.000; 95% confidence interval (CI): 1.31–2.05]. For energy poor households with older children (9 years and above), the odds of maternal depression were also higher [odds ratio (OR) 1.74, P = 0.001; 95% CI: 1.27–2.39]. Fathers of young children had greater odds of depression in energy poor households (OR 1.59, P = 0.002; 95% CI: 1.19–2.12), though the deleterious effect on mental health was not statistically significant for fathers of older children.

Conclusions
Energy poverty increases the likelihood of depression in parents. These findings merit policy attention since a mental health burden is in itself important, and more widely, parental well-being can influence child development and outcomes.

Background
Health disparities for children with intellectual disabilities can be challenging to measure due to many other factors that can impact health and healthcare use. The aim of the current study was to use longitudinal cohort data to compare children with intellectual disability (ID) in Ireland between 2006 and 2014 on healthcare utilisation and unmet need, at ages 9 and 13, using a propensity score matching (PSM) approach.

Methods
Using data from the Growing up in Ireland study, PSM was used to identify an appropriate control sample to compare with a sample of children with ID (n = 124). Participants were matched on variables that are known to influence healthcare utilisation to reduce the impact of confounding variables between groups so that differences between the groups can be estimated. Logistic regression was used to estimate effects at ages 9 and 13.

Results
Children with ID were no more likely to have visited a general practitioner or emergency department in the past 12 months than children without ID. They did have a greater likelihood of visiting a doctor in a hospital in the past 12 months and of having an overnight stay in hospital by age 9. Primary caregivers of children with ID were more likely to report unmet health needs at ages 9 and 13.

Conclusions
This approach is a novel means of comparing healthcare use in this population by balancing the impact of other factors that may result in inequities, to which children with ID may be more vulnerable.

Background
Height is regarded as a marker of early-life illness, adversity, nutrition and psychosocial stress, but the extent to which differences in height are determined by early-life socioeconomic circumstances, particularly in contemporary populations, is unclear. This study examined socioeconomic differences in children’s height trajectories from birth through to 21 years of age in four European countries.

Methods
Data were from six prospective cohort studies—Generation XXI, Growing Up in Ireland (infant and child cohorts), Millennium Cohort Study, EPITeen and Cardiovascular Risk in Young Finns Study—comprising a total of 49 492 children with growth measured repeatedly from 1980 to 2014. We modelled differences in children’s growth trajectories over time by maternal educational level using hierarchical models with fixed and random components for each cohort study.

Results
Across most cohorts at practically all ages, children from lower educated mothers were shorter on average. The gradient in height was consistently observed at 3 years of age with the difference in expected height between maternal education groups ranging between −0.55 and −1.53 cm for boys and −0.42 to −1.50 cm for girls across the different studies and widening across childhood. The height deficit persists into adolescence and early adulthood. By age 21, boys from primary educated maternal backgrounds lag the tertiary educated by −0.67 cm (Portugal) and −2.15 cm (Finland). The comparable figures for girls were −2.49 cm (Portugal) and −2.93 cm (Finland).

Conclusions
Significant differences in children’s height by maternal education persist in modern child populations in Europe.

Background
Historically, breastfeeding rates in Ireland have been low compared with international averages. It has been suggested that maternal ethnicity and citizenship may influence breastfeeding rates, with ethnic minorities thought more likely to breast feed.

Aim
The aim of this study is to investigate the association among maternal citizenship, ethnicity, birthplace and breast feeding. It is hypothesised that Irish mothers (identified through Irish citizenship, self-identified Irish ethnicity or Irish birthplace) are less likely to breast feed than non-Irish mothers.

Methods
The study population of Growing Up in Ireland: the National Longitudinal Study of Children was used for this study. Analysis was restricted to 11 092 biological mother and infant pairs with a complete breastfeeding history. Logistic regression analysis was used to estimate ORs and 95% CIs for breast feeding relative to maternal citizenship and ethnicity, controlling for the confounding effects of other maternal variables.

Results
Results indicated that 55.9% (6202 of 11 092) of mothers had initiated breast feeding, with only 7.9% (874 of 11 092) of mothers currently breast feeding their infant (at 9 months of age). Irish citizens (4693 of 9368, 50.0%) were significantly less likely to have initiated breast feeding compared with non-Irish citizens (1503 of 1695, 88.7%). Irish born mothers (4179 of 8627, 48.8%) were also significantly less likely to have initiated breast feeding than mothers born elsewhere (2023 of 2462, 82.2%).

Conclusions
Maternal citizenship and ethnicity appear to be the strongest influencing factors on breastfeeding initiation and duration. However, this raises a possibility that the increase in breastfeeding rates seen recently may be the result of increased immigration into Ireland, rather than the success of policy and research efforts.

Background
Independent associations between screen time (ST)/physical activity (PA) and overweight (OW)/obesity have been demonstrated but little research exists on the role of ST among sufficiently active children.

Purpose
To examine the combined influence of ST and PA on risk of OW/obesity in a nationally representative sample of 9-year-old Irish children.

Methods
The sample in this cross sectional analysis contained 8568 children. Self-report parent data were used to group children into ST and PA categories and related to OW/obesity using forced entry logistic regression.

Results
High ST (> 3 hours/day), bedroom TV and mobile phone ownership increased risk of OW/obesity in high and low active children (P < .05). Low PA (<9 bouts fortnightly) was also associated with OW/obesity. In combined analyses, OW/obesity was lowest in the reference low ST/high PA group with ORs of 1.38, 1.63, and 2.07, respectively, in the low ST/low PA, high ST/high PA, and high ST/low PA groups. Access to electronic media, low socioeconomic status, parental obesity, and not engaging in sports were all related to high ST (P < .05).

Conclusion
This study supports findings that ST is associated with OW/Obesity demonstrating this separately in high and low active children.

Background
Ireland has one of the lowest BF rates in the world. This study investigates the association between breastfeeding and infant health in Ireland.

Methods
A cross-sectional, secondary analysis of data collected from Growing Up in Ireland (GUI): the National Longitudinal Study of Children was conducted. The average morbidity for 2212.

infants exclusively breastfed for at least 90 days (EBF90days) was compared to data for 3987 infants in the non-breastfed (Non-BF) group. Data were weighted using entropy balancing to ensure the comparability of groups. Sensitivity analyses considered alternative definitions of the breastfeeding group.

Results
Infants who were EBF90days were significantly less likely to be admitted to hospital (CI: − 0.06 to − 0.03), spent less nights in hospital (CI: − 0.37 to − 0.11), and were less likely to develop respiratory diseases including asthma (CI: − 0.03 to − 0.01), chest infections (CI: − 0.12 to − 0.08), snuffles/common colds (CI: − 0.07 to − 0.02), ear infections (CI: − 0.08 to − 0.04), eczema (CI: − 0.08 to − 0.04), skin problems (CI: − 0.04 to − 0.00), wheezing or asthma (CI: − 0.06 to − 0.03), vomiting (CI: − 0.03 to − 0.00), and colic (CI: − 0.04 to − 0.01). Further outcomes such as current health of the infant at time of interview (CI: − 0.04 to − 0.00), feeding problems (CI: − 0.04 to − 0.02) and sleeping problems (CI: − 0.02 to − 0.00) indicated a protective effect of EBF90days versus Non-BF. However, these infants were also more likely to fail to gain weight (CI: 0.01 to 0.02) and were at a slightly higher risk of developing nappy rash (CI: 0.00 to 0.02).

Conclusion
Exclusive breastfeeding for 90+ days is associated with protection against childhood morbidity. Given the protective effect of breastfeeding on adverse health effects in infants, policy makers should prioritise policies that support, promote and protect exclusive breastfeeding.

Background
Meeting physical activity and screen time guidelines has been associated with improved health in children. Research has shown that lifestyle behaviours happen in combination and can be tracked into later life. Thus, a complex approach is needed to identify the effects of physical activity and screen time altogether. This study aims to identify clusters of both behaviours in a cohort of Irish 3-year-old children (n = 8833) and determine the association with sociodemographic characteristics and behaviours at age 5 and 7-8.

Methods
Data from the “Growing Up in Ireland” study collected between 2010 and 2016 was used in this study. Two-step cluster analysis was used to understand how physical activity and recreational screen time behaviours group together among 3-year-old children. Binary logistic regressions were conducted to examine if cluster placement at age 3 determined physical activity and recreational screen time behaviours at age 5 and 7-8 years, while controlling for gender of child, gender, age and employment status of the primary caregiver.

Results
Six clusters were identified in 9771 (49.3% female) 3-year-old children with the majority falling into a “High Active & Mixed Screen Time” (23.2%). Those in the “High Active & Mixed Screen Time” cluster at age 3 were more likely to engage in all physical activities reported at age 5 (p < 0.01) and age 7-8 (p < 0.01) when compared to a “Low Active & Screen Time Exceed” cluster. Children categorised in a “Moderate Active & Screen Time Below” and “Moderate Active & Screen Time Exceed” were more likely to engage in the same physical activities at age 5 and 7-8 (p < 0.05 – p < 0.01). However, children in the latter cluster were also more likely (p < 0.05) to play on a computer or tablet device.

Conclusions
This paper highlights the importance of establishing positive health-related behaviours during early childhood, as this predicts future engagement in health-promoting activities. Regardless of screen time level, being part of a cluster with moderate or high levels of physical activity positively influences a child’s future physical activity at age 5 and again at age 7 -8 years. The multiple layers of influence on a child’s development should be leveraged to support the adoption of health-enhancing behaviours.

Background
Orofacial clefts occur when the lips or the roof of the mouth do not fuse properly during the early weeks of pregnancy. There is strong evidence that periconceptional use of folic acid can prevent neural tube defects but its effect on oral clefts has generated debate.

Aim
To identify factors associated with suboptimal periconceptional use of folic acid and its potential effect on oral clefts.

Design and setting
The population-based infant cohort of the national Growing Up in Ireland study, which consists of 11 134 9-month-old infants.

Method
Data collection comprised questionnaires conducted by interviewers with parents in parents’ homes. Characteristics of mothers who did or did not take folic acid before and during pregnancy, as well as the effect of folic acid use on the prevalence of cleft lip and palate were recorded.

Results
The prevalence of cleft lip and palate was 1.98 (95% confidence interval [CI] = 1.31 to 2.99) per 1000 9-month-olds. The odds ratio for cleft lip was 4.36-fold higher (95% CI = 1.55 to 12.30, P = 0.005) for infants of mothers who did not take folic acid during the first 3 months of pregnancy, when compared with those who did have a folate intake during the first trimester. Folic acid use was suboptimal in 36.3% (95% CI = 35.4 to 37.2) of the sample.

Conclusion
These findings support the hypothesis that taking folic acid may partially prevent cleft lip and palate. They are particularly relevant for GPs, because they are usually the first port of call for women before and during early pregnancy.

Keywords
cleft lip, epidemiology, folic acid, general practice, infant

Background
Parental incarceration (PI) is associated with adverse developmental outcomes for children affected. However, research in this area often reports conflicting results with few studies following children across time in non-U.S. populations. Additionally, more research is called for using multi-informant perspectives rather than relying on adult reports of child outcomes alone.

Methods
This study used data from the first two waves of a nationally representative cohort study of 8,568 children aged 9 years and followed up at age 13 living in the Republic of Ireland (2007–2012). Propensity score matching was used to match children who had experienced PI by the age of nine to children who had not experienced PI by sociodemographics and experience of other stressful events. Mental health, as measured by self-concept (Piers-Harris II) and externalizing and internalizing difficulties (strength and difficulties questionnaire), was compared across both groups.

Results
Fifty of the 8,568 children (weighted percentage 0.9%) reported experiencing PI by the age of nine. These children came from more socially disadvantaged homes and were more likely to have experienced other potentially stressful life events. In comparison to a matched sample of children not affected by PI, children affected by PI reported higher levels of anxiety at age nine. Longitudinal analysis indicated these children affected by PI also reported lower levels of happiness at age 13 with higher levels of emotional difficulties reported by their primary caregiver.

Conclusions
Children of incarcerated parents face a greater array of life challenges. PI had an association with child-reported levels of anxiety at age nine. PI also had a medium-term association on caregiver assessments of emotional difficulties of children affected as well child-reported levels of happiness over time.

Background
Parental obesity is a predominant risk factor for childhood obesity. Family factors including socio-economic status (SES) play a role in determining parent weight. It is essential to unpick how shared family factors impact on child weight. This study aims to investigate the association between measured parent weight status, familial socio-economic factors and the risk of childhood obesity at age 9.

Methodology/Principal Findings
Cross sectional analysis of the first wave (2008) of the Growing Up in Ireland (GUI) study. GUI is a nationally representative study of 9-year-old children (N = 8,568). Schools were selected from the national total (response rate 82%) and age eligible children (response rate 57%) were invited to participate. Children and their parents had height and weight measurements taken using standard methods. Data were reweighted to account for the sampling design. Childhood overweight and obesity prevalence were calculated using International Obesity Taskforce definitions. Multinomial logistic regression examined the association between parent weight status, indicators of SES and child weight. Overall, 25% of children were either overweight (19.3%) or obese (6.6%). Parental obesity was a significant predictor of child obesity. Of children with normal weight parents, 14.4% were overweight or obese whereas 46.2% of children with obese parents were overweight or obese. Maternal education and household class were more consistently associated with a child being in a higher body mass index category than household income. Adjusted regression indicated that female gender, one parent family type, lower maternal education, lower household class and a heavier parent weight status significantly increased the odds of childhood obesity.

Conclusions/Significance
Parental weight appears to be the most influential factor driving the childhood obesity epidemic in Ireland and is an independent predictor of child obesity across SES groups. Due to the high prevalence of obesity in parents and children, population based interventions are required.

Background
Physical activity (PA) can reduce young peoples’ risk of depressive symptoms. Associations between PA and depressive symptoms are often investigated over timeframes spanning minutes to weeks. Less is known about whether childhood/adolescent PA can predict depressive symptoms in early adulthood.

Methods
Using a nationally representative sample from Ireland, latent growth mixture modelling was performed to investigate the extent to which different PA trajectories existed from ages 9–17, whether gender, weight status, and socio-economic deprivation at age 9, predicted PA trajectories from ages 9–17, and whether trajectory class membership predicted depressive symptoms at age 20.

Results
A 4-class solution was the best fit to the data (AIC = 52 175.69; BIC = 52 302.69; ssaBIC = 52 245.49; entropy = 1.00). Classes were labelled according to their baseline PA and slope of their trajectory: ‘High-Decreasers’; ‘Moderate-Decreasers’; ‘Moderate-Stable’; and ‘Low-Increasers’. A negative linear association existed between activity trajectory and the likelihood class members were female, overweight or socioeconomically deprived at age 9. The most active class (High-Decreasers) were significantly less likely to report depressive symptoms at age 20 than other classes.

Conclusions
Multiple PA trajectories exist throughout childhood and adolescence although differences in PA levels reduced over time. The most/least active children continued to be the most/least active throughout adolescence. Those most active were least at risk of depressive symptoms in early adulthood. Being female, overweight or experiencing deprivation at age 9 were all risk factors for inactivity throughout adolescence. Findings have implications for public health and PA promotion in young people

Background
Physical activity plays an important role in optimising physical and mental health during childhood, adolescence, and throughout adult life. This study aims to identify individual, family and environmental factors that determine physical activity levels in a population sample of children in Ireland.

Methods
Cross-sectional analysis of the first wave (2008) of the nationally representative Growing Up in Ireland study. A two-stage clustered sampling method was used where national schools served as the primary sampling unit (response rate: 82%) and age eligible children from participating schools were the secondary units (response rate: 57%). Parent reported child physical activity levels and potential covariates (parent and child reported) include favourite hobby, total screen time, sports participation and child body mass index (measured by trained researcher). Univariate and multivariate multinomial logistic regression (forward block entry) examined the association between individual, family and environmental level factors and physical activity levels.

Results
The children (N = 8,568) were classified as achieving low (25%), moderate (20%) or high (55%) physical activity levels. In the fully adjusted model, male gender (OR 1.64 [95% CI: 1.34-2.01]), having an active favourite hobby (OR 1.65 [95% CI: 1.31-2.08]) and membership of sports or fitness team (OR 1.90 [95% CI: 1.48-2.45]) were significantly associated with being in the high physical activity group. Exceeding two hours total screen time (OR 0.66 [95% CI: 0.52-0.85]), being overweight (OR 0.41 [95%CI: 0.27-0.61]; or obese (OR 0.68 [95%CI: 0.54-0.86]) were significantly associated with decreased odds of being in the high physical activity group.

Conclusions
Individual level factors appear to predict PA levels when considered in the multiple domains. Future research should aim to use more robust objective measures to explore the usefulness of the interconnect that exists across these domains. In particular how the family and environmental settings could be useful facilitators for consistent individual level factors such as sports participation.

Background
Population-based studies provide important data to inform policy and service planning for vulnerable children in society. The aim of this study was to characterise social and educational circumstances and self-concept among a nationally representative sample of 13 year olds with developmental disabilities in Ireland.

Methods
A cross-sectional, secondary analysis of data collected from the Growing Up in Ireland (GUI) study was conducted. Descriptive statistics were used to calculate the reported prevalence of disabilities as reported by parents. Differences across the groups (those with and without disabilities) were analysed in relation to gender, socio-economic and school factors. Special education support received in school was described. The association between low self-concept scores (as measured by the Piers Harris Self-Concept Scales 2) and disability type was examined by use of multi-level logistic regression.

Results
Seventeen percent (17.36%) of the sample was reported to have a diagnosis of one or more developmental disabilities. Those with a disability were more likely to live in poorer households, have poorer health status, to experience more episodes of bullying at school, and to have more negative views of school (p<0.05) than their typically-developing peers.

Forty nine percent of children with developmental disabilities were not receiving support in school as reported by parents. Discrepancies in the nature of support received were identified across disability types. Adjusting for individual and school level factors, a disability diagnosis was associated with increased odds of low self-concept scores on three of five self-concept domains. Further associations were identified which differed across disability type.

Conclusions
The findings show that 13 year olds with a disability in Ireland have complex social and educational needs. Findings also suggest significant levels of unmet educational need across this age group. Apparent inequities in access to support in school require further investigation. Reliable measures to provide robust prevalence figures about childhood disabilities in Ireland are needed.

Background
Poverty is associated with poor outcomes, yet exposure to distinct poverty trajectories in early childhood is not well understood.

Objective
To understand the prevalence of different trajectories of household poverty and their association with mid-childhood and mother indicators of physical health and psychopathology in Ireland.

Methods
We used a nationally representative, prospective cohort (Growing Up in Ireland–Infant Cohort). Household poverty included lowest third income decile, subjective poverty and material deprivation when children were aged 9 months, and 3, 5, 9 years. We used group-based multitrajectory cluster modelling to classify trajectories of poverty. Using multivariable logistic regression, adjusted with separate child and mother confounders, we assessed the association of poverty trajectories from 9 months to 9 years with child outcomes (overweight, any longstanding illness and psychopathology) at age 9 years and the same poverty trajectories over the same 9-year period with mother outcomes (overweight, any longstanding illness and depression).

Results
Of 11 134 participants, 4 trajectories were identified: never in poverty (43.1%), material/subjective>monetary poverty (16.1%), monetary>material poverty (25.6%) and persistent poverty (15.2%). Children in persistent poverty compared with those in never in poverty experienced higher odds of being overweight at 9 years (adjusted OR (aOR) 1.70, 95% CI 1.34, 2.16), having a longstanding illness (aOR 1.51, 95% CI 1.20, 1.91), and psychopathology (aOR 2.06, 95% CI 1.42, 2.99). The outcomes for primary parents (99.7% were mothers) were as follows: having higher odds of being overweight (aOR 1.49, 95% CI 1.16, 1.92), having a longstanding illness (aOR 2.13, 95% CI 1.63, 2.79), and depression (aOR 3.54, 95% CI 2.54, 4.94).

Conclusions
Any poverty trajectory was associated with poorer psychopathology and physical well-being in late childhood for children and their mothers in Ireland.

Background
Poverty is associated with poor outcomes, yet exposure to distinct poverty trajectories in early childhood is not well understood.

Objective
To understand the prevalence of different trajectories of household poverty and their association with mid-childhood and primary-parent(mother) indicators of physical health and psychopathology in Ireland.

Methods
We used a nationally representative, prospective cohort (Growing-up-in-Ireland– Infant-Cohort). Household poverty included lowest third income decile, subjective poverty and material deprivation when children were aged 9-months(m),3,5,9-years(y). We used group based multi-trajectory-cluster-modelling to classify trajectories of poverty. Using multivariate logistic regression, adjusted with separate child and mother confounders, we assessed the association of poverty trajectories from 9m to 9y with child outcomes (overweight, any longstanding illness and psychopathology) at age 9y and the same poverty trajectories over the same 9y period with mother outcomes (overweight, any longstanding illness and depression).

Results
Of 11,134 participants, four trajectories were identified: never-in-poverty (43.1%), material/subjective>monetary-poverty (16.1%), monetary>material-poverty (25.6%), and persistent-poverty (15.2%). Children in persistent-poverty compared with never in poverty experienced higher odds of being overweight at 9y (adjusted odds ratio aOR 1.70,95% CI 1.34, 2.16), having a longstanding illness (aOR 1.51,95% CI 1.20, 1.91) and psychopathology (aOR 2.06,95% CI 1.42, 2.99). The outcomes for primary parent (99.7% were mothers) had higher odds of being overweight (aOR 1.49,95% CI 1.16, 1.92), having a longstanding illness (aOR 2.13,95% CI 1.63, 2.79), and depression (aOR 3.54,95% CI 2.54, 4.94).

Conclusions
Any poverty trajectory was associated with poorer psychopathology and physical wellbeing in late childhood for children and their mothers in Ireland.

What is already known on this subject?
Poverty is understood as having both objective (e.g. low household income) and subjective dimensions (e.g., perception of being poor relative to others, poverty related anxiety). Evidence highlights the association between child poverty exposure and child and mother wellbeing outcomes.

What this study adds?
Our study examined predicted trajectories of multi-dimensional poverty and child and mother outcomes using a large national cohort. We identified that any poverty trajectory in childhood had a higher odds of being associated with poor well-being outcomes.

How this study might affect research, practice or policy?
This study highlights the need for strategies to ameliorate any poverty exposure as all poverty trajectories resulted in poorer wellbeing outcomes. Strategies should be considered to ameliorate any poverty exposure in early childhood (e.g., school based resourcing).

Background
Preventing child mental health problems and child obesity have been recognized as public health priorities. The aim of the present study was to examine whether being breastfed (at all or exclusively) in infancy was a predictor of mental well-being and protective against risk of obesity at age 9.

Methods
Cross-sectional data from a large, nationally representative cohort study in the Republic of Ireland was used (n = 8357). Data on breastfeeding were retrospectively recalled. Child mental well-being was assessed using a parent-completed Strengths and Difficulties Questionnaire (SDQ). Child’s height and weight were measured using scientifically calibrated instruments.

Results
Logistic regression analyses indicated that, after controlling for a wide range of potential confounding variables, being breastfed in infancy was associated with a 26% (P < 0.05) reduction in the risk of an abnormal SDQ score at 9 years. Being breastfed remained a significant predictor of child mental well-being when child obesity was controlled for, indicating that being breastfed, independent of child obesity, is a predictor of child mental well-being. The results of a second logistic regression indicated that, after controlling for a wide range of potential confounding variables, being breastfed for between 11 and 25 weeks was associated with a 36% (P < 0.05) reduction in the risk of obesity at 9 years, while being breastfed for 26 weeks or longer was associated with a 48% (P < 0.01) reduction in the risk of obesity at 9 years.

Conclusions
Breastfeeding in infancy may protect against both poor mental well-being and obesity in childhood.