Prenatal determinants of depressive symptoms in childhood: Evidence from Growing Up in New Zealand.

BACKGROUND: Young people who experience depression are at an increased risk of adverse psychosocial and developmental outcomes that can persist over the lifecourse. Identifying maternal prenatal risk factors that may contribute to childhood depressive symptoms can be useful when considering mental health intervention. METHODS: The current study included 3,925 children from the Growing Up in New Zealand (GUiNZ) study who had complete data for self-reported depressive symptoms and mothers' antenatal information. Depressive symptoms were measured at age 8 using the Centre for Epidemiological Studies Depression Scale for Children (CESD-10) short form questionnaire. Hierarchical linear regression was used to determine the relationship between prenatal factors and depressive symptoms at age 8. RESULTS: When controlling for sociodemographic characteristics, our hierarchical linear regression revealed that the most significant maternal prenatal predictors of high depressive symptoms at age 8 were maternal perceived stress, smoking during pregnancy, body mass index (BMI) in the overweight/obese range, and paracetamol intake. LIMITATIONS: One limitation with the current study was a reduction in the sample due to attrition. This may have affected our statistical power, reflected in our modest effect sizes. The sample remained both socioeconomically and ethnically diverse, however our results should be interpreted with respect to the sample and not the whole New Zealand population. CONCLUSIONS: A combination of maternal mental health and lifestyle factors contribute to depressive symptoms for children, possibly through foetal programming. Our results emphasise the importance of mental and physical health support for expectant mothers.

An index measuring adherence to New Zealand Infant Feeding Guidelines has convergent validity with maternal socio-demographic and health behaviours and with children's body size.

Using data from a nationally generalisable birth cohort, we aimed to: (i) describe the cohort's adherence to national evidence-based dietary guidelines using an Infant Feeding Index (IFI) and (ii) assess the IFI's convergent construct validity, by exploring associations with antenatal maternal socio-demographic and health behaviours and with child overweight/obesity and central adiposity at age 54 months. Data were from the Growing Up in New Zealand cohort (n 6343). The IFI scores ranged from zero to twelve points, with twelve representing full adherence to the guidelines. Overweight/obesity was defined by BMI-for-age (based on the WHO Growth Standards). Central adiposity was defined as waist-to-height ratio > 90th percentile. Associations were tested using multiple linear regression and Poisson regression with robust variance (risk ratios, 95 % CI). Mean IFI score was 8·2 (sd 2·1). Maternal characteristics explained 29·1 % of variation in the IFI score. Maternal age, education and smoking had the strongest independent relationships with IFI scores. Compared with children in the highest IFI tertile, girls in the lowest and middle tertiles were more likely to be overweight/obese (1·46, 1·03, 2·06 and 1·56, 1·09, 2·23, respectively) and boys in the lowest tertile were more likely to have central adiposity (1·53, 1·02, 2·30) at age 54 months. Most infants fell short of meeting national Infant Feeding Guidelines. The associations between IFI score and maternal characteristics, and children's overweight/obesity/central adiposity, were in the expected directions and confirm the IFI's convergent construct validity.

A prediction model for childhood obesity in New Zealand.

Several early childhood obesity prediction models have been developed, but none for New Zealand's diverse population. We aimed to develop and validate a model for predicting obesity in 4-5-year-old New Zealand children, using parental and infant data from the Growing Up in New Zealand (GUiNZ) cohort. Obesity was defined as body mass index (BMI) for age and sex ≥ 95th percentile. Data on GUiNZ children were used for derivation (n = 1731) and internal validation (n = 713). External validation was performed using data from the Prevention of Overweight in Infancy Study (POI, n = 383) and Pacific Islands Families Study (PIF, n = 135) cohorts. The final model included: birth weight, maternal smoking during pregnancy, maternal pre-pregnancy BMI, paternal BMI, and infant weight gain. Discrimination accuracy was adequate [AUROC = 0.74 (0.71-0.77)], remained so when validated internally [AUROC = 0.73 (0.68-0.78)] and externally on PIF [AUROC = 0.74 [0.66-0.82)] and POI [AUROC = 0.80 (0.71-0.90)]. Positive predictive values were variable but low across the risk threshold range (GUiNZ derivation 19-54%; GUiNZ validation 19-48%; and POI 8-24%), although more consistent in the PIF cohort (52-61%), all indicating high rates of false positives. Although this early childhood obesity prediction model could inform early obesity prevention, high rates of false positives might create unwarranted anxiety for families.

Multimorbidity in Early Childhood and Socioeconomic Disadvantage: Findings From a Large New Zealand Child Cohort.

OBJECTIVE: In contrast with multimorbidity during adulthood, the relationship of childhood multimorbidity with socioeconomic position (SEP) is poorly understood. We aimed to describe early childhood multimorbidity and investigate the relationship of this with SEP. METHODS: Within a diverse prospective child cohort study, we determined associations of SEP with multimorbidity (defined as the presence of 2 or more chronic conditions) at age 2 years. Maternal SEP was ranked into 5 categories using an index constructed from variables collected antenatally describing maternal education, employment, financial stress, beneficiary status, housing tenure, overcrowding, and residential mobility. Missing values were handled using multiple imputation with chained equations. Independent associations of SEP with multimorbidity were described using adjusted odds ratios (OR) and 95% confidence intervals (CI). RESULTS: Of the 6822 women and 6853 children who were enrolled into the cohort study, 5737 (84%) mother-child dyads had complete antenatal data and were interviewed at age 2 years. Of these 5737, for 3826 (67%) dyads, there were complete data for all variables. Multimorbidity was present in 374/3838 (9.7%) of the cohort children. After multiple imputation and adjustment for maternal ethnicity, smoking, poor health, depressive symptoms, and child gender, the odds of multimorbidity being present were increased for children of mothers in the most (OR 1.74, 95% CI 1.16-2.59) and second most (OR 1.43, 95% CI 1.00-2.04) versus the least disadvantaged group. CONCLUSION: The odds of multimorbidity are increased for children whose mothers have lower SEP. Cumulative socioeconomic disadvantage increases the potential for a chronic illness trajectory to develop in early childhood.

Antenatal determinants of early childhood talking delay and behavioural difficulties.

The determinants of talking delay alone or its comorbidity with behavioural difficulties was examined in 5768 two-year-old members of the Growing Up in New Zealand longitudinal study. Using the MacArthur-Bates Communicative Development inventories and the total difficulties score from the preschool Strengths and Difficulties Questionnaire, a composite measure was created so that children were categorised as showing no language or behavioural concerns (72.5%), behavioural only difficulties (6.1%), language only difficulties (18.1%), and comorbid language and behavioural difficulties (3.3%). Analyses revealed that antenatal factors such as maternal perceived stress, inadequate folate intake, vitamin intake, alcohol consumption during the first trimester and maternal smoking all had a significant effect on child outcomes. In particular, low multivitamin intake and perceived stress during pregnancy were associated with coexisting language and behavioural difficulties. These findings support international research in showing that maternal factors during pregnancy are associated with developmental outcomes in the early childhood period, and demonstrate these associations within a NZ context. Interventions which address maternal stress management and health behaviours during pregnancy could be beneficial to offspring development.

A longitudinal study of antenatal and perinatal risk factors in early childhood cognition: Evidence from Growing Up in New Zealand.

BACKGROUND: Poor maternal health, disadvantageous exposures during pregnancy and unfavourable perinatal events are associated with adverse trajectories in offspring cognitive development. AIM: To examine longitudinal associations between antenatal maternal, perinatal and maternal health characteristics and children's early cognitive development across executive control, motor ability and receptive language domains. STUDY DESIGN, SUBJECTS AND OUTCOME MEASURES: Analyses comprised interview and observational data from 4587 children and their mothers enrolled in the longitudinal Growing Up in New Zealand cohort study. Children's executive control (Luria hand clap task), motor skills (mothers' report) and receptive language ability (Peabody Picture Vocabulary Test) were assessed at age 4.5 years. Multivariate logistic regression analyses were conducted, controlling for sociodemographic factors. RESULTS: Smoking pre- and during pregnancy, no folate intake during first trimester and low birth weight were risk factors for poorer executive control. Perceived stress during pregnancy, no folate intake during first trimester and low birth weight were all risk factors for poorer motor ability. Smoking pre-pregnancy, antenatal anxiety and no folate intake during first trimester were risk factors for poorer receptive language ability. CONCLUSION: Adverse ante- and perinatal environments are associated with poorer executive control, motor and receptive language abilities in early childhood. Improving maternal education and support especially for more disadvantaged mothers during pregnancy may reduce the potential deleterious impact of adverse ante- and perinatal conditions on children's early cognition.

Do childcare menus meet nutrition guidelines? Quantity, variety and quality of food provided in New Zealand Early Childhood Education services.

OBJECTIVE: To describe food provision and evaluate menus in New Zealand childcare services, determining associations with service characteristics and/or cost of menu. METHODS: Licensed services in three regions of New Zealand participated in an online survey, uploading a weekly menu where applicable. Menus were scored for compliance with guidelines on quantity, variety and quality of foods served. Bivariate and multivariate associations between menu score and service characteristics were analysed. RESULTS: A total of 257 services participated (30% of 847 services invited). Food was provided daily in 56%, with 34% providing lunch and snacks daily. Of the 57 full menus analysed, only three (5%) met all 10 scoring criteria (mean score of 6.8/10). Higher menu scores were statistically associated with employing a cook, high and low (not medium) neighbourhood deprivation, the Heart Foundation's Healthy Heart Award program; there was no association with food costs. The Healthy Heart Award remained statistically associated with higher menu score after adjustment for other service characteristics. CONCLUSION: Most menus did not meet current nutrition guidelines for quantity, variety, and limiting 'sometimes' and 'occasional' foods. Implications for public health: This study provides a baseline for monitoring menu compliance in New Zealand and evidence for nutrition promotion and menu improvement programmes in early education.

Maternal health in pregnancy and associations with adverse birth outcomes: Evidence from Growing Up in New Zealand.

OBJECTIVE: To examine prospectively multiple indicators of pregnancy health and associations with adverse birth outcomes within a large, diverse sample of contemporary women. DESIGN: A cohort of pregnant women who gave birth during 2009-10. POPULATION: We enrolled a sample of 6822 pregnant New Zealand (NZ) women: 11% of all births in NZ during the recruitment period. METHODS: We analysed a number of maternal health indicators and behaviours during pregnancy in relation to birth outcomes using multivariable logistic regression. Associations were described using adjusted odds ratios and 95% confidence intervals. MAIN OUTCOME MEASURES: Three birth outcomes, low birth weight (LBW), pre-term birth (PTB) and delivery type, were measured via linkage with maternity hospital perinatal databases. Small for gestational age (SGA) was then defined as below the 10th percentile by week of gestation. RESULTS: Modelling of birth outcomes after adjusting for confounders indicated patterns of increased risk of LBW and PTB for women who smoke, have elevated pre-pregnancy body mass index (BMI), or with insufficient pregnancy weight gain. SGA was associated with maternal smoking, alcohol use, insufficient weight gain and nausea and vomiting during pregnancy. Risk of caesarean section was associated with having a diagnosed illness before pregnancy, elevated BMI, greater pregnancy weight gain and less pregnancy exercise. Number of risk factor variables were then used to model birth outcomes. Women with multiple risk factors were at increased risk compared with those who had no risk factors. CONCLUSIONS: Women with multiple health risks are at particular risk of adverse birth outcomes.

Internal living environment and respiratory disease in children: findings from the Growing Up in New Zealand longitudinal child cohort study.

BACKGROUND: The incidence of early childhood acute respiratory infections (ARIs) has been associated with aspects of the indoor environment. In recent years, public awareness about some of these environmental issues has increased, including new laws and subsequent changes in occupant behaviours. This New Zealand study investigated current exposures to specific risk factors in the home during the first five years of life and provided updated evidence on the links between the home environment and childhood ARI hospitalisation. METHODS: Pregnant women (n = 6822) were recruited in 2009 and 2010, and their 6853 children created a child cohort that was representative of New Zealand births from 2007-10. Longitudinal data were collected through face-to-face interviews and linkage to routinely collected national datasets. Incidence rates with Poisson distribution confidence intervals were computed and Cox regression modelling for repeated events was performed. RESULTS: Living in a rented dwelling (48%), household crowding (22%) or dampness (20%); and, in the child's room, heavy condensation (20%) or mould or mildew on walls or ceilings (13%) were prevalent. In 14% of the households, the mother smoked cigarettes and in 30%, other household members smoked. Electric heaters were commonly used, followed by wood, flued gas and unflued portable gas heaters. The incidence of ARI hospitalisation before age five years was 33/1000 person-years. The risk of ARI hospitalisation was higher for children living in households where there was a gas heater in the child's bedroom: hazard ratio for flued gas heater 1.69 (95% CI: 1.21-2.36); and for unflued gas heater 1.68 (95% CI: 1.12-2.53); and where a gas heater was the sole type of household heating (hazard ratio: 1.64 (95% CI: 1.29-2.09)). The risk was reduced in households that used electric heaters (Hazard ratio: 0.74 (95% CI: 0.61-0.89)) or wood burners (hazard ratio: 0.79 (95% CI: 0.66-0.93)) as a form of household heating. The associations with other risk factors were not significant. CONCLUSIONS: The risk of early childhood ARI hospitalisation is increased by gas heater usage, specifically in the child's bedroom. Use of non-gas forms of heating may reduce the risk of early childhood ARI hospitalisation.

Dietary Patterns in Pregnancy in New Zealand-Influence of Maternal Socio-Demographic, Health and Lifestyle Factors.

Exploration of dietary pattern associations within a multi-ethnic society context has been limited. We aimed to describe dietary patterns of 5664 pregnant women from the Growing Up in New Zealand study, and investigate associations between these patterns and maternal socio-demographic, place of birth, health and lifestyle factors. Participants completed a food frequency questionnaire prior to the birth of their child. Principal components analysis was used to extract dietary patterns and multivariable analyses used to determine associations. Four dietary components were extracted. Higher scores on, 'Junk' and 'Traditional/White bread', were associated with decreasing age, lower educational levels, being of Pacific or Maori ethnicity and smoking. Higher scores on, 'Health conscious' and 'Fusion/Protein', were associated with increasing age, better self-rated health, lower pre-pregnancy body mass index (BMI) and not smoking. Higher scores on 'Junk' and 'Health conscious' were associated with being born in New Zealand (NZ), whereas higher scores on 'Fusion/Protein' was associated with being born outside NZ and being of non-European ethnicity, particularly Asian. High scores on the 'Health conscious' dietary pattern showed the highest odds of adherence to the pregnancy dietary guidelines. In this cohort of pregnant women different dietary patterns were associated with migration, ethnicity, socio-demographic characteristics, health behaviors and adherence to dietary guidelines.

Childhood socioeconomic position, educational attainment, and adult cardiovascular risk factors: the Aberdeen children of the 1950s cohort study.

OBJECTIVES: We assessed the associations of childhood socioeconomic position with cardiovascular disease risk factors (smoking, binge alcohol drinking, and being overweight) and examined the roles of educational attainment and cognitive functioning in these associations. METHODS: Data were derived from a cohort study involving 7184 individuals who were born in Aberdeen, Scotland, between 1950 and 1956; had detailed records on perinatal characteristics, childhood anthropometry, and cognitive functioning; and responded to a mailed questionnaire when they were aged 45 to 52 years. RESULTS: Strong graded associations existed between social class at birth and smoking, binge drinking, and being overweight. Adjustment for educational attainment completely attenuated these associations. However, after control for adult social class, adult income and other potential confounding or mediating factors, some association remained. CONCLUSIONS: Educational attainment is an important mediating factor in the relation between socioeconomic adversity in childhood and smoking, binge drinking, and being overweight in adulthood.