The Unique Extended Selection Cohorts Design for the Evaluation of the School-Based Jump-In Intervention on Dietary Habits: A Study Protocol.

Background: To promote healthy dietary and physical activity behaviour among primary school children, the city of Amsterdam structurally implements the school-based Jump-in intervention in over half of its primary schools. Previously shown to be effective in stimulating physical activity and outside recess play, our study is the first to evaluate Jump-in's effect on children's dietary behaviour. Evaluating the effectiveness and implementation process of an intervention in a real-life setting requests an alternative study design. Methods: we chose a mixed-methods, quasi-experimental Extended Selection Cohorts design to evaluate Jump-in's effectiveness and implementation process. Children and parents from the first ten primary schools that enrolled in the programme in 2016-2017 were invited to participate. The primary outcomes were children's dietary behaviour and behavioural determinants, assessed by child and parent questionnaires, and photographs of the food and drinks children brought to school. Process indicators, contextual factors and satisfaction with the programme were assessed by interviews with health promotion professionals, school principals, school project coordinators, and teachers; focus group discussions with parents and children; and document analysis. Discussion: Conducting research in a real-life setting is accompanied by methodological challenges. Using an Extended Selection Cohorts design provides a valuable alternative when a Randomized Controlled design is not feasible.

Ethnicity and socioeconomic status are related to dietary patterns at age 5 in the Amsterdam born children and their development (ABCD) cohort.

BACKGROUND: Health inequalities are already present at young age and tend to vary with ethnicity and socioeconomic status (SES). Diet is a major determinant of overweight, and studying dietary patterns as a whole in relation to overweight rather than single nutrients or foods has been suggested. We derived dietary patterns at age 5 and determined whether ethnicity and SES were both related to these dietary patterns. METHODS: We analysed 2769 validated Food Frequency Questionnaires filled in by mothers of children (5.7 ± 0.5y) in the Amsterdam Born Children and their Development (ABCD) cohort. Food items were reduced to 41 food groups. Energy adjusted intake per food group (g/d) was used to derive dietary patterns using Principal Component Analysis and children were given a pattern score for each dietary pattern. We defined 5 ethnic groups (Dutch, Surinamese, Turkish, Moroccan, other ethnicities) and 3 SES groups (low, middle, high, based on maternal education). Multivariate ANOVA, with adjustment for age, gender and maternal age, was used to test potential associations between ethnicity or SES and dietary pattern scores. Post-hoc analyses with Bonferroni adjustment were used to examine differences between groups. RESULTS: Principal Component Analysis identified 4 dietary patterns: a snacking, full-fat, meat and healthy dietary pattern, explaining 21% of the variation in dietary intake. Ethnicity was related to the dietary pattern scores (p < 0.01): non-Dutch children scored high on snacking and healthy pattern, whereas Turkish children scored high on full-fat and Surinamese children on the meat pattern. SES was related to the snacking, full-fat and meat patterns (p < 0.01): low SES children scored high on the snacking and meat pattern and low on the full-fat pattern. CONCLUSIONS: This study indicates that both ethnicity and SES are relevant for dietary patterns at age 5 and may enable more specific nutrition education to specific ethnic and low socioeconomic status target groups.

Seven-year time trends in energy balance-related behaviours according to educational level and ethnic background among 14-year-old adolescents.

OBJECTIVE: To assess seven-year time trends in energy balance-related behaviours in 14-year-old adolescents living in an urban area and to examine the influence of educational level and ethnicity on these time trends. DESIGN: Second grade students (mean age 13·6 years) filled in questionnaires about the energy balance-related behaviours of breakfast consumption, fruit and vegetable consumption, physical activity and screen-time behaviour from school years 2006-2007 to 2012-2013. Energy balance-related behaviours were dichotomized and logistic regression analyses were used to examine time trends in healthy energy balance-related behaviours, including interaction terms for educational level and ethnicity. SETTING: Secondary schools in Amsterdam, the Netherlands. SUBJECTS: Per school year, 2185-3331 children participated. The total sample included 19 244 students of Dutch, Surinamese, Turkish and Moroccan ethnic background. RESULTS: A significant linear increase was found for positive screen-time behaviour (<2 h/d; OR per year=1·04; 95 % CI 1·03, 1·06). For daily vegetable consumption a non-linear negative trend was observed (school year 2012-2013 v. 2006-2007: OR=0·90; 95 % CI 0·80, 1·00). Time trends in screen time were significantly different across educational levels (P-interaction=0·002) and ethnic backgrounds (P<0·001), as were time trends in daily fruit consumption (P=0·017 and P=0·018, respectively) and, for ethnicity, trends in daily vegetable consumption (P<0·001). CONCLUSIONS: The increase in positive screen-time behaviour is a positive finding. However, discouraging screen time and promoting other healthy behaviours, more specifically daily fruit and vegetable consumption, remain important particularly among adolescents enrolled in pre-vocational education and of non-Dutch ethnic background.

Exploring educational disparities in risk of preterm delivery: a comparative study of 12 European birth cohorts.

BACKGROUND: An association between education and preterm delivery has been observed in populations across Europe, but differences in methodology limit comparability. We performed a direct cross-cohort comparison of educational disparities in preterm delivery based on individual-level birth cohort data. METHODS: The study included data from 12 European cohorts from Denmark, England, France, Lithuania, the Netherlands, Norway, Italy, Portugal, and Spain. The cohorts included between 2434 and 99 655 pregnancies. The association between maternal education and preterm delivery (22-36 completed weeks of gestation) was reported as risk ratios, risk differences, and slope indexes of inequality with 95% confidence intervals (CIs). RESULTS: Singleton preterm live delivery proportion varied between 3.7% and 7.5%. There were large variations between the cohorts in the distribution of education and maternal characteristics. Nevertheless, there were similar educational differences in risk of preterm delivery in 8 of the 12 cohorts with slope index of inequality varying between 2.2 [95% CI 1.1, 3.3] and 4.0 [95% CI 1.4, 6.6] excess preterm deliveries per 100 singleton deliveries among the educationally most disadvantaged, and risk ratio between the lowest and highest education category varying from 1.4 [95% CI 1.1, 1.8] to 1.9 [95% CI 1.2, 3.1]. No associations were found in the last four cohorts. CONCLUSIONS: Educational disparities in preterm delivery were found all over Europe. Despite differences in the distributions of education and preterm delivery, the results were remarkably similar across the cohorts. For those few cohorts that did not follow the pattern, study and country characteristics did not explain the differences.

[Ethnic differences in uptake of professional maternity care assistance]. / Etnische verschillen in het gebruik van kraamzorg.

OBJECTIVE: To examine the ethnic differences in the uptake of professional maternity care assistance (MCA) in the Netherlands, and the factors that may explain these differences. Additionally the effect of MCA on health risk behaviour around infants is examined. DESIGN: Questionnaire survey. METHOD: Questionnaire data from 3967 mothers from the ABCD study (Amsterdam Born Children and their Development) included during pregnancy in 2003-2004, were used. We examined the explanatory role of ethnicity, age, socioeconomic status, mastery of the Dutch language, parity, housing situation and place of giving birth on MCA uptake, and the effect of MCA uptake on health risk behaviour around infants, such as smoking indoors, infant sleep behaviour, infant nutrition, and response to infant crying. RESULTS: Mothers of non-Western origin less often used MCA than Dutch mothers (Ghanaian: 70%; Turkish: 75%; Moroccan: 79%; Surinamese: 81%; Dutch Caribbean: 85% vs. Dutch: 95%). Higher educational level, better mastery of the Dutch language, having a paid job and home delivery were all independently associated with the uptake of MCA, and also partially explained ethnic differences in the uptake of MCA. Mothers who received MCA more often breastfed, more often gave vitamin K when not breastfeeding, and more often lived in smoke-free homes. The protective effect of MCA was stronger for non-Western mothers than for Dutch mothers. CONCLUSION: Mothers of non-Western origin make less use of professional MCA. Given that the use of MCA is associated with a less risk behaviour around infants, efforts should be made to improve the accessibility of professional MCA for mothers of non-Western origin.

Low maternal education is associated with increased growth velocity in the first year of life and in early childhood: the ABCD study.

UNLABELLED: The objective of this study is first to examine the relation of maternal education and growth velocity during the first year of life and early childhood (1-5 years). The second objective is to determine the potential explanatory role of standardized birth weight, maternal smoking during pregnancy, maternal prepregnancy body mass index (BMI), and infant feeding practice in this relation. We used longitudinal growth data of 1,684 participants with Dutch ethnicity participating in a population-based cohort study (Amsterdam Born Children and their Development study). Growth velocity of weight and of weight-for-length were calculated by subtracting the weight and weight-for-length standard deviation scores (SDS), respectively of two time periods. In the first year of life, children with low-educated mothers had an increase in SDS of 0.26 (95 % confidence interval (CI) 0.08-0.45) for weight compared to children with high-educated mothers. In early childhood, children with low-educated mothers had a 0.27 SDS (95 % CI 0.11-0.42) increase for weight-for-length, compared to children with high-educated mothers. Using path analysis, these inequalities could partly be explained by maternal smoking, duration of breastfeeding, maternal age, and maternal BMI. CONCLUSION: Children with low-educated mothers had an increased weight gain during the first year of life and an increased weight-for-length gain in early childhood compared to children with high-educated mothers. Although underlying mechanisms were not completely clarified, an optimal duration of breastfeeding, cessation of maternal smoking, and reduction of maternal BMI seem to reduce these educational inequalities in early growth and possible adverse consequences of accelerated growth.

Smoking overrules many other risk factors for small for gestational age birth in less educated mothers.

BACKGROUND: Although there is convincing evidence for the association between small for gestational age (SGA) and socioeconomic status (SES), it is not known to what extent explanatory factors contribute to this association. AIM: To examine to what extent risk factors could explain educational inequalities in SGA. STUDY DESIGN: In this study fully completed data were available for 3793 pregnant women of Dutch origin from a population-based cohort (ABCD study). Path-analysis was conducted to examine the role of explanatory factors in the relation of maternal education to SGA. RESULTS: Low-educated pregnant women had a higher risk of SGA offspring compared to the high-educated women (OR 1.98, 95% CI 1.35-2.89). In path-analysis, maternal cigarette smoking and maternal height explained this association. Maternal age, hypertension, chronic disease, late entry into antenatal care, neighborhood income, underweight, environmental cigarette smoking, drug abuse, alcohol use, caffeine intake, fish intake, folic acid intake, anxiety, and depressive symptoms did not play a role in the association between maternal education and SGA birth. CONCLUSION: Among a large array of potential factors, the elevated risk of SGA birth among low-educated women appeared largely attributable to maternal smoking and to a lesser extent to maternal height. To reduce educational inequalities more effort is required to include low-educated women especially in prenatal intervention programs such as smoking cessation programs instead of effort into reducing other SGA-risk factors, though these factors might still be relevant at the individual level.

Explaining socioeconomic inequalities in childhood blood pressure and prehypertension: the ABCD study.

Much remains to be understood about the socioeconomic inequalities in hypertension that continue to exist. We investigated the association of socioeconomic status with blood pressure and prehypertension in childhood. In a prospective cohort, 3024 five- to six-year-old children had blood pressure measurements and available information on potential explanatory factors, namely birth weight, gestational age, smoking during pregnancy, pregnancy-induced hypertension, familial hypertension, maternal body mass index, breastfeeding duration, domestic tobacco exposure, and body mass index. The systolic and diastolic blood pressures of children from mid-educated women were 1.0-mm Hg higher (95% CI, 0.4-1.7) and 0.9-mm Hg higher (95% CI, 0.3-1.4), and the blood pressures of children with low-educated women were 2.2-mm Hg higher (95% CI, 1.4-3.0) and 1.7-mm Hg higher (95% CI, 1.1-2.4) compared with children with high-educated women. Children with mid- (odds ratio, 1.50; 95% CI, 1.18-1.92) or low-educated mothers (odds ratio, 1.80; 95% CI, 1.35-2.42) were more likely to have prehypertension compared with children with high-educated mothers. Using path analyses, birth weight, breastfeeding duration, and body mass index were determined as having a role in the association of maternal education with offspring blood pressure and prehypertension. The socioeconomic gradient in hypertension appears to emerge from childhood as the results show a higher blood pressure and more prehypertension in children from lower socioeconomic status families. Socioeconomic disparities could be reduced by improving 3 factors in particular, namely birth weight, breastfeeding duration, and body mass index, but other factors might also play a role.

Association between body size and blood pressure in children from different ethnic origins.

OBJECTIVE: To assess associations between body size and blood pressure in children (5-6 years) from different ethnic origins. METHOD: Five ethnic groups of the ABCD cohort were examined: Dutch (n=1 923), Turkish (n=99), Moroccan (n=187), Black-African (n=67) and Black-Caribbean (n=121). Data on body-mass-index (BMI), waist-to-height ratio (WHtR), fat-mass-index (FMI), and systolic blood pressure (SBP) and diastolic blood pressure (DBP), were collected. Linear regression analysis with restricted cubic splines was used to examine non-linear associations between body size and blood pressure, adjusted for age, sex, height and birth weight. RESULTS: Ethnic differences were found in associations of BMI with SBP and DBP (SBP: p=0.001 and DBP: p=0.01) and FMI with SBP (p=0.03). BMI and FMI had a relatively large positive association with SBP in Turkish children (BMI: ß=2.46mmHg; 95%CI:1.20-3.72; FMI: ß=2.41mmHg; 95%CI:1.09-3.73) compared to Dutch (BMI: ß=1.31mmHg; 95%CI:0.71-1.92; FMI: ß=0.84mmHg; 95%CI:0.23-1.45). Black-Caribbean and Moroccan children showed high blood pressure with low BMI and FMI. Moroccan children showed higher SBP with high BMI and FMI. WHtR was positively associated with SBP and DBP, similar in all ethnic groups. Generally, strongest associations with blood pressure were found for BMI in all ethnic groups. CONCLUSION: Ethnic-specific associations between BMI, and FMI and blood pressure are present at young age, with Turkish children showing the highest increase in blood pressure with increasing body size. The higher blood pressure in the Black-Caribbean and Moroccan children with low BMI needs further research. WHtR or FMI do not seem to be associated more strongly to blood pressure than BMI in any ethnic group.

Socioeconomic inequalities in lipid and glucose metabolism in early childhood in a population-based cohort: the ABCD-Study.

BACKGROUND: Socioeconomic inequalities in cardiovascular disease are pervasive, yet much remains to be understood about how they originate. The objective of this study was to explore the relations of socioeconomic status to lipid and glucose metabolism as indicators of cardiovascular health in 5-6 year olds. Additionally to explore the explanatory role of maternal factors, birth outcome, and child factors. METHODS: In 1308 5-6 year old ethnic Dutch children from the ABCD cohort study, lipids (cholesterol, LDL, HDL, triglycerides), glucose and C-peptide were measured after an overnight-fast. RESULTS: There were no differences in cholesterol, HDL, LDL, and triglycerides between socioeconomic groups, as indicated by maternal education and income adequacy. However, children of low educated mothers had on average a higher glucose (ß = 0.15; 95% confidence interval (CI) 0.03 - 0.27), logC-peptide (ß = 0.07; 95% CI 0.04 - 0.09), and calculated insulin resistance (HOMA-IR) (ß = 0.15; 95% CI 0.08 - 0.22) compared to children of high educated mothers. Only childhood BMI partly explained these differences (models controlled for age, height, and sex). CONCLUSIONS: The socioeconomic gradient in cardiovascular risk factors seems to emerge in early childhood. In absence of underlying mechanisms these empirical findings are relevant for public health care and further explanatory research.

Educational inequalities in perinatal outcomes: the mediating effect of smoking and environmental tobacco exposure.

OBJECTIVE: Socioeconomic status (SES) is adversely associated with perinatal outcomes. This association is likely to be mediated by tobacco exposure. However, previous studies were limited to single perinatal outcomes and devoted no attention to environmental tobacco exposure. Therefore, this study aimed firstly to explain the role of maternal smoking in the association between maternal education and preterm birth (PTB), low birth weight (LBW) and small for gestational age (SGA), and secondly to explain whether environmental tobacco smoke mediates these associations further. STUDY DESIGN: This study was nested in a population-based cohort study in the Netherlands, the Amsterdam Born Children and their Development (ABCD) study. Analyses were done in a sample of 3821 pregnant women of Dutch origin, using logistic regression analysis. RESULTS: Least educated women, who were more often smoking and exposed to environmental tobacco smoke, had a significantly higher risk of PTB (OR 1.95 [95% CI: 1.19-3.20]), LBW (OR 2.41 [95% CI: 1.36-4.27]) and SGA (OR 1.90 [95% CI 1.32-2.74]) than highly educated women. The mediating effect of smoking in the least educated women was 43% for PTB, 55% for LBW and 66% for SGA. Environmental tobacco smoke did not explain these associations further. After adjustment for maternal smoking, the association between lower maternal education and pregnancy outcomes was no longer significant. CONCLUSIONS: Smoking explains to a considerable extent the association between lower maternal education and adverse perinatal outcomes. Therefore, tobacco-interventions in lower educated women should be primarily focussed on maternal smoking to reduce PTB, LBW, and SGA. Additional attention to environmental tobacco exposure does not seem to reduce educational inequalities in perinatal outcomes.

Ethnic differences in weight retention after pregnancy: the ABCD study.

BACKGROUND: Postpartum weight retention contributes to the development of overweight and obesity in women of childbearing age and is more pronounced in ethnic minority groups. This study examined ethnic differences in postpartum weight retention and the explanatory role of socio-economic status (SES), mental health and lifestyle. METHODS: In the Amsterdam Born Children and their Development (ABCD) study, a large multi-ethnic cohort study conducted in The Netherlands, women filled out questionnaires in the first trimester of pregnancy and 3-5 months postpartum. A total of 4213 women provided data on weight gain, ethnicity, SES, mental health and lifestyle during and after pregnancy. Postpartum weight retention was defined as a difference of ≥5 kg between self-reported pre-pregnancy and postpartum weight. The influence of ethnicity on postpartum weight retention was assessed in logistic regression analyses. Whether the role of ethnicity was attenuated by adding SES, mental health and lifestyle factors were subsequently investigated. RESULTS: Marked differences in weight change during and after pregnancy were found between ethnic groups. Turkish women had significantly more weight retention than Dutch women. This difference could not be explained by other factors. CONCLUSION: In the prevention of postpartum weight retention, no single approach seems applicable to all ethnic groups. During pregnancy, health professionals should focus on Turkish women in particular, as they appear to have the highest risk of weight retention.

Validation of self-reported folic acid use in a multiethnic population: results of the Amsterdam Born Children and their Development study.

OBJECTIVE: To assess folic acid supplementation rates and validate the self-reporting of folic acid supplement use among pregnant women in a multiethnic cohort. DESIGN: Secondary analysis of a prospective cohort study. SETTING: Self-reported folic acid supplement use in the Amsterdam Born Children and their Development study cohort was compared with serum folate concentrations using non-parametric trend analysis and linear and logistic regression. SUBJECTS: A total of 4234 pregnant women of various ethnic backgrounds. RESULTS: Serum folate levels showed a significant positive linear trend as reported use of folic acid increased (P < 0·001), which was supported by linear regression (r = 0·49). Odds of having low serum folate concentration decreased with reported early start of folic acid intake. Young, multiparous or non-Western women reported less pre-conception folic acid intake. Non-Western women showed lower serum folate concentrations. The overall rate of over-reporting, i.e. serum folate concentrations ≤20 nmol/l while reporting the use of folic acid supplements, was 20·7 %. Women of Surinamese and Moroccan ancestry had higher odds of over-reporting (OR = 2·3; 95 % CI 1·5, 3·5 and OR = 2·3; 95 % CI 1·3, 4·0, respectively). The odds for Surinamese women remained significant after adjusting for the onset of supplement use, parity and age (OR = 1·7; 95 % CI 1·1, 2·6). CONCLUSIONS: Although self-reporting is a valid method for assessing folic acid supplement use in a multiethnic population, some participants do over-report. Surinamese and possibly Moroccan women appear to over-report more often. Rates of supplementation are low, especially in non-Western women. This suggests the need for intensifying current campaigns or perhaps even additional advice to start or continue to use folic acid post-conceptionally.