Prenatal Health, Educational Attainment, and Intergenerational Inequality: The Northern Finland Birth Cohort 1966 Study

Preterm birth and educational disadvantage: Heterogeneous effects

Although preterm birth is the leading cause of perinatal morbidity and mortality in advanced economies, evidence about the consequences of prematurity in later life is limited. Using Swedish registers for cohorts born 1982-94 (N  =  1,087,750), we examine the effects of preterm birth on school grades at age 16 using sibling fixed effects models. We further examine how school grades are affected by degree of prematurity and the compensating roles of family socio-economic resources and characteristics of school districts. Our results show that the negative effects of preterm birth are observed mostly among children born extremely preterm (<28 weeks); children born moderately preterm (32-<37 weeks) suffer no ill effects. We do not find any evidence for a moderating effect of parental socio-economic resources. Children born extremely preterm and in the top decile of school districts achieve as good grades as children born at full term in an average school district.Supplementary material for this article is available at: http://dx.doi.org/10.1080/00324728.2022.2080247.

Evaluating the Role of Parental Education and Adolescent Health Problems in Educational Attainment

This article reconsiders the role of social origin in health selection by examining whether parental education moderates the association between early health and educational attainment and whether health problems mediate the intergenerational transmission of education. We used longitudinal register data on Finns born in 1986–1991 (n = 352,899). We measured the completion of secondary and tertiary education until age 27 and used data on hospital care and medication reimbursements to assess chronic somatic conditions, frequent infections, and mental disorders at ages 10–16. We employed linear probability models to estimate the associations between different types of health problems and educational outcomes and to examine moderation by parental education, both overall in the population and comparing siblings with and without health problems. Finally, we performed a mediation analysis with g-computation to simulate whether a hypothetical eradication of health problems would weaken the association between parental and offspring education. All types of health problems reduced the likelihood of secondary education, but mental disorders were associated with the largest reductions. Among those with secondary education, there was further evidence of selection to tertiary education. High parental education buffered against the negative impact of mental disorders on completing secondary education but exacerbated it in the case of tertiary education. The simulated eradication of health problems slightly reduced disparities by parental education in secondary education (up to 10%) but increased disparities in tertiary education (up to 2%). Adolescent health problems and parental education are strong but chiefly independent predictors of educational attainment.

The cognitive development from childhood to adolescence of low birthweight children born after medically assisted reproduction-a UK longitudinal cohort study

Background

Previous research has documented that children conceived through medically assisted reproduction (MAR) are at increased risk of poor birth outcomes, such as low birthweight (LBW), which are risk factors for stunted longer-term cognitive development. However, parents who undergo MAR to conceive have, on average, advantaged socioeconomic backgrounds which could compensate for the negative effects of being born LBW. Previous studies have not analysed whether the negative effects of LBW are attenuated among MAR conceived children.

Methods

We draw on the UK Millennium Cohort Study (sweeps 1–6) which contains a sub-sample of (N = 396) MAR-conceived children. The dependent variable measures cognitive ability at around ages 3, 5, 7, 11 and 14. We examine the cognitive development of four groups of children: MAR-conceived low birthweight (MAR LBW); MAR-conceived non-low birthweight (MAR NLBW); naturally conceived low birthweight (NC LBW); naturally conceived non-low birthweight (NC NLBW). We estimate the two following linear regression models for each sweep: (i) a baseline model to examine the unadjusted association between cognitive development and low birthweight by mode of conception; and (ii) a model adjusted by socio-demographic family characteristics.

Results

In baseline models, MAR LBW children [age 3: β  =  0.021, 95% confidence interval (CI): -0.198, 0.241; age 5: β  =  0.21, 95% CI: 0.009, 0.418; age 7: β  =  0.163, 95% CI: -0.148, 0.474; age 11: β  =  0.003, 95% CI: -0.318, 0.325; age 14: β  =  0.156, 95% CI: -0.205, 0.517], on average perform similarly in cognitive ability relative to NC NLBW at all ages, and display higher cognitive scores than NC LBW children until age 7. When we account for family characteristics, differences are largely attenuated and become close to zero at age 14.

Conclusions

Despite the higher incidence of LBW among MAR compared with NC children, they do not seem to experience any disadvantage in their cognitive development compared with naturally conceived children. This finding is likely explained by the fact that, on average, MAR children are born to socioeconomically advantaged parents.

Methodological Issues in Population-Based Studies of Multigenerational Associations

Laboratory-based animal research has revealed a number of exposures with multigenerational effects-ones that affect the children and grandchildren of those directly exposed. An important task for epidemiology is to investigate these relationships in human populations. Without the relative control achieved in laboratory settings, however, population-based studies of multigenerational associations have had to use a broader range of study designs. Current strategies to obtain multigenerational data include exploiting birth registries and existing cohort studies, ascertaining exposures within them, and measuring outcomes across multiple generations. In this paper, we describe the methodological challenges inherent to multigenerational studies in human populations. After outlining standard taxonomy to facilitate discussion of study designs and target exposure associations, we highlight the methodological issues, focusing on the interplay between study design, analysis strategy, and the fact that outcomes may be related to family size. In a simulation study, we show that different multigenerational designs lead to estimates of different exposure associations with distinct scientific interpretations. Nevertheless, target associations can be recovered by incorporating (possibly) auxiliary information, and we provide insights into choosing an appropriate target association. Finally, we identify areas requiring further methodological development.

Education is the strongest socio-economic predictor of smoking in pregnancy

AIMS

To investigate socio-economic disparities in smoking in pregnancy (SIP) by the mother's education, occupational class and current economic conditions.

DESIGN

Cross-sectional analysis with linked survey and register data.

SETTING

South-western Finland.

PARTICIPANTS

A total of 2667 pregnant women [70% of the original sample (n = 3808)] from FinnBrain, a prospective pregnancy cohort study.

MEASUREMENTS

The outcome was smoking during the first pregnancy trimester, measured from the Finnish Medical Birth Register. Education and occupational class were linked from population registers. Income support recipiency and subjective economic wellbeing were questionnaire-based measures of current economic conditions. These were adjusted for age, partnership status, residential area type, parental separation, parity, childhood socio-economic background, childhood adversities (the Trauma and Distressing Events During Childhood scale) and antenatal stress (Edinburgh Postnatal Depression Scale). Logistic regressions and attributable fractions (AF) were estimated.

FINDINGS

Mother's education was the strongest socio-economic predictor of SIP. Compared with university education, adjusted odds ratios (aORs) of SIP were: 2.2 [95% confidence interval (CI) = 1.2-3.9; P = 0.011] for tertiary vocational education, 4.4 (95% CI = 2.1-9.0; P < 0.001) for combined general and vocational secondary education, 2.9 (95% CI = 1.4-6.1; P = 0.006) for general secondary education, 9.5 (95% CI 5.0-18.2; P < 0.001) for vocational secondary education and 14.4 (95% CI = 6.3-33.0; P < 0.001) for compulsory schooling. The total AF of education was 0.5. Adjusted for the other variables, occupational class and subjective economic wellbeing did not predict SIP. Income support recipiency was associated positively with SIP (aOR = 1.8; 95% CI = 1.1-3.1; P = 0.022). Antenatal stress predicted SIP (aOR = 2.0; 95% CI = 1.4-2.8; P < 0.001), but did not attenuate its socio-economic disparities.

CONCLUSIONS

In Finland, socio-economic disparities in smoking in pregnancy are attributable primarily to differences in the mother's educational level (low versus high) and orientation (vocational versus general).

Association between birth weight and educational attainment: an individual-based pooled analysis of nine twin cohorts

BACKGROUND

There is evidence that birth weight is positively associated with education, but it remains unclear whether this association is explained by familial environmental factors, genetic factors or the intrauterine environment. We analysed the association between birth weight and educational years within twin pairs, which controls for genetic factors and the environment shared between co-twins.

METHODS

The data were derived from nine twin cohorts in eight countries including 6116 complete twin pairs. The association between birth weight and educational attainment was analysed both between individuals and within pairs using linear regression analyses.

RESULTS

In between-individual analyses, birth weight was not associated with educational years. Within-pairs analyses revealed positive but modest associations for some sex, zygosity and birth year groups. The greatest association was found in dizygotic (DZ) men (0.65 educational years/kg birth weight, p=0.006); smaller effects of 0.3 educational years/kg birth weight were found within monozygotic (MZ) twins of both sexes and opposite-sex DZ twins. The magnitude of the associations differed by birth year in MZ women and opposite-sex DZ twins, showing a positive association in the 1915-1959 birth cohort but no association in the 1960-1984 birth cohort.

CONCLUSION

Although associations are weak and somewhat inconsistent, our results suggest that intrauterine environment may play a role when explaining the association between birth weight and educational attainment.

Profiles of Contextual Risk at Birth and Adolescent Substance Use

This study examined whether there are subgroups of families with distinct profiles of prenatal/birth contextual risk, and whether subgroup membership was differentially related to adolescent substance use. Data from the Northern Finland Birth Cohort 1986 were used. A five-class model provided the most meaningful solution. Large Family Size (7.72%) and Low Risk (69.69%) groups had the lowest levels of alcohol, cigarette, and illegal drug use. Similar high levels for each of the three substance-related outcomes were found for Parent Substance Misuse (11.20%), Maternal School Dropout (4.66%), and Socioeconomic Disadvantage (6.72%) groups. Maternal smoking and drinking while pregnant and paternal heavy alcohol use were found to be key prenatal risk factors that tended to cluster together and co-occur with other prenatal risk factors differently for different subgroups of youth.

Schizotypal and affective traits in the offspring of antenatally depressed mothers - Relationship to family history of psychosis in the Northern Finland 1966 Birth Cohort

BACKGROUND

Maternal depression is relatively common during pregnancy. However, follow-ups of the adult offspring of antenatally depressed mothers are scarce. Previously we found the risk of schizophrenia to be higher in the adult offspring with antenatally depressed mothers and parents with psychosis than in subjects with only one or neither of these risk factors. The aim was to study whether the risk of schizotypal or affective traits differ among adult offspring with antenatally depressed mothers with or without a parental history of psychosis when compared with offspring without antenatally depressed mothers and without parental psychosis.

METHODS

In the general population-based Northern Finland 1966 Birth Cohort (NFBC 1966), the mothers of the cohort members were asked at mid-gestation whether they felt depressed. Parental psychosis (Familial Risk, FR) was detected using the Finnish Care Register for Health Care. In the 31-year field study, seven psychometric questionnaires surveyed schizotypal and affective traits in the offspring. The final sample included 4928 individuals (2203 males).

RESULTS

There were no statistically significant differences in mean scores on the schizotypal and affective scales between offspring with and without antenatally depressed mothers, or between subjects with and without parental psychosis. The scores were not highest in the subjects with both maternal antenatal depressed mood and FR.

CONCLUSION

Surprisingly, maternal depressed mood during pregnancy was unlikely to increase the risk of schizotypy or affective traits in adult offspring, and not even with parental psychosis (FR) in this general population-based birth cohort with about 5000 subjects.

Smoking in pregnancy, adolescent mental health and cognitive performance in young adult offspring: results from a matched sample within a Finnish cohort

BACKGROUND

The association between prenatal exposure to maternal cigarette smoking (PEMCS) and adult cognition is debated, including if there are differences according to sex. We aimed to determine if there are associations between PEMCS and cognition in early adulthood in men and women and examine if observed associations were mediated by adolescent mental health factors that are associated with cognition, namely psychotic-like experiences (PLEs), inattention and hyperactivity, and other externalizing behaviors.

METHODS

Participants were 471 individuals drawn from the general population-based Northern Finland 1986 Birth Cohort (NFBC 1986) followed up from pregnancy and birth to early adulthood; individuals with PEMCS were matched with those without PEMCS by socioeconomic and demographic factors. Cognitive performance in adulthood was assessed with a range of tests and their association with PEMCS was measured by sex using hierarchical linear regression, unadjusted and then controlling for potential confounders, mediators and moderators, including adolescent mental health factors.

RESULTS

There were no associations between PEMCS and cognitive scores in females. In males, there were associations with vocabulary (beta = -0.444, 95% CI: -0.783, -0.104) and matrix reasoning (beta = -0.379, 95% CI: -0.711, -0.047).

CONCLUSIONS

While associations between PEMCS and cognition were limited, observed findings with measures of general intelligence in males contribute to suggestions of differences in response to PEMCS by sex. Furthermore, observed associations may be partly mediated by earlier inattention and hyperactivity. Findings add support to efforts aimed to eliminate smoking in pregnancy.

Effectiveness and cost-effectiveness of the Salut Programme: a universal health promotion intervention for parents and children-protocol of a register-based retrospective observational study

INTRODUCTION

There is inadequate evidence for the effectiveness and cost-effectiveness of health promotion interventions. The Salut Programme aims to reach all parents and children in the Västerbotten County of Sweden with a combination of health promotion interventions initiated during pregnancy and continued over the childhood period. This study protocol describes an effectiveness study and an economic evaluation study, where the ongoing Salut Programme is compared to care-as-usual over the periods of pregnancy, delivery and the child's first 2 years of life.

METHODS

A register-based retrospective observational study design will be used with existing data sources with respect to exposures and outcomes. Outcomes of interest are clustered at 3 points: around the child's birth, 1 month after the child's birth and 2 years after the child's birth. We will simulate an experiment by retrospectively identifying and comparing children and their parents in the geographical areas where the Salut Programme was implemented since 2006 and onwards, and the areas where the Programme was not implemented before 2009. Outcomes will be analysed and compared for the premeasure period, and the postmeasure period for both groups. Our analysis combines difference-in-difference estimation with matching. A complementary analysis will be carried out on the longitudinal subsample of mothers who gave birth at least once during each of the time periods. The economic evaluation aims to capture the wider societal costs and benefits of the Salut Programme for the first 2 years of the children's lives. Incremental costs will be compared with incremental health gains and the results will be presented as a cost-consequence analysis.

ETHICS AND DISSEMINATION

The Regional Ethical Review Board in Umeå has given clearance for the Salut Programme research (2010-63-31M). No individual's identity will be revealed when presenting results. This study will provide information that can guide decision-makers to allocate resources optimally.

Invited Commentary: Multigenerational Social Determinants of Health—Opportunities and Challenges

An emerging area of social epidemiology examines the relationship between grandparental education and grandchild health. In an accompanying article, Huang et al. (Am J Epidemiol. 2015;182(7):568-578) join the small but growing body of research on this topic. It is useful to contextualize Huang et al.'s work within the much larger body of research examining relationships between education and health within a single generation or across 2 generations. These investigators have generally concluded that higher educational attainment is robustly associated with better health. There are many potential mechanisms through which education and other social exposures may affect health outcomes in a single generation or across generations, and estimating direct and indirect effects can be helpful for assessing specific mechanisms. Researchers conducting multigenerational analyses are faced with several challenges, including limited availability of data for some measures (e.g., educational attainment, and sometimes for 1 grandparent only), limited age ranges of participants, disparate social and political contexts in which study participants of different generations have lived, and patterns of social class reproduction. We encourage future researchers to weave together the careful analytical considerations illustrated by Huang et al. with a rich understanding of the social context for each of the generations studied to help overcome these challenges and advance our understanding of multigenerational social determinants of health.

Early childhood WIC participation, cognitive development and academic achievement

For the 22% of American children who live below the federal poverty line, and the additional 23% who live below twice that level, nutritional policy is part of the safety net against hunger and its negative effects on children's development. The Special Supplemental Nutrition Program for Women, Infants and Children (WIC) provides steadily available food from the food groups essential for physical and cognitive development. The effects of WIC on dietary quality among participating women and children are strong and positive. Furthermore, there is a strong influence of nutrition on cognitive development and socioeconomic inequality. Yet, research on the non-health effects of U.S. child nutritional policy is scarce, despite the ultimate goal of health policies directed at children-to enable productive functioning across multiple social institutions over the life course. Using two nationally representative, longitudinal surveys of children-the Early Childhood Longitudinal Study, Birth Cohort (ECLS-B) and the Child Development Supplement (CDS) of the Panel Study of Income Dynamics-I examine how prenatal and early childhood exposure to WIC is associated in the short-term with cognitive development, and in the longer-term with reading and math learning. Results show that early WIC participation is associated with both cognitive and academic benefits. These findings suggest that WIC meaningfully contributes to children's educational prospects.

Childhood and adulthood socio-economic position and hypertensive disorders in pregnancy: the Uppsala Birth Cohort Multigenerational Study

BACKGROUND

Childhood and adulthood socio-economic position (SEP) is associated with cardiovascular disease in later life, but associations with hypertensive disorders in pregnancy are not well established.

OBJECTIVE

The aim of this study was to investigate the association of childhood and adulthood SEP with hypertensive disorders in pregnancy (chronic hypertension, gestational hypertension and pre-eclampsia/eclampsia).

METHOD

Study participants were Swedish women (n=9507) from generation 3 of the Uppsala Birth Cohort Multigenerational Study (UBCoS Multigen) who delivered a live singleton offspring between 1982 and 2008. Social and health data were obtained from routine Swedish registers. Associations of own education (adulthood SEP), and parental education and social class (childhood SEP) with hypertensive disorders were studied using logistic regression with adjustments for age, calendar period, parity, smoking and body mass index.

RESULTS

Low own education was associated with chronic hypertension, but not with gestational hypertension or pre-eclampsia/eclampsia. Increased risk of chronic hypertension was seen in women whose mothers had medium education compared with women whose mothers had high education (OR 2.18, 95% CI 1.03 to 4.62). Women from a manual social class during childhood had twice the risk of chronic hypertension compared with those from non-manual backgrounds (OR 2.19, 95% CI 1.28 to 3.75). Childhood SEP was not associated with gestational hypertension or pre-eclampsia/eclampsia.

CONCLUSIONS

Childhood and adulthood SEP was associated with chronic hypertension in pregnancy. In contrast, no association with childhood or adulthood SEP was seen for gestational hypertension or pre-eclampsia/eclampsia.