Maternal Smoking During Pregnancy and Child Well-Being: A Burning Issue. ESRI Research Bulletin 2012/4/1

It is well established that smoking can damage your health. Nonetheless, around one third of the Irish population continue to smoke. Irish research (Brugha et al., 2009) suggests that most smokers want to give up and half will have tried in the last year but nicotine is a notoriously addictive substance. One measure of its addictiveness can be gleaned from the fact that around 18 per cent of pregnant women smoke at some point during their pregnancy and 13 per cent continue to smoke right through. A positive message to emerge from recent research is that the rate of smoking in pregnancy in Ireland has fallen over time. Data from the Growing Up in Ireland study show that whilst 28 per cent of mothers whose children were born between 1997 and 1998 reported that they smoked during pregnancy, this had fallen to 18 per cent of mothers whose children were born in 2007. This is a decrease of over 35 per cent in the proportion of women smoking during pregnancy. Evidence from the Slán Survey (Brugha et al., 2009) suggests that smoking rates among women under 45 have declined by less than 5 per cent over the same period, suggesting an increasing sensitivity to the dangers of smoking during pregnancy

Investing in Child Health and Development: The Impact of Breastfeeding on Children’s School Performance. ESRI Research Bulletin 2011/2/4

There is now strong evidence that breastfed babies are less prone to stomach upsets, ear infections and the coughs and colds of early childhood than their bottle fed peers. There is also a growing body of evidence that breastfeeding may confer more long term benefits for child development. For example, studies have consistently shown that breastfed children score more highly on cognitive and academic performance tests in later life compared with those who were bottle-fed. At first glance the explanation seems simple: breast milk contains nutrients that improve brain development during infancy leading to longer-term gains in cognitive performance. The story may not be so simple however. Research shows that children who are breastfed are more likely to come from more advantaged households, that is, those with higher levels of education, higher income and social class. This means that these children enjoy other economic and environmental advantages and it may well be that it is these factors, not the breast milk itself, that explains the higher ability scores among the breastfed

Personality and wealth accumulation among older couples: Do dispositional characteristics pay dividends?

This paper explores whether the ‘Big 5’ personality characteristics: Emotional Stability, Extraversion, Conscientiousness, Agreeableness, and Openness to Experience, contribute to net household wealth accumulation among 1172 couple pairs (n = 2344) participating in The Irish Longitudinal Study on Ageing, independent of other socio-demographic and human capital variables. We employ quantile regression to determine whether the effects of personality vary at different levels of the conditional distribution of wealth. Results reveal that the personality characteristics of the financial respondent to the survey are more strongly associated with wealth than those of the non-financial respondent. Specifically, we find that emotional stability and extraversion are positively associated with wealth at the household level among spousal pairs. We also find that conscientiousness is positively associated with wealth, but the relationship is only significant at the lower end of the wealth continuum. In general, agreeableness and openness are negatively associated with wealth although the relationships are non-significant. These findings indicate that personality is an important factor shaping individuals’ consumption preferences and financial decision-making behaviour over the life-course

Maternal smoking during pregnancy and child well-being: a burning issue.

The Growing Up in Ireland study allow us to examine whether smoking conveys an increased risk for behavioral problems when we take account of these social factors. Importantly, the study collected information on the mother’s level of smoking in pregnancy and this provides us with an important additional tool with which to corroborate the causal relationship between exposure to cigarette smoke in the womb and behavioral problems at age 9. If the strength of the relationship between smoking and behavioral problems increases with the level of maternal smoking, this is more persuasive than a simple association. In a paper recently published in the Journal of Abnormal Child Psychology, Cathal McCrory and Richard Layte (McCrory & Layte 2012) did just this. They showed that the risk of the child being reported by his/her teacher as having conduct, attention or hyperactivity problems at age 9 was significantly related to whether the mother smoked during pregnancy and, moreover, that the risk increased with the number of cigarettes smoked during pregnancy

Decomposing the social gradient in children's vocabulary skills at 3 years of age: A mediation analysis using data from a large representative cohort study

Disparities in children's expressive language by socio-economic status are evident early in childhood and impact children's development and educational attainment. This study investigated the processes by which maternal education, as a powerful indicator for socio-economic status, affects early expressive language. A nationally representative cohort study of 8,062 children resident in the Republic of Ireland were assessed on the British Ability Scales (BAS)Naming Vocabulary Test at 36 months. A significant difference of almost six points was found between the mean vocabulary test scores of children whose mothers had completed the minimum level of educational attainment compared with children whose mothers had a degree-level qualification. Mediation analysis revealed that 78% of the difference was explained by mediating variables, with differences in household income, parental practice, and material resources accounting for most of the variation. The findings support interventions which redress gaps in maternal education, income, and caregiving

How does socio-economic position (SEP) get biologically embedded? A comparison of allostatic load and the epigenetic clock(s)

Individuals of lower socio-economic position (SEP) carry a heavier burden of disease and morbidity and live shorter lives on average compared with their more advantaged counterparts. This has sparked research interest in the processes and mechanisms via which social adversity gets biologically embedded. The present study directly compares the empirical worth of two candidate mechanisms: Allostatic Load (AL) and the Epigenetic Clock(s) for advancing our understanding of embodiment using a sub-sample of 490 individuals from the Irish Longitudinal Study (TILDA) who were explicitly selected for this purpose based on their inter-generational life course social class trajectory. A battery of 14 biomarkers representing the activity of 4 different physiological systems: Immunological, Cardiovascular, Metabolic, and Renal was used to construct the AL score. Biomarkers were dichotomised into high and low risk groups according to sex-specific quartiles of risk and summed to create a count ranging from 0-14. Three measures of epigenetic age acceleration were computed according to three sets of age-associated Cytosine-phosphate-Guanine (CpG) sites described by Horvath, Hannum and Levine. AL was strongly socially patterned across a number of measures of SEP, while the epigenetic clocks were not. AL partially mediated the association between measures of SEP and an objective measure of physiological functioning: performance on the Timed Up and Go (TUG test). We conclude that AL may represent the more promising candidate for understanding the pervasive link between SEP and health.Peer reviewe

Socioeconomic position, lifestyle habits and biomarkers of epigenetic aging: a multi-cohort analysis

Differences in health status by socioeconomic position (SEP) tend to be more evident at older ages, suggesting the involvement of a biological mechanism responsive to the accumulation of deleterious exposures across the lifespan. DNA methylation (DNAm) has been proposed as a biomarker of biological aging that conserves memory of endogenous and exogenous stress during life. We examined the association of education level, as an indicator of SEP, and lifestyle-related variables with four biomarkers of age-dependent DNAm dysregulation: the total number of stochastic epigenetic mutations (SEMs) and three epigenetic clocks (Horvath, Hannum and Levine), in 18 cohorts spanning 12 countries. The four biological aging biomarkers were associated with education and different sets of risk factors independently, and the magnitude of the effects differed depending on the biomarker and the predictor. On average, the effect of low education on epigenetic aging was comparable with those of other lifestyle-related risk factors (obesity, alcohol intake), with the exception of smoking, which had a significantly stronger effect. Our study shows that low education is an independent predictor of accelerated biological (epigenetic) aging and that epigenetic clocks appear to be good candidates for disentangling the biological pathways underlying social inequalities in healthy aging and longevity

Comparisons of disease cluster patterns, prevalence and health factors in the USA, Canada, England and Ireland

Abstract Background Identification of those who are most at risk of developing specific patterns of disease across different populations is required for directing public health policy. Here, we contrast prevalence and patterns of cross-national disease incidence, co-occurrence and related risk factors across population samples from the U.S., Canada, England and Ireland. Methods Participants (n = 62,111) were drawn from the US Health and Retirement Study (n = 10,858); the Canadian Longitudinal Study on Ageing (n = 36,647); the English Longitudinal Study of Ageing (n = 7938) and The Irish Longitudinal Study on Ageing (n = 6668). Self-reported lifetime prevalence of 10 medical conditions, predominant clusters of multimorbidity and their specific risk factors were compared across countries using latent class analysis. Results The U.S. had significantly higher prevalence of multimorbid disease patterns and nearly all diseases when compared to the three other countries, even after adjusting for age, sex, BMI, income, employment status, education, alcohol consumption and smoking history. For the U.S. the most at-risk group were younger on average compared to Canada, England and Ireland. Socioeconomic gradients for specific disease combinations were more pronounced for the U.S., Canada and England than they were for Ireland. The rates of obesity trends over the last 50 years align with the prevalence of eight of the 10 diseases examined. While patterns of disease clusters and the risk factors related to each of the disease clusters were similar, the probabilities of the diseases within each cluster differed across countries. Conclusions This information can be used to better understand the complex nature of multimorbidity and identify appropriate prevention and management strategies for treating multimorbidity across countries