The Role of Socioeconomic Status in the Association of Lung Function and Air Pollution-A Pooled Analysis of Three Adult ESCAPE Cohorts.

Ambient air pollution is a leading environmental risk factor and its broad spectrum of adverse health effects includes a decrease in lung function. Socioeconomic status (SES) is known to be associated with both air pollution exposure and respiratory function. This study assesses the role of SES either as confounder or effect modifier of the association between ambient air pollution and lung function.

Socioeconomic position during pregnancy and DNA methylation signatures at three stages across early life: epigenome-wide association studies in the ALSPAC birth cohort.

Background: Socioeconomic experiences are recognized determinants of health, and recent work has shown that social disadvantages in early life may induce sustained biological changes at molecular level that are detectable later in life. However, the dynamics and persistence of biological embedding of socioeconomic position (SEP) remains vastly unexplored.

Methods: Using the data from the ALSPAC birth cohort, we performed epigenome-wide association studies of DNA methylation changes at three life stages (birth, n = 914; childhood at mean age 7.

Socioeconomic position and outdoor nitrogen dioxide (NO) exposure in Western Europe: A multi-city analysis.

Background: Inconsistent associations between socioeconomic position (SEP) and outdoor air pollution have been reported in Europe, but methodological differences prevent any direct between-study comparison.

Objectives: Assess and compare the association between SEP and outdoor nitrogen dioxide (NO) exposure as a marker of traffic exhaust, in 16 cities from eight Western European countries.

Methods: Three SEP indicators, two defined at individual-level (education and occupation) and one at neighborhood-level (unemployment rate) were assessed in three European multicenter cohorts.

Examining if being overweight really confers protection against dementia: Sixty-four year follow-up of participants in the Glasgow University alumni cohort study.

Background: Recent large-scale studies suggest that obesity and overweight may confer protection against future dementia. This observation could, however, be generated by reverse causality. That is, weight loss in the incipient phase of dementia ascribed to diminished self-care, including sub-optimal nutrition, would have the effect of generating such an inverse association.

Relationship between mediation analysis and the structured life course approach.

Many questions in life course epidemiology involve mediation and/or interaction because of the long latency period between exposures and outcomes. In this paper, we explore how mediation analysis (based on counterfactual theory and implemented using conventional regression approaches) links with a structured approach to selecting life course hypotheses. Using theory and simulated data, we show how the alternative life course hypotheses assessed in the structured life course approach correspond to different combinations of mediation and interaction parameters.

Childhood wheezing, asthma, allergy, atopy, and lung function: different socioeconomic patterns for different phenotypes.

Identifying preventable exposures that lead to asthma and associated allergies has proved challenging, partly because of the difficulty in differentiating phenotypes that define homogeneous disease groups. Understanding the socioeconomic patterns of disease phenotypes can help distinguish which exposures are preventable. In the present study, we identified disease phenotypes that are susceptible to socioeconomic variation, and we determined which life-course exposures were associated with these inequalities in a contemporary birth cohort.

Child Allergic Symptoms and Well-Being at School: Findings from ALSPAC, a UK Cohort Study.

Background: Eczema and asthma are common conditions in childhood that can influence children's mental health. Despite this, little is known about how these conditions affect the well-being of children in school. This study examines whether symptoms of eczema or asthma are associated with poorer social and mental well-being in school as reported by children and their teachers at age 8 years.

Child allergic symptoms and mental well-being: the role of maternal anxiety and depression.

Objective: To determine whether maternal mental health mediates the relationship between eczema or asthma symptoms and mental well-being in children.

Study Design: Analysis of 7250 children from the Avon Longitudinal Study of Parents and Children. Child mental well-being at 8 years was measured by the Strengths and Difficulties Questionnaire.

High life in the sky? Mortality by floor of residence in Switzerland.

Living in high-rise buildings could influence the health of residents. Previous studies focused on structural features of high-rise buildings or characteristics of their neighbourhoods, ignoring differences within buildings in socio-economic position or health outcomes. We examined mortality by floor of residence in the Swiss National Cohort, a longitudinal study based on the linkage of December 2000 census with mortality and emigration records 2001-2008.

Loss to follow-up in cohort studies: bias in estimates of socioeconomic inequalities.

Background: Although cohort members tend to be healthy and affluent compared with the whole population, some studies indicate this does not bias certain exposure-outcome associations. It is less clear whether this holds when socioeconomic position (SEP) is the exposure of interest.

Methods: As an illustrative example, we use data from the Avon Longitudinal Study of Parents and Children.

The association between irregular menstruations and acne with asthma and atopy phenotypes.

Earlier menarche and irregular periods, among other markers of sex-hormone levels, have been associated with a higher risk of asthma and allergic diseases. This has suggested an etiologic role of sex hormones in the development of these conditions. The authors investigated the association of age at menarche, irregular periods, duration of menstruation, and acne with reported medical history of asthma and/or atopy (hay fever and/or eczema/urticaria) in a historical cohort of students born before the rise in asthma prevalence in the United Kingdom and attending university in 1948-1968.

A Swiss neighbourhood index of socioeconomic position: development and association with mortality.

Background: Area-based measures of socioeconomic position (SEP) suitable for epidemiological research are lacking in Switzerland. The authors developed the Swiss neighbourhood index of SEP (Swiss-SEP).

Methods: Neighbourhoods of 50 households with overlapping boundaries were defined using Census 2000 and road network data.

Associations between socioeconomic position and asthma: findings from a historical cohort.

Understanding the association between asthma and socioeconomic position (SEP) is key to identify preventable exposures to prevent inequalities and lessen overall disease burden. We aim to assess the variation in asthma across SEP groups in a historical cohort before the rise in asthma prevalence. Male students participating in a health survey at Glasgow University from 1948 to 1968 (n = 11,274) completed medical history of bronchitis, asthma, hay fever, eczema/urticaria, and reported father's occupation.

Measuring socio-economic position for epidemiological studies in low- and middle-income countries: a methods of measurement in epidemiology paper.

Much has been written about the measurement of socio-economic position (SEP) in high-income countries (HIC). Less has been written for an epidemiology, health systems and public health audience about the measurement of SEP in low- and middle-income countries (LMIC). The social stratification processes in many LMIC-and therefore the appropriate measurement tools-differ considerably from those in HIC.

Socioeconomic inequalities in health: individual or area level; does it matter?

In the last decades we have accumulated substantial knowledge about the risk factors that lead to cardiovascular disease. Despite this progress, in this issue of BMC Public Health we learn that little improvement has been made towards reducing inequalities in these risk factors in the UK. Characterizing changes over time can help understanding the mechanisms that underpin health inequalities.

Social inequalities in height: persisting differences today depend upon height of the parents.

Background: Substantial increases in height have occurred concurrently with economic development in most populations during the last century. In high-income countries, environmental exposures that can limit genetic growth potential appear to have lessened, and variation in height by socioeconomic position may have diminished. The objective of this study is to investigate inequalities in height in a cohort of children born in the early 1990s in England, and to evaluate which factors might explain any identified inequalities.

Socioeconomic disparities in trajectories of adiposity across childhood.

Background: Socioeconomic inequalities in obesity are consistently observed in high-income countries. The development of such inequalities across childhood; however, has not been studied using longitudinal data.

Methods: Using data from the Avon Longitudinal Study of Parents and Children (participants were born 1991/2 in South-West England), we modelled trajectories of ponderal index (PI) (N=12 246) from birth to 2 years and body mass index (BMI) (N=11 380) from 2 to 10 years.

Socioeconomic differences in childhood growth trajectories: at what age do height inequalities emerge?

Background: Socioeconomic differentials in adult height are frequently observed, but the age at which these inequalities emerge and the patterns they follow through childhood are unknown.

Subjects And Methods: Using data from the Avon Longitudinal Study of Parents and Children (ALSPAC), height trajectories from birth to 10 years (N=12366) were modelled. Individual trajectories were estimated using mixed-effects models.

Young adulthood body mass index and risk of cancer in later adulthood: historical cohort study.

Objective: To investigate the relationship between body mass index (BMI) in young adulthood and cancer incidence and mortality.

Methods: A total of 9,549 men and 2,657 women had weight and height measured while at university (1948-1968). Participants were traced through the National Health Service Central Register, and cancer registration and death certificates were obtained.

Are there socioeconomic inequalities in cardiovascular risk factors in childhood, and are they mediated by adiposity? Findings from a prospective cohort study.

Background: Socioeconomic gradients in adiposity were not present during childhood for previous generations, but have emerged in contemporary children. It is unknown whether this translates to socioeconomic gradients in associated cardiovascular risk factors in children, with consequent implications for inequalities in coronary heart disease (CHD) and diabetes when these children reach adulthood.

Methods: Using data from 7772 participants aged 10-years from the Avon Longitudinal Study of Parents and Children, we examined the association between maternal education and a large number of cardiovascular risk factors (cholesterol, triglycerides, high-density lipoprotein, apolipoprotein, adiponectin, leptin, C-reactive protein (CRP), interleukin-6 (IL-6) and systolic and diastolic blood pressure), and examined whether inequalities were mediated by adiposity, measured by dual energy X-ray absorptiometry (DXA)-assessed total fat mass.

A common genetic variant in the 15q24 nicotinic acetylcholine receptor gene cluster (CHRNA5-CHRNA3-CHRNB4) is associated with a reduced ability of women to quit smoking in pregnancy.

Maternal smoking during pregnancy is associated with low birth weight and adverse pregnancy outcomes. Women are more likely to quit smoking during pregnancy than at any other time in their lives, but some pregnant women continue to smoke. A recent genome-wide association study demonstrated an association between a common polymorphism (rs1051730) in the nicotinic acetylcholine receptor gene cluster (CHRNA5-CHRNA3-CHRNB4) and both smoking quantity and nicotine dependence.

Is the association between childhood socioeconomic circumstances and cause-specific mortality established? Update of a systematic review.

Objective: To update a systematic review on the association between childhood socioeconomic circumstances and cause-specific mortality. Studies published since 2003 include a far greater number of deaths than was previously available justifying an update of the previous systematic review.

Methods: Individual-level studies examining childhood socioeconomic circumstances and adult overall and cause-specific mortality published between 2003 and April 2007.