Maternal education, lone parenthood, material hardship, maternal smoking, and longstanding respiratory problems in childhood: testing a hierarchical conceptual framework

The influence of disparities on intensive care outcomes in children with respiratory diseases: A systematic review

CONTEXT

The negative effects of socioeconomic, environmental and ethnic inequalities on childhood respiratory diseases are known in the development of persistent asthma and can result in adverse outcomes. However, little is known about the effects of these disparities on pediatric intensive care unit (PICU) outcomes in respiratory diseases.

OBJECTIVE

The purpose of this systematic review is to evaluate the literature on disparities in socioeconomic, environmental and ethnic determinants and PICU outcomes. We hypothesize that these disparities negatively influence the outcomes of children's respiratory diseases at the PICU.

METHODS

A literature search (in PubMed, Embase.com and Web of Science Core Collection) was performed up to September 30, 2022. Two authors extracted the data and independently evaluated the risk of bias with appropriate assessment methods. Articles were included if the patients were below 18 years of age (excluding neonatal intensive care unit admissions), they concerned respiratory diseases and incorporated socioeconomic, ethnic or environmental disparities.

RESULTS

Eight thousand seven hundred fourty-six references were reviewed, and 15 articles were included; seven articles on the effect of socioeconomic status, five articles on ethnicity, one on the effect of sex and lastly two on environmental factors. All articles but one showed an unfavorable outcome at the PICU.

CONCLUSION

Disparities in socioeconomic (such as a low-income household, public health insurance), ethnic and environmental factors (such as exposure to tobacco smoke and diet) have been assessed as risk factors for the severity of children's respiratory diseases and can negatively influence the outcomes of these children admitted and treated at the PICU.

Pollen exposure is associated with risk of respiratory symptoms during the first year of life

BACKGROUND

Pollen exposure is associated with respiratory symptoms in children and adults. However, the association of pollen exposure with respiratory symptoms during infancy, a particularly vulnerable period, remains unclear. We examined whether pollen exposure is associated with respiratory symptoms in infants and whether maternal atopy, infant's sex or air pollution modifies this association.

METHODS

We investigated 14,874 observations from 401 healthy infants of a prospective birth cohort. The association between pollen exposure and respiratory symptoms, assessed in weekly telephone interviews, was evaluated using generalized additive mixed models (GAMMs). Effect modification by maternal atopy, infant's sex, and air pollution (NO₂ , PM_2.5 ) was assessed with interaction terms.

RESULTS

Per infant, 37 ± 2 (mean ± SD) respiratory symptom scores were assessed during the analysis period (January through September). Pollen exposure was associated with increased respiratory symptoms during the daytime (RR [95% CI] per 10% pollen/m³ : combined 1.006 [1.002, 1.009]; tree 1.005 [1.002, 1.008]; grass 1.009 [1.000, 1.23]) and nighttime (combined 1.003 [0.999, 1.007]; tree 1.003 [0.999, 1.007]; grass 1.014 [1.004, 1.024]). While there was no effect modification by maternal atopy and infant's sex, a complex crossover interaction between combined pollen and PM_2.5 was found (p-value 0.003).

CONCLUSION

Even as early as during the first year of life, pollen exposure was associated with an increased risk of respiratory symptoms, independent of maternal atopy and infant's sex. Because infancy is a particularly vulnerable period for lung development, the identified adverse effect of pollen exposure may be relevant for the evolvement of chronic childhood asthma.

Associations between respiratory and vascular function in early childhood

BACKGROUND AND OBJECTIVE

The link between respiratory and vascular health is well documented in adult populations. Impaired lung function is consistently associated with thicker arteries and higher incidence of cardiovascular disease. However, there are limited data on this relationship in young children and the studies that exist have focussed on populations at high risk of cardiorespiratory morbidity. We determined if an association exists between respiratory and cardiovascular function in young children and, if so, whether it is confounded by known cardiorespiratory risk factors.

METHODS

Respiratory and vascular data from a prospective cohort study established to evaluate the health implications 3 years after coal mine fire smoke exposure in children aged 3-5 years were used. Respiratory function was measured using the forced oscillation technique and included resistance at 5 Hz (R₅ ), reactance at 5 Hz (X₅ ) and area under the reactance curve (AX). Vascular health was measured by carotid intima-media thickness (ultrasound) and pulse wave velocity (arterial tonometry). Regression analyses were used to examine the relationship between the respiratory Z-scores and cardiovascular measures. Subsequent analyses were adjusted for potential confounding by maternal smoking during pregnancy, maternal education and exposure to fine particulate matter <2.5 μm in aerodynamic diameter (PM_2.5 ).

RESULTS

Peripheral lung function (X₅ and AX), but not respiratory system resistance (R₅ ), was associated with vascular function. Adjustment for maternal smoking, maternal education and early life exposure to PM_2.5 had minimal effect on these associations.

CONCLUSION

These observations suggest that peripheral lung stiffness is associated with vascular stiffness and that this relationship is established early in life.

Health Inequalities in Children and Adolescents: A Scoping Review of the Mediating and Moderating Effects of Family Characteristics

This scoping review systematically mapped evidence of the mediating and moderating effects of family characteristics on health inequalities in school-aged children and adolescents (6-18 years) in countries with developed economies in Europe and North America. We conducted a systematic scoping review following the PRISMA extension for Scoping Reviews recommendations. We searched the PubMed, PsycINFO and Scopus databases. Two reviewers independently screened titles, abstracts and full texts. Evidence was synthesized narratively. Of the 12,403 records initially identified, 50 articles were included in the synthesis. The included studies were conducted in the United States (n = 27), Europe (n = 18), Canada (n = 3), or in multiple countries combined (n = 2). We found that mental health was the most frequently assessed health outcome. The included studies reported that different family characteristics mediated or moderated health inequalities. Parental mental health, parenting practices, and parent-child-relationships were most frequently examined, and were found to be important mediating or moderating factors. In addition, family conflict and distress were relevant family characteristics. Future research should integrate additional health outcomes besides mental health, and attempt to integrate the complexity of families. The family characteristics identified in this review represent potential starting points for reducing health inequalities in childhood and adolescence.

A spatial analysis of the association between social vulnerability and the cumulative number of confirmed deaths from COVID-19 in United States counties through November 14, 2020

Objective

Coronavirus disease 2019 (COVID-19) is classified as a natural hazard, and social vulnerability describes the susceptibility of social groups to potential damages from natural hazards. Therefore, the objective of this study was to examine the association between social vulnerability and the cumulative number of confirmed COVID-19 deaths (per 100,000) in 3,141 United States counties.

Methods

The cumulative number of COVID-19 deaths was obtained from USA Facts. Variables related to social vulnerability were obtained from the Centers for Disease Control and Prevention Social Vulnerability Index and the 2018 5-Year American Community Survey. Data were analyzed using spatial autoregression models.

Results

Lowest income and educational level, as well as high proportions of single parent households, mobile home residents, and people without health insurance were positively associated with a high cumulative number of COVID-19 deaths.

Conclusion

In conclusion, there are regional differences in the cumulative number of COVID-19 deaths in United States counties, which are affected by various social vulnerabilities. Hence, these findings underscore the need to take social vulnerability into account when planning interventions to reduce COVID-19 deaths.

Parental educational level and childhood wheezing and asthma: A prospective cohort study from the Japan Environment and Children's Study

BACKGROUND

The influence of mothers' and fathers' educational levels in separate evaluations of asthma has not been fully investigated. This study aims to examine the associations of the mother's and fathers' educational levels with childhood wheeze and asthma adjusting for crude and pre-and post-natal modifiable risk factors.

METHODS

We conducted a prospective cohort study using data from the Japan Environment and Children's Study, which recruited pregnant women from 2011 to 2014. The mother's and father's educational levels were surveyed by a questionnaire during the pregnancy, and childhood wheezing and doctor-diagnosed asthma were estimated using a 3-year questionnaire. Multilevel logistic regression analysis was performed to evaluate the association between the mother's and father's educational levels and childhood wheezing and asthma, adjusted for pre-and post-natal factors.

RESULTS

A total of 69,607 pairs of parents and their single infants were analyzed. We found 17.3% of children had wheezing and 7.7% had asthma. In crude analyses, lower educational level of parents was associated with an increased risk of childhood wheezing and asthma. After full adjustment, a lower educational level of mothers was associated with an increased risk of childhood asthma (junior high school (reference: high school); odds ratio (OR): 1.17, 95% CI, 1.01-1.36), and higher educational level, especially the mother's, was associated with an increased risk of childhood wheezing (technical junior college, technical/vocational college, or associate degree (ECD3); OR: 1.12, 95% CI, 1.06-1.18, bachelor's degree, or postgraduate degree; OR: 1.10, 95% CI, 1.03-1.18), and asthma (ECD3; OR: 1.13, 95% CI, 1.04-1.21).

CONCLUSIONS

Parents' lower educational level was a crude risk factor for childhood wheezing and asthma. However, an increased risk of wheezing due to mothers' higher educational level was found after adjusting for pre-and post-natal factors.

Health gradients in emergency visits and hospitalisations for paediatric respiratory diseases: A population-based retrospective cohort study

BACKGROUND

Socio-economically deprived children face a disproportionate burden of respiratory diseases. The association between area-level material and social deprivation and emergency department (ED) visits and hospitalisations for paediatric respiratory diseases has not been explored.

OBJECTIVES

We evaluated health inequalities in emergency department (ED) visits and hospitalisations for paediatric respiratory diseases according to material and social deprivation indexes.

METHODS

This population-based retrospective cohort study deterministically linked birth, ED visits and hospitalisation data, and census-based, area-level deprivation indexes for all singleton children born in the province of Alberta, Canada, between 2005 and 2010 who had at least one recorded ED visit or hospitalisation for respiratory diseases in their first five years of life. We classified ED visits and hospitalisations for seven respiratory diseases by deprivation indexes. Concentration indexes (CInd) and area-level concentration curves measured health gradients across deprivation groups. Rate ratios (RR) evaluated associations between deprivation indexes and respiratory episodes of care.

RESULTS

The study cohort included 198 572 newborns. The highest CInd were found in ED visits for other acute lower respiratory tract infections (oLRTI; CInd -0.22, 95% confidence interval [CI] -0.32, -0.12) and bronchiolitis (CInd -0.21, 95% CI -0.29, -0.12), and for pneumonia hospitalisations (CInd -0.23, 95% CI -0.33, -0.13). Croup ED visits had a low inequality degree. Compared to social deprivation, the material deprivation index presented a more consistent health gradient of increased episodes of care with increasing deprivation. oLRTI ED visits (RR 2.60, 95% CI 2.34, 2.92) and pneumonia hospitalisations (RR 2.57, 95% CI 2.31, 2.86) presented the largest inequalities between the least and most materially deprived groups.

CONCLUSIONS

We found a concentration of ED visits and hospitalisations for paediatric respiratory diseases in the most deprived groups. However, health inequalities are present across the material and social deprivation spectrum. Compared to the social deprivation index, the material index presented clearer paediatric respiratory health gradients.

Pathways to inequalities in child health

From birth, children living in disadvantaged socioeconomic circumstances (SECs) suffer from worse health than their more advantaged peers. The pathways through which SECs influence children's health are complex and inter-related, but in general are driven by differences in the distribution of power and resources that determine the economic, material and psychosocial conditions in which children grow up. A better understanding of why children from more disadvantaged backgrounds have worse health and how interventions work, for whom and in what contexts, will help to reduce these unfair differences. Macro-level change is also required, including the reduction of child poverty through improved social security systems and employment opportunities, and continued investment in high-quality and accessible services (eg, childcare, key workers, children's centres and healthy school environments). Child health professionals can play a crucial role by being mindful of the social determinants of health in their daily practice, and through advocating for more equitable and child-focussed resource allocation.

Mother's education and offspring asthma risk in 10 European cohort studies

Highly prevalent and typically beginning in childhood, asthma is a burdensome disease, yet the risk factors for this condition are not clarified. To enhance understanding, this study assessed the cohort-specific and pooled risk of maternal education on asthma in children aged 3-8 across 10 European countries. Data on 47,099 children were obtained from prospective birth cohort studies across 10 European countries. We calculated cohort-specific prevalence difference in asthma outcomes using the relative index of inequality (RII) and slope index of inequality (SII). Results from all countries were pooled using random-effects meta-analysis procedures to obtain mean RII and SII scores at the European level. Final models were adjusted for child sex, smoking during pregnancy, parity, mother's age and ethnicity. The higher the score the greater the magnitude of relative (RII, reference 1) and absolute (SII, reference 0) inequity. The pooled RII estimate for asthma risk across all cohorts was 1.46 (95% CI 1.26, 1.71) and the pooled SII estimate was 1.90 (95% CI 0.26, 3.54). Of the countries examined, France, the United Kingdom and the Netherlands had the highest prevalence's of childhood asthma and the largest inequity in asthma risk. Smaller inverse associations were noted for all other countries except Italy, which presented contradictory scores, but with small effect sizes. Tests for heterogeneity yielded significant results for SII scores. Overall, offspring of mothers with a low level of education had an increased relative and absolute risk of asthma compared to offspring of high-educated mothers.

Maternal History of Childhood Abuse and Risk of Asthma and Allergy in 2-Year-Old Children

OBJECTIVES

Exposure to child abuse (CA) is associated with an increased risk of developing asthma and allergies; it is unknown if that risk is present across generations. This study investigated if 2-year-old children born to mothers with a history of CA were at an increased risk of receiving a diagnosis of asthma or allergies.

METHODS

Data from 1,551 participants were collected as part of the All Our Babies (AOB) study, a prospective pregnancy cohort. During pregnancy, each woman provided information about her own history of CA, and at 24 months postpartum, she provided information about her child's medical diagnoses. Symptoms of maternal depression and anxiety were assessed during pregnancy and at 24 months postpartum.

RESULTS

Unadjusted models showed that compared to children born to mothers without a history of CA, 2-year-old children born to mothers with a history of CA were more likely to have had a diagnosis of asthma (7.4% vs 4.2%, p = .016) or allergy (15.6% vs 9.2%, p < .001). Maternal symptoms of depression assessed in late pregnancy and symptoms of depression and anxiety at 24 months postpartum were significant mediators of the relationship between maternal CA and 2-year-old asthma diagnosis. Maternal symptoms of depression and anxiety assessed in late pregnancy were also significant mediators of the relationship between maternal CA and 2-year-old allergy diagnosis.

CONCLUSIONS

The results indicate that maternal exposure to CA is associated with increased risk of asthma and allergy in their 2-year-old children; symptoms of maternal depression and anxiety were identified as pathways linking the variables.

Maternal Education and Investments in Children's Health

Maternal education differences in children's academic skills have been strongly linked to parental investment behaviors. This study extended this line of research to investigate whether these same maternal education patterns in parenting are observed among a set of parenting behaviors that are linked to young children's health. Drawing on data from the Early Childhood Longitudinal Study, Birth Cohort (n = 5,000) and longitudinal models incorporating random effects, the authors found that higher levels of maternal education were associated with more advantageous health investment behaviors at each phase of early development (9 months, 2 years, 4 years, 5 years). Moreover, these disparities were typically largest at the developmental stage when it was potentially most sensitive for children's long-term health and development. These findings provide further evidence of a developmental gradient associated with mothers' education and new insight into the salience of mothers' education for the short- and long-term health and well-being of their children.

Inflammatory markers predict episodes of wheezing during the first year of life in Bangladesh

BACKGROUND

Environmental factors that influence wheezing in early childhood in the developing world are not well understood and may be useful in predicting respiratory outcomes. Therefore, our objective was to determine the factors that can predict wheezing.

METHODS

Children from Dhaka, Bangladesh were recruited at birth and episodes of wheezing were measured alongside nutritional, immunological and socioeconomic factors over a one-year period. Poisson Regression with variable selection was utilized to determine what factors were associated with wheezing.

RESULTS

Elevated serum IL-10 (rate ratio (RR) = 1.51, 95% confidence interval (CI): 1.22-1.87), IL-1β (RR = 1.55, 95% CI: 1.26-1.93) C-reactive protein (CRP) (RR = 1.41, 95% CI: 1.03-1.93) in early life, and male gender (RR = 1.52, 95% CI: 1.27-1.82) predicted increased wheezing episodes. Conversely, increased fecal alpha-1-antitrypsin (RR = 0.87, 95% CI: 0.76-1.00) and family income (RR = 0.98, 95% CI: 0.97-0.99) were associated with a decreased number of episodes of wheezing.

CONCLUSIONS

Systemic inflammation early in life, poverty, and male sex placed infants at risk of more episodes of wheezing during their first year of life. These results support the hypothesis that there is a link between inflammation in infancy and the development of respiratory illness later in life and provide specific biomarkers that can predict wheezing in a low-income country.

Paternal Age, Paternal Presence and Children's Health: An Observational Study

In an observational study of 31,257 children we investigated the effects of paternal age at the time of the child's birth, paternal absence and non-biological fathers on children's health. Results are per 5 year change in paternal age. Older fathers were associated with lower rates of unintentional injuries, odds ratio (OR)=0.966, P=0.0027. There was a quadratic association between paternal age and risk of hospital admission, β=0.0121, P=0.0109, with minimum risk at paternal age 37.7. Absent fathers were associated with increased risk of hospital admission, OR=1.19, P<10(-3), lower rates of complete immunizations to 9 months, OR=0.562, P<10(-3), higher Strength and Difficulties Questionnaire (SDQ) difficulties scores: β=0.304, P=0.0024 (3 year olds), β=0.697, P<10(-3) (5 year olds). Non-biological fathers were associated with increased risk of unintentional injury, OR=1.16, P=0.0319 and hospital admission, OR=1.26, P=0.0166; lower rates of complete immunizations to 9 months, OR=0.343, P=0.0309 and higher SDQ difficulties scores: β=0.908, P<10(-3).

Family hardships and serum cotinine in children with asthma

BACKGROUND AND OBJECTIVE

A better understanding of how poverty-related hardships affect child health could highlight remediable intervention targets. Tobacco smoke exposure may be 1 such consequence of family hardship. Our objective was to explore the relationship between family hardships and tobacco exposure, as measured by serum cotinine, a tobacco metabolite, among children hospitalized for asthma.

METHODS

We prospectively enrolled a cohort of 774 children, aged 1 to 16 years, admitted for asthma or bronchodilator-responsive wheezing. The primary outcome was detectable serum cotinine. We assessed family hardships, including 11 financial and social variables, through a survey of the child's caregiver. We used logistic regression to evaluate associations between family hardship and detectable cotinine.

RESULTS

We had complete study data for 675 children; 57% were African American, and 74% were enrolled in Medicaid. In total, 56% of children had detectable cotinine. More than 80% of families reported ≥ 1 hardship, and 41% reported ≥ 4 hardships. Greater numbers of hardships were associated with greater odds of having detectable cotinine. Compared with children in families with no hardships, those in families with ≥ 4 hardships had 3.7-fold (95% confidence interval, 2.0-7.0) greater odds of having detectable serum cotinine in adjusted analyses. Lower parental income and educational attainment were also independently associated with detectable serum cotinine.

CONCLUSIONS

Family hardships are prevalent and associated with detectable serum cotinine level among children with asthma. Family hardships and tobacco smoke exposure may be possible targets for interventions to reduce health disparities.

Parental socioeconomic status, childhood asthma and medication use--a population-based study

Background

Little is known about how parental socioeconomic status affects offspring asthma risk in the general population, or its relation to healthcare and medication use among diagnosed children.

Methods

This register-based cohort study included 211,520 children born between April 2006 and December 2008 followed until December 2010. Asthma diagnoses were retrieved from the National Patient Register, and dispensed asthma medications from the Prescribed Drug Register. Parental socioeconomic status (income and education) were retrieved from Statistics Sweden. The associations between parental socioeconomic status and outcomes were estimated by Cox proportional hazard regression.

Results

Compared to the highest parental income level, children exposed to all other levels had increased risk of asthma during their first year of life (e.g. hazard ratio, HR 1.19, 95% confidence interval, CI 1.09–1.31 for diagnosis and HR 1.17, 95% CI 1.08–1.26 for medications for the lowest quintile) and the risk was decreased after the first year, especially among children from the lowest parental income quintile (HR 0.84, 95% CI 0.77–0.92 for diagnosis, and HR 0.80, 95% CI 0.74–0.86 for medications). Further, compared to children with college-educated parents, those whose parents had lower education had increased risk of childhood asthma regardless of age. Children with the lowest parental education had increased risk of an inpatient (HR 2.07, 95% CI 1.61–2.65) and outpatient (HR 1.32, 95% CI 1.18–1.47) asthma diagnosis. Among diagnosed children, those from families with lower education used fewer controller medications than those whose parents were college graduates.

Conclusions

Our findings indicate an age-varying association between parental income and childhood asthma and consistent inverse association regardless of age between parental education and asthma incidence, dispensed controller medications and inpatient care which should be further investigated and remedied.

Complete home smoking bans and antitobacco contingencies: a natural experiment

INTRODUCTION

The California antitobacco culture may have influenced home smoking bans in Mexico. Based on the Behavioral Ecological Model, exposure to socially reinforcing contingencies or criticism may explain adoption of home smoking bans in Tijuana, Mexico, approximating rates relative to San Diego, California, and higher than those in Guadalajara, Mexico.

METHODS

A representative cross-sectional population survey of Latinos (N = 1,901) was conducted in San Diego, Tijuana, and Guadalajara between June 2003 and September 2004. Cities were selected to represent high-, medium-, and low-level exposure to antitobacco social contingencies of reinforcement in a quasiexperimental analysis of possible cultural influences across borders.

RESULTS

Complete home smoking ban prevalence was 91% in San Diego, 66% in Tijuana, and 38% in Guadalajara (p < .001). Sample cluster-adjusted logistic regression showed significantly lower odds of complete home smoking bans in Guadalajara (odds ratio [OR] = .048) and in Tijuana (OR = .138) compared to San Diego after control for demographics. Odds of complete home smoking bans in both Guadalajara and Tijuana in comparison with San Diego were weakened when mediators for bans were controlled in predictive models. Direction of association was consistent with theory. When theoretical mediators were explored as possible moderators, weak and nonsignificant associations were obtained for all interaction terms. Bootstrap analyses demonstrated that our multivariable logistic regression results were reliable.

CONCLUSIONS

Results suggest that California antismoking social contingencies mediate complete home smoking bans in all 3 cities and may account for the greater effects in Tijuana contrasted with Guadalajara.

Socioeconomic and sociodemographic factors associated with asthma related outcomes in early childhood: the Generation R Study

Rationale

Few studies have analyzed the association of socioeconomic and sociodemographic factors with asthma related outcomes in early childhood, including Fraction of exhaled Nitric Oxide (FeNO) and airway resistance (Rint). We examined the association of socioeconomic and sociodemographic factors with wheezing, asthma, FeNO and Rint at age 6 years. Additionally, the role of potential mediating factors was studied.

Methods

The study included 6717 children participating in The Generation R Study, a prospective population-based cohort study. Data on socioeconomic and sociodemographic factors, wheezing and asthma were obtained by questionnaires. FeNO and Rint were measured at the research center. Statistical analyses were performed using logistic and linear regression models.

Results

At age 6 years, 9% (456/5084) of the children had wheezing symptoms and 7% (328/4953) had asthma. Children from parents with financial difficulties had an increased risk of wheezing (adjusted Odds Ratio (aOR) = 1.63, 95% Confidence Interval (CI):1.18–2.24). Parental low education, paternal unemployment and child's male sex were associated with asthma, independent of other socioeconomic or sociodemographic factors (aOR = 1.63, 95% CI:1.24–2.15, aOR = 1.85, 95% CI:1.11–3.09, aOR = 1.58, 95% CI:1.24–2.01, respectively). No socioeconomic or gender differences in FeNO were found. The risks of wheezing, asthma, FeNO and Rint measurements differed between ethnic groups (p<0.05). Associations between paternal unemployment, child's sex, ethnicity and asthma related outcomes remained largely unexplained.

Conclusions

This study showed differences between the socioeconomic and sociodemographic correlates of wheezing and asthma compared to the correlates of FeNO and Rint at age 6 years. Several socioeconomic and sociodemographic factors were independently associated with wheezing and asthma. Child's ethnicity was the only factor independently associated with FeNO. We encourage further studies on underlying pathways and public health intervention programs, focusing on reducing socioeconomic or sociodemographic inequalities in asthma.

Low income/socio-economic status in early childhood and physical health in later childhood/adolescence: a systematic review

To systematically review the literature on the relationship between early childhood low income/socioeconomic status (SES) and physical health in later childhood/adolescence, to identify gaps in the literature and to suggest new avenues for research. A systematic search of electronic databases from their start date to November 2011 was conducted to identify prospective longitudinal studies in industrialized countries with a measure of low income/SES in the first 5 years of life and physical health outcomes in later childhood or adolescence. STROBE criteria were used to assess study quality. Risk estimates were expressed as odds ratios with 95 % confidence intervals where possible. Heterogeneity of studies precluded meta-analysis. Nine studies fulfilled the inclusion criteria. Significant associations of early childhood low income/SES with activity-limiting illness, parent-reported poor health status, acute and recurrent infections, increasing BMI percentile and hospitalization were reported. Results for parent-reported asthma were less consistent: there was a significant association with low income/SES in early childhood in 2 studies but null findings in 3 others. This systematic review of the association of early childhood low income/SES with physical health status in later childhood and adolescence shows that, in contrast to the extensive literature on the impact of poor childhood social circumstances on adult health, the evidence base is limited. The literature points to some associations of early low income/SES with later poor health status, but many key research questions remain unanswered. Implications for further research are considered.

Factors that mediate racial/ethnic disparities in US fetal death rates

OBJECTIVES

We sought to determine the importance of socioeconomic factors, maternal comorbid conditions, antepartum and intrapartum complications of pregnancy, and fetal factors in mediating racial disparities in fetal deaths. METHODS. We undertook a mediation analysis on a retrospective cohort study of hospital-based deliveries with a gestational age between 23 and 44 weeks in California, Missouri, and Pennsylvania from 1993 to 2005 (n = 7,104,674).

RESULTS

Among non-Hispanic Black women and Hispanic women, the fetal death rate was higher than among non-Hispanic White women (5.9 and 3.6 per 1000 deliveries, respectively, vs 2.6 per 1000 deliveries; P < .01). For Black women, fetal factors mediated the largest percentage (49.6%; 95% confidence interval [CI] = 42.7, 54.7) of the disparity in fetal deaths, whereas antepartum and intrapartum factors mediated some of the difference in fetal deaths for both Black and Asian women. Among Hispanic women, socioeconomic factors mediated 35.8% of the disparity in fetal deaths (95% CI = 25.8%, 46.2%).

CONCLUSIONS

The factors that mediate racial/ethnic disparities in fetal death differ depending on the racial/ethnic group. Interventions targeting mediating factors specific to racial/ethnic groups, such as improved access to care, may help reduce US fetal death disparities.

Increased health risks of children with single mothers: the impact of socio-economic and environmental factors

BACKGROUND

Adverse effects of single parenthood on children's health have been reported before. Socio-economic difficulties are discussed as mediating factors. As child health also depends on environmental conditions, we investigated the impact of environmental exposures and socio-economic factors on differences in health outcomes of children with single mothers vs. couple families.

METHODS

Data on 17,218 pre-school children (47% female) from three cross-sectional surveys conducted during 2004-07 in Germany were analysed. Health and exposure assessment were primarily based on parental report. Effects of socio-economic indicators (maternal education, household income) and environmental factors (traffic load at the place of residence, perceived environmental quality) on associations of four health outcomes (parent-reported health status, asthma, overweight, psychological problems) with single parenthood were determined by logistic regression analyses.

RESULTS

Children with single mothers showed an increased risk regarding parent-reported poor health status [boys: odds ratio (OR) 1.39 (95% confidence interval (CI): 1.06-1.82), girls: 1.73 (1.28-2.33)], psychological problems [boys: 1.90 (1.38-2.61), girls: 1.58 (1.03-2.42)], overweight [only boys: OR 1.23 (1.01-1.50) and asthma [only girls: OR 1.90 (1.15-3.15)]. Adjusting for socio-economic factors attenuated the strength of the association of family type with child health. Although environmental factors were associated with most health outcomes investigated and children of single mothers were more often exposed, these environmental factors did not alter the differences between children with single mothers and couple families.

CONCLUSIONS

The increased health risks of children from single-mother families vs. couple families are partly explained by socio-economic factors, but not by the environmental exposures studied.

Children of low socioeconomic status show accelerated linear growth in early childhood; results from the Generation R Study

OBJECTIVES

People of low socioeconomic status are shorter than those of high socioeconomic status. The first two years of life being critical for height development, we hypothesized that a low socioeconomic status is associated with a slower linear growth in early childhood. We studied maternal educational level (high, mid-high, mid-low, and low) as a measure of socioeconomic status and its association with repeatedly measured height in children aged 0-2 years, and also examined to what extent known determinants of postnatal growth contribute to this association.

METHODS

This study was based on data from 2972 mothers with a Dutch ethnicity, and their children participating in The Generation R Study, a population-based cohort study in Rotterdam, The Netherlands (participation rate 61%). All children were born between April 2002 and January 2006. Height was measured at 2 months (mid-90% range 1.0-3.9), 6 months (mid-90% range 5.6-11.4), 14 months (mid-90% range 13.7-17.9) and 25 months of age (mid-90% range 23.6-29.6).

RESULTS

At 2 months, children in the lowest educational subgroup were shorter than those in the highest (difference: -0.87 cm; 95% CI: -1.16, -0.58). Between 1 and 18 months, they grew faster than their counterparts. By 14 months, children in the lowest educational subgroup were taller than those in the highest (difference at 14 months: 0.40 cm; 95% CI: 0.08,0.72). Adjustment for other determinants of postnatal growth did not explain the taller height. On the contrary, the differences became even larger (difference at 14 months: 0.61 cm; 95% CI: 0.26,0.95; and at 25 months: 1.00 cm; 95% CI: 0.57,1.43)

CONCLUSIONS

Compared with children of high socioeconomic status, those of low socioeconomic status show an accelerated linear growth until the 18th month of life, leading to an overcompensation of their initial height deficit. The long-term consequences of these findings remain unclear and require further study.

Tracking exposure to child poverty during the first 10 years of life in a Quebec birth cohort

OBJECTIVES

Early childhood poverty is associated with adult chronic diseases. The objectives of this study were to examine patterns of exposure to poverty during the first 10 years of life in the Quebec Longitudinal Study of Child Development (QLSCD) cohort according to three measures of poverty and to explore family characteristics associated with different poverty exposures.

METHOD

Data from 1,334 participants from the QLSCD were collected annually at home from ages 5 months through 10 years. Household income (previous 12 months) and sources of income were recorded at each data round. Poverty status was operationalized as 1) living below the low income cut-off of Statistics Canada, 2) receiving social welfare and 3) being in the lowest quintile of socio-economic status. We plotted trends in the prevalence of child poverty over time. We used latent class growth modelling to identify subgroups with similar poverty trajectories. Duration of poverty according to each measure was computed separately for early childhood, middle childhood, and the entire 10 years of life.

RESULTS

Four trajectories of poverty were identified: stable poor, decreasing likelihood, increasing likelihood, and never poor. The three measures of poverty do not cover the same population, yet the characteristics of those identified as poor are similar. Children of non-European, immigrant mothers were most likely to be poor, and there was a higher likelihood of children from single-parent families to live in chronic poverty during the first 10 years.

CONCLUSION

A large proportion of children are exposed to poverty before 10 years of age. More effective public policies could reduce child poverty.

Prevalence and correlates of asthma among children in central St. Petersburg, Russia: cross-sectional study

AIM

To estimate the prevalence of asthma among children in central St. Petersburg and to evaluate associations between asthma and socio-demographic, biological, and environmental factors.

METHODS

A cross-sectional study included 1464 children aged 0-18 years from two central districts of St. Petersburg. Parents filled out a questionnaire on children's respiratory health, characteristics at birth, socio-demographic data, housing situation, and their own history of asthma and allergies. The diagnosis of asthma was based on the results of spirometry in children aged > or =5 years and on questionnaire data as reported by parents of younger children. Independent effects of the investigated factors on asthma were assessed by multiple logistic regression analysis. Crude and adjusted odds ratios (OR) with 95% confidence intervals (CI) were calculated.

RESULTS

The estimated prevalence of asthma was 7.4% (95% CI, 6.2-8.8). A history of allergies (OR, 1.6; 95% CI, 1.0-2.6), bronchitis, bronchiolitis, or pneumonia in infancy (OR, 12.2; 95% CI, 7.3-20.5), and self-reported parental allergies (OR, 3.6; 95% CI, 2.2-5.8 for one parent and OR, 7.1; 95% CI, 3.0-17.0 for both parents) were associated with childhood asthma. Children whose mothers were out of work also had higher prevalence of asthma than the reference group (OR, 3.4; 95% CI, 1.1-10.4).

CONCLUSION

The prevalence of asthma is several times higher than what is officially reported for St. Petersburg's inner city children population. Early life events and socio-demographic and biologic factors were associated with asthma in children.

Parents' use and views of the national standard Personal Child Health Record: a survey in two primary care trusts

BACKGROUND

The Personal Child Health Record (PCHR) is a booklet given to parents in the UK, following the birth of a child, to be used as the main record of their growth, development and uptake of preventative health services. The national standard PCHR has been available since April 2004. The aim of this survey was to explore parental views of the 'new' PCHR, their experiences in receiving it, and its subsequent use, focusing on specific issues of current debate among health professionals.

METHODS

A parental questionnaire (n = 89) was administered in July 2004, in 10 child health clinics located in two primary care trusts; one in central London and the other in Buckinghamshire.

RESULTS

Nearly all parents (98%) reported that they used the PCHR as a record of their child's health and development and 92% reported that they 'always' took it with them when seeing healthcare staff about their child. Some parents (22%) indicated that they had not been given a satisfactory explanation as to how to use the PCHR, at the time it was issued to them. Parents reported that health visitors were more likely than other health professionals to use the PCHR both to obtain information about their child and to record information. The majority of respondents (78%) were happy for the level of maternal education to be documented in their child's PCHR.

CONCLUSIONS

Parents used, appreciated and liked the design of the national standard PCHR. Health visitors and primary care staff used the PCHR more than secondary care staff. The potential benefits of the PCHR will only be maximized if other healthcare professionals respond by using it.

Effect of parental smoking on cotinine levels in newborns

BACKGROUND

Smoking is a major risk factor for cot death. Many infants smoke passively as a result of parental smoking. This paper reports on infants exposed to a smoking environment and how they accumulate metabolites of cigarette smoke, such as cotinine, which may be physiologically harmful.

AIM

To assess cotinine levels in infants of smoking parents.

METHOD

Cotinine excretion in urine was assessed in 104 infants, of whom 71 had smoking parents and 33 had non-smoking parents. All cotinine levels were measured at approximately 12 weeks of age. The subjects were selected from a database of infants in developmental physiological studies which assessed the impact of various factors on early postnatal development.

RESULTS

On average babies with at least one parent who was a current cigarette smoker excreted 5.58 (95% CI 3.4 to 9.5) times as much cotinine in the urine as did the babies of non-smoking parents. Maternal smoking was the largest contributing factor. Co-sleeping (p = 0.037) and the minimum room temperature (p = 0.028) were significant contributory factors.

CONCLUSION

Infants from smoking households accumulate cotinine, a metabolite of nicotine, which may have a detrimental effect on the cardiorespiratory system.

Dental caries in 0- to 5-year-old Brazilian children: prevalence, severity, and associated factors

OBJECTIVE

This cross-sectional study investigated the prevalence and severity of dental caries and their association with demographic and socio-economic variables in Brazilian preschoolers.

METHODS

The study population comprised 1487 0- to 5-year-old children attending government nurseries in Canoas, southern Brazil. Questionnaires regarding information related to the independent variables (age, gender, maternal level of education, and family income) were completed by the parents. Clinical examinations were carried out by five trained examiners and results were expressed using the deft index (World Health Organization criteria), including white spots. The outcomes considered in this study were caries occurrence (deft > 0) and caries severity (deft).

RESULTS

Forty per cent of the children (589/1487) presented dental caries [mean deft (SD): 1.53 (2.75)]. Deft increased with age (P < 0.001) and was significantly higher in children from mothers with low educational level (P = 0.001) and low family income (P = 0.001). The greatest increase in caries prevalence and severity occurred between age groups of 1 and 2 years. Logistic regression demonstrated higher odds of dental caries with mother's completing < 4 years education, after adjusting for confounding.

CONCLUSION

These findings indicate the need for preventive programmes, which should begin in the first year of life, with special attention given to families with mothers presenting low education levels.