Measuring early childhood health and health disparities: a new approach

Latent class analysis of the association between polycyclic aromatic hydrocarbon exposures and body mass index

BACKGROUND

People experience multiple co-occurring exposures to environmental pollutants, but analyses of multiple exposures have rarely been reported.

OBJECTIVES

We used latent class analysis to estimate co-exposures to multiple polycyclic aromatic hydrocarbons (PAH), and tested the associations of latent classes to body mass index.

METHODS

We analyzed National Health and Nutrition Examination Survey (NHANES) 2013-2014 data. The sample included 2354 people aged 6-80 years. Measures included seven urinary PAH metabolites, BMI, and demographic and behavioral covariates. People were classified into mutually exclusive latent classes characterized by unique profiles of multiple PAH exposures. These classes were used as categorical independent variables in weighted multiple regression models with BMI as the dependent measure. Models were analyzed overall and by age groups (6-19, 20-59, and 60 and over.) We compared results using latent classes to results using a summed PAH exposure measure.

RESULTS

Five latent classes were identified. Two of these classes were significantly associated with higher BMI overall (p < .0001) and for the two youngest age groups. One of these classes was characterized by high multiple exposures across all PAHs, and one by moderate exposures but relatively high naphthalene and phenanthrene. The summed PAH score was associated with higher BMI only for the youngest age group.

CONCLUSIONS

Persons experience multiple co-exposures to PAHs that are related to BMI and obesity across age groups. Latent class analysis provides information on higher order interactions among multiple chemicals that a summed score does not. Future work may apply this approach to other outcomes or types of co-exposures.

Pockets of progress amidst persistent racial disparities in low birthweight rates

Racial disparities persist in adverse perinatal outcomes such as preterm birth, low birthweight (LBW), and infant mortality across the U.S. Although pervasive, these disparities are not universal. Some communities have experienced significant improvements in black (or African American) birth outcomes, both in absolute rates and in rate ratios relative to whites. This study assessed county-level progress on trends in black and white LBW rates as an indicator of progress toward more equal birth outcomes for black infants. County-level LBW data were obtained from the 2003 to 2013 U.S. Natality files. Black LBW rates, black-white rate ratios and percent differences over time were calculated. Trend lines were first assessed for significant differences in slope (i.e., converging, diverging, or parallel trend lines). For counties with parallel trend lines, intercepts were tested for statistically significant differences (sustained equality vs. persistent disparities). To assess progress, black LBW rates were compared to white LBW rates, and the trend lines were tested for significant decline. Each county's progress toward black-white equality was ultimately categorized into five possible trend patterns (n = 408): (1) converging LBW rates with reductions in the black LBW rate (decreasing disparities, n = 4, 1%); (2) converging LBW rates due to worsening white LBW rates (n = 5, 1%); (3) diverging LBW rates (increasing disparities, n = 9, 2%); (4) parallel LBW rates (persistent disparities, n = 373, 91%); and (5) overlapping trend lines (sustained equality, n = 18, 4%). Only four counties demonstrated improvement toward equality with decreasing black LBW rates. There is significant county-level variation in progress toward racial equality in adverse birth outcomes such as low birthweight. Still, some communities are demonstrating that more equitable outcomes are possible. Further research is needed in these positive exemplar communities to identify what works in accelerating progress toward more equal birth outcomes.

Establishing a protocol for building a pan-Canadian population-based monitoring system for early childhood development for children with health disorders: Canadian Children's Health in Context Study (CCHICS)

INTRODUCTION

Health disorders early in life have tremendous impact on children's developmental trajectories. Almost 80% of children with health disorders lack the developmental skills to take full advantage of school-based education relative to 27% of children without a health disorder. In Canada, there is currently a dearth of nationally representative data on the social determinants of early childhood development for children with health disorders. Evidence from Canada and other countries indicate that poorer developmental outcomes in typically developing children are associated with lower socioeconomic status (SES). However, to date, it is not known whether this relationship is stronger among children with health disorders. The study's objectives are to estimate the prevalence and to investigate social determinants of developmental outcomes for young children with health disorders, using the Early Development Instrument (EDI).

METHODS AND ANALYSIS

Study objectives will be achieved through three steps. First, using existing EDI data for 10 provinces and 2 territories collected from 2004 to 2015, we will investigate differences in developmental health outcomes among children with identified health disorders. Second, population-level EDI data will be linked with neighbourhood sociodemographic census data to explore associations between socioeconomic characteristics and rates of specific diagnoses among children aged 5-6 years, including trends over time. Third, for 3 of these 12 regions, additional health and/or education databases will be linked at an individual level. These data will be used to establish differences in EDI outcomes in relation to the age-of-onset of diagnosis, and presence of intervention or treatment.

ETHICS AND DISSEMINATION

Study methodologies have been approved by the Hamilton Integrated Research Ethics Board. The results of the analyses of developmental health outcomes for children with health disorders combined with SES will have implications for both health service delivery and school-based intervention strategies. Results will contribute to a framework for public policy.

Estimating benefit equity of government health subsidy in healthcare Services in Shandong Province, China: a cross-sectional study

Background

Government health subsidy (GHS) is an effective tool to improve population health in China. Ensuring an equitable allocation of GHS, particularly among the poorer socio-economic groups, is a major goal of China’s healthcare reform.

The paper aims to explore how GHS was allocated across different socioeconomic groups, and how well the overall health system was performing in terms of the allocation of subsidy for different types of health services.

Methods

Data from China’s National Health Services Survey (NHSS) in 2013 were used. Benefit incidence analysis (BIA) was applied to examine if GHS was equally distributed across income quintile. Benefit incidence was presented as each quintile’s percentage share of total benefits, and the concentration index (CI) and Kakwani index (KI) were calculated. Health benefits from three types of healthcare services (primary health care, outpatient and inpatient services) were analyzed, separated into urban and rural populations. In addition, the distribution of benefits was compared to the distribution of healthcare need (measured by self-reported illness and chronic disease) across income quintiles.

Results

In urban populations, the CI value of GHS for primary care was negative. (− 0.14), implying an allocation tendency toward poor region; the CI values of outpatient and inpatient services were both positive (0.174 and 0.194), indicating allocation tendencies toward rich region. Similar allocation pattern was observed in rural population, with pro-poor tendency of primary care service (CI = − 0.082), and pro-rich tendencies of outpatient (CI = 0.153) and inpatient services (CI = 0.203). All the KI values of three health services in urban and rural populations were negative (− 0.4991,-0.1851 and − 0.1651; − 0.482, − 0.247and − 0.197), indicating that government health subsidy was progressive and contributed to the narrowing of economic gap between the poor and rich.

Conclusions

The inequitable distribution of GHS in China exited in different healthcare services; however, the GHS benefit is generally progressive. Future healthcare reforms in China should not only focus on expanding the coverage, but also on improving the equity of distribution of healthcare benefits.

Latent class analysis to model multiple chemical exposures among children

BACKGROUND

Children are exposed to multiple potentially harmful chemicals simultaneously. Efforts to understand the patterns and consequences of these exposures have been hampered by statistical limitations in estimations of higher order interactions.

OBJECTIVES

The current study uses latent class analysis, a form of person-centered modeling to identify unobservable subgroups within populations and examine relationships between latent classes and measures of immune function.

METHODS

Data from the National Health and Nutrition Examination Survey 2011-2012 were analyzed. A sample of 721 children aged 6-19 years were included who provided data on 47 chemicals of interest representing six chemical classes. Groups were identified using latent class analysis controlling for race/ethnicity, age, sex and poverty status.

RESULTS

Two alternative approaches to identifying latent classes each resulted in similar three class solutions, including one group of children characterized by low co-exposures across chemicals, a group with moderate co-exposure levels, and a group characterized by high co-occurring levels of polycyclic aromatic hydrocarbons, volatile organic compounds, phenols and phthalates. Under one of the approaches, latent classes were significantly associated with immune function as measured by lymphocyte and neutrophil counts.

CONCLUSIONS

Latent class analysis offers a potential approach to measuring and understanding interactions among multiple co-occurring chemical stressors. However, additional work is needed to test the ability of latent classes to predict health variables.

Co-occurrence and clustering of health conditions at age 11: cross-sectional findings from the Millennium Cohort Study

OBJECTIVES

To identify patterns of co-occurrence and clustering of 6 common adverse health conditions in 11-year-old children and explore differences by sociodemographic factors.

DESIGN

Nationally representative prospective cohort study.

SETTING

Children born in the UK between 2000 and 2002.

PARTICIPANTS

11 399 11-year-old singleton children for whom data on all 6 health conditions and sociodemographic information were available (complete cases).

MAIN OUTCOME MEASURES

Prevalence, co-occurrence and clustering of 6 common health conditions: wheeze; eczema; long-standing illness (excluding wheeze and eczema); injury; socioemotional difficulties (measured using Strengths and Difficulties Questionnaire) and unfavourable weight (thin/overweight/obese vs normal).

RESULTS

42.4% of children had 2 or more adverse health conditions (co-occurrence). Co-occurrence was more common in boys and children from lower income households. Latent class analysis identified 6 classes: 'normative' (57.4%): 'atopic burdened' (14.0%); 'socioemotional burdened' (11.0%); 'unfavourable weight/injury' (7.7%); 'eczema/injury' (6.0%) and 'eczema/unfavourable weight' (3.9%). As with co-occurrence, class membership differed by sociodemographic factors: boys, children of mothers with lower educational attainment and children from lower income households were more likely to be in the 'socioemotional burdened' class. Children of mothers with higher educational attainment were more likely to be in the 'normative' and 'eczema/unfavourable weight' classes.

CONCLUSIONS

Co-occurrence of adverse health conditions at age 11 is common and is associated with adverse socioeconomic circumstances. Holistic, child focused care, particularly in boys and those in lower income groups, may help to prevent and reduce co-occurrence in later childhood and adolescence.

Co-Occurrence of Health Conditions during Childhood: Longitudinal Findings from the UK Millennium Cohort Study (MCS)

AIMS

To identify patterns of stability and change in co-occurrence in children between 5-11 years, and to assess if they vary by socio-demographic factors.

METHODS

Data from 9548 singleton children from the UK Millennium Cohort Study (MCS) were assessed for co-occurrence of five common adverse conditions: wheeze; longstanding illness; unfavorable weight; injury; and socio-emotional difficulties. We summed adverse conditions (0-5) for each child at ages 5, 7, and 11 and identified co-occurrence (≥2 conditions). Using multinomial regression, we explored associations between co-occurrence trajectories and child's sex and ethnicity, maternal education, and income quintile.

RESULTS

45.6% of children experienced co-occurrence between 5-11 years (7% experienced constant co-occurrence). More children moved into co-occurrence than moved out (16.9 vs. 11.9%). Mutually-adjusted relative risk ratios (aRRR) showed a gradient by maternal education: compared to children with no co-occurrence whose mothers had a higher/degree, children whose mothers had no qualifications were more likely to move into (aRRR = 1.32(95%CI:1.02,1.70)), out of (1.74(1.34,2.26)), have fluctuating (1.52(1.09,2.10)) or constant co-occurrence (2.58(1.76,3.80)). The same gradient (high vs. low) was evident for income quintiles. Girls were less likely to experience co-occurrence.

CONCLUSIONS

Co-occurrence of adverse conditions is common during childhood, and trajectories are socially patterned. Child-focused care for lower-income children and boys early in life may prevent and reduce co-occurrence in later childhood.

Assessing equity in benefit distribution of government health subsidy in 2012 across East China: benefit incidence analysis

Background

Improving the equitable benefit distribution of government health subsidies, particularly among the country’s poorer socioeconomic groups, is a major goal of China’s healthcare sector reform.

Methods

Benefit incidence analysis was employed to measure the distribution of government health subsidies by income quintile. The concentration index (CI) of different levels of health care facility in urban and rural areas was calculated. A household survey complete through multistage stratified sampling was conducted in 2013 in urban areas (16,908 respondents) and rural areas (19,525 respondents).

Results

The overall CI for urban patients was 0.1068 for outpatient care and 0.1237 for inpatient care. For outpatient care, the CI was 0.0795, 0.0465 and 0.3456, respectively, at primary, secondary and tertiary health care facilities; for inpatient care, the CI was −0.2179, 0.0752 and 0.2883 at the corresponding facility levels. The overall CI for rural outpatients was −0.0659 and 0.0036 for inpatients. For outpatient care, the CI was −0.0818, 0.0567 and 0.0271 at primary, secondary and tertiary facilities, respectively; for inpatient care, the CI was −0.0050, 0.0084 and 0.0252 at the corresponding facility levels.

Conclusions

China’s primary level health care facilities were found to have a more equitable benefit distribution of government health subsidies than the secondary- and tertiary- level facilities. Increased government budget allocations and insurance imbursement rates, and the provision of technical support and qualified medical staff to lower-level hospitals were key factors. However, the provision of equal subsidies to all socioeconomic levels was found to be a potential threat to the equity of government health subsidy distribution.

Health and development among Mexican, black and white preschool children: An integrative approach using latent class analysis

BACKGROUND

Building on an emerging scientific consensus that the concept of child health should encompass chronic conditions, functional abilities, and developmental domains, we delineate the multidimensional health statuses of Mexican, non-Hispanic black, and non-Hispanic white preschool children in the United States. This integrative approach provides the foundation for an in-depth analysis of health disparities.

OBJECTIVE

The research objectives are: (1) to demonstrate a new methodological approach to identifying the major child health statuses; (2) to document differences in the prevalence of those health statuses among children in the largest ethnoracial groups in the U.S.; and (3) to assess whether key sources of disadvantage account for ethnoracial disparities in children's health.

METHODS

With data from a nationally representative sample, we use latent class analysis to estimate a set of latent health statuses that capture the nature of health at age four. The latent class membership of children is predicted using multinomial logistic regression.

RESULTS

Mexican and non-Hispanic black children are more likely than non-Hispanic white children to fall into health statuses distinguished by low cognitive achievement and multiple developmental problems. Mexican children are the most likely to be classified into these problematic health statuses. This pattern persists in multivariate models that incorporate potential explanatory factors, including health at birth, socio-demographic characteristics, home environment, well-child care and center-based child care.

CONCLUSIONS

Latent class analysis is a useful method for incorporating measures of physical conditions, functional problems, and development into a single analysis in order to identify key dimensions of childhood health and locate ethnoracial health disparities.