Composition and decomposition in US gender-specific self-reported health disparities, 1984-2007

Emerging health disparities among college graduates: Understanding the health consequences of education-occupation mismatch

This study examines the health consequences and underlying pathways of education-occupation mismatch. Using a longitudinal sample of college graduates from the Panel Studies of Income Dynamics (1984-2019) and employing longitudinal hybrid models, we found that contemporary vertical mismatch (between education level and educational requirements of occupation) was associated with poorer psychological well-being and bio-behaviors (obesity and smoking), but not physical health. In contrast, horizontal mismatch (between field of study and field required for occupation) did not show clear health consequences. Sequence analysis was employed to uncover the mismatch trajectories and revealed that persistent vertical mismatch over one's career had a greater impact on psychological distress and smoking than episodic mismatch experiences. Furthermore, the linkage between vertical mismatch and health outcomes was likely shaped by psychosocial processes rather than reduced material well-being. These findings imply that education-occupation vertical (mis)match produces health disparities between occupationally matched and mismatched college graduates.

Subjective health in adolescence: Comparing the reliability of contemporaneous, retrospective, and proxy reports of overall health

Self-rated health (SRH) is one of the most important social science measures of health. Yet its measurement properties remain poorly understood. Most studies ignore the measurement error in SRH despite the bias resulting from even random measurement error. Our goal is to estimate the measurement reliability of SRH in contemporaneous, retrospective, and proxy indicators. We use the National Longitudinal Study of Adolescent to Adult Health to estimate the reliability of SRH relative to proxy assessments and respondents' recollections of past health. Even the best indicators - contemporaneous self-reports - have a modest reliability of ~0.6; retrospective and proxy assessments fare much worse, with reliability less than 0.2. Moreover, not correcting for measurement error in SRH leads to a ~20-40% reduction in its correlation with other measures of health. Researchers should be skeptical of analyses that treat these subjective reports as explanatory variables and fail to take account of their substantial measurement error.

Unobserved Population Heterogeneity and Dynamics of Health Disparities

BACKGROUND

A growing body of literature has reported widening educational health disparities across birth cohorts or time periods in the United States, but has paid little attention to the implication of mortality selection on the cohort trend in health disparities.

OBJECTIVE

This study investigates how changes in the variance of unobserved frailty over time may complicate the interpretation of cohort trends in health disparities and life expectancy.

METHODS

We use the microsimulation method to test the effect of mortality selection and further propose a counterfactual simulation procedure to estimate its contribution. Data used in the simulations are based on Panel Studies of Income Dynamics 1968-2013, National Health and Nutrition Examination Survey data 1999-2012, and National Health Interview Survey data 1986-2011.

RESULTS

Simulation shows that mortality selection may generate seemingly contradictory trends in health disparities and life expectancy across birth cohorts at the group and individual level. Life expectancy can change even when individual mortality curve is fixed. In the absence of a change in the causal effect of education on mortality at the individual level, an educational life expectancy gap can change across cohorts as a result of the change in frailty variance. Empirical analysis shows that mortality selection accounts for a sizeable amount of contribution to the widening educational life expectancy gap from the 1950s to 1960s birth cohorts in the United States.

CONTRIBUTION

We demonstrate mortality selection can complicate the cohort trend in health disparities and life expectancy and propose a counterfactual simulation method to evaluate its contribution.

Univariate predictors of maternal concentrations of environmental chemicals: The MIREC study

BACKGROUND

The developing fetus and pregnant woman can be exposed to a variety of environmental chemicals that may adversely affect their health. Moreover, environmental exposure and risk disparities are associated with different social determinants, including socioeconomic status (SES) and demographic indicators. Our aim was to investigate whether and how maternal concentrations of a large panel of persistent and non-persistent environmental chemicals vary according to sociodemographic and lifestyle characteristics in a large pregnancy and birth cohort.

METHODS

Data were analyzed from the Maternal-Infant Research on Environmental Chemicals (MIREC) Study, a cohort of pregnant women (N=2001) recruited over four years (2008-2011) in 10 cities across Canada. In all, 1890 urine and 1938 blood samples from the first trimester (1st and 3rd trimester for metals) were analysed and six sociodemographic and lifestyle indicators were assessed: maternal age, household income, parity, smoking status, country of birth and pre-pregnancy body mass index (BMI).

RESULTS

We found these indicators to be significantly associated with many of the chemicals measured in maternal blood and urine. Women born outside Canada had significantly higher concentrations of di-2-ethylhexyl and diethyl phthalate metabolites, higher levels of all metals except cadmium (Cd), as well as higher levels of polychlorinated biphenyls (PCBs) and legacy organochlorine pesticides (OCPs). Nulliparity was associated with higher concentrations of dialkyl phosphates (DAPs), arsenic, dimethylarsinic acid (DMAA), perfluoroalkyl substances (PFASs) and many of the persistent organic pollutants. Smokers had higher levels of bisphenol A, Cd and perfluorohexane sulfonate, while those women who had never smoked had higher levels of triclosan, DMAA, manganese and some OCPs.

CONCLUSION

Our results demonstrated that inequitable distribution of exposure to chemicals among populations within a country can occur. Sociodemographic and lifestyle factors are an important component of a thorough risk assessment as they can impact the degree of exposure and may modify the individual's susceptibility to potential health effects due to differences in lifestyle, cultural diets, and aging.

Factors of change and cumulative factors in self-rated health trajectories: a systematic review

In Western societies, self-rated health (SRH) inequalities have increased over the past decades. Longitudinal studies suggest that the SRH trajectories of disadvantaged populations are declining at a faster rate than those of advantaged populations, resulting in an accumulation of (dis)advantages over the life course, as postulated by the Cumulative Advantage/Disadvantage (CAD) model. The objectives of this study are to conduct a systematic review of the factors influencing SRH trajectories in the adult population and to assess to what extent the findings support the CAD model. Based on the inclusion criteria, 36 articles, using 15 nationally representative databases, were reviewed. The results show that young age, high socioeconomic position and marital transitions (entering a partnership) are advantageous factors of change in SRH trajectories. However, evidence for cumulative influences supporting the CAD model remains limited: gender, ethnicity, education and employment status are only moderately associated with growing influences over time, and the cumulative influences of income, occupation, age and marital status are weak. In conclusion, this systematic review provides consolidated evidence on the factors influencing SRH trajectories, though the inclusion of only 15 nationally representative databases may limit the generalization of the results.

Associations between socioeconomic status and environmental toxicant concentrations in adults in the USA: NHANES 2001-2010

Low level chronic exposure to toxicants is associated with a range of adverse health effects. Understanding the various factors that influence the chemical burden of an individual is of critical importance to public health strategies. We investigated the relationships between socioeconomic status (SES) and bio-monitored chemical concentration in five cross-sectional waves of the U.S. National Health and Nutrition Examination Survey (NHANES). We utilised adjusted linear regression models to investigate the association between 179 toxicants and the poverty income ratio (PIR) for five NHANES waves. We then selected a subset of chemicals associated with PIR in 3 or more NHANES waves and investigated potential mediating factors using structural equation modelling. PIR was associated with 18 chemicals in 3 or more NHANES waves. Higher SES individuals had higher burdens of serum and urinary mercury, arsenic, caesium, thallium, perfluorooctanoic acid, perfluorononanoic acid, mono(carboxyoctyl) phthalate and benzophenone-3. Inverse associations were noted between PIR and serum and urinary lead and cadmium, antimony, bisphenol A and three phthalates (mono-benzyl, mono-isobutyl, mono-n-butyl). Key mediators included fish and shellfish consumption for the PIR, mercury, arsenic, thallium and perfluorononanoic acid associations. Sunscreen use was an important mediator in the benzophenone-3/PIR relationship. The association between PIR and cadmium or lead was partially mediated by smoking, occupation and diet. These results provide a comprehensive analysis of exposure patterns as a function of socioeconomic status in US adults, providing important information to guide future public health remediation measures to decrease toxicant and disease burdens within society.

Rising U.S. income inequality and the changing gradient of socioeconomic status on physical functioning and activity limitations, 1984-2007

This study examines the interactive contextual effect of income inequality on health. Specifically, we hypothesize that income inequality will moderate the relationships between individual-level risk factors and health. Using National Health Interview Survey data 1984-2007 (n = 607,959) and U.S. Census data, this paper estimates the effect of the dramatic increase in income inequality in the U.S. over the past two decades on the gradient of socioeconomic status on two measures of health (i.e., physical functioning and activity limitations). Results indicate that increasing income inequality strengthens the protective effects of family income, employment, college education, and marriage on these two measures of health. In contrast, high school education's protective effect (relative to less than a high school education) weakens in the context of increasing income inequality. In addition, we find that increasing income inequality exacerbates men's disadvantages in physical functioning and activity limitations. These findings shed light on research about growing health disparities in the U.S. in the last several decades.