Recalibrating the spirit level: An analysis of the interaction of income inequality and poverty and its effect on health

Network Ties, Upward Status Heterophily, and Unanticipated Health Consequences

Using cross-national data containing information on the status rank of network alters, this study investigates the potential negative effects of "upward status heterophily," ties to and perceived interaction with higher status others. According to our main finding, upward status heterophily is associated with poor physical health and lower subjective well-being. We also find that this focal relationship varies across individual and contextual moderators. For subjective well-being only, it is weaker among people who are better educated, have larger nonkin network, and possess greater self-efficacy. Moreover, there is a significant cross-level interaction: For both health outcomes, the relationship is more pronounced in subnational regions that are economically more unequal. Our findings shed light on the mechanisms of the "dark side of social capital" by operationalizing perceived status differential as a proxy for upward social comparison and showing its deleterious consequences in the East Asian context.

Income Inequality and Population Health: Examining the Role of Social Policy

Studies of the relationship between income inequality and life expectancy often speculate about the role of policy, but direct empirical research is limited. Drawing on the neo-materialist perspective, we examine whether the longitudinal association between income inequality and life expectancy is mediated and moderated by policy liberalism in U.S. states (2000-2014). More liberal policy contexts are characterized by greater efforts to regulate the economy, redistribute income, and protect vulnerable groups and lesser efforts to penalize deviant social behavior. We find that state-level income inequality is inversely associated with policy liberalism and life expectancy. The association between income inequality and life expectancy was not mediated by policy liberalism but was moderated by it. The association is attenuated in states with more liberal policy contexts, supporting the neo-materialist perspective. This finding illustrates how states like New York and California (with liberal policy contexts) can exhibit high income inequality and high life expectancy.

A test of the predictive validity of relative versus absolute income for self-reported health and well-being in the United States

BACKGROUND

A classic debate concerns whether absolute or relative income is more salient. Absolute values resources as constant across time and place while relative contextualizes one's hierarchical location in the distribution of a time and place.

OBJECTIVE

This study investigates specifically whether absolute income or relative income matters more for health and well-being.

METHODS

We exploit within-person, within-age, and within-time variation with higher-quality income measures and multiple health and well-being outcomes in the United States. Using the Panel Study of Income Dynamics and the Cross-National Equivalent File, we estimate three-way fixed effects models of self-rated health, poor health, psychological distress, and life satisfaction.

RESULTS

For all four outcomes, relative income has much larger standardized coefficients than absolute income. Robustly, the confidence intervals for relative income do not overlap with zero. By contrast, absolute income mostly has confidence intervals that overlap with zero, and its coefficient is occasionally signed in the wrong direction. A variety of robustness checks support these results.

CONCLUSIONS

Relative income has far greater predictive validity than absolute income for self-reported health and well-being.

CONTRIBUTION

Compared to earlier studies, this study provides a more rigorous comparison and test of the predictive validity of absolute and relative income that is uniquely conducted with data on the United States. This informs debates on income measurement, the sources of health and well-being, and inequalities generally. Plausibly, these results can guide any analysis that includes income in models.

Restless in an Unequal World: Economic Inequality Fuels the Desire for Wealth and Status

Building on theories explaining social outcomes of economic inequality, our research examined the psychological impact of inequality on the desire for wealth and status. Our studies provide both experimental (Studies 1 and 3, Ns = 321 and 596) and correlational (Study 2; N = 141,477 from 73 countries and regions) evidence that higher inequality heightens people’s desire for wealth and status. Notably, this effect of inequality on desire is independent of the influence of societal wealth. Moreover, our results reveal social class differences in why inequality fuels motivations: Lower-class individuals are more likely to respond to higher inequality with a heightened desire reflecting self-improvement concerns, whereas upper-class individuals are more likely to respond with a heightened desire reflecting social comparison concerns. These findings suggest that higher inequality creates an environment of restlessness in which both the poor and the rich feel obliged to seek wealth and status, albeit for different reasons.

Income inequality and COVID-19 mortality: Age-stratified analysis of 22 OECD countries

Our study builds on a growing body of research that demonstrates an association between income inequality and COVID-19 mortality. Using Poisson multivariate regression, we age-stratify our analysis by separately examining each of four age groups over a nine-month study period in 22 OECD countries. Our full regression model controls for national median income and relative poverty, and a set of pandemic-specific variables to capture exposure, susceptibility and treatment. We found that country-level income inequality, as measured by the disposable income Gini coefficient, is significantly and positively associated with COVID-19 mortality for all four age groups. Consistent with previous studies that analyzed all-cause mortality by age, our regression results found that the point estimate of the Gini coefficient generally declines with age. Our results suggest that inequality is possibly acting through generic and pandemic-specific processes to increase mortality via a more pronounced negative COVID-19 socio-economic status gradient in higher inequality countries.

Mattering Mediates Between Fairness and Well-being

Research has suggested a fundamental connection between fairness and well-being at the individual, relational, and societal levels. Mattering is a multidimensional construct consisting of feeling valued by, and adding value to, self and others. Prior studies have attempted to connect mattering to both fairness and a variety of well-being outcomes. Based on these findings, we hypothesize that mattering acts as a mediator between fairness and well-being. This hypothesis was tested through Covariance-Based Structural Equation Modeling (CB-SEM) using multidimensional measures of fairness, mattering, and well-being. Results from a Latent Path Analysis conducted on a representative sample of 1,051U.S. adults provide support to our hypothesis by revealing a strong direct predictive effect of mattering onto well-being and a strong indirect effect of fairness onto well-being through mattering. Results also show that mattering is likely to fully mediate the relationship between fairness and multiple domains of well-being, except in one case, namely, economic well-being. These findings illustrate the value of a focus on mattering to understand the relationship between fairness and well-being and to provide future directions for theory, research, and practice. Theoretical implications for the experience of citizenship and participation, along with cross-cultural considerations, are also discussed.

The health effects of wage setting institutions: How collective bargaining improves health but not because it reduces inequality

Do wage-setting institutions, such as collective bargaining, improve health and, if so, is this because they reduce income inequality? Wage-setting institutions are often assumed to improve health because they increase earnings and reduce inequality and yet, while individual-level studies suggest higher earnings improve well being, the direct effects of these institutions on mortality remains unclear. This paper explores both the relationship between wage-setting institutions and mortality rates whether income inequality mediates this relationship. Using 50 years of data from 22 high-income countries (n ~ 825), I find mortality rates are lower in countries with collective bargaining compared to places with little or no wage protection. While wage-setting institutions may reduce economic inequality, these institutions do not appear to improve health because they reduce inequality. Instead, collective bargaining improves health, in part, because they increase average wage growth. The political and economic drivers of inequality may not, then, be correlated with health outcomes, and, as a result, health scholars need to develop more nuanced theories of the political economy of health that are separate from but in dialogue with the political economy of inequality.

Canalization and Robustness in Human Genetics and Disease

Canalization refers to the evolution of populations such that the number of individuals who deviate from the optimum trait, or experience disease, is minimized. In the presence of rapid cultural, environmental, or genetic change, the reverse process of decanalization may contribute to observed increases in disease prevalence. This review starts by defining relevant concepts, drawing distinctions between the canalization of populations and robustness of individuals. It then considers evidence pertaining to three continuous traits and six domains of disease. In each case, existing genetic evidence for genotype-by-environment interactions is insufficient to support a strong inference of decanalization, but we argue that the advent of genome-wide polygenic risk assessment now makes an empirical evaluation of the role of canalization in preventing disease possible. Finally, the contributions of both rare and common variants to congenital abnormality and adult onset disease are considered in light of a new kerplunk model of genetic effects.

No generalizable effect of income inequality on public support for governmental redistribution among rich democracies 1987-2010

We revisit a longstanding hypothesis that the public become more supportive of redistributive policy as income inequality rises. Previous tests of this hypothesis using various forms of general least squares regressions are inconclusive. We suggest improvements and alternatives to these tests. Using the World Inequality Data and International Social Survey Program we analyze 91 surveys in 18 countries. We incorporate three alternative measures of income inequality, including a measure of liberalization as a known cause of increases in income inequality. We also employ two alternative test formats that arguably reflect the data generating model better than a least squares regression. The first is vector-autoregression aiming to account for path dependency of public opinion and income inequality, and the endogeneity between them. Next is qualitative comparative analysis to capture sets of conditions that collectively should have led to inequality having an impact on public opinion. Finally, we run our regression models separately for low and high socio-economic strata. In all tests we find no measurable impact of income inequality on support for redistribution. From a macro-perspective we argue that this suggests ruling out a general effect that exists across space and time, and focusing instead on theory to explain why there should not be a general effect. Some arguments suggest the public are normatively opposed to what sounds like 'handouts'. We therefore discuss model specification via theory, but also Type II errors, statistical power and the limitations of our conclusions.

Income inequality and firearm homicide in the US: a county-level cohort study

Objective

Income inequality has been rising in the US and thought to be associated with violence especially homicide. About 75% of homicides involve firearms. We quantified the association between county-level income inequality and all-race/ethnicity and race/ethnicity-specific firearm homicide rates among individuals aged 14–39 years.

Methods

We conducted a cohort study of US counties to examine the association of Gini Index (ranging from 0 [perfect income equality] to 1.0 [perfect income inequality]) separately measured in 1990 and 2000 with all-race/ethnicity and race/ethnicity-specific firearm homicide rates in 2005–2015. Generalised linear mixed models with Poisson distribution including a random intercept for state provided IRRs and 95% CIs. Bayesian Poisson-lognormal hierarchical modelling with integrated nested Laplace approximations was used in exploratory spatial analyses. Models accounted for county-level age, sex and race/ethnicity composition, crime rate, deprivation, social capital, urbanicity, and firearm ownership.

Findings

The Gini Index was associated with firearm homicide rates among all races/ethnicities. After accounting for contextual determinants of firearm homicide, the association persisted among African–Americans. In this group, a 1 SD greater Gini Index in 1990 (IRR=1.09; 95% CI 1.02 to 1.16) and 2000 (IRR=1.09; 95% CI 1.01 to 1.17) was associated with greater firearm homicide rates in 2005–2015. Exploratory spatial analyses did not materially change the results.

Conclusion

Policies addressing the gap between the rich and the poor deserve further considerations for reducing firearm homicide rates. Incorporating income inequality to refine measures of socioeconomic position may advance public health and clinical research and practice for firearm violence prevention.

Air quality and life expectancy in the United States: An analysis of the moderating effect of income inequality

Although studies have shown that air pollution can be devastating to population health, little is known about the health implications of the intersection of air pollution and income inequality. We investigate if air pollution is especially detrimental to the health of US state populations characterized by more inequitable distributions of income. In other words, are the populations of states with higher levels of income inequality especially vulnerable to similar levels of air pollution? We use two-way fixed-effects panel regression techniques to analyze longitudinal data for 49 US states and the District of Columbia (2000-2010) to model state-level life expectancy as a function of fine particulate matter, income inequality, and other state-level factors. We estimate models with interaction terms to formally assess whether the association between fine particulate matter and life expectancy varies by level of state income inequality. Across multiple life expectancy outcomes and additive models, states with higher PM_2.5 levels tend to exhibit lower average life expectancy. This general pattern is observed with our specifications for raw and weighted PM_2.5 and with adjustments for income share of the top 10%, total population, GDP per capita, median household income, median age, percent college degree or higher, percent black, and percent Hispanic/Latino. We also find that the association between state PM_2.5 levels and average life expectancy intensifies in states with higher levels of income inequality. More specifically, PM_2.5 levels are more detrimental to population life expectancy in states where a higher percentage of income is concentrated in the top 10% of the state income distribution. We discuss the implications of our results for future research in social epidemiology and environmental justice.

Area-level income inequality and oral health among Australian adults-A population-based multilevel study

Background

A lack of evidence exists on the association between area-level income inequality and oral health within Australia. This study examined associations between area-level income inequality and oral health outcomes (inadequate dentition (<21 teeth) and poor self-rated oral health) among Australian adults. Variations in the association between area-level income inequality and oral health outcomes according to area-level mean income were also assessed. Finally, household-income gradients in oral health outcomes according to area-level income inequality were compared.

Methods

For the analyses, data on Australian dentate adults (n = 5,165 nested in 435 Local Government Areas (LGAs)) was obtained from the National Dental Telephone Interview Survey-2013. Multilevel multivariable logistic regression models with random intercept and fixed slopes were fitted to test associations between area-level income inequality and oral health outcomes, examine variations in associations according to area-level mean income, and examine variations in household-income gradients in outcomes according to area-level income inequality. Covariates included age, sex, LGA-level mean weekly household income, geographic remoteness and household income.

Results

LGA-level income inequality was not associated with poor self-rated oral health and inversely associated with inadequate dentition (OR: 0.64; 95% CI: 0.48, 0.87) after adjusting for covariates. Inverse association between income inequality and inadequate dentition at the individual level was limited to LGAs within the highest tertile of mean weekly household income. Household income gradients in both outcomes showed poorer oral health at lower levels of household income. The household income gradients for inadequate dentition varied according to the LGA-level income inequality.

Conclusion

Findings suggest that income inequality at the LGA-level in Australia is not positively associated with poorer oral health outcomes. Inverse association between income inequality and inadequate dentition is likely due to the contextual differences between Australia and other high-income countries.

Socioeconomic status, health inequalities and non-communicable diseases: a systematic review

AIM

A comprehensive approach to health highlights its close relationship with the social and economic conditions, physical environment and individual lifestyles. However, this relationship is not exempt from methodological problems that may bias the establishment of direct effects between the variables studied. Thus, further research is necessary to investigate the role of socioeconomic variables, their composition and distribution according to health status, particularly on non-communicable diseases.

SUBJECTS AND METHODS

To shed light on this field, here a systematic review is performed using PubMed, the Cochrane Library and Web of Science. A 7-year retrospective horizon was considered until 21 July 2017.

RESULTS

Twenty-six papers were obtained from the database search. Additionally, results from "hand searching" were also included, where a wider horizon was considered. Five of the 26 studies analyzed used aggregated data compared to 21 using individual data. Eleven considered income as a study variable, while 17 analyzed the effect of income inequality on health status (2 of the studies considered both the absolute level and distribution of income). The most used indicator of inequality in the literature was the Gini index.

CONCLUSION

Although different types of analysis produce very different results concerning the role of health determinants, the general conclusion is that income distribution is related to health where it represents a measure of the differences in social class in the society. The effect of income inequality is to increase the gap between social classes or to widen differences in status.

Income inequality and foregone medical care in Europe during The Great Recession: multilevel analyses of EU-SILC surveys 2008-2013

BACKGROUND

The association between income inequality and societal performance has been intensely debated in recent decades. This paper reports how unmet need for medical care has changed in Europe during The Great Recession, and investigates whether countries with smaller income differences have been more successful than inegalitarian countries in protecting access to medical care during an economic crisis.

METHODS

Six waves of EU-SILC surveys (2008-2013) from 30 European countries were analyzed. Foregone medical care, defined as self-reported unmet need for medical care due to costs, waiting lists, or travel difficulties, was examined among respondents aged 30-59 years (N = 1.24 million). Countries' macro-economic situation was measured by Real Gross Domestic Product (GDP) per capita. The S80/S20 ratio indicated the country's level of income inequality. Equity issues were highlighted by separate analyses of disadvantaged respondents with limited economic resources and relatively poor health. Cross-tabulations and multilevel linear probability regression models were utilized.

RESULTS

Foregone medical care increased 2008-2013 in the majority of the 30 countries, especially among the disadvantaged parts of the population. For the disadvantaged, unmet need for medical care tended to be higher in countries with larger income inequalities, regardless of the average economic standard in terms of GDP per capita. Both for disadvantaged and for other parts of the samples, a decline in GDP had more severe effects on access in inegalitarian countries than in countries with less income inequality.

CONCLUSIONS

During The Great Recession, unmet need for medical care increased in Europe, and social inequalities in foregone medical care widened. Overall, countries with a more egalitarian income distribution have been more able to protect their populations, and especially disadvantaged groups, against deteriorated access to medical care when the country is confronted with an economic crisis.