James S. House

Income inequality and mortality: importance to health of individual income, psychosocial environment, or material conditions

Studies on the health effects of income inequality have generated great interest. The evidence on this association between countries is mixed,1–4 but income inequality and health have been linked within the United States,5–11 Britain,12 and Brazil.13 Questions remain over how to interpret these findings and the mechanisms involved. We discuss three interpretations of the association between income inequality and health: the individual income interpretation, the psychosocial environment interpretation, and the neo-material interpretation. #### Summary points Income inequality has generally been associated with differences in health A psychosocial interpretation of health inequalities, in terms of perceptions of relative disadvantage and the psychological consequences of inequality, raises several conceptual and empirical problems Income inequality is accompanied by many differences in conditions of life at the individual and population levels, which may adversely influence health Interpretation of links between income inequality and health must begin with the structural causes of inequalities, and not just focus on perceptions of that inequality Reducing health inequalities and improving public health in the 21st century requires strategic investment in neo-material conditions via more equitable distribution of public and private resources We reviewed the literature through traditional and electronic means and supplemented this with correlational analyses of gross domestic product and life expectancy and of income inequality and mortality trends based on data from the World Bank,14 the World Health Organization,15 and two British sources.16 17 According to the individual income interpretation, aggregate level associations between income inequality and health reflect only the individual level association between income and health. The curvilinear relation between income and health at the individual level 18 19 is a sufficient condition to produce health differences between populations with the same average income but different distributions of income.3 20 This interpretation assumes that determinants …

Social Support, Occupational Stress, and Health

The present paper is concerned with the buffering hypothesis that social support ameliorate. the impact of occupational stress on job-related strain and health. Previous studies of this hypothesis have yielded conflicting results. Our purpose, therefore, is twofold. First, we summarize the literature in this area and review several studies in detail, all of which found main effects of social support on perceived occupational stress and on some health outcome measures. Three of the studies were specifically designed to examine the buffering effects of support. Of the three, two found little or no evidence for buffering (LaRocco and Jones, 1978a; Pinneau, 1975), whereas the third reported buffering effects (House and Wells, 1978). Second, we attempt to reconcile these different conclusions by reanalyzing one data set-first analyzed by Caplan et al. (1975) and then by Pinneau (1975)-using a moderated regression technique identical to that used in the LaRocco and Jones (1978a) and House and Wells (1978) studies. The data usedfor this analysis consist of a randomly stratified sample of men from 23 occupations (N 636). Our review andfindings support the buffering hypothesis for mental and physical health variables (anxiety, depression, irritation, and somatic symptoms), but, as in the previous three studies, fail to support the buffering hypothesis in regard to job-related strains (job dissatisfaction, boredom, dissatisfaction with work load).

The social stratification of aging and health

The way health varies with age is importantly stratified by socioeconomic status (SES)--specifically, education and income. Prior theory and cross-sectional data suggest that among higher SES persons the onset of health problems is usually postponed until rather late in life, while health declines are prevalent in lower SES groups by middle age. Thus, SES differences in health are small in early adulthood, but increase with age until relatively late in life, when they diminish due to selection or greater equalization of health risks and protections. The present paper strengthens our causal and interpretive understanding of these phenomena by showing: (1) that results previously reported for indices of SES hold separately for education and income; (2) that the interaction between age and SES (i.e., education or income) in predicting health can be substantially explained by the greater exposure of lower SES persons to a wide range of psychosocial risk factors to health, especially in middle and early old age, and, to a lesser degree, the greater impact of these risk factors on health with age; and (3) that results (1) and (2) generally hold in short-term longitudinal as well as in cross-sectional data. Implications for science and policy in the areas of aging, health, and social stratification are discussed.

Age, Socioeconomic Status, and Health

Analysts dispute what roles biomedical, psychosocial, and other factors play in determining the duration of morbidity and disability over the life course. Cross-sectional data from two national surveys of adults aged 25 years and over not only show, however, that age and socioeconomic status (SES) are significant predictors of self-reported physical health; they also demonstrate that the relation of age to health varies with SES features. Longitudinal research is needed to test the finding that enduring functional limitations in terms of time are actually compressed in higher SES groups. To improve well-being in our society, moreover, requires specifying why SES differences occur, and perhaps ultimately reducing socioeconomic inequality itself.

The effect of social relationships on psychological well-being: Are men and women really so different?

We assess evidence for gender differences across a range of relationships and consider whether the form and quality of these relationships affect the psychological functioning of men and women differently. Data from a national panel survey provide consistent evidence that mens and womens relationships differ. However, we find little evidence for the theoretical argument that women are more psychologically reactive than men to the quality of their relationships : Supportive relationships are associated with low levels of psychological distress, while strained relationships are associated with high levels of distress for women and for men. However, if women did not have higher levels of social involvement than men, they would exhibit even higher levels of distress relative to men than they currently do. We find little evidence for the assertion that men and women react to strained relationships in gender-specific ways-for example, with alcohol consumption versus depression

Income dynamics and adult mortality in the United States, 1972 through 1989.

OBJECTIVES The aim of this study was to examine relationships between income and mortality, focusing on the predictive utility of single-year and multiyear measures of income, the shape of the income gradient in mortality, trends in this gradient over time, the impact of income change on mortality, and the joint effects of income and age, race, and sex on mortality risk. METHODS Data were taken from the Panel Study of Income Dynamics for the years 1968 through 1989. Fourteen 10-year panels were constructed in which predictors were measured over the first 5 years and vital status over the subsequent 5 years. The panels were pooled and logistic regression was used in the analysis. RESULTS Income level was a strong predictor of mortality, especially for persons under the age of 65 years. Persistent low income was particularly consequential for mortality. Income instability was also important among middle-income individuals. Single-year and multiyear income measures had comparable predictive power. All effects persisted after adjustment for education and initial health status. CONCLUSIONS The issues of low income and income instability should be addressed in population health policy.

Chronic job insecurity among automobile workers: Effects on job satisfaction and health

Work conditions characterized by uncertainty and ambiguity are potential stressors for employees. One such stressor is job insecurity. This longitudinal study of 207 automobile manufacturing workers indicates that chronic job insecurity is predictive of changes over time in both job satisfaction and physical symptoms. Extended periods of job insecurity decrease job satisfaction and increase physical symptomatology, over and above the effects of job insecurity at any single point in time. These results indicate that job insecurity acts as a chronic stressor whose effects become more potent as the time of exposure increases. Worksite health professionals should develop strategies for reducing the impact of job insecurity on employee well-being, particularly in industries where employment opportunities are declining.

Continuity and Change in the Social Stratification of Aging and Health Over the Life Course: Evidence From a Nationally Representative Longitudinal Study From 1986 to 2001/2002 (Americans' Changing Lives Study)

Objectives. This article overviews previously published and ongoing research from the Americans’ Changing Lives (ACL) Study, a longitudinal study of a nationally representative sample of 3,617 adults aged 25 years and older when first interviewed in 1986, focusing on socioeconomic disparities in the way health changes with age during middle and later life, especially in terms of compression of morbidity/functional limitations. Methods. A variety of descriptive and multivariate regression and growth curve analyses are done on the ACL sample, now surveyed over four waves spanning 15.5 years between 1986 and 2001/2002 with continuing mortality ascertainment via the National Death Index, death certificate searches, and informant reports. Results. Both cross-sectional and longitudinal analyses indicate that socioeconomic disparities in health are small in early adulthood, increase through middle and early old age, and then lessen again in later old age. In other terms, compression of morbidity/functional limitations into the later stages of the life course is realized to a much greater degree among the better educated compared with the less educated. Cross-sectional evidence suggests that this reflects differential exposure to or experience of a wide range of psychosocial, environmental, and biomedical risk factors for health (and perhaps their differential impact at different ages and life stages), as well as variations in biological robustness and frailty and also perhaps in the strength of social welfare supports for health at different life stages. Longitudinal analyses reveal several new insights: (a) The flow of causality is much greater from socioeconomic position to health than vice versa; (b) education plays a greater role relative to income in the onset of functional limitations, whereas income has much stronger effects on their progression or course; and (c) educational disparities in the onset and hence of compression of functional limitations over the life course have increased strikingly in later middle and early old age (ages 55‐84 years) since 1986. Discussion. The results indicate that understanding and alleviating social disparities in health are both theoretically and methodologically quintessential problems of life course analysis and research.

SES Differentials in Health by Age and Alternative Indicators of SES

Despite the general persistence and even increase of strong socioeconomic status (SES) differentials in health in the United States, research suggests that SES differentials in health may diminish or become nonexistent at older ages. However, most research has used only limited measures of SES (e.g. education, income), and has not thoroughly investigated intra-elderly age differences in this trend. The current study investigates how SES differentials in health vary by age in the United States, using fairly detailed age categories (through ages 85+), and 2 alternative indicators (home ownership and liquid assets) of a major additional dimension of SES, financial assets, which may be especially important at older ages. We address (a) how strongly financial assets are associated with health, considered both alone and net of education and income; (b) if the health effects of financial assets vary by age; and, more specifically, (c) if their effects are especially pronounced in older age, again considered both alone and net of or relative to education and income. Results show that financial assets, especially liquid assets, considered both alone and net of education and income, are associated with health throughout adulthood and old age, at least until ages 85+. Furthermore, financial assets remain associated with health until quite late in life and become more important relative to education and income at older ages for some measures of health.

Social isolation kills, but how and why?

The article by Brummett et al. (1) provides another confirmation of the deleterious effects on health of social isolation, first recognized in epidemiologic research of the late 1970s and 1980s and replicated and extended for more than a decade since then (2–4). Social isolation has been shown repeatedly to prospectively predict mortality and serious morbidity both in general population samples (2) and in individuals with established morbidity (3, 4), especially coronary heart disease (1). The magnitude of risk associated with social isolation is comparable with that of cigarette smoking and other major biomedical and psychosocial risk factors. However, our understanding of how and why social isolation is risky for health—or conversely—how and why social ties and relationships are protective of health, still remains quite limited. Brummett et al. (1) contribute importantly to increasing such understanding, but also fail to capitalize fully on opportunities to contribute even more. This article by Brummett et al. (1) is noteworthy because it shows the impact of social isolation on mortality in an important clinical population with a very extensive set of adjustments for other sociodemographic, psychosocial, and biomedical predictors of mortality. It also carefully explores the functional form of the prospective relationship of social ties to mortality, adding to the evidence that the form of the relationship is nonlinear, with social isolation producing a twoto three-fold increase in risk of mortality, but with little or no variation across moderate to high levels of social relationships. That is, a serious deficiency of social relationships is risky to health, but once the deficiency is removed, adding additional relationships to a social network does not produce substantial or significant increases in health and well-being contrary to the impression left by some arguments for the importance of social relationships to the well-being of individuals and societies (5). Properly understanding the functional form of the relationship has important implications for both social policy and clinical practice. It may be important to try to ensure that all individuals have meaningful social ties with at least one or a few other individuals, and this is especially true of individuals whose health is already compromised by significant morbidity, especially coronary heart disease. However, trying to enhance further the social network of nonisolated individuals is likely to have little or no additional benefits, at least for health. Nor does it seem that any particular type of relationship is crucial. Rather, meaningful social ties seem to be functional alternatives to each other. Where a person has regular interaction with a spouse, other relatives, or friends seems less important than that the person has one or more of these social ties. It is often assumed that it is the supportiveness of social relationships that explains the health-enhancing effects of social relationships. It is certainly reasonable and consistent with existing evidence that the provision of various kinds of emotional and instrumental support is one of the ways in which social relationships benefit health (4, 6). However, most studies of the health impact of social relationships on health fail to evaluate the extent to which support or any other attribute or correlate of relationships can account for the robust and substantial impact of social relationships on health. Brummett et al. (1) seem to have some of the best data yet available for investigating the issue, but fail to capitalize on these data as fully as they could and should. They show that social isolation is unrelated to a wide range of measures of demographic factors, disease severity, physical functioning, and psychological distress. Hence, such factors can not account for or explain the substantial deleterious effects of social isolation. However, they also show that isolated individuals report fewer interactions with others, fewer sources of psychological/emotional and instrumental support, and lower levels of religious activity. The obvious question is whether adjusting for one or more of these factors reduces the association of social relationships/ isolation with health. Which factors constitute the active ingredient in social isolation producing its deleterious effects on health? Few other studies have the combination of measures available to Brummett et al. (1); thus, I hope in the future they will do the type of analyses suggested here. Most of their data seem oriented to testing the hypothesis that it is the supportiveness of relationships that explain their effects. However, there are other plausible hypotheses that also deserve to be tested by Brummett et al. (1) or others (2, 4). First is the idea that isolation from others is anxiety arousing or stressful in and of itself, producing physiological arousal and changes, which if prolonged, can produce serious mor-