Interview:

'It's Not Just Poverty'

Nancy Adler, PhD, director of health psychology at the University of California-San Francisco, is principal investigator in a major effort to identify the mechanisms through which socioeconomic status impacts health. The study, launched in January 1997 with a four-year $4.6 million grant from the John D. and Catherine T. MacArthur Foundation, involves 10 other scientists from six disciplines: physicians, epidemiologists, neuroscientists, psychologists, a sociologist, and an anthropologist. (Contact: 415-476-7759) We asked about the project's objectives.

The critical question for us is: How does socioeconomic status get into the body? We are trying to understand the physiological pathways by which socioeconomic status affects health. We know it isn't simply the deprivation that goes with poverty that affects health. Even at the upper socioeconomic levels, where everyone has good housing and adequate nutrition and their physiological needs are met, there is still a difference in health and well-being between those at the top and those just near the top, and there's a gradient that follows on down to the bottom of the economic ladder.

When people think about socioeconomic status and health, they assume it's abject poverty, that there's a threshold at the poverty level, a point above which your needs are met and everything should flatten out. But that's not how it is. The relationship of health and status just keeps on going as you move up and down the scale.

Q. Does it apply across all diseases?

A. Just about all. It's pervasive across most disorders and diseases - arthritis, stroke, depression, and anxiety disorders, for example. Our ability to study this has been limited because so much of what science has been focused on are particular diseases. It's even reflected in how the National Institutes of Health are organized around specific diseases. Yet, what socioeconomic status may do is create the conditions in which we become more vulnerable to a range of different diseases. There's an important exception: with breast cancer, socioeconomic status appears to work in reverse. Breast cancer ismore frequent in women of higher socioeconomic status. That's probably a function of delayed childbearing, which is a major risk factor. But once you do get breast cancer, the higher your status, the longer you survive.

Q. What seems to explain the links?

A. One pathway is clearly health behaviors - lifestyle differences such as diet, exercise, and smoking. But there is still a great deal that is not yet explained by health behaviors.

The one we are particularly focusing on is the differential exposure to stress and the reaction of the body to stress. Also on the list would be exposures to environmental toxins. And a fourth is access to care and the quality of health care you get: we know it's important but it just doesn't account for a lot of the variance in health.

Q. Isn't it the first thing most people think of?

A. Most people assume access to health care explains everything. But you still find a strong association between socioeconomic status and health outcomes in societies that have universal health care. It's just as strong in England as in the United States, despite England's National Health Service.

Q. And beyond access to care?

A. There's this gnawing issue of social ordering, about being higher or lower in the social hierarchy, that affects health. You find it no matter what indicator you use, whether you use income, occupation, or education. We're studying this in animals, because animals on the low end of their hierarchy also display worse health than higher-ranked animals.

Q. If most of us are almost certain to be lower in the social hierarchy than others, and if that affects our health, how do we deal with it?

A. If we're right that one of the key mechanisms is exposure to stress that results from the disparity in socioeconomic status, then how we help people deal with the stresses that are inevitably going to be part of life may be very helpful. We don't have those answers yet.

One concept is what we call reactive responding. The lower you are in the socioeconomic hierarchy, the more you have to respond to stimuli that are immediate and emotion-driven and that don't give you much chance to plan your response. Often, the stimuli involve some kind of threat. So your immediate response is quite negative.

You develop negative expectations that may become self-fulfilling prophecies, which themselves create more physiological arousal. The system can become hyperactive and not turn off. Or, it may give up and not turn on at all, so you have almost no reaction to even serious threats. That also turns down the immune response and puts you at risk. We need to understand a lot more about the mechanisms involved

Interview #2: Poverty's Lasting 'Footprints'

George A. Kaplan, PhD, has explored the pathways between poverty and poor health for two decades. He was chief of the Human Population Laboratory of the Public Health Institute at Berkeley and taught at the University of California-Berkeley until last summer, when he became chair of the Department of Epidemiology at the University of Michigan. For 16 years he also directed the Alameda County (CA) study,8 which began in 1965 and repeatedly surveyed a group of 7,000 adults about their health. We asked about his most recent findings. (Contact: 313-764-5435)

We've learned that the health of older individuals today shows the strong footprints of their economic histories from decades earlier. My colleagues and I asked how many times over the last 29 years they had been living at income levels below 200 percent of the poverty line, which used to be the standard cutoff for "disadvantaged" levels. Then we looked at their current health and found that the cumulative burden of economic disadvantage was visible in all of the outcomes.

People who had been below 200 percent of the poverty line on three occasions were now experiencing three to four times the risk of having low levels of physical functioning, compared to those who reported no dips below that poverty threshold. They had three times the risk of being clinically depressed, almost five times the risk of reduced cognitive functioning, and twice the likelihood of being socially isolated. All of these conditions represent important health problems that reduce both length and quality of life.

Q. Was it only people who were continually exposed to poverty who were at risk?

A. No, there was a stepwise relationship. People who reported being below 200 percent of poverty level just one time were next best to those who never went below that threshold, and then the picture became progressively worse as people reported more and more periods below that level.

Q. Is the problem compounded because the culture of poverty seems to be passed from generation to generation?

A. It's more than cultural. We see the intrauterine transmission of social class as a biological phenomenon: children born with lower birth weights, less than optimal placental weight and head circumference have worse futures. These oftenrepresent the effects of prenatal malnutrition and poor medical care, stress and a whole variety of other things experienced by people who are poor. We think that what these studies are showing is the tracking of disadvantage through the uterus into birth outcomes and subsequent disease.

Q. Isn't it now well established that poor people have poor health?

A. It isn't that simple. In recent years there's new literature that shows that it's not just how much money the people in a particular area have that predicts how healthy that population will be. It's also how fairly the income and wealth are distributed. In geographic areas with more egalitarian distribution of income there's better health, and that effect is actually independent of the average level of income or the relative poverty rates in the area.

Poorer cities with wealthy suburbs, like Detroit or Washington, D.C., suffer because of the flow of capital goods and resources and productivity to the suburbs. You see that reflected in the poorer health of the people who are in the cities.

We think this has profound implications for public health, as well as for health care and public policy. In fact, we might say that economic policy is a good part of health policy, that changes in the economic well-being of people seem to be strongly associated with changes in their health status. In many cases, these effects are considerably larger than any other factors we know about.

Q. Are there broader health implications as well?

A. It's important to remember that the fairness of the distribution of wealth, that living in a society where there is less inequality and therefore less stress, may benefit everybody, not just the poor. Societies with less inequality invest more in the development of human, physical, and social capital. For example, they spend more on education and on programs to help the poor. This makes for increased productivity and security, lowers crime, and increases social cohesion for everyone. That could translate into better health.

Stress Overloads

Researchers are developing ways of measuring wear and tear on the body that results from environmental stressors (such as might be caused by low socioeconomic status) and the stress of major life events, trauma or abuse - all of which can have long term health consequences.

Bruce McEwen, PhD, of the Harold and Margaret Milliken Hatch Laboratory of Neuroendocrinology, Rockefeller University, and a member of the MacArthur Foundation's Research Network on Socioeconomic Status and Health, is part of a team developing a measurement system based on the concept of "allostasis."

McEwen describes allostasis as the process by which the body secretes substances, mainly hormones, that help the body adapt to stress. The allostatic systems* protect the body by responding to internal and external stress.

"But when these systems are in fact operating inefficiently, or fail to shut off, or are simply stimulated too frequently, the body is exposed to its own stress hormones, and that's what we call allostatic load."

McEwen discusses the research on allostatic load in the January 15, 1998, issue of the New England Journal of Medicine.(13) Noting that it has been best studied in the cardiovascular system's role in obesity and hypertension, McEwen cites an unpublished study by the MacArthur Research Network on Successful Aging. That research tracked the results of eight measures of allostatic systems activity from 1988 to 1991. Individuals who were healthy in 1988 but had the highest allostatic load scores also had the highest probability of cardiovascular disease in 1991, and the greatest decline in cognitive measures and physical functioning.

* The autonomic nervous system, the hypothal-mic-pituitary-adrenal axis, and cardiovascular, metabolic and immune systems.

(Contact : 212-327-8624)

For Richer, For Poorer...

At each step down the employment and social scale from rich to poor, health outcomes worsen. The clearest demonstration of that came in two studies of British government office workers. The first, started in 1967, established the link between job status and mortality from a wide range of diseases. Michael G. Marmot, who heads the Department of Epidemiology at London Medical School, wrote later:

"In this relatively homogeneous population ...each group had a higher mortality rate than the group one step higher in the hierarchy. The difference in mortality was threefold between the highest and lowest positions in the hierarchy. The question is not why people at the bottom have worse health, but why social differences in health are spread across the whole of society."(12)

In the 1980s, Marmot and his colleagues examined links between job status and symptoms of poor health in another 10,314 British civil servants.(11) Some findings:

• Fewer of those in lower status jobs said they had control over their working lives or were satisfied with their situations.
• Social activity differed. Those with lower status jobs had less - and less satisfactory - social support than those above them on the employment ladder.
• Lower status jobholders were likely to report two or more of eight potentially stressful life events in the previous year.
• The risk factor that differed most among employment grades was smoking; men in the lowest grades were about four times more likely to be smokers than those in the highest. They also exercised less and ate fewer healthy foods.

"There is no equivalent study in the United States, where you have such clear gradations within the same organization," says Dr. Nancy Adler, of the University of California-San Francisco. "That's one of the things we're looking at."

Investing in Health

Ichiro Kawachi, MD, PhD, and Bruce P. Kennedy, PhD, of the Harvard School of Public Health, received a 1996 Robert Wood Johnson Foundation Award to study the links between health and income and social capital. Excerpts from their writings:

'Human Capital' - "Income distribution may be a proxy for other social indicators, such as degree of investment in human capital. Communities that tolerate large degrees of inequality in income may ... (also) tend to underinvest in social goods such as public education or accessible health care."(7)

'Social Capital' - In 39 states, researchers asked residents whether "most people can be trusted" and whether they belonged to church, sports, fraternal, or other organizations - two measures of "social capital." In each state: the greater the mistrust and the fewer who belonged to organizations, the greater the income disparity. "In turn, both ... (also) strongly correlated with overall mortality. The effect of income inequality on mortality thus seemed to be mediated through the withering of social capital." (6)

The 'Robin Hood Index' - One study measured income inequality by state using the "Robin Hood Index," the proportion of aggregate income that needs to be redistributed to achieve income equality. It found: "A 1 percent rise in the Robin Hood Index was associated with an excess mortality of 21.7 deaths per 100,000...suggesting that even a modest reduction in inequality could have an important impact on population health. The maldistribution of income was (also) related to infant mortality, homicides, and deaths from cardiovascular disease and neoplasms."(6)

-Kawachi: 617-432-0235 -Kennedy: 617-432-0081

'Race Matters'

Poor blacks and poor whites report comp-arable levels of ill health, but blacks are disproportionately represented among the poor, and thus suffer disproportionately the health consequences of poverty, compounded by the stresses of racism.

According to Dr. David R. Williams and colleagues at the University of Michigan, and Dr. Norman B. Anderson, Director of the Office of Behavioral and Social Sciences Research at the National Institutes of Health, writing in the Journal of Health Psychology:

"Our analyses document that race matters a lot in terms of health. Moreover, the sources of racial disparities are not unknown, individual, or obscure. They can be traced to inequalities that have been created and maintained by the economic, legal, and political structures of society. These systems, and not individual beliefs and behavior, are the fundamental causes of racial and socioeconomic inequalities in health. Eliminating these disparities will thus require changes in the fundamental social systems in society."(14)

-Williams: 313-936-0649
-Anderson: 301-402-1146

The Research

1. Adler, NE, et al., (January 1994), "Socioeconomic Status and Health: The Challenge of the Gradient," American Psychologist, pp. 15-24.

2. Adler, NE, et al., (June 23/30, 1993), "Socioeconmic Inequalities in Health: No Easy Solution," JAMA, pp. 3140-3145.

3. Anderson, NB, and Armstead, CA, (May/June 1995), "Toward Understanding the Association of Socioeconomic Status and Health: A New Challenge for the Biopsychosocial Approach," Psychosomatic Medicine, pp. 213-225.

4. Center on Budget and Policy Priorities, (December 16, 1997), "Pulling Apart: A State-by-State Analysis of Income Trends." Contact: 202-408-1080.

5. Kaplan, GA, et al., (April 20, 1996), "Inequality in Income and Mortality in the United States: Analysis of Mortality and Potential Pathways," British Medical Journal, pp. 999-1003.

6. Kawachi, I, and Kennedy, BP, (April 5, 1997), "Health and Social Cohesion: Why Care About Income Inequality," British Medical Journal, pp. 1037-1040.

7. Kennedy, BP, and Kawachi, I, (April 20, 1996), "Income Distribution and Mortality: Cross Sectional Ecological Study of the Robin Hood Index in the United States," British Medical Journal, pp. 1004-1007.

8. Lynch, JW, Kaplan, GA, et al., (December 25, 1997), "Cumulative Impact on Sustained Economic Hardship of Physical, Cognitive, Psychological and Social Functioning," New England Journal of Medicine, pp. 1889-1895. Contact - Lynch: 313-647-9548

9. Lynch, J, et al., (1997), "Workplace Demands, Economic Reward and Progression of Carotid Atherosclerosis," Circulation, vol. 96, pp. 302-307.

10. Lynch, JW, Kaplan, GA, et al., (1997), "Understanding How Inequality in the Distribution of Income Affects Health," Journal of Health Psychology, pp. 297-314.

11. Marmot, MG, et al., (June 8, 1991), "Health Inequalities Among British Civil Servants: the Whitehall II Study," The Lancet, pp. 1387-1393.

12. Marmot, MG, (1994), "Social Differentials in Health Within and Between Populations," in Health and Wealth, published as vol. 123, no. 4, Proceedings of the American Academy of Arts and Sciences, Daedalus.

13. McEwen, BS (January 15, 1998), "Protective and Damaging Effects of Stress Mediators: Allostasis and Allostatic Load," New England Journal of Medicine, pp. 171-179.

14. Williams, DR, Yan Yu, Jackson, JS, and Anderson, NB, (1997), "Racial Differences in Physical and Mental Health: Socioeconomic Status, Stress and Discrimination," Journal of Health Psychology, vol. 2(3), pp. 335-351.

This report was prepared with assistance from:

Academy of Behavioral Medicine Research
Academy of Psychosomatic Medicine
American College of Neuropsychopharmacology
American Psychiatric Association
American Psychological Association
American Psychological Association-Division 38
American Psychosomatic Society
American Society of Psychiatric Oncology
College on Problems of Drug Dependence
International Psycho-Oncology Society
International Society for Traumatic Stress Studies
Society of Behavioral Medicine
Society for Developmental and Behavioral Pediatrics
Society for Public Health Education

The Center for the Advancement of Health is a health policy institute founded by the John D. and Catherine T. MacArthur Foundation and the Nathan Cummings Foundation. It works to incorporate into standard health care those proven strategies that recognize and respond to how profoundly our attitudes, emotions, behaviors, social relations and economic status impact the onset of some diseases, the progression of many and the management of nearly all. Facts of Life is funded in part by the Fetzer Institute.

For more information contact:
Petrina Chong Communications Director
Phone: 202.387.2829
E-mail Petrina Chong

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