Millions of dollars and decades of hard work have gone into trying to eradicate disparities in health and health care that are related to differences in race, ethnicity and income with extremely poor results. The question, of course, is why? "To begin with, our model of what contributes to health disparities is far too simple," advises James S. Jackson, PhD, a social psychologist and 2009 Robert Wood Johnson Foundation (RWJF) Investigator in Health Policy Research, who is a leader in the field.
"The model that most researchers use is essentially incomplete," Jackson continues. "As a result, we've become very good at describing disparities, but we are having a more difficult time eliminating disparities in physical health status, even as we attempt to address differences in health care." The Healthy People 2010 report, published by the U.S. Department of Health and Human Services (HHS), illustrates Jackson's point. The document chronicles progress, over 10 years, on 773 indicators of physical and mental health, including life expectancy, access to care and insurance status. HHS found, however, that in the indicators related to disparities, there was no change in 80 percent of the variables measured and disparities actually increased in 13 percent of the categories. "The answers to these problems are complex and multi-faceted," Jackson says. "The current approach, for example, fails to consider the powerful influences that chronic stressors and active coping with that stress have on physical morbidity and mortality."
A Thousand Tiny Cuts
Health professionals attempting to address disparities frequently overlook the point that "disparities are a function of lived lives, resulting from multiple events that unfold over the life course," explains Jackson, who is also director and research professor at the Institute for Social Research at the University of Michigan.
"Environmental stressors, accumulated and responded to over time, are a major source of health disparities. The law of small effects is very important and suggests that there is no one, single factor contributing to a disparity in a certain disease. Instead, it's a group of small differences that include genes, behavior, culture, socioeconomic status, institutional racism—a host of factors that accumulate and interact over a person's life course. You must look at stressors such as a lack of neighborhood resources and jobs, pollutants, crime, poor housing and poor services. All of these things working in concert create the environments for poor health and the poor health behaviors that people may engage in to cope with the stressors in their lives."
From this perspective, it is easier to understand why obesity, to name one pressing health issue, cannot easily be solved by just providing a source of healthy food in an underserved community. That act alone will not achieve the needed reductions in weight or hypertension by changing unhealthy eating patterns, because critical connections are missing. "You must consider the links that connect stress, mental health and physical health," Jackson says.
"For certain groups in America, who reside in underserved neighborhoods, there are constant, chronic stressors bearing down on the population," Jackson explains. "There's a constant activation of the HPA (hypothalamic-pituitary-adrenal) Axis—[a series of interactions in the body that are triggered by stress and that effect many parts of the body, including the immune system and emotions]—which are detrimental to physical health. In addition, people may attempt to actively cope with the symptoms of stress, either consciously or unconsciously, by smoking, drinking, eating comfort foods or using drugs—substances that are available in large quantities in poor neighborhoods."
Far from blaming all individuals who experience disparities for their plight, Jackson says, we need to understand that "these are not simply hedonic behaviors; these are physiologically effective, but maladaptive ways of dealing with stressful environments."
Race Matters: The African American Example
Jackson's theory also differs from traditional approaches to disparities in the way that he views race. "Race is a complex construct, but it's more of a destination than a variable set at birth. It's defined not only by skin color but more by the nature of exposures to social and environmental risks over the life course. These experiences accumulate, and among the more disadvantaged racial groups in society, poor health often manifests in middle age. In more privileged and thus protected racial groups, these experiences are moderated and buffered by resources so that stress-related health problems occur later in life."
In addition, Jackson notes, population-level disparities in physical health favor Whites, while disparities in mental health favor Blacks. "For Blacks who are living under highly stressful conditions, engaging in bad health behaviors harms physical health, but may be protective against stress-related disorders, like major depression," Jackson says. "While this outcome is not the same among higher income Whites, it is similar among Whites whose life course exposures and experiences are similar to the circumstances that a large number of Blacks face in this society. It's then easier to see how living in consistently stressful environments contributes to persistent physical health challenges that grow more severe as people age, regardless of their racial categorization."
A More Effective Approach
Solutions to these difficult problems may be found in "relevant policies based in an understanding of how disparities in mental and physical health combine," says Jackson, who recently spoke about his theory to an enthusiastic audience of students at the RWJF Center for Health Policy at Meharry Medical College. "In my upcoming book, which is part of my work as an RWJF Investigator, I will explore how policy-makers, researchers, clinicians and others can create programs that are genuinely effective at reducing health disparities."
RWJF’s Investigator Awards in Health Policy Research provide funding to highly qualified individuals undertaking broad studies of the most challenging health, health care and health policy issues facing America. Grants are awarded to Investigators from a wide range of disciplines. Their work reflects thinking that is creative and conceptual and crosses disciplinary boundaries in search of knowledge and innovative solutions to critical health problems and policy issues.