Research also reveals that pathogenic factors linked to race continue to affect health even when socioeconomic status (SES) is controlled. In national data there are residual racial differences in health at every level of SES for multiple indicators of health status, including self-rated health, heart disease mortality, hypertension and obesity (Pamuk et al. 1998). This pattern exists for a broad range of other outcomes. A striking example comes from national data on infant mortality by mothers’ education for all women age 20 years and older. African American women with a college degree or more education have a higher rate of infant mortality than white, Hispanic (or Latino), and Asian and Pacific Islander women who have not completed high school (Pamuk et al. 1998). Further evidence of the markedly elevated disease risk for African Americans comes from national data on chronic disease risk factors for blacks, whites and Hispanics age 40 and over (Crimmins et al. 2007). This study assessed indicators of blood pressure risk (systolic, diastolic, and pulse rate), inflammation risk (C-reactive protein, fibrinogen, albumin) and metabolic risk (total cholesterol, HDL cholesterol, BMI and glycated hemoglobin). A summary indicator of total risk counted how many of these 10 risk factors were outside of the normal range. This study found that even after adjustment for income, education, gender and age, blacks had higher scores on blood pressure, inflammation, and total risk. Importantly, blacks maintained a higher risk profile even after adjusting for health behaviors (smoking, poor diet, physical activity and access to care).

Perceived racial or ethnic discrimination is one aspect of racism that is increasingly receiving empirical attention as a class of stressors that could have consequences for health and for understanding disparities in health. This is consistent with broader interest in the role of stress as a determinant of social disparities in health (Pearlin et al. 2005). Stress appears to accelerate cellular aging (Epel et al. 2006) and the chronic stressors triggered by multiple environmental assaults can lead to wear and tear on the body that can dysregulate multiple biological systems and lead to premature illness and mortality (Seeman et al. 2004). A word about terminology—in this paper, we use the terms discrimination, perceived discrimination, interpersonal discrimination and self reported discrimination interchangeably. We also use the term racial discrimination to refer to both racial and ethnic discrimination.

There has long been interest in the relationship between discrimination and blood pressure (Williams and Neighbors 2001; Brondolo et al. 2003), as well as, cardiovascular disease more broadly (Wyatt et al. 2003). Table 1 lists eight recent studies that use laboratory experiments to expose individuals to analogues of racist events. The studies of cardiovascular reactivity find that acute experiences of stress continue to be related to increases in blood pressure reactivity in the laboratory setting. However, our understanding of the relationship between exposure to discrimination and the sustained elevation of blood pressure remains elusive. In recent studies, the patterns remain complex and unclear. While one study found a U-shaped association between discrimination and systolic blood pressure among Latinos and African Americans in New Hampshire (Ryan et al. 2006), some other studies have not found an association between perceived discrimination and blood pressure. This includes analyses of 3,300 middle-aged women in the MESA study (Brown et al. 2006). In a study of black and white adolescents, unfair treatment attributed to race was unrelated to ambulatory blood pressure, but unfair treatment due to physical appearance was (Matthews et al. 2005). Table 1 uses the term “conditional association” to indicate the absence of an association between discrimination and health in the overall sample, but with the existence of an association only for some sub-group. This pattern dominates the recent studies of discrimination and blood pressure. In analyses of 2,316 cases of incident hypertension in the Black Women’s Health Study (BWHS, Cozier et al. 2006), although discrimination was unrelated to incident hypertension in the total sample, it was positively related among women born outside of the U.S. In the Metro Atlanta Heart Disease Study, although discrimination was unrelated to blood pressure, high levels of stress due to discrimination were predictive of increased hypertension risk (Davis et al. 2005). Moreover, some of the conditional findings are counterintuitive. For example, in studies of black adolescents, discrimination was inversely related to blood pressure only among those who responded to discrimination with a passive coping style (Clark and Gochett 2006) or among those who were low on trait anger (Clark 2006a).

A broad range of physical health outcomes have been considered in the 21 recent studies listed in Table 1. Several large cross-sectional studies have found a positive association between discrimination and chronic health conditions or other self-reported indicators of ill-health. These include a national study of Asian Americans (Gee et al. 2007a), a study of Filipino Americans in San Francisco and Hawaii (Gee et al. 2006a), an African American sample in the CARDIA study (Borrell et al. 2006), and a national study in New Zealand (Harris et al. 2006b). In the New Zealand study a dose–response relationship was observed between perceived discrimination and each of the five indicators of health: self-rated health, physical functioning, mental health, cigarette smoking, and self-reported cardiovascular disease (Harris et al. 2006b) Other cross-sectional studies have found self-reported discrimination related to abdominal fat (Vines et al. 2007), hemoglobin A1c (Piette et al. 2006), poorer sexual functioning (Zamboni and Crawford 2007), nutritional risk among Black men (Locher et al. 2005) less stage 4 sleep (i.e., “deep,” or slow-wave sleep) and physical fatigue (Thomas et al. 2006). Longitudinal analyses of the large cohort of the BWHS have found a positive association between discrimination and the incidence of uterine myomas (fibroids) (Wise et al. 2007) and the incidence of breast cancer (Taylor et al. 2007). Other prospective analyses indicate that perceived discrimination predicts coronary artery calcification (Lewis et al. 2006) and changes in self-rated health (Schulz et al. 2006a).

Table 1 list 19 studies that have examined the extent to which reported experiences of discrimination can shape health care seeking and adherence behaviors. Some studies have focused on perceived discrimination in general while others have attended to perceptions of bias within the health care context. While perceptions of racism were unrelated to delayed seeking of treatment in a small study of African Americans with an acute myocardial infarction (Banks and Dracup 2006), it has been associated with delays or failure to seek treatment for less severe conditions in the U.S. (Facione and Facione 2007; Van Houtven et al. 2005; Wagner and Abbott 2007; Casagrande et al. 2007) and Sweden (Wamala et al. 2007a). However, the findings have not been uniform with discrimination unrelated to cancer screening (Dailey et al. 2007; Hoyo et al. 2005) and the use of preventive care (Fowler-Brown et al. 2006) in some studies. Perceived discrimination has also been associated with the failure to seek preventative services such as cholesterol testing, hemoglobin A1c testing and eye exams for diabetes and flu shots (Trivedi and Ayanian 2006) and the use of alternative care instead of conventional care (Bazargan et al. 2005). Several studies have also found an inverse association between discrimination and satisfaction with care among African Americans and Whites (Benkert et al. 2006; Fowler-Brown et al. 2006) and Korean Americans (Jang et al. 2005).

Earlier research had also indicated an association between discrimination and cigarette smoking and alcohol use. Recent studies reveal that perceived discrimination is associated with an increased risk of multiple substances, such as marijuana, inhalants and cocaine among middle school students (Choi et al. 2006). In the CARDIA study of young adults, discrimination was associated with marijuana, tobacco and alcohol use, but not cocaine use, among black but not white participants (Borrell et al. 2006). Similarly, both chronic and acute racial discrimination were associated with prescription drug use, illicit drug use and alcohol dependence among Filipino adults in San Francisco and Honolulu (Gee et al. 2007a). Other U.S. studies continue to find positive associations between discrimination and tobacco (Landrine et al. 2006; Krieger et al. 2005; Bennett et al. 2005) and alcohol use (Terrell et al. 2006). Studies from South Africa also find that perceived discrimination is positively associated with cigarette smoking (Brook et al. 2006b) and HIV risk behavior (Kalichman et al. 2006).

Another striking pattern in the current research is the broader range of contexts that have been considered. The earliest studies of discrimination and health disproportionately focused on the African American population. Recent studies have included all of the other racial/ethnic populations in the U.S. with several studies focusing on Asian American populations (Gee et al. 2006a, 2007a, b, c; Lam 2007; Jang et al. 2005). In recent years, studies have also utilized national samples in New Zealand (Harris et al. 2006a, b) and Sweden (Wamala et al. 2007a). Studies from Australia continue to examine the association between discrimination and Aboriginal health (Larson et al. 2007) and studies from the U.K. have examined discrimination and health among African-Caribbean, Bangladeshi, and White adults (Wadsworth et al. 2007), British Muslims (Sheridan 2006), minority ethnic teachers (Miller and Travers 2005); and multiple ethnic immigrant adults (Bhui et al. 2005; Karlsen et al. 2005). Two studies from South Africa have also examined discrimination in relation to adolescent risk behaviors (Brook et al. 2006b; Kalichman et al. 2006). Studies in Norway (Oppedal et al. 2005), Denmark (Montgomery and Foldspang 2007), the Netherlands (Veling et al. 2007; Stevens et al. 2005a), Spain (Pantzer et al. 2006), Bosnia, Croatia and Austria (Sujoldzic et al. 2006), Hong Kong (Lam et al. 2005) and Canada (Beiser and Hou 2006; Noh et al. 2007; Etowa et al. 2007) have examined the association between perceived discrimination and health for multiple immigrant groups.

It is also noteworthy that very few studies explicitly examine the role of discrimination in accounting for racial disparities in health. Some early studies provided evidence that discrimination makes an incremental contribution to SES in explaining disparities (Williams et al. 2003). A few recent studies find that perceived discrimination accounts for some of the racial disparities in health. This is evident for Maori-European disparities on four indicators of self-reported health in a national study of New Zealand (Harris et al. 2006a), Aboriginal–non Aboriginal variations in self-reported physical and mental health in Australia (Larson et al. 2007), and in U.S. studies for black-white differences in health care trust (Adegbembo et al. 2006), sleep quality and physical fatigue (Thomas et al. 2006) and Hispanic-white differences in PTSD symptoms (Pole et al. 2005).

Discriminatory experiences that are acute and observable and are analogous to life events in the stress literature are captured by many of the other commonly used measures of discrimination in recent studies. These include the Experiences of Discrimination scale (Krieger 1990), the Schedule of Racist Events (Landrine and Klonoff 1996), the Major Experiences of Discrimination scale (Williams et al. 1997; Kessler et al. 1999); the Racism and Life Experiences Scale (Harrell 1997), and the Index of Race-Related Stress (Utsey and Ponterotto 1996). Prior research has shown that failure to assess stress comprehensively leads to an underestimation of the effects of stress on health (Turner et al. 1995). The current assessment of discrimination tends to neglect the measurement of chronic stressors in major domains of life such as work. Chronic stressors refers to experiences that provide persistent negative exposure to threat or excessive demand (Baum et al. 1993). The stress literature indicates that although chronic stressors are difficult to measure, they are stronger predictors of the onset and course of the disease than acute life events (Cohen et al. 1995). It is noteworthy that capturing chronic exposure to discrimination over time, as assessed by the Everyday Discrimination Scale, was associated with subclinical cardiovascular disease (Lewis et al. 2006). The Perceived Racism Scale (McNeilly et al. 1996) captures some aspects of chronic discrimination but more effort is needed to comprehensively characterize chronic and ongoing experiences of discrimination, especially its multiple dimensions in the domain of work, a major site of discriminatory experiences in contemporary society.

Traumas are a class of stressful experiences that can have long-lasting negative effects on health (Stam 2007; Pearlin et al. 2005), that have been neglected in the discrimination literature. Traumas are distinct from life events in that they capture events that are extreme, overwhelming and horrific in impact. It is likely that traumatic experiences are reported on some of the life events-like measures of discrimination but inadequate detail is ascertained to distinguish them from less severe experiences. Carter (2007) has emphasized the importance of assessing race-based traumatic experiences as distinct from major experiences of discrimination. He argues that because there is likely to be intense emotional reaction to these severe, life threatening or dangerous experiences, they have great potential for psychological injury.

The stress literature has also recognized macro-stressors as one component of stressor exposure. These are large-scale system-related stressors such as economic recessions or natural disasters. They provide indirect exposure to stressors, that can have “collateral effects” on individuals (Yehuda et al. 2005). Research reveals that events such as earthquakes, terrorist attacks and the onset of war can trigger increases in acute symptoms of heart disease, increased hospital admissions and heart disease mortality (Bhattacharyya and Steptoe 2007). Highly publicized race-related traumatic events, such as extreme examples of police brutality could have similar effects. Some of the items on the Index of Race-Related Stress (such as references to racial abuses of the Jim Crow era) capture aspects of macro-stressors (Utsey and Ponterotto 1996) but comprehensively assessing the potential contribution of large-scale, race-related traumatic events will require researchers to capitalize on emergent opportunities to assess the health consequences of macro-stressors. Such efforts could utilize some of the strategies used in the larger stress literature such as creatively using hospital admissions and vital statistics data. Future research needs to identify the extent to which major race-related stressors can initiate new disease processes or exacerbate existing disease. There is no agreement in the stress literature on the length of time from the emotional trigger from a macro-stressor to the onset of symptoms. However, some research suggests that cardiac mortality tends to be elevated for at least 6 months post-bereavement (Bhattacharyya and Steptoe 2007).

Researchers should also be alert to the possibility that macro-stressors that are ostensibly unrelated to race or ethnicity, can be racialized in ways that can generate increased discrimination for socially stigmatized groups. The terrorist attacks on 11 September 2001 are an example. These incidents had documented negative health consequences (DiMaggio et al. 2007), but they also triggered increased discrimination and harassment targeted to Arab Americans in the 6 months after the terrorist attacks (Lauderdale 2006). Lauderdale (2006) found that Arab American women in California had an increase in the rate of low birth weight and pre-term birth in the 6 months after September 11 compared to the 6 months before. Other women in California did not experience a change in birth outcome risk post September 11.

Research reveals that severe events are recalled better than less severe events (Monroe 2008), so to the extent that the focus is on the assessment of severe discriminatory incidents the recall problem may be somewhat minimized. More importantly, the assessment tools for the assessment of discrimination need to be appropriate to the task. More research is needed on how experiences of racial discrimination are stored in memory and best accessed for recall. In the meantime, research studying lifetime exposure to discrimination should consider using an event history calendar. It is a procedure that has been developed by cognitive psychologists that capitalizes on current scientific understanding of the nature of autobiographical memory to assess experiences over the life course (Belli 1998). More generally, research by cognitive psychologists and survey methodologists provide many insights into how respondents understand, interpret, and respond to questions that would enhance the collection of data on discrimination (Schwarz 2007). We consider a few examples.

The sensitive nature of the topic of race and racial discrimination has implications for how the discrimination variable should be assessed and the accuracy of reports of discrimination (Williams et al. 2003). Recent research on race-of-interviewer effects indicates that blacks are reluctant to reveal their true racial beliefs on race sensitive questions when talking to white interviewers. Instructively, Krysan and Couper (2003) found that the strongest effect of blacks being deferent to a white interviewer was for perceptions of racial discrimination (compared to attitudes on four other categories of race-related questions regarding racial and race-associated policies, black politics and the pace of civil rights). This pattern held both for in-person interviews and for self-administered interviews with a digital video of the interviewer. Irrespective of the race of the interviewer, making race salient in the assessment of discrimination can lead to response bias compared to the use of neutral terminology (Gomez and Trierweiler 2001). Many questions used to assess discrimination explicitly ask respondents to report on “racial discrimination” or experiences of discrimination “because of your race.” In contrast, the approach of Williams and his colleagues (Williams et al. 1997; Kessler et al. 1999) frames the questions about discrimination in terms of unfair treatment and asks about attribution only after a behaviorally descriptive experience, without emotionally charged language, has been endorsed. This approach seeks to address not only the problem of the sensitivity of questions regarding discrimination but also concerns about the problem of attributional ambiguity. Respondents are often uncertain of the reason (or attribution) for a specific interpersonal incident. Thus, building attribution into the question is likely to underestimate discriminatory encounters for which the attribution is uncertain (Williams et al. 2003). Asking questions about both racial and non-racial discrimination may capture more of the potential pathogenic phenomenon of perceived unfairness, and also reduce some of the measurement error that can occur if questions are asked only of racial discrimination. However, there is debate regarding optimal measurement approaches for perceived racial discrimination (Kressin et al. 2008), and limited empirical evidence on the effects, if any, that building discrimination and racial terminology into the assessment of perceived discrimination has on respondents’ willingness and ability to recall and report these experiences.

An unresolved issue in the literature is the extent to which unfair treatment based on race may have effects that are distinctive from other forms of unfair treatment. Because of the centrality of race in American society, the salience of racial identity can affect the appraisal processes of some individuals in ways that could lead race-attributed experiences to be more impactful because they are especially threatening to an individual’s sense of rights and opportunities (Pearlin et al. 2005). Some studies have found that perceptions of racial and non-racial discrimination are similarly related to health (Williams et al. 1999; Kessler et al. 1999). Recent neuroimaging research indicates that the experience of unfairness is associated with negative emotional responses and can activate regions of the brain involved with emotional regulation, suggesting that seeking justice and fairness may be a basic human impulse and its violation can trigger physiological consequences (Tabibnia et al. 2008). Accordingly, irrespective of attribution, the perception of unfair treatment may generate distress. For example, in the Whitehall study, perceived unfairness has been related to incident coronary events (De Vogli et al. 2007a), incident psychiatric morbidity (Ferrie et al. 2006), and metabolic syndrome (De Vogli et al. 2007b). These studies were not framed within the context of discrimination but unfairness is operationalized with measures similar to those used in the discrimination literature.

Lewis et al. (2006) recently reported that although Everyday Discrimination attributed to race was unrelated to coronary calcification for black women, a combined measure capturing racial and non-racial discrimination was positively associated with coronary calcification. On the other hand, one study found that black women who attributed chronic discrimination to race demonstrated greater blood pressure reactivity than those who attributed them to other social status categories (Guyll et al. 2001). Future research needs to more systematically assess the extent to which racial discrimination differs in its causes and consequences from other types of discrimination and the extent to which the approach to capturing attribution affects our understanding of the levels and health consequences of racial discrimination. Some limited evidence suggests that racial discrimination as a stressor may differ from other stressors, possibly because its threat may be more systematic, insidious and constant than other stressors (Stetler et al. 2006).

More generally, research on asking sensitive questions in survey research reveals that to the extent that respondents perceive questions regarding discrimination to be socially unacceptable or undesirable, they are likely to underreport those experiences (Tourangeau and Yan 2007). Research reveals that the mode of administration of sensitive questions makes a difference in terms of the response. In particular, the presence of others in the interview context adversely affects accurately collecting complete data. Thus, eliminating the presence of an interviewer by using a self-administered instrument and using “forgiving” or normalizing wording for sensitive questions can be helpful in addressing this issue (Tourangeau and Yan 2007).

Measuring discrimination accurately will also require researchers to not only capture the multiple domains of discrimination but to ensure that adequate questions are asked in each domain. In the assessment of multiple phenomena, survey methodologists find that multiple questions about components of a phenomenon will provide a more accurate level than a few global questions (Schaeffer and Presser 2003). Multiple questions are more likely to clearly convey what is being asked and to yield a more thorough search of memory. For example, researchers have found that population-based reports of alcohol consumption markedly under-report alcohol use compared to data on taxable alcohol available for consumption. However, assessing alcohol use with detailed, within-location, beverage-specific questions (asking respondents whether they had consumed specific alcoholic beverages, at any of several specific locations and then about how much and how often they drank in each location) accounted for 94% of the taxable alcohol available for consumption compared to the 40–60% with standard alcohol use questions (Casswell et al. 2002). For each class of discriminatory experiences, similar attention should be given to ensuring that all relevant contexts and components are assessed.

A challenge to getting a valid measure of discrimination via self-report is that some individuals cope with stress by denying its occurrence. Studies reveal that among patients with cancer, four to 47% deny the diagnosis, 8–70% deny the impact and 18–42% deny affect (Vos and de Haes 2007). Related constructs include avoidance, distancing, suppression and repressive coping. Denial can reflect conscious or unconscious efforts to minimize the pain of negative experiences. It has been argued that the emotional pain of racism can render some individuals unable to recall specific events (Carter 2007). Vos and de Haes (2007) suggest that denial should be viewed not as a one-time event, but as a process in which there is a continuum from facts to ambiguous events. Accordingly, denial can be a passive escape strategy linked to poorer psychological function, or it can be part of a series of active distractive strategies that are adaptive and lead to lower levels of psychological distress. Getting a clearer sense of the levels and consequences of denial in research on discrimination should be a priority for future research.

The challenge then is to identify and assess those dimensions of discriminatory experiences that are likely to have long-term negative effects. The stress literature suggests that several characteristics of stressors are important determinants of the long-term negative impact of stress. Stressors that are ambiguous, negative, unpredictable, and uncontrollable are particularly pathogenic (Carter 2007; Dougall et al. 1999). The intensity of the stressor also matters including how disturbing and upsetting it is (Dougall et al. 1999). The frequency and duration of stressors are also key determinants of their impact with chronic or repeated stressors or prolonged exposure being predictive of adverse effects. Such stressors or difficulties are likely to make continuing demands or pose ongoing threats (Dohrenwend 2006). The impact that the stressor has on the environment and social functioning of the individual is also important. Stressors that occur in central role areas of an individual’s life, affect multiple areas, lead to loss of resources, have objective negative impact on the normal activities of the individual, and cause a lot of change, disruption or readjustment are likely to be very consequential (Dohrenwend 2006; Carter 2007). The presence of symptoms such as post traumatic or peritraumatic disassociation and of panic reactions appear to predict long term negative effects of exposure to traumas (Yehuda et al. 2005).

An important priority in the future assessment of perceived discrimination is to assess markers of the stressfulness of experiences. A central problem in the assessment of stress is what Dohrenwend (2006) calls “intracategory variability.” That is, the categories on life events scales are typically so broad (death of a loved, unemployment, or serious illness or injury) that they capture experiences that can vary in their stressfulness and impact. Knowing that such an event occurs provides no information on how negative, unexpected, and undesirable, the event was. The same is true for measures of discrimination in employment, housing or in interaction with the police. Researchers studying discrimination should devote more attention to assessing the severity of discriminatory incidents by capturing the number, intensity, and duration of these experiences (Carter 2007).

The stress literature offers three options for assessing severity. First, the narrative-rating methodology is a labor intensive interview that gathers details about each potentially stressful experience so that trained researchers can then rate them on multiple dimensions of stressfulness (Dohrenwend 2006). This approach has been shown to be superior to standard checklists of stressful events but because interviewing and rating can take as much as 16 hours per individual interview (Dohrenwend 2006), it is too time consuming and expensive to be a practical option for most researchers. A second approach is to clearly define what kinds of experiences should be included in a category and/or spell out the inclusion or exclusion criteria for the target stressful experience (Dohrenwend 2006). For example, in the Traumatic Life Events Questionnaire (Kubany et al. 2000), instead of asking the respondent if s/he had been in a motor vehicle accident, the respondent is asked “were you involved in a motor vehicle accident for which you received medical attention or that badly injured or killed someone.” Similarly, the question assessing the presence of childhood physical abuse is “were you physically punished in a way that resulted in bruises, burns, cuts or broken bones?” (Kubany et al. 2000). This strategy could be applied to questions about racial discrimination in which behaviorally descriptive language that avoided global and emotionally charged words could clearly specify the experiences that should be included. This approach can improve assessment but has the downside of potentially missing other important stressors that do not fall within the specified criteria (Dohrenwend 2006).

A third strategy involves subjective ratings by the respondent of the severity and negative impact of the stressful experience (Cohen et al. 2007). In the PTSD literature, respondents are often asked after reporting a particular event to indicate how much they had been affected by it and how upset they had been by it (Carter 2007). Similarly, a study relating caregiver stress to mortality had respondents indicate “how much of a mental or emotional strain” each reported caregiving task had been (Schulz and Beach 1999). A recent measure of hurricane-related stressors required respondents to provide a global rating of the 29 stressors ascertained by indicating “how stressful overall” the experiences had been on a 0–10 scale, “where 0 means not at all stressful and 10 means the most stressful thing you can imagine” (Kessler et al. 2008). The researchers then compared respondents rating their stress as severe (9–10), serious (7–8), moderate (5–6) or mild (3–4) to those who did not rate it as stressful (0–2). Such approaches lead to stronger associations between life events and mental health in the general stress literature (Dohrenwend 2006), but this approach has been used in only a few studies in research on discrimination and health.

Analysis of data from the Metro Atlanta Heart Disease Study illustrates the promise of this approach. This study found that although perceived discrimination was unrelated to hypertension, both discrimination at work (Din-Dzietharn et al. 2004) and discrimination more generally (Davis et al. 2005) were associated with increased risk of hypertension, but only among persons reporting high levels of stress because of discrimination. In this study, if respondents reported experiences of discrimination they were asked to rank their general level of stress when they had those experiences from 1 = none to 5 = high. Several states participating in the annual Behavioral Risk Factor Surveys in the U.S. have included the Reactions to Race module, developed by Camara Jones, which includes questions that assess emotional and physical symptoms as a result of exposure to discriminatory experiences. This is a fertile opportunity to explore the contribution of ratings of severity to the association between discrimination and health. One limitation of obtaining appraisals of stressfulness is that for studies of mental health, respondents’ reports of stressfulness can lead to confounding between the measure of stress and the self-reported outcome (Dohrenwend 2006).

Pearlin et al. (2005) emphasized that the stressors that are patterned by social disadvantage are the “serious stressors” that capture major hardships, conflicts, and disruptions in life. These include disorderly transitional events which are role changes that are non-normative, undesired, involuntary and sometimes irreversible, such as teenage parenthood or school dropout. These stressors are concentrated among low SES groups and in addition to their negative emotional impact, they are critical in transmitting social disadvantage from one generation to the next because they tend to place low SES persons on trajectories of low education, low job prospects, and low income that lead to the proliferation of other stressors. Financial stressors, especially those that are characterized by continuity and repetitiveness over the life course are among the most powerful of stressful life experiences (Pearlin et al. 2005). Other sources of social and economic adversity, especially those that are chronic and recurring and that occur in major social domains such as the role of breadwinning, work, and family should also be assessed.

Discrimination should be assessed within this larger social context of the multiple stressful exposures within which it is embedded. Research is needed to elucidate, in careful longitudinal analyses, how perceived discrimination relates to other types of stressors and combines with them to produce patterns of cumulative exposure to multiple adversities that can adversely affect health status. The processes may be complex. Experiences of discrimination such as the loss of one’s job can easily lead to “stress proliferation processes” in which the primary stressor of unemployment can give rise to multiple other types of secondary stressors, such as financial strain and family conflict (Pearlin et al. 2005). Traumas are among the most potent types of stressful experiences that can trigger stress proliferation with the secondary stressors that are triggered by traumas contributing more to later health than the primary trauma itself (Pearlin et al. 2005).

Understanding how discrimination relates to other stressors will require examining the ways in which multiple forms of psychosocial stress accumulate to adversely affect health. The stress literature suggests that one’s ability to manage a new stressor is reduced by the burden and demands of preexisting stressors (Cohen et al. 2007). Moreover, stressors may combine not only in additive ways but also in interactive ways. Future research on perceived discrimination should pay special attention to potential interactions among stressors. This includes attention to environmental stressors linked to the physical, chemical, and built environment. Some limited evidence indicates that psychosocial stressors and environmental factors may interact with each other. One study found that high levels of air pollution were associated with distress among people with recent life events, but unrelated to distress among persons with no social stressors (Evans et al. 1987). Another study of an Indian sample, and two U.S. college student samples, found that social stressors adversely affected mental health only among persons living under the environmental condition of crowding (Lepore et al. 1991).

Too often there is little consideration to identifying or thinking about the exposure and lag times that would be necessary for a relationship to exist between exposure to discrimination and subsequent illness. Most chronic illnesses such as cancer, CHD, diabetes, and hypertension develop over many years and are often diagnosed long after the disease process was initiated. Accordingly, recent exposure to stressors, including discrimination, should not be related to the onset of these conditions. At the same time, because stress can impact the course of disease, it is important to consider how stress might affect the trajectory of an illness. This is especially important given the large racial and SES disparities in the progression of disease. As noted earlier, some recent studies have begun to pay attention to the role of discrimination in the management of chronic illness, healthcare seeking behaviors and in adherence to medical treatment. This is a very promising area in the study of discrimination and chronic disease and is consistent with the literature on stress that indicates that one of the important ways in which stress affects health is by shaping behavioral management of disease and leading to particular health behaviors that can have negative health consequences (Cohen et al. 2007). In future research, increased attention should be given to outcomes that capture the management, course, progression, severity, and recurrence of illness.

The stress literature also suggests that the types of stressors and the aspects of stress that may be important in determining the risk of getting an illness may be different from those aspects that are determinants of the progression, course, and severity of the illness. That is, the factors that are linked to the onset of disease may be different from those that overwhelm the body’s defenses in coping with illness. The distinction between chronic and acute discrimination may be important for the underlying pathways by which discrimination-induced stress can lead to disease. As with the general literature on stress, acute experiences of discrimination may trigger acute episodes of illness while chronic discrimination may exacerbate existing disease processes (Bhattacharyya and Steptoe 2007). In the absence of coronary disease, for example, severe emotional distress from acute stress can trigger acute cardiovascular responses and events that can lead to cardiovascular dysfunction. On the other hand, chronic stressors can accelerate the atherosclerotic processes and lead to more rapid progression of disease (Brotman et al. 2007). Similarly, mental health research reveals that major stressful life events (that require a lot of change in usual activities) lead to the onset of psychopathology, while minor stressful experiences play a role in the recurrence and severity of psychopathology (Dohrenwend 2006). Future research on discrimination and health needs to pay greater attention to matching the measure of discriminatory experience with the presumed disease process.

Research is also needed to elucidate the linkages between experiences of discrimination and processes of illness. Ackerman et al. (2002) examined the role of life events in exacerbating episodes of multiple sclerosis (MS). They followed 23 women with MS for a year and conducted a weekly assessment of stress. They found that life events served to rapidly precipitate the relapse and the progression of disease, occurring an average of 14 days before the exacerbation of MS. The study also found that a broad range of stressors were equally associated with the processes of exacerbating the disease. This type of intensive study can serve as a useful model for future research that can shed light on the pathways from discrimination to health.

Gender is another social variable that might affect the relationship between discrimination and health. Consistent with the view that black men are more likely to be targets of discrimination than black women because of gendered stereotypes that view them as more threatening, men tend to report higher levels of discrimination than women (Carter 2007). Gender differences in the level and consequences of a stressor can be evident in opposite directions. For example, men report higher levels of exposure to traumas but PTSD is more prevalent in women (Stam 2007). One recent study found that gender moderated the association between discrimination and anxiety but not depression (Banks and Dracup 2006) while another found that the association between discrimination and physical and mental health was stronger for women than for men (Borrell et al. 2006). It is also important to explore the intersections of race, class and gender. One study found that race-related stress had larger negative effects on middle class than working class men, suggesting that the additional resources of the middle class did not protect them from the negative effects of stressors (Pieterse and Carter 2007).

The shade of skin color (or skin tone) is another marker of social status and a potential predictor of exposure to discrimination that has received inadequate research scrutiny (Krieger 1999). Research has long indicated that skin tone is a marker of social status and an important predictor of access to socioeconomic opportunities and resources within the black population with the associations being stronger for women than for men (Keith and Herring 1991). Prior research has shown that skin tone is also a marker for discrimination, with darker skinned blacks reporting higher levels of discrimination than their lighter skinned peers (Keith and Herring 1991; Carter 2007). Similar patterns have been observed among Hispanics (Arce et al. 1987), and Jews (Kraus and Koresh 1992). It is not clear though, if this association exists in all contexts. For example, in the CARDIA study of African American young adults, skin color was unrelated to reports of discrimination (Borrell et al. 2007). Insufficient research attention has been given to the relationship of skin color to discrimination in recent research that would allow conclusions regarding either secular change in the association over time, or the identification of the conditions under which particular patterns are more or less likely to be evident. Some evidence indicates that skin tone continues to matter for the earnings of African Americans (Goldsmith et al. 2007), but it is unclear if there have been secular changes in its role as a marker for discrimination. Future research needs to examine the extent to which multiple social statuses combine to affect both the levels of exposure to discrimination and the effects that discrimination can have on health.

The research reviewed also raises larger questions for future research and policy regarding health and its determinants. The accumulating evidence emphasizes that health policy, across multiple societies needs to encompass the legacies of racial and ethnic inequality and the levels of intolerance, incivility and anti-immigrant sentiment. These factors appear to matter a lot for the health of targeted groups and as such require greater attention as a focus of health policy. Racism and ethnocentrism may not be inevitable. In the U.S., there have been marked declines in racial prejudice and discrimination in the last several decades that have resulted from a broad range of interventions (Schuman et al. 1997). However, there is still considerable opportunity to improve relations among population groups defined by race, ethnicity, migration history and other stigmatized social statuses. There is also the need to more seriously begin to provide targeted relief to individuals suffering from exposure to discrimination. One recent study provided the sobering finding that a written disclosure intervention that has been shown to be successful in improving health outcomes such as immune functioning among persons exposed to various stressors was not effective when applied to persons dealing with racial discrimination (Stetler et al. 2006). This raises the possibility that conventional stress management strategies may not be effective in relieving the personal suffering linked to racial discrimination.