Sociodemographic groups at risk: race/ethnicity.

Typically, when the term “health disparity” is used, disparities in health related to or associated with race and/or ethnicity are what is meant. Disparities related to race and ethnicity are indeed the topic of this discussion, but there are many other types of health disparities that are often tightly linked to race/ethnic disparities, such as those related to sex, socioeconomic status, and region (such as the Stroke Belt), that should not be overlooked. Why do health disparities in race/ethnic minority groups occur? There are many potential explanations, including genetic factors and common environmental exposures. There are also likely many potential important cultural differences in perceptions of health and the healthcare system that shape the behavior of inhabitants of their culture, including but not limited to social support structure, mistrust/varying expectations of the medical system, dietary differences, physical activity norms, medical compliance, fear and/or denial, and fatalism. There are many “access to care” issues for race/ethnic minorities that could potentially interfere with health, such as poverty, health literacy and numeracy, language barriers, access to transportation, and child care. Finally, the intrinsic structure of the healthcare system lends itself to health disparities. Previously, it has been shown that the majority of care for race/ethnic minorities is provided by very few providers, who are then overwhelmed and unable to provide the highest quality of care.1 Also, medical professional stereotyping or discrimination and cultural biases are likely prevalent in some areas. Overall, the Institute of Medicine report regarding racial disparity in 2003 showed that even when access to care issues were controlled for, the overall quality of care was poorer for race/ethnic minorities.2 A thorough review of all racial disparities in stroke is not possible within the focus of this short review. Therefore, this review will focus mostly on racial disparities regarding stroke in US blacks, the racial group found to be at the highest risk for stroke death compared with all other race/ethnic minorities within the United States (Figure 1).3 National statistics from death certificate data have long shown an increase in stroke mortality for blacks,4 but until recently, it was unclear whether this was related to higher stroke incidence or a higher fatality rate after stroke. It has now been shown that this higher stroke mortality exists because blacks have a higher stroke incidence compared with whites, although the case-fatality rate is similar between the 2 races.5 Within the Greater Cincinnati/ Northern Kentucky population of 1.3 million, a large epidemiology study of stroke has been ongoing since 1988 that captures all hospitalized cases of stroke, along with a sampling of out-of-hospital events every 5 years. This allows the calculation of standardized stroke incidence rates for blacks and whites. Overall, blacks had nearly double the incidence of stroke (including ischemic and hemorrhagic subtypes) when compared with whites (Table 1). Interestingly, there was a striking association with age, in that blacks younger than 55 years seem to be at particularly high risk (2 to 5 times higher risk than similarly aged whites), but by the time elderly ages are achieved, the racial disparity is significantly attenuated. Unfortunately, this racial disparity in stroke incidence does not appear to be changing over time, as there was still a significant disparity in 1999 as there was in 1994.6 Socioeconomic disparity was mentioned earlier as a possible contributor to race/ethnic disparities; therefore, this was explored within the same Greater Cincinnati population as a possible explanation for the increased stroke incidence among blacks. With the use of aggregate measures of socioeconomic status (percentage of citizens within a US census tract living below the poverty level), incidence rates for whites and blacks were calculated as stratified by poverty status of the community of residence, and the contribution of socioeconomic status to the excess