The health status of racial and ethnic minority groups in the U.S. has improved steadily over the last century. Despite such progress, disturbing disparities in health persist between majority and minority populations. For example, the average life expectancy for a white infant born in 1999 is 77.3 years, but is only 71.4 years for an African American infant.6 Demographic projections predict a substantial change in the racial and ethnic makeup of the older population, heightening the need to examine and reduce differences in health and life expectancy. Research to date has shown that health disparities are associated with a broad, complex, and interrelated array of factors. Disease risk, diagnosis, progression, response to treatment, caregiving, access to care, and overall quality of life each may be affected by variables such as race, ethnicity, gender, socioeconomic status, age, education, occupation, country of origin, and possibly other lifetime and lifestyle differences.
The NIA is committed to addressing health disparities through its research programs. For example, Satellite Diagnostic and Treatment Centers, part of the national Alzheimer's Disease Centers (ADC) Program, have successfully recruited African Americans, Hispanics, Native Americans, and American Indian/Alaska Natives to AD prevention and treatment studies. Researchers on the NIA's Religious Orders Study have made a major effort to enroll African American members of the Catholic clergy; the nature of the study population enables the etiology and pathology of AD to be established among individuals with similar educations, occupations, socioeconomic status, and lifestyles. Five ADCs received funding in 2000 and 2001 specifically to encourage minority-related research, and in 2001 half of the NIA Director's Reserve funds, which encourage collaborative research projects, were allocated to minority-focused research. In addition, the NIA recently completed a year-long review of these issues and developed a comprehensive strategic plan to address health disparities in the older population.
Water, Race, and Health. During the early 1900s, the United States began to notice a dramatic decrease in mortality rates from infectious diseases. The tremendous decline in infectious disease prevalence was due primarily to increased sanitation and hygienic practices that were implemented at the community level. For instance, the advent of waste disposal services had a profound impact on declines among certain population groups, as did water purification measures. However, most sanitation services were reserved for affluent communities, which consequently resulted in health disparities between social classes. Given the demographic profile in the United States, these disparities were particularly apparent between different immigrant and racial groups.
An NIH-supported researcher investigated the claim that public water companies provided black communities with better service than private water companies. The research drew from three independent sources of econometric evidence: 1) an analysis of typhoid fever rates in cross-sections of American cities in 1911 and 1921; 2) an analysis of waterborne disease rates in a panel of fourteen North Carolina towns between 1889 and 1908; and 3) an analysis of investment patterns in cities with public and private water companies. A case study of New Orleans, which municipalized its water system in 1908, complements the statistical evidence. All of these sources indicate public ownership reduced white disease rates only slightly, but reduced black disease rates sharply. This research both underscores the importance of public health in reducing mortality and shows how public health innovations can be used as a mechanism to reduce health disparities.
Medical Care and Racial Disparities in Survival After a Heart Attack. In a study of Medicare beneficiaries ages 66 to 74 who were admitted to a U.S. hospital due to a heart attack, NIH-supported researchers found that the black patients did not live as long after discharge from the hospital as white patients. Much of this disparity could be explained by the lower rate among black patients in the use of cardiac procedures such as revascularization (one of several surgical procedures to reestablish blood flow to part of the heart) and implantable cardioverter defibrillators (devices that regulate heartbeat). This result suggests that expanded use of effective procedures in black patients would substantially reduce racial differences in long-term survival, and that racial disparities in lifespan following a heart attack could be reduced if systematic medical procedures were employed.
Selected Future Research Directions in Health Disparities
Healthy Aging in Neighborhoods of Diversity across the Lifespan (HANDLS). The need to understand the driving factors behind persistent black-white health disparities in overall longevity, cardiovascular disease, and cerebrovascular disease has led to the development of the HANDLS study, a community-based research effort designed to focus on evaluating health disparities in socioeconomically diverse African-Americans and Whites in Baltimore. This study is unique because it is a multidisciplinary project that will assess physical parameters as well as evaluating genetic, demographic, psychosocial, and psychophysiological parameters over a 20-year period. It will also employ novel research tools, mobile medical research vehicles to improve participation rates and retention among non-traditional research participants. HANDLS will investigate the longitudinal effects of socioeconomic status and race on the development of cerebrovascular disease and cardiovascular disease; changes in psychophysiology, cognitive performance, strength and physical functioning, health services utilization, and nutrition, and their influences on one another and on the development of cardiovascular, cerebrovascular, and cognitive decline. Selecting a cohort that spans ages 30-64 at baseline enhances the opportunities to gain insights into minority aging and the development of age-related disease over the planned 20 years of this study.
- National Center for Health Statistics. National Vital Statistics Report 50 (March 21, 2002), pp. 33-34.