The risk for developing Alzheimer's disease among older African Americans may be two to three times greater than in the non-Hispanic white population and they also differ in terms of risk factors and manifestation of the disease, as found in reviews of researches in a new study by researchers at the Rush University Medical Center. The study results will be published in the April 7 issue of Health Affairs.
"The older African American population is growing at a rapid pace, and the burden of aging-related cognitive impairment and Alzheimer's disease will continue to present a tremendous challenge," said Lisa Barnes, PhD. "This study highlights the importance of research among minority groups within the communities in which hospitals serve."
Barnes is the primary author and director of the Rush Center of Excellence on Disparities in HIV and Aging in the Rush Alzheimer's Disease Center, and professor of Neurological Sciences and Behavioral Sciences at Rush University Medical Center.
"The lack of high-quality biologic data on large numbers of racial and ethnic minorities poses barriers to progress in understanding whether the mechanisms and processes of Alzheimer's disease operate the same or differently in racial and ethnic minorities and, if so, how, particularly in the high-risk African American population," said Barnes.
In 2010, the U.S. Census Bureau indicated that 20 percent of the population ages 65 and older was a racial or ethnic minority member. Current projections suggest that by 2050, 42 percent of the nation's older adults will be members of minority groups. Among those ages 85 and older, 33 percent are projected to be a minority.
"Delaying disease onset is the most critical component to reducing racial disparities in Alzheimer's disease," said Barnes. "In order to prevent the disease, we must first identify risk factors for cognitive decline and development of Alzheimer's. This would help us to create strategies to modify behavior and develop effective treatment plans."
Research suggests that there may be a combination of biologic, cultural, health systems-based and other factors that may be contributing to the risk of developing Alzheimer's disease in African Americans when compared to non-Hispanic whites. They maintain that cognitive tests done over time actually indicate small or no differences in performance among these populations and that studies on risk factors have produced useful, yet insufficient, explanations of the disparities-largely due to the lack of African American participation in research studies.
"In order to understand why Alzheimer's is more prevalent among African Americans and why it manifests itself differently, we would need more African Americans research participants in Alzheimer's disease studies and we would need to look at a range of risk factors and their effects on cognition over time," said Barnes. "This would require us to go beyond traditional cognitive function tests, and instead, include imaging, biomarkers, and autopsy studies, to aid in accurate diagnosis."
The study was supported by the National Institute on Aging and the Illinois Department of Public Health.
Rush (www.rush.edu) is a not-for-profit academic medical center comprising Rush University Medical Center, Rush University, Rush Oak Park Hospital and Rush Health.
The Rush Alzheimer's Disease Core Center is one of 29 Alzheimer's disease research centers across the country designated and funded by the National Institute on Aging. Investigators are focused on four main areas of research, including risk factors, neurological basis of the disease and improving diagnosis and treatment.