Alzheimer’s disease: The African American story

Introduction. African Americans have historically been underrepresented in research studies into Alzheimer's disease (AD) and other dementias in the United States. However, over the past decade there have been an increasing number of clinical and epidemiological studies in dementia that have included significant numbers of African Americans and have increased our knowledge of the nature and extent of the disease in this population. Incidence of dementia and AD in African Americans. There are now several large cohort, population-based studies reporting on the incidence of dementia and AD in elderly African Americans. Two of these studies, which involve multiracial comparisons, the Chicago Study on Health and Aging and the Northern Manhattan Study, have reported higher incidence rates for African Americans as compared to whites. The age specific incidence rates for AD in African Americans in these two studies are similar (Chicago 65–74 1.79%, 75–84 6.06%, 85+ 12.72%, North Manhattan 65–74 1.7%, 75–84 4.4%, 85+ 11.4%). These rates are also similar but somewhat higher than the incidence rates reported from African Americans from the Indianapolis–Ibadan dementia project. (65–74 1.38%, 75–84 3.29%, 85+ 7.07). When the Indianapolis incidence rates for AD and dementia are compared to a meta-analysis, which included published incidence rates from other populations, the rates for African Americans are at the higher end of reported rates from other studies. Not all studies agree, however.